Body mass index (BMI) and mutations of tumor suppressor gene p53 (TP53) in patients with urinary bladder cancer

The potential diagnosis role of TP53 mutation in advanced bladder cancer: A meta-analysis

BACKGROUND

Bladder cancer is one of the most common urological cancers all over the world, and NMIBC occupies almost 80% of recently diagnosed bladder cancer cases. Progress and recurrence of bladder cancer are the main problems during the disease. The level of TP53 mutation is obviously higher in the high stage than the lower. This meta-analysis is to evaluate the potential diagnosis feature of TP53 mutation by the expression of TP53 mutation of Ta stage vs high stage in bladder cancer.

METHODS

A systematic search of databases was conducted, and some relevant articles were selected. Next, the meta-analysis was carried out according to the standard guidelines.

RESULTS

There were seven researches in which 677 participants were selected at the basis of inclusion standard. TP53 mutation was associated highly with increased diagnosis of bladder cancer. We found that the high stage of bladder cancer has obviously higher level of TP53 mutation than the lower stage, and these patients of MIBC have higher expression of TP53 mutation compared with NMIBC. No significant publication bias has been observed in this meta-analysis. The expression of TP53 mutation might be a diagnose-related biomarker for lots of patients with bladder cancer.

CONCLUSIONS

The results of this meta-analysis provided further evidences that the expression of TP53 mutation was associated with the diagnosis efficiency of advanced bladder cancer. Higher expression of TP53 mutation was observed in the high stage of bladder cancer or the MIBC, and lower expression of TP53 mutation in the Ta stage of bladder cancer or the NMIBC. The expression level of TP53 mutation was probably a critical diagnosed biomarker in advanced bladder cancer.

Impact of obesity and overweight on DNA stability: Few facts and many hypotheses

Health authorities are alarmed worldwide about the increase of obesity and overweight in the last decades which lead to adverse health effects including inflammation, cancer, accelerated aging and infertility. We evaluated the state of knowledge concerning the impact of elevated body mass on genomic instability. Results of investigations with humans (39 studies) in which DNA damage was monitored in lymphocytes and sperm cells, are conflicting and probably as a consequence of heterogeneous study designs and confounding factors (e.g. uncontrolled intake of vitamins and minerals and consumption of different food types). Results of animal studies with defined diets (23 studies) are more consistent and show that excess body fat causes DNA damage in multiple organs including brain, liver, colon and testes. Different molecular mechanisms may cause genetic instability in overweight/obese individuals. ROS formation and lipid peroxidation were found in several investigations and may be caused by increased insulin, fatty acid and glucose levels or indirectly via inflammation. Also reduced DNA repair and formation of advanced glycation end products may play a role but more data are required to draw firm conclusions. Reduction of telomere lengths and hormonal imbalances are characteristic for overweight/obesity but the former effects are delayed and moderate and hormonal effects were not investigated in regard to genomic instability in obese individuals. Increased BMI values affect also the activities of drug metabolizing enzymes which activate/detoxify genotoxic carcinogens, but no studies concerning the impact of these alterations of DNA damage in obese individuals are available. Overall, the knowledge concerning the impact of increased body weight and DNA damage is poor and further research is warranted to shed light on this important issue.

Adiposity is associated with p53 gene mutations in breast cancer

Mutations in the p53 gene are among the most frequent genetic events in human cancer and may be triggered by environmental and occupational exposures. We examined the association of clinical and pathological characteristics of breast tumors and breast cancer risk factors according to the prevalence and type of p53 mutations. Using tumor blocks from incident cases from a case-control study in western New York, we screened for p53 mutations in exons 2-11 using the Affymetrix p53 Gene Chip array and analyzed case-case comparisons using logistic regression. The p53 mutation frequency among cases was 28.1 %; 95 % were point mutations (13 % of which were silent) and the remainder were single base pair deletions. Sixty seven percent of all point mutations were transitions; 24 % of them are G:C>A:T at CpG sites. Positive p53 mutation status was associated with poorer differentiation (OR, 95 % CI 2.29, 1.21-4.32), higher nuclear grade (OR, 95 % CI 1.99, 1.22-3.25), and increased Ki-67 status (OR, 95 % CI 1.81, 1.10-2.98). Cases with P53 mutations were more likely to have a combined ER-positive and PR-negative status (OR, 95 % CI 1.65, 1.01-2.71), and a combined ER-negative and PR-negative status (OR, 95 % CI 2.18, 1.47-3.23). Body mass index >30 kg/m(2), waist circumference >79 cm, and waist-to-hip ratio >0.86 were also associated with p53 status; obese breast cancer cases are more likely to have p53 mutations (OR, 95 % CI 1.78, 1.19-2.68). We confirmed that p53 mutations are associated with less favorable tumor characteristics and identified an association of p53 mutation status and adiposity.

MMP, VEGF and TIMP as prognostic factors in recurring bladder cancer

OBJECTIVES

To investigate the clinical correlates and prognostic utility of MMP, VEGF and TIMP genes expression in bladder cancer (BCa) recurrence.

METHODS

Expression of MMP1, MMP2, MMP9, VEGFA and TIMP1, TIMP3 was analyzed by qRT-PCR using SYBR Green in peripheral blood leukocytes (PBLs) of BCa patients at two time points (diagnosis (n=40), and first recurrence (n=40)) and an age-matched group of healthy controls (n=100). Plasma concentrations of MMP1 (pro- and active forms) were measured using ELISA in BCa patients.

RESULTS

The expression of MMP1 mRNA was significantly lower in BCa patients with first recurrence compared to control (p=0.019). Expression of other genes did not differ significantly between the groups. MMP9 gene expression was associated with differentiation grade (p=0.043), with the highest expression in poorly differentiated tumors (G3) and was higher in smokers than in non-smokers (p=0.039) in BCa patients at diagnosis. The results at two time points showed that MMP9 and VEGFA genes expression was increased in patients with moderately differentiated BCa (p=0.029), and advanced pathologic stage (p=0.048), respectively. Moreover, gene expression of TIMP1 was increased for G3 (p=0.043), and was decreased for early recurrence (p=0.003).

CONCLUSIONS

Our study suggests that the expression of MMP9 in PBLs of BCa patients at diagnosis is associated with the differentiation grade of the BCa, and smoking status. Genes expression of MMP9, VEGFA and TIMP1 in PBLs may play a pivotal role in regulation of progression of BCa. Additionally, TIMP1 gene expression may be important factor for early recurrence of BCa.

The impact of nutrition in urogenital cancers

Prostate, bladder and kidney cancers remain the most common cancers of the urinary tract. Despite improved primary prevention, detection and treatment, the incidence of age-related cancers of the urinary tract is likely to rise as a result of global population ageing. An association of diet with prostate, bladder and kidney carcinogenesis is plausible since the majority of metabolites, including carcinogens, are excreted through the urinary tract. Moreover, large regional differences in incidence rates of urologic tumours exist throughout the world. These rates change when people relocate to different geographic areas, which is suggestive of a strong environmental influence. As a result of these observations, numerous studies have been conducted to assess the effects of diet and nutritional status in kidney, bladder and prostate carcinogenesis. Here, we review the literature assessing the effect of diet and nutritional status on urological cancer risk, which has attracted the most interest.

TP53 intronic mutations in bovine enzootic hematuria-associated urinary bladder tumors

Tumor protein 53 (TP53) is a tumor suppressor gene that is frequently mutated in urinary bladder tumors in both humans and animals. In cattle, urinary bladder tumors have been reported as occurring spontaneously as well as in conjunction with bracken fern consumption-induced bovine enzootic hematuria (BEH). The goal of this study was to evaluate various types of bovine urinary bladder neoplasms for the presence of TP53 alterations, using the polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) method. DNA was extracted from both epithelial and mesenchymal urinary bladder tumor samples in cattle, associated with the chronic consumption of bracken fern. PCR was performed using primers targeted to exons 5 to 8, following electrophoresis and isolation, and the products were assessed by SSCP. Tumors in which alterations in the electrophoresis patterns were noted included hemangiomas, papillomas, and carcinomas in situ. Exemplars of these tumor types were selected for sequencing, and although no changes were noted in the 5 to 8 exon range, on either side of the designed primers for exon 6, there was some portion of intron 6 in which sequencing demonstrated a deletion of the thyamine nucleotide at position 9332. In summary, although mutations were not observed within exons 5 to 8, this represents the first report of an intronic mutation in the TP53 gene in association with bovine urinary bladder tumors. Mutations within introns can predispose tissues to the development of cancer, and therefore, a possible association between mutations of the introns of TP53 and the development of urinary bladder tumors in cattle with BEH should be further investigated.