Can acetylcysteine ameliorate cisplatin-induced toxicities and oxidative stress without decreasing antitumor efficacy? A randomized, double-blind, placebo-controlled trial involving patients with head and neck cancer.

The protective antioxidant activity of acetylcysteine (NAC) against toxicity due to cisplatin has been reported in experimental models; however, its efficacy in patients has not been elucidated. The aim of this study was to investigate the possible protective effect of NAC on cisplatin-induced toxicity and the effect of NAC on clinical response and oxidative stress in patients treated for head and neck cancer. This was a randomized, double-blind, placebo-controlled trial conducted in patients receiving high-dose cisplatin chemotherapy concomitant to radiotherapy. Patients were randomly assigned to groups and received: (a) 600 mg NAC syrup, orally once daily at night for 7 consecutive days or (b) placebo, administered similarly to NAC. Nephro-, oto-, hepato-, myelo-, and gastrointestinal toxicities, clinical responses, and plasma and cellular markers of oxidative stress were evaluated. Fifty-seven patients were included (n = 28, NAC arm; and n = 29, placebo arm). A high prevalence of most types of toxicities was observed after cisplatin chemotherapy; however, the parameters were similar between the two groups. There was a predominance of partial response to treatment. In the cellular and plasmatic oxidative stress analyses, minor differences were observed. Overall, there was no statistically significant difference between the groups for all outcomes. These findings show that low-dose oral NAC does not protect patients with head and neck cancer from cisplatin-induced toxicities and oxidative stress. The antitumor efficacy of cisplatin was apparently not impaired by NAC.

Cisplatin-induced human peripheral blood mononuclear cells' oxidative stress and nephrotoxicity in head and neck cancer patients: the influence of hydrogen peroxide.

Cisplatin is a widely used antineoplastic agent in the treatment of head and neck cancer. However, it is highly nephrotoxic. Oxidative stress is the main mechanism responsible for cisplatin-induced nephrotoxicity. The aim of this study was to characterize cisplatin-induced nephrotoxicity, oxidative stress in peripheral blood mononuclear cells, and the relationship between them. Twenty-four patients were included in the study. Patients had their blood collected prior to cisplatin administration, and 5 and 20 days after initiating therapy, to assess renal function and to determine oxidative stress with MitoSOX™Red, H2DCF-DA, and Amplex® Red tests. Renal function was assessed by measuring serum creatinine, creatinine clearance, and blood urea nitrogen (BUN). Serum creatinine and creatinine clearance were used to grade nephrotoxicity using Common Terminology Criteria for Adverse Events (CTCAE) v4.0. Compared to baseline values, the mean BUN and serum creatinine increased 135 and 100%, respectively, 5 days after cisplatin infusion. Mean creatinine clearance showed a 43% decrease compared to baseline value. Non-statistically significant changes in superoxide anion (O 2•- ), hydrogen peroxide (H2O2), and general reactive oxygen species production occurred. A higher production of H2O2 was correlated with variation in serum creatinine, and was associated with higher grades for serum creatinine increases and creatinine clearance reductions. Linear regression analyses showed an association between H2O2 production and serum creatinine, creatinine clearance, and BUN levels. These results were observed for 5 days following cisplatin administration. In conclusion, H2O2 production was significantly related to changes in all renal parameters that were evaluated, following the cisplatin infusion.