Impact of Nordihydroguaiaretic Acid on Proliferation, Energy Metabolism, and Chemosensitization in Non-Small-Cell Lung Cancer (NSCLC) Cell Lines

Lung cancer (LC) is the leading cause of cancer death worldwide. LC can be classified into small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC), with the last subtype accounting for approximately 85% of all diagnosed lung cancer cases. Despite the existence of different types of treatment for this disease, the development of resistance to therapies and tumor recurrence in patients have maintained the need to find new therapeutic options to combat this pathology, where natural products stand out as an attractive source for this search. Nordihydroguaiaretic acid (NDGA) is the main metabolite extracted from the Larrea tridentata plant and has been shown to have different biological activities, including anticancer activity. In this study, H1975, H1299, and A549 cell lines were treated with NDGA, and its effect on cell viability, proliferation, and metabolism was evaluated using a resazurin reduction assay, incorporation of BrdU, and ki-67 gene expression and glucose uptake measurement, respectively. In addition, the combination of NDGA with clinical chemotherapeutics was investigated using an MTT assay and Combenefit software (version 2.02). The results showed that NDGA decreases the viability and proliferation of NSCLC cells and differentially modulates the expression of genes associated with different metabolic pathways. For example, the LDH gene expression decreased in all cell lines analyzed. However, GLUT3 gene expression increased after 24 h of treatment. The expression of the HIF-1 gene decreased early in the H1299 and A549 cell lines. In addition, the combination of NDGA with three chemotherapeutics (carboplatin, gemcitabine, and taxol) shows a synergic pattern in the decrease of cell viability on the H1299 cell line. In summary, this research provides new evidence about the role of NDGA in lung cancer. Interestingly, using NDGA to enhance the anticancer activity of antitumoral drugs could be an improved therapeutic resource against lung cancer.