Oncogenic transformation of human benign prostate hyperplasia with chronic cadmium exposure

Metalloproteinase 9 immunostaining profile is positively correlated with tumor grade, extraprostatic extension and biochemical recurrence in prostate cancer

Metastasis is the main problem in the treatment of prostate cancer (PCa), and for it to occur, proteolytic enzymes must remodel the extracellular matrix (ECM) surrounding the tumor. The most important group of enzymes with this action include the matrix metalloproteinases (MMPs), which act on various substrates cleaving ECM components. The present study aimed to evaluate the protein immunostaining profiles of matrix metalloproteinase 2 (MMP-2) and 9 (MMP-9) in PCa Brazilian patients using the indirect immunohistochemical methodology. The tissue samples (n = 178), 60 from malignant tumor, 58 from adjacent non-tumor, and 60 from ECM, were evaluated according to the immunostaining intensity. The malignant tumor cytoplasmic MMP-2 immunostaining was more intense than in ECM (p = 0.001), but it did not correlate with any clinical-pathological parameter. The MMP-9 staining was similar in tumor cytoplasm, adjacent non-tumor cytoplasm and ECM, but showed significant positive correlations with ISUP grade (p = 0.044; Tau=0.249), extraprostatic extension (p = 0.025; Tau=0.309), and biochemical recurrence (p = 0.048; Tau=0.306). A significant positive correlation was also observed between MMP-2 and MMP-9 in all cell compartments analyzed. Although further research is warranted to elucidate the precise mechanisms underlying these observations, our findings suggest MMP-9 as a promising candidate marker for tissue invasion that could be used in predicting the progression and prognosis of PCa.

Cadmium exposure and the risk of prostate cancer among Nigerian men: effect modification by zinc status

BACKGROUND

Prostate cancer (PCa) may result from an interplay between many factors including exposure to trace elements. This study examined the association between cadmium exposure and PCa among Nigerian men and evaluated possible modification of this effect by zinc status.

METHODS

This case-control study involved men with histologically confirmed PCa (n = 82), benign prostatic hyperplasia (BPH; n = 93) and controls (n = 98), aged between 40 and 80 years. Study participants were recruited from the main teaching hospital that draws clients from the entire Anambra State in South-Eastern Nigeria. Blood and urine samples were collected from these participants and were analyzed for trace elements using ICP-MS. Statistical models were used to assess the exposure risk for cadmium exposure as well as the mediating effect of zinc status.

RESULTS

Among men with prostatic disorders (case-case analysis), every 10-fold increase in urinary cadmium was associated with increased risk of PCa (adjusted odds ratios: 2.526; 95% CI: 1.096-5.821). Men in the highest blood zinc quartile had lower odds of PCa compared to the lowest quartile (AOR: 0.19; 95% CI, 0.06-0.54; p-for trend = 0.001). Zinc-specific effect was observed in this group: every 10-fold increase in urinary cadmium was associated with increased risk of PCa among men with creatinine-adjusted urinary zinc levels below the median value (AOR: 8.46; 95% CI: 1.97 -36.39) but not in those above the median value (AOR: 1.55; 95% CI: 0.45 - 5.39).

CONCLUSION

Higher exposure to cadmium may be associated with increased risk of PCa in Nigeria and probably other countries with high prevalence of Zn deficiency. These results point to the need to consider co-occurring trace metals in any effort to mitigate the toxicity of Cd in the environment.

Circ_0027470 promotes cadmium exposure-induced prostatic fibrosis via sponging miRNA-1236-3p and stimulating SHH signaling pathway

Cadmium (Cd) is a toxic heavy metal pollutant and serves as an important environmental endocrine-disrupting chemical. Cd exposure is believed to can enhance the risks of age-related disorders including benign prostatic hyperplasia (BPH). This study was to investigate the harms of Cd exposure on mice prostate and human nonmalignant prostate epithelial RWPE-1 cells. Mice prostate fibrosis was evaluated by visualizing the prostatic collagen deposition via Masson and Sirius red staining, and detecting the content of hydroxyproline. Additionally, the epithelial-mesenchymal transition (EMT), primary ciliogenesis and SHH signaling pathways in both mice prostate and RWPE-1 cells were evaluated. It was found that Cd exposure stimulated prostatic collagen deposition, EMT and primary ciliogenesis, as well as enhanced the circ_0027470 level and reduced the miRNA-1236-3p level. Circ_0027470 functioned as a sponge of miRNA-1236-3p, which had the inhibiting target of SHH. The whole results showed that circ_0027470 promoted Cd exposure-induced prostatic fibrosis via sponging miRNA-1236-3p and subsequently stimulating SHH signaling pathway. This study shed a light on a novel molecular mechanism involved in circRNA for Cd exposure-induced prostate deficits.

Chronic Cadmium Exposure and Genetic Polymorphisms of MMP-2 and MMP-9 in a Population Exposed to Steel Slag in the State of Rio de Janeiro, Brazil: A Cross-Sectional Study

Genetic polymorphisms in the matrix metalloproteinases (MMPs) family genes may be associated with cadmium (Cd) levels and its adverse effects. This study investigated the impact of MMP-2 and MMP-9 polymorphisms on Cd levels in 238 residents of a condominium in Rio de Janeiro, Brazil, built over an industrial steel slag waste. Polymorphisms were genotyped using TaqMan validated assays, and the Cd levels were measured in blood (BCd) and urine (UCd) samples by atomic absorption spectrometry. Associations were evaluated by linear correlation coefficients and multiple logistic regression, using odds ratios (OR) and 95% confidence intervals (CI). Mean age was 50 ± 15 years; 58% were female, 69% non-smokers. Mean concentrations for BCd and UCd were 0.70 ± 0.2 μg L^-1 and 0.56 ± 0.55 μg L^-1, respectively. Smoking status was associated with BCd ≥ 0.70 μg L^-1 (OR = 2.9; 95% CI = 1.6-5.9). MMP-9 rs17576 A > G was associated with BCd ≥ 0.70 μg L^-1 (OR = 2.11; 95% CI = 1.10-4.05) and UCd ≥ 0.56 μg L^-1 (OR = 3.38; 95% CI = 1.82-7.65). Knowing possible individual predisposing factors is essential to understand Cd toxicity, and to improve the monitoring of high-risk populations.