Lung cancer, predominantly non-small-cell lung cancer (NSCLC), is the leading cause of cancer-related death worldwide. In spite of the tremendous improvements made in the treatment of NSCLC over the past several decades, the prognosis for lung cancer patients has not substantially improved and the overall five-year survival rate of NSCLC patients has remained unfavourable. This is primarily due to the initial diagnosis at advanced stages of disease often accompanied by invasion or lymphatic metastasis.
Early diagnosis is essential for improving lung cancer patients’ survival and there is an urgent need for novel diagnostic biomarkers screening. Accumulating evidence suggests that microRNAs (miRNAs) are key players in the regulation of tumour development and metastasis.
Expression of six miRNAs previously shown to play roles in tumour development (miR-146b-5p, miR-128b, miR-21, miR-221, miR-34a, and Let-7a) in other carcinomas was examined using real-time Real Time-PCR in 78 specimens of NSCLC by Jun Chen and colleagues at the Tianjin Medical University General Hospital in China. Investigators found that patients with low expression of miR-146b-5p had significant shorter median and mean survival time than those with high miR-146b-5p expression. Univariate Cox hazard regression analysis demonstrated that miR-146b-5p expression levels tended to be a significant prognostic indicator of NSCLC. Similarly, multivariate Cox proportional hazard regression analysis showed that miR-146b-5p expression levels were an independent prognostic factor for NSCLC patients.
The findings from this study indicate that the expression levels of miR-146b may have potential applications for more useful clinical stratification of NSCLC patients and enable selection of candidates for additional or alternative treatments.