Sirtuin 1 (SIRT1) regulates DNA repair and metabolism by deacetylating target proteins. SIRT1 may be oncogenic because its overexpression has been detected in many cancers. The aim of the present study was to clarify the prognostic role of SIRT1 in patients with esophageal squamous cell carcinoma (ESCC) and evaluate the effect of SIRT1 inhibitor in vitro. The expression of SIRT1 was evaluated immunohistochemically in 155 surgically resected ESCC and the staining results were evaluated semiquantitatively by the Immunoreactive Scoring System. The clinical features and treatment outcome were analyzed. The effect of SIRT1 inhibitor, SIRT 1 inhibitor IV, (S)-35, was investigated in vitro on ESCC cell lines. The expression of SIRT1 on ESCC did not correlate with age, gender, tumor location, stage, T classification, N classification, surgical margin or histology. Univariate analysis showed that SIRT1 overexpression was associated with inferior overall survival (P = 0.004) and disease-free survival (P = 0.004). In multivariate comparison, SIRT1 overexpression remained independently associated with worse overall survival (P = 0.009, hazard ratio = 1.776) and disease-free survival (P = 0.017, hazard ratio = 1.642). In cell lines, SIRT1 inhibitor inhibited ESCC growth. Our study suggests that SIRT1 overexpression is an independent prognosticator for patients with ESCC and the SIRT1 inhibitor suppressed cell proliferation of ESCC cell lines. Our findings suggest that inhibition of SIRT1 signaling may be a promising novel target for ESCC.

Low-level cadmium exposure has adverse effects on chronic kidney disease (CKD); however, the risk factors for elevated blood cadmium levels (BCLs) have not been studied in CKD. We conducted a cross-sectional investigation in 200 CKD patients and stratified them by the tertiles of BCL to compare their demographic, environmental, and biochemical data. The factors associated with BCL were identified, and their effects were examined in subgroups. In the analyses, female sex, smoking, and CKD stage 5D were associated with high BCL, and statin was inversely correlated with BCL (odds ratio [95% confidence interval, CI], 6.858 [2.381–19.746], p < 0.001, 11.719 [2.843–48.296], p = 0.001, 30.333 [2.252–408.520], p = 0.010, and 0.326 [0.122–0.873], p = 0.026; deviations of BCL [nmol/L, 95% CI], 2.66 [1.33–4.00], p < 0.001, 3.68 [1.81–5.56], p < 0.001, 3.38 [0.95–5.82], p = 0.007, and −2.07 [−3.35–−0.78], p = 0.002). These factors were also independently correlated with BCL in subgroups, including non-dialysis CKD, hypertensive patients, non-smokers, and male patients. In conclusion, female sex, smoking, and CKD stage 5D were the major risk factors for elevated BCL; additionally, statins were negatively associated with BCL in CKD.