Alternative activation of hedgehog pathway induced by ultraviolet B radiation: preliminary study

PTCH1 gene variants rs357564, rs2236405, rs2297086 and rs41313327, mRNA and tissue expression in basal cell carcinoma patients from Western Mexico

BACKGROUND

Basal cell carcinoma (BCC) represents about 80% of all cases of skin cancer. The PTCH1 is a transmembrane protein of the Sonic Hedgehog signaling pathway that regulates cell proliferation. Genetic variants in PTCH1 gene have been previously described in association with BCC development. In addition, PTCH1 mRNA and protein expression analysis are also significant to understand its role in skin cancer physiopathology.

METHODS

An analytical cross-sectional study was performed, and a total of 250 BCC patients and 290 subjects from the control group (CG) were included, all born in western Mexico. The genotypes and relative expression of the mRNA were determined by TaqMan® assay. The protein expression was investigated in 70 BCC paraffin-embedded samples with PTCH1 antibodies. Semi-quantitative analysis was performed to determine the expression level in the immunostained cells.

RESULTS

We did not find evidence of an association between PTCH1 rs357564, rs2297086, rs2236405, and rs41313327 genetic variants and susceptibility to BCC. Likewise, no statistically significant differences were found in the comparison of the mRNA level expression between BCC and CG (p > 0.05). The PTCH1 protein showed a low expression in 6 of the analyzed samples and moderate expression in 1 sample. No association was found between genetic variants, protein expression, and demographic-clinical characteristics (p > 0.05).

CONCLUSION

The studied PTCH1 variants may not be associated with BCC development in the Western Mexico population. The PTCH1 mRNA levels were lower in patients with BCC compared to the control group, but its protein was underexpressed in the tissue samples.

Daily Lifestyle and Cutaneous Malignancies

Daily lifestyle is a fundamental part of human life and its influence accumulates daily in the human body. We observe that a good daily lifestyle has a beneficial impact on our health; however, the actual effects of individual daily lifestyle factors on human skin diseases, especially skin cancers, have not been summarized. In this review, we focused on the influence of daily lifestyle on the development of skin cancer and described the detailed molecular mechanisms of the development or regulation of cutaneous malignancies. Several daily lifestyle factors, such as circadian rhythm disruption, smoking, alcohol, fatty acids, dietary fiber, obesity, and ultraviolet light, are known to be associated with the risk of cutaneous malignancies, malignant melanoma, squamous cell carcinoma, basal cell carcinoma, and Merkel cell carcinoma. Although the influence of some daily lifestyles on the risk of skin cancers is controversial, this review provides us a better understanding of the relationship between daily lifestyle factors and skin cancers.

STAT3 polymorphisms and IL-6 polymorphism are associated with the risk of basal cell carcinoma in patients from northern Poland

Basal cell carcinoma (BCC) environment consists of stromal and inflammatory cells which produce variety of cytokines, chemokines and growth factors that may affect tumor behavior. One of the cytokines suggested to be involved in the pathogenesis of BCC is IL-6, which is the upstream element of IL-6/JAK/STAT3 pathway. The correlation between polymorphisms of the genes related to this pathway and cancer risk/prognosis have been previously investigated in several neoplasia, but available data concerning BCC are scarce. In the present study, rs1800795 (-174 G/C) IL-6 gene polymorphism and two polymorphisms in the STAT3 gene, namely rs2293152 (intron 11, C/G) and rs4796793 (-1697, C/G) were assessed in relation to the BCC risk and clinical course. Additionally, IL-6 serum level was assessed in relation to IL-6 genotype and clinical variables. The study included 254 unrelated patients with BCC and of mean age 70.39 ± 11.43 (69.83 ± 12.32 women, 71.03 ± 10.31 men) and 198 healthy, unrelated age- and sex-matched volunteers. IL-6 and STAT3 polymorphisms were analyzed using polymerase chain reaction with sequence-specific primers (SSP-PCR). Serum concentration of IL-6 was measured using the ELISA test. We have found that the presence of C allele in rs1800795 IL-6 gene polymorphism was associated with increased risk of BCC (aOR 1.86; 95% CI 1.22–2.84; p = 0.004). The presence of CC genotype in STAT3 rs2293152 polymorphism was associated with increased BCC risk in recessive model analysis (aOR 3.94; 95% CI 1.59–9.77; p = 0.003). In contrast, the presence of GC genotype in overdominant model was associated with decreased risk of BCC (aOR = 0.24; 95% CI 0.12–0.49; p < 0.0001). The presence of C allele in STAT3 rs2293152 polymorphism was associated with increased risk of BCC (aOR 1.31; 95% CI 1.01–1.69; p = 0.04). The presence of GG genotype in STAT3 rs4796793 polymorphism was associated with increased BCC risk in recessive model analysis (aOR 3.66; 95% CI 1.33–10.10; p = 0.012). The presence of G allele in STAT3 rs4796793 polymorphism was associated with increased risk of BCC (aOR 1.59; 95% CI 1.01–2.49; p = 0.04). IL-6 serum level positively correlated with the tumor size.