Lack of evidence of HPV etiology of prostate cancer following radical surgery and higher frequency of the Arg/Pro genotype in turkish men with prostate cancer

ABSTRACT Objectives The aim of this study was to assess the possible role of HPV in the development of prostate cancer (PCa) and investigate the distribution of the p53 codon 72 polymorphism in PCa in a Turkish population. Materials and methods A total of 96 tissues, which had been obtained using a radical surgery method, formalin-fixed and parafin-embedded, were used in this study. The study group consisted of 60 PCa tissues (open radical prostatectomy) and the control group contained 36 benign prostatic hyperplasia tissues (BPH) (transvesical open prostatectomy). The presence of HPV and the p53 codon 72 polymorphism was investigated in both groups using real-time PCR and pyrosequencing. Results The results of the real-time PCR showed no HPV DNA in any of the 36 BPH tissue samples. HPV-DNA was positive in only 1 of the 60 PCa samples (1.7%). The HPV type of this sample was identified as HPV-57. The distribution of the three genotypes, Arg/Arg, Arg/Pro and Pro/Pro was found to be 45.6, 45.6, and 8.8% in the PCa group and 57.1%, 34.3% and 8.6% in the control group, respectively. Compared with the control group, patients with PCa had a higher frequency of the Arg/Pro genotype and Proline allele (odds ratio (OR)=1.67, 95% confidence interval (CI)=0.68-4.09, p=0.044; OR=1.13, 95% CI=0.76-1.68, p=0.021, respectively). Conclusions The results of the study do not support the hyphothesis that prostate cancer is associated with HPV infection but indicated that Proline allele can be a risk factor in the development of PCa in the Turkish population.

Partial association of restriction polymorphism of the ligand binding domain of human androgen receptor in prostate cancer

Background: Human androgen receptor [AR] functions as a steroid-hormone activated transcription factor. The receptor binds to its ligand [testosterone or dihydrotestosterone] and is translocated to the nucleus to stimulate the transcription of androgen responsive genes. Mutations in the ligand binding domain [LBD] impair the receptor activity and play a crucial role in the development and progression of prostate cancer [PCa]

Materials and methods: This work was designated to investigate the restriction integrity of the LBD and its association with benign prostatic hyperplasia [BPH] and prostate cancer. Exons of this domain [exons: 4-8] were amplified from prostate tissue of BPH and PCa patients and the restriction polymorphism was investigated by SmlI, HphI and Tsp45I restriction enzymes in both BPH and PCa groups

Results: Data revealed the integrity of exons 4-6 in both BPH and PCa patients. Exons 7 and 8, however have kept their constitutional pattern only in BPH patients. Hph1 site showed an abnormal restriction pattern in 40% and 26.7% of PCa patients. Also, Tsp45I demonstrated restriction polymorphism in 20% and 13% of PCa patients

Conclusion:Our results indicate that the loss of the restriction integrity in the C-terminal part [exons: 7 and 8] of the LBD is associated with the progression of benign prostatic hyperplasia to prostate cancer

Androgen receptor CAG polymorphism and the risk of benign prostatic hyperplasia in a Brazilian population

Benign prostatic hyperplasia (BPH) is a very frequent age-related proliferative abnormality in men. Polymorphic CAG repeat in the androgen receptor (AR) can alter transactivation of androgen-responsive genes and potentially influence BPH risk. We investigated the association between CAG repeat length and risk of BPH in a case-control study of a Brazilian population. We evaluated 214 patients; 126 with BPH and 88 healthy controls. DNA was extracted from peripheral leucocytes and the AR gene was analyzed using fragment analysis. Hazard ratio (HR) and 95% confidence interval were estimated using logistic regression models. Mean CAG length was not different between patients with BPH and controls. The CAG repeat length was examined as a categorical variable (CAG < 21 vs. CAG > 21 and CAG < 22 vs. CAG > 22) and did not differ between the control vs. the BPH group. We found no evidence for an association between AR CAG repeat length in BPH risk in a population-based sample of Brazilians.

Underexpression of MMP-2 and its regulators, TIMP2, MT1-MMP and IL-8, is associated with prostate cancer

OBJECTIVE: Extracellular matrix homeostasis is strictly maintained by a coordinated balance between the expression of metalloproteinases (MMPs) and their regulators. The purpose of this study was to investigate whether MMP-2 and its specific regulators, TIMP-2, MT1-MMP and IL-8, are expressed in a reproducible, specific pattern and if the profiles are related to prognosis and clinical outcome of prostate cancer (PCa). MATERIALS AND METHODS: MMP-2, TIMP-2, MT1-MMP and IL-8 expression levels were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) in freshly frozen malignant and benign tissue specimens collected from 79 patients with clinically localized PCa who underwent radical prostatectomies. The control group consisted of 11 patients with benign prostate hyperplasia (BPH). The expression profile of the MMP-2 and its regulators were compared using Gleason scores, pathological stage, pre-operative PSA levels and the final outcome of the PCa. RESULTS: The analysis of 79 specimens of PCa revealed that MMP-2, TIMP-2, MT1-MMP and IL-8 were underexpressed at 60.0%, 72.2%, 62.0% and 65.8%, respectively, in malignant prostatic tissue in relation to BPH samples. Considering the prognostic parameters, we demonstrated that high Gleason score tumors (> 7) overexpressed MMP-2 (p = 0.048) and TIMP-2 (p = 0.021), compared to low Gleason score tumors (< 7). CONCLUSION: We have demonstrated that MMP-2 and its regulators are underexpressed in PCa. Alternatively, overexpression of MMP-2 and TIMP-2 was related to higher Gleason score tumors. We postulate that alterations in metalloproteinase expression may be important in the control of tissue homeostasis related to prostate carcinogenesis and tumor behavior.

Association of IL10, IL10RA, and IL10RB Polymorphisms with Benign Prostate Hyperplasia in Korean Population

Cytokines such as interleukin 10 (IL10) may play an important role in the process of inflammation. The aim of this study was to analyze the association between IL10, IL10RA and IL10RB single nucleotide polymorphisms (SNPs), and benign prostate hyperplasia (BPH) in Korean population. All patients with BPH were divided into two groups according to international porostate symptom score (IPSS), prostate specific antigen (PSA) level, Qmax, and prostate volume. We selected two IL10 SNPs (rs1518111 and rs1554286), three IL10RA SNPs (rs2256111, rs4252243, and rs2228054), and two IL10RB SNPs (rs999788 and rs2834167). Genotypes of seven SNPs were determined through direct sequencing. The G/G genotype of IL10RB polymorphism (rs2834167) was associated with a high PSA level compared with the A/G + A/A genotypes (P = 0.009). Of IL10 SNP, the A/A genotype of rs1518111 and T/T genotype of rs1554286 were associated with small prostate volume, respectively (P = 0.011, P = 0.014). Moreover, the T/T genotype of IL10RB polymorphism (rs999788) was associated with high prostatic volume compared with the T/C + C/C genotypes (P = 0.033). The linkage disequilibrium (LD) blocks were formed in IL10 and IL10RA. However, haplotypes in the LD block were not associated with BPH. It is concluded that there is a strong association between the IL10 and IL10RB SNPs, and BPH in Korean population.

Incidência de mutação no códon 12 do protoncogene K-ras em carcinoma de próstata humana em uma amostra da população brasileira / The incidence of mutation in codon 12 of the k-ras proto-oncogene in human prostate carcinoma with a Brazilian population sample

Com o intuito de estudar a participação do gene ras ativado na tumorigênese humana, pesquisamos a freqüência de mutação pontual no códon 12 do gene K-ras em espécimes cirúrgicos de pacientes portadores de câncer de próstata. Foi utilizado um grupo controle de pacientes com hiperplasia prostática benigna (HPB). Os cortes destinados ao estudo foram submetidos a extração do DNA pelo método da proteinase K. A amplificação do fragmento isolado foi obtida pela reação em cadeia de polimerase seguida por clivagem, utilizando-se a enzima de restrição Mval. A eletroforese em gel de agarose permitiu a verificação da presença de mutações. Constatamos a presença de mutação no códon 12 do gene K-ras em dois dos 15 carcinomas de próstata estudados (13,3 por cento), sendo que nenhuma em pacientes com HPB. A ocorrência de mutação de 13,3 por cento na amostra da população brasileira analisada caracteriza uma incidência intermediária entre as populações japonesa e americana. É pouco provável que a mutação isolada do K-ras seja um evento significativo na carcinogênese prostática nesta população.