Expression of Circulating Mir-206 in Patients with Lung and Head and Neck Cancers and its Association with Cancer Cachexia

Background: cancer cachexia is a common problem found in advanced stage cases. Pathophysiology of cachexia is complicated, involving cytokines and regulator molecules such as microRNA (miRNA). MiR-206, a specific miRNA in skeletal muscle cells was thought to play important role in regulating skeletal muscle loss but have not been studied well in cachectic patients. Objective: to evaluate the clinical significance of circulating miR-206 in cancer patients presenting with cancer cachexia. Method: A cross-sectional study was performed in Dharmais Cancer Hospital, Jakarta between September and December 2015. Patients enrolled were lung and head and neck cancers. Cachexia was defined as body mass index less than 20 kg/m2. MiR-206 expression was assayed using quantitative real-time polymerase chain reaction (RT-PCR), whereas miR-16 served as internal control. The results were expressed as cycle threshold (CT) and fold change (FC) which was calculated using the 2-ΔΔCT method. Results: Seventy patients were enrolled during the study period; consisting 37 (52.9%) lung 33 (47.1%) head and neck cancers. There were 31 (41.3%) patients presenting with cachexia. Serum miR-206 was overexpressed in cancer patients compare to normal healthy subjects. MicroRNA-206 expression was slightly up-regulated in cachectic patients than non-cachectic patients, i.e. FC=1.355 in lung cancers and FC=1.438 in head and neck cancers. Conclusion: Circulating miR-206 is overexpressed advanced stage lung cancer as well as head and neck cancer patients. Increased circulating miR-206 in cachectic patients may reflect extensive skeletal muscle loss associated with cancer cachexia.