Can lower aldehyde dehydrogenase activity in saliva be a risk factor for oral cavity cancer?

Abstract

Objectives: Salivary ALDH3A1 protects the oral cavity from aromatic and medium-chain aliphatic aldehydes originating from food and air pollution and generated during oxidative stress. Due to their reactivity, aldehydes may exhibit an irritating effect as well as cytotoxic, genotoxic, mutagenic and even carcinogenic effects. The aim of this study was to verify whether lower ALDH3A1 activity is a risk factor for oral cavity cancer.

Subjects and methods: Fasting saliva samples were collected one day before and about one week after surgery from patients with oral cancer (OCC) (n = 59), other tumours (cysts, neoplasms) (n = 108), gnathic defects and fractures (controls after the surgery) (n = 63), and from healthy volunteers (n = 116). Enzyme activity was measured using a fluorometric method.

Results: Total ALDH3A1 activity [U g(-1) ] in patients with OCC was statistically lower than in patients with keratocystic odontogenic tumour (KCOT) (P = 0.00697), odontogenic cysts (OC) (P < 0.00001), neoplasms (P = 0.03343) and the healthy volunteers up to and over 40 years old (P < 0.00001; P = 0.00019). The activity in the saliva of OCC after surgery was lower than in the healthy volunteers (P < 0.00001) and in the groups with fractures (P = 0.00303) and gnathic defects (P = 0.00538).

Conclusion: Low salivary ALDH activity may be a risk factor for oral cancer development.

Keywords: ALDH3A1; cyst; oral cancer; saliva.