CDKN1B Val 109 Gly variant is not related to risk of prostate cancer

Association between CDKN1B gene Val 109 Gly polymorphism and prostate cancer (PCa) susceptibility has been investigated in several studies but with inconsistent conclusions. We adopted odds ratios (ORs) and 95% confidence intervals (CIs) to assess the correlation between CDKN1B Val 109 Gly variant and PCa susceptibility. Moreover, we used in-silico tools to evaluate the relationship of CDKN1B expression and overall survival (OS) or disease free survival (DFS) time in PCa patients. The overall results demonstrated no association of the CDKN1B variant on PCa risk [allelic contrast (OR = 0.78, 95% CI = 0.45 − 1.35, P_{heterogeneity} = 0.038); GV vs VV (OR = 0.83, 95% CI = 0.56 − 1.25, P_{heterogeneity} = 0.253); GG vs VV (OR = 0.48, 95% CI = 0.23 − 1.01, P_{heterogeneity} = 0.161); GG+GV vs VV (OR = 0.75, 95% CI = 0.52 −1.08, P_{heterogeneity} = 0.132) and GG vs GV+VV (OR = 0.63, 95% CI = 0.25 − 1.11, P_{heterogeneity} = 0.152)]. In subgroup analysis by ethnicity and source of control, we also identified similar results. In-silico results showed that expression of CDKN1B was decreased in PCa tissue, especially in less advanced PCa (Gleason score = 6 or 7). No significant difference of OS or DFS time was indicated between the low and high expression of CDKN1B. Our present study showed evidence that CDKN1B Val 109 Gly variant is not related to PCa risk. Future studies with large sample size are needed to confirm this correlation in more details.     

Manganese superoxide dismutase (MnSOD) genetic polymorphism is associated with risk of early-onset prostate cancer

Prostate cancer continues to be the most frequently diagnosed neoplasm, and the second leading cause of cancer-related mortality in men. Oxidative stress may enhance prostatic carcinogenesis. Manganese superoxide dismutase (MnSOD) is the only known superoxide scavenger in mitochondria. It plays a key role in antioxidant defense as mitochondria are important for oxidative metabolism coupled to the electron transport chain and oxidative phosphorylation and hence, ROS production. A T-->C single nucleotide substitution, resulting in a Val-->Ala change at position 9 (Ala-9Val), which alters the secondary structure of the protein, has been noted to affect transport of MnSOD into the mitochondria. We have determined the MnSOD genotype in 85 prostate cancer cases and 151 control subjects. Ala-9Val polymorphism was determined using real time polymerase chain reaction (PCR) amplification with fluorescently labeled primers. No significant difference was found in prostate cancer susceptibility in the subjects with Ala/Ala and Val/Ala genotype compared with Val/Val genotype (Odds ratio (OR), 1.3; 95% confidence interval (95% CI), 0.69-2.42; p = 0.416). We did not observe an association of the MnSOD genotype or allele frequency between subgroups of cases divided by disease status (aggressive vs. non-aggressive prostate cancer). However, in the analyses stratified by the age at diagnosis we have observed that men homozygous for Ala had a 5.2-fold increased risk of early-onset prostate cancer (under age of 65) compared to men homozygous for Val allele (p = 0.05). These data suggest that Ala/Ala MnSOD genotype in the Macedonian population could have an influence on early onset of prostate cancer, but no impact on the subsequent development of the disease.     

Localization of MCT2 at peroxisomes is associated with malignant transformation in prostate cancer

Previous studies on monocarboxylate transporters expression in prostate cancer (PCa) have shown that monocarboxylate transporter 2 (MCT2) was clearly overexpressed in prostate malignant glands, pointing it out as a putative biomarker for PCa. However, its localization and possible role in PCa cells remained unclear. In this study, we demonstrate that MCT2 localizes mainly at peroxisomes in PCa cells and is able to take advantage of the peroxisomal transport machinery by interacting with Pex19. We have also shown an increase in MCT2 expression from non‐malignant to malignant cells that was directly correlated with its peroxisomal localization. Upon analysis of the expression of several peroxisomal β‐oxidation proteins in PIN lesions and PCa cells from a large variety of human prostate samples, we suggest that MCT2 presence at peroxisomes is related to an increase in β ‐oxidation levels which may be crucial for malignant transformation. Our results present novel evidence that may not only contribute to the study of PCa development mechanisms but also pinpoint novel targets for cancer therapy.     

Association of RNASEL and 8q24 variants with the presence and aggressiveness of hereditary and sporadic prostate cancer in a hispanic population

To study the association between the polymorphisms Arg462Gln and Asp541Glu from the RNASEL gene (1q25), and the polymorphisms rs620861, rs1447295, rs6983267, rs7837328 from the chromosome 8q24 with the risk of presenting prostate cancer (PCa) and its clinical characteristics in a Hispanic (Chilean) population. The study was performed on 21 control patients and 83 patients diagnosed with PCa. Polymorphisms were analysed from blood samples through real‐time PCR by using TaqMan probes, and the genetic analysis was performed with the SNPStats program. Also, a comparison was performed between clinical characteristics of PCa and the presence of the different polymorphism genotypes by using the Minitab software. There was a significant association between the genotype G/G from the polymorphism rs6983267 with an overall increased risk of PCa, in patients both with or without family history of PCa (OR = 4.47, 95% CI = 1.05–18.94, P = 0.034 and OR = 3.57, 95% CI = 0.96–13.35, P = 0.037, respectively). Regarding clinical parameters, patients carrying the genotype C/C from the polymorphism Asp541Glu had significantly higher prostate‐specific antigen (PSA) levels than patients carrying the other genotypes (P = 0.034). Moreover, patients with the genotype G/G of rs6983267 had higher PSA levels (P = 0.024). The polymorphism rs6983267 from region 3 of the chromosome 8q24 appears to be a prominent risk factor for PCa and a biomarker for cancer aggressiveness in the group of patients who presented higher levels of PSA at the time of diagnosis.     

MTSS1 hypermethylation is associated with prostate cancer progression

This study was conducted to evaluate the influence of DNA methylation of metastasis suppressor 1 (MTSS1) on prostate cancer (PCa) progression. Forty-nine paired PCa tissue samples and normal tissue samples from The Cancer Genome Atlas were analyzed. Methylome analysis, CpG island arrays and Hierarchical clustering were used to analyze methylation profiles of PCa tissues. MTSS1 methylation level was detected by methylation-specific PCR. Relative messenger RNA and the expression level of MTSS1 protein were identified by quantitative real-time PCR (qRT-PCR) and western blot analysis. The migration, invasion, proliferation, and cell cycle were detected separately by wound-healing assay, transwell chamber assay, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and flow cytometry. The roles of MTSS1 in PCa progression were demonstrated in vivo by tumor formation assays in nude mice. MTSS1 expression was decreased in PCa tissues in comparison with paired adjacent normal prostate tissues. Compared to the methylation of MTSS1 in normal prostate tissues based on the MethHC website, the MTSS1 in PCa tissues was hypermethylated. The expression of MTSS1 detected by qRT-PCR and western blot analysis was found to be downregulated in PCa cells and tissues. The reduced expression of MTSS1 by small interfering RNA-MTSS1 was recovered by 5-aza-2′-deoxycytidine treatment. Besides, MTSS1 demethylation inhibited migration, invasion, and proliferation of PCa cells, and induced cell cycle to be arrested at G0/G1 phase. Furthermore, it was shown by tumor xenograft assay that MTSS1 inhibited the growth of tumor in vivo. Hypermethylated MTSS1 promoted PCa cells migration, invasion, and proliferation, and suppressed cell cycle arrest at the G0/G1 phase.     

XPF -673C>T variation is associated with the susceptibility to breast cancer

PurposeXPF variations might decrease the DNA repair capacity and further contribute to cancer development. This study aimed to investigate the association of XPF polymorphisms with risk of developing breast cancer.MethodsTCGA, the Human Protein Atlas and Kaplan-Meier plotter were used to analyze the expression of XPF in breast cancer tissues and its effect on the survival of breast cancer patients. The expression of XPF in breast cancer tissues was detected by qRT-PCR. This case-control study included 467 breast cancer patients and 467 healthy controls. The genotype of genetic variation was detected by polymerase chain reaction restriction fragment length polymorphism. Odds ratios and 95 % confidence intervals were calculated. Correlations between XPF variation and clinicopathological parameters were assessed through Kendall’s Tau-b test. The relationship between XPF gene function variation and XPF gene expression was analyzed by GTEx.ResultsThe expression of XPF in breast cancer tissues is higher than that in normal tissues. Breast cancer patients with high XPF expression have a higher relapse free survival rate (HR = 0.88, 95 % CI = 0.80−0.97), but have no effect on the overall survival rate (logrank P = 0.28). XPF -673C > T variant can reduce the risk of breast cancer patients (OR = 0.35, 95 %CI = 0.20−0.63 for codominant mode; OR = 0.66, 95 %CI = 0.51−0.85 for dominant model; OR = 0.40, 95 %CI = 0.23−0.70 for recessive model). The XPF 11985 GG genotype reduced the risk of early breast cancer (OR = 0.49, 95 %CI = 0.24−0.97), but not the risk of advanced breast cancer (OR = 1.20, 95 % CI = 0.58−2.48). XPF 11985A > G variant can also reduce the risk of ERBB2 expression in patients (OR = 0.50, 95 %CI = 0.27−0.94). There is no correlation between XPF -673C > T/XPF11985A > G variants and ER and PR. XPF -673C > T variant can reduce XPF expression (P < 0.05).ConclusionsGenetic variations of XPF gene may affect its expression and the risk of breast cancer in the Chinese population.     

A naturally occurring variant of Hsp90 that is associated with decanalization

The heat shock protein Hsp90 has been the focus of many studies since it was suggested that it acts to mediate the buffering of phenotypic variation. Hsp90-mediated buffering may result in the accumulation of cryptic genetic variation that, when released either as a consequence of environmental or genetic stress, increases the evolvability of a population. Recent studies using laboratory-induced mutations of Hsp90 and/or chemical inhibition to disrupt Hsp90 function confirm that Hsp90 can buffer cryptic genetic variation. We have previously identified a naturally occurring variant in the charged linker region of the Hsp90 gene, and now examine whether this variant is associated with altered levels of trait variability. The variant is associated with the release of cryptic genetic variation for canalized morphological (bristle) traits, but not for uncanalized morphological (wing and bristle) traits, and the effect on canalized traits depends on culture temperature. This suggests that natural genetic variation in Hsp90 may mediate the evolution of canalized morphological traits even if it does not influence the expression of variation for uncanalized traits.     

Long non-coding RNA POLR2E gene polymorphisms increased the risk of prostate cancer in a sample of the Iranian population

The current study aimed to examine the impact of POLR2E rs1046040 and rs3787016 polymorphisms on prostate cancer (PCa) risk in a sample of southeast Iranian population. The present case-control study was performed on 178 patients with PCa and 180 benign prostatic hyperplasia (BPH). Genotyping of the variants was done by mismatch PCR-RFLP. The findings showed that the rs3787016 C?>?T variant significantly increased the risk of PCa in codominant (OR?=?1.84, 95% CI?=?1.12-3.03, P?=?0.018, CT vs CC), dominant (OR?=?1.88, 95% CI?=?1.63-3.05, P?=?0.011, CT?+?TT vas CC) and allele (OR?=?1.77, 95% CI?=?1.52-2.72, P?=?0.010, T vs C) inheritance model. Regarding rs1046040 C?>?T polymorphism, the findings revealed that the CT genotype significantly increased the risk of PCa compared to the CC genotype (OR?=?1.60, 95% CI?=?1.03-2.49, P?=?0.043). Furthermore, rs3787016 CT/rs1046040?CC as well as rs3787016 CT/rs1046040 CT increased the risk of PCa compared to the CC/CC genotype (p?=?0.029 and p?=?0.014, respectively). Haplotype analysis proposed that rs3787016 T/rs1046040 C significantly increased the risk of PCa compared to C/C (p?=?0.037). No significant association was observed between POLR2E variants and clinicopathological characteristics of PCa patients. In conclusion, the findings propose that POLR2E variants may be a risk factor for susceptibility to PCa in a sample of Iranian population.     

Functional variants of the chitinase 3-like 1 gene are associated with clinicopathologic outcomes and progression of prostate cancer

Chitinase 3-like 1 (CHI3L1 or YKL40) is a secreted glycoprotein highly expressed in advanced stages of several cancer types, including prostate cancer (PCa). Impacts of genetic variants of CHI3L1 on PCa development have not yet been investigated. The most common well-studied genetic variations are single-nucleotide polymorphisms (SNPs). Therefore, the objective of this study was to explore associations of CHI3L1 SNPs with both the susceptibility to PCa and its clinicopathological development. Three promoter SNPs, rs6691378 (−1371, G>A), rs10399805 (−247, G>A) and rs4950928 (−131, C>G), and one non-synonymous SNP, rs880633 (+2950, T>C), were analysed using a TaqMan allelic discrimination assay for genotyping in a cohort of 701 PCa patients and 701 healthy controls. Results indicated that there were no significant associations of PCa susceptibility with these four CHI3L1 SNPs. However, among elderly PCa patients (aged >65 years), it was observed that polymorphic variants (GA + AA) of CHI3L1 rs6691378 and 10399805 were significantly linked to reduced risks of several clinicopathological characteristics, including a high Gleason grade, advanced pathologic T stage and tumour cell invasion. Moreover, analyses of The Cancer Genome Atlas database revealed that CHI3L1 expression levels were elevated in PCa tissues compared with normal tissues. Interestingly, higher CHI3L1 expression levels were found to be associated with longer progression-free survival rates in PCa patients. Our findings indicated that levels of CHI3L1 may influence the progression of PCa, and the rs6691378 and 10399805 SNP genetic variants of CHI3L1 are linked to the clinicopathological development of PCa within a Taiwanese population.     

MicroRNAs that affect prostate cancer: emphasis on prostate cancer in African Americans

Abstract

Although concerted efforts have been directed toward eradicating health disparities in the United States, the disease and mortality rates for African American men still are among the highest in the world. We focus here on the role of microRNAs (miRNAs) in the signaling pathways of androgen receptors and growth factors that promote the progression of prostate cancer to more aggressive disease. We explore also how differential expression of miRNAs contributes to aggressive prostate cancer including that of African Americans.     

Polymorphisms associated with the risk of lung cancer in a healthy Mexican Mestizo population: Application of the additive model for cancer

Lung cancer is the leading cause of cancer mortality in Mexico and worldwide. In the past decade, there has been an increase in the number of lung cancer cases in young people, which suggests an important role for genetic background in the etiology of this disease. In this study, we genetically characterized 16 polymorphisms in 12 low penetrance genes (AhR, CYP1A1, CYP2E1, EPHX1, GSTM1, GSTT1, GSTPI, XRCC1, ERCC2, MGMT, CCND1 and TP53) in 382 healthy Mexican Mestizos as the first step in elucidating the genetic structure of this population and identifying high risk individuals. All of the genotypes analyzed were in Hardy-Weinberg equilibrium, but different degrees of linkage were observed for polymorphisms in the CYP1A1 and EPHX1 genes. The genetic variability of this population was distributed in six clusters that were defined based on their genetic characteristics. The use of a polygenic model to assess the additive effect of low penetrance risk alleles identified combinations of risk genotypes that could be useful in predicting a predisposition to lung cancer. Estimation of the level of genetic susceptibility showed that the individual calculated risk value (iCRV) ranged from 1 to 16, with a higher iCRV indicating a greater genetic susceptibility to lung cancer.     

Replication study of 34 common SNPs associated with prostate cancer in the Romanian population

Prostate cancer is the third‐most common form of cancer in men in Romania. The Romanian unscreened population represents a good sample to study common genetic risk variants. However, a comprehensive analysis has not been conducted yet. Here, we report our replication efforts in a Romanian population of 979 cases and 1027 controls, for potential association of 34 literature‐reported single nucleotide polymorphisms (SNPs) with prostate cancer. We also examined whether any SNP was differentially associated with tumour grade or stage at diagnosis, with disease aggressiveness, and with the levels of PSA (prostate specific antigen). In the allelic analysis, we replicated the previously reported risk for 19 loci on 4q24, 6q25.3, 7p15.2, 8q24.21, 10q11.23, 10q26.13, 11p15.5, 11q13.2, 11q13.3. Statistically significant associations were replicated for other six SNPs only with a particular disease phenotype: low‐grade tumour and low PSA levels (rs1512268), high PSA levels (rs401681 and rs11649743), less aggressive cancers (rs1465618, rs721048, rs17021918). The strongest association of our tested SNP's with PSA in controls was for rs2735839, with 29% increase for each copy of the major allele G, consistent with previous results. Our results suggest that rs4962416, previously associated only with prostate cancer, is also associated with PSA levels, with 12% increase for each copy of the minor allele C. The study enabled the replication of the effect for the majority of previously reported genetic variants in a set of clinically relevant prostate cancers. This is the first replication study on these loci, known to associate with prostate cancer, in a Romanian population.     

The impact of receptor of advanced glycation end-products polymorphisms on prostate cancer progression and clinicopathological characteristics

The receptor for advanced glycation end products (RAGE) overexpression was suggested to be associated with prostate cancer development and poor prognosis. In this study, we focused on the correlations between the clinicopathological characteristics and susceptibility of prostate cancer and RAGE single-nucleotide polymorphisms (SNPs). In 579 prostate cancer patients, the RAGE SNPs rs1800625, rs1800624, rs2070600 and rs184003 in patients with or without grade group upgrade were analysed with real-time polymerase chain reaction. The results demonstrated that the prostate cancer patients who carried the RAGE SNPs rs2070600 ‘GA’ genotypic variants were significantly associated with lower risk to develop grade group upgrade. Moreover, patients with the RAGE rs1800625 ‘TC + CC’ genotypic variants were associated with higher risk of perineural invasion. In 343 prostate cancer patients who carried the RAGE rs1800625 ‘TC + CC’ genotype without grade group upgrade were correlated with higher risk of biochemical recurrence and perineural invasion. In the analysis of TCGA database, significant differences of the RAGE mRNA level were found between the normal controls and prostate cancer patients (p < 0.0001), and the pathologic stage N1 and N0 patients (p = 0.0027). The prostate cancer patients with high RAGE expression were associated with lower overall survival rate (p = 0.025). In conclusion, our results have revealed that the RAGE SNPs rs2070600 and rs1800625 were associated with the grade group upgrade of prostate cancer and clinical status. The RAGE polymorphisms may provide as a pivotal predictor to evaluate prostate cancer disease progression and prognosis.     

Tissue proteomics studies in the investigation of prostate cancer

Introduction: Prostate cancer (PCa) is one of the leading causes of death in the male population worldwide. Various clinical samples such as urine, blood serum, and prostatic fluid have been commonly used for the identification of PCa-associated molecular changes. Tissue, the site of oncogenesis, is increasingly gaining more attention as a study material for studies aimed at the discovery of biomarkers for predicting the disease outcome and therapeutic targets.

Areas covered: This review is the output of a systematic literature search on PubMed to retrieve articles relevant to the proteomic analysis of tissues for the study of PCa. Studies performed during the last 10 years using human tissues are summarized.

Expert commentary: Multiple proteomics studies were performed in the past 10 years focusing on PCa initial diagnosis and staging. Even though some reproducible findings have been reported, many studies lacked adequate validation of findings and relied on relatively lower-resolution proteomics techniques compared to the current state of the art. Incorporation of high-resolution proteomics techniques, including investigations of protein post-translational modifications (PTMs), is expected in the near future to complement other -omics and enhance current efforts toward the molecular subtyping of PCa for patient stratification.     

Association of C-reactive protein (CRP) rs1205 and rs2808630 variants and risk of cancer

The correlation between rs1205, rs2808630 variants of C-reactive protein (CRP) gene and susceptibility of cancer has been assessed previously, but with conflicting results. We adopted odds ratios (ORs) with 95% confidence intervals (CIs), in silico tools and enzyme-linked immunosorbent assay (ELISA) analysis to evaluate this association. Totally, 10,614 cancer subjects and 33,294 controls were involved in the pooled analysis. When all the studies were pooled, no significant correlation was indicated between the two variants and cancer risk. However, in stratification analysis by ethnicity, we found that CRP rs1205 C>T polymorphism was associated with an elevated risk of cancer in Asians (T-allele vs. C-allele, OR = 1.20, 95% CI = 1.06–1.36, p_{heterogeneity} = .226; TT vs. CC, OR = 1.48, 95% CI = 1.14–1.93, p_{heterogeneity} = .089). Similar findings were observed for rs2808630 variant. In silico tools showed that lung adenocarcinoma participants with high CRP expression may have shorter overall survival time than low expression group. ELISA analysis indicated that CRP expression in prostate adenocarcinoma subjects with TT + TC genotypes was statistically higher than in those with CC genotypes. CRP rs1205 C>T and rs2808630 T>C polymorphism may be associated with cancer risk, especially for Asians.     

Cyr61 is up‐regulated in prostate cancer and associated with the p53 gene status

Cysteine‐rich 61 (Cyr61) is a member of the CCN protein family that has been implicated in diverse biological processes such as cell adhesion, proliferation, angiogenesis, and tumorigenesis. Altered expression of Cyr61 is found to be associated with human cancers. Here we show that Cyr61 was up‐regulated in prostate cancer cell lines and tumor tissues. A significant correlation of Cyr61 expression was found between benign prostatic hyperplasia and prostate cancer (P = 0.002). However, there was no significant correlation between levels of PSA and Cyr61 expression (P = 0.2). Cyr61 may represent an independent prostate cancer biomarker and potentially a useful therapeutic target for prostate cancer treatment. In addition, our analysis based on published data and data present in this report indicted that levels of Cyr61 expression associated with the status of the tumor suppressor gene p53 in 32 cancer cell lines analyzed, high levels of Cyr61 expression were found in cell lines with mutant or null p53 gene, whereas lower expression levels of Cyr61 in the cell lines with wild‐type p53. We further show that over‐expression of dominant negative p53 or down‐expression of endogenous wild‐type p53 resulted in up‐regulation of Cyr61 expression, suggesting a functional link between Cyr61 and p53 in cancers. J. Cell. Biochem. 106: 738–744, 2009. © 2009 Wiley‐Liss, Inc.     

A comprehensive study of CD44 rs 187115 variant and cancer risk in a central Chinese population

The rs187115, an intronic variant of CD44 gene, has been previously reported to play a potential role in genetic susceptibility to cancer. Here, we comprehensively examined the association between CD44 rs187115 variant and cancer risk (breast cancer, cervical cancer, lung cancer, gastric cancer, liver cancer, colon cancer, and rectal cancer) in a central Chinese population. The rs187115 variant was genotyped with the polymerase chain reaction-restriction fragment length polymorphism assay. In this study, we observed that rs187115 was associated with the risk of cervical, lung, and liver cancer, but not with the risk of breast, gastric, colon, rectal or colorectal cancer. Of note, the G allele and G allele genotypes of rs187115 conferred an increased risk of cervical, lung, and liver cancer. To improve the statistical strength, a followed meta-analysis was conducted. The results demonstrated that rs187115 was significantly associated with cancer risk, and the significant association remained in the stratification analysis by ethnicity, genotyping method, and cancer type. Collectively, the CD44 rs187115 variant may be associated with the risk of cervical, lung, and liver cancer in the central Chinese population, and may be used as a potential biomarker for cancer predisposition in the Asian population, especially in the Chinese population.     

A common genetic variant of 5p15.33 is associated with risk for prostate cancer in the Chinese population

Recent evidence has suggested that single-nucleotide polymorphisms (SNPs) located at 5p15.33 contribute to susceptibilities for several cancer types, including prostate cancer. To determine whether SNP rs402710 in this region plays a role in prostate cancer, we analyzed these associations in a Chinese population; 251 prostate cancer patients and 273 control subjects were included in this case-control study. Genotypes were determined by PCR-RFLP. We found that subjects carrying the CC homozygote had a decreased risk for prostrate cancer compared to those carrying TT/TC genotypes (odds ratio (OR) = 0.69, 95% confidence interval (CI) = 0.48-0.98, P = 0.038). Compared with the TT homozygote, subjects carrying the CC homozygote also had a decreased risk for prostate cancer (OR = 0.71, 95%CI = 0.51-0.99, P = 0.043). We conclude that rs402710 polymorphisms in the 5p15.33 region are associated with prostate cancer risk in the Chinese population. Further investigations with large cohorts and done worldwide are warranted to determine whether our findings are detected in other populations.