p53 Pro72Arg polymorphism and prostate cancer in men of African descent

Genetic and biological drivers of prostate cancer disparities in Black men

Black men with prostate cancer have historically had worse outcomes than white men with prostate cancer. The causes of this disparity in outcomes are multi-factorial, but a potential basis is that prostate cancers in Black men are biologically distinct from prostate cancers in white men. Evidence suggests that genetic and ancestral factors, molecular pathways involving androgen and non-androgen receptor signalling, inflammation, epigenetics, the tumour microenvironment and tumour metabolism are contributing factors to the racial disparities observed. Key genetic and molecular pathways linked to prostate cancer risk and aggressiveness have potential clinical relevance. Describing biological drivers of prostate cancer disparities could inform efforts to improve outcomes for Black men with prostate cancer.

Association of TP53 gene polymorphisms with the risk of acute lymphoblastic leukemia in Moroccan children

BACKGROUND

TP53 gene plays a pivotal role in maintaining genetic stability and prevention of malignancies. Alterations of this gene are implicated in more than half of human cancers. To the best of our knowledge, this study is the first to explore TP53 polymorphisms in Moroccan childhood acute lymphoblastic leukemia (ALL).

METHODS AND RESULTS

DNA samples of 45 ALL children were obtained from peripheral blood. A total of 333 healthy Moroccans were used as controls. Polymerase chain reaction and Sanger sequencing were performed to analyze TP53 hotspot exons in cases. We identified a significant protective effect of the TP53-Arg variant at rs1042522 [OR 0.4593 (0.249-0.8472), p = 0.0127] and the Pro/Arg genotype [OR 0.0350 (0.0047-0.2583), p = 0.0010]. Additionally, we found a novel association between the C-allele of Arg213Arg 1800372 [OR 2.7736 (1.3821-5.5664), p = 0.0041] and the risk of childhood ALL. Importantly, TC/CC genotypes of this polymorphism were revealed to enhance the risk of ALL among females [OR 9.0 (3.1555-25.6693), p < 0.0001]. Arg213Arg was also noticed to be associated with the hemoglobin count of patients at diagnosis by linear regression (p = 0.0318). The analysis of penetrance showed a significant association of the CG/GG genotypes at rs1042522 and TC/CC genotypes at rs1800372 to childhood ALL via dominant model [OR 0.2090 (0.09074-0.4814), p = 0.0002 and OR 3.4205 (1.6084-7.2742), p = 0.0014 for rs1042522 and rs1800372 respectively]. No association was found between TP53 polymorphisms and patients survival.

CONCLUSION

Altogether, our findings indicated that TP53 polymorphisms are significantly involved in the genetic susceptibility to childhood ALL in Morocco.

Intronic TP53 Polymorphisms Are Associated with Increased Δ133TP53 Transcript, Immune Infiltration and Cancer Risk

We investigated the influence of selected TP53 SNPs in exon 4 and intron 4 on cancer risk, clinicopathological features and expression of TP53 isoforms. The intron 4 SNPs were significantly over-represented in cohorts of mixed cancers compared to three ethnically matched controls, suggesting they confer increased cancer risk. Further analysis showed that heterozygosity at rs1042522(GC) and either of the two intronic SNPs rs9895829(TC) and rs2909430(AG) confer a 2.34-5.35-fold greater risk of developing cancer. These SNP combinations were found to be associated with shorter patient survival for glioblastoma and prostate cancer. Additionally, these SNPs were associated with tumor-promoting inflammation as evidenced by high levels of infiltrating immune cells and expression of the Δ133TP53 and TP53β transcripts. We propose that these SNP combinations allow increased expression of the Δ133p53 isoforms to promote the recruitment of immune cells that create an immunosuppressive environment leading to cancer progression.

Polymorphism of glutathione S-transferase in the population of Polish patients with carcinoma of the prostate

The aim of the study was frequency analysis of GSTM1, GSTT1, and GSTP1 polymorphisms of glutathione S-transferase in the group of patients with prostate cancer and in a control group of healthy individuals. Genomic DNA was isolated; molecular analysis of glutathione S-transferase M1 and T2 polymorphisms was performed using multiplex PCR and RFLP methods. The products of the PCR reaction were then visualized in agarose gel, and a statistical analysis of the results was performed. No statistically significant differences were found in the frequency of glutathione S-transferase polymorphisms between 66 patients with prostate cancer and the control group (64 healthy volunteers). The GSTM1 gene deletion was found in ca. 47% of patients with prostate cancer and in ca. 55% of the controls. The GSTT1 deletion was found in approximately 17% of patients and 14% of the controls. The distribution of GSTP1 Ile/Ile, Ile/Val, and Val/Val polymorphisms was ca. 51.5%, 39%, and 9% in the group of patients and 61%, 34%, and 5% in the control group, respectively. The results indicate that there is no relationship between glutathione S-transferase polymorphisms and prostate cancer in the study group, which is a novelty when compared with the previous work on the role of these genetic variants in the etiology of cancer.

Association between TP53 gene codon72 polymorphism and prostate cancer risk: A systematic review and meta-analysis

BACKGROUND

TP53 gene polymorphism could increase risks of several kinds of cancer. But it remained controversial whether TP53 gene codon72 polymorphism was associated with the susceptibility to prostate cancer. Thus, we conducted a meta-analysis that evaluated the association between TP53 gene codon72 polymorphism and prostate cancer risk.

METHOD

A comprehensive research was performed from PubMed, Embase, Web of Science and China National Knowledge Infrastructure (CNKI) up to December 31, 2018. A random effect model was used to evaluate the effect of the outcome. The statistical analyses were performed with Review Manager 5.3.0 and Stata 14.0. The sensitivity analysis and publication bias tests were also performed to confirm the reliability of this meta-analysis.

RESULTS

22 studies included 3146 cases and 4010 controls were involved in this meta-analysis. Overall, no association was observed between TP53 gene codon72 polymorphism and prostate cancer risk (Arg vs Pro: odds ratio [OR] = 1.12, 95% confidence interval [CI] = 0.98-1.30; ArgArg vs ProPro: OR = 1.26, 95% CI = 0.90-1.75; ProPro vs ArgArg+ ArgPro: OR = 1.17, 95% CI = 0.86-1.57; ArgPro+ ProPro vs ArgArg: OR = 1.21, 95% CI = 0.97-1.51). Subgroup analyses, based on ethnicity, source of control and Hardy-Weinberg equilibrium (HWE) status, showed consistent results.

CONCLUSION

The meta-analysis we performed showed that there was no association of TP53 gene codon72 polymorphism with prostate cancer risk.

Technical Feasibility of Tissue Microarray (TMA) Analysis of Tumor-Associated Immune Response in Prostate Cancer

Introduction: The androgen receptor (AR) regulates immune-related epithelial-to-mesenchymal transition (EMT), and prostate cancer (PCa) metastasis. Primary tumor-infiltrating lymphocytes (TILs) [CD3⁺, CD4⁺, and CD8⁺ TILs] are potential prognostic indicators in PCa, and variations may contribute to racial disparities in tumor biology and PCa outcomes.

Aim: To assess the technical feasibility of tumor microarray (TMA)-based methods to perform multi-marker TIL profiling in primary resected PCa.

Methods: Paraffin-embedded tissue cores of histopathologically-confirmed primary PCa (n = 40; 1 TMA tissue specimen loss) were arrayed in triplicate on TMAs. Expression profiles of AR, CD3⁺, CD4⁺, and CD8⁺ TILs in normal prostate, and the center and periphery of both the tumor-dominant nodule and highest Gleason grade were detected by IHC and associated with clinical and pathological data using standard statistical methodology. An independent pathologist, blinded to the clinical data, scored all samples (percent and intensity of positive cells).

Results: TMAs were constructed from 21 (53.8%) Black and 18 (46.2%) White males with completely-resected, primarily pT2 stage PCa [pT2a (n = 3; 7.7%); pT2b (n = 2; 5.1%); pT2c (n = 27; 69.2%); pT3a (n = 5; 12.8%); mean pre-op PSA = 8.17 ng/ml]. The CD3, CD4, CD8, and CD8/CD3 cellular protein expression differed from normal in the periphery of the dominant nodule, the center of the highest Gleason grade, and the periphery of the highest Gleason grade (P < 0.05). Correlations between TIL expression in the center and periphery of the dominant nodule, with corresponding center and periphery of the highest Gleason grade, respectively, were robust, and the magnitude of these correlations differed markedly by race (P < 0.05).

Conclusions: Multi-marker (AR, CD3, CD4, CD8) profiling with IHC analysis of TMAs consisting of primary, non-metastatic resected prostate cancer is technically feasible in this pilot study. Future studies will evaluate primary tumor immunoscore using semi-quantitative, IHC-based methodology to assess differences in the spectrum, quantity, and/or localization of TILs, and to gain insights into racial disparities in PCa tumor biology and clinical outcomes.

MDM2 and P53 polymorphisms contribute together to the risk and survival of prostate cancer

The p53 gene and MDM2 gene play critical roles in cell cycle arrest and apoptosis together. Here, we evaluated the associations of prostate cancer risk and survival with the joint effects of mdm2 and p53 polymorphisms. Totally 1,193 cases and 1,310 age frequency-matched controls were included in the study. Prostate cancer patients were followed to determine the intervals of overall survival and disease-free survival. The Pro⁷²Arg Pro allele (homozygous and heterozygous) were significantly associated with prostate cancer risk with an odds ratio (OR) of 0.77 [95% confidence interval(CI), 0.64-0.93]. SNP309 T alleles were associated with a significantly decreased prostate cancer risk among Pro⁷²Arg Pro alleles carriers (OR=0.79, 95% CI, 0.64-0.98). In addition, comparedwith the Pro⁷²Arg Pro alleles and SNP309 G homozygous, patients carrying both SNP309 T alleles and Pro⁷²Arg Arg homozygous had more favorable disease-free survival (hazard ratio [HR] = 0.59, 95% CI, 0.38-0.93). Our results indicated that SNP309 and Pro⁷²Arg polymorphisms may jointly contributeto the etiology and prognosis of prostate cancer.

Genomic comparison of early-passage conditionally reprogrammed breast cancer cells to their corresponding primary tumors

Conditionally reprogrammed cells (CRCs) are epithelial cells that are directly isolated from patients' specimens and propagated in vitro with feeder cells and a Rho kinase inhibitor. A number of these cells have been generated from biopsies of breast cancer patients, including ductal carcinoma in situ and invasive carcinomas. The characterization of their genomic signatures is essential to determine their ability to reflect the natural biology of their tumors of origin. In this study, we performed the genomic characterization of six newly established invasive breast cancer CRC cultures in comparison to the original patients' primary breast tumors (PBT) from which they derived. The CRCs and corresponding PBTs were simultaneously profiled by genome-wide array-CGH, targeted next generation sequencing and global miRNA expression to determine their molecular similarities in the patterns of copy number alterations (CNAs), gene mutations and miRNA expression levels, respectively. The CRCs' epithelial cells content and ploidy levels were also evaluated by flow cytometry. A similar level of CNAs was observed in the pairs of CRCs/PBTs analyzed by array-CGH, with >95% of overlap for the most frequently affected cytobands. Consistently, targeted next generation sequencing analysis showed the retention of specific somatic variants in the CRCs as present in their original PBTs. Global miRNA profiling closely clustered the CRCs with their PBTs (Pearson Correlation, ANOVA paired test, P<0.05), indicating also similarity at the miRNA expression level; the retention of tumor-specific alterations in a subset of miRNAs in the CRCs was further confirmed by qRT-PCR. These data demonstrated that the human breast cancer CRCs of this study maintained at early passages the overall copy number, gene mutations and miRNA expression patterns of their original tumors. The further characterization of these cells by other molecular and cellular phenotypes at late cell passages, are required to further expand their use as a unique and representative ex-vivo tumor model for basic science and translational breast cancer studies.

Association between the rs1042522 polymorphism in TP53 and prostate cancer risk: An updated meta-analysis

Objective

The proposal of the present study was to investigate whether the TP53 rs1042522 polymorphism confers susceptibility to prostate cancer (PCa), by performing an updated meta-analysis.

Methods

Eligible publications investigating the association between the TP53 rs1042522 polymorphism and PCa susceptibility were selected from PubMed, Google Scholar, and Web of Science. We used STATA 12.0 software to conduct the analyses. Odds ratio (OR) with 95% confidence interval (CI) was calculated.

Results

A total of 17 case–control studies were retrieved reporting a total of 2683 cases and 2981 controls. However, no significant association was uncovered between the TP53 rs1042522 polymorphism and PCa susceptibility in the overall population under the five genetic models. In the stratification analysis by source of control, an increased susceptibility to PCa was identified in the population-based (P-B) group (CG vs. GG: OR = 1.48, 95% CI: 1.24–1.77, P < 0.01; CC/CG vs. GG: OR = 1.32, 95% CI: 1.12–1.57, P < 0.01), whereas a decreased susceptibility was uncovered in the hospital-based (H-B) group (CG vs. GG: OR = 0.67, 95% CI: 0.46–0.96, P = 0.03; CC/CG vs. GG: OR = 0.67, 95% CI: 0.46–0.99, P = 0.04) under heterozygous and dominant model.

Conclusion

This study did not find an association between the TP53 rs1042522 polymorphism and PCa susceptibility in the overall population and corresponding subgroup analyses except in the stratification analysis by source of control. The results suggest that the TP53 rs1042522 polymorphism is not a risk factor for PCa.

Association of the rs1042522 polymorphism with increased risk of prostate adenocarcinoma in the Pakistani population and its HuGE review

Prostate adenocarcinoma is one of the leading causes of cancer related mortality in men but still limited knowledge is available about its associated functional SNPs including rs1042522 (Pro72Arg). The present study was undertaken to explore the association of this SNP with susceptibility to prostate adenocarcinoma along with its structural and functional impacts in the Pakistani population in a case-control study. Three-dimensional structure of human TP53 with Pro72Arg polymorphism was predicted through homology modeling, refined and validated for detailed structure-based assessment. We also carried out a HuGE review of the previous available data for this polymorphism. Different genetic models were used to evaluate the genotypes association with the increased risk of PCa (Allelic contrast: OR=0.0.34, 95%CI 0.24-0.50, p=0.000; GG vs CC: OR=0.17, 95%CI 0.08-0.38, p=0.000; Homozygous: OR=0.08, 95%CI 0.04-0.15, p=0.000; GC vs CC: OR=2.14, 95%CI 1.01-4.51, p=0.046; Recessive model: OR=0.10, 95%CI 0.05-0.18, p=0.000; Log Additive: OR=3.54, 95%CI 2.13-5.89, p=0.000) except the Dominant model (OR=0.77, 95%CI 0.39-1.52, p=0.46). Structure and functional analysis revealed that the SNP in the proline rich domain is responsible for interaction with HRMT1L2 and WWOX. In conclusion, it was observed that the Arg coding G allele is highly associated with increased risk of prostate adenocarcinoma in the Pakistani population (p=0.000).

Association of p53 and p21 polymorphisms with prostate cancer

Cell cycle deregulation is common in human cancer. Alterations of the tumor-suppressor gene p53 and its downstream effector p21 have been indicated in the development of numerous human malignancies. Therefore, we hypothesize that the p53 codon 72 polymorphism, either on its own or in combination with p21 (C98A and C70T) polymorphisms, modifies the risk of prostate cancer within the Slovak population, and no previous studies have investigated these gene-gene interactions in the pathogenesis of prostate cancer in the Slovak population. Polymerase chain reaction-restriction fragment length polymorphism was used to determine the p53 and p21 genotypes in subjects comprising 300 prostate cancer patients and 446 healthy individuals. These 3 polymorphisms individually did not correlate with the prostate cancer risk. Conversely, the interaction between the p53 and p21 polymorphisms significantly decreased the risk of prostate cancer, with the odds ratio (OR) being 0.49 [95% confidence interval (CI), 0.27-0.86; P<0.05] for subjects carrying the p53 codon 72 arginine (Arg)/proline (Pro)+Pro/Pro and p21 C98A CA genotypes compared to the combined reference genotypes p53 codon 72 Arg/Arg and p21 C98A CC. Neither the p53 genotypes nor the p21 genotypes showed statistically significant differences in Gleason score or serum prostate-specific antigen levels (P>0.05). A decreased risk of prostate cancer association with the p21 C98A CA genotype (OR=0.58; 95% CI, 0.36-0.93; P<0.05) in non-smokers compared to the non-smokers with the p21 C98A CC genotype was observed. Smokers carrying the p53 codon 72 Pro/Pro genotype were not at any significant risk of prostate cancer (OR=2.97; 95% CI, 0.51-17.15) compared to the non-smokers with the Arg/Arg genotype. Taken together, to the best of our knowledge this is the first study to show that a combination of the variant genotypes of p53 codon 72 and p21 C98A may modify the prostate cancer risk within the Slovak population.

Evaluation of the p53 Arg72Pro polymorphism and its association with cancer risk: a HuGE review and meta-analysis

Codon 72 is a hotspot of polymorphisms in the TP53 gene, which encodes a hub protein in the protein-protein interaction network of p53. It is thus a central player in the apoptotic pathway, preventing cancer. A large number of articles have been published exploring its association with an increased susceptibility to most common cancers. However, these studies have produced inconclusive results, which may be due to their small sample sizes or study designs. To comprehensively evaluate the potential correlation between the TP53 Pro72Arg polymorphism and cancer risk and to better characterize the Pro72Arg polymorphism, we performed a systematic HuGE review and meta-analysis of candidate studies through online resources, according to the proposal of MOOSE and the PRISMA statement. The identified articles were carefully examined according to the inclusion criteria. Pooled odds ratios were calculated on the basis of different genetic models, while heterogeneity was assessed through a chi-based Q-test and I2. After applying the inclusion filters, we obtained a pool of 54 eligible studies, representing 18 718 cases and 21 261 controls. Overall, non-significant cancer risk was observed in all the genetic models but their observed heterogeneity was extremely significant. In subgroup analysis, an increased susceptibility was observed in the case of colorectal cancer, while in cancers of the female reproductive system, significantly increased risk was detected in all the genetic models except the dominant model. In another subgroup analysis, significantly increased cancer risk was observed among Asians in homozygous and recessive models, while in Americans increased cancer risk was observed only in dominant and recessive models. No association was observed in the rest of the populations. In conclusion, pooled subgroup analysis on the basis of ethnicity proved that the TP53 Arg72Pro polymorphism is associated with an increased risk of cancer in Asians and Americans only and is not associated in other populations. It can therefore be concluded that this meta-analysis of available data suggests partial confirmation of the association between the TP53 Arg72Pro polymorphism and cancer risk susceptibility.

No association of the p53 codon 72 polymorphism with malaria in Ghanaian primiparae and Rwandan children

The p53 protein is a key cell-signaling mediator integrating host responses to various types of stress. A common polymorphism of the encoding TP53 gene (codon 72, Pro > Arg, rs1042522) is associated with susceptibility to virus-related and other cancers. The p53 has also been shown to be central for successful Plasmodium liver stage infection. We examined whether the polymorphism is associated with P. falciparum infection in Ghanaian primiparae and Rwandan children. The allele frequency of TP53 codon 72 Arg was 0.30 among 314 Ghanaian primiparae and 0.31 among 545 Rwandan children, respectively, and it was not associated with infection prevalence or parasite density. This does not exclude p53 to be of pathophysiological relevance in malaria but argues against a major respective role of the TP53 codon 72 polymorphism.

Association of p53 codon 72 polymorphism with prostate cancer: an update meta-analysis

Many studies have been conducted to explore the association between p53 codon 72 polymorphism and prostate cancer (PCa). However, the results remain inconsistent. Therefore, we performed a large meta-analysis of relevant studies to determine a more precise estimation of this relationship. Systematic searches of the electronic databases PubMed, EMBASE, Cochrane Library, and China National Knowledge Infrastructure (CNKI) up to October 2013 were performed. Fixed or random-effects meta-analytical models were used to calculate the summary odds ratio (OR) and corresponding 95% confidence intervals (CIs). Meta-regression, Galbraith plots, subgroup analysis, and sensitivity analysis were also performed. The study included 17 case-control studies involving 2,371 PCa cases and 2,854 controls. Our results showed that the p53 codon 72 polymorphism was not associated with PCa risk in all genetic models in the overall populations. When limiting the meta-analysis to the studies conforming to Hardy-Weinberg equilibrium, the pooled analyses showed a significant association between p53 codon 72 polymorphism and PCa in a Caucasian population in co-dominant model Pro/Pro vs. Arg/Arg (OR = 1.57, 95% CI = 1.08-2.28, P = 0.017) and recessive model Pro/Pro vs. (Arg/Pro + Arg/Arg) (OR = 1.60, 95% CI = 1.12-2.27, P = 0.009). In subgroup analysis stratified by PCa stages and Gleason grades, a slight but significant association was found when advanced PCa was compared with localized PCa only in recessive model Pro/Pro vs. (Arg/Pro + Arg/Arg) (OR = 1.51, 95% CI = 1.02-2.23, P = 0.039). This meta-analysis suggested that the Pro/Pro genotype of p53 codon 72 polymorphism was associated with increased prostate cancer risk, especially among Caucasians.

Expression differences between African American and Caucasian prostate cancer tissue reveals that stroma is the site of aggressive changes

In prostate cancer, race/ethnicity is the highest risk factor after adjusting for age. African Americans have more aggressive tumors at every clinical stage of the disease, resulting in poorer prognosis and increased mortality. A major barrier to identifying crucial gene activity differences is heterogeneity, including tissue composition variation intrinsic to the histology of prostate cancer. We hypothesized that differences in gene expression in specific tissue types would reveal mechanisms involved in the racial disparities of prostate cancer. We examined 17 pairs of arrays for AAs and Caucasians that were formed by closely matching the samples based on the known tissue type composition of the tumors. Using pair-wise t-test we found significantly altered gene expression between AAs and CAs. Independently, we performed multiple linear regression analyses to associate gene expression with race considering variation in percent tumor and stroma tissue. The majority of differentially expressed genes were associated with tumor-adjacent stroma rather than tumor tissue. Extracellular matrix, integrin family and signaling mediators of the epithelial-to-mesenchymal transition (EMT) pathways were all downregulated in stroma of AAs. Using MetaCore (GeneGo) analysis, we observed that 35% of significant (p < 10(-3)) pathways identified EMT and 25% identified immune response pathways especially for interleukins-2, -4, -5, -6, -7, -10, -13, -15 and -22 as the major changes. Our studies reveal that altered immune and EMT processes in tumor-adjacent stroma may be responsible for the aggressive nature of prostate cancer in AAs.

Association between p53 Pro72Arg polymorphism and prostate cancer risk: a meta-analysis

The tumor suppressor gene p53 appears to be important in the development of many human cancers, such as prostate cancer. The association of p53 codon72 polymorphism with prostate cancer has been widely reported; however, the results are inconsistent. To derive a more precise estimation of this relationship, we performed an updated meta-analysis from 10 case-control studies. We conducted a search in the PubMed database without a language limitation, covering all papers published until July 2010. Risk ratios (RR) with 95% confidence intervals(CIs) were used to assess the strength of the association. Ten studies including 1,196 cases and 1,704 controls were selected. Overall, no significant differences of total prostate cancer risk and p53 codon polymorphism was found (Pro/Pro vs Arg/Arg, RR = 1.12, 95%CI=0.74-1.70, P_{heterogeneity} = 0.016, I² = 55.8%; Pro/Pro+Pro/Arg vs Arg/Arg, RR = 1.05, 95%CI=1.00-1.11, P_{heterogeneity} = 0.077, I² = 51.1%). In the stratified analysis by ethnicity, the same results were found. However, in the control subgroup, there was a modest decreased association between prostate cancer risk and population-based control subjects under the recessive genetic model (RR = 0.31, 95%CI=0.10-0.91, P_{heterogeneity} = 0.110, I² =60.8%). This meta-analysis suggested that p53 codon Pro72Arg polymorphism could be weakly associated with prostate cancer risk.

Multiple breast cancer cell-lines derived from a single tumor differ in their molecular characteristics and tumorigenic potential

BACKGROUND

Breast cancer cell lines are widely used tools to investigate breast cancer biology and to develop new therapies. Breast cancer tissue contains molecularly heterogeneous cell populations. Thus, it is important to understand which cell lines best represent the primary tumor and have similarly diverse phenotype. Here, we describe the development of five breast cancer cell lines from a single patient's breast cancer tissue. We characterize the molecular profiles, tumorigenicity and metastatic ability in vivo of all five cell lines and compare their responsiveness to 4-hydroxytamoxifen (4-OHT) treatment.

METHODS

Five breast cancer cell lines were derived from a single patient's primary breast cancer tissue. Expression of different antigens including HER2, estrogen receptor (ER), CK8/18, CD44 and CD24 was determined by flow cytometry, western blotting and immunohistochemistry (IHC). In addition, a Fluorescent In Situ Hybridization (FISH) assay for HER2 gene amplification and p53 genotyping was performed on all cell lines. A xenograft model in nude mice was utilized to assess the tumorigenic and metastatic abilities of the breast cancer cells.

RESULTS

We have isolated, cloned and established five new breast cancer cell lines with different tumorigenicity and metastatic abilities from a single primary breast cancer. Although all the cell lines expressed low levels of ER, their growth was estrogen-independent and all had high-levels of expression of mutated non-functional p53. The HER2 gene was rearranged in all cell lines. Low doses of 4-OHT induced proliferation of these breast cancer cell lines.

CONCLUSIONS

All five breast cancer cell lines have different antigenic expression profiles, tumorigenicity and organ specific metastatic abilities although they derive from a single tumor. None of the studied markers correlated with tumorigenic potential. These new cell lines could serve as a model for detailed genomic and proteomic analyses to identify mechanisms of organ-specific metastasis of breast cancer.

Interaction among apoptosis-associated sequence variants and joint effects on aggressive prostate cancer

Background

Molecular and epidemiological evidence demonstrate that altered gene expression and single nucleotide polymorphisms in the apoptotic pathway are linked to many cancers. Yet, few studies emphasize the interaction of variant apoptotic genes and their joint modifying effects on prostate cancer (PCA) outcomes. An exhaustive assessment of all the possible two-, three- and four-way gene-gene interactions is computationally burdensome. This statistical conundrum stems from the prohibitive amount of data needed to account for multiple hypothesis testing.

Methods

To address this issue, we systematically prioritized and evaluated individual effects and complex interactions among 172 apoptotic SNPs in relation to PCA risk and aggressive disease (i.e., Gleason score ≥ 7 and tumor stages III/IV). Single and joint modifying effects on PCA outcomes among European-American men were analyzed using statistical epistasis networks coupled with multi-factor dimensionality reduction (SEN-guided MDR). The case-control study design included 1,175 incident PCA cases and 1,111 controls from the prostate, lung, colo-rectal, and ovarian (PLCO) cancer screening trial. Moreover, a subset analysis of PCA cases consisted of 688 aggressive and 488 non-aggressive PCA cases. SNP profiles were obtained using the NCI Cancer Genetic Markers of Susceptibility (CGEMS) data portal. Main effects were assessed using logistic regression (LR) models. Prior to modeling interactions, SEN was used to pre-process our genetic data. SEN used network science to reduce our analysis from > 36 million to < 13,000 SNP interactions. Interactions were visualized, evaluated, and validated using entropy-based MDR. All parametric and non-parametric models were adjusted for age, family history of PCA, and multiple hypothesis testing.

Results

Following LR modeling, eleven and thirteen sequence variants were associated with PCA risk and aggressive disease, respectively. However, none of these markers remained significant after we adjusted for multiple comparisons. Nevertheless, we detected a modest synergistic interaction between AKT3 rs2125230-PRKCQ rs571715 and disease aggressiveness using SEN-guided MDR (p = 0.011).

Conclusions

In summary, entropy-based SEN-guided MDR facilitated the logical prioritization and evaluation of apoptotic SNPs in relation to aggressive PCA. The suggestive interaction between AKT3-PRKCQ and aggressive PCA requires further validation using independent observational studies.