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1.
Clin Transl Oncol ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090421

RESUMO

BACKGROUND: Primary carcinoma of the ovary (OCs) are responsible for a significant number of deaths related to cancer, and have the highest rate of death related to cancers of the female reproductive organs. Programmed cell death 1 (PD1) protein, acts as an immune checkpoint, and has an important role in the down-regulation of the immune system by preventing the activation of T-cells, which will weaken the autoimmunity and increases self-tolerance. This study aimed at the evaluation of the immunohistochemical (IHC) expression of PD-L1 in various primary surface ovarian epithelial tumours and to test its correlation with different clinicopathological parameters together with the expression of a panel of P53, ER and PR. METHODS: A set of 102 cases of primary ovarian surface epithelial neoplasms (benign, borderline and malignant) were collected to construct Tissue Microarray (TMA) using 3 tissue cores from each case. IHC for PD-L1, p53, PR and ER was performed. The expression of PD-L1 was evaluated in relation to some clinicopathological parameters and to the expression patterns of other markers. RESULTS: Expression of PD-L1 was detected in about 51% (n = 36) of malignant tumours. The malignant group significantly showed PD-L1 positivity compared to borderline and benign groups. The malignant tumours significantly showed PD-L1 and total p53 positivity in comparison to borderline group. Also, malignant tumours significantly showed higher combined positivity of PD-L1 and either PR or ER compared to borderline and benign lesions. No significant correlation was appreciated between PD-L1 expression and with any of the studied clinicopathological parameters. CONCLUSIONS: This study showed a significant PD-L1 expression in malignant primary surface epithelial tumours. Construction of a panel of IHC markers, including PD-L1, could have a potential value to define patients those would benefit from the addition of immunotherapy to the treatment plan.

2.
Eur Radiol ; 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075300

RESUMO

OBJECTIVES: Li-Fraumeni syndrome (LFS) is a cancer syndrome associated with early-onset neoplasias. The use of whole-body magnetic resonance imaging (WBMRI) is recommended for regular cancer screening, however, evidence supporting the benefits in asymptomatic LFS patients is limited. This study aims to assess the clinical utility of WBMRI in germline TP53 mutation carriers at baseline and follow-up. MATERIALS AND METHODS: We systematically searched PubMed, Cochrane, and Embase databases for studies evaluating WBMRI as an early detection method for tumor screening in patients with LFS. We pooled the prevalence of the included variables along with their corresponding 95% confidence intervals (CIs). Statistical analyses were performed using R software, version 4.3.1. RESULTS: From 1687 results, 11 comprising 703 patients (359 females (51%); with a median age of 32 years (IQR 1-74)) were included. An estimated detection rate of 31% (95% CI: 0.28, 0.34) for any suspicious lesions was found in asymptomatic TP53 carriers who underwent baseline WBMRI. A total of 277 lesions requiring clinical follow-up were identified in 215 patients. Cancer was confirmed in 46 lesions across 39 individuals. The estimated cancer diagnosis rate among suspicious lesions was 18% (95% CI: 0.13, 0.25). WBMRI detected 41 of the 46 cancers at an early-disease stage, with an overall detection rate of 6% (95% CI: 0.05, 0.08). The incidence rate was 2% per patient round of WBMRI (95% CI: 0.01, 0.04), including baseline and follow-up. CONCLUSION: This meta-analysis provides evidence that surveillance with WBMRI is effective in detecting cancers in asymptomatic patients with LFS. CLINICAL RELEVANCE STATEMENT: Our study demonstrates that whole-body MRI is an effective tool for early cancer detection in asymptomatic Li-Fraumeni Syndrome patients, highlighting its importance in surveillance protocols to improve diagnosis and treatment outcomes. KEY POINTS: Current evidence for whole-body MRI screening of asymptomatic Li-Fraumeni Syndrome (LFS) patients remains scarce. Whole-body MRI identified 41 out of 46 cancers at an early stage, achieving an overall detection rate of 6%. Whole-body MRI surveillance is a valuable method for detecting cancers in asymptomatic LFS patients.

3.
J Toxicol Environ Health A ; 87(18): 752-761, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-38922576

RESUMO

Although the last pandemic created an urgency for development of vaccines, there was a continuous and concerted effort to search for therapeutic medications among existing drugs with different indications. One of the medications of interest that underwent this change was infliximab (IFM). This drug is used as an anti-inflammatory, predominantly in patients with Crohn 's disease, colitis ulcerative, and rheumatoid arthritis. In addition to these patients, individuals infected with Coronavirus Disease (COVID-19) were administered this chimeric monoclonal antibody (IMF) to act as an immunomodulator for patients in the absence of comprehensive research. Consequently, the present study aimed to examine the genotoxic effects attributed to IFM treatment employing different assays in vivo using mouse Mus musculus. Therefore, IFM was found to induce genotoxic effects as evidenced by the comet assay but did not demonstrate genotoxic potential utilizing mouse bone marrow MN test. The results of evaluating the expression of the P53 and BCL-2 genes using RT-qPCR showed stimulation of expression of these genes at 24 hr followed by a decline at 48 hr. Although the comet assay provided positive results, it is noteworthy that based upon negative findings in the micronucleus test, the data did not demonstrate significant changes in the genetic material that might affect the therapeutic use of IFM. The stimulation of expression of P53 and BCL-2 genes at 24 hr followed by a decline at 48 hr suggest a transient, if any, effect on genetic material. However, there is still a need for more research to more comprehensively understand the genotoxic profile of this medication.


Assuntos
Infliximab , Proteína Supressora de Tumor p53 , Animais , Camundongos , Proteína Supressora de Tumor p53/genética , Dano ao DNA/efeitos dos fármacos , Ensaio Cometa , Testes para Micronúcleos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Masculino , Genes p53/efeitos dos fármacos , Genes bcl-2/efeitos dos fármacos
4.
Clinics (Sao Paulo) ; 79: 100415, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38897099

RESUMO

INTRODUCTION: Patients with Human Papillomavirus (HPV+)-associated Laryngeal Squamous Cell Carcinoma (LSCC) exhibit dramatically improved survival relative to those with HPV-Negative (HPV-) tumors. In this study, the authors aimed to investigate the radiosensitivity of all available confirmed HPV+ and HPV-LSCC cells in vitro and in vivo. METHODS: Primary LSCC cells were generated from tumor specimens obtained from patients. Real-time PCR was performed to confirm HPV infection and the expression of HPV-related genes (E6 and E7), p53, and pRB. Clonogenic survival assays, western blotting, and flow cytometry were used to assess radiation sensitivity, apoptosis, and the expression of p53 and pRB. p53 and pRB knockout cells were generated using CRISPR/Cas9 technology. RESULTS: HPV+ LSCC cells displayed enhanced radiation sensitivity compared to HPV- cells. Radiation-induced apoptosis in HPV+ LSCC cells, accompanied by increased levels of p53 and pRB. Knockout of p53 or pRB led to radiation resistance and attenuated radiation-induced apoptosis in HPV+ LSCC cells. In vivo experiments showed similar results, where knockout of p53 or pRB decreased radiosensitivity in tumor-bearing mice. CONCLUSION: The present findings demonstrated that HPV+ LSCC cells displayed obvious inherent radiation sensitivity, corresponding to increased apoptosis following radiation exposure. Mechanism study showed that the expression of p53 and pRB in HPV+ cells are required for radiation sensitivity. These findings highlight a novel mechanism by which p53 and pRB play key roles in the radiation sensitivity of HPV+ LSCC compared to HPV-LSCC.


Assuntos
Apoptose , Carcinoma de Células Escamosas , Neoplasias Laríngeas , Infecções por Papillomavirus , Tolerância a Radiação , Proteína Supressora de Tumor p53 , Humanos , Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/virologia , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/virologia , Proteína Supressora de Tumor p53/metabolismo , Infecções por Papillomavirus/radioterapia , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/complicações , Apoptose/efeitos da radiação , Animais , Linhagem Celular Tumoral , Reação em Cadeia da Polimerase em Tempo Real , Masculino , Camundongos , Citometria de Fluxo , Western Blotting , Proteína do Retinoblastoma/metabolismo
5.
Clin Transl Oncol ; 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38907827

RESUMO

OBJECTIVE: The primary objective of this study is to explore the significance of concurrent evaluation of HER2 gene amplification and p53 and Ki67 expression in gastric cancer tissues. METHODS: Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) methodologies were used to detect HER2 gene amplification, as well as the expression levels of HER2, p53, and Ki67 proteins, across a group of 78 gastric cancer cases. RESULTS: The expression rate of the HER2 protein was determined to be 43.6% (34/78), with 17.9% (14/78) categorized as HER2 protein 3 + , 14.1% (11/78) as HER2 protein 2 + , and 11.5% (9/78) as HER2 protein 1 + . Using FISH technology, the HER2 gene amplification rate was identified as 19.2% (15/78), including 3 cases of HER2 gene cluster amplification, 5 cases of large granular amplification, 4 cases of punctate amplification, and 3 cases of high polysomy. The positive rate of p53 in gastric cancer cells was 52.6% (41/78), with 62.8% (49/78) of patients exhibiting a ki67 proliferation index ≤ 30, and 37.2% (29/78) accounting for a ki67 proliferation index > 30. The expression rates of the HER2 gene, p53, and ki67 in gastric cancer tissues were significantly associated with both gastric cancer staging and lymph node metastasis (P < 0.05). CONCLUSION: The HER2 gene amplification rate and gene copy number exhibit a positive correlation with the expression rates of p53 and ki67. Combining these assessments can provide crucial insights into the assessment of metastatic potential, disease progression, and prognosis of gastric tumor cells. This holds paramount importance in steering the formulation of individualized treatment strategies.

6.
Eur J Obstet Gynecol Reprod Biol ; 298: 192-196, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38788535

RESUMO

OBJECTIVE: Endometrial cancer (EC) treatment changed substantially with the introduction of molecular classification. Low-middle income (LMIC) countries will face barriers to including molecular classification to guide treatment. This study aims to analyse the value of p53 immunohistochemistry to delineate adjuvant treatment in FIGO stages I and II. METHODS: Patients with EC treated between 2010 and 2016 were retrospectively evaluated. Patients included in this analysis must have reviewed FIGO stage I/II high-grade histologies (endometrioid grade 3, serous, clear cell, carcinosarcoma, mixed and undifferentiated). Samples were subjected to p53 immunohistochemistry. Recurrence-free and overall survival were analysed using the Kaplan-Meier method and log-rank test. Cox proportional hazards regression was performed for multivariable analysis. RESULTS: From 2010 to 2016, 265 patients met the inclusion criteria. Patients with aberrant p53 (71.4 %) were associated with older age (59.7 % vs 77.8 % with more than 60 years), relapse (12.5 vs 29.6 %) and death (22.2 vs 46.7 %). The pattern of relapse was not different, with most being at extrapelvic sites (55.5 % vs 62.3 % for p53 wild type and aberrant, respectively). The median overall survival was not reached versus 92.2 months for p53 wild type and aberrant, respectively (p = 0.003). In multivariate analysis, chemotherapy decreased death (p = 0.014) in p53 aberrant tumours, a benefit not seen in the wild-type cohort (p = 0.22). CONCLUSION: This retrospective analysis corroborates the finding of worse outcomes for p53 aberrant tumours in stage I/II EC and the benefit of more aggressive adjuvant treatment (systemic therapy and radiotherapy). Although not ideal as a sole molecular marker, p53 immunohistochemistry could complement the classical anatomopathological features and be part of the decision-making process with patients in LMIC.


Assuntos
Neoplasias do Endométrio , Imuno-Histoquímica , Proteína Supressora de Tumor p53 , Humanos , Feminino , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/terapia , Neoplasias do Endométrio/mortalidade , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/análise , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Quimioterapia Adjuvante , Estadiamento de Neoplasias , Países em Desenvolvimento , Adulto
7.
JBRA Assist Reprod ; 28(3): 471-482, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-38801312

RESUMO

OBJECTIVE: Bisphenol F (BPF) is an endocrinedisrupting chemical, but information about its effect on thyroid hormones has not been fully explored. Omega 3 fatty acids (O3FA), on the other hand, are antioxidant and antiapoptotic agents. Therefore, this study explored the role and associated molecular mechanism of O3FA in BPF-induced hypothyroidism-mediated testicular dysfunction in male Wistar rats. METHODS: Twenty (20) male Wistar rats were randomized into four groups (n=5/group), namely: the control group; the BPF treated group (30 mg/kg of BPF); and the intervention groups (30mg/kg BPF + 100mg/kg O3FA (BPF+O3FA-L) and 30mg/kg BPF + 300mg/kg of O3FA for 28 days). RESULTS: Low and high doses of O3FA ameliorated BPF-induced hypothyroidism-mediated reduction in sperm quality, testosterone, luteinizing hormone, follicle-stimulating hormone, catalase, superoxide dismutase, total antioxidant capacity, and nuclear factor erythroid 2-related factor 2 and increases in estrogen, malondialdehyde, c-reactive protein, interleukin 1 beta, caspase 3. Furthermore, O3FA prevented BPF-induced Na+/K+-ATPase and Ca2+-ATPase dysfunction, estrogen receptor beta overexpression, and tumor protein P53 (p53)/ b-cell lymphoma 2 (Bcl-2) imbalance. CONCLUSIONS: This study showed that O3FA ameliorated BPF-induced dysthyroidism-mediated testicular dysfunction by preventing proton pump dysfunction and p53/BCl-2 imbalance.


Assuntos
Ácidos Graxos Ômega-3 , Testículo , Proteína Supressora de Tumor p53 , Animais , Masculino , Ratos , Ácidos Graxos Ômega-3/farmacologia , Hipotireoidismo/metabolismo , Hipotireoidismo/induzido quimicamente , Hipotireoidismo/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/metabolismo , Proteína Supressora de Tumor p53/metabolismo
8.
Metabolites ; 14(5)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38786726

RESUMO

The metabolic reprogramming that promotes tumorigenesis in glioblastoma is induced by dynamic alterations in the hypoxic tumor microenvironment, as well as in transcriptional and signaling networks, which result in changes in global genetic expression. The signaling pathways PI3K/AKT/mTOR and RAS/RAF/MEK/ERK stimulate cell metabolism, either directly or indirectly, by modulating the transcriptional factors p53, HIF1, and c-Myc. The overexpression of HIF1 and c-Myc, master regulators of cellular metabolism, is a key contributor to the synthesis of bioenergetic molecules that mediate glioma cell transformation, proliferation, survival, migration, and invasion by modifying the transcription levels of key gene groups involved in metabolism. Meanwhile, the tumor-suppressing protein p53, which negatively regulates HIF1 and c-Myc, is often lost in glioblastoma. Alterations in this triad of transcriptional factors induce a metabolic shift in glioma cells that allows them to adapt and survive changes such as mutations, hypoxia, acidosis, the presence of reactive oxygen species, and nutrient deprivation, by modulating the activity and expression of signaling molecules, enzymes, metabolites, transporters, and regulators involved in glycolysis and glutamine metabolism, the pentose phosphate cycle, the tricarboxylic acid cycle, and oxidative phosphorylation, as well as the synthesis and degradation of fatty acids and nucleic acids. This review summarizes our current knowledge on the role of HIF1, c-Myc, and p53 in the genic regulatory network for metabolism in glioma cells, as well as potential therapeutic inhibitors of these factors.

9.
Int. j. morphol ; 42(2): 356-361, abr. 2024. ilus
Artigo em Inglês | LILACS | ID: biblio-1558142

RESUMO

SUMMARY: Although tacrolimus (TAC) significantly reduces allograft rejection incidence in solid-organ transplantation, its long-term use is associated with an increased risk of TAC-induced nephrotoxicity. In this study, we investigated the renoprotective effects of green tea extract (GTE) with or without the dipeptidyl peptidase 4 inhibitor, gemigliptin, by assessing serum creatinine levels, the amount of proteinuria, and histopathology in TAC-induced nephrotoxicity. TAC-induced nephrotoxicity was induced by intraperitoneal TAC injection, GTE was administered via subcutaneous injection, and gemigliptin was administered orally. Mice with TAC-induced nephrotoxicity exhibited a significant increase in both serum creatinine levels and 24-hour urine protein. However, when treated with GTE via subcutaneous injection, mice showed a decrease in serum creatinine levels and the amount of proteinuria. When GTE was combined with gemigliptin, further renoprotective effects were observed in biochemical assessments, consistent with the attenuation of TAC-induced nephrotoxicity in histopathology. The expression of p53 protein was lower in the mice treated with the combination of GTE and gemigliptin compared to mice with TAC-induced nephrotoxicity. Our results demonstrate that the combination of GTE and gemigliptin treatment reveals synergistic renoprotective effects by decreasing the expression of p53 protein. These findings suggest that the combination of GTE and gemigliptin could potentially be used as a prophylactic or therapeutic strategy for TAC-induced nephrotoxicity.


Aunque tacrolimus (TAC) reduce significativamente la incidencia de rechazo de aloinjertos en trasplantes de órganos sólidos, su uso a largo plazo se asocia con un mayor riesgo de nefrotoxicidad inducida por TAC. En este estudio, investigamos los efectos renoprotectores del extracto de té verde (GTE) con o sin el inhibidor de la dipeptidil peptidasa 4, gemigliptina, mediante la evaluación de los niveles de creatinina sérica, la cantidad de proteinuria y la histopatología en la nefrotoxicidad inducida por TAC. La nefrotoxicidad inducida por TAC se indujo mediante inyección intraperitoneal de TAC, el GTE se administró mediante inyección subcutánea y la gemigliptina se administró por vía oral. Los ratones con nefrotoxicidad inducida por TAC mostraron un aumento significativo tanto en los niveles de creatinina sérica como en la proteína en orina de 24 horas. Sin embargo, cuando se trataron con GTE mediante inyección subcutánea, los ratones mostraron una disminución en los niveles de creatinina sérica y en la cantidad de proteinuria. Cuando se combinó GTE con gemigliptina, se observaron efectos renoprotectores adicionales en las evaluaciones bioquímicas, lo que concuerda con la atenuación de la nefrotoxicidad inducida por TAC en histopatología. La expresión de la proteína p53 fue menor en los ratones tratados con la combinación de GTE y gemigliptina en comparación con los ratones con nefrotoxicidad inducida por TAC. Nuestros resultados demuestran que la combinación de tratamiento con GTE y gemigliptina revela efectos renoprotectores sinérgicos al disminuir la expresión de la proteína p53. Estos hallazgos sugieren que la combinación de GTE y gemigliptina podría usarse potencialmente como estrategia profiláctica o terapéutica para la nefrotoxicidad inducida por TAC.


Assuntos
Animais , Camundongos , Piperidonas/administração & dosagem , Pirimidinas/administração & dosagem , Chá , Extratos Vegetais/administração & dosagem , Tacrolimo/toxicidade , Nefropatias/tratamento farmacológico , Piperidonas/farmacologia , Pirimidinas/farmacologia , Extratos Vegetais/farmacologia , Substâncias Protetoras , Sinergismo Farmacológico , Imunossupressores/toxicidade , Rim/efeitos dos fármacos , Nefropatias/induzido quimicamente
10.
Rev. chil. obstet. ginecol. (En línea) ; Rev. chil. obstet. ginecol;89(2): 77-84, abr. 2024. tab
Artigo em Espanhol | LILACS | ID: biblio-1559732

RESUMO

Introducción: El cáncer de endometrio ocupa el sexto lugar en incidencia del cáncer en mujeres. La caracterización molecular de este cáncer permite optimizar la estratificación de riesgo para mejorar el tratamiento de las pacientes. Objetivo: Determinar el perfil molecular TCGA de pacientes con cáncer de endometrio en Bogotá, D.C., Colombia. Método: Estudio descriptivo en una cohorte de pacientes con cáncer de endometrio. Las mutaciones en los exones 9 a 14 del gen POLE fueron identificadas mediante amplificación por reacción en cadena de la polimerasa, seguida de secuenciación Sanger y análisis bioinformático. La expresión de las proteínas MMR y p53 se identificó mediante inmunohistoquímica. Resultados: Se incluyeron 40 pacientes con una mediana de edad de 66 años. El 15% presentaron mutaciones en el dominio exonucleasa de POLE. El 32% de las pacientes que no presentaron mutaciones manifestaron deficiencia en el sistema MMR. El 43,47% de las pacientes sin mutaciones en POLE ni alteración del sistema MMR presentaron alteración de la proteína p53. Conclusiones: La población de cáncer de endometrio analizada presenta un perfil molecular TCGA similar a lo reportado para otras poblaciones.


Introduction: Endometrial cancer ranks sixth in cancer incidence among women. Its molecular characterization allows for a more precise risk stratification with the aim of improving patient treatment. Objective: To determine the TCGA molecular profile of patients with endometrial cancer in Bogota, Colombia. Method: A descriptive study of a cohort of patients with endometrial cancer. The expression of MMR proteins and p53 was identified through immunohistochemistry. Mutations in exons 9 to 14 of the POLE gene were identified through polymerase chain reaction amplification, followed by Sanger sequencing and bioinformatic analysis. Results: Forty patients were included in the study, with a median age of 66 years, 15% of them exhibited mutations in the exonuclease domain of POLE, while 32% of patients without mutations showed deficiency in the MMR system. Forty three percent of patients without mutations in POLE or MMR alterations showed aberrant p53 protein expression. Conclusions: The analyzed population of endometrial cancer presents a TCGA molecular profile similar to that reported for other populations.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Neoplasias do Endométrio/genética , Imuno-Histoquímica , Reação em Cadeia da Polimerase , Estudos Transversais , Estudos Retrospectivos , Genes p53/genética , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/patologia , Análise de Sequência de DNA , Colômbia , Medição de Risco , DNA Polimerase II , Reparo de Erro de Pareamento de DNA , Proteínas de Ligação a Poli-ADP-Ribose , Mutação
11.
Arch Toxicol ; 98(7): 2085-2100, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38619592

RESUMO

Thallium (Tl) and its two cationic species, Tl(I) and Tl(III), are toxic for most living beings. In this work, we investigated the effects of Tl (10-100 µM) on the viability and proliferation capacity of the adherent variant of PC12 cells (PC12 Adh cells). While both Tl(I) and Tl(III) halted cell proliferation from 24 h of incubation, their viability was ~ 90% even after 72 h of treatment. At 24 h, increased levels of γH2AX indicated the presence of DNA double-strand breaks. Simultaneously, increased expression of p53 and its phosphorylation at Ser15 were observed, which were associated with decreased levels of p-AKTSer473 and p-mTORSer2448. At 72 h, the presence of large cytoplasmic vacuoles together with increased autophagy predictor values suggested that Tl may induce autophagy in these cells. This hypothesis was corroborated by images obtained by transmission electron microscopy (TEM) and from the decreased expression at 72 h of incubation of SQSTM-1 and increased LC3ß-II to LC3ß-I ratio. TEM images also showed enlarged ER that, together with the increased expression of IRE1-α from 48 h of incubation, indicated that Tl-induced ER stress preceded autophagy. The inhibition of autophagy flux with chloroquine increased cell mortality, suggesting that autophagy played a cytoprotective role in Tl toxicity in these cells. Together, results indicate that Tl(I) or Tl(III) are genotoxic to PC12 Adh cells which respond to the cations inducing ER stress and cytoprotective autophagy.


Assuntos
Autofagia , Proliferação de Células , Sobrevivência Celular , Estresse do Retículo Endoplasmático , Tálio , Autofagia/efeitos dos fármacos , Células PC12 , Animais , Ratos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Tálio/toxicidade , Proliferação de Células/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Fosforilação , Microscopia Eletrônica de Transmissão
12.
Rev Esp Patol ; 57(2): 128-132, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38599733

RESUMO

Primary hepatic liposarcoma is an extremely rare malignant tumour derived from adipocytes and is part of the group of mesenchymal tumours. We present the case of a 43-year-old Hispanic male patient with a pleomorphic hepatic liposarcoma and absence of MDM2 gene amplification. Two years and six months after surgery, the patient is asymptomatic. The present case is the first report of this entity with positive immunohistochemical testing for p16, p53, S100, vimentin and absence of MDM2 gene amplification.


Assuntos
Lipossarcoma , Proteínas Proto-Oncogênicas c-mdm2 , Humanos , Masculino , Adulto , Proteínas Proto-Oncogênicas c-mdm2/genética , Lipossarcoma/patologia , Adipócitos/patologia
13.
bioRxiv ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38617260

RESUMO

Pathogenic germline TP53 alterations cause Li-Fraumeni Syndrome (LFS), and breast cancer is the most common cancer in LFS females. We performed first of its kind multimodal analysis of LFS breast cancer (LFS-BC) compared to sporadic premenopausal BC. Nearly all LFS-BC underwent biallelic loss of TP53 with no recurrent oncogenic variants except ERBB2 (HER2) amplification. Compared to sporadic BC, in situ and invasive LFS-BC exhibited a high burden of short amplified aneuploid segments (SAAS). Pro-apoptotic p53 target genes BAX and TP53I3 failed to be up-regulated in LFS-BC as was seen in sporadic BC compared to normal breast tissue. LFS-BC had lower CD8+ T-cell infiltration compared to sporadic BC yet higher levels of proliferating cytotoxic T-cells. Within LFS-BC, progression from in situ to invasive BC was marked by an increase in chromosomal instability with a decrease in proliferating cytotoxic T-cells. Our study uncovers critical events in mutant p53-driven tumorigenesis in breast tissue.

14.
Chin J Integr Med ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652227

RESUMO

OBJECTIVE: To investigate the mechanism of induction of ferroptosis by brazilin in breast cancer cells. METHODS: Breast cancer 4T1 cells were divided into 6 groups: control, brazilin 1/2 half maximal inhibitory concentration (IC50), IC50, 2×IC50, erastin (10 µg/mL) and capecitabine (10 µg/mL) groups. The effect of brazilin on the proliferation of 4T1 cells was detected by cell counting kit-8 assay, and the treatment dose of brazilin was screened. The effect of brazilin on the mitochondrial morphology of 4T1 cells, and the mitochondrial damage was evaluated under electron microscopy. The levels of Fe2+, reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH) and glutathione peroxidase 4 (GPX4) were estimated using various detection kits. The invasion and migration abilities of 4T1 cells were detected by scratch assay and transwell assay. The expressions levels of tumor protein p53, solute carrier family 7 member 11 (SLC7A11), GPX4 and acyl-CoA synthetase long-chain family member 4 (ACSL4) proteins were quantified by Western blot assay. RESULTS: Compared to the control group, the 10 (1/2 IC50), 20 (IC50) and 40 (2×IC50) µg/mL brazilin, erastin, and capecitabine groups showed a significant decrease in the cell survival rate, invasion and migration abilities, GSH, SLC7A11 and GPX4 protein expression levels, and mitochondrial volume and ridge (P<0.05), and a significant increase in the mitochondria membrane density, Fe2+, ROS and MDA levels, and p53 and ACSL4 protein expression levels (P<0.05). CONCLUSIONS: Brazilin actuated ferroptosis in breast cancer cells, and the underlying mechanism is mainly associated with the p53/SLC7A11/GPX4 signaling pathway.

15.
Hered Cancer Clin Pract ; 22(1): 1, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238849

RESUMO

BACKGROUND: Li-Fraumeni syndrome (LFS) is an autosomal dominant hereditary cancer syndrome caused by pathogenic variants in the gene TP53. This gene codes for the P53 protein, a crucial player in genomic stability, which functions as a tumor suppressor gene. Individuals with LFS frequently develop multiple primary tumors at a young age, such as soft tissue sarcomas, breast cancer, and brain tumors. CASE PRESENTATION: A 38 years-old female with a history of femur osteosarcoma, ductal carcinoma of the breast, high-grade breast sarcoma, pleomorphic sarcoma of the left upper limb, infiltrating lobular carcinoma of the breast, gastric adenocarcinoma, leiomyosarcoma of the right upper limb, and high-grade pleomorphic renal sarcoma. Complete molecular sequencing of the TP53 gene showed c.586 C > T (p.R196X) in exon 6, which is a nonsense mutation that produces a shorter and malfunctioning P53. Family history includes advanced father's age at the time of conception (75 years), which has been associated with an increased risk of de novo germline mutations. The patient had seven paternal half-siblings with no cancer history. The patient received multiple treatments including surgery, systemic therapy, and radiotherapy, but died at the age of 38. CONCLUSIONS: Advanced paternal age is a risk factor to consider when hereditary cancer syndrome is suspected. Early detection of hereditary cancer syndromes and their multi-disciplinary surveillance and treatment is important to improve clinical outcomes for these patients. Further investigation of the relationship between the pathogenic variant of TP53 and its phenotype may guide the stratification of surveillance and treatment.

16.
Clinics ; Clinics;79: 100415, 2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1569148

RESUMO

Abstract Introduction: Patients with Human Papillomavirus (HPV+)-associated Laryngeal Squamous Cell Carcinoma (LSCC) exhibit dramatically improved survival relative to those with HPV-Negative (HPV-) tumors. In this study, the authors aimed to investigate the radiosensitivity of all available confirmed HPV+ and HPV-LSCC cells in vitro and in vivo. Methods: Primary LSCC cells were generated from tumor specimens obtained from patients. Real-time PCR was performed to confirm HPV infection and the expression of HPV-related genes (E6 and E7), p53, and pRB. Clonogenic survival assays, western blotting, and flow cytometry were used to assess radiation sensitivity, apoptosis, and the expression of p53 and pRB. p53 and pRB knockout cells were generated using CRISPR/Cas9 technology. Results: HPV+ LSCC cells displayed enhanced radiation sensitivity compared to HPV- cells. Radiation-induced apoptosis in HPV+ LSCC cells, accompanied by increased levels of p53 and pRB. Knockout of p53 or pRB led to radiation resistance and attenuated radiation-induced apoptosis in HPV+ LSCC cells. In vivo experiments showed similar results, where knockout of p53 or pRB decreased radiosensitivity in tumor-bearing mice. Conclusion: The present findings demonstrated that HPV+ LSCC cells displayed obvious inherent radiation sensitivity, corresponding to increased apoptosis following radiation exposure. Mechanism study showed that the expression of p53 and pRB in HPV+ cells are required for radiation sensitivity. These findings highlight a novel mechanism by which p53 and pRB play key roles in the radiation sensitivity of HPV+ LSCC compared to HPV-LSCC.

17.
Cells ; 12(21)2023 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-37947651

RESUMO

Capsaicinoids are a unique chemical species resulting from a particular biosynthesis pathway of hot chilies (Capsicum spp.) that gives rise to 22 analogous compounds, all of which are TRPV1 agonists and, therefore, responsible for the pungency of Capsicum fruits. In addition to their human consumption, numerous ethnopharmacological uses of chili have emerged throughout history. Today, more than 25 years of basic research accredit a multifaceted bioactivity mainly to capsaicin, highlighting its antitumor properties mediated by cytotoxicity and immunological adjuvancy against at least 74 varieties of cancer, while non-cancer cells tend to have greater tolerance. However, despite the progress regarding the understanding of its mechanisms of action, the benefit and safety of capsaicinoids' pharmacological use remain subjects of discussion, since CAP also promotes epithelial-mesenchymal transition, in an ambivalence that has been referred to as "the double-edge sword". Here, we update the comparative discussion of relevant reports about capsaicinoids' bioactivity in a plethora of experimental models of cancer in terms of selectivity, efficacy, and safety. Through an integration of the underlying mechanisms, as well as inherent aspects of cancer biology, we propose mechanistic models regarding the dichotomy of their effects. Finally, we discuss a selection of in vivo evidence concerning capsaicinoids' immunomodulatory properties against cancer.


Assuntos
Capsicum , Neoplasias , Humanos , Capsaicina/farmacologia , Frutas/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Biologia
18.
J Cell Commun Signal ; 17(4): 1389-1403, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37982965

RESUMO

Aberrant canonical Wnt signaling is a hallmark of colon cancer. The TP53 tumor suppressor gene is altered in many solid tumors, including colorectal cancer, resulting in mutant versions of p53 (mut-p53) that lose their tumor suppressor capacities and acquire new-oncogenic functions (GOFs) critical for disease progression. Although the mechanisms related to mut-p53 GOF have been explored extensively, the relevance of mut-p53 in the canonical Wnt pathway is not well defined. This work investigated the influence of mut-p53 compared to wt-p53 in ß-catenin-dependent Wnt signaling. Using the TCGA public data from Pan-Cancer and the GEPIA2 platform, an in silico analysis of wt-p53 versus mut-p53 genotyped colorectal cancer patients showed that TP53 (p53) and CTNNB1 (ß-catenin) are significantly overexpressed in colorectal cancer, compared with normal tissue. Using p53 overexpression or p53 knockdown assays of wt-p53 or mut-p53, we found that while wt-p53 antagonizes canonical Wnt signaling, mut-p53 induces the opposite effect, improving the ß-catenin-dependent transcriptional activity and colony formation ability of colon cancer cells, which were both decreased by mut-p53 knockdown expression. The mechanism involved in mut-p53-induced activation of canonical Wnt appears to be via AKT-mediated phosphorylation of Ser 552 of ß-catenin, which is known to stabilize and enhance its transcriptional activity. We also found that while wt-p53 expression contributes to 5-FU sensitivity in colon cancer cells, the RITA p53 reactivating molecule counteracted the resistance against 5-FU in cells expressing mut-p53. Our results indicate that mut-p53 GOF acts as a positive regulator of canonical Wnt signaling and participates in the induction of resistance to 5-FU in colon cancer cells.

19.
Plants (Basel) ; 12(21)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37960113

RESUMO

The main objective of research into new therapies is the search for more efficacy and fewer toxic effects in cancer treatments. On one hand, vincristine (VCR) is a chemotherapeutic used in different kinds of tumors. On the other hand, epigallocatechin gallate (EGCG) is a green tea metabolite that has shown an antineoplastic effect in diverse investigations, so the objective of this work is to evaluate the antitumor effects of the EGCG/VCR combination on tumor volume and survival. To achieve this objective, the solid model of lymphoma L5178Y was used in BALB/c mice with different doses of VCR, EGCG, and their combination allowed tumor growth and survival time recording. After tumor collection, measurements, and immunohistochemistry for p53, Bcl2, and Cyclin D1 were performed. The results showed that the EGCG/vincristine combination had a greater antitumor effect than those effects of vincristine and EGCG. It can be attributed to the fact that the greatest inhibition of Bcl2 was present in gathering of EGCG harvest with vincristine. Therefore, the combination of EGCG with vincristine has a better antineoplastic effect by inhibiting tumor development and increasing survival on both substances independently.

20.
Cells ; 12(20)2023 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-37887350

RESUMO

The master-key TP53 gene is a tumor suppressor that is mutated in more than 50% of human cancers. Some p53 mutants lose their tumor suppressor activity and acquire new oncogenic functions, known as a gain of function (GOF). Recent studies have shown that p53 mutants can exert oncogenic effects through specific miRNAs. We identified the differentially expressed miRNA profiles of the three most frequent p53 mutants (p53R273C, p53R248Q, and p53R175H) after their transfection into the Saos-2 cell line (null p53) as compared with p53WT transfected cells. The associations between these miRNAs and the signaling pathways in which they might participate were identified with miRPath Software V3.0. QRT-PCR was employed to validate the miRNA profiles. We observed that p53 mutants have an overall negative effect on miRNA expression. In the global expression profile of the human miRNome regulated by the p53R273C mutant, 72 miRNAs were underexpressed and 35 overexpressed; in the p53R175H miRNAs profile, our results showed the downregulation of 93 and upregulation of 10 miRNAs; and in the miRNAs expression profile regulated by the p53R248Q mutant, we found 167 decreased and 6 increased miRNAs compared with p53WT. However, we found overexpression of some miRNAs, like miR-182-5p, in association with processes such as cell migration and invasion. In addition, we explored whether the induction of cell migration and invasion by the p53R48Q mutant was dependent on miR-182-5p because we found overexpression of miR-182-5p, which is associated with processes such as cell migration and invasion. Inhibition of mutant p53R248Q and miR-182-5p increased FOXF2-MTSS1 levels and decreased cell migration and invasion. In summary, our results suggest that p53 mutants increase the expression of miR-182-5p, and this miRNA is necessary for the p53R248Q mutant to induce cell migration and invasion in a cancer cell model.


Assuntos
Genes p53 , MicroRNAs , Humanos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular Tumoral , Mutação com Ganho de Função , Proliferação de Células , MicroRNAs/metabolismo , Processos Neoplásicos , Fatores de Transcrição Forkhead/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteínas de Neoplasias/metabolismo
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