CLCA1 is Poorly Expressed in Stomach Adenocarcinoma and Correlates with Immune Infiltration / CLCA1 se Expresa Deficientemente en el Adenocarcinoma de Estómago y se Correlaciona con la Infiltración Inmune

SUMMARY: Calcium-activated chloride channel regulator 1 (CLCA1) is associated with cancer progression. The expression and immunologic function of CLCA1 in stomach adenocarcinoma (STAD) remain unclear. In this investigation, the expression of CLCA1 in STAD tissues and its involvement in the progression and immune response of STAD were examined using databases such as cBioPortal, TISIDB, and UALCAN. In order to validate the expression level of CLCA1 protein in gastric adenocarcinoma, thirty clinical tissue specimens were gathered for immunohistochemical staining. The findings indicated a downregulation of CLCA1 in STAD patients, which was correlated with race, age, cancer grade, Helicobacter pylori infection, and molecular subtype. Through the examination of survival analysis, it was identified that diminished levels of CLCA1 within gastric cancer cases were linked to decreased periods of post-progression survival (PPS), overall survival (OS), and first progression (FP) (P<0.05). The CLCA1 mutation rate was lower in STAD, but the survival rate was higher in the variant group. The correlation between the expression level of CLCA1 and the levels of immune infiltrating cells in STAD, as well as the immune activating molecules, immunosuppressive molecules, MHC molecules, chemokines, and their receptor molecules, was observed. Gene enrichment analysis revealed that CLCA1 may be involved in STAD progression through systemic lupus erythematosus (SLE), proteasome, cell cycle, pancreatic secretion, and PPAR signaling pathways. In summary, CLCA1 is anticipated to function as a prognostic marker for patients with STAD and is linked to the immunization of STAD.

El regulador 1 del canal de cloruro activado por calcio (CLCA1) está asociado con la progresión del cáncer. La expresión y la función inmunológica de CLCA1 en el adenocarcinoma de estómago (STAD) aún no están claras. En esta investigación, se examinó la expresión de CLCA1 en tejidos STAD y su participación en la progresión y respuesta inmune de STAD utilizando bases de datos como cBioPortal, TISIDB y UALCAN. Para validar el nivel de expresión de la proteína CLCA1 en el adenocarcinoma gástrico, se recolectaron treinta muestras de tejido clínico para tinción inmunohistoquímica. Los hallazgos indicaron una regulación negativa de CLCA1 en pacientes con STAD, que se correlacionó con la raza, la edad, el grado del cáncer, la infección por Helicobacter pylori y el subtipo molecular. Mediante el examen del análisis de supervivencia, se identificó que los niveles reducidos de CLCA1 en los casos de cáncer gástrico estaban relacionados con períodos reducidos de supervivencia posterior a la progresión (PPS), supervivencia general (OS) y primera progresión (FP) (P <0,05). La tasa de mutación CLCA1 fue menor en STAD, pero la tasa de supervivencia fue mayor en el grupo variante. Se observó la correlación entre el nivel de expresión de CLCA1 y los niveles de células inmunes infiltrantes en STAD, así como las moléculas activadoras inmunes, moléculas inmunosupresoras, moléculas MHC, quimiocinas y sus moléculas receptoras. El análisis de enriquecimiento genético reveló que CLCA1 puede estar involucrado en la progresión de STAD a través del lupus eritematoso sistémico (LES), el proteasoma, el ciclo celular, la secreción pancreática y las vías de señalización de PPAR. En resumen, se prevé que CLCA1 funcione como un marcador de pronóstico para pacientes con STAD y está vinculado a la inmunización de STAD.

Comprehensive Analysis of CLCA1 Expression, Immune Infiltration and Immune Checkpoints in Colon Adenocarcinoma / Análisis Completo de la Expresión de CLCA1, Infiltración Inmune y Puntos de Control Inmunológico en Colonadenocarcinoma

SUMMARY: Colon adenocarcinoma (COAD) is a prevalent disease worldwide, known for its high mortality and morbidity rates. Despite this, the extent of investigation concerning the correlation between COAD's CLCA1 expression and immune cell infiltration remains insufficient. This study seeks to examine the expression and prognosis of CLCA1 in COAD, along with its relationship to the tumor immune microenvironment. These findings will offer valuable insights for clinical practitioners and contribute to the existing knowledge in the field. In order to evaluate the prognostic significance of CLCA1 in individuals diagnosed with colorectal cancers, we conducted a comprehensive analysis using univariate and multivariate Cox regression models along with receiver operating characteristic curve (ROC) analysis. This study was performed on the patient data of COAD obtained from The Cancer Genome Atlas (TCGA) database. Nomograms were developed to anticipate CLCA1 prognostic influence. Furthermore, the CLCA1 association with tumor immune infiltration, immune checkpoints, immune checkpoint blockade (ICB) response, interaction network, and functional analysis of CLCA1-related genes was analyzed. We found that Colon adenocarcinoma tissues significantly had decreased CLCA1 expression compared to healthy tissues. Furthermore, the study revealed that the group with high expression of CLCA1 demonstrated a significantly higher overall survival rate (OS) as compared to the group with low expression. Multivariate and Univariate Cox regression analysis revealed the potential of CLCA1 as a standalone risk factor for COAD. These results were confirmed using nomograms and ROC curves. In addition, protein-protein interaction (PPI) network analysis and functional gene enrichment showed that CLCA1 may be associated with functional activities such as pancreatic secretion, estrogen signaling and cAMP signaling, as well as with specific immune cell infiltration. Therefor, as a new independent predictor and potential biomarker of COAD, CLCA1 plays a crucial role in the advancement of colon cancer.

El adenocarcinoma de colon (COAD) es una enfermedad prevalente a nivel mundial, conocida por sus altas tasas de mortalidad y morbilidad. Sin embargo, el alcance de la investigación sobre la correlación entre la expresión de CLCA1 de COAD y la infiltración de células inmunes sigue siendo insuficiente. Este estudio busca examinar la expresión y el pronóstico de CLCA1 en COAD, junto con su relación con el microambiente inmunológico del tumor. Estos hallazgos ofrecerán conocimientos valiosos para los profesionales clínicos y contribuirán al conocimiento existente en el campo. Para evaluar la importancia de pronóstico de CLCA1 en personas diagnosticadas con cáncer colorrectal, realizamos un análisis exhaustivo utilizando modelos de regresión de Cox univariados y multivariados junto con un análisis de la curva característica operativa del receptor (ROC). Este estudio se realizó con los datos de pacientes de COAD obtenidos de la base de datos The Cancer Genome Atlas (TCGA). Se desarrollaron nomogramas para anticipar la influencia pronóstica de CLCA1. Además, se analizó la asociación de CLCA1 con la infiltración inmunitaria tumoral, los puntos de control inmunitarios, la respuesta de bloqueo de los puntos de control inmunitarios (ICB), la red de interacción y el análisis funcional de genes relacionados con CLCA1. Descubrimos que los tejidos de adenocarcinoma de colon tenían una expresión significativamente menor de CLCA1 en comparación con los tejidos sanos. Además, el estudio reveló que el grupo con alta expresión de CLCA1 demostró una tasa de supervivencia general (SG) significativamente mayor en comparación con el grupo con baja expresión. El análisis de regresión de Cox multivariado y univariado reveló el potencial de CLCA1 como factor de riesgo independiente de COAD. Estos resultados se confirmaron mediante nomogramas y curvas ROC. Además, el análisis de la red de interacción proteína- proteína (PPI) y el enriquecimiento de genes funcionales mostraron que CLCA1 puede estar asociado con actividades funcionales como la secreción pancreática, la señalización de estrógenos y la señalización de AMPc, así como con la infiltración de células inmunes específicas. Por lo tanto, como nuevo predictor independiente y biomarcador potencial de COAD, CLCA1 desempeña un papel crucial en el avance del cáncer de colon.

TTYH3 is a prognostic biomarker and associates with immune cell infiltrations of lung adenocarcinoma / TTYH3 es un biomarcador pronóstico y se asocia con infiltraciones de células inmunitarias del adenocarcinoma de pulmón

SUMMARY: We investigated Tweety Family Member 3 (TTYH3) level in lung adenocarcinoma (LUAD) and its relationship with immune infiltration in tumors by bioinformatics. Differential expressions of TTYH3 in lung cancer were analyzed with Oncomine, TIMER, GEO, UALCAN and HPA. Relationship of TTYH3 mRNA/protein levels with clinical parameters was analyzed by UALCAN. Co-expressed genes of TTYH3 in LUAD were analyzed using Cbioportal. Its relationship with LUAD prognosis was analyzed by Kaplan-Meier plotter. GO and KEGG analysis were performed. Correlation between TTYH3 and tumor immune infiltration were tested by TIMER, TISIDB and GEPIA. We found that TTYH3 was significantly increased in LUAD tissues. TTYH3 high expression was closely related to poor overall survival, post progression survival and first progression in LUAD patients. TTYH3 mRNA/protein levels were significantly associated with multiple pathways. Specifically, TTYH3 up-regulation was mostly related to biological regulation, metabolic process, protein blinding, extracellular matrix organization and pathways in cancer. Moreover, TTYH3 was positively associated with immune cell infiltration in LUAD. Finally, TTYH3 was highly expressed in LUAD as revealed by meta-analysis. TTYH3 is closely related to the prognosis of LUAD and immune cell infiltration, and it can be used as a prognostic biomarker for LUAD and immune infiltration.

Investigamos por bioinformática el nivel de Tweety Family Member 3 (TTYH3) con adenocarcinoma de pulmón (LUAD) y su relación con la infiltración inmune en tumores. Las expresiones diferenciales de TTYH3 en cáncer de pulmón se analizaron con Oncomine, TIMER, GEO, UALCAN y HPA. Con UALCAN se analizó la relación de los niveles de ARNm/proteína de TTYH3 con los parámetros clínicos. Los genes coexpresados de TTYH3 en LUAD se analizaron utilizando Cbioportal. Su relación con el pronóstico LUAD se analizó mediante plotter de Kaplan- Meier. Se realizaron análisis GO y KEGG. TIMER, TISIDB y GEPIA probaron la correlación entre TTYH3 y la infiltración inmune tumoral. Encontramos que TTYH3 aumentó significativamente en los tejidos LUAD. La alta expresión de TTYH3 estuvo estrechamente relacionada con una supervivencia general deficiente, supervivencia posterior a la progresión y primera progresión en pacientes con LUAD. Los niveles de ARNm/ proteína de TTYH3 se asociaron significativamente con múltiples vías. Específicamente, la regulación positiva de TTYH3 se relacionó principalmente con la regulación biológica, el proceso metabólico, el cegamiento de proteínas, la organización de la matriz extracelular y las vías en el cáncer. Además, TTYH3 se asoció positivamente con la infiltración de células inmunitarias en LUAD. Finalmente, TTYH3 se expresó altamente en LUAD como lo reveló el metanálisis. TTYH3 está estrechamente relacionado con el pronóstico de LUAD y la infiltración de células inmunitarias, y se puede utilizar como biomarcador pronóstico para LUAD y la infiltración de células inmunitarias.

Tezacaftor-ivacaftor para o tratamento de pacientes com fibrose cística com 12 anos de idade ou mais com mutação F508del do gene CFTR em homozigose ou com mutação F508del e uma das seguintes mutações: P67L, D110H, R117C, L206W, R352Q, A455E, D579G, 711+3A→G, S945L, S977F, R1070W, D1152H, 2789+5G→A, 3272-26A→G, e 3849+10kbC→T: [maio de 2022] / Tezacaftor-ivacaftor for the treatment of cystic fibrosis patients 12 years of age and older with F508del mutation of the CFTR gene in homozygous or F508del mutation and one of the following mutations: P67L, D110H, R117C, L206W, R352Q, A455E, D579G, 711+3A→G, S945L, S977F, R1070W, D1152H, 2789+5G→A, 3272-26A→G, and 3849+10kbC→T: [May 2022]

INTRODUÇÃO: A Fibrose Cística é uma doença grave e rara, que comete vários sistemas orgânicos com repercussão direta na qualidade de vida de pacientes e familiares, bem como reduz significativamente a sobrevida dos portadores da enfermidade. Tezacaftor-ivacaftor têm mecanismos de ação complementares. Tezacaftor facilita o processamento celular e o tráfico de formas normais e mutantes de CFTR, para aumentar a quantidade de proteína CFTR madura enviada à superfície celular. O ivacaftor é um potencializador da proteína CFTR que aumenta a probabilidade de abertura do canal na superfície da célula para melhorar o transporte de cloreto. Para a atividade adequada de ivacaftor, a proteína CFTR deve estar presente na superfície da célula. O ivacaftor pode aumentar a quantidade de proteína CFTR na superfície da célula levada pelo tezacaftor, levando a um aumento adicional do transporte de cloreto, quando comparado a qualquer substância ativa sozinha. O efeito combinado do tezacaftor e do ivacaftor é o aumento da quantidade e função da proteína CFTR na superfície celular, resultando no aumento do transporte de cloreto. PERGUNTA: Tezacaftor-ivacaftor é efica

Tezacaftor-ivacaftor para o tratamento de pacientes com fibrose cística com 12 anos de idade ou mais com mutação F508del do gene CFTR em homozigose ou com mutação F508del e uma das seguintes mutações: P67L, D110H, R117C, L206W, R352Q, A455E, D579G, 711+3A→G, S945L, S977F, R1070W, D1152H, 2789+5G→A, 3272-26A→G, e 3849+10kbC→T: [fev. 2022] / Tezacaftor-ivacaftor for the treatment of cystic fibrosis patients 12 years of age and older with a homozygous F508del mutation of the CFTR gene or with an F508del mutation and one of the following mutations: P67L, D110H, R117C, L206W, R352Q, A455E, D579G, 711+3A→G, S945L, S977F, R1070W, D1152H, 2789+5G→A, 3272-26A→G, and 3849+10kbC→T: [Feb. 2022]

INTRODUÇÃO: A Fibrose Cística é uma doença grave e rara, que acomete vários sistemas orgânicos com repercussão direta na qualidade de vida de pacientes e familiares, bem como reduz significativamente a sobrevida dos portadores da enfermidade. Tezacaftor-ivacaftor têm mecanismos de ação complementares. Tezacaftor facilita o processamento celular e o tráfico de formas normais e mutantes de CFTR, para aumentar a quantidade de proteína CFTR madura enviada à superfície celular. O ivacaftor é um potencializador da proteína CFTR que aumenta a probabilidade de abertura do canal na superfície da célula para melhorar o transporte de cloreto. Para a atividade adequada de ivacaftor, a proteína CFTR deve estar presente na superfície da célula. O ivacaftor pode aumentar a quantidade de proteína CFTR na superfície da célula levada pelo tezacaftor, levando a um aumento adicional do transporte de cloreto, quando comparado a qualquer substância ativa sozinha. O efeito combinado do tezacaftor e do ivacaftor é o aumento da quantidade e função da proteína CFTR na superfície celular, resultando no aumento do transporte de cloreto. TECNOLOGIA: Tezacaftor-ivacaftor (Symdeko®). PERGUNTA: Tezacaftor-ivacaftor é eficaz,seguro e custo-efetivo no tratamento de FC homozigótica para a mutação F508del ou heterozigótica para essa mutação e com uma outra mutação no gene CFTR responsivo ao tezacaftor-ivacaftor em pacientes com 12 anos de idade ou mais, quando comparado à terapia de suporte atualmente disponível no SUS? EVIDÊNCIAS CLÍNICAS: Dois ECR duplo cegos (EVOLVE e EXPAND) forneceram evidências sobre a eficácia e segurança do tezacaftor-ivacaftor em pacientes com FC com idade ≥ 12 anos que tenham duas cópias da mutação F508del, ou que tenham uma cópia da mutação F508del e pelo menos uma das seguintes mutações no gene da FC: P67L, D110H, R117C, L206W, R352Q, A455E, D579G, 711+3A→G, S945L, S977F, R1070W, D1152H, 2789+5G→A, 3272-26A→G, e 3849+10kbC→T. Tezacaftor-ivacaftor proporcionou melhora no escore do domínio respiratório do CFQ-R até a semana 24 de 5,1 pontos (IC95%: 3,2-7,0) e a alteração média da linha de base do estudo para a média da semana 4 e semana 8 foi de 11,1 (IC95%: 8,7-13,6; p<0,001) pontos. Houve melhora na função respiratória no estudo EVOLVE comparado ao placebo (diferença média de quadrados mínimos ao longo de 24 semanas de 4,0 pontos percentuais; IC 95%, 3,1-4,8; p<0,001) e no estudo EXPAND, a diferença média dos mínimos quadrados desde o início do estudo até a semana 4 e semana 8 foi de 6,8 (IC95%: 5,7-7,8) pontos percentuais (p<0,001) versus ivacaftor. Tezacaftor-ivacaftor também proporcionou 35% menos risco de ocorrência de exacerbações pulmonares no estudo EVOLVE com RR = 0,65 (IC 95%: 0,48-0,88; p=0,005) e de 46% menos risco no estudo EXPAND com RR = 0,54 (IC 95%: 0,26-1,13; p=0,10). Em relação ao estado nutricional avaliado por meio do IMC, não foram observadas diferenças estatisticamente significativas. A concentração de cloreto no suor foi reduzida em 10,1 mmol/L no estudo EVOLVE (IC95%; -11,4 a -8,8) e em comparação com aqueles que receberam placebo: tezacaftor-ivacaftor, -9,5 mmol/L (IC95%: -11,7, -7,3; p<0,001) e versus ivacaftor foi de -5,1 mmol (IC95%: -7,0 a -3,1; p<0,001) no estudo EXPAND. Não foram identificados óbitos nos estudos e a frequência de eventos adversos foi menor nos pacientes do grupo tezacaftorivacaftor comparado a ivacaftor isolado ou placebo. A qualidade da evidência foi considerada moderada para todos os desfechos avaliados de acordo com a ferramenta GRADE. AVALIAÇÃO ECONÔMICA: O demandante apresentou um modelo de microssimulação para avaliar a razão de custoefetividade incremental (RCEI) com o uso, durante toda a vida, de tezacaftor-ivacaftor em combinação ao tratamento padrão para pacientes com FC com idade ≥12 anos homozigotos para a mutação F508del do gene CFTR (F/F) ou heterozigotos para a mutação F508del e uma segunda mutação associada à atividade residual de CFTR (F/RF), em comparação com o tratamento padrão isolado no SUS. Observou-se que tezacaftor-ivacaftor resultou em 7,87 anos de vida (AV) adicionais não descontados e 2,055 QALY incrementais descontados, culminando em uma RCEI de R$ 1.549.120,03/AV ganho e de R$ 1.580.752,23/QALY adicional. Destaca-se que os valores empregados podem ter sido subestimados por terem considerado a isenção de impostos, portanto, a RCEI pode ser superior, variando de 18% (somente ICMS) até 32,3% (incidência de todos os tributos). Além disso, em diferentes cenários com a variação de parâmetros, como descontos e componentes de custo, a RCEI da população total (ponderada) variou de R$ 551.274,00 a R$ 1.745.304,41. Nas análises de sensibilidade determinística univariada, os parâmetros que mais afetaram a RCEI foram a redução do declínio de ppVEF1, a adesão ao tratamento após o período de acompanhamento dos ensaios clínicos e aos valores de utilidade por gravidade da doença. A partir do diagrama de custo-efetividade da análise de sensibilidade probabilística, observou-se que tezacaftor-ivacaftor é consistentemente mais eficaz e mais caro em comparação com o tratamento padrão isoladamente. ANÁLISE DE IMPACTO ORÇAMENTÁRIO: Para se estimar a população elegível ao tezacaftor-ivacaftor no modelo de impacto orçamentário, foram utilizados dados do DATASUS com os CIDs de FC e os percentuais advindos de dados epidemiológicos no Brasil, considerado a genotipagem e a prevalência das mutações com indicação para o medicamento. Assim, estimouse que a incorporação de tezacaftor-ivacaftor no SUS resultará em um impacto orçamentário incremental acumulado de R$ 592.270.679,72 em cinco anos. Entretanto, destaca-se que os valores podem estar subestimados por ter sido considerada a isenção de impostos, portanto, um acrescimento de 18% a 32,3% pode fazer com que o impacto incremental varie de R$ 698.879.402,07 a R$ 783.574.109,27, no acumulado de cinco anos. MONITORAMENTO DO HORIZONTE TECNOLÓGICO: Foram encontrados os medicamentos elexacaftor (em combinação com tezacaftor e ivacaftor) e VX-121 (em combinação com tezacaftor e deutivacaftor), ambos moduladores de CFTR, sendo que a associação elexacaftor + tezacaftor + ivacaftor apresenta-se sem registro na ANVISA, constando registro na agência europeia (EMA) datada de 2020 e na agência norte americana (FDA) em 2019. Em setembro de 2020, esta tecnologia foi avaliada na agência canadense CADTH, recebendo recomendação favorável mediante atendimento de condições específicas. Para a associação de VX-121 + tezacaftor + deutivacaftor, não há ainda registros em nenhuma das três agências referidas e o estudo clínico ainda está em fase de recrutamento. CONSIDERAÇÕES FINAIS: As evidências selecionadas, consideradas de qualidade moderada, demonstraram respostas superiores com o uso da associação tezacaftor-ivacaftor, quando comparada a placebo ou ivacaftor isoladamente, em todos os desfechos avaliados, à exceção no ganho de IMC. A análise de custo-efetividade realizada demonstrou uma RCEI de R$ 1.549.120,03/AV ganho e de R$ 1.580.752,23/QALY adicional, variando a depender dos parâmetros considerados. Já o impacto orçamentário incremental, foi estimado em R$ 592.270.679,72, no acumulado de cinco anos, podendo variar entre R$ 698.879.402,07 e R$ 783.574.109,27 em cinco anos, quando considerada a incidência de impostos. PERSPECTIVA DO PACIENTE: A chamada pública de número 49/2021 para participar da Perspectiva do Paciente foi aberta de 13/08/2021 a 27/08/2021 e nove pessoas se inscreveram. A indicação dos representantes titular e suplente para fazer o relato da experiência foi feita a partir de definição consensual por parte do grupo de inscritos. No relato, a participante descreveu como o uso do medicamento afetou positivamente sua qualidade de vida ao promover redução significativa da dificuldade de respirar, do cansaço, da produção de secreção e de manifestações intestinais. RECOMENDAÇÃO PRELIMINAR DA CONITEC: Diante do exposto, o Plenário da Conitec, em sua 105ª Reunião Ordinária, no dia 09 de fevereiro de 2022, deliberou que a matéria fosse disponibilizada em Consulta Pública com recomendação preliminar desfavorável à incorporação no SUS de tezacaftor-ivacaftor no tratamento de pacientes com fibrose cística (FC) com 12 anos de idade ou mais que tenham duas cópias da mutação F508del, ou que tenham uma cópia da mutação F508del e pelo menos uma das seguintes mutações no gene da FC: P67L, D110H, R117C, L206W, R352Q, A455E, D579G, 711+3A→G, S945L, S977F, R1070W, D1152H, 2789+5G→A, 3272-26A→G, e 3849+10kbC→T, foi considerada que há fragilidade na evidência científica apresentada e elevado impacto orçamentário. A matéria foi disponibilizada em consulta pública.

Hematopoietic stem cell transplantation in a patient with osteopetrosis and mutation in CLCN7: long-term follow-up / Trasplante de células progenitoras hematopoyéticas en un paciente con osteopetrosis y mutación en CLCN7: seguimiento a largo plazo

Abstract Background: Osteopetrosis is a rare hereditary bone dysplasia characterized by insufficient osteoclast activity that results in increased bone mineral density. Hematopoietic stem cell transplantation (HSCT) can reverse skeletal abnormalities and restore hematopoiesis. Case report: We present the case of a 3-year and 2-month-old male patient with the diagnosis of osteopetrosis. The patient underwent allogeneic HSCT (Allo-HSCT) using 100% compatible bone marrow from a related donor and received a myeloablative conditioning regimen and a CD34 cell dose (4.7 × 107/kg). In the early post-transplant, frequent complications such as pneumonitis, hypercalcemia, and hyperphosphatemia ocurred. With a suitable granulocytic graft and chimerism of 100%, it was considered a successful transplant. However, the patient showed a delayed platelet graft treated with a platelet-stimulating factor for 6 months. The patient is currently disease-free, outpatient follow-up, with no data on graft-versus-host disease, and no progressive neurological damage. Conclusions: Osteopetrosis is a childhood disease that requires clinical suspicion and early diagnosis. HSCT is necessary at an early age to prevent disease progression and sensorineural, hematological, and endocrinological functions damage that can lead to death.

Resumen Introducción: La osteopetrosis es una displasia ósea hereditaria poco común, caracterizada por una actividad osteoclástica deficiente que aumenta la densidad mineral ósea. Se considera que el trasplante de células progenitoras hematopoyéticas (TCPH) puede revertir las anormalidades esqueléticas y restaurar la hematopoyesis. Caso clínico: Se presenta el caso de un paciente de sexo masculino, de 3 años y 2 meses de edad, con diagnóstico tardío de osteopetrosis. Se realizó un TCPH alogénico de donador relacionado 100% compatible con médula ósea. Se utilizaron un régimen de acondicionamiento mieloablativo y una dosis celular de CD34 de 4.7 × 107/kg de peso. En el postrasplante temprano, el paciente desarrolló complicaciones como neumonitis, hipercalcemia e hiperfosfatemia. Con un injerto granulocítico adecuado y quimerismo del 100% se consideró un trasplante exitoso. Sin embargo, el paciente presentó retraso en el injerto plaquetario, por lo que se administró factor estimulante de plaquetas por 6 meses. Actualmente el paciente se encuentra libre de enfermedad, en seguimiento ambulatorio, sin datos de enfermedad del injerto contra el hospedero y con pruebas de neurodesarrollo sin deterioro neurológico progresivo. Conclusiones: La osteopetrosis es una enfermedad infantil que requiere una sospecha clínica y un diagnóstico temprano, ya que es necesario un TCPH a corta edad como tratamiento para evitar la progresión de la enfermedad y el deterioro de las funciones neurosensoriales, hematológicas y endocrinológicas que puede derivar en la defunción del paciente.

Modification in clic4 expression is associated with p53, tgf-ß, tnf-α and myofibroblasts in lip carcinogenesis

Abstract Chloride intracellular channel-4 (CLIC4) is regulated by p53 and tumor necrosis factor-α (TNF-α), it is linked to the increase of transforming growth factor-β (TGF-β), and myofibroblastic differentiation in skin carcinogenesis. This study analyzed the immunoexpression of CLIC4, p53, TGF-β, TNF-α, and α-SMA in 50 actinic cheilitis (AC) and 50 lower lip squamous cell carcinoma (LLSCC). AC and LLSCC immunoexpression were categorized as score 1 (<5% positive cells), 2 (5-50%) or 3 (>50%). For CLIC4, nuclear and cytoplasmic immunostaining of epithelial cells was considered individually. For morphologic analysis, the World Health Organization criteria were used to epithelial dysplasia grade of ACs, and Bryne grading of malignancy system was applied for LLSCC. Higher nuclear CLIC4 (CLIC4n) and TGF-β were observed in ACs with low-risk of transformation, while cytoplasmic CLIC4 (CLIC4c), p53 and TNF-α were higher in the high-risk cases (p<0.05). In LLSCCs, CLIC4c was higher in cases with lymph node metastasis, advanced clinical stages, and histological high-grade malignancy. p53 expression was higher in high-grade LLSCCs, whereas TGF-β decreased as the clinical stage and morphological grade progressed (p<0.05). ACs showed an increased expression of CLIC4n and TGF-β, while CLIC4c and α-SMA were higher in LLSCCs (p<0.0001). Both lesions showed negative correlation between CLIC4n and CLIC4c, while in LLSCCs, negative correlation was also verified between CLIC4c and p53, as well as CLIC4c and TGF-β (p<0.05). Change of CLIC4 from the nucleus to cytoplasm and alterations in p53, TGF-β, TNF-α, and α-SMA expression are involved in lip carcinogenesis.

Resumo O canal intracelular de cloreto 4 (CLIC4) é regulado pela p53 e fator de necrose tumoral α (TNF-α) e está relacionado ao aumento do fator de crescimento transformador β (TGF-β) e na diferenciação miofibroblástica na carcinogênese cutânea. Este estudo analisou a imunoexpressão de CLIC4, p53, TGF-β, TNF-α e α-SMA em 50 queilites actínicas (QA) e 50 carcinomas de células escamosas de lábio inferior (CCELI). A imunoexpressão da QA e CCELI foram categorizadas em escore 1 (<5% de células positivas), 2 (5-50%) ou 3 (>50%). Para CLIC4, a imunomarcação nuclear e citoplasmática das células epiteliais foi considerada separadamente. Para análise morfológica, foram utilizados os critérios da Organização Mundial da Saúde para a gradação das displasias epiteliais nas QAs, e o sistema de gradação de malignidade de Bryne foi utilizado para os casos de CCELIs. Alta imunoexpressão de CLIC4 nuclear (CLIC4n) e TGF-β foi observada em QA de baixo risco de transformação, enquanto CLIC4 citoplasmática (CLIC4c), p53 e TNF-α foram elevadas nos casos de alto risco (p<0.05). No CCELI, a imunoexpressão de CLIC4c foi maior em caos com metástase linfonodal, estágio clínico avançado e alto grau histológico de malignidade. A expressão de p53 foi elevada em CCELI de alto grau, enquanto o TGF-β diminuiu à medida que o estádio clínico e o grau morfológico progrediram (p<0.05). QAs exibiram uma elevada expressão de CLIC4n e TGF-β, enquanto o CLIC4c e α-SMA foram elevados em CCELIs (p<0.0001). Ambas as lesões mostraram correlação negativa entre CLIC4n e CLIC4c, enquanto nos CCELIs, também se verificou correlação negativa entre CLIC4c e p53, assim como entre CLIC4c e TGF-β (p<0.05). Alteração do CLIC4 do núcleo para o citoplasma e alterações na expressão de p53, TGF-β, TNF-α, e α-SMA estão envolvidas na carcinogênese labial.

Progress of research on the role of CLCNKB gene in classical Bartter syndrome / 中华医学遗传学杂志

Bartter syndrome is an inherited metabolic disorder characterized by hypokalemic alkalosis and high rennin-angiotensin-aldosteronism which can occur at all ages but mainly in childhood. Classical Bartter syndrome is caused by loss-of-function variants in the gene encoding basolateral chloride channel ClC-Kb (CLCNKB), which is a common type of Bartter syndrome characterized with diverse clinical manifestations ranging from severe to very mild. This article reviews the function and mechanism of CLCNKB variants in Chinese population and the genotype-phenotype correlation of CLCNKB variants in classical Bartter syndrome.

Cystic fibrosis lung disease: Current perspectives

Cystic fibrosis (CF) is an autosomal recessive disease caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR). These mutations alter the synthesis, processing, function, or half-life of CFTR, the main chloride channel expressed in the apical membrane of epithelial cells in the airway, intestine, pancreas, and reproductive tract. Lung disease is the most critical manifestation of CF. It is characterized by airway obstruction, infection, and inflammation that lead to fatal tissue destruction, which causes most CF morbidity and mortality. This article reviews the pathophysiology of CF, recent animal models, and current treatment of CF.

Transportadores de iones en pulmón: Uso como dianas terapéuticas / Ion transporters in the lungs. Use as therapeutic targets

Los canales de cloruros, de sodio, de bicarbonato y los de agua (aquaporinas) se coordinan para mantener la cubierta líquido superficial de las vías respiratorias, que es necesaria para el aclaramiento mucociliar. El mecanismo general para el transporte de electrolitos y agua depende principalmente de la expresión diferencial y distribución de los transportadores y bombas de iones. Los iones y el agua se mueven a través de las vía paracelular o transcelular. La ruta transcelular del transporte de electrolitos requiere un transporte activo (dependiente de ATP) o pasivo (siguiendo gradientes electroquímicos) de iones. La ruta paracelular es un proceso pasivo que está controlado, en última instancia, por los gradientes electroquímicos transepiteliales predominantes. La fibrosis quística es una enfermedad hereditaria que se produce por mutaciones en el gen que codifica la proteína reguladora de la conductibilidad transmembrana de la fibrosis quística (CFTR) que actúa como un canal de cloro y cumple funciones de hidratación del líquido periciliar y mantenimiento del pH luminal. La disfunción del canal de cloro en el epitelio respiratorio determina una alteración en las secreciones bronquiales, con aumento de su viscosidad y alteración de la depuración mucociliar y que asociado a procesos infecciosos puede conducir a daño pulmonar irreversible. La disfunción del CFTR, también se ha visto implicado en la patogénesis de la pancreatitis aguda, en la enfermedad pulmonar obstructiva crónica y la hiperreactividad en el asma. Existen fármacos que aprovechan los mecanismos fisiológicos en el transporte de iones, con un objetivo terapéutico.

The chloride channels, sodium and bicarbonate channels, and aquaporin water channels are coordinated to maintain the airway surface liquid that is necessary for mucociliary clearance. The general mechanism for the transport of electrolytes and fluids depends mainly on the differential expression and distribution of ion transporters and pumps. Ions and water move through the paracellular or transcellular pathways. The transcellular route of electrolyte transport requires an active transport (dependent on ATP) or passive (following electrochemical gradients) of ions. The paracellular pathway is a passive process that is ultimately controlled by the predominant transepithelial electrochemical gradients. Cystic fibrosis is a hereditary disease that is produced by mutations in the gene that encode cystic fibrosis transmembrane conductance regulatory protein (CFTR) that acts as a chloride channel and performs functions of hydration of periciliary fluid and maintenance of luminal pH. The dysfunction of the chlorine channel in the respiratory epithelium determines an alteration in the bronchial secretions, with an increase in its viscosity and alteration of the mucociliary clearance and that associated with infectious processes can lead to irreversible lung damage. CFTR dysfunction has also been implicated in the pathogenesis of acute pancreatitis, chronic obstructive pulmonary disease, and bronchial hyperreactivity in asthma. There are drugs that exploit physiological mechanisms in the transport of ions with a therapeutic objective.

Colonic Dysmotility in Murine Partial Colonic Obstruction Due to Functional Changes in Interstitial Cells

BACKGROUND/AIMS: Interstitial cells play important roles in gastrointestinal (GI) neuro-smooth muscle transmission. The underlying mechanisms of colonic dysmotility have not been well illustrated. We established a partial colon obstruction (PCO) mouse model to investigate the changes of interstitial cells and the correlation with colonic motility. METHODS: Western blot technique was employed to observe the protein expressions of Kit, platelet-derived growth factor receptor-α (Pdgfra), Ca²⁺-activated Cl⁻ (Ano1) channels, and small conductance Ca²⁺- activated K⁺ (SK) channels. Colonic migrating motor complexes (CMMCs) and isometric force measurements were employed in control mice and PCO mice. RESULTS: PCO mice showed distended abdomen and feces excretion was significantly reduced. Anatomically, the colon above the obstructive silicone ring was obviously dilated. Kit and Ano1 proteins in the colonic smooth muscle layer of the PCO colons were significantly decreased, while the expression of Pdgfra and SK3 proteins were significantly increased. The effects of a nitric oxide synthase inhibitor (L-NAME) and an Ano1 channel inhibitor (NPPB) on CMMC and colonic spontaneous contractions were decreased in the proximal and distal colons of PCO mice. The SK agonist, CyPPA and antagonist, apamin in PCO mice showed more effect to the CMMCs and colonic smooth muscle contractions. CONCLUSIONS: Colonic transit disorder may be due to the downregulation of the Kit and Ano1 channels and the upregulation of SK3 channels in platelet-derived growth factor receptor-α positive (PDGFRα⁺) cells. The imbalance between interstitial cells of Cajal-Ano1 and PDGFRα-SK3 distribution might be a potential reason for the colonic dysmotility.

Colonic Transit Disorder Mediated by Downregulation of Interstitial Cells of Cajal/Anoctamin-1 in Dextran Sodium Sulfate-induced Colitis Mice

BACKGROUND/AIMS: Interstitial cells of Cajal (ICC) and their special calcium-activated chloride channel, anoctamin-1 (ANO1) play pivotal roles in regulating colonic transit. This study is designed to investigate the role of ICC and the ANO1 channel in colonic transit disorder in dextran sodium sulfate (DSS)-treated colitis mice. METHODS: Colonic transit experiment, colonic migrating motor complexes (CMMCs), smooth muscle spontaneous contractile experiments, intracellular electrical recordings, western blotting analysis, and quantitative polymerase chain reaction were applied in this study. RESULTS: The mRNA and protein expressions of c-KIT and ANO1 channels were significantly decreased in the colons of DSS-colitis mice. The colonic artificial fecal-pellet transit experiment in vitro was significantly delayed in DSS-colitis mice. The CMMCs and smooth muscle spontaneous contractions were significantly decreased by 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB), an ANO1 channel blocker, and NG-Nitro-L-arginine methyl ester hydrochloride (L-NAME), an inhibitor of nitric oxide synthase activity, in DSS-colitis mice compared with that of control mice. Intracellular electrical recordings showed that the amplitude of NPPB-induced hyperpolarization was more positive in DSS-colitis mice. The electric field stimulation-elicited nitric-dependent slow inhibitory junctional potentials were also more positive in DSS-colitis mice than those of control mice. CONCLUSION: The results suggest that colonic transit disorder is mediated via downregulation of the nitric oxide/ICC/ANO1 signalling pathway in DSS-colitis mice.

Establishment and application of a cell model for LRRC8A physiological characteristic study / 生理学报

The aim of the present study was to establish a cell model of volume-regulated anion channel subunit LRRC8A and investigate the physiological characteristics of LRRC8A. The eukaryotic expression vectors of LRRC8A and YFP-H148Q/I152L were constructed and transfected into Fischer rat thyroid (FRT) cells by Lipofectamine 2000. The FRT cell lines co-expressing LRRC8A and YFP-H148Q/I152L were obtained by antibiotic screening. The expression of LRRC8A and YFP-H148Q/I152L in FRT cells was detected by the inverted fluorescence microscope. The fluorescence quenching kinetic experiment was done to verify the function and effectiveness of the cell model. Then the cell model was utilized to study the physiological characteristics of LRRC8A, such as the characteristics of anion transport, the opening of LRRC8A by osmotic pressure, the effect of anion transport velocity, and the effect of chloride channel inhibitors on LRRC8A anion channel. The results of the inverted fluorescence microscope showed that LRRC8A was expressed on the cell membrane and YFP-H148Q/I152L was expressed in the cytoplasm. The results of fluorescence quenching kinetic test showed that under the condition of low osmotic state, LRRC8A could transport some kinds of anions, such as iodine and chloride ions. Osmotic pressure played a key role in the regulation of LRRC8A volume-regulated anion channel opening. Chloride channel inhibitors inhibited ion transport of LRRC8A channel in a dose-dependent manner. It is suggested that LRRC8A has the characteristics of classic volume-regulated anion channels by using the cell model of FRT cells co-expressing LRRC8A and YFP-H148Q/I152L.

EF-hand like Region in the N-terminus of Anoctamin 1 Modulates Channel Activity by Ca²⁺ and Voltage

Anoctamin1 (ANO1) also known as TMEM16A is a transmembrane protein that functions as a Ca²⁺ activated chloride channel. Recently, the structure determination of a fungal Nectria haematococca TMEM16 (nhTMEM16) scramblase by X-ray crystallography and a mouse ANO1 by cryo-electron microscopy has provided the insight in molecular architecture underlying phospholipid scrambling and Ca²⁺ binding. Because the Ca²⁺ binding motif is embedded inside channel protein according to defined structure, it is still unclear how intracellular Ca²⁺ moves to its deep binding pocket effectively. Here we show that EF-hand like region containing multiple acidic amino acids at the N-terminus of ANO1 is a putative site regulating the activity of ANO1 by Ca²⁺ and voltage. The EF-hand like region of ANO1 is highly homologous to the canonical EF hand loop in calmodulin that contains acidic residues in key Ca²⁺-coordinating positions in the canonical EF hand. Indeed, deletion and Ala-substituted mutation of this region resulted in a significant reduction in the response to Ca²⁺ and changes in its key biophysical properties evoked by voltage pulses. Furthermore, only ANO1 and ANO2, and not the other TMEM16 isoforms, contain the EF-hand like region and are activated by Ca²⁺. Moreover, the molecular modeling analysis supports that EF-hand like region could play a key role during Ca²⁺ transfer. Therefore, these findings suggest that EF-hand like region in ANO1 coordinates with Ca²⁺ and modulate the activation by Ca²⁺ and voltage.

Tetrabromobisphenol A Promotes the Osteoclastogenesis of RAW264.7 Cells Induced by Receptor Activator of NF-kappa B Ligand In Vitro

BACKGROUND: Tetrabromobisphenol A (TBBPA), one of the most widely used brominated flame-retardants, is a representative persistent organic pollutants group. Studies on TBBPA toxicity have been conducted using various target cells; however, few studies have investigated TBBPA toxicity in bone cells. Therefore, this study investigated the in vitro effects of TBBPA on osteoclasts, a cell type involved in bone metabolism. METHODS: RAW264.7 cells were cultured in medium containing 50 ng/mL receptor activator of nuclear factor kappa B ligand (RANKL) and varying concentrations of TBBPA. To evaluate the effects of TBBPA on the differentiation and function of osteoclasts, osteoclast-specific gene expression, tartrate-resistant acid phosphatase (TRAP) activity, bone resorbing activity, mitochondrial membrane potential (MMP) and mitochondrial superoxide were measured. RESULTS: The presence of 20 μM TBBPA significantly increased TRAP activity in RANKL-stimulated RAW264.7 cells, the bone resorbing activity of osteoclasts, and the gene expression of Akt2, nuclear factor of activated T-cells cytoplasmic 1, and chloride channel voltage-sensitive 7. However, TBBPA treatment caused no change in the expression of carbonic anhydrase II, cathepsin K, osteopetrosis-associated transmembrane protein 1, Src, extracellular signal-related kinase, GAB2, c-Fos, or matrix metalloproteinase 9. Furthermore, 20 μM TBBPA caused a significant decrease in MMP and a significant increase in mitochondrial superoxide production. CONCLUSION: This study suggests that TBBPA promotes osteoclast differentiation and activity. The mechanism of TBBPA-stimulated osteoclastogenesis might include increased expression of several genes involved in osteoclast differentiation and reactive oxygen species production.

Deficiency of Anoctamin 5/TMEM16E causes nuclear positioning defect and impairs Ca²⁺ signaling of differentiated C2C12 myotubes

Anoctamin 5 (ANO5)/TMEM16E belongs to a member of the ANO/TMEM16 family member of anion channels. However, it is a matter of debate whether ANO5 functions as a genuine plasma membrane chloride channel. It has been recognized that mutations in the ANO5 gene cause many skeletal muscle diseases such as limb girdle muscular dystrophy type 2L (LGMD2L) and Miyoshi muscular dystrophy type 3 (MMD3) in human. However, the molecular mechanisms of the skeletal myopathies caused by ANO5 defects are poorly understood. To understand the role of ANO5 in skeletal muscle development and function, we silenced the ANO5 gene in C2C12 myoblasts and evaluated whether it impairs myogenesis and myotube function. ANO5 knockdown (ANO5-KD) by shRNA resulted in clustered or aggregated nuclei at the body of myotubes without affecting differentiation or myotube formation. Nuclear positioning defect of ANO5-KD myotubes was accompanied with reduced expression of Kif5b protein, a kinesin-related motor protein that controls nuclear transport during myogenesis. ANO5-KD impaired depolarization-induced [Ca²⁺]i transient and reduced sarcoplasmic reticulum (SR) Ca²⁺ storage. ANO5-KD resulted in reduced protein expression of the dihydropyridine receptor (DHPR) and SR Ca²⁺-ATPase subtype 1. In addition, ANO5-KD compromised co-localization between DHPR and ryanodine receptor subtype 1. It is concluded that ANO5-KD causes nuclear positioning defect by reduction of Kif5b expression, and compromises Ca²⁺ signaling by downregulating the expression of DHPR and SERCA proteins.

Una nueva mutación de la enfermedad de Dent en un niño de 11 años con nefrolitiasis y nefrocalcinosis / A novel mutation of Dent's disease in an 11-year-old male with nephrolithiasis and nephrocalcinosis

La enfermedad de Dent es una tubulopatía recesiva ligada al cromosoma X caracterizada por proteinuria de bajo peso molecular (bpm), hipercalciuria, nefrocalcinosis o nefrolitiasis, disfunción tubular proximal e insuficiencia renal en la adultez. Las mujeres son portadoras y, en general, padecen una forma leve de la enfermedad. La progresión hacia la insuficiencia renal en estadio terminal se da entre los 30 y los 50 años de edad en el 30-80% de los varones afectados. A falta de un tratamiento dirigido al defecto molecular, en la actualidad, los pacientes con enfermedad de Dent reciben tratamientos complementarios orientados a prevenir la nefrolitiasis y la nefrocalcinosis. El caso que presentamos es el de un niño de 11 años con nefrocalcinosis y nefrolitiasis, en quien se detectó una nueva mutación en el gen CLCN5.

Dent's disease is a rare X-linked recessive tubulopathy characterized by low molecular weight (LMW) proteinuria, hypercalciuria, nephrolcalcinosis or nephrolithiasis, proximal tubular dysfunction and renal failure in adulthood. Females are carriers and usually mildly affected. Progression to endstage renal failure are at the 3rd-5th decades of life in 30-80% of affected males. In the absence of therapy targeting for the molecular defect, the current care of patients with Dent's disease is supportive, focusing on the prevention of nephrolithiasis and nephrocalcinosis. We present an 11-year-old child with nephrocalcinosis and nephrolithiasis caused by a new mutation at CLCN5 gene.

Phenotypic expression variability in Best Disease: a purpose of a series of cases / Variabilidade de expressão Fenotípica na Doença de Best: a propósito de uma série de casos

Abstract The objective of the following work is to document the phenotypic expression variability in Best Disease in first-degree relatives. The information was collected by assessing medical notes, interviewing the patient and obtaining photographic record of the diagnostic methods to which the patient was submitted. Data was analyzed along with a thorough review of the literature. A series of cases were reported in which the patient presenting the phenotypic characteristics of the disease has first degree relatives without ophthalmic findings during examination, but present an abnormal pattern on the electro-oculogram (EOG). Our article reveals the importance of electrophysiological exams in the diagnosis of Best vitelliform macular dystrophy, including the prevention of its clinical manifestation (autosomal dominant), providing concrete subsidies for genetic counseling.

Resumo O objetivo do presente trabalho é a documentação da variabilidade de expressão fenotípica da Doença de Best em parentes de primeiro grau. As informações foram obtidas por meio de revisão do prontuário, entrevista com o paciente e registro fotográfico dos métodos diagnósticos aos quais os pacientes foram submetidos. Dados foram analisados junto a uma extensa revisão da literatura. Relatamos uma série de casos, no qual o paciente que apresenta as alterações fenotípicas da doença tem familiares de primeiro grau sem alterações ao exame oftalmológico, porém os mesmos apresentam padrão anormal de eletro-oculograma (EOG). O nosso artigo revela a importância dos exames eletrofisiológicos no diagnóstico da distrofia macular viteliforme de Best, inclusive no que se refere à prevenção de sua manifestação clínica (autossômica dominante), fornecendo subsídios concretos para o aconselhamento genético.

Effects of chloride channels on hemolysis induced by puerarin injection / 中国应用生理学杂志

OBJECTIVE@#To observe the effects of blocking and activating chloride channels on hemolysis induced by puerarin injection in rabbits and to investigate the roles of chloride channels in hemolytic reaction induced by puerarin injection.@*METHODS@#Rabbit erythrocyte suspension was incubated with different concentrations of puerarin injection(0.75, 1.5, 3, 6, 12 mg/ml) at 37C for 6 hours. The cell imaging system was employed to observe whether puerarin injection induced hemolysis. The hemolysis rate was detected by microplate reader and flow cytometry. Effects of activating and closing chloride channels on the hemolysis induced by puerarin injection were explored.@*RESULTS@#Puerarin injection could induce the hemolysis of rabbit erythrocytes . In the range of 1.5 mg/ml~12 mg/ml, puerarin injection could induce hemolysis in a concentration-dependent manner (=3, <0.01). The chloride channel blockers tamoxifen (20 μmol/L) and ATP (10 mmol/L) significantly inhibited the hemolysis induced by puerarin injection (=3~5, <0.01). Application of low concentration ATP (50 μmol/L) to activate the chloride channel significantly increased puerarin injection induced hemolysis (=4, <0.01).@*CONCLUSIONS@#The hemolytic effect of puerarin injection is dose-dependent , and the activation of chloride channel is closely related to the hemolysis induced by puerarin injection.

Knockdown of Chloride Channel-3 Inhibits Breast Cancer Growth In Vitro and In Vivo / 한국유방암학회지

PURPOSE: Chloride channel-3 (ClC-3) is a member of the chloride channel family and plays a critical role in a variety of cellular activities. The aim of the present study is to explore the molecular mechanisms underlying the antitumor effect of silencing ClC-3 in breast cancer. METHODS: Human breast cancer cell lines MDA-MB-231 and MCF-7 were used in the experiments. Messenger RNA and protein expression were examined by quantitative real-time polymerase chain reaction and western blot analysis. Cell proliferation was measured by the bromodeoxyuridine method, and the cell cycle was evaluated using fluorescence-activated cell sorting. Protein interaction in cells was analyzed by co-immunoprecipitation. Tumor tissues were stained with hematoxylin-eosin and tumor burden was measured using the Metamorph software. RESULTS: Breast cancer tissues collected from patients showed an increase in ClC-3 expression. Knockdown of ClC-3 inhibited the secretion of insulin-like growth factor (IGF)-1, cell proliferation, and G1/S transition in breast cancer cells. In the mouse xenograft model of human breast carcinoma, tumor growth was significantly slower in animals injected with ClC-3-deficient cells compared with the growth of normal human breast cancer cells. In addition, silencing of ClC-3 attenuated the expression of proliferating cell nuclear antigen, Ki-67, cyclin D1, and cyclin E, as well as the activation of extracellular signal-regulated protein kinases (ERK) 1/2, both in vitro and in vivo. CONCLUSION: Together, our data suggest that upregulation of ClC-3 by IGF-1 contributes to cell proliferation and tumor growth in breast cancer, and ClC-3 deficiency suppresses cell proliferation and tumor growth via the IGF/IGF receptor/ERK pathway.