Stellera chamaejasme extract against multidrug resistance of breast cancer cell line MCF-7 / 中国中药杂志

This study explored the effect and underlying mechanism of Stellera chamaejasme extract(SCE) on multidrug resistance of breast cancer. The chemotherapy-sensitive breast cancer cell line MCF-7 and adriamycin(ADR)-resistant cell line MCF-7/ADR were used as experimental subjects. MTT assay was used to detect cell proliferation activity. Pi staining was used to detect the cell cycle. 4',6-Diamidino-2-phenylindole, dihydrochloride(DAPI) staining and flow cytometry were used to detect apoptosis. Dansylcadaverine(MDC) staining and GFP-LC3B-Mcherry adenovirus transfection were used to detect autophagy. The protein expression of Bcl-2, Bax, caspase-9, caspase-3, LC3B, p62, and Beclin-1 was detected by Western blot. The results showed that SCE could significantly inhibit the proliferation of both sensitive and resistant breast cancer cell lines. The drug resistance factor was 0.53, which was significantly lower than 59 of ADR. Meanwhile, the proportion of sensitive/resistant cells in the G_0/G_1 phase increased significantly after SCE treatment. In addition, DAPI staining showed that a series of apoptosis phenomena such as nuclear pyknosis, staining deepening, and nuclear fragmentation appeared in sensitive/resistant cell lines after SCE administration. Moreover, the results of flow cytometry double staining showed that the proportion of apoptotic cells in sensitive/resistant cell lines increased significantly after SCE administration. Besides, Western blot showed that the protein expression levels of caspase-3, caspase-9, and Bcl-2 significantly decreased and the expression level of Bax protein significantly increased in both breast cancer cell lines after SCE administration. Furthermore, SCE could also increase the positive fluorescent spots after MDC staining and yellow fluorescent spots after GFP-LC3B-mcherry transfection, and up-regulate the expression levels of autophagy-related proteins LC3B-Ⅱ, p62, and Beclin-1 in breast cancer cells. In summary, SCE may play the role of anti-multidrug resistance by blocking the cell cycle of breast cancer multidrug-resistant cells, blocking autophagy flow, and ultimately interfering with the apoptosis resistance of drug-resistant cells.

Efficacy and clinical outcome of chemotherapy and endocrine therapy as first-line treatment in patients with hormone receptor-positive HER2-negative metastatic breast cancer / 中华医学杂志(英文版)

BACKGROUND@#Endocrine therapy (ET) and ET-based regimens are the preferred first-line treatment options for hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (HR+/HER2- MBC), while chemotherapy (CT) is commonly used in clinical practice. The aim of this study was to investigate the efficacy and clinical outcome of ET and CT as first-line treatment in Chinese patients with HR+/HER2- MBC.@*METHODS@#Patients diagnosed with HR+/HER2-MBC between January 1st, 1996 and September 30th, 2018 were screened from the Chinese Society of Clinical Oncology Breast Cancer database. The initial and maintenance first-line treatment, progression-free survival (PFS), and overall survival (OS) were analyzed.@*RESULTS@#Among the 1877 included patients, 1215 (64.7%) received CT and 662 (35.3%) received ET as initial first-line treatment. There were no statistically significant differences in PFS and OS between patients receiving ET and CT as initial first-line treatment in the total population (PFS: 12.0 vs. 11.0 months, P = 0.22; OS: 54.0 vs . 49.0 months, P =0.09) and propensity score matched population. For patients without disease progression after at least 3 months of initial therapy, maintenance ET following initial CT (CT-ET cohort, n = 449) and continuous schedule of ET (ET cohort, n = 527) had longer PFS than continuous schedule of CT (CT cohort, n = 406) in the total population (CT-ET cohort vs. CT cohort: 17.0 vs . 8.5 months; P <0.01; ET cohort vs . CT cohort: 14.0 vs . 8.5 months; P <0.01) and propensity score matched population. OS in the three cohorts yielded the same results as PFS.@*CONCLUSIONS@#ET was associated with similar clinical outcome to CT as initial first-line treatment. For patients without disease progression after initial CT, switching to maintenance ET showed superiority in clinical outcome over continuous schedule of CT.

Effects of adjuvant trastuzumab on long-term survival of T1N0M0 stage human epidermal growth factor receptor 2 positive breast cancer: a real-world study / 中华肿瘤杂志

Objective: To investigate the prognosis impact of adjuvant trastuzumab treatment on human epidermal growth factor receptor 2 (HER-2) positive early breast cancer patients. Methods: A retrospective study was conducted, HER-2-positive T1N0M0 stage breast cancer patients who underwent surgery in the Affiliated Tumor Hospital of Xinjiang Medical University from January 2010 to December 2019 were divided into treatment group and control group according to whether they were treated with trastuzumab or not. Propensity score matching (PSM) was used to balance the confounding bias caused by differences in baseline characteristics between the two groups. Cox proportional hazards model was used to analyze the risk factors affecting disease-free survival (DFS). The Kaplan-Meier method was used to estimate the 3- and 5-year DFS and overall survival (OS) rates of the two groups before and after PSM. Results: There were 291 patients with HER-2 positive T1N0M0 stage breast cancer, including 21 cases in T1a (7.2%), 61 cases in T1b (21.0%), and 209 cases in T1c (71.8%). Before PSM, there were 132 cases in the treatment group and 159 cases in the control group, the 5-year DFS rate was 88.5%, and the 5-year OS rate was 91.5%. After PSM, there were 103 cases in the treatment group and 103 cases in the control group, the 5-year DFS rate was 86.0%, and the 5-year OS rate was 88.5%. Before PSM, there were significant differences in tumor size, histological grade, vascular invasion, Ki-67 index, postoperative chemotherapy or not and radiotherapy between the treatment group and the control group (P<0.05). After PSM, there were no significant difference in clinicopathological features between the treatment group and the control group (P>0.05). Multivariate analysis showed that histological grade (HR=2.927, 95 CI: 1.476, 5.805; P=0.002), vascular invasion (HR=3.410, 95 CI: 1.170, 9.940; P=0.025), menstrual status (HR=3.692, 95 CI: 1.021, 13.344, P=0.046), and chemotherapy (HR=0.238, 95 CI: 0.079, 0.720; P=0.011) were independent factors affecting DFS. After PSM, the 5-year DFS rate of the treatment group was 89.2%, while that of the control group was 83.5%(P=0.237). The 5-year OS rate of the treatment group was 96.1%, while that of the control group was 84.7%(P=0.036). Conclusion: Postoperative targeted therapy with trastuzumab can reduce the risk of recurrence and metastasis in patients with HER-2-positive T1N0M0 stage breast cancer.

Research Progress of Fibroblast Growth Factor Receptor Signaling Pathway in Breast Cancer / 中国医学科学院学报

Breast cancer,one of the common malignant tumors in women,has shown rising incidence in recent years,posing a serious threat to women's health.The advancement of molecular biology facilitates the revealing of the relationships between signaling pathways and breast cancer.Fibroblast growth factor receptor (FGFR) signaling pathway plays an important role in the proliferation,survival,differentiation,migration,and apoptosis of breast cancer cells.Strategies targeting the FGFR signaling pathway thus exhibit a promising prospect in breast cancer treatment.

Multicenter study of the clinicopathological features and recurrence risk prediction model of early-stage breast cancer with low-positive human epidermal growth factor receptor 2 expression in China (Chinese Society of Breast Surgery 021) / 中华医学杂志(英文版)

BACKGROUND@#: Breast cancer with low-positive human epidermal growth factor receptor 2 (HER2) expression has triggered further refinement of evaluation criteria for HER2 expression. We studied the clinicopathological features of early-stage breast cancer with low-positive HER2 expression in China and analyzed prognostic factors.@*METHODS@#: Clinical and pathological data and prognostic information of patients with early-stage breast cancer with low-positive HER2 expression treated by the member units of the Chinese Society of Breast Surgery and Chinese Society of Surgery of Chinese Medical Association, from January 2015 to December 2016 were collected. The prognostic factors of these patients were analyzed.@*RESULTS@#: Twenty-nine hospitals provided valid cases. From 2015 to 2016, a total of 25,096 cases of early-stage breast cancer were treated, 7642 (30.5%) of which had low-positive HER2 expression and were included in the study. After ineligible cases were excluded, 6486 patients were included in the study. The median follow-up time was 57 months (4-76 months). The disease-free survival rate was 92.1% at 5 years, and the overall survival rate was 97.4% at 5 years. At the follow-up, 506 (7.8%) cases of metastasis and 167 (2.6%) deaths were noted. Multivariate Cox regression analysis showed that tumor stage, lymphvascular invasion, and the Ki67 index were related to recurrence and metastasis (P < 0.05). The recurrence risk prediction model was established using a machine learning model and showed that the area under the receiving operator characteristic curve was 0.815 (95% confidence interval: 0.750-0.880).@*CONCLUSIONS@#: Early-stage breast cancer patients with low-positive HER2 expression account for 30.5% of all patients. Tumor stage, lymphvascular invasion, and the Ki67 index are factors affecting prognosis. The recurrence prediction model for breast cancer with low-positive HER2 expression based on a machine learning model had a good clinical reference value for predicting the recurrence risk at 5 years.@*TRIAL REGISTRATION@#: ChiCTR.org.cn, ChiCTR2100046766.

Expert consensus on the clinical application of PI3K/AKT/mTOR inhibitors in the treatment of advanced breast cancer / 中华肿瘤杂志

Phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway (PAM pathway) plays an important role in the development of breast cancer and are closely associated with the resistance to endocrine therapy in advanced breast cancer. Therefore, anti-cancer treatment targeting key molecules in this signaling pathway has become research hot-spot in recent years. Randomized clinical trials have demonstrated that PI3K/AKT/mTOR inhibitors bring significant clinical benefit to patients with advanced breast cancer, especially to those with hormone receptor (HR)-positive, human epidermal growth factor receptor (HER) 2-negative advanced breast cancer. Alpelisib, a PI3K inhibitor, and everolimus, an mTOR inhibitor, have been approved by Food and Drug Administration. Based on their high efficacy and relatively good safety profile, expanded indication of everolimus in breast cancer have been approved by National Medical Products Administration. Alpelisib is expected to be approved in China in the near future. The members of the consensus expert panel reached this consensus to comprehensively define the role of PI3K/AKT/mTOR signaling pathway in breast cancer, efficacy and clinical applications of PI3K/AKT/mTOR inhibitors, management of adverse reactions, and PIK3CA mutation detection, in order to promote the understanding of PI3K/AKT/mTOR inhibitors for Chinese oncologists, improve clinical decision-making, and prolong the survival of target patient population.

Expresión tumoral de BRCA1 y resultados clínicos en pacientes uruguayas diagnosticadas de cáncer de mama antes de los 40 años / BRCA1 tumor expression and clinical results in uruguayan patients diagnosed with breast cancer before the age of 40 years old / Expressão tumoral de BRCA1 e resultados clínicos em pacientes uruguaias com diagnóstico de câncer de mama antes dos 40 anos

Resumen: Las mutaciones de BRCA1 son raras en el cáncer de mama (CM) esporádico; sin embargo, su expresión a nivel tumoral se encuentra disminuida o ausente en 30%-50% de los casos. Objetivo: valorar la expresión tumoral de BRCA1 por inmunohistoquímica (IHQ) en mujeres uruguayas diagnosticadas de CM antes de los 40 años. Material y método: se incluyeron pacientes diagnosticadas de CM antes de los 40 años. Se utilizaron los anticuerpos monoclonales anti-BRCA1 MS110 contra el extremo N-terminal y GLK-2 contra el extremo C-terminal. Se calculó la sobrevida global (SVG) y la sobrevida libre de enfermedad (SVLE), para la construcción de las curvas se utilizó el método de Kaplan-Meier y la diferencia de sobrevida se evaluó mediante el test de log rank. Resultados: se incluyeron 40 pacientes, la SVG y la SVLE a cinco años fueron de 73% y 60% respectivamente. La expresión de BRCA1 mediante GLK-2 fue <10% en 16 de las 40 pacientes (40%). La SVG y la SVLE a cinco años para las pacientes con expresión <10% fue de 56% vs 85% para las pacientes con expresión >10% (p=0,015) y de 40% vs 72% (p=0,034) respectivamente. La expresión de BRCA1 mediante MS110 fue <10% en 11 de las 40 pacientes (27,5%). No se encontraron diferencias en la SVG ni en la SVLE a cinco años con este marcador. Conclusión: la pérdida de la expresión tumoral de BRCA1 determinada mediante GLK-2 se encontró en el 40% de las pacientes incluidas y se asoció a una menor SVG y SVLE, por lo que podría tener un valor pronóstico desfavorable en estas pacientes.

Summary: BRCA1 mutations are rare in sporadic breast cancer (CM), however their expression at the tumor level is diminished or absent in 30-50% of cases. Objective: to assess the tumor expression of BRCA1 using immunohistochemistry (IHC) in Uruguayan women diagnosed with BC before the age of 40 years. Material and methods: patients diagnosed with BC before the age of 40 between. The antibodies used were anti BRCA1 MS110 monoclonal antibodies against the N-terminal end and GLK-2 against the C-terminal. Overall survival (OS) and disease free survival (DFS) were calculated; the curves were developed using the Kaplan-Meier method and the difference in survival was evaluated through the log rank test. Results: the average age of the 40 patients included was 36 years. The 5-year OS and DFS were 73% and 60% respectively. The expression of BRCA1 with GLK-2 was <10% in 16 of the 40 patients included (40%). The 5-year OS and DFS for patients with <10% expression was 56% vs. 85% for patients with >10% (p=0.015) and 40% vs. 72% (p = 0.034) respectively. The expression of BRCA1 by MS110 was <10% in 11 of the 40 patients included (27.5%). No differences were found in the 5-year OS or DFS based on the expression of this marker. Conclusion: The loss of BRCA1 expression using GLK-2, which suggests the presence of a truncated protein, was associated with a statistically significantly lower OS and DFS, that the decrease in the BRCA1 protein as determined by GLK2 has an unfavorable prognostic value for young patients with BC.

Resumo: As mutações de BRCA1 são raras no câncer de mama (CM) esporádico; no entanto sua expressão no nível tumoral está diminuída ou ausente em 30-50% dos casos. Objetivo: avaliar a expressão tumoral de BRCA1 por imuno-histoquímica (IHQ) em mulheres uruguaias com diagnóstico de CM antes dos 40 anos. Material e métodos: foram incluídas pacientes com diagnóstico de CM antes dos 40 anos. Foram utilizados anticorpos monoclonais anti BRCA1 MS110 contra o extremo N-terminal e GLK-2 contra o extremo C-terminal. A sobrevida global (SVG) e a sobrevida livre de enfermidade (SVLE) foram calculadas; o método de Kaplan-Meier foi utilizado para a construção das curvas e a diferença de sobrevida foi avaliada usando o teste de log-rank. Resultados: foram incluídas 40 pacientes; a SVG e a SVLE aos 5 anos foram 73% e 60% respectivamente. A expressão de BRCA1 mediante GLK-2 foi <10% em 16 das 40 pacientes (40 %). A SVG e a SVLE aos 5 anos para as pacientes com expressão £10% foi 56% vs. 85% para as pacientes com expressão >10% (p=0,015) e 40% vs. 72% (p=0,034) respectivamente. A expressão de BRCA1 mediante MS110 foi =10% em 11 das 40 pacientes (27,5%). Não foram encontradas diferenças na SVG nem na SVLE aos 5 anos com este marcador. Conclusão: foi encontrada perda da expressão tumoral de BRCA1 determinada por GLK-2 em 40% das pacientes incluídas e foi associada a uma menor SVG e SVLE, o que poderia ter um valor prognóstico desfavorável nestas pacientes.

Linc-OIP5 in the breast cancer cells regulates angiogenesis of human umbilical vein endothelial cells through YAP1/Notch/NRP1 signaling circuit at a tumor microenvironment

BACKGROUND: LincRNAs have been revealed to be tightly associated with various tumorigeneses and cancer development, but the roles of specific lincRNA on tumor-related angiogenesis was hardly studied. Here, we aimed to investigate whether linc-OIP5 in breast cancer cells affects the angiogenesis of HUVECs and whether the linc-OIP5 regulations are involved in angiogenesis-related Notch and Hippo signaling pathways. METHODS: A trans-well system co-cultured HUVECs with linc-OIP5 knockdown breast cancer cell MDA-MB-231 was utilized to study the proliferation, migration and tube formation abilities of HUVECs and alterations of related signaling indicators in breast cancer cells and their conditioned medium through a series of cell and molecular experiments. RESULTS: Overexpressed linc-OIP5, YAP1, and JAG1 were found in breast cancer cell lines MCF7 and MDA-MB-231 and the expression levels of YAP1 and JAG1 were proportional to the breast cancer tissue grades. MDA-MB-231 cells with linc-OIP5 knockdown led to weakened proliferation, migration, and tube formation capacity of co-cultured HUVECs. Besides, linc-OIP5 knockdown in co-cultured MDA-MB-231 cells showed downregulated YAP1 and JAG1 expression, combined with a reduced JAG1 level in conditioned medium. Furthermore, a disrupted DLL4/Notch/NRP1 signaling in co-cultured HUVECs were also discovered under this condition. CONCLUSION: Hence, linc-OIP5 in MDA-MB-231 breast cancer cells may act on the upstream of the YAP1/Notch/NRP1 signaling circuit to affect proliferation, migration, and tube formation of co-cultured HUVECs in a non-cellular direct contact way through JAG1 in conditioned medium. These findings at least partially provide a new angiogenic signaling circuit in breast cancers and suggest linc-OIP5 could be considered as a therapeutic target in angiogenesis of breast cancers.

miR-185-5p response to usnic acid suppresses proliferation and regulating apoptosis in breast cancer cell by targeting Bcl2

BACKGROUND: Breast cancer is the most common cancer types among women. Recent researches have focused on determining the efficiency of alternative molecules and miRNAs in breast cancer treatment. The AIMof this study was to determine the effect of usnic acid response-miR-185-5p on proliferation in the breast cancer cell and to determine its relationship with apoptosis pathway. METHODS: The cell proliferation and cell apoptosis rate were significantly increased following the ectopic expression of miR-185-5p in BT-474 cells. Furthermore, the results of cell cycle assay performed by flow cytometry revealed that the transfection with miR-185-5p induced G1/S phase arrest. The apoptosis-related genes expression analysis was performed by qRT-PCR and the direct target of miR-185-5p in BT-474 cells was identified by western blot and luciferase reporter assay. RESULTS: Our data showed that miR-185-5p can cause significant changes in apoptosis-related genes expression levels, suggesting that cell proliferation was suppressed by miR-185-5p via inducing apoptosis in breast cancer cells. According to western blot results, miR-185-5p lead to decrease BCL2 protein level in BT-474 cells and direct target of miR-185-5p was identified as BCL by luciferase reporter assay. CONCLUSION: This study revealed that miR-185-5p may be an effective agent in the treatment of breast cancer.

Enhanced production of glutaminase-free L-asparaginase by marine Bacillus velezensis and cytotoxic activity against breast cancer cell lines

Background: The increasing rate of breast cancer globally requires extraordinary efforts to discover new effective sources of chemotherapy with fewer side effects. Glutaminase-free L-asparaginase is a vital chemotherapeutic agent for various tumor malignancies. Microorganisms from extreme sources, such as marine bacteria, might have high L-asparaginase productivity and efficiency with exceptional antitumor action toward breast cancer cell lines. Results: L-Asparaginase-producing bacteria, Bacillus velezensis isolated from marine sediments, were identified by 16S rRNA sequencing. L-Asparaginase production by immobilized cells was 61.04% higher than that by free cells fermentation. The significant productivity of enzyme occurred at 72 h, pH 6.5, 37°C, 100 rpm. Optimum carbon and nitrogen sources for enzyme production were glucose and NH4Cl, respectively. L-Asparaginase was free from glutaminase activity, which was crucial medically in terms of their severe side effects. The molecular weight of the purified enzyme is 39.7 KDa by SDS-PAGE analysis and was ideally active at pH 7.5 and 37°C. Notwithstanding, the highest stability of the enzyme was found at pH 8.5 and 70°C for 1 h. The enzyme kinetic parameters displayed Vmax at 41.49 µmol/mL/min and a Km of 3.6 × 10−5 M, which serve as a proof of the affinity to its substrate. The anticancer activity of the enzyme against breast adenocarcinoma cell lines demonstrated significant activity toward MDA-MB-231 cells when compared with MCF-7 cells with IC50 values of 12.6 ± 1.2 µg/mL and 17.3 ± 2.8 µg/mL, respectively. Conclusion: This study provides the first potential of glutaminase-free L-asparaginase production from the marine bacterium Bacillus velezensis as a prospect anticancer pharmaceutical agent for two different breast cancer cell lines.

Triiodothyronine (T3) upregulates the expression of proto-oncogene TGFA independent of MAPK/ERK pathway activation in the human breast adenocarcinoma cell line, MCF7

ABSTRACT Objective: To verify the physiological action of triiodothyronine T3 on the expression of transforming growth factor α (TGFA) mRNA in MCF7 cells by inhibition of RNA Polymerase II and the MAPK/ERK pathway Materials and methods: The cell line was treated with T3 at a physiological dose (10−9M) for 10 minutes, 1 and 4 hour (h) in the presence or absence of the inhibitors, α-amanitin (RNA polymerase II inhibitor) and PD98059 (MAPK/ERK pathway inhibitor). TGFA mRNA expression was analyzed by RT-PCR. For data analysis, we used ANOVA, complemented with the Tukey test and Student t-test, with a minimum significance of 5%. Results: T3 increases the expression of TGFA mRNA in MCF7 cells in 4 h of treatment. Inhibition of RNA polymerase II modulates the effect of T3 treatment on the expression of TGFA in MCF7 cells. Activation of the MAPK/ERK pathway is not required for T3 to affect the expression of TGFA mRNA. Conclusion: Treatment with a physiological concentration of T3 after RNA polymerase II inhibition altered the expression of TGFA. Inhibition of the MAPK/ERK pathway after T3 treatment does not interfere with the TGFA gene expression in a breast adenocarcinoma cell line.

Upregulation of miR-129-5p increases the sensitivity to Taxol through inhibiting HMGB1-mediated cell autophagy in breast cancer MCF-7 cells

Although Taxol has improved the survival of cancer patients as a first-line chemotherapeutic agent, an increasing number of patients develop resistance to Taxol after prolonged treatment. The potential mechanisms of cancer cell resistance to Taxol are not completely clear. It has been reported that microRNAs (miRNAs) are involved in regulating the sensitivity of cancer cells to various chemotherapeutic agents. In this study, we aimed to explore the role of miR-129-5p in regulating the sensitivity of breast cancer cells to Taxol. Cell apoptosis and autophagy, and the sensitivity of MCF-7 cells to Taxol were assessed with a series of in vitro assays. Our results showed that the inhibition of autophagy increased the Taxol-induced apoptosis and the sensitivity of MCF-7 cells to Taxol. Up-regulation of miR-129-5p also inhibited autophagy and induced apoptosis. Furthermore, miR-129-5p overexpression increased the sensitivity of MCF-7 cells to Taxol. High mobility group box 1 (HMGB1), a target gene of miR-129-5p and a regulator of autophagy, was negatively regulated by miR-129-5p. We found that interference of HMGB1 enhanced the chemosensitivity of Taxol by inhibiting autophagy and inducing apoptosis in MCF-7 cells. Taken together, our findings suggested that miR-129-5p increased the chemosensitivity of MCF-7 cells to Taxol through suppressing autophagy and enhancing apoptosis by inhibiting HMGB1. Using miR-129-5p/HMGB1/autophagy-based therapeutic strategies may be a potential treatment for overcoming Taxol resistance in breast cancer.

Effects of glutamine deprivation on oxidative stress and cell survival in breast cell lines

BACKGROUND: Tumourigenic cells modify metabolic pathways In order to facilitate increased proliferation and cell survival resulting in glucose-and glutamine addiction. Previous research indicated that glutamine deprivation resulted in potential differential activity targeting tumourigenic cells more prominently. This is ascribed to tumourigenic cells utilising increased glutamine quantities for enhanced glycolysis-and glutaminolysis. In this study, the effects exerted by glutamine deprivation on reactive oxygen species (ROS) production, mitochondrial membrane potential, cell proliferation and cell death in breast tumourigenic cell lines (MCF-7, MDA-MB-231, BT-20) and a non-tumourigenic breast cell line (MCF-10A) were investigated. RESULTS: Spectrophotometry demonstrated that glutamine deprivation resulted in decreased cell growth in a time-dependent manner. MCF-7 cell growth was decreased to 61% after 96 h of glutamine deprivation; MDA-MB-231 cell growth was decreased to 78% cell growth after 96 h of glutamine deprivation, MCF-10A cell growth was decreased 89% after 96 h of glutamine deprivation and BT-20 cell growth decreased to 86% after 24 h of glutamine deprivation and remained unchanged until 96 h of glutamine deprivation. Glutamine deprivation resulted in oxidative stress where superoxide levels were significantly elevated after 96 h in the MCF-7-and MDA-MB-231 cell lines. Time-dependent production of hydrogen peroxide was accompanied by aberrant mitochondrial membrane potential. The effects of ROS and mitochondrial membrane potential were more prominently observed in the MCF-7 cell line when compared to the MDA-MB-231-, MCF-10A- and BT-20 cell lines. Cell cycle progression revealed that glutamine deprivation resulted in a significant increase in the S-phase after 72 h of glutamine deprivation in the MCF-7 cell line. Apoptosis induction resulted in a decrease in viable cells in all cell lines following glutamine deprivation. In the MCF-7 cells, 87.61% of viable cells were present after 24 h of glutamine deprivation. CONCLUSION: This study demonstrates that glutamine deprivation resulted in decreased cell proliferation, time-dependent- and cell line-dependent ROS generation, aberrant mitochondrial membrane potential and disrupted cell cycle progression. In addition, the estrogen receptor positive MCF-7 cell line was more prominently affected. This study contributes to knowledge regarding the sensitivity of breast cancer cells and non-tumorigenic cells to glutamine deprivation.

WT1 expression as a potential biomarker of malignancy in canine breast tumor / La expresión de WT1 como un biomarcador potencial maligno en un tumor de mama canino

SUMMARY: Veterinary oncology is very important nowadays to get a better understanding of human carcinogenesis. Estrogen receptor, progesterone receptor and Human Epidermal Growth Factor receptor 2 are frequently evaluated by immunohistochemistry (HIC) in human breast tumor. WT1 is an oncogene, its overexpression has been detected in leukemia and diverse solid tumors like breast cancer, lung cancer and mesothelioma in humans. WT1 expression was evaluated in 15 canine breast tumors (CBT) diagnosed by histopathological analysis to find its relationship with neoplasia and malignancy. IHC and RT-PCR were performed in CBT tissues. Fisher´s test was used to analyze WT1 relationship with malignancy. Of the 15 tumors, 9 (60 %) were diagnosed as benign and 6 (40 %) were malignant. With IHC, WT1 expression was positive only in biopsies diagnosed as malignant. Expression of WT1 by RT-PCR was detected in 14 of the 15 tumors (93.33 %) as well as in control healthy mammary gland. Clinical significance: This study describes for the first time a close correlation between CBT and a positive result for WT1 expression with IHC; hence, it can be used as a biomarker for this neoplasia and as an indicator of malignancy. RT-PCR analysis also showed to be good option to detect WT1 expression. These results will be useful to further investigations to elucidate WT1-related signaling pathways in CBT. Also to know molecules that regulate the translation of this protein as a marker for tumor progression.

RESUMEN: La oncología veterinaria es muy importante hoy en día para comprender mejor la carcinogénesis humana. El receptor de estrógeno, el receptor de progesterona y el receptor 2 del factor de crecimiento epidérmico humano se evalúan con frecuencia mediante inmunohistoquímica (HIC) en tumores de mama humanos. WT1 es un oncogén, su sobreexpresión se ha detectado en leucemia y en diversos tumores sólidos como el cáncer de mama, cáncer de pulmón y mesotelioma en humanos. La expresión de WT1 se evaluó en 15 tumores de mama caninos (TCC) diagnosticados mediante análisis histopatológico para encontrar su relación con la neoplasia y la malignidad. IHC y RT-PCR se realizaron en tejidos CBT. La prueba de Fisher se utilizó para analizar la relación de WT1 con la malignidad. De los 15 tumores, 9 (60 %) fueron diagnosticados como benignos y 6 (40 %) fueron malignos. Con IHC, la expresión de WT1 fue positiva solo en biopsias diagnosticadas como malignas. La expresión de WT1 por RT-PCR se detectó en 14 de los 15 tumores (93,33 %), así como en el control de la glándula mamaria sana. Importancia clínica: este estudio describe por primera vez una estrecha correlación entre la TCC y un resultado positivo para la expresión de WT1 con IHC; por lo tanto, se puede utilizar como un biomarcador para esta neoplasia y como un indicador de malignidad. El análisis por RT-PCR también demostró ser una buena opción para detectar la expresión de WT1. Estos resultados serán útiles para futuras investigaciones para dilucidar las vías de señalización relacionadas con WT1 en la TCC. También para conocer moléculas que regulan la traducción de esta proteína como marcador de progresión tumoral.

Identification of a subtype of poorly differentiated invasive ductal carcinoma of the breast based on vimentin and e-cadherin expression / Identificação de um subtipo pouco diferenciado de carcinoma ductal invasivo de mama, baseado na expressão da vimentina e E-caderina

Abstract Objective The use of molecular markers can identify a subgroup of tumors with distinct recurrence patterns. The present study aimed to characterize the immunohistochemical expression of vimentin (VIM), of E-cadherin (CDH1), and of cytokeratin 5 (CK5) in patients with invasive ductal carcinomas (IDCs). Methods We have constructed a tissuemicroarray (TMA) from87 patients with IDC of the breast. Immunohistochemistry (IHC) was performed to study the expression of estrogen and progesterone receptors (ER and PgR), human epidermal growth factor receptor 2 (HER2), VIM, CDH1, CK5, and Ki67. The tumors were classified as luminal A and B (n = 39), HER2 enriched (n = 25), and triple-negative (TNBC) (n = 23), based on the IHC expression. Results We have observed that luminal A and B tumors lack the VIM+/CDH1-/low phenotype. This phenotype was observed in 16.5% of the HER2+ tumors and in 60% of the TNBC tumors (p = 0.0001). Out of a total of 20 TNBC tumors, the CK5 (basal-like marker) was positive in 11 of them. The VIM+/CDH1-/low phenotype was observed in 5 CK5+ TNBC tumors (45%) and in 7 out of 9 CK5- TNBC tumors (78%) (p = 0.02). The median Ki67 index in the VIM+/CDH1-/low tumors was 13.6 (range: 17.8-45.4) compared with 9.8 (range: 4.1-38.1) in other tumors (p = 0.0007). The presence of lymph nodemetastasis was less frequent in patients with VIM+/CDH1-/low tumors (23% versus 61%; X2 test; p = 0.01). Conclusion Our findings suggest that the expression of VIM and CDH1 can identify a subset of IDCs of the breast with a mesenchymal phenotype associated with poor prognosis, high-grade lesion, and high mitotic index.

Resumo Objetivo O uso de marcadores moleculares pode identificar subtipos tumorais com diferentes taxas de recidiva. O objetivo do presente estudo é caracterizar a expressão imunohistoquímica da vimentina (VIM), da E-caderina (CDH1) e de CK5 em pacientes com carcinoma ductal invasivo (CDI) da mama. Métodos Utilizamos uma matriz de amostras teciduais (TMA, na sigla em inglês) de 87 pacientes com CDI da mama. Para avaliar a expressão dos receptores de estrogênio (RE) e receptores de progesterona (RP), HER2, VIM, CDH1, CK5 e Ki67, utilizamos imunohistoquímica. Os tumores foram classificados como luminal A e B (n = 39), HER2+ (n = 25) e triplo negativo (TNBC) (n = 23). Resultados Foi observado que tumores luminais A e B não expressaram o fenótipo VIM+/CDH1-/low. Este fenótipo foi observado em 16,5% dos tumores HER2+ e em 60% dos tumores TNBC (p = 0,0001). Dos 20 tumores TNBC, a CK5 (marcador de tumor basalóide) foi super expressa em 11 amostras. O fenótipo VIM+/CDH1-/low foi observado em 5 tumores CK5+ TNBC (45%) e em 7 dos 9 tumores CK5- TNBC (78%) (p = 0,02). A expressão média de Ki67 nos tumores VIM+/CDH1-/low foi 13.6 (amplitude de 17,8 a 45,4) comparado com 9,8 (amplitude de 4,1 a 38,1) nos outros tumores (p = 0,0007). A presença demetástase linfonodal foimenor em tumores com fenótipo VIM+/CDH1-/low (23% contra 61%; teste X2; p = 0,01). Conclusão Nossos achados sugerem que a expressão de VIM e CDH1 pode identificar um subtipo de CDI da mama com fenótipo mesenquimal associado a pior prognóstico, lesões de alto grau e alto índice mitótico.

Exercício físico aeróbico de intensidade moderada reduz a velocidade de crescimento e modula o metabolismo energético tumoral em modelo experimental de câncer de mama triplo-negativo / Moderate-intensity aerobic physical exercise reduces tumor growth velocity and modulates tumor energy metabolism in the experimental model of triple-negative breast cancer

O câncer de mama ocupa o primeiro lugar em mortalidade dentre todos os tipos de câncer. O subtipo triplo-negativo (triple-negative breast cancer - TNBC) representa 15-20% de todos os tipos de câncer de mama com alta prevalência em mulheres pré-menopausa e destaca-se pelo seu grande tamanho tumoral e agressividade no estabelecimento de metástases, com impacto direto na redução da sobrevida dos pacientes. Apesar das evidências sobre os efeitos anti-tumorigênicos do exercício físico, tanto na prevenção como durante a carcinogênese, é comum que pacientes alterem sua rotina após o diagnóstico de câncer, frequentemente reduzindo as atividades físicas durante e após o tratamento. Em adição, os mecanismos pelos quais o exercício físico exerce papel anti-tumoral são pouco compreendidos. O objetivo deste estudo foi avaliar os efeitos do exercício físico aeróbico moderado em modelo experimental de câncer de mama de tipo triplo-negativo, com ênfase na modulação do metabolismo energético tumoral. Foram utilizados camundongos fêmeas BALB/c em desenho experimental de 12 semanas, cuja inoculação de 1x104 células 4T1 foi realizada após 8 semanas de treinamento. Após protocolo de exercício aeróbico moderado em esteira, foram realizadas análises do metabolismo mitocondrial tumoral, composição lipídica e expressão de genes relacionados à bioenergética e proliferação celular. Os resultados mostraram que o exercício aeróbico moderado reduziu 54,5% do volume e 42% da massa tumoral de animais que foram treinados antes e após a inoculação tumoral. Animais treinados apresentaram fosforilação oxidativa mais próxima ao seu limite máximo respiratório e menor respiração mitocondrial no tecido tumoral quando comparados ao grupo sedentário. O treinamento ocasionou redução no conteúdo de ácido fosfatídico e fosfatidilcolina. Enquanto a análise de expressão relativa de mRNA demonstrou aumento na expressão de genes relacionados à via metabólica glicolítica, como Hif1a, Glut-1, HKII, Ldha e Pdk, além dos supressores tumorais p53 e Lats2. Nossos resultados sugerem que a redução na velocidade de crescimento tumoral proporcionada pelo exercício físico aeróbico de carga moderada seja devida, pelo menos em parte, à modulação do metabolismo energético tumoral. Em conjunto, os dados do nosso estudo abrem novas perspectivas para a identificação de vias metabólicas sensíveis ao exercício físico, permitindo o melhor o entendimento de seus efeitos antitumorigênicos

Breast cancer ranks first in mortality among all types of cancer. The triple-negative breast cancer (TNBC) accounts for 15-20% of all types of breast cancer with a high prevalence in premenopausal women and is notable for its large tumor size and aggressiveness in the establishment of metastasis, with a direct impact on the reduction of patients' survival. Altough evidence highlight the anti-tumorigenic effects of physical exercise both on the prevention as well as during carcinogenesis, patients commonly change their routine after cancer diagnostic, usually reducing physical activity during and after treatment. Moreover, the mechanisms underlying the anti-tumor role of physical exercise remain poorly understood. The objective of this study was to evaluate the effects of moderate aerobic physical exercise in an experimental model of triple-negative breast cancer, with emphasis on the modulation of tumor energy metabolism. Female BALB / c mice were used in a 12-week experimental design, whose inoculation of 1x104 4T1 cells was performed after 8 weeks of training. After the protocol of moderate aerobic exercise was carried out on the treadmill, analyzes of mitochondrial tumor metabolism, lipid content and qPCR of genes related to bioenergetics and tumorigenic process were performed. The results showed that moderate aerobic exercise reduced 54.5% of the volume and 42% the tumor mass of animals trained before and after tumor inoculation. Trained animals showed oxidative phosphorylation closest to the maximum respiratory limit and lower mitochondrial respiration in tumor tissue when compared to the sedentary group. The training resulted in a reduction in the content of phosphatidic acid and phosphatidylcholine. In the trained group, relative mRNA quantification analysis showed increased expression of genes related to the glycolytic metabolic pathway, such as Hif1a, Glut-1, HKII, Ldha, and Pdk, as well as of the tumor suppressors p53 and Lats2. Our results suggest that the reduction in tumor growth velocity provided by moderate-intensity aerobic physical exercise is due, at least in part, to the modulation of tumor energy metabolism. Together, data from our study open new perspectives for the identification of metabolic pathways sensitive to exercise, allowing better understanding of its anti-tumorigenic effects

Estrogen and progesterone promote breast cancer cell proliferation by inducing cyclin G1 expression

Breast cancer is the most common cause of cancer among women in most countries (WHO). Ovarian hormone disorder is thought to be associated with breast tumorigenesis. The present study investigated the effects of estrogen and progesterone administration on cell proliferation and underlying mechanisms in breast cancer MCF-7 cells. It was found that a single administration of estradiol (E2) or progesterone increased MCF-7 cell viability in a dose-dependent manner and promoted cell cycle progression by increasing the percentage of cells in the G2/M phase. A combination of E2 and progesterone led to a stronger effect than single treatment. Moreover, cyclin G1 was up-regulated by E2 and/or progesterone in MCF-7 cells. After knockdown of cyclin G1 in MCF-7 cells using a specific shRNA, estradiol- and progesterone-mediated cell viability and clonogenic ability were significantly limited. Additionally, estradiol- and progesterone-promoted cell accumulation in the G2/M phase was reversed after knockdown of cyclin G1. These data indicated that estrogen and progesterone promoted breast cancer cell proliferation by inducing the expression of cyclin G1. Our data indicated that novel therapeutics against cyclin G1 are promising for the treatment of estrogen- and progesterone-mediated breast cancer progression.

Evaluation of survivin immunoexpression in the differentiation of high- and low-grade breast ductal carcinoma in situ / Expressão da proteína survivina em carcinoma ductal in situ de mama de alto e de baixo grau

ABSTRACT Objective To evaluate the expression of survivin protein in low- and high-grade ductal carcinoma in situ. Methods Breast tissue fragments obtained by incisional biopsy and surgical procedures of 37 women with ductal carcinoma in situ of the breast were subdivided into two groups: Group A, composed of women with low-grade ductal carcinoma in situ, and Group B, women with high-grade ductal carcinoma in situ. Survivin protein expression test was performed by immunohistochemistry, using a monoclonal antibody clone I2C4. The criterion to evaluate survivin immunoexpression was based on the percentage of neoplastic cells that presented brown-gold staining. This criterion was positive when the percentage of stained cells was ≥10%. Results The survivin protein was expressed in 22 out of 24 cases of high-grade ductal carcinoma in situ (78%), whereas, in Group A, of low-grade ductal carcinoma in situ (n=13), it was positive in only 6 cases (21.40%; p=0.004). Conclusion The frequency of expression of survivin was significantly higher in the group of patients with high-grade ductal carcinoma in situ compared to those in the low-grade ductal carcinoma in situ group.

RESUMO Objetivo Avaliar a imunoexpressão da proteína survivina nos carcinomas ductais in situ de mama de baixo e de alto graus. Métodos Fragmentos de tecido mamários obtidos por biópsia incisional e procedimentos cirúrgicos de 37 mulheres acometidas por carcinoma ductal in situ de mama foram subdivididos em dois grupos: Grupo A, formado por mulheres com carcinoma ductal in situ de baixo grau; e Grupo B, por mulheres com carcinoma ductal in situ de alto grau. A pesquisa de expressão da proteína survivina foi realizada pela técnica de imuno-histoquímica, utilizando-se anticorpo monoclonal clone I2C4. O critério de avaliação da imunoexpressão da survivina baseou-se na percentagem de células neoplásicas que apresentava coloração castanho-dourada. Considerouse tal critério positivo quando a percentagem de células apresentasse marcação ≥10%. Resultados A proteína survivina apresentou-se expressa em 22 dos 24 casos de carcinoma ductal in situ de alto grau (78%), enquanto no Grupo A, de carcinoma ductal in situ de baixo grau (n=13), apresentou-se positiva em apenas 6 casos (21,40%; p=0,004). Conclusão O índice de frequência de expressão da survivina foi significativamente mais elevado no grupo de pacientes com carcinoma ductal in situ de alto grau, quando comparado às do grupo com carcinoma ductal in situ de baixo grau.

ADAR1-mediated RNA-editing of 3'UTRs in breast cancer

BACKGROUND: Whole transcriptome RNA variant analyses have shown that adenosine deaminases acting on RNA ( ADAR ) enzymes modify a large proportion of cellular RNAs, contributing to transcriptome diversity and cancer evolution. Despite the advances in the understanding of ADAR function in breast cancer, ADAR RNA editing functional consequences are not fully addressed. RESULTS: We characterized A to G(I) mRNA editing in 81 breast cell lines, showing increased editing at 3'UTR and exonic regions in breast cancer cells compared to immortalized non-malignant cell lines. In addition, tumors from the BRCA TCGA cohort show a 24% increase in editing over normal breast samples when looking at 571 well-characterized UTRs targeted by ADAR1. Basal-like subtype breast cancer patients with high level of ADAR1 mRNA expression shows a worse clinical outcome and increased editing in their 3'UTRs. Interestingly, editing was particularly increased in the 3'UTRs of ATM, GINS4 and POLH transcripts in tumors, which correlated with their mRNA expression. We confirmed the role of ADAR1 in this regulation using a shRNA in a breast cancer cell line (ZR-75-1). CONCLUSIONS: Altogether, these results revealed a significant association between the mRNA editing in genes related to cancer-relevant pathways and clinical outcomes, suggesting an important role of ADAR1 expression and function in breast cancer.