Interleukin-13 rs1800925/-1112C/T promoter single nucleotide polymorphism variant linked to anti-schistosomiasis in adult males in Murehwa District, Zimbabwe

Background

Chronic schistosomiasis is predominantly induced through up-regulation of inflammatory cytokines such as interleukin (IL)-13. IL-13 may contribute to the disease outcomes by increasing eosinophil infiltration thereby promoting fibrosis. IL-13 may act as an immunosuppressive inflammatory cytokine that may promote carcinogenesis and also may offer protection against schistosomiasis thereby reducing risk of schistosome infections. Our study evaluated the frequency of the IL-13 rs1800925/-1112 C/ T promoter single nucleotide polymorphisms (SNPs) among schistosomiasis infected individuals and assessed the association of the variants on IL-13 cytokine levels. We also investigated IL-13 rs1800925 polymorphisms on prostate-specific antigen levels as an indicator for risk of prostate cancer development.

Methodology

The study was cross-sectional and included 50 schistosomiasis infected and 316 uninfected male participants residing in Murehwa District, Zimbabwe. IL-13 rs1800925 SNPs were genotyped by allele amplification refractory mutation system-polymerase chain reaction. Concentrations of serum prostate-specific antigens and plasma IL-13 were measured using enzyme-linked immunosorbent assay.

Results

Frequencies of the genotypes CC, CT and TT, were 20%, 58% and 22% in schistosomiasis infected, and 18.3%, 62.1% and 19.6% in uninfected participants with no statistical differences. There were significantly (p<0.05) higher IL-13 cytokine levels among both infected and uninfected participants with the genotypes CC and CT; median 92.25 pg/mL and 106.5 pg/mL, respectively, compared to TT variant individuals; 44.78 pg/mL. Within the schistosomiasis uninfected group, CC and CT variants had significantly (p<0.05) higher IL-13 levels; median 135.0 pg/mL and 113.6 pg/mL, respectively compared to TT variant individuals; 47.15 pg/mL. Within the schistosomiasis infected group, CC, CT and TT variant individuals had insignificant differences of IL-13 level. Using logistic regression, no association was observed between prostate-specific antigen levels, IL-13 cytokine levels and IL-13 rs1800925 variants (p>0.05).

Conclusion

IL-13 rs1800925 C variant individuals had the highest IL-13 cytokine levels among the schistosomiasis uninfected suggesting that they may be protective against Schistosoma infections. There was no association between IL-13 concentrations or IL-13 rs1800925 variants and risk of prostate cancer indicating that IL-13 levels and IL-13 rs10800925 may not be utilised as biomarker for risk of prostate cancer in schistosome infections.

Possible association and co-existence of schistosome infection and prostate cancer: A systematic review

Male genital schistosomiasis (MGS) may result in eggs lodged in the prostate causing persistent inflammation that may play a major role in prostate carcinogenesis. Globally, prostate cancer (PCa) is one of the most common cancers and the global distribution of PCa overlaps with that of schistosomiasis infections, suggesting a probable causal relationship. Objectives of this review were to assess evidence of co-existence of schistosomiasis and PCa and possible causal association between the two diseases. Relevant literature published between 1950 and 2019 yielded 20 publications on schistosomiasis and PCa co-existence. Schistosoma (S.) haematobium and S. mansoni were associated with MGS manifestation and mostly prostate adenocarcinoma diagnosis. Effects of prostatic MGS infection progressed over time with high Schistosoma egg burden thought to contribute to the development of PCa. Causal association and mechanistic pathways of MGS on PCa development and the role of Schistosoma eggs on the development of PCa remains unestablished.

Association of schistosomiasis and risk of prostate cancer development in residents of Murehwa rural community, Zimbabwe

Background

Prostatic male genital schistosomiasis and prostate cancer co-existence cases are uncommon however, some studies have indicated that schistosomiasis may trigger development of prostate cancer regardless of age. Schistosomiasis is a public health problem in sub-Saharan Africa and may account for some undocumented cases of schistosomiasis prostatic cancer in schistosome endemic rural communities. It is against this background that we investigated the association between schistosomiasis and risk of prostate cancer development in residents of Murehwa Community, a schistosomiasis endemic area.

Methodology

We conducted a cross sectional study involving 366 men residing in Murehwa District, Zimbabwe. Schistosoma haematobium and S. mansoni infection was diagnosed using urine filtration and Kato Katz techniques, respectively. Haematuria was detected using urinalysis reagent strip test. A structured questionnaire was used to obtain history of schistosomiasis infection among study participants. Risk of prostate cancer development was assessed by measuring prostate-specific antigen levels in serum using the ELISA.

Results

Prevalence of S. haematobium and S. mansoni infection was 12.3% and 1.4%, respectively. Individuals with schistosomiasis had higher prostate-specific antigen levels (mean 1.208 ± SD 1.557 ng/mL) compared to those without schistosomiasis (mean 0.7721 ± SD 1.173 ng/mL; p < 0.05). Older individuals > 50 years had higher prostate specific antigen levels (mean 0.7212 ± SD 1.313 ng/mL) compared to individuals < 50 years old (mean 0.4159 ± SD 0.8622 ng/mL; p < 0.05). Prostate-specific antigen levels log₁₀ (mean 0.2584 ± SD 0.2128 ng/mL) and were associated to S. haematobium infection intensity log₁₀ (mean 1.121 ± SD 0.5371 eggs/10 mL), r(s) = − 0.3225, p < 0.05. There was a correlation between prostate-specific antigen levels log₁₀ (mean 0.2246 ± SD 0.1858 ng/mL) and S. haematobium infection intensity log₁₀ (mean 1.169 ± SD 0.5568 eggs/10 mL) among participants with a history of schistosomiasis infection (r(s) = − 0.3520; p < 0.05). There was no correlation between prostate-specific antigen levels of > 4 ng/mL (mean 5.324 ± SD1.568 ng/mL) and schistosome eggs log₁₀ (mean 1.057 ± SD 0.6730 eggs/10 mL; p > 0.05).

Conclusion

Urogenital schistosome infections and history of schistosome infections were associated with prostate specific antigen levels, an indicator for risk of prostate cancer. Therefore, S. haematobium schistosome egg burden was associated with the risk of prostate cancer development in adult males residing in Murehwa District, Zimbabwe.