Antiproliferative Properties of Lichens Parmelia vagans and Parmelia sulcata

Abstract

The purpose of this project was to analyze antiproliferative properties of the secondary metabolites extracted from lichens Parmelia vagans and Parmelia sulcata collected from the semi‐deserts of Russia. An isolation and characterization of novel natural compounds that can selectively slow down or stop proliferation of cancer cells can enhance development of anticancer therapeutics.Various lichen extracts were prepared using either water or organic solvents. We assessed the antiproliferative activity against several human cancer cell lines; human hepatocellular carcinoma (Hep G2), human non‐small cell lung cancer (NCI‐H1299), and human mammary gland ductal carcinoma (T‐47D). The same number of cells of different cell lines were plated into a 96‐well plate and allowed to adhere overnight. Next day, different dilutions of the lichen extracts were added to the adhered cells and the plate was placed in CO2 incubator for 6–72 hours. By the end of the incubation time a picture of each well was taken to assess cell confluency and the cells were subjected to Resazurin assay to analyze the effect of the lichen extracts on cell growth and proliferation. After Resazurin assay, the cells in each well were treated with trypsin, suspended in growth medium and counted using Bio‐Rad cell counter to evaluate a percent of live cells.Our experimental data from cell viability assay and live cells count indicate that bottled water and ethyl acetate extracts of P. vagans and P. sulcata significantly suppress (30%–60%) the growth of human hepatocellular carcinoma and human non‐small cell lung carcinoma. We also found that cancer cells treated by the lichen extracts results in their morphological changes that resemble an activation of apoptosis.Our findings indicate that these lichen species produce secondary metabolites that slow cancer cells growth and proliferation. Future experiments will be focused on isolation and characterization of the compounds from P. vagans and P. sulcata crude extracts that are responsible for the inhibition of cancer cells growth. Another important direction of the future research is to identify the cellular target(s) of the antiproliferative compound(s) and its molecular mechanism of action. I summary, the lichen's secondary metabolites may hold a vast medicinal potential and could be a viable source of a novel of anticancer drugs.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.