Haplotype Analysis of Prostate Stem Cell Antigen and Association With Prostate Cancer Risk

Significance of PSCA as a novel prognostic marker and therapeutic target for cancer

One of the contributing factors in the diagnosis and treatment of most cancers is the identification of their surface antigens. Cancer tissues or cells have their specific antigens. Some antigens that are present in many cancers elicit different functions. One of these antigens is the prostate stem cell antigen (PSCA) antigen, which was first identified in the prostate. PSCA is a cell surface protein that has different functions in different tissues. It can play an inhibitory role in cell proliferation as well as a tumor-inducing role. PSCA has several genetic variants involved in cancer susceptibility in some tissues, so identifying the characteristics of this antigen and its relationship with clinical features can provide more information on diagnosis and treatment of patients with cancers. Most studies on the PSCA have focused on prostate cancer. While it is also expressed in other cancers, little attention has been paid to its role as a valuable diagnostic, prognostic, and therapeutic tool in other cancers. PSCA has several genetic variants that seem to play a significant role in cancer susceptibility in some tissues, so identifying the characteristics of this antigen and its relationship and variants with clinical features can be beneficial in concomitant cancer therapy and diagnosis, as theranostic tools. In this study, we will review the alteration of the PSCA expression and its polymorphisms and evaluate its clinical and theranostics significance in various cancers.

The PSCA rs2294008 (C/T) Polymorphism Increases the Risk of Gastric and Bladder Cancer: A Meta-Analysis

Background: It has been reported that prostate stem cell antigen (PSCA) is overexpressed in certain cancer types and confers poor prognoses. The rs2294008 (C/T) polymorphism of PSCA is considered to be associated with risk for gastric, bladder, and colorectal cancers; however, these studies have produced inconsistent results, so we performed this meta-analysis to verify the association between the PSCA rs2294008 (C/T) polymorphism and cancer risk. Methods: A systematic literature search was performed using PubMed, EMBASE, and the Chinese National Knowledge Infrastructure, through October 20, 2022 according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association between the PSCA rs2294008 (C/T) polymorphism and cancer risk. In addition, we explored PSCA mRNA expression in cancers through online databases. Results: In total, 45 articles met our inclusion criteria and were analyzed, including 37,586 cancer cases and 51,197 non-cancer controls. Except in the recessive model, the pooled effect indicated the PSCA rs2294008 T allele was associated with an increased overall cancer risk (T vs. C: OR = 1.120, 95% CI = 1.056-1.188, p < 0.01; TT vs. CC: OR = 1.206, 95% CI = 1.066-1.364, p = 0.03; CT vs. CC: OR = 1.249, 95% CI = 1.151-1.356, p < 0.01; [CT+TT] vs. CC: OR = 1.248, 95% CI = 1.147-1.359, p < 0.01; TT vs. [CT+CC]: OR = 1.051, 95% CI = 0.954-1.156, p = 0.314). In the subgroup analysis, there were significant associations between the rs2294008 T allele and increased risk of bladder and gastric cancer. Two different online tools were used to explore the PSCA mRNA levels in cancer and the corresponding normal adjacent tissues. We found that expression of PSCA was significantly lower in gastric cancer patients. Conclusions: The PSCA rs2294008 T polymorphism is related to increased cancer susceptibility, especially for gastric and bladder cancers. This polymorphism results in a decreased PSCA expression level in gastric cancer.

The role of single-nucleotide polymorphisms of the 8q24 chromosome region in patients with concomitant bladder and prostate cancer

OBJECTIVE

To assess whether single-nucleotide polymorphisms (SNPs) of the 8q24 chromosome region are associated with recurrence-free survival (RFS) after radical cystoprostatectomy (RC) in patients with concomitant bladder (BC) and prostate cancer (PC).

MATERIALS AND METHODS

A cohort of thirty-six patients treated with RC and pelvic lymph node dissection and histologically exhibited invasive BC and incidental PC. Using Sanger sequencing, a total of seven SNPs in the androgen-responsive element of the promoter region of the following genes were assessed in tumor-free lymph nodes and correlated with oncological outcomes: PSCA (rs2294008, rs2978974, rs1045531, rs3736001), MYC (rs6983267), FXBO32 (rs7830622), and MIR151A (rs14974929). The median follow-up was 26 months (range: 4-68).

RESULTS

In a dominant model, patients exhibiting rs2978974 as a minor allelic variant of the PSCA gene had worse RFS (32 vs. 75%, p = 0.015). No associations were found for the other SNPs.

CONCLUSIONS

These data suggest that the rs2978974 of the PSCA gene correlates with inferior BC-specific RFS after RC and should be further evaluated in larger studies.

Evaluation of 17 genetic variants in association with leukemia in the north Indian population using MassARRAY Sequenom

Leukemia is a heterogeneous disorder, characterized by elevated proliferation of white blood cells. In this study, we explored the association of 17 genetic variants with leukemia patients in the Jammu and Kashmir region of north India. The variants were genotyped by using a high-throughput Agena MassARRAY platform in 758 individuals (166 cases and 592 controls). Of the 17 single-nucleotide polymorphisms (SNPs) studied, five SNPs were showing significant association with the high risk of leukemia in the north Indian population, which includes rs10069690 of telomere reverse transcriptase (TERT) with OR = 0.34 (95% CI, 0.20-0.58; p = .0008), rs2972392 (​​​PSCA) with OR 1.86 (95% CI, 1.04-3.81; p = .035), rs4986764 (BRIP1) with OR 1.34 (95% CI, 1.00-1.80; p = .04), rs6990097 (TNKS) with OR 1.81 (95% CI, 1.2-2.6; p = .001) and rs12190287 (TCF21) with OR 2.87 (95% CI, 1.72-4.7; p = .0001) by allelic association using Plink and analyzed by SPSS. This is the first study to explore these variants with leukemia in the studied population.

PSCA, Cox-2, and Ki-67 are independent, predictive markers of biochemical recurrence in clinically localized prostate cancer: a retrospective study

Prostate cancer is the second most common male cancer, with half of all patients going on to develop metastases. To better identify patients at high risk for prostate cancer progression and reduce prostate cancer-related mortality, improved prognostic factors are required. In this study, we used immunohistochemistry (IHC) to determine the prognostic values of multiple tissue biomarkers in hormone-naοve prostatectomy specimens of prostate cancer. Using 510 prostatectomy specimens collected between 2002 and 2012, IHC analysis was performed for Cerb-2, Cyclin D1, VEGF, EGFR, Rb, PSCA, p53, Bcl-2, Cox-2, PMS2, and Ki-67 on formalin-fixed paraffin-embedded sections. The Cox proportional hazard model was used to determine the predictive risk factors for biochemical recurrence (BCR) of prostate cancer. During a median 44-month follow-up, 128 (25.1%) patients developed BCR. A multivariate regression analysis revealed that Ki-67 (hazard ratio [HR]: 1.60, P = 0.033), PSCA (HR: 0.42, P < 0.001), and Cox-2 (HR: 2.05, P = 0.003) were the only significant prognostic tissue markers of BCR. Resection margin status (HR: 1.67, P = 0.010), pathologic pT0/1/2 stage (vs pT3/4; HR: 0.20, P = 0.002), preoperative PSA levels (HR: 1.03, P < 0.001), biopsied (HR: 1.30, P = 0.022) and pathologic (HR: 1.42, P = 0.005) Gleason scores, and prostate size (HR: 0.97, P = 0.003) were significant clinicopathologic factors. The expression of Ki-67, PSCA, and Cox-2 biomarkers along with other clinicopathologic factors were prognostic factors for BCR in patients with clinically localized prostate cancer following radical prostatectomy.

PSCA rs1045531 Polymorphism and the Risk of Prostate Cancer in a Chinese Population Undergoing Prostate Biopsy

Background and Purpose:

This study explored the association between a single-nucleotide polymorphism of prostate stem cell antigen and prostate cancer in Chinese patients undergoing prostate biopsy.

Materials and Methods:

DNA from 416 patients undergoing prostate biopsy was typed for the prostate stem cell antigen rs1045531 single-nucleotide polymorphism. The frequency of the rs1045531 polymorphism in patients with prostate cancer and in patients with benign prostatic hyperplasia was compared. Associations between the polymorphism and the risk of prostate cancer, prostate special antigen, Gleason score, and clinical stage were analyzed.

Results:

Statistically significant differences in the distribution of the rs1045531 genotypes and alleles were found between prostate cancer and benign prostatic hyperplasia in patients undergoing prostate biopsy (P = .035 and .046, respectively). We found that the rs1045531 AC genotype was significantly associated with a high risk of prostate cancer in the heterozygote model (AC vs CC; odds ratio = 2.383, 95% confidence interval: 1.198-4.741, χ² = 6.229, P = .013) and the dominant model (AA/AC vs CC; odds ratio = 2.169, 95% confidence interval: 1.112-4.229, χ² = 5.228, P = .022). However, susceptibility of prostate cancer was decreased in the homozygote model (AA vs CC; odds ratio = 0.828, 95% confidence interval: 0.143-4.805, P = .601). When considering clinical factors, the rs1045531 showed an association with prostate special antigen of 10 ng/mL or greater, a Gleason score of 7 or greater, and a size of T2 or greater.

Conclusion:

Men with the rs1045531 AC genotype of prostate stem cell antigen were at higher risk of prostate cancer in Chinese patients undergoing prostate biopsy.

Association between PSCA gene polymorphisms and the risk of cancer: an updated meta-analysis and trial sequential analysis

Previous studies have investigated the relationships between PSCA rs2294008 C>T and rs2976392 G>A polymorphisms and cancer susceptibility. However, the available findings remained inconsistent and even controversial. Thus, the aim of this meta-analysis was performed to clarify such associations. The online databases PubMed, EMBASE and Web of Science searched for relevant studies, covering all the papers published until September 1st, 2016. Data were pooled by odds ratios (ORs) with 95% confidence intervals (CIs) to evaluate the strength of such associations. Then, trial sequential analysis was performed to estimate whether the evidence of the results was firm. Overall, a significant increased risk of cancer was associated with PSCA rs2294008 C>T and rs2976392 G>A polymorphisms. For the PSCA rs2294008 polymorphism, when stratified by type of cancer, the results were significant especially in gastric cancer and bladder cancer. Moreover, in the subgroup analysis by ethnicity, significant results were detected in both Asian and Caucasian populations. Similarly, for the PSCA rs2976392 polymorphism, the stratification analyses by type of cancer showed that the results were significant only in gastric cancer. In addition, the stratification analyses by ethnicity detected that this polymorphism increased cancer risk only in Asian populations. Then, trial sequential analyses demonstrated that the results of the meta-analysis were based on sufficient evidence. Therefore, this meta-analysis suggested that the PSCA rs2294008 C>T and rs2976392 G>A polymorphisms might be associated with cancer susceptibility, which might act as a potential predicted biomarker for genetic susceptibility to cancer, especially in gastric cancer and bladd er cancer.

Genetic variation of the PSCA gene (rs2294008) is not associated with the risk of prostate cancer

Prostate stem cell antigen ( PSCA ) is a cell-membrane glycoprotein consisting of 123 amino acids and highly expressed in the prostate, but there have been few reports on the relationship between rs2294008 of PSCA and prostate cancer in the literature. Therefore, we evaluated the association between rs2294008 and the risk of prostate cancer. A total of 240 prostate cancer patients and 306 controls (patients with benign prostatic hyperplasia) were enrolled. Genotype analysis of rs2294008 of PSCA was performed using PCR. Logistic regression analysis was performed according to the genotype of PSCA rs2294008. We found that CT and TT genotypes were associated with an insignificant risk of prostate cancer compared with the CC genotype ( P = 0.627 and 0.397, respectively). In addition, there was no significant difference in rs2294008 according to clinicopathological parameters, such as age, Gleason score, prostate-specific antigen (PSA), stage, and metastasis in prostate cancer ( P >0.05 for each). Age, Gleason score, PSA, pathologic stage, and metastasis did not modify the association between PSCA and the risk of prostate cancer (each P >0.05 for each). Taken together, the genetic polymorphism of PSCA rs2294008 was not associated with the risk of prostate cancer. Our results suggest that rs2294008 may not play a role in prostate carcinogenesis.

Impact of DCC (rs714) and PSCA (rs2294008 and rs2976392) Gene Polymorphism in Modulating Cancer Risk in Asian Population

Multiple studies have investigated the association of gene variant of Deleted in colorectal carcinoma (DCC) and Prostate Stem cell antigen (PSCA) with various cancer susceptibility; however, the results are discrepant. Since SNPs are emerging as promising biomarker of cancer susceptibility, here, we aimed to execute a meta-analysis of DCC (rs714 A > G) and PSCA (rs2294008 C > T, rs2976392 G > A) polymorphism to demonstrate the more accurate strength of these associations. We followed a rigorous inclusion/exclusion criteria and calculated the pooled odds ratios (ORs) and 95% confidence intervals (CIs). Overall, the pooled analysis showed that the DCC rs714 conferred increased risk of cancer only in Asians (AA vs. GG: OR = 1.86, p ≤ 0.0001; AG vs. GG: OR = 1.43, p = 0.005; GA + AA vs. GG: OR = 1.66, p ≤ 0.0001; AA vs. GG + GA; OR = 1.52, p ≤ 0.004, A vs. G allele: OR = 1.41, p ≤ 0.0001). PSCA rs2294008 was associated with increased overall cancer risk (TT vs. CC: OR = 1.28, p = 0.002; CT vs. CC: OR = 1.21, p ≤ 0.0001; CT + TT vs. CC: OR = 1.24, p ≤ 0.0001; TT vs. CC + CT; OR = 1.17, p ≤ 0.005, T vs. C allele: OR = 1.16, p ≤ 0.0001); however, in stratified analysis this association was limited only to gastric and bladder cancer and the strength was more prominent in Asians. In contrast, the PSCA rs2976392 SNP did not modulate the cancer risk. Therefore, we concluded that rs714 and rs2294008 polymorphism may represent a potential genetic biomarker for cancer risk in Asians and gastric as well as bladder cancer, respectively. However, since our study is limited to Asians and cancer types, further larger studies involving other cancers and/or population, gene-environment interactions and the mechanism of DCC and PSCA gene deregulation are desired to define the role of genotype with overall cancer risk.

PSCA s2294008 C>T and rs2976392 G>A polymorphisms contribute to cancer susceptibility: evidence from published studies

PSCA gene plays an important role in cell adhesion, proliferation and survival. Increasing studies have focused on the association of PSCA gene rs2294008 C>T and rs2976392 G>A with cancer risk. However, the conclusions were inconsistent. Therefore, we performed a meta-analysis to elucidate whether there is a true association, or artifact. We systematically searched eligible studies from MEDLINE, EMBASE and CBM database. Odds ratios and 95% confidence intervals were used to evaluate the strength of the association. The final analysis included 32 studies consisting of 30028 cases and 38765 controls for the rs2294008 C>T polymorphism, and 14 studies with 8190 cases and 7176 controls for the rs2976392 G>A polymorphism. Consequently, the PSCA rs2294008 C>T polymorphism was significantly associated with increased overall cancer risk. Further stratifications indicated the increased risk was more pronounced for gastric (diffused type and non-gastric cardia adenocarcinoma) and bladder cancer. A similar association was observed for the rs2976392 G>A polymorphism. This meta-analysis demonstrated that both of the PSCA rs2294008 C>T and rs2976392 G>A polymorphisms are associated with increased cancer risk, especially for gastric cancer and bladder cancer. Further large-scale studies with different ethnicities and subtypes of gastric cancer are required to confirm the results from this meta-analysis.

The Influence of PSCA Gene Variation on Its Expression and Gastric Adenocarcinoma Susceptibility in the Northwest Chinese Population

Gastric adenocarcinoma (GAC) imposes a considerable health burden around the world. Gene variation in prostate stem cell antigen gene (PSCA) has been identified to be associated with GAC risk, while the results showed regional variation. To explore the influence of PSCA gene variation on its expression and GAC risk in the Northwest Chinese population, four single nucleotide polymorphisms (SNPs) of PSCA were genotyped in 476 GAC cases and 481 controls using MassARRAY system. Two SNPs of rs2294008 (C>T) and rs2976392 (G>A) were identified to be associated with GAC risk. rs2294008, rs2976392 and rs10216533 made up two statistically significant haplotypes (Hap-CGG and Hap-TAG). Additionally, PSCA expression was analyzed by quantitative real time PCR, immunohistochemistry and tissue microarray. The results showed that PSCA expression was decreased in GAC tissues compared with adjacent normal tissues. For normal tissues, PSCA expression was higher with Hap-TA than that with Hap-CG. For GAC tissues, the differentiation degree of Hap-TA was higher than that of Hap-CG. The expression distribution of PSCA in multiple human organs showed disparity. These results suggest that PSCA gene variation has a potential effect on its expression and GAC risk in the Northwest Chinese population.

Cancer screenee cohort study of the National Cancer Center in South Korea

The Cancer Screenee Cohort Study was first established in 2002 by the National Cancer Center in South Korea to investigate all possible risk factors related to cancers and to expand biological specimen banking for the development of effective methodologies for cancer detection, diagnosis, and prevention. As of July in 2014, total 41,105 participants were enrolled in this cohort. Data were collected via questionnaire, clinical examination, cancer screening, and biological specimen testing including blood, urine, and exfoliated cervical cells. The highest incidence was found to be thyroid cancer, according to a nested case-control study that was linked to the National Cancer Registry information as of December 31, 2011. Case-control, cross-sectional, and cohort studies have been published using these data since 2009. Diet and nutrition was the most published topic, followed by genetics, hepatitis B virus and liver cancer screening, methodologies, physical activity, obesity, metabolic syndrome, smoking and alcohol consumption, and blood type. Evidence from the Cancer Screenee Cohort Study is highly anticipated to reduce the burden of cancer in the Korean population and aid in the detection, diagnosis, and prevention of cancer.

Association of a common genetic variant in prostate stem cell antigen with cancer risk

INTRODUCTION

Polymorphisms in the prostate stem cell antigen (PSCA) gene have been hypothesized to increase the genetic susceptibility to cancers. The common sequence variation in PSCA rs2294008 (C>T) has been implicated in cancer risk. However, results of the relevant published studies were somewhat underpowered and controversial in general.

MATERIAL AND METHODS

To evaluate the role of PSCA rs2294008 (C>T) genotype in global cancer, we performed a pooled analysis of all the available published studies involving 22,817 cancer patients and 27,753 control subjects.

RESULTS

The results showed evidence that PSCA rs2294008 (C>T) was associated with increased total cancer risk in the overall comparisons. Stratified analysis by cancer type indicated that PSCA rs2294008 T is associated with increased risk of gastric cancer (OR = 1.24, 95% CI = 1.09-1.42, p heterogeneity < 0.001, I (2) = 88.0%) and bladder cancer (OR = 1.07, 95% CI = 1.04-1.11, p heterogeneity = 0.108, I (2) = 55.0%) by allelic contrast. Furthermore, in stratified analysis by histological types of gastric cancer, this PSCA variant showed significant associations with diffuse type (OR = 1.81, 95% CI = 1.16-2.81, p heterogeneity < 0.001, I (2) = 88.9%) but not intestinal type (OR = 1.29, 95% CI = 0.95-1.74, p heterogeneity < 0.001, I (2) = 85.2%) in a dominant genetic model. Similar results were found in Asian and European descendents and population-based studies.

CONCLUSIONS

In all, our meta-analysis suggests that PSCA rs2294008 (C>T) may play allele-specific roles in cancer development. Further prospective studies with larger numbers of participants worldwide should be performed in different kinds of cancer and other descendents in more detail.

Genetic variations of α -methylacyl-CoA racemase are associated with sporadic prostate cancer risk in ethnically homogenous Koreans

Background. To assess if the variants of (R)-alpha-methyl-CoA racemase (AMACR) gene would be associated with the risk of sporadic prostate cancer in ethnically homogenous Koreans. Materials and Methods. We enrolled 194 patients with prostate cancer and 169 healthy controls. A total of 17 single nucleotide polymorphisms of the AMACR gene were selected. The distribution of each genotype and haplotype was analyzed and their association with the incidence of prostate cancer was evaluated. Further, we detected AMACR expression in tumor with immunohistochemistry and analyzed its association with genotype regarding prostate cancer risk. Results. AG or GG genotype of rs2278008 (E277K) tended to lower prostate cancer risk. The minor G allele was found to be a significant allele that decreased the risk of prostate cancer (adjusted OR, 0.57; 95% CI, 0.35–0.93, P value = 0.025). In patients expression AMACR, AG or GG genotype was also significant genotype in terms of prostate cancer risk (adjusted OR, 0.47; 95% CI, 0.26–0.87, P value = 0.017). Further, [GGCGG] haplotype consisted of five coding SNPs of rs2278008, rs34677, rs2287939, rs10941112, and rs3195676 which decreased the risk of prostate cancer (P value = 0.047). Conclusions. Genetic variations of AMACR are associated with the risk of sporadic prostate cancer that underwent radical prostatectomy in Koreans.

Prostate stem cell antigen polymorphisms and susceptibility to gastric cancer: a systematic review and meta-analysis

BACKGROUND

Many studies have reported that prostate stem cell antigen (PSCA) polymorphisms (rs2294008 and/or 2976392) are significantly associated with gastric cancer (GC) risk, although the published results are inconsistent. We conducted a systematic review and meta-analysis for relevant literatures to quantitatively evaluate the relationship between PSCA polymorphisms and GC susceptibility.

METHODS

Extensive searches were conducted in three databases up to November 1, 2011. ORs and 95% CIs were used to assess the strength of the associations. The data were further stratified by ethnicity, histopathology, subsite, and study design. All of the associations were evaluated with dominant model and recessive model, respectively. Heterogeneity and publication bias were also assessed by Q test, I(2), and funnel plot accordingly.

RESULTS

Nine articles including 11 case-control data sets were included, with 10,746 GC cases and 9,158 controls for rs2294008 and 6,060 cases and 4,824 controls for rs2976392. The results showed that risk allele carriers were significantly associated with GC risk compared with nonrisk allele homozygotes. In stratification analyses, these associations remained significant for majority of subgroups except for Caucasians and noncardia tumor in dominant model, and cardia tumor in both dominant and recessive model. Random model was used when heterogeneity among studies was detected. No publication bias was observed.

CONCLUSIONS

The two loci of PSCA (rs2294008 and rs2976392) were both significantly associated with GC susceptibility and in linkage disequilibrium.

IMPACT

More prospective studies on PSCA polymorphisms at multicenters with sufficient sample size and less heterogeneity will be needed for further validations.