J Cancer 2021; 12(12):3468-3485. doi:10.7150/jca.50793
The Effects of Lentivirus-Mediated Gene Silencing of RARβ on the Stemness Capability of Non-Small Cell Lung Cancer
1. Lung Stem Cell and Gene Therapy Group, Regenerative Medicine Cluster, Advanced Medical and Dental Institute (IPPT), Sains@Bertam, Universiti Sains Malaysia, Kepala Batas Penang, 13200, Malaysia.
2. Infectomics Cluster, Advanced Medical and Dental Institute (IPPT), Sains@Bertam, Universiti Sains Malaysia, Kepala Batas Penang, 13200, Malaysia.
3. Henan Joint International Research Laboratory of Stem Cell Medicine, Xinxiang Medical University (XXMU), Henan Province 453000, China.
4. Stem Cell and Biotherapy Technology Research Centre of Henan Province, Xinxiang Medical University (XXMU), Henan Province 453000, China.
5. Stem Cell Laboratory, Haematology Unit, Cancer Research Centre (CaRC), Institute for Medical Research (IMR), National Institute of Health, Setia Alam, 40170 Shah Alam, Selangor.
Abu Halim NH, Zakaria N, Theva Das K, Lin J, Lim MN, Fakiruddin KS, Yahaya BH. The Effects of Lentivirus-Mediated Gene Silencing of RARβ on the Stemness Capability of Non-Small Cell Lung Cancer. J Cancer 2021; 12(12):3468-3485. doi:10.7150/jca.50793. Available from https://www.jcancer.org/v12p3468.htm
Retinoic acid receptor beta is a nuclear receptor protein that binds to retinoic acid (RA) to mediate cellular signalling in embryogenic morphogenesis, cell growth, and differentiation. However, the function of RARβ in cancer stem cells (CSCs) has yet to be determined. This study aimed to understand the role of RARβ in regulating cell growth and differentiation of lung cancer stem cells. Based on the clonogenic assay, spheroid assay, mRNA levels of stem cell transcription factors, and cell cycle being arrested at the G0/G1 phase, the suppression of RARβ resulted in significant inhibition of A549 parental cell growth. This finding was contradictory to the results seen in CSCs, where RARβ inhibition enhanced the cell growth of putative and non-putative CSCs. These results suggest that RARβ suppression may act as an essential regulator in A549 parental cells, but not in the CSCs population. The findings in this study demonstrated that the loss of RARβ promotes tumorigenicity in CSCs. Microarray analysis revealed that various cancer pathways were significantly activated following the suppression of RARβ. The changes seen might compensate for the loss of RARβ function, CSCs population's aggressiveness, which led to the CSCs population's aggressiveness. Thus, understanding the role of RARβ in regulating the stemness of CSCs may lead to targeted therapy for lung CSCs.
Keywords: non-small cell lung cancer, gene silencing, RAR1-beta, cancer stem cells