Project description:The relationship between the TP53 Arg72Pro polymorphism (rs1042522) and the risk of leukemia remains controversial. Consequently, we performed a meta-analysis to accurately evaluate the association between TP53 Arg72Pro polymorphism and leukemia risk. A comprehensive search was conducted to find all eligible studies of TP53 Arg72Pro polymorphism and leukemia risk. Fourteen case-control studies, with 2,506 cases and 4,386 controls, were selected for analysis. The overall data failed to indicate a significant association between TP53 Arg72Pro polymorphism and the risk of leukemia (C vs. G: OR = 1.09, 95% CI = 0.93-1.26; CC vs. GC + GG: OR = 1.23, 95% CI = 0.96-1.57). In a subgroup analysis of clinical types, an increased risk was observed in the acute lymphocytic leukemia (ALL) subgroup (CC vs. GC + GG: OR = 1.73; 95% CI = 1.07-2.81) but not in the acute myeloid leukemia (AML) subgroup. In the subgroup analysis, no significant associations with ethnicity and the source of the controls were observed. In conclusion, the results suggest that there is no association between TP53 Arg72Pro polymorphism and the risk of leukemia, but the CC genotype may increase the risk of ALL TP53 Arg72Pro polymorphism CC genotype may increase the risk of ALL but is not associated with AML. Further large-scale, well-designed studies are needed to confirm our results.
Project description:The p53 tumor suppressor directs the cellular response to many mechanistically distinct DNA-damaging agents and is selected against during the pathogenesis of therapy-related acute myeloid leukemia (t-AML). We hypothesized that constitutional genetic variation in the p53 pathway would affect t-AML risk. Therefore, we tested associations between patients with t-AML (n = 171) and 2 common functional p53-pathway variants, the MDM2 SNP309 and the TP53 codon 72 polymorphism. Although neither polymorphism alone influenced the risk of t-AML, an interactive effect was detected such that MDM2 TT TP53 Arg/Arg double homozygotes, and individuals carrying both a MDM2 G allele and a TP53 Pro allele, were at increased risk of t-AML (P value for interaction is .009). This interactive effect was observed in patients previously treated with chemotherapy but not in patients treated with radiotherapy, and in patients with loss of chromosomes 5 and/or 7, acquired abnormalities associated with prior exposure to alkylator chemotherapy. In addition, there was a trend toward shorter latency to t-AML in MDM2 GG versus TT homozygotes in females but not in males, and in younger but not older patients. These data indicate that the MDM2 and TP53 variants interact to modulate responses to genotoxic therapy and are determinants of risk for t-AML.
Project description:The TP53 gene product is an important regulator of cell growth and a tumor suppressor. The association between TP53 Arg72Pro polymorphism and ovarian cancer risk has been widely investigated, but the results are contradictory. We therefore searched the PubMed, EMBASE and Chinese Biomedical databases for studies on the relation between TP53 Arg72Pro polymorphism and ovarian cancer risk. Our final meta-analysis included 24 published studies with 3271 cases and 6842 controls. Pooled results indicated that there was no significant association between TP53 Arg72Pro polymorphism and ovarian cancer risk [Pro/Pro vs. Arg/Arg: odds ratio (OR) =1.04, 95% confidence interval (CI) = 0.81-1.34; Arg/Pro vs. Arg/Arg: OR = 1.14, 95% CI = 0.96-1.36; recessive: OR = 1.05, 95% CI = 0.90-1.22; dominant: OR = 1.12, 95% CI = 0.94-1.33; and Pro vs. Arg: OR = 1.06, 95% CI=0.93-1.20]. Likewise, stratified analyses failed to reveal a genetic association. Despite some limitations, the present meta-analysis provides statistical evidence indicating a lack of association between TP53 Arg72Pro polymorphism and ovarian cancer risk.
Project description:BackgroundMany studies have reported that the p53 codon 72 polymorphism is associated with acute myeloid leukemia (AML) susceptibility; however, the conclusions are inconsistent. Therefore, we performed this meta-analysis to obtain a more precise result.Material and methodsWe searched PubMed to identify relevant studies, and 6 published case-control studies were retrieved, including 924 AML patients and 3832 controls. Odds ratio (OR) with corresponding 95% confidence interval (95%CI) was applied to assess the association between p53 codon 72 polymorphism and AML susceptibility. The meta-analysis was performed with Comprehensive Meta-Analysis software, version 2.2.ResultsOverall, no significant association between p53 codon 72 polymorphism and AML susceptibility was found in this meta-analysis (Pro vs. Arg: OR=0.94, 95%CI=0.81-1.10; Pro/Pro vs. Arg/Arg: OR=0.93, 95%CI=0.71-1.22; Arg/Pro vs. Arg/Arg: OR=0.79, 95%CI=0.55-1.13; (Pro/Pro + Arg/Pro) vs. Arg/Arg: OR=0.84, 95%CI=0.62-1.13; Pro/Pro vs. (Arg/Arg + Arg/Pro): OR=1.06, 95%CI=0.83-1.35). Similar results were also found in stratified analysis according to ethnicity and source of controls.ConclusionsOur meta-analysis demonstrates that p53 codon 72 polymorphism may not be a risk factor for AML, which should be verified in future studies.
Project description:Wilms' tumor is one of the most prevalent pediatric malignancies, ranking fourth in childhood cancer worldwide. TP53 is a critical tumor suppressor gene, which encodes a 53 kDa protein, p53. The p53 functions to protect against cancer by regulating cell cycle and apoptosis and maintaining DNA integrity. TP53 gene is highly polymorphic. Several TP53 gene polymorphisms have been considered to be associated with cancer risk. Of them, a nonsynonymous polymorphism, Arg72Pro (rs1042522 C>G), has been most extensively studied for the association with cancer risk; however, few studies have investigated its effect on Wilms' tumor. Because of the central role of p53 in cell cycle control, the TP53 gene Arg72Pro polymorphism is also a good potential candidate predisposition locus for this pediatric cancer. We genotyped this polymorphism in 145 patients and 531 cancer-free controls recruited from Chinese children by Taqman methodology. Overall, our result suggested a lack of association between the TP53 gene Arg72Pro polymorphism and Wilms' tumor. In the stratified analysis, we found that carriers of CG/GG genotypes had a significantly increased Wilms' tumor risk in children not older than 18 months (adjusted odds ratio =2.04, 95% confidence interval =1.003-4.13, P=0.049) compared with CC genotype carriers. Our study indicated that the TP53 gene Arg72Pro polymorphism may have a weak, age-related effect on Wilms' tumor risk in Chinese children. These findings need further validations in other populations with larger sample size.
Project description:Pediatric solid tumors are heterogeneous and comprise various histological subtypes. TP53, a tumor suppressor, orchestrates the transcriptional activation of anti-cancer genes. The gene coding for this protein is highly polymorphic, and its mutations are associated with cancer development. The Arg72Pro polymorphism in TP53 has been associated with susceptibility to various types of cancer. Here, in this hospital-based study, we evaluated the association of this polymorphism with susceptibility toward malignant abdominal solid tumors in children in the Hunan province of China. We enrolled 162 patients with neuroblastoma, 60 patients with Wilms' tumor, and 28 patients with hepatoblastoma as well as 270 controls. Genotypes were determined using a TaqMan assay, and the strength of the association was assessed using an odds ratio, within a 95% confidence interval identified using logistic regression models. Our results showed that the Arg72Pro polymorphism did not exhibit significant association with susceptibility toward pediatric malignant abdominal solid tumors. Stratification analysis revealed that this polymorphism exerts weak sex- and age-specific effects on Wilms' tumor and hepatoblastoma susceptibility, respectively. Overall, our results indicate that the Arg72Pro polymorphism may have a marginal effect on susceptibility toward pediatric malignant abdominal solid tumors in Hunan, and this finding warrants further confirmation.
Project description:BackgroundTP53 mutation (TP53mut ) confers an adverse prognosis in acute myeloid leukemia (AML). Venetoclax with hypomethylating agents is a current standard for older patients; however, recent reports suggest that TP53mut confers resistance to venetoclax. The authors investigated the outcomes of patients with TP53mut AML who were treated with a 10-day decitabine and venetoclax (DEC10-VEN) (ClinicalTrials.gov identifier NCT03404193).MethodsPatients with newly diagnosed AML received decitabine 20 mg/m2 for 10 days every 4 to 6 weeks for induction, followed by decitabine for 5 days after response. The venetoclax dose was 400 mg daily. TP53mut was identified in bone marrow samples using next-generation sequencing, with sensitivity of 5%. Outcomes were analyzed according to European LeukemiaNet 2017 guidelines.ResultsAmong 118 patients (median age, 72 years; age range, 49-89 years), 63 (53%) had secondary AML, 39 (33%) had AML with complex karyotype, and 35 (30%) had TP53mut AML. The median TP53 variant allele frequency was 32% (interquartile range, 16%-65%), 8 patients (23%) had only a single TP53 mutation, 15 (43%) had multiple mutations, and 12 (34%) had mutation and deletion. Outcomes were significantly worse in patients who had TP53mut AML compared with those who had wild-type TP53 AML, with an overall response rate of 66% vs 89% (P = .002), a complete response/complete response with incomplete hematologic recovery rate of 57% vs 77% (P = .029), and a 60-day mortality of 26% vs 4% (P < .001), respectively. Patients with TP53mut versus wild-type TP53 had shorter overall survival at 5.2 versus 19.4 months, respectively (hazard ratio, 4.67; 95% CI, 2.44-8.93; P < .0001), and shorter relapse-free survival at 3.4 versus 18.9 months (hazard ratio, 4.80; 95% CI, 1.97-11.69; P < .0001), respectively. Outcomes with DEC10-VEN in patients with TP53mut AML were comparable to historical results with 10-day decitabine alone.ConclusionsPatients with TP53mut AML have lower response rates and shorter survival with DEC10-VEN.
Project description:Several previous studies evaluated the association between the Arg72Pro (rs1042522) polymorphism in the TP53 tumor suppressor gene and colorectal cancer (CRC). However, the results are conflicting. This meta-analysis aimed to shed new light on the precise association between TP53 variants and CRC. We analyzed 32 published case-control studies involving 8,586 cases and 10,275 controls using crude odd ratios (ORs) with 95% confidence intervals (CIs). The meta-analysis was performed using a fixed-effect or random-effects model, as appropriate. We found that the TP53 Arg72Pro polymorphism was not significantly associated with CRC risk in the overall population. However, subgroup analysis based on ethnicity revealed an increased risk of CRC among Asians (CC vs. GC+GG: OR=1.22, 95% CI: 1.02-1.45), and similar results were found for rectal cancer (CC vs. GC+GG: OR=1.34, 95% CI: 1.120-1.62). These results suggest that the TP53 Arg72Pro polymorphism CC genotype may contribute to an increased risk of CRC, especially for rectal cancer and among Asians.
Project description:TP53 is a key tumor suppressor gene that plays an important role in regulating apoptosis, senescence, and DNA damage repair in response to cellular stress. Although somewhat rare, TP53-mutated AML has been identified as an important molecular subgroup with a prognosis that is arguably the worst of any. Survival beyond one year is rare after induction chemotherapy with or without consolidative allogeneic stem cell transplant. Although response rates have been improved with hypomethylating agents, outcomes remain particularly poor due to short response duration. Improvements in our understanding of AML genetics and biology have led to a surge in novel treatment options, though the clinical applicability of these agents in TP53-mutated disease remains largely unknown. This review will focus on the epidemiology, molecular characteristics, and clinical significance of TP53 mutations in AML as well as emerging treatment options that are currently being studied.
Project description:The role of subclonal TP53 mutations, defined by a variant allele frequency of <20%, has not been addressed in acute myeloid leukemia yet. We, therefore, analyzed their prognostic value in a cohort of 1,537 patients with newly diagnosed disease, prospectively treated within three trials of the "German-Austrian Acute Myeloid Leukemia Study Group". Mutational analysis was performed by targeted deep sequencing and patients with TP53 mutations were categorized by their variant allele frequency into groups with frequencies >40%, 20%-40% and <20%. A total of 108 TP53 mutations were found in 98 patients (6.4%). Among these, 61 patients had variant allele frequencies >40%, 19 had variant allele frequencies between 20%-40% and 18 had frequencies <20%. Compared to specimens with clonal TP53 mutations, those with subclonal ones showed significantly fewer complex karyotypes and chromosomal losses. In either TP53-mutated group, patients experienced significantly fewer complete responses (P<0.001) and had worse overall and event-free survival rates (P<0.0001). In Cox regression analyses adjusting for age, white blood cell count, cytogenetic risk and type of acute myeloid leukemia, the adverse prognostic effect of TP53 mutations remained significant for all TP53-mutated subgroups. These data suggest that subclonal TP53 mutations are a novel prognostic parameter in acute myeloid leukemia and emphasize the usefulness of next-generation sequencing technologies for risk stratification in this disorder. The study was registered at ClinicalTrials.gov with number NCT00146120.