Identification of Differential Genes by Microarray and COL6A1 Induced the Bone Metastasis of Non-Small Cell Lung Cancer

Abstract Background: Non-small cell lung cancer (NSCLC) is a major cause of cancer-related death worldwide with bone metastasis as the most prevalent events in advanced cancer patients. However, its pathogenesis has not been clearly described. Methods: In the present study, differentially expressed genes (DEGs) were filtered through gene expression microarray between NSCLC tissue samples with or without bone metastasis. Subsequently, collagen family collagen 6A1 (COL6A1) was chosen as the target gene through Ingenuity Pathway Analysis and qRT-PCR validation of the 8 Top genes. And we evaluated the osteogenic capacity of HOB and hES-MP 002.5 cells through RT-qPCR, Western blot, Alizarin Red Staining and ALP staining.Results: A total of 364 DEGs including 140 up-regulated genes and 224 down-regulated genes were identified in NSCLC tissues with bone metastasis. GO analysis indicated that the upregulated and downregulated genes were mainly enriched in cellular process, metabolic process and biological regulation. KEGG pathway analysis revealed that the upregulated genes were mainly concentrated in cysteine and methionine metabolism, oxidative phosphorylation, and ribosome; the downregulated genes were mainly concentrated in the transcriptional misregulation in cancer, ribosome, and mitophagy-animal. Besides, the results of RT-qPCR, western blot and immunohistochemistry proved that COL6A1 was highly expressed in NSCLC tissue samples with bone metastasis. And we revealed that HOB and hES-MP 002.5 cells have osteogenic capacity through RT-qPCR, Western blot, Alizarin Red Staining and ALP staining . Moreover, the results of cell adhesion assay also proved that high expression of COL6A1 in HARA-B cells can induce its adhesion ability on osteoblasts, and low expression of COL6A1 in HARA-B cells can reduce its adhesion ability on osteoblasts. Conclusions: Therefore, our data revealed that the COL6A1 might represent a diagnostic marker or therapeutic target for bone metastasis in NSCLC.