Endometrial cancer and genetic variation in PTEN, PIK3CA, AKT1, MLH1, and MSH2 within a population-based case-control study

Phospho-DIGE Identified Phosphoproteins Involved in Pathways Related to Tumour Growth in Endometrial Cancer

Endometrial cancer (EC) is the most common gynecologic malignancy of the endometrium. This study focuses on EC and normal endometrium phosphoproteome to identify differentially phosphorylated proteins involved in tumorigenic signalling pathways which induce cancer growth. We obtained tissue samples from 8 types I EC at tumour stage 1 and 8 normal endometria. We analyzed the phosphoproteome by two-dimensional differential gel electrophoresis (2D-DIGE), combined with immobilized metal affinity chromatography (IMAC) and mass spectrometry for protein and phosphopeptide identification. Quantities of 34 phosphoproteins enriched by the IMAC approach were significantly different in the EC compared to the endometrium. Validation using Western blotting analysis on 13 patients with type I EC at tumour stage 1 and 13 endometria samples confirmed the altered abundance of HBB, CKB, LDHB, and HSPB1. Three EC samples were used for in-depth identification of phosphoproteins by LC-MS/MS analysis. Bioinformatic analysis revealed several tumorigenic signalling pathways. Our study highlights the involvement of the phosphoproteome in EC tumour growth. Further studies are needed to understand the role of phosphorylation in EC. Our data shed light on mechanisms that still need to be ascertained but could open the path to a new class of drugs that could hinder EC growth.

Endometrial Cancer Staging: Is There Value in ADC?

PURPOSE

To assess the ability of apparent diffusion coefficient (ADC) measurements in predicting the histological grade of endometrial cancer. A secondary goal was to assess the agreement between MRI and surgical staging as an accurate measurement.

METHODS

Patients with endometrial cancers diagnosed between 2018-2020 and having received both MRI and surgical staging were retrospectively enrolled. Patients were characterized according to histology, tumor size, FIGO stage (MRI and surgical stage), and functional MRI parameters (DCE and DWI/ADC). Statistical analysis was performed to determine if an association could be identified between ADC variables and histology grade. Secondarily, we assessed the degree of agreement between the MRI and surgical stages according to the FIGO classification.

RESULTS

The cohort included 45 women with endometrial cancer. Quantitative analysis of ADC variables did not find a statistically significant association with histological tumor grades. DCE showed higher sensitivity than DWI/ADC in the assessment of myometrial invasion (85.00% versus 65.00%) with the same specificity (80.00%). A good agreement between MRI and histopathology for the FIGO stage was found (kappa of 0.72, p < 0.01). Differences in staging between MRI and surgery were detected in eight cases, which could not be justified by the interval between MRI and surgery.

CONCLUSIONS

ADC values were not useful for predicting endometrial cancer grade, despite the good agreement between MRI interpretation and histopathology of endometrial cancer staging at our center.

Endometrial cancer: a genetic point of view

BACKGROUND

Endometrial cancer is the fourth most frequent gynecological cancer and the most frequent type of uterine cancer. There is an increase in the incidence and mortality of uterine cancers in the past few decades, and there are no well-established screening programs for endometrial cancer currently. Most endometrial cancers arise through the interplay of familial, genetic, and lifestyle factors. Although a number of genetic factors modify endometrial cancer susceptibility, they are not of standard use in the clinical assessment of prognosis. We conducted a comprehensive systematic literature review to provide an overview of the relationship between genetic factors and risk for endometrial cancer.

METHODS

MEDLINE and EMBASE databases were searched for studies between January 2010 to March 2020 reporting the genes associated with endometrial cancer.

RESULTS

Through the selection process, we retrieved 186 studies comprising 329 genes identified using several molecular methodologies in all human chromosomes and in mitochondrial DNA. Endometrial cancer exhibits a molecular complexity and heterogeneity coherent with its clinical and histologic variability. Improved characterization of molecular alterations of each histological type provides relevant information about the prognosis and potential response to new therapies.

CONCLUSIONS

The current challenge is the integration of clinicopathologic and molecular factors to improve the diagnosis, prognosis, and treatment of endometrial cancer.

Correlation Between Single Nucleotide Polymorphisms of an miRNA Binding Site in the 3'UTR of PTEN and Risk of Cervical Cancer Among the Han Chinese

Objective: To analyze the association between a single nucleotide polymorphism (SNP) in the 3' untranslated region (UTR) of the phosphatase and tensin homolog (PTEN) gene, that is within a microRNA (miRNA) binding site, and the risk of Chinese Han cervical cancer. Methods: A case-control study was carried out to analyze the genotype of the PTEN rs34140758 locus in 210 surgically treated, Han Chinese, cervical cancer patients and 210 healthy controls. The levels of the miRNAs hsa-miR-586 and hsa-miR-622 and the PTEN mRNA were analyzed by real-time reverse transcription-quantitative polymerase chain reaction in the cancerous and adjacent normal tissues from all cases. HeLa cells were transfected with the miRNAs, hsa-miR-586 and hsa-miR-622, to analyze their effects on PTEN gene expression. Results: After adjusting for age, body-mass index, alcohol consumption, smoking, and familial history of cancer, the PTEN rs34140758 A allele carriers were 1.47 times more likely to suffer from cervical cancer than the C allele carriers (odds ratio [OR] = 1.47, 95% confidence interval [CI]: 1.17-1.72, p = 0.001). Both hsa-miR-586 and hsa-miR-622 were highly expressed in the cancerous tissues of the cervical cancer patients, whereas PTEN expression was low. HeLa cell transfection experiments showed that hsa-miR-586 and hsa-miR-622 inhibited PTEN gene expression. The results of a dual-luciferase reporter assay showed that the PTEN gene is a target for both hsa-miR-586 and hsa-miR-622. Conclusion: The PTEN 3'UTR rs34140758 locus SNP is associated with the risk of cervical cancer in the Han Chinese population. The molecular mechanism may be that the rs34140758 SNP affects the regulation of PTEN gene expression through interaction with the hsa-miR-586 and hsa-miR-622 miRNAs.

Prognostic Role of Krüppel-Like Factors 5, 9, and 11 in Endometrial Endometrioid Cancer

BACKGROUND AND OBJECTIVE

Krüppel-like factors (KLFs) are transcription factors with the ability to mediate cross-talk with signaling pathways involved in cell proliferation control, apoptosis, migration, and differentiation. They also appear to influence steroid hormone signaling through transcriptional networks involving steroid hormone receptors and members of the nuclear receptor family of transcription factors. Our study aims to evaluate the potential prognostic role of KLF5, KLF9, and KLF11 in endometrial cancer, and their correlation with hormonal receptor status and cellular proliferation.

MATERIALS AND METHODS

Retrospective observational study on cases of endometrioid endometrial adenocarcinoma collected in the period January 2000-December 2011 at the University of Udine. Formalin-fixed, paraffin-embedded tissue samples were all submitted to tissue microarray immunohistochemical study. A survival analysis was performed.

RESULTS

One hundred forty seven patients were included in the study with a mean age at surgery of 65.6 years (±10.2). 80.3% of endometrial malignancies were classified as stage FIGO I (118/147). Radiation therapy and chemotherapy were administered in 62.3% (91/146) and 6.2% (9/145) of patients respectively. Five-year overall survival and disease-free survival resulted 85.4% (95% CI, 79.8-91.4%) and 79.4% (95% CI, 73.0-86.4%) respectively. A high Ki-67, cytoplasmatic KLF5 (HR 4.72, CI.95 1.61-13.89, p < 0.05), and nuclear KLF11 (HR 3.04, CI.95 0.99-9.36, p = 0.053) scores correlated with a shorter overall survival. In addition, a high nuclear KLF11 (HR 2.59, CI.95 1.13-5.95, p < 0.05) score correlated with a shorter disease-free survival.

CONCLUSIONS

In patients affected by endometrioid endometrial carcinoma, higher staining levels of KLF5 and KLF11 correlated with a poorer prognosis. However, further studies are required in order to better clarify the role of KLFs in the natural history of endometrial cancer.

Association between genetic polymorphisms and endometrial cancer risk: a systematic review

Introduction

Endometrial cancer is one of the most commonly diagnosed cancers in women. Although there is a hereditary component to endometrial cancer, most cases are thought to be sporadic and lifestyle related. The aim of this study was to systematically review prospective and retrospective case–control studies, meta-analyses and genome-wide association studies to identify genomic variants that may be associated with endometrial cancer risk.

Methods

We searched MEDLINE, Embase and CINAHL from 2007 to 2019 without restrictions. We followed PRISMA 2009 guidelines. The search yielded 3015 hits in total. Following duplicate exclusion, 2674 abstracts were screened and 453 full-texts evaluated based on our pre-defined screening criteria. 149 articles were eligible for inclusion.

Results

We found that single nucleotide polymorphisms (SNPs) in HNF1B, KLF, EIF2AK, CYP19A1, SOX4 and MYC were strongly associated with incident endometrial cancer. Nineteen variants were reported with genome-wide significance and a further five with suggestive significance. No convincing evidence was found for the widely studied MDM2 variant rs2279744. Publication bias and false discovery rates were noted throughout the literature.

Conclusion

Endometrial cancer risk may be influenced by SNPs in genes involved in cell survival, oestrogen metabolism and transcriptional control. Larger cohorts are needed to identify more variants with genome-wide significance.

GOG 8020/210: Risk stratification of lymph node metastasis, disease progression and survival using single nucleotide polymorphisms in endometrial cancer: An NRG oncology/gynecologic oncology group study

OBJECTIVES

The ability to stratify a patient's risk of metastasis and survival permits more refined care. A proof of principle study was undertaken to investigate the relationship between single nucleotide polymorphisms (SNPs) in literature based candidate cancer genes and the risk of nodal metastasis and clinical outcome in endometrioid endometrial cancer (EEC) patients.

METHODS

Surgically-staged EEC patients from the Gynecologic Oncology Group or Washington University School of Medicine with germline DNA available were eligible. Fifty-four genes represented by 384 SNPs, were evaluated by Illumina Custom GoldenGate array. Association with lymph node metastases was the primary outcome. Progression-free survival (PFS) and overall survival (OS) was also evaluated.

RESULTS

361 SNPs with high quality genotype data were evaluated in 337 patients with outcome data. Five SNPs in CXCR2 had an odds ratio (OR) between 0.68 and 0.70 (p-value ≤ 0.025). The A allele rs946486 in ABL had an OR of 1.5 (p-value = 0.01) for metastasis. The G allele in rs7795743 in EGFR had an OR for metastasis of 0.68 (p-value = 0.02) and hazard ratio (HR) for progression of 0.66 (p-value = 0.004). Importantly, no SNP met genome wide significance after adjusting for multiple test correcting and clinical covariates. The A allele in rs2159359 SNP in NME1 and the G allele in rs13222385 in EGFR were associated with worse OS. Both exhibited genome wide significance; rs13222385 remained significant after adjusting for prognostic clinical variables.

CONCLUSION

SNPs in cancer genes including rs2159359 SNP in NME1 and rs13222385 in EGFR may stratify risk in EEC and are prioritized for further investigation.

Association between single nucleotide polymorphisms in the PI3K/AKT/mTOR pathway and bladder cancer risk in a sample of Iranian population

In the past few years several investigations have focused on the role of PI3K/AKT/mTOR pathway and its deregulations in different cancers. This study aimed to examine genetic polymorphisms of this pathway in bladder cancer (BC). In this case-control study, 235 patients with pathologically confirmed bladder cancer and 254 control subjects were examined. PIK3CA, AKT1 and mTOR variants were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The findings proposed that the PIK3CA rs6443624 SNP significantly decreased the risk of BC (OR=0.44, 95 % CI=0.30-0.65, p<0.0001 CA vs CC; OR=0.35, 95 % CI=0.16-0.78, p=0.0107, AA vs CC; OR=0.60, 95 % CI=0.46-0.79, p=0.0002, A vs T). The AKT1 rs2498801 variant is associated with a decreased risk of BC (OR=0.57, 95 % CI=0.39-0.82, p=0.003, AG vs AA; OR=0.74, 95 % CI=0.56-0.97, p=0.032, G vs A) while, AKT1 rs1130233 polymorphism considerably increased the risk of BC (OR=3.70, 95 % CI=2.52-5.43, p<0.0001, GA vs GG; OR=5.81, 95 % CI=1.53-21.97, p=0.010, AA vs GG; OR=2.71, 95 % CI=1.98-3.70, p<0.0001, A vs G). Additionally, mTOR rs2295080 variant notably increased the risk of BC (OR=2.25, 95 % CI=1.50-3.38, p<0.0001, GT vs GG; OR=4.75, 95 % CI=2.80-8.06, p<0.0001, TT vs GG; OR=3.10, 95 % CI=2.34-4.10, p<0.0001, T vs G). None of the other examined polymorphisms (AKT1 rs1130214, AKT1 rs3730358, mTOR rs1883965) revealed significant association with BC. In conclusion, our findings suggest that PIK3CA rs6443624, AKT1 rs2498801, AKT1 rs1130233, as well mTOR rs2295080 polymorphism may be related to bladder cancer development in a sample of Iranian population. Validation of our findings in larger sample sizes of different ethnicities would provide evidence on the role of variants of PI3K/AKT/mTOR pathway in developing BC.

Single nucleotide polymorphisms rs701848 and rs2735343 in PTEN increases cancer risks in an Asian population

We performed this meta-analysis to analyze the cancer risk to individuals carrying the rs701848 and rs2735343 single nucleotide polymorphisms (SNPs) in the phosphatase and tensin homolog (PTEN) gene. We searched the PubMed, EMBASE, Cochrane library and the national knowledge infrastructure of China (CNKI) databases and identified 18 eligible case-control studies with 5458 cases and 6003 controls for rs701848 as well as 5490 cases and 6209 controls for rs2735343. Our analyses demonstrated that cancer risk was associated with rs701848 in the recessive model (CC vs. CT+TT, OR=1.169, 95% CI: 1.061-1.288) and with rs2735343 in the dominant model (GC+CC vs. GG, OR=0.758, 95% CI: 0.590-0.972). Subgroup analysis showed that in Asian subjects, carrying the C allele of rs701848 or GG genotype of rs2735343 was associated with increased cancer risk. Moreover, Asian subjects carrying the TC/CC genotype or C allele of rs701848 were associated with increased risk of esophageal squamous cell cancer. This meta-analysis indicates that the PTEN rs701848 (CC) and rs2735343 (GG) polymorphisms are associated with increased cancer risk in Asian subjects.

Pooling-analysis on hMLH1 polymorphisms and cancer risk: evidence based on 31,484 cancer cases and 45,494 cancer-free controls

To elucidate the veritable relationship between three hMLH1 polymorphisms (rs1800734, rs1799977, rs63750447) and cancer risk, we performed this meta-analysis based on overall published data up to May 2017, from PubMed, Web of knowledge, VIP, WanFang and CNKI database, and the references of the original studies or review articles. 57 publications including 31,484 cancer cases and 45,494 cancer-free controls were obtained. The quality assessment of six articles obtained a summarized score less than 6 in terms of the Newcastle-Ottawa Scale (NOS). All statistical analyses were calculated with the software STATA (Version 14.0; Stata Corp, College Station, TX). We found all the three polymorphisms can enhance overall cancer risk, especially in Asians, under different genetic comparisons. In the subgroup analysis by cancer type, we found a moderate association between rs1800734 and the risk of gastric cancer (allele model: OR = 1.14, P = 0.017; homozygote model: OR = 1.33, P = 0.019; dominant model: OR = 1.27, P = 0.024) and lung cancer in recessive model (OR = 1.27, P = 0.024). The G allele of rs1799977 polymorphism was proved to connect with susceptibility of colorectal cancer (allele model: OR = 1.21, P = 0.023; dominate model: OR = 1.32, P <0.0001) and prostate cancer (dominate model: OR = 1.36, P <0.0001). Rs63750447 showed an increased risk of colorectal cancer, endometrial cancer and gastric cancer under all genetic models. These findings provide evidence that hMLH1 polymorphisms may associate with cancer risk, especially in Asians.

Genetic Polymorphisms of TGFB1, TGFBR1, SNAI1 and TWIST1 Are Associated with Endometrial Cancer Susceptibility in Chinese Han Women

Endometrial cancer (EC) is a complex disease involving multiple gene-gene and gene-environment interactions. TGF-β signaling plays pivotal roles in EC development. This study aimed to investigate whether the genetic polymorphisms of TGF-β signaling related genes TGFB1, TGFBR1, SNAI1 and TWIST1 contribute to EC susceptibility. Using the TaqMan Genotyping Assay, 19 tagging-SNPs of these four genes were genotyped in 516 EC cases and 707 controls among Chinese Han women. Logistic regression (LR) showed that the genetic variants of TGFB1 rs1800469, TGFBR1 rs6478974 and rs10733710, TWIST1 rs4721745 were associated with decreased EC risk, and these four loci showed a dose-dependent effect (Ptrend < 0.0001). Classification and regression tree (CART) demonstrated that women carrying both the genotypes of TGFBR1 rs6478974 TT and rs10512263 TC/CC had the highest risk of EC (aOR = 7.86, 95% CI = 3.42-18.07, P<0.0001). Multifactor dimensionality reduction (MDR) revealed that TGFB1 rs1800469 plus TGFBR1 rs6478974 was the best interactional model to detect EC risk. LR, CART and MDR all revealed that TGFBR1 rs6478974 was the most important protective locus for EC. In haplotype association study, TGFBR1 haplotype CACGA carrier showed the lowest EC risk among women with longer menarche-first full term pregnancy intervals (˃11 years) and BMI˂24 (aOR = 0.39, 95% CI = 0.17-0.90, P = 0.0275). These results suggest that polymorphisms in TGFB1, TGFBR1, SNAI1 and TWIST1 may modulate EC susceptibility, both separately and corporately.

The polymorphisms of MSH6 gene are associated with AIDS progression in a northern Chinese population

It has been reported that DNA repair genes play an important role in HIV-1 infection and AIDS progression. One DNA repair pathway, the mismatch repair (MMR) is associated with a wide variety of tumors. However, the role of single nucleotide polymorphisms (SNPs) in the MMR genes and their importance in HIV-1 infection and AIDS progression remain unclear. In the present study, 479 HIV-1-infected and 487 healthy individuals from northern China were genotyped for nine SNPs in the MSH2 gene (rs13019654, rs4608577, rs4952887, rs6726691, rs10191478, rs12999145, rs1981929, rs2042649, rs2303428) and five SNPs in the MSH6 gene (rs2348244, rs3136245, rs3136329, rs2072447, rs7562048). Our results showed that the rs7562048 G allele frequency was significantly higher in the cases with the CD4(+) T-lymphocyte count <200cells/μl than those with >200cells/μl (P=0.001, OR=1.811, 95% CI 1.255-2.614), which is in agreement with the result of the Bonferroni correction. The frequencies of the rs2348244 C allele and rs3136245 T allele were higher in the cases at clinical phase IV than those at clinical phase I+II+III (P=0.026, OR=1.591, 95% CI 1.056-2.398 and P=0.019, OR=1.749, 95% CI 1.096-2.791, respectively); however, this difference is not supported by the Bonferroni correction. There were no significant differences in the frequency of allele, genotype and haplotype of the 14 SNPs between HIV-1-infected individuals and healthy controls (P>0.05). These results suggest that the rs7562048 is associated with the clinical features and that the MSH6 gene polymorphisms likely play an important role in the progression of AIDS in the northern Chinese population.

Genetic association between PIK3CA gene and oral squamous cell carcinoma: a case control study conducted in Chongqing, China

PIK3CA has been shown to be involved in many malignant tumors. This study was designed to determine the expression level of PIK3CA in oral squamous cell carcinoma (OSCC) and the association of gene polymorphisms of PIK3CA with OSCC in Chinese population. The expression of PIK3CA was detected by real-time PCR in tumor and pericarcinomatous tissues of 10 OSCC patients. Nine single-nucleotide polymorphisms (SNPs) of PIK3CA (rs1607237, rs17849079, rs2677764, rs2699887, rs4855094, rs4975596, rs6443624, rs7651265 and rs7736074) in blood of 113 OSCC patients and 184 normal controls were genotyped using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) assay. The gene expression of PIK3CA was significantly higher in tumor tissues of OSCC patients than that in pericarcinomatous tissues (P = 0.012). An increased frequency of the C allele of PIK3CA rs1607237 was observed in OSCC patients as compared with controls; However, the significance was lost after Bonferroni correction (P = 0.048, pc = 0.576). In further stratification analysis, although the frequencies of PIK3CA rs4975596 A allele in male patients and rs1607237 C allele in female patients were increased (P = 0.032, P = 0.020, respectively), the significance was also missing when Bonferroni correction was performed (P c = 0.384, (P c = 0.24, respectively). The prevalence of other SNPs of PIK3CA did not differ between OSCC patients and controls. The expression of PIK3CA was increased in OSCC tumors; however, none of the nine tested SNPs of PIK3CA was associated with susceptibility to OSCC in the studied population.

Intronic and promoter polymorphisms of hMLH1/hMSH2 and colorectal cancer risk in Heilongjiang Province of China

PURPOSE

Given that mismatch repair (MMR) system plays an important role in recognizing and removing insertion/deletion mutations which occur during DNA replication, common variants associated with impaired MMR system may thus increase risk of colorectal cancer (CRC). Therefore, we aimed to demonstrate the associations between common variants in two MMR genes (hMLH1 and hMSH2) and CRC risk.

METHODS

We genotyped 10 intronic/promoter single-nucleotide polymorphisms (SNPs) of hMLH1 and hMSH2 in 451 CRC patients and 630 controls. Associations between genotypes and CRC risk were estimated using odds ratios and 95 % confidence intervals. Gene-gene interactions, as well as gene-environment interactions on CRC risk were also investigated.

RESULTS

We found that IVS15-214T>C and IVS11 + 107A>G of hMSH2 were significantly associated with CRC risk. In dominant model, variant carriers of the two SNPs could decrease risk of CRC by 31 % (ORadj = 0.69, 95 % CI 0.53-0.91, p < 0.01) and 33 % (ORadj = 0.67, 95 % CI 0.47-0.95, p = 0.02), respectively. In addition, IVS7-212T>A, IVS11+183A>G and IVS8+719T>C of hMSH2 were associated with the susceptibility to colon cancer rather than rectal cancer. ATTTGGGT and TCTTAGAC haplotypes were associated with 44 and 45 % decreased risk of CRC, respectively, while ATTTGAGT and TTTCAGAC haplotypes were associated with 1.37-fold and 2.49-fold increased risk of CRC, respectively. There was a significant three-way gene-gene interaction among hMSH2 IVS11+107A>G, IVS11+183A>G and IVS8+719T>C (p < 0.01). Significant gene-environment interactions were observed between hMSH2 IVS15-214T>C and IVS11+107A>G and cereals consumption (both with p < 0.01).

CONCLUSIONS

Our findings suggested that intronic SNPs, gene-gene and gene-environment interactions in hMSH2 might be associated with susceptibility to CRC.

MLH1 polymorphisms and cancer risk: a meta-analysis based on 33 case-control studies

OBJECTIVE

Cumulative evidence suggests that MLH1, the key component in the mismatch pathway, plays an important role in human cancers. Two potential functional polymorphisms (-93G>A and I219V) of MLH1 have been implicated in cancer risk. The aim of this meta-analysis was to summarize the evidence for associations.

METHODS

Eligible studies were identified by searching the electronic literature PubMed, ScienceDirect and Embase databases for relevant reports and bibliographies. Studies were included if of case-control design investigating MLH1 polymorphisms (-93G>A and I219V) and cancer risk with sufficient raw data for analysis. Odds ratios (OR) and 95% confidence intervals (95% CI) were used to evaluate the strength of associations.

RESULTS

Our meta-analysis from 33 published case-control studies showed the variant A allele of -93G>A polymorphism to be associated with increased risk in all genetic models (AA vs. GG: OR = 1.22, 95% CI: 1.03-1.44), especially among non-Asians (AA vs. GG: OR = 1.28, 95% CI: 1.04-1.58). For the I219V polymorphism, however, there was no main effect associated with overall cancer risk in any genetic model.

CONCLUSIONS

The meta-analysis suggested that the MLH1 -93G>A polymorphism may be a biomarker of cancer susceptibility. Large sample association studies and assessment of gene-to-gene as well as gene-to-environment interactions are required to confirm these findings.

Genetic variations in a PTEN/AKT/mTOR axis and prostate cancer risk in a Chinese population

Backgroud

Genetic variations in a PTEN/AKT/mTOR signaling axis may influence cellular functions including cell growth, proliferation and apoptosis, and then increase the individual’s risk of cancer. Accordingly, we explore the association between single nucleotide polymorphisms (SNPs) of these genes and prostate cancer (PCa) in our Chinese population.

Methods

Subjects were recruited from 666 PCa patients and 708 cancer-free controls, and eight SNPs in the PTEN/AKT/mTOR axis were determined by the TaqMan assay. Odds ratios (OR) and 95% confidence intervals (95% CI) were evaluated by logistic regression.

Results

We observed significant associations between PCa risk and mTOR rs2295080 [P = 0.027, OR = 0.85, 95%CI = 0.74–0.98], and AKT2 rs7254617 (P = 0.003, OR = 1.35, 95%CI = 1.11–1.64). When estimated these two SNPs together, the combined genotypes with 2–4 risk alleles (rs2295080 T and rs7254617 A alleles) were associated with an increased risk of PCa compared with 0–1 risk alleles, which was more pronounced among subgroups of age >71 years, smokers, drinkers and no family history of cancer. Results of stratified analyses by cliniopathological parameters revealed that the frequencies of the combined genotypes with 2–4 risk alleles in advanced stage were significantly higher than in localized stage(P = 0.022), but there was no significant association in Gleason score and PSA level.

Conclusion

Our results indicate, for the first time that the two variants in AKT2 and mTOR, particularly the joint genotypes with 2–4 risk alleles may influence PCa susceptibility and progression in Chinese, and the association appeared to be more strong in the subgroup of smokers and drinkers.

Roles of genetic variants in the PI3K and RAS/RAF pathways in susceptibility to endometrial cancer and clinical outcomes

PURPOSE

The phosphatidylinositol 3-kinase (PI3K)/PTEN/AKT/mTOR and Ras/Raf/MEK/ERK pathways have been implicated in endometrial tumorigenesis. In this candidate pathway analysis, we investigated associations between genetic variations in these two pathways and both risk and clinical outcomes of endometrial cancer.

METHODS

We genotyped a total of 48 potentially functional SNPs in 11 key genes (AKT1, AKT2, AKT3, BRAF, FRAP1, KRAS, PDPK1, PIK3CA, PIK3CB, PIK3R1, and PTEN) with the Sequenom genotyping platform in 115 endometrial cancer patients and 230 cancer-free women to evaluate their associations with risk, survival, and recurrence of endometrial cancer.

RESULTS

We found the following: (1) PIK3CA rs6443624 and rs9838411 variants either borderline or significantly decreased risk of endometrial cancer in a dominant model (adjusted odds ratio [OR], 0.62; 95% CI, 0.39-1.00 and 0.59; 95% CI, 0.36-0.95, respectively). Furthermore, there was a statistically significant multiplicative interaction (P (int) = 0.036) between these two loci in risk of endometrial cancer. In contrast, the AKT1 rs2498801 genotype significantly increased risk of endometrial cancer (adjusted OR, 1.94; 95% CI, 1.02-3.67 in a recessive model). (2) In Cox regression analyses, three SNPs (PIK3R1 rs1862162, AKT2 rs892119, and PIK3CA rs2699887) showed significant associations with survival of endometrial cancer patients. (3) KRAS rs7312175 and PIK3CA rs6443624 had significant effects on recurrence of endometrial cancer individually and combined in a locus-dosage manner (adjusted P (trend) = 0.003).

CONCLUSION

These results suggest that common genetic variations in these pathways may modulate risk and clinical outcomes of endometrial cancer. Further replication and functional studies are needed to confirm these findings.