Genetic variants in AR and SHBG and resistance to hormonal castration in prostate cancer

Sex hormone-binding globulin and its critical role in prostate cancer: A comprehensive review

Prostate cancer (PC) is a common and widespread cancer that affects men globally. A complicated interaction of hormonal variables influences its development. Sex hormone-binding globulin (SHBG) is a crucial element in controlling the availability of sex hormones, especially androgens, which have a notable impact on the development and progression of PC. SHBG controls the levels of free, active androgens in the body, which helps regulate androgen-dependent processes associated with PC. The equilibrium between SHBG and androgens plays a critical role in maintaining the stability of the prostate. When this balance is disrupted, it is associated with the development and advancement of PC. The processes responsible for SHBG's role in PC are complex and have multiple aspects. SHBG primarily binds to androgens, preventing them from interacting with androgen receptors (ARs) in prostate cells. It reduces the activation of androgen signaling pathways essential for tumor development and survival. In addition, SHBG can directly affect prostate cells by interacting with specific receptors on the cell surface. This review thoroughly examines the role of SHBG in PC, including its physiological activities, methods of action, and clinical consequences.

Genetic Polymorphisms and Pharmacotherapy for Prostate Cancer

The therapeutic landscape of pharmacotherapy for prostate cancer has dramatically evolved, and multiple therapeutic options have become available for prostate cancer patients. Therefore, useful biomarkers to identify suitable candidates for treatment are required to maximize the efficacy of pharmacotherapy. Genetic polymorphisms such as single-nucleotide polymorphisms (SNPs) and tandem repeats have been shown to influence the therapeutic effects of pharmacotherapy for prostate cancer patients. For example, genetic polymorphisms in the genes involved in androgen receptor signaling are reported to be associated with the therapeutic outcome of androgen-deprivation therapy as well as androgen receptor-pathway inhibitors. In addition, SNPs in genes involved in drug metabolism and efflux pumps are associated with therapeutic effects of taxane chemotherapy. Thus, genetic polymorphisms such as SNPs are promising biomarkers to realize personalized medicine. Here, we overview the current findings on the influence of genetic polymorphisms on the outcome of pharmacotherapy for prostate cancer and discuss current issues as well as future visions in this field.

Association of rs6259 polymorphism with SHBG levels and Poly Cystic Ovary Syndrome in Indian population: a case control study

Polycystic ovary syndrome (PCOS) is the most common endocrinopathy of reproductive-aged women. PCOS reflects a number of possible etiologies but its pathophysiology is still unclear. The principal abnormality of the syndrome is hyperandrogenism (70-80%). The access of androgens to target tissues is regulated by sex hormone-binding globulin (SHBG), a transport protein secreted by liver i.e. specific for androgens. Present study was done to find the association of rs6259 polymorphism with SHBG levels and Poly Cystic Ovary Syndrome in Indian population. Present study was a case control study. 400 subjects were enrolled for the study and serum SHBG levels and D327N polymorphism were measured. The D327N polymorphism (wild-type and variant allele) was detected using PCR-RFLP method (restriction enzyme Bbs-I). PCOS group was found to have significantly lower SHBG levels than healthy controls. There was no significant difference in genotype distribution between PCOS and controls (χ² = 1.0335, p = 0.59). Significant difference in SHBG levels of PCOS and control group highlights the potential of SHBG as a biomarker for PCOS. However, no significant difference in genotype distribution between PCOS and controls provided an insight that rs6259 polymorphism is not associated with the risk of PCOS and SHBG levels.

Systems Oncology: Bridging Pancreatic and Castrate Resistant Prostate Cancer

Large investments by pharmaceutical companies in the development of new antineoplastic drugs have not been resulting in adequate advances of new therapies. Despite the introduction of new methods, technologies, translational medicine and bioinformatics, the usage of collected knowledge is unsatisfactory. In this paper, using examples of pancreatic ductal adenocarcinoma (PaC) and castrate-resistant prostate cancer (CRPC), we proposed a concept showing that, in order to improve applicability of current knowledge in oncology, the re-clustering of clinical and scientific data is crucial. Such an approach, based on systems oncology, would include bridging of data on biomarkers and pathways between different cancer types. Proposed concept would introduce a new matrix, which enables combining of already approved therapies between cancer types. Paper provides a (a) detailed analysis of similarities in mechanisms of etiology and progression between PaC and CRPC, (b) diabetes as common hallmark of both cancer types and (c) knowledge gaps and directions of future investigations. Proposed horizontal and vertical matrix in cancer profiling has potency to improve current antineoplastic therapy efficacy. Systems biology map using Systems Biology Graphical Notation Language is used for summarizing complex interactions and similarities of mechanisms in biology of PaC and CRPC.

The association between sex hormone-binding globulin gene polymorphism with bone mineral density

To investigate the impact of single nucleotide polymorphisms (SNPs) of SHBG gene the neighboring genes on SHBG levels, bone mineral density (BMD) and osteoporosis in Chinese males. A group of Chinese men, aged ⩾ 45 years were included in the analysis. BMD was measured with dual-energy X-ray absorptiometry (DXA), SHBG and total testosterone (TT) was measured using chemiluminescent immunoassay, and free testosterone (FT) was calculated. SNPs of SHBG gene and the neighboring genes were studied by means of improved multiple ligase detection reaction (iMLDR). A total of 404 men were included in our study. In the single locus analysis, significant associations were found between SHBG levels and four polymorphisms (rs11078701, rs9901675, rs9898876 and rs2541012) in age- and BMI-adjusted models. In addition, statistically significant difference was found between osteoporosis patients and control subjects in genotype distributions of rs9898876, rs2541012, rs6259 and rs3853894. In the models with or without adjustment for confounders (age, BMI, SHBG and free testosterone (FT) levels), carriers of variant genotype of rs9898876, rs2541012 and rs6259 had lower BMD and were more likely to suffer from osteoporosis, as compare to carriers of common genotype. Subjects with variant genotype of rs3853894 had higher BMD and were less likely to suffer from osteoporosis, as compared to subjects with common genotype. In the haplotypes analysis, CCGGT (constituted by rs11078701C, rs1017163C, rs9898876G, rs62059836G and rs2541012T) and haplotype CGGT (constituted by rs858521C, rs858518G, rs6259G and rs727428T) was associated with a significant risk effect for osteoporosis. Polymorphisms of SHBG or the neighboring genes were associated with SHBG levels or BMD and osteoporosis, suggesting the involvement of genetic variation of SHBG in bone health.

The association between estrogen receptor alpha polymorphisms and the risk of prostate cancer in Slovak population

The aim of our study was to evaluate the effect of two polymorphisms in the estrogen receptor alpha, PvuII and XbaI, on the development of prostate cancer within Slovak population, as well as their correlation with selected clinical characteristics. The study was performed using 311 prostate cancer patients and 256 healthy male controls. Both polymorphisms were significantly associated with higher risk of prostate cancer development. At the same time, the CC genotype of PvuII polymorphism (OR = 1.98; 95% CI 0.94-4.21; p = 0.05) and the AG genotype of XbaI polymorphism (OR = 1.74; 95% CI 1.0-3.02; p = 0.04) significantly contributed to the development of low-grade carcinoma, while the AG and GG genotypes of the XbaI polymorphism contributed mainly to the development of high-grade prostate cancer (OR = 1.83; 95% CI 1.12-3.01; p = 0.01 and OR = 2.13; 95% CI 1.06-4.19; p = 0.03, respectively). Similarly, the AG and GG genotypes of XbaI polymorphism showed significant association with prostate cancer in patients with serum PSA level ≥10 ng/ml. Both polymorphisms were found at the same time to be more frequent in patients diagnosed before the age of 60. We conclude on the basis of these results that PvuII and XbaI polymorphisms of estrogen receptor alpha might be associated with prostate cancer risk within Slovak population. Although this is a pilot study and, as such, more detailed investigations are needed to confirm the role of these polymorphisms in prostate cancer development and progression within said Slovak population, our results might still provide a valuable basis for further research with larger patient groups.