Polymorphisms at long non-coding RNAs and prostate cancer risk in an eastern Chinese population

Long noncoding RNA polymorphisms in gynecological cancers

Gynecological malignancies are one of the main causes of cancer-induced mortality. Despite remarkable recent therapeutic advances, current therapeutic options are not sufficient. Regarding the effect of long noncoding RNAs (lncRNAs) on cell differentiation, proliferation and apoptosis, variations in their expression cause different anomalies, such as tumorigenesis. SNPs influence lncRNA function and expression. LncRNA polymorphisms can predict cancer risk and are effective for early diagnosis and customized therapy. In this literature review, we comprehensively investigate the effect of lncRNA polymorphisms on gynecological cancers. LncRNA-related variants are proposed to evaluate cancer incidence, early detection and management of personalized therapy. Nonetheless, more studies are required to validate the consistency of current findings in numerous samples and across various ethnic groups.

Long Non-Coding RNAs at the Chromosomal Risk Loci Identified by Prostate and Breast Cancer GWAS

Long non-coding RNAs (lncRNAs) are emerging as key players in a variety of cellular processes. Deregulation of the lncRNAs has been implicated in prostate and breast cancers. Recently, germline genetic variations associated with cancer risk have been correlated with lncRNA expression and/or function. In addition, single nucleotide polymorphisms (SNPs) at well-characterized cancer-associated lncRNAs have been analyzed for their association with cancer risk. These SNPs may occur within the lncRNA transcripts or spanning regions that may alter the structure, function, and expression of these lncRNA molecules and contribute to cancer progression and may have potential as therapeutic targets for cancer treatment. Additionally, some of these lncRNA have a tissue-specific expression profile, suggesting them as biomarkers for specific cancers. In this review, we highlight some of the cancer risk-associated SNPs that modulated lncRNAs with a potential role in prostate and breast cancers and speculate on how these lncRNAs may contribute to cancer development.

The POLR2E rs3787016 polymorphism is strongly associated with the risk of female breast and cervical cancer

The rs3787016 polymorphism, in polymerase II polypeptide E (POLR2E), was previously identified as being associated with the risk for prostate cancer, esophageal cancer, breast cancer, papillary thyroid carcinoma and liver cancer, suggesting that rs3787016 may server as a common genetic factor to affect individual susceptibility to cancer. To prove the hypothesis, we here performed a case-control study to explore the association between rs3787016 and cervical cancer risk, and to confirm the association between rs3787016 and breast cancer in a central Chinese population, which was followed by a meta-analysis to precisely estimate the association between rs3787016 and risk of female breast and cervical cancer. The genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and confirmed by sequencing. Our results indicated that rs3787016 was associated with the risk of both breast cancer and cervical cancer, and stratified analysis indicated that the association remained particularly for ≤60 years old females who smoke and drink. Moreover, after grouping breast cancer and cervical cancer together, our meta-analysis demonstrated that rs3787016 was associated with overall cancer risk and breast cancer risk. Collectively, the POLR2E rs3787016 polymorphism may be a valuable biomarker for female breast and cervical cancer predisposition.

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.

The association of POLR2E rs3787016 polymorphism and cancer risk: a Chinese case-control study and meta-analysis

How single nucleotide polymorphisms in long non-coding RNAs are involved in cancer susceptibility remains poorly understood. We hypothesized that polymerase II polypeptide E (POLR2E) rs3787016 polymorphism, identified in a genome-wide association study of prostate cancer, might be a common genetic risk factor for cancer risk. To address this issue, we here conducted a case-control study to investigate the association of POLR2E rs3787016 polymorphism with risk of liver and lung cancer (including 800 normal controls, 480 liver cancer patients, and 550 lung cancer patients), followed by a meta-analysis. The genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism and confirmed by sequencing. Although no significant association was found for rs3787016 with risk of liver or lung cancer, the further stratified analysis identified that rs3787016 contributed to liver cancer risk particularly for over than 60 years individuals who drink. Moreover, the meta-analysis demonstrated that rs3787016 was associated with overall cancer risk and prostate cancer risk. Collectively, the POLR2E rs3787016 polymorphism may be a valuable biomarker for cancer predisposition.

PCA3 rs544190G>A and prostate cancer risk in an eastern Chinese population

Background:

The association of prostate cancer antigen 3 (PCA3) polymorphism (SNP, rs544190G>A) with metastatic prostate cancer in European descent has been reported. Our aim of the current study was to re-validate the effect of PCA3 polymorphism on prostate cancer risk in an Eastern Chinese population and then estimate possible genetic discrepancies among population.

Materials and Methods:

Taqman assay was employed to determine genotype of SNP rs544190 in 1015 ethnic Han Chinese patients with prostate cancer and 1032 cancer-free controls. Simultaneously, odds ratios (OR) and 95% confidence intervals (95%CI) for risk relationship were calculated by logistic regression models.

Results:

The statistically significant relationship between PCA3 rs544190G>A and higher prostate cancer risk was not found. Stratification analysis revealed that there was no remarkable association of rs544190 variant AG/AA genotype with prostate cancer risk in every subgroup, except for patients with Gleason score ≤7(3+4).

Conclusion:

Although the results demonstrated that SNP rs544190 was not involved in prostate cancer risk in Eastern Chinese descent, unlike in European population, these might have clinical implications on prostate cancer heterogeneity around the World. To validate these findings, well-designed studies with different ethnic populations are warranted.

Polymorphism in lncRNA AC008392.1 and its interaction with smoking on the risk of lung cancer in a Chinese population

Purpose

To evaluate the association between rs7248320 in lncRNA AC008392.1 and the risk of lung cancer, this case–control study was carried out in a Chinese population. This study also evaluated the gene–environment interaction between rs7248320 and exposure to smoking status on the risk of lung cancer.

Patients and methods

We conducted a hospital-based case–control study including 512 lung cancer cases and 588 healthy controls. The association between rs7248320 and the risk of lung cancer was analyzed, and the gene–environment interaction was estimated on an additive scale.

Results

The variant genotype of rs7248320 was significantly related to the risk of non-small-cell lung cancer (NSCLC). Individuals carrying homozygous GG genotype had decreased risk of NSCLC, compared with individuals carrying the homozygous wild AA genotype/heterozygote GA genotype (adjusted odds ratio [OR] =0.653, 95% confidence interval [CI] =0.442–0.966, P=0.033). Moreover, in the subgroup of ages, there were statistically significant associations between rs7248320 and the risk of lung cancer and NSCLC in the population over 60 years of age. Compared with individuals carrying genotypes AA/GA, individuals with genotype GG had the lower risk of lung cancer and NSCLC (adjusted ORs were 0.579 and 0.433, 95% CIs were 0.338–0.994 and 0.231–0.811, P-values were 0.048 and 0.009, respectively). Compared with homozygote AA, the homozygote GG was associated with a decreased risk in NSCLC (OR =0.456, 95% CI =0.235–0.887, P=0.021). There were no statistically significant results in gene–environment interactions on an additive scale.

Conclusion

These findings suggest that lncRNA AC008392.1 rs7248320 may be involved in genetic susceptibility to NSCLC in a Chinese population.

The HOTAIR, PRNCR1 and POLR2E polymorphisms are associated with cancer risk: a meta-analysis

Long non-coding RNAs (LncRNAs) have been widely studied and aberrant expression of lncRNAs are involved in diverse cancers. Genetic variation in lncRNAs can influence the lncRNAs expression and function. At present, there are many studies to investigate the association between lncRNAs polymorphisms and cancer susceptibility. However, it has no systematic study to evaluate the association. We performed a meta-analysis to summarize the results of common lncRNAs (HOTAIR, PRNCR1, POLR2E and H19) polymorphisms on cancer risk, by using the random-effect model to obtain the odds ratio (ORs) and 95% confidence interval (95%CI). We also applied the meta-regression and publication bias analysis to seek the source of heterogeneity and evaluate the stability of results, respectively. The summary results indicated that HOTAIR rs920778 increased the cancer risk in recessive model (OR = 1.61, 95% CI = 1.08-2.41, P_{heterogeneity}<0.001). For PRNCR1 (rs1016343, rs16901946) and POLR2E (rs3787016), we also found the significant association with incresed risk of cancer (all P<0.05). However, we did not observe any significant association between H19 rs2107425 and cancer risk. Our meta-analysis results revealed that these four lncRNAs polymorphisms (HOTAIR rs920778, PRNCR1 rs1016343 and rs16901946, POLR2E rs3787016) can contribute to cancer risk. Further studies should confirm these findings.

Single nucleotide polymorphisms and cancer susceptibility

A large number of genes associated with various cancer types contain single nucleotide polymorphisms (SNPs). SNPs are located in gene promoters, exons, introns as well as 5'- and 3'- untranslated regions (UTRs) and affect gene expression by different mechanisms. These mechanisms depend on the role of the genetic elements in which the individual SNPs are located. Moreover, alterations in epigenetic regulation due to gene polymorphisms add to the complexity underlying cancer susceptibility related to SNPs. In this systematic review, we discuss the various genetic and epigenetic mechanisms involved in determining cancer susceptibility related to various SNPs located in different genetic elements. We also discuss the diagnostic potential of these SNPs and the focus for future studies.

Association between SNPs in Long Non-coding RNAs and the Risk of Female Breast Cancer in a Chinese Population

Long non-coding RNAs (LncRNAs) have been reported to be involved in tumorigenesis and tumor progression. Single nucleotide polymorphisms (SNPs) in the lncRNAs also play a vital role in carcinogenesis. The aim of this study was to assess the relationships between the four selected tagSNPs (rs944289, rs3787016, rs1456315, rs7463708) in the lncRNAs and the risk of female breast cancer in a Chinese population. A case-control study was carried out involving in a total of 439 breast cancer patients and 439 age-matched healthy controls. The genotyping was performed with Sequenom MassARRAY and the expression of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER-2) in tumor tissues was measured by the immunohistochemistry (IHC) assay. We found that rs3787016 TT genotype (adjusted odds ratio (OR) = 1.62, 95% confidence interval (CI) = 1.09-2.41, P = 0.018) was associated with an increased risk of female breast cancer, especially among the patients with premenopausal status (adjusted OR = 2.55, 95% CI = 1.30-4.97, P = 0.006). Moreover, a statistically significant increased risk of the rs3787016 TT genotype was observed among the patients with advanced tumor stage (Ⅲ and Ⅳ), poor histological grade (G3-G4), positive lymph node involvement, positive expression of ER and PR and negative expression of HER-2; rs7463708 GT and GT/GG genotype were associated with decreased risk of breast cancer in the subgroup of patients with postmenopausal status (GT versus (vs.) TT: adjusted OR = 0.67, 95% CI = 0.46-0.99, P = 0.043; GT/GG vs. TT: adjusted OR = 0.68, 95% CI = 0.47-0.98, P = 0.041) and tumor late-stage (GT vs. TT: adjusted OR = 0.65, 95% CI = 0.43-0.97, P = 0.037; GT/GG vs. TT: adjusted OR = 0.65, 95% CI = 0.44-0.96, P = 0.029). In short, rs3787016 TT genotype was associated with increased breast cancer risk and clinicopathologic features of the tumor, especially among premenopausal women.

Long Non-Coding RNA as Potential Biomarker for Prostate Cancer: Is It Making a Difference?

Whole genome transcriptomic analyses have identified numerous long non-coding RNA (lncRNA) transcripts that are increasingly implicated in cancer biology. LncRNAs are found to promote essential cancer cell functions such as proliferation, invasion, and metastasis, with the potential to serve as novel biomarkers of various cancers and to further reveal uncharacterized aspects of tumor biology. However, the biological and molecular mechanisms as well as the clinical applications of lncRNAs in diverse diseases are not completely understood, and remain to be fully explored. LncRNAs may be critical players and regulators in prostate cancer carcinogenesis and progression, and could serve as potential biomarkers for prostate cancer. This review focuses on lncRNA biomarkers that are already available for clinical use and provides an overview of lncRNA biomarkers that are under investigation for clinical development in prostate cancer.

A systematic review and meta-analysis of the association between long non-coding RNA polymorphisms and cancer risk

It has been suggested that long non-coding RNA (lncRNA) gene polymorphisms are associated with cancer risk. In this article, we conducted a systematic review related to studies on the association between lncRNA single-nucleotide polymorphisms (SNPs) and the overall risk of cancer. A total 17 SNPs in four common lncRNA genes were included in the meta-analysis. In the lncRNA H19, the rs2735971 A/G, rs2839698C/T, and rs3024270 G/C polymorphisms, but not rs217727C/T, were correlated with overall cancer risk. The results also suggested that other SNPs were correlated with overall cancer risk, namely, two in HOTAIR (HOX transcript antisense RNA: rs920778C/T and rs7958904 G/C) and two in PRNCR1 (rs1016343C/T and rs16901946 A/G). No association was found between the three ZNRD1-AS1 (ZNRD1 antisense RNA 1) SNPs and the risk of cancer. In summary, our findings suggest that quite a few studied lncRNA SNPs are associated with overall cancer risk; therefore, they are potential predictive biomarkers for the risk of cancer. Moreover, other lncRNA SNPs investigated were also relevant to cancer but studies on them are limited, and they were also briefly reviewed as candidate cancer markers.

Non-Coding RNAs in Castration-Resistant Prostate Cancer: Regulation of Androgen Receptor Signaling and Cancer Metabolism

Hormone-refractory prostate cancer frequently relapses from therapy and inevitably progresses to a bone-metastatic status with no cure. Understanding of the molecular mechanisms conferring resistance to androgen deprivation therapy has the potential to lead to the discovery of novel therapeutic targets for type of prostate cancer with poor prognosis. Progression to castration-resistant prostate cancer (CRPC) is characterized by aberrant androgen receptor (AR) expression and persistent AR signaling activity. Alterations in metabolic activity regulated by oncogenic pathways, such as c-Myc, were found to promote prostate cancer growth during the development of CRPC. Non-coding RNAs represent a diverse family of regulatory transcripts that drive tumorigenesis of prostate cancer and various other cancers by their hyperactivity or diminished function. A number of studies have examined differentially expressed non-coding RNAs in each stage of prostate cancer. Herein, we highlight the emerging impacts of microRNAs and long non-coding RNAs linked to reactivation of the AR signaling axis and reprogramming of the cellular metabolism in prostate cancer. The translational implications of non-coding RNA research for developing new biomarkers and therapeutic strategies for CRPC are also discussed.