MDM2 Rs2279744 Research Articles

Genetic variability profiling of the p53 signaling pathway in chronic lymphocytic leukemia. Individual and combined analysis of TP53, MDM2 and NQO1 gene variants.

TP53 gene disruption, including 17p13 deletion [del(17p)] and/or TP53 mutations, is a negative prognostic biomarker in chronic lymphocytic leukemia (CLL) associated with disease progression, treatment failure and shorter survival. Germline variants in p53 signaling pathway genes could also lead to p53 dysfunction, but their involvement in CLL has not been thoroughly evaluated. The aim of this study was to determine the association of TP53, MDM2 and NQO1 gene variability with clinical and genetic data of CLL patients. Individual genotype and haplotype data of CLL patients were compared with clinical prognostic factors, cytogenetic and molecular cytogenetic findings as well as IGHV and TP53 mutational status. The study included 116 CLL patients and 161 healthy blood donors. TP53 (rs1042522, rs59758982, rs1625895), NQO1 (rs1800566) and MDM2 (rs2279744, rs150550023) variants were genotyped using different PCR approaches. Analysis of genotype frequencies revealed no association with the risk of CLL. TP53 rs1042522, rs1625895 and MDM2 rs2279744 variants were significantly associated with abnormal karyotype and the presence of del(17p). Similarly, these two TP53 variants were associated with TP53 disruption. Moreover, TP53 C-A-nondel and G-A-del haplotypes (rs1042522-rs1625895-rs59758982) were associated with an increased likelihood of carrying del(17p) and TP53 disruptions. MDM2 T-nondel haplotype (rs2279744-rs150550023) was found to be a low risk factor for del(17p) (OR = 0.32; CI: 0.12-0.82; p = 0.02) and TP53 disruptions (OR = 0.41; CI: 0.18-0.95; p = 0.04). Our findings suggest that TP53 and MDM2 variants may modulate the risk to have chromosome alterations and TP53 disruptions, particularly del(17p). To our knowledge this is the first study of several germline variants in p53 pathway genes in Argentine patients with CLL.

Association of TP53 rs1042522 G > C, MDM2 rs2279744 T > G, and miR-34b/c rs4938723 T > C polymorphisms with aneuploidy pregnancy susceptibility

BackgroundAneuploidy pregnancy is a severe major birth defect and causes about 50% spontaneous miscarriages with unknown etiology. To date, only a few epidemiological studies with small sample sizes have investigated the risk factors for aneuploidy pregnancy. TP53, MDM2, and miR-34b/c genes are implicated in tumorigenesis with aneuploidy, yet the function of their polymorphisms in aneuploidy pregnancy susceptibility needs to be clarified.ObjectiveTo elucidate the association of TP53 rs1042522 G > C, MDM2 rs2279744 309 T > G, and miR-34b/c rs4938723 T > C specific polymorphisms with aneuploidy pregnancy.MethodsIn the retrospective case-control study, 330 aneuploidies pregnancy women and 813 normal pregnancy controls were recruited between January 2018 and April 2022 at the First People’s Hospital of Yunnan Province, Kunming, China. Three functional polymorphisms, the TP53 rs1042522 G > C (Arg72Pro), MDM2 rs2279744 309 T > G, and miR-34b/c rs4938723 T > C, were genotyped using the snapshot method.ResultsThe frequency distribution of three genotypic variants was not different between case and control pregnant women and was similar to with Hardy-Weinberg Equilibrium (HWE). However, in the younger subgroup (less than 35 years old), a significant difference was detected in allele and recessive model (p = 0.01). In the advanced age subgroup (more than or equal to 35 years old), G of MDM2 rs2279744 T > G revealed a significantly higher frequency in cases than controls (p = 0.045), and miR-34b/c rs4938723 T > C revealed a significant difference under the dominant model (p = 0.03), but no significant differences were observed in other models and in both younger and older subgroup (p > 0.05, respectively). These results suggest that individual polymorphisms were not associated with aneuploidy pregnancy, combined with age, they may serve as a risk factor for aneuploidy pregnancy.ConclusionCombination of TP53 rs1042522 G > C, MDM2 rs2279744 T > G, and miR-34b/c rs4938723 T > C polymorphisms with maternal age may be related to aneuploidy pregnancy susceptibility. These findings might elaborate on the genetic etiology of aneuploidy pregnancy.

Meta-Analysis of 49 SNPs Covering 25,446 Cases and 41,106 Controls Identifies Polymorphisms in Hormone Regulation and DNA Repair Genes Associated with Increased Endometrial Cancer Risk.

Endometrial cancer (EC) is among the most common gynecological disorders globally. As single nucleotide polymorphisms (SNPs) play an important role in the causation of EC, therefore, a comprehensive meta-analysis of 49 SNPs covering 25,446 cases and 41,106 controls was performed to identify SNPs significantly associated with increased EC risk. PubMed was searched to identify case control studies and meta-analysis was performed to compute the pooled odds ratio (OR) at 95% confidence interval (CI). Cochran's Q-test and I2 were used to study heterogeneity, based on which either a random or a fixed effect model was implemented. The meta-analysis identified 11 SNPs (from 10 genes) to be significantly associated with increased EC risk. Among these, seven SNPs were significant in at least three of the five genetic models, as well as three of the polymorphisms (rs1801320, rs11224561, and rs2279744) corresponding to RAD51, PGR, and MDM2 genes, which contained more than 1000 EC cases each and exhibited increased risk. The current meta-analysis indicates that polymorphisms associated with various hormone related genes-SULT1A1 (rs1042028), PGR (rs11224561), and CYP19A1 (rs10046 and rs4775936); DNA repair genes-ERCC2 (rs1799793), OGG1 (rs1052133), MLH1 (rs1800734), and RAD51 (rs1801320) as well as genes like MDM2 (rs2279744), CCND1 (rs9344), and SERPINE1 (rs1799889), are significantly associated with increased EC risk.

Association Between Single Nucleotide Polymorphisms of Apoptosis and Cell Cycle Control Genes and the Risk of Cancer Development in Chronically Exposed Persons

The objective of the paper was to study the association between single nucleotide polymorphisms of genes involved in the cell cycle control (ATM rs664677, MDM2 rs2279744, CDKN1A rs1801270) and apoptosis (BCL-2 rs2279115, BAX rs4645878, TNFα rs361525) and the risk of solid cancer development in persons of different ethnicity exposed to chronic radiation. The study included 915 residents of the Techa riverside settlements belonging to two ethnic groups (Slavs and Turks) who were affected by chronic low dose rate exposure in the low to and medium dose range. 310 persons out of them had solid cancers. Genotyping of polymorphic regions of genes regulating cell cycle and apoptosis was performed by real-time PCR method. The study showed that the rs2279744*C allele of the MDM2 gene was associated with an increased risk of cancer development (OR = 2.29; 95% CI 1.23–4.28; p = 0.007), while the rs1801270*A allele of the CDKN1A gene showed a protective effect against cancer development (OR = 0.55; 95% CI 0.35–0.85; p = 0.01) in exposed individuals of the Turkic ethnic group. The combined effect of the identified polymorphisms and soft tissue exposure dose statistically significantly modifies the risk of cancer development in chronically exposed persons of the Turkic ethnic group, with the greatest contribution being made by the carriage of the rs2279744*C allele of the MDM2 gene.

Alterations in p53 Influence hTERT, VEGF and MMPs Expression in Oral Cancer Patients.

Mutant p53 is the crucial molecule in the etiopathogenesis of oral cancer. Therefore, we aimed to evaluate the impact of alterations of the p53 gene and its negative feedback regulator, MDM2, on the expression of hTERT, VEGF, and MMPs; the critical genes involved in oral cancer progression. p53 and MDM2 genotyping were done by PCR-RFLP. p53 mutation analysis was performed using PCR-SSCP and sequencing. hTERT, VEGFA isoforms, MMP2, and MMP9 mRNA levels were analyzed by semi-quantitative Reverse Transcriptase PCR. Arg allele at p53 exon 4 was significantly associated with overexpression of hTERT, MMP2, and MMP9 individually. Expression of hTERT, VEGF A isoforms, MMP2 and MMP9 were significantly altered in the presence of p53 and MDM2 polymorphisms and p53 mutations in a specific combination. Mutant p53, Arg allele at p53 exon 4 locus, and G/G/or T/T genotype at MDM2revealed increased expression of hTERT, VEGF A isoforms, and MMP2/9. This study provides evidence that apart from mutant p53, naturally occurring sequence variants in p53codon 72 (Arg72Pro) (rs1042522) and MDM2 (rs2279744) significantly alter the expression of hTERT, VEGF-A isoforms, and MMP2/9 in a specific combination. The differential interaction of codon 72 variants with MDM2, hTERT, VEGF-A isoforms and MMP2/9 play a role in the aggressiveness of oral cancer. The results have important implications for oral cancer progression and should be explored for innovative treatment options.

Association between ТР53, MDM2 and NQO1 gene polymorphisms and viral load among women with human papillomavirus.

The risk of cervical cancer is caused by persistent human papillomavirus (HPV) infection. Cervical cancer is the most frequent cancer among women. Our purpose was to investigate the association between TP53 215C>G (Pro72Arg), MDM2 -410T>G, and NQO1 609C>T gene polymorphisms with a high HPV load and the inf luence of gene-gene interactions on prolonged HPV infection. Eighty-nine women with a high HPV viral load and 114 healthy women were involved in a case–control study. Genotyping for TP53 215C>G (Pro72Arg) and MDM2 -410T>G SNPs was carried out by allele-specif ic PCR and genotyping for NQO1 609C>T was performed by a TaqMan assay. Quantitative analysis of HPV DNA was performed by AmpliSens® HPV HCR screen-titer-FRT test system. Gene-gene interactions were analyzed using the multifactor dimensionality reduction (MDR) method. The study of separate SNPs of MDM2 -410T>G and NQO1 609C>T genes did not reveal any statistically signif icant difference in genotype and allele frequencies among women within the two groups. The frequency of the 215G (72Arg) allele and 215GG (72Arg/ Arg) genotype of the TP53 gene was signif icantly higher in the case group than in the control group (OR = 1.74, 95 % CI = 1.10–2.73; p = 0.02 and OR = 1.97, 95 % CI = 1.13–3.46; p = 0.04, respectively). MDR analysis showed the signif icance of intergenic interactions of the three studied loci TP53 (rs1042522) – MDM2 (rs2279744) – NQO1 (rs1800566) for the formation of a high HPV load (OR = 3.05, 95 % CI = 1.73–5.46; p = 0.0001).

The importance of assessing nucleotide polymorphisms of the <i>tp53</i> signaling pathway genes in uterine infertility factor diagnosis

INTRODUCTION: The WHO reported a 30% frequency of female infertility, which does not tend to decrease. Concurrently, the uterine factor occupies one of the most important places in infertility structure, reaching 50%. Improvement of assisted reproductive technology methods can successfully overcome many causes of infertility, but the possibilities of the method are limited in the uterine factor of infertility.
 AIM: To assess the presence of nucleotide polymorphisms of the TP53 signaling pathway genes (LIF rs41281637, c.256GA; LIF rs929271, n.397-2854TG; MDM2 rs2279744, c.14+309TG; MDM4 rs1563828, c.558+572AG; TP53 rs1042522, c.215CG) in the endometrium in patients with primary and secondary infertility.
 MATERIALS AND METHODS: In 20182021, the V.F. Snegirev Clinic of Obstetrics and Gynecology examined and treated 54 patients aged 26 to 48 years with primary or secondary infertility, including a genetic endometrial sample examination. The first group consisted of 28 patients with primary infertility aged 26 to 42 years. The 2nd group included 26 patients aged 29 to 48 years with secondary infertility.
 RESULTS: The study evaluated the expression of nucleotide polymorphisms of the TP53 signaling pathway genes in patients with primary and secondary infertility. Study results, data were obtained indicating various variants of nucleotide polymorphisms LIF, MDM2, MDM4, and TP53 in primary and secondary infertility, as well as the identity of a marker, such as LIF rs41281637 (G/A) in patients of both groups.
 CONCLUSION: The experimental data obtained indicate an important contribution of genetic polymorphisms in the genes of the TP53, LIF and MDM4 signaling pathway to the development of primary and MDM2 secondary infertility in women.

Five MDM4 gene polymorphisms on cancer risk: An updated systematic review and meta-analysis.

The study aims to provide a comprehensive account of the association of five MDM4 gene polymorphisms (rs1380576, rs1563828, rs10900598, rs11801299, and rs4245739) with susceptibility to cancer. A literature search for eligible candidate gene studies published before 27 February 2021 was conducted in PubMed, Medline and Web of Science. The following combinations of main keywords were used: (MDM4 OR MDMX OR HDMX OR mouse double minute 4 homolog) AND (polymorphism OR mutation OR variation OR SNP OR genotype) AND (cancer OR tumor OR neoplasm OR malignancy OR carcinoma OR adenocarcinoma). Potential sources of heterogeneity were sought out via meta-regression, subgroup and sensitivity analysis. Overall, a total of 15 articles with 21,365 cases and 29,280 controls for five polymorphisms of the MDM4 gene were enrolled. In the stratified analysis of rs1380576, we found that Asians might have less susceptibility to cancer. We found that rs4245739 was correlated with a decreased risk of cancer for Asians and breast cancer susceptibility. However, for other polymorphisms, the results showed no significant association with cancer risk. MDM4 rs1380576 polymorphism is negatively associated with the risk of cancer in the Asian population. MDM4 rs4245739 polymorphism is inversely associated with cancer risk for Asians and breast cancer susceptibility.

Associations of MDM2 and MDM4 Polymorphisms with Early-Stage Breast Cancer.

Breast cancer is one of the most common cancers worldwide. Single nucleotide polymorphisms (SNPs) in MDM2 and MDM4 have been associated with various cancers. However, the influence on clinical characteristics of breast cancer has not been sufficiently investigated yet. Thus, this study aimed to investigate the relationship between SNPs in MDM2 (rs2279744, rs937283, rs937282) and MDM4 (rs1380576, rs4245739) and I–II stage breast cancer. For analysis, the genomic DNA was extracted from 100 unrelated women peripheral blood. Polymorphisms were analyzed with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. The study showed that MDM2 rs937283 and rs937282 were significantly associated with estrogen receptor status and human epidermal growth factor receptor 2 (HER2) status. SNPs rs1380576 and rs4245739, located in MDM4, were significantly associated with status of estrogen and progesterone receptors. Our findings suggest that rs937283 AG, rs937282 CG, rs1380576 CC, and rs4245739 AA genotypes were linked to hormonal receptor positive breast cancer and may be useful genetic markers for disease assessment.

The cell cycle regulatory gene polymorphisms TP53 (rs1042522) and MDM2 (rs2279744) in lung cancer: a meta-analysis.

Lung cancer is one of the most common types of cancer in the world. Although the mechanism of lung cancer is still unknown, a large number of studies have found a link between gene polymorphisms and the risk of lung cancer. The tumor suppressor p53 plays a crucial role in maintaining genomic stability and tumor prevention. MDM2 is a critical regulator of the p53 protein. Despite the importance of p53 pathway in cancer, data on the contribution of SNPs of TP53 (rs1042522) and MDM2 (rs2279744) to the development of lung cancer are very contradictory. A metaanalysis that collects quantitative data from individual studies and combines their results has the advantage of improving accuracy, providing reliable estimates, and resolving those issues in which studies on individual associations are not effective enough. The aim of this study was to determine whether the TP53 (rs1042522) and MDM2 (rs2279744) polymorphisms confer susceptibility to lung cancer. A meta-analysis was conducted on the associations between the TP53 (rs1042522) and MDM2 (rs2279744) polymorphisms and lung cancer. A total of 51 comparison studies including 25,366 patients and 25,239 controls were considered in this meta-analysis. The meta-analysis showed no association between lung cancer and MDM2 (rs2279744) under any model. A noteworthy association of TP53 (rs1042522) with susceptibility to lung cancer in overall pooled subjects was observed under three different models (allele contrast, homozygote contrast (additive) and dominant). Stratification by ethnicity indicated an association between the TP53 (rs1042522) and lung cancer in Asians and Caucasians. This meta-analysis demonstrates that the TP53 (rs1042522), but not MDM2 (rs2279744) polymorphism may confer susceptibility to lung cancer.

Association of MDM4 Gene rs4245739 Polymorphism with the Risk and Clinical Characteristics of Colorectal Cancer in a Chinese Han Population.

BackgroundStudies show that MDM4 may play a pivotal role in colorectal cancer (CRC). Recently, a host of studies suggest that MDM4 gene rs4245739 polymorphism may modify the risk of different cancers.MethodsIn this study, we were interested whether MDM4 gene rs4245739 polymorphism correlated with the risk and clinical characteristics of CRC. Logistic regression was adopted to estimate the association of rs4245739 polymorphism and CRC risk.ResultsWe enrolled 444 CRC patients and 530 controls and found MDM4 gene rs4245739 polymorphism may decrease the risk of CRC. Stratified analyses uncovered that this variant was connected to a less risk of CRC in females, non-drinkers, non-smokers, and people under 60 years old. Additionally, rs4245739 polymorphism was related to TNM staging, pathological type, tumor size, and location of CRC. Furthermore, this polymorphism was significantly linked with the survival of CRC.ConclusionTotally, this study suggests that MDM4 rs4245739 polymorphism is linked with the risk and clinical characteristics of CRC.

Correlation between P53 Arg72Pro and MDM4 gene rs4245739 polymorphisms in breast cancer

BackgroundMDM4 is a negative regulator of p53 tumor suppression pathway. Various studies reveal the fact that the rs4245739A>C polymorphism of MDM4 in 3′-untranslated region is targeted by miR-191 which leads to lower MDM4 expression. On the other hand, the importance of Arg72Pro polymorphism of p53 in breast cancer is proven. The aim of this study is to present the correlation between the aforementioned SNPs and the risk of breast cancer. The statistical society of the study includes 199 healthy women as the control group and 206 women suffering from breast cancer included from Turkish population of the East Azarbaijan. ResultsAlleles of both positions are detected through Tetra-ARMS PCR while SPSS and the SHEsis, online software was exerted for allele typing, genotyping, and haplotype analysis. Different alleles of both MDM4 rs4245739 and p53 Arg72Pro had no significant frequency in patients (P > 0.05). Furthermore, genotypes of neither MDM4 rs4245739 nor p53 Arg72Pro could increase or decrease the risk of breast cancer in patients compared to healthy women. Additionally, a significant factor affecting the risk of breast cancer is gene-gene interaction. The results of the ongoing study revealed that two genetic variants, MDM4 rs4245739 and p53 Arg72Pro polymorphisms, failed to be associated, individually and combined together, with the risk of breast cancer. However, additional well-designed studies on large populations are required to validate such an association. ConclusionVarious alleles of both SNPs had no significant frequency difference between patients and controls. Moreover, genotypes of neither MDM4 nor p53 were significantly distributed in women with breast cancer compared to the healthy controls. Meanwhile, haplotype analysis failed to be significant. Last but not least, all clinical manifestations, other than association between tumor size and MDM4 genotypes could not be correlated with either various alleles or genotypes.

Association Analysis of TP53 rs1042522, MDM2 rs2279744, rs3730485, MDM4 rs4245739 Variants and Acute Myeloid Leukemia Susceptibility, Risk Stratification Scores, and Clinical Features: An Exploratory Study.

This study aimed to explore the associations between the TP53 rs1042522 (TP53 Arg72Pro), MDM2 rs2279744 (MDM2 309T>G), rs3730485 (MDM2 del1518), MDM4 rs4245739 (MDM4 34091 C>A) variants and odds of developing acute myeloid leukemia (AML) in a cohort of 809 adult subjects, consisting of 406 healthy controls and 403 AML patients. Model-based multifactor dimensionality reduction (MB-MDR) framework was used to identify the interactions of the mentioned variants and their association with AML risk. Associations of the mentioned variants with clinical features of AML, somatic mutations, and response to treatment were also evaluated. Significant associations between TP53 rs1042522 and MDM4 rs4245739 variants and AML susceptibility were noticed. MB-MDR and logistic regression analysis revealed an interaction between MDM2 rs2279744 and TP53 rs1042522, between MDM4 rs4245739 and MDM2 rs3730485, as well as significant associations with AML susceptibility. Several associations between the mentioned variants and clinical features of AML and somatic mutations were also noticed. Individually, the variant genotypes of TP53 rs1042522 and MDM4 rs4245739 were associated with AML susceptibility, but their interaction with MDM2 rs2279744 and rs3730485 modulated the risk for AML. The variant genotypes of TP53 rs1042522 were associated with adverse molecular and cytogenetic risk and also with NPM1 mutations.

Interactions among variants in P53 apoptotic pathway genes are associated with neurologic deterioration and functional outcome after acute ischemic stroke

ObjectiveNeurologic deterioration (ND) and functional outcome after ischemic stroke (IS) are not accurately predicted by clinical pictures on admission. The aim of present study was to investigate the association of variants in P53 apoptotic pathway genes with ND and functional outcome after IS.MethodsGenotypes of nine variants in apoptosis‐relevant genes were measured in patients with acute IS. Gene–gene interactions were analyzed by generalized multifactor dimensionality reduction (GMDR). The primary outcome was ND. ND was diagnosed in patients who worsened ≥2 points (National Institutes of Health Stroke Scale [NIHSS] score) within the first 10 days of stroke onset. The secondary outcome was functional status at 90 days after IS as measured by modified Rankin Scale (mRS) score.ResultsA total of 705 enrolled patients, ND occurred in 174 (24.7%) patients, and 184 (26.1%) patients were poor functional outcome (mRS score > 2). Although the nine variants were not significantly associated with ND and functional outcome by univariate analysis, there was a gene–gene interaction among P53rs1042522, MDM‐2rs2279744, and MMP‐9 rs3918242 using GMDR analysis. The high‐risk interaction among the three variants was independently associated with higher risk of ND (HR, 2.04, 95% CI: 1.22–5.64, p = .018) and poor functional outcome (OR, 2.68, 95% CI: 1.68–7.86, p = .004) after adjusting for the covariates.ConclusionThe interactions among P53 rs1042522, MDM‐2 rs2279744, and MMP‐9 rs3918242 may increase the risk of ND and poor functional outcome and may be considered as a genetic marker of predicting ND and poor functional outcome after stroke.

Long telomeres cooperate with p53, MDM2, and p21 polymorphisms to raise pediatric solid tumor risk.

While leukocyte telomere length has been linked with altered risk in adult cancer, limited information is available on its association with risk in pediatric solid tumors. We investigated the association of telomeric alterations with risk of pediatric solid tumors. We also investigated whether altered telomeres cooperated with the TP53 rs1042522, MDM2 rs2279744 and CDKN1A (p21cip1 ) rs1059234 single-nucleotide polymorphisms to modify cancer risk. A total of 101 tumor patients and 202 controls were recruited for this age- and gender-matched case-control study. Relative telomere length (RTL) was determined in peripheral blood leukocytes using quantitative real-time polymerase chain reaction (PCR), and the polymorphisms were genotyped using PCR-restriction fragment length polymorphism. Using median RTL in the healthy controls as a cut-off, children with longer telomeres were at an increased risk of developing a solid tumor (OR, 2.70; P<0.01). When participants were categorized according to control RTL quartiles, a significant dose-response relationship was observed (χ2 =10.95; P<0.001). The risk for tumors increased nearly threefold (P=0.001) for the triple interaction RTL × TP53 rs1042522×p21cip1 rs1059234 compared with the maximum effect of any single factor, although the interaction effect was less than additive. The MDM2 rs2279744 GG genotype reduced pediatric solid tumor risk significantly (OR, 0.51). Combined analysis of telomeres and genetic polymorphisms in the TP53 pathway can provide important clues to understanding pediatric solid tumor etiology.

Genetic Susceptibility in Head and Neck Squamous Cell Carcinoma in a Spanish Population.

Despite classical environmental risk factors like tobacco, alcohol or viral infection, not all individuals develop head and neck cancer. Therefore, identification of the genetic susceptibility produced by single nucleotide polymorphisms (SNPs) is an important task. A total of 296 human papillomavirus negative head and neck cancer (HNC) patients (126 laryngeal, 100 pharyngeal and 70 oral cavity) were included in the study, involving 29 candidate SNPs in genes within important carcinogenic pathways (oncogenesis and tumour suppression, DNA repair, inflammation, oxidation and apoptosis). Genotyping was performed using TaqMan probes or restriction fragment length assays in peripheral blood DNA. In addition, 259 paired controls were also evaluated with the same risk factors for each specific location. Nine SNPs in DNA repair (ERCC1 rs11615, ERCC2 rs13181), inflammatory (IL2 rs2069762, IL6 rs1800795), oxidative (NFE2L2 rs13035806 and rs2706110) and apoptotic genes (TP53 rs1042522, MDM2 rs2279744, BCL2 rs2279115) were differently associated with HNSCC susceptibility by location. Some of these SNPs were not described before in this tumour type. In conclusion, we describe several SNPs associated with HNC in a Spanish population.

Association between MDM2 rs2279744, MDM2 rs937283, and p21 rs1801270 polymorphisms and retinoblastoma susceptibility.

Retinoblastoma (Rb) is the most common intra-ocular malignancy in children. The association of rs2279744, and rs937283 in MDM2 gene, and p21 rs1801270 polymorphism and RB development have been demonstrated. To provide a comprehensive assessment of and to clarify associations between the 3 SNPs (MDM2 rs2279744, MDM2 rs937283, and p21 rs1801270) and the risk of RB, we performed a meta-analysis of all the eligible case-control studies. We searched English databases include PubMed, Embase, Google Scholar, and Cochrane Library, using an upper date limit of January 1, 2018. The association between MDM2 rs2279744, MDM2 rs937283, and p21 rs1801270 polymorphisms and the risk of RB were estimated by calculating a pooled OR and 95% CI under a homozygote comparison, heterozygote comparison, dominant model, and recessive model. The statistical power analysis was performed using G∗Power. Our meta-analysis showed a significant association between RB susceptibility and MDM2 rs2279744 recessive model (OR = 1.427, 95%CI: 1.107-1.840, P = .006, I2 = 0%). Moreover, a significant link was observed between RB risk and MDM2 rs937283 homozygote comparison (OR = 0.471, 95%CI: 0.259-0.858, P = .014, I2 = 0%) and recessive model (OR = 0.587, 95%CI: 0.410-0.840, P = .004, I2 = 0%). However, no significant relationship between the p21 rs1801270 polymorphism and RB susceptibility was detected in any of the 4 models (P > .05). In conclusion, we found that significant association between the MDM2 rs2279744 polymorphism and increased RB risk, while MDM2 rs937283 polymorphism was associated with significantly decreased RB risk. However, as to the P21 rs1801270 polymorphism, a statistically significant association was not identified for RB.

The MDM2 rs937283 A>G variant significantly increases the risk of lung and gastric cancer in Chinese population.

Currently, the MDM2 promoter rs937283 A > G variant that is able to alter MDM2 gene expression has been widely studied to explore the association of MDM2 with cancer risk. In this report, we investigate the association of MDM2 rs937283 A > G variant with risk of lung cancer (LC) and gastric cancer(GC) in a Chinese population of Hubei province, which was followed by a meta-analysis. The genotyping of rs937283 was performed by polymerase chain reaction-restriction fragment length polymorphism and confirmed by sequencing. The results of the present study showed that rs937283 was significantly associated with the risk of LC, and the factors of age, gender, smoking status and drinking status would affect such association. However, rs937283 was only associated with the risk of GC in male, smoking and drinking subgroups. The following meta-analysis demonstrated that rs937283 was associated with the overall cancer risk particularly in Chinese population, which reinforced our present finding. Moreover, the meta-analysis according to cancer types revealed that rs937283 was associated with retinoblastoma risk, but not squamous cell carcinoma risk. Collectively, the MDM2 rs937283 A > G variant may be a valuable risk factor or diagnostic biomarker for Chinese cancer patients.

The Study of MDM2 rs937283 Variant and Cancer Susceptibility in a Central Chinese Population.

The rs937283 variant, locating in murine double minute 2 promoter region, has been previously reported to potentially alter the promoter activity and to influence cancer susceptibility. In this study, we investigated the association of murine double minute 2 rs937283 variant and cancer susceptibility in a central Chinese population, followed by a meta-analysis. A total of 1058 healthy controls, 480 patients with breast cancer, 384 patients with cervical cancer, 480 patients with liver cancer, 426 patients with colon cancer, and 361 patients with rectal cancer were recruited in this case–control study. The murine double minute 2 rs937283 was genotyped by polymerase chain reaction restriction fragment length polymorphism and confirmed by sequencing. Our case–control analysis revealed that rs937283 was associated with the susceptibility to breast and liver cancer, but not cervical, colon, or rectal cancer. Specifically, the G allele of rs937283 conferred a significantly increased risk of breast and liver cancer. Moreover, results of meta-analysis demonstrated that rs937283 was significantly associated with cancer susceptibility, and this significant association remained in Asian (Chinese) population, but not in Caucasian population. Collectively, the murine double minute 2 rs937283 variant may serve as a potential biomarker for cancer predisposition in Chinese population.

Lack of Associations of the MDM4 rs4245739 Polymorphism with Risk of Thyroid Cancer among Iranian-Azeri Patients: a Case-Control Study

Background and Aim:MDM4, a negative regulator of the p53 tumor suppression pathway, has been demonstrated to be overexpressed in a variety of human cancers. Research has revealed that the rs4245739 A>C polymorphism of MDM4 in the 3’-untranslated region makes it a miR-191 target site, leading to lower MDM4 expression. This study aimed to detect if the rs4245739 single nucleotide polymorphism (SNP) impacts on thyroid cancer (TC) development in Iranian-Azeri patients.Materials and Method:Blood samples were taken from 232 healthy controls and 130 TC patients of Iranian-Azeri ethnicity. For genotyping, Tetra-ARMS PCR was performed. SPSS for Windows (version 22.0, IBM SPSS Inc., USA) and the SHEsis online software were used for data analysis.Results:Alleles of MDM4 rs4245739 SNP demonstrated no significant different in frequencies between patients and controls (p>0.05). Additionally, genotypes of MDM4 rs4245739 SNP did not increase or decrease TC risk in patients compared with healthy subjects.Conclusion:Considering the lack of any observed association between the MDM4 rs4245739 polymorphism and TC, we conclude no significant role in the pathophysiology of the disease.