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BACKGROUND: This systematic review and meta-analysis investigated the relationship between somatic TP53 oncogenic variants and prognosis, specifically with overall survival (OS) and progression-free survival (PFS) in patients diagnosed with supratentorial glioblastoma. METHODS: We included longitudinal studies and clinical trials involving a minimum of 40 adult participants diagnosed with supratentorial glioblastoma, wherein the status of TP53 variants was assessed. We conducted searches in multiple databases. We assessed bias risk using a modified version of the Quality in Prognosis Studies tool, and the certainty of evidence was evaluated following the principles of the GRADE approach. RESULTS AND CONCLUSION: This study encompassed 23 papers involving 2,555 patients, out of which 716 had reported oncogenic variants. TP53 oncogenic variants were associated with a reduced likelihood of 1-year survival (OR 0.52, 95% CI 0.29-0.94). However, our analysis did not reveal any significant impact of TP53 variants on overall survival, progression-free survival, or 2-year survival. Therefore, this comprehensive analysis demonstrates that the presence of genetic variants in TP53 does not provide useful information for the prognosis of glioblastoma. SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/prospero/, identifier CRD42021289496.

Background: This systematic review and meta-analysis investigated the relationship between somatic TP53 oncogenic variants and prognosis, specifically with overall survival (OS) and progression-free survival (PFS) in patients diagnosed with supratentorial glioblastoma. Methods: We included longitudinal studies and clinical trials involving a minimum of 40 adult participants diagnosed with supratentorial glioblastoma, wherein the status of TP53 variants was assessed. We conducted searches in multiple databases. We assessed bias risk using a modified version of the Quality in Prognosis Studies tool, and the certainty of evidence was evaluated following the principles of the GRADE approach. Results and conclusion: This study encompassed 23 papers involving 2,555 patients, out of which 716 had reported oncogenic variants. TP53 oncogenic variants were associated with a reduced likelihood of 1-year survival (OR 0.52, 95% CI 0.29–0.94). However, our analysis did not reveal any significant impact of TP53 variants on overall survival, progression-free survival, or 2-year survival. Therefore, this comprehensive analysis demonstrates that the presence of genetic variants in TP53 does not provide useful information for the prognosis of glioblastoma. Systematic review registration: https://www.crd.york.ac.uk/prospero/ , identifier CRD42021289496. [ABSTRACT FROM AUTHOR]

Abstract Background Germ-line mutations of the TP53 gene are known to cause Li-Fraumeni syndrome, an autosomal, dominantly inherited, high-penetrance cancer-predisposition syndrome characterized by the occurrence of a variety of cancers, mainly soft tissue sarcomas, adrenocortical carcinoma, leukemia, breast cancer, and brain tumors. Methods Mutation analysis was based on Denaturing high performance liquid chromatography (DHPLC) screening of exons 2-11 of the TP53 gene, sequencing, and cloning of DNA obtained from peripheral blood lymphocytes. Results We report herein on Li Fraumeni syndrome in a family whose members are carriers of a novel TP53 gene mutation at exon 4. The mutation comprises an insertion/duplication of seven nucleotides affecting codon 110 and generating a new nucleotide sequence and a premature stop codon at position 150. With this mutation, the p53 protein that should be translated lacks the majority of the DNA binding domain. Conclusion To our knowledge, this specific alteration has not been reported previously, but we believe it is the cause of the Li-Fraumeni syndrome in this family.

Abstract Background Despite significant achievements in the treatment of cervical cancer, it is still a deadly disease; hence newer therapeutical modalities are needed. Preliminary investigations suggest that platelet-derived growth factor (PDGF) might have a role in the development of cervical cancer, therefore it is important to determine whether this growth factor pathway is functional and its targeting with imatinib mesylate leads to growth inhibition of cervical cancer cells. Results PDGF receptors (PDGFR) and their ligands are frequently expressed in cervical cancer and the majority exhibited a combination of family members co-expression. A number of intronic and exonic variations but no known mutations in the coding sequence of the PDGFRα gene were found in cancer cell lines and primary tumors. Growth assays demonstrated that PDGFBB induces growth stimulation that can be blocked by imatinib and that this tyrosine kinase inhibitor on its own inhibits cell growth. These effects were associated with the phosphorylation status of the receptor. Conclusion The PDGFR system may have a role in the pathogenesis of cervical cancer as their members are frequently expressed in this tumor and cervical cancer lines are growth inhibited by the PDGFR antagonist imatinib.

Abstract Background The development of resistance to cytotoxic chemotherapy continues to be a major obstacle for successful anticancer therapy. It has been shown that cells exposed to toxic concentrations of commonly used cancer chemotherapy agents develop DNA hypermetylation. Hence, demethylating agents could play a role in overcoming drug resistance. Methods MCF-7 cells were rendered adriamycin-resistant by weekly treatment with adriamycin. Wild-type and the resulting MCF-7/Adr cells were analyzed for global DNA methylation. DNA methyltransferase activity and DNA methyltransferase (dnmt) gene expression were also determined. MCF-7/Adr cells were then subjected to antisense targeting of dnmt1, -3a, and -b genes and to treatment with the DNA methylation inhibitor hydralazine to investigate whether DNA demethylation restores sensitivity to adriamycin. Results MCF-7/Adr cells exhibited the multi-drug resistant phenotype as demonstrated by adriamycin resistance, mdr1 gene over-expression, decreased intracellular accumulation of adriamycin, and cross-resistance to paclitaxel. The mdr phenotype was accompanied by global DNA hypermetylation, over-expression of dnmt genes, and increased DNA methyltransferase activity as compared with wild-type MCF-7 cells. DNA demethylation through antisense targeting of dnmts or hydralazine restored adriamycin sensitivity of MCF-7/Adr cells to a greater extent than verapamil, a known inhibitor of mdr protein, suggesting that DNA demethylation interferes with the epigenetic reprogramming that participates in the drug-resistant phenotype. Conclusion We provide evidence that DNA hypermethylation is at least partly responsible for development of the multidrug-resistant phenotype in the MCF-7/Adr model and that hydralazine, a known DNA demethylating agent, can revert the resistant phenotype.

Abstract Hydralazine was one of the first orally active antihypertensive drugs developed. Currently, it is used principally to treat pregnancy-associated hypertension. Hydralazine causes two types of side effects. The first type is an extension of the pharmacologic effect of the drug and includes headache, nausea, flushing, hypotension, palpitation, tachycardia, dizziness, and salt retention. The second type of side effects is caused by immunologic reactions, of which the drug-induced lupus-like syndrome is the most common, and provides clues to underscoring hydralazine's DNA demethylating property in connection with studies demonstrating the participation of DNA methylation disorders in immune diseases. Abnormalities in DNA methylation have long been associated with cancer. Despite the fact that malignant tumors show global DNA hypomethylation, regional hypermethylation as a means to silence tumor suppressor gene expression has attracted the greatest attention. Reversibility of methylation-induced gene silencing by pharmacologic means, which in turns leads to antitumor effects in experimental and clinical scenarios, has directed efforts toward developing clinically useful demethylating agents. Among these, the most widely used comprise the nucleosides 5-azacytidine and 2'deoxy-5-azacytidine; however, these agents, like current cytotoxic chemotherapy, causes myelosuppression among other side effects that could limit exploitation of their demethylating properties. Among non-nucleoside DNA demethylating drugs currently under development, the oral drug hydralazine possess the ability to reactivate tumor suppressor gene expression, which is silenced by promoter hypermethylation in vitro and in vivo. Decades of extensive hydralazine use for hypertensive disorders that demonstrated hydralazine's clinical safety and tolerability supported its testing in a phase I trial in patients with cancer, confirming its DNA demethylating activity. Hydralazine is currently being evaluated, along with histone deacetylase inhibitors either alone or as adjuncts to chemotherapy and radiation, for hematologic and solid tumors in phase II studies.

Abstract Background Among the epigenetic alterations occurring in cancer, DNA hypermethylation and histone hypoacetylation are the focus of intense research because their pharmacological inhibition has shown to produce antineoplastic activity in a variety of experimental models. The objective of this study was to evaluate the combined antineoplastic effect of the DNA methylation inhibitor hydralazine and the histone deacetylase inhibitor valproic acid in a panel of cancer cell lines. Results Hydralazine showed no growth inhibitory effect on cervical, colon, breast, sarcoma, glioma, and head & neck cancer cell lines when used alone. On the contrary, valproic acid showed a strong growth inhibitory effect that is potentiated by hydralazine in some cell lines. Individually, hydralazine and valproic acid displayed distinctive effects upon global gene over-expression but the number of genes over-expressed increased when cells were treated with the combination. Treatment of HeLa cells with hydralazine and valproic acid lead to an increase in the cytotoxicity of gemcitabine, cisplatin and adriamycin. A higher antitumor effect of adriamycin was observed in mice xenografted with human fibrosarcoma cells when the animals were co-treated with hydralazine and valproic acid. Conclusion Hydralazine and valproic acid, two widely used drugs for cardiovascular and neurological conditions respectively have promising antineoplastic effects when used concurrently and may increase the antitumor efficacy of current cytotoxic agents.

Abstract Background The development of cancer has been associated with epigenetic alterations such as aberrant histone deacetylase (HDAC) activity. It was recently reported that valproic acid is an effective inhibitor of histone deacetylases and as such induces tumor cell differentiation, apoptosis, or growth arrest. Methods Twelve newly diagnosed patients with cervical cancer were treated with magnesium valproate after a baseline tumor biopsy and blood sampling at the following dose levels (four patients each): 20 mg/kg; 30 mg/kg, or 40 mg/kg for 5 days via oral route. At day 6, tumor and blood sampling were repeated and the study protocol ended. Tumor acetylation of H3 and H4 histones and HDAC activity were evaluated by Western blot and colorimetric HDAC assay respectively. Blood levels of valproic acid were determined at day 6 once the steady-state was reached. Toxicity of treatment was evaluated at the end of study period. Results All patients completed the study medication. Mean daily dose for all patients was 1,890 mg. Corresponding means for the doses 20-, 30-, and 40-mg/kg were 1245, 2000, and 2425 mg, respectively. Depressed level of consciousness grade 2 was registered in nine patients. Ten patients were evaluated for H3 and H4 acetylation and HDAC activity. After treatment, we observed hyperacetylation of H3 and H4 in the tumors of nine and seven patients, respectively, whereas six patients demonstrated hyperacetylation of both histones. Serum levels of valproic acid ranged from 73.6–170.49 μg/mL. Tumor deacetylase activity decreased in eight patients (80%), whereas two had either no change or a mild increase. There was a statistically significant difference between pre and post-treatment values of HDAC activity (mean, 0.36 vs. 0.21, two-tailed t test p < 0.0264). There was no correlation between H3 and H4 tumor hyperacetylation with serum levels of valproic acid. Conclusion Magnesium valproate at a dose between 20 and 40 mg/kg inhibits deacetylase activity and hyperacetylates histones in tumor tissues.

Anti-HER2 therapy has shown benefit in breast and gastric cancers that over-express HER2; therefore, it is critical to determine whether HER2 is over-expressed and amplified in cervical cancer with current FDA-approved tests, as previous works have reported frequencies of over-expression varying from 0% to 77%. We analyzed 100 consecutive patients starting in January 2013. Patients were previously untreated and diagnosed with locally advanced cervical cancer. They received chemoradiation as definitive treatment. We analyzed their primary tumors with HercepTest and HER-2/neu FISH probe, observing a strong adherence to the testing and reporting recommendations for HER2 testing in breast cancer by the American Society of Clinical Oncology. Among 100 patients, accrued 88 had both tests performed. We found 26 (29.5%) FISH-positive cases. HercepTest scores rating 0+, 1+, 2+, and 3+ were observed in 65.3%, 11.5%, 7.6% and 15.3% in the 26 FISH-positive. There was no concordance between the results of both tests using Cohen's Kappa statistics, neither correlation between FISH status with age, FIGO stage, and response. FISH-positive patients had a non-statistical significant trend for worst 4-year survival. The HER2 protein is over-expressed in only a small subset of invasive cervical cancer as analyzed by Hercept test. Unexpectedly, HER2 gene amplification occurred in around 29.5% of cases. We stress that analyzed HER2 status with the validated methods for the procedures and reports used for breast cancer. Our results must be seen with caution and must encourage further testing in a higher number of patients and different populations to confirm our findings. [ABSTRACT FROM AUTHOR]