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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 The methylation status at the human papilloma virus (HPV) genome found in pre-invasive and invasive cervical lesions suggests that neoplastic transformation can be suppressed by gene hypermethylation, whereas hypomethylation accompanies or causes cancer progression; hence, epigenetic therapy aimed at reactivating cellular suppressor-gene expression has the potential to act as a tumor promoter by enhancing HPV oncoprotein expression in HPV-related malignancies. The objective of this study was to determine the influence of hydralazine and valproate on HPV oncogene expression in cervical cancer cell lines and the primary tumors of patients undergoing treatment with hydralazine and valproate. Results Overall, hydralazine and valproate either alone or combined exerted a growth inhibitory effect on cervical cancer cell lines. A cell line-specific up-regulating effect was observed on E6/E7 gene expression, which in general correlated with DNA hypomethylation and histone acetylation at the long control region (LCR). Nonetheless, E6/E7 expression was unchanged or decreased in the majority of patients with cervical cancer treated with hydralazine, valproate, or both. In some cervical cancer cell lines, these drugs led to increased transcription of p53, and increased its stabilization due to acetylation at lysines 273 and 282, which allowed a higher bax-protein transactivating effect. Conclusion The results of this study demonstrate that hydralazine and valproate can be safely administered to HPV-related malignancies such as cervical cancer because they do not increase viral oncoprotein expression. Most importantly, the antitumor effect of hydralazine and valproate in cervical cancer may at least partially depend on an up-regulating effect on p53 gene and on the valproate-induced hyperacetylation of p53 protein, protecting it from degradation by E6.

Abstract Background DNA hypermethylation and histone deacetylation are epigenetic events that contribute to the absence or downregulated expression of different components of the tumor recognition complex. These events affect the processing and presentation of antigenic peptides to CTLs by HLA class-I molecules. In this work evaluated the effect of the DNA hypomethylating agent hydralazine and the histone deacetylase inhibitor valproic acid, on the expression of HLA class-I molecules and on the antigen-specific immune recognition of cervical cancer cells. Methods Cell lines C33A (HPV-), CaSki (HPV-16+) and MS751 (HPV-18+) were treated with hydralazine and valproic acid to assess the expression of HLA class-I molecules by flow cytometry and RT-PCR. Promoter methylation of HLA class-I -A, -B and C, was also evaluated by Methylation-Specific PCR. Primary cervical tumors of four HLA-A*0201 allele patients were typed for HPV and their CTL's stimulated in vitro with the T2 cell line previously loaded with 50 μM of the HPV peptides. Cytotoxicity of stimulated CTL's was assayed against Caski and MS751 cells pre-treated with hydralazine and valproic acid. Results Valproic acid and hydralazine/valproic acid up-regulated the constitutive HLA class-I expression as evaluated by flow cytometry and RT-PCR despite constitutive promoter demethylation at these loci. Hydralazine and valproic acid in combination but no IFN-gamma hyperacetylated histone H4 as evaluated by ChiP assay. The antigenic immune recognition of CaSki and MS751 cells by CTLs specific to HPV-16/18 E6 and E7-derived epitopes, was increased by VA and H/VA and the combination of H/VA/IFN-gamma. Conclusion These results support the potential use of hydralazine and valproic acid as an adjuvant for immune intervention in cervical cancer patients whenever clinical protocols based on tumor antigen recognition is desirable, like in those cases where the application of E6 and E7 based therapeutic vaccines is used.

Objective: To investigate the relationship between anthropometric, biochemical, and hematologic parameters and serum leptin and homocysteine (Hcy) levels. Also, to determine the effect of leptin and Hcy on expression of genes associated with cardiovascular disease susceptibility (APOA1, LRP1, COX-1, and COX-2) in mononuclear cells of healthy pregnant women., Methods: Between August 2018 and January 2020, a cross-sectional study was conducted on 161 healthy pregnant women in Tabasco, southeastern Mexico. The study population was classified by trimester, according to gestational pregnancy. Anthropometric, biochemical (leptin and homocysteine), and hematologic data were obtained under fasting conditions. APOA1, LRP1, COX-1, and COX-2 expression in mononuclear cells was evaluated using RT-qPCR., Results: Red cell indices (hemoglobin, hematocrit, and erythrocytes) were negatively and positively correlated with leptin and Hcy levels, respectively, in the first- and second-trimester groups. Increased leptin levels and low red cell indices were significantly associated with BMI <25.0 in the second-trimester group; however, no significant differences were observed in Hcy levels. Increased leptin and Hcy levels were significantly associated with high lipid indicators in the first- and third-trimester groups, respectively. High APOA1 and COX-2 expression was significantly associated with reduced leptin and increased Hcy levels in the second- and third-trimester groups., Conclusion: Increased leptin and Hcy levels during pregnancy, mainly associated with modifications in erythrocytes and lipid indices, may lead to early modification of genes related to lipid metabolism (APOA1) and proinflammatory response (COX-2) and, thereby, increase cardiovascular disease risk., (© 2023 International Federation of Gynecology and Obstetrics.)

Increased homocysteine (Hcy) levels have been associated with a higher risk of cardiovascular and neurodegenerative diseases. Passive DNA demethylation has been suggested as one of the mechanisms implicated in the development of these conditions, and most studies have investigated this relationship in older adult populations. Therefore, this study aimed to evaluate the relationship between corporal composition and biochemical and haematological indicators with plasma homocysteine levels and genome-wide methylation (Alu, LINE-1, and SAT2) in a population of healthy young adults (median age, 18 years). We showed that the prevalence of hyperhomocysteinemia was significantly higher in men (18.5%) than in women (6.6%) ( P = 0.034). Increased Hcy level was substantially associated with higher levels of body mass index and visceral fat in females, whereas in males, it was significantly associated with reduced red cell distribution width and high-density lipoprotein (HDL) cholesterol (HDL-C) levels and increased low-density lipoprotein/HDL ratio. Hypomethylation of Alu was significantly associated with reduced levels of HDL-C (<40.0 mg dL -1 ), whereas hypomethylation of LINE-1 and SAT2 was significantly associated with higher levels of skeletal muscle (<39.3%) in males. These results highlight the participation of hormonal factors in regulating Hcy metabolism, primarily in the female population, whereas changes in DNA methylation observed in males might be associated with the consumption of a protein diet with high levels of methionine, independent of increased Hcy levels.

Previous studies have proposed that the human papillomavirus (HPV) E6 oncoproteins modify the transcriptional activity of eIF4E through mechanisms dependent on p53 degradation. However, the effect of these oncoproteins on pathways regulating the activity of the eIF4E protein remains poorly understood. Hence, we investigated the mechanisms whereby E6 proteins regulate the activity of the eIF4E protein and its effect on target genes. Overexpression of E6 constructs (HPV-6, HPV-16, HPV-18, and HPV52) showed that E6 oncoproteins increased phosphorylation of the eIF4E protein (Serine-209). This result was mainly mediated by phosphorylation of the 4EBP1 protein via the PI3K/AKT pathway. Additionally, the pharmacological inhibition of eIF4E phosphorylation in cervical cancer cell lines substantially reduced the protein levels of CCND1 and ODC1, indicating that E6 of the high-risk genotypes may modify protein synthesis of the eIF4E target genes by increasing the activity of the AKT and ERK pathways., (© 2020 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.)

Introduction . Bacterial vaginosis (BV) is dysbiosis associated with an increased risk of several sexually transmitted infections. It is primarily diagnosed via Gram staining, although molecular analyses have presented higher diagnostic accuracy. Aim . This study aimed to evaluate the molecular epidemiology of BV in asymptomatic women to determine its association with several commensal and pathogenic micro-organisms of the genitalia. Methodology . The prevalence of BV was investigated through semiquantitative assessment of 201 women recruited during their routine gynaecological inspection at an outpatient clinic in Tabasco, Mexico. Results . Women with BV showed an increased prevalence of Chlamydia trachomatis ( P =0.021) and Mycoplasma hominis ( P =0.001). Of the BV-associated micro-organisms, Gardnerella vaginalis was significantly associated with C. trachomatis ( P =0.005) and/or Ureaplasma parvum ( P =0.003 ) , whereas Atopobium vaginae and Megasphaera type 1 correlated significantly with Mycoplasma hominis ( P =0.001). No significant association was observed between human papillomavirus (HPV) infection and BV, although there was increased prevalence of HPV59, HPV73, HPV52 and HPV58 in women displaying cervical cytological abnormalities. Conclusion . Identification of BV-associated micro-organisms via molecular analysis may help to distinguish recurrent cases from new infections and identify micro-organisms potentially associated with pharmacological resistance.

Cervical cancer development has been mainly associated with persistent human papillomavirus (HPV) infections. However, HPV infection is unlikely to be sufficient to cause cervical cancer, and the contribution of other sexually transmitted infections (STIs) could be the determining factor for cervical lesion-progression. The aim of this study was to estimate the prevalence of STIs associated with HPV-positivity in 201 cervical samples from patients who underwent annual routine gynecological exams. The overall prevalence of STIs was 57.7%, and the most frequent infection was Ureaplasma spp (UP) (39.8%), followed by Gardnerella vaginalis (GV) (25.9%), α-HPV (18.4%), Chlamydia trachomatis (CT) (1.5%), and Mycoplasma genitalium (MG) (0.5%). The highest prevalence rate of multiple non-HPV infections was observed for the age-range 31-40; for papillomavirus infection, the age-range was 21-30. In normal cervical samples, HPV16 was the most prevalent genotype (24.3%), followed by genotypes 58 (13.5%) and 52 (10.8%). Intriguingly, HPV18 was not detected in the study population, and genotypes 52 and 58 were found exclusively in samples with abnormal cytology. Papillomavirus infection with oncogenic types was significantly associated with GV (P = 0.025) and strongly associated with multiple non-HPV pathogens (P = 0.002). The following variables correlated significantly with cytological diagnosis of low-grade squamous intraepithelial lesion (LSIL): GV (P = 0.028), multiple non-HPV infections (P = 0.001), and high-risk HPV positivity (P = 0.001). Epidemiological data from this study will contribute to the molecular detection of sexually transmitted pathogens from screening programs to identify those women who are at risk for developing cervical lesions., (© 2015 Wiley Periodicals, Inc.)

The aim of the present study was to demonstrate that ribavirin, a known inhibitor of eIF4E and inosine 5'-phosphate dehydrogenase (IMPDH), also inhibits histone methyltransferase zeste homolog 2 (EZH2). A computational searching revealed that ribavirin has a high structural similarity to 3-deazaneplanocin A (DZNep). The growth inhibitory effects of ribavirin as well as its effects upon epigenetic enzymes were evaluated in various cancer cell lines. siRNA assays were used to downregulate eIF4E, EZH2 and IMPDH to determine the contribution of these targets to the growth inhibitory effects of ribavirin. Ribavirin decreased EZH2 expression, inhibited histone methyltransferase activity and decreased H3K27 trimethylation. Ribavirin induced variable growth inhibition in a number of cell lines and downregulation of the targets, EZH2, eIF4E and IMPDH1 and 2 by siRNA led to comparable growth inhibition while no significant further reduction in viability was observed when siRNA transfected cells were treated with ribavirin. The results showed that ribavirin inhibits these cancer targets and should thus be studied for cancer therapy.

Background: Down regulation of genes coding for nucleoside transporters and drug metabolism responsible for uptake and metabolic activation of the nucleoside gemcitabine is related with acquired tumor resistance against this agent. Hydralazine has been shown to reverse doxorubicin resistance in a model of breast cancer. Here we wanted to investigate whether epigenetic mechanisms are responsible for acquiring resistance to gemcitabine and if hydralazine could restore gemcitabine sensitivity in cervical cancer cells., Methodology/principal Findings: The cervical cancer cell line CaLo cell line was cultured in the presence of increasing concentrations of gemcitabine. Down-regulation of hENT1 & dCK genes was observed in the resistant cells (CaLoGR) which was not associated with promoter methylation. Treatment with hydralazine reversed gemcitabine resistance and led to hENT1 and dCK gene reactivation in a DNA promoter methylation-independent manner. No changes in HDAC total activity nor in H3 and H4 acetylation at these promoters were observed. ChIP analysis showed H3K9m2 at hENT1 and dCK gene promoters which correlated with hyper-expression of G9A histone methyltransferase at RNA and protein level in the resistant cells. Hydralazine inhibited G9A methyltransferase activity in vitro and depletion of the G9A gene by iRNA restored gemcitabine sensitivity., Conclusions/significance: Our results demonstrate that acquired gemcitabine resistance is associated with DNA promoter methylation-independent hENT1 and dCK gene down-regulation and hyper-expression of G9A methyltransferase. Hydralazine reverts gemcitabine resistance in cervical cancer cells via inhibition of G9A histone methyltransferase.

The reversing of epigenetic aberrations using the inhibitors of DNA methylation and histone deacetylases may have therapeutic value in cervical cancer. This is a randomized phase III, placebo-controlled study of hydralazine and valproate (HV) added to cisplatin topotecan in advanced cervical cancer. Patients received hydralazine at 182 mg for rapid, or 83 mg for slow acetylators, and valproate at 30 mg/kg, beginning a week before chemotherapy and continued until disease progression. Response, toxicity, and PFS were evaluated, and 36 patients (17 CT + HV and 19 CT + PLA) were included. The median number of cycles was 6. There were four PRs to CT + HV and one in CT + PLA. Stable disease in five (29%) and six (32%) patients, respectively, whereas eight (47%) and 12 (63%) showed progression (P = 0.27). At a median follow-up time of 7 months (1-22), the median PFS is 6 months for CT + PLA and 10 months for CT + HV (P = 0.0384, two tailed). Although preliminary, this study represents the first randomized clinical trial to demonstrate a significant advantage in progression-free survival for epigenetic therapy over one of the current standard combination chemotherapy in cervical cancer. Molecular correlates with response and survival from this trial are pending to analyze.

Among many anticancer drugs collectively named "targeted or molecular therapies" epigenetic drugs are clearly promising. Differently from other agents targeting a single gene product, epigenetic drugs have chromatin as their target through inhibition of histone deacetylases (HDACs) and DNA methyltransferases (DNMTs) therefore, yet unspecific, they may act upon most or all tumor types, as deregulation of the methylation and deacetylation machinery are a common hallmark of neoplasia. In the last years, valproic acid (VPA) as emerged as a promising drug for cancer treatment. VPA has shown potent antitumor effects in a variety of in vitro and in vivo systems, and encouraging results in early clinical trials either alone or in combination with demethylating and/or cytotoxic agents. In addition, whole genome expression by microarray analysis from the primary tumors of patients treated with VPA show significant up-regulation of hundred of genes belonging to multiple pathways including ribosomal proteins, oxidative phosphorylation, MAPK signaling; focal adhesion, cell cycle, antigen processing and presentation, proteasome, apoptosis, PI3K, Wnt signaling, calcium signaling, TGF-beta signaling, and ubiquitin-mediated proteolysis among others. Despite in general, industry is not particularly interested in funding the clinical development of VPA, -at least in comparison to novel HDAC inhibitors-, existing preclinical and preliminary clinical data strongly suggest that VPA could be a drug that eventually will be used in combination therapies, either with classical cytotoxics, other molecular-targeted drugs or radiation in a number of solid tumors.