TP53 AND C-MYC CO-ALTERATIONS - A HALLMARK OF ORAL CANCER PROGRESSION

Background: Head and neck squamous cell carcinoma, including oral cancer, is the sixth most common cancer worldwide. Despite advances in surgery and treatment, the 5-year survival rate has not improved significantly. There fore, reliable molecular markers for oral cancer progression are badly needed. Methods: We conducted a copy number analysis to estimate amplification status of c-myc, cycD1 and EGFR oncogenes, mutational PCR-SSCP analysis to determine activation of H-ras oncogene and inactivation of TP53 tumour suppressor gene and methylation specific PCR analysis to evaluate hypermethylation of p16 and MGMT genes. Results: c-myc oncogene was amplified in 56.7%, cycD1 in 20% and EGFR in 16.7% of Oral Squamous Cell Carcinoma (OSCC) cases while H-ras was activated in 33.3% of samples. Amplification of c-myc was significantly associated with the tumour grade 2. Interestingly, EGFR and H-ras alterations were mutually exclusive. p16 and MGMT were inactivated by hypermethylation in 30% and 13.3% of cases. Co-alteration of cycD1 and p16 were not observed in any of the analyzed samples. TP53 was inactivated in 56.7% of samples and was significantly associated with progression of OSCC, grade 2 and stage 2. Moreover, TP53 and c-myc oncogene were simultaneously altered in grade 2 OSCC. Conclusions: The most promising marker of OSCC progression remains the TP53 tumour suppressor, which is the most frequently mutated gene in oral cancers. Since there is synergism between TP53 and c-myc, it seems that co-alteration of these two genes could be also a good marker of OSCC progression from grade1 to grade 2 tumours

Amplification of Cycline D1, C-Myc and Egfr Oncogenes in Tumour Samples of Breast Cancer Patients

Background: Breast cancer is the most common form of cancer in women. It arises from multiple genetic changes in oncogenes and tumor suppressor genes. Among so far studied oncogenes relatively few, including epdermal growth factor receptor (EGFR), cyclinD1 (CCND1) and c-myc, have been found to play an important role in progression of this type of human malignancy. The aim of this study was to examine the prognostic potential of CCND1, c-myc and EGFR amplification and their possible cooperation in breast carcinogenesis. Methods: Copy number analyses of CCND1 and c-myc genes were done by TaqMan based quantitative real time PCR. Amplification status of EGFR was determined by differential PCR. Results: Amplification of CCND1, c-myc and EGFR oncogene has been found in 20.4%, 26.5% and 26.5% of breast cancer cases, respectively. Analysis showed that amplification of CCND1 oncogene was significantly associated with the stage II of disease while amplification of EGFR gene was significantly associated with overexpression of HER-2/neu. Tumour stage and expression of HER-2/neu appeared to be significant predictors of patients outcome. Stage I patients lived significantly longer then stage III patients (p=0.04) while patients with HER-2/neu overexpression had worse prognoses and lived significantly shorter (p=0.001). Finally, survival of patients who underwent hormone therapy only was significantly longer (p=0.001) then survival of the rest of patients. Conclusions: Amplification of CCND1 or EGFR oncogene is associated with the progression of breast cancer and bad prognosis. No co-ordination in amplification of CCND1, c-myc and EGFR oncogenes were established in this cohort of breast cancer patients

Systematic bioinformatic analyses of nutrigenomic modifications by polyphenols associated with cardiometabolic health in humans: Evidence from targeted nutrigenomic studies

Cardiometabolic disorders are among the leading causes of mortality in the human population. Dietary polyphenols exert beneficial effects on cardiometabolic health in humans. Molecular mechanisms, however, are not completely understood. Aiming to conduct in-depth integrative bioinformatic analyses to elucidate molecular mechanisms underlying the protective effects of polyphenols on cardiometabolic health, we first conducted a systematic literature search to identify human intervention studies with polyphenols that demonstrate improvement of cardiometabolic risk factors in parallel with significant nutrigenomic effects. Applying the predefined inclusion criteria, we identified 58 differentially expressed genes at mRNA level and 5 miRNAs, analyzed in peripheral blood cells with RT-PCR methods. Subsequent integrative bioinformatic analyses demonstrated that polyphenols modulate genes that are mainly involved in the processes such as inflammation, lipid metabolism, and endothelial function. We also identified 37 transcription factors that are involved in the regulation of polyphenol modulated genes, including RELA/NFKB1, STAT1, JUN, or SIRT1. Integrative bioinformatic analysis of mRNA and miRNA-target pathways demonstrated several common enriched pathways that include MAPK signaling pathway, TNF signaling pathway, PI3K-Akt signaling pathway, focal adhesion, or PPAR signaling pathway. These bioinformatic analyses represent a valuable source of information for the identification of molecular mechanisms underlying the beneficial health effects of polyphenols and potential target genes for future nutrigenetic studies

Immunohistomorphometric Characteristics Of Pituitary GH Cells In Infant And Peripubertal Female Rats After Treatment With Estradiol Or Human Chorionic Gonadotropin

The effects of estradiol-dipropionate (EDP) or human chorionic gonadotropin (hCG) on immunohistomorphometric characteristics of pituitary GH cells in infant and peripubertal female rats were investigated. The first group of females received five injections of EDP (0.25 mg/kg b.w.) during the neonatal period of life, and was further divided into two subgroups which were sacrificed at the infantile period (17th day) or at the peripubertal period (38th day). The second group received two doses of hCG (50 IU/kg b.w.) on the 15th and 16th day of life in the first subgroup, and on the 36th and 37th days of life in the second subgroup, while they were sacrificed 24 h after the last treatment, respectively. The control females were injected with an equivalent volume of the vehicle and sacrificed according to the appropriate schedules as the hormone treated rats. EDP treatment decreased GH cell volume density in infant and peripubertal females, by 38% and 76% (p<0.05) respectively, in comparison with the controls. The number of GH cells per mm2 in infantile and peripubertal period was decreased in EDP treated animals by 26% and 53% (p<0.05) respectively, compared to the controls. Also, upon EDP treatment in both periods, GH cells were diminished in size and less intensely immunolabelled than in the control groups. The morphometric parameters in animals treated with hCG were insignificantly changed in both analyzed periods, in comparison with the controls. Unlike hCG, EDP manifested clear inhibitory effects on the immunohistomorphometric characteristics of GH cells in examined female rats

Diet-Induced Obesity and Ghrelin Effects on Pituitary Gonadotrophs: Immunohistomorphometric Study in Male Rats

Objective: The close relationship between energy metabolism, nutritional state, and reproductive physiology suggests that nutritional and metabolic disorders can disrupt normal reproductive function and fertility. Considering the importance of leptin and ghrelin effects in regulation of the hypothalamic-pituitary-gonadal axis, the objective of this study was to investigate the influence of obesity and centrally applied ghrelin on immunohistochemical appearance and quantitative morphology of the pituitary follicle-stimulating hormone (FSH) and luteinizing hormone (LH) producing cells in adult male rats. Materials and Methods: In this experimental study, animals were given two different diets: normal-fat (NF) and high-fat (HF), for 4 weeks, corresponding to normal and positive energy balance (n=2×14), respectively. Each group was subsequently divided into two subgroups (n=7) receiving intracerebroventricular (ICV) injections of either ghrelin [G, 1 μg/5 μL phosphate buffered saline (PBS)] or vehicle (5 μL PBS, control group) every 24 hours for five consecutive days. Results: Morphometric analyses showed that in HF control group, the percentage of FSH cells per unit volume of total pituitary gland tissue (in μm3), i.e. volume density (Vvc), was increased (P<0.05) by 9.1% in comparison with the NF controls. After ICV treatment with ghrelin, volume (Vc) and volume density (Vvc) of FSH cells in ghrelin+NF (GNF) and ghrelin+HF (GHF) groups remained unchanged in comparison with NF and HF controls. Volume of LH cells in HF control group was increased by 17% (P<0.05), but their Vvc was decreased by 8.3% (P<0.05) in comparison with NF controls. In GNF group, the volume of LH cells increased by 7% (P<0.05), in comparison with the NF controls, but in GHF group, the same parameter remained unchanged when compared with HF controls. The central application of ghrelin decreased the Vvc of LH cells only in GNF group by 38.9% (P<0.05) in comparison with the NF control animals. Conclusion: The present study has shown that obesity and repetitive ICV administration of low doses of ghrelin, in NF and HF rats, modulated the immunohistomorphometric features of gonadotrophs, indicating the importance of obesity and ghrelin in regulation of the reproductive function