Abstract: Objective  To elucidated the specific functional roles of the a disintegrin and metalloproteinase 15 (ADAM15) gene single nucleotide variant (SNV) in the cellular processes associated with the development of colon cancer through combination of high throughput sequencing and suitable cellular models.Methods  We initially performed whole exome sequencing on cancerous tissues and adjacent tissues from colon cancer patients exhibiting invasive phenotypes. Subsequently, functional experiments were conducted using wild-type/mutant ADAM15 colon cancer HCT-8 cell lines. This was followed by transcriptome sequencing analysis of the wild-type/mutant ADAM15 cell lines.Results  The whole exome sequencing study identified a highly recurrent SNV, rs6427128, located at the ADAM15 gene, which demonstrated a significant association with adverse prognosis in patients, suggesting its potential influence on the progression of colon cancer. The functional assays utilizing cells overexpressing the variant gene, indicated that the expression product of this variant gene lost the effect of upregulating cell invasion capabilities while increased cell adhesion by approximately 26% compared to wild-type ADAM15 cells. To comprehensively investigate the mechanisms underlying the impact of rs6427128 variation on colon cancer cell phenotypes, we performed transcriptome sequencing analysis on HCT-8 cells transfected with the overexpressed variant protein. The results revealed differential expression genes were enriched in various cellular biological processes, including cell adhesion junction pathways, DNA replication and transcription, as well as inflammatory responses, in comparison to wild-type samples. Conclusion  This study indicated that the rs6427128 variant may alter the tumor microenvironment by affecting tumor cell adhesion and contributed to extensive transcriptional changes in tumor cells, ultimately promoted the malignant phenotype of colon cancer. Although individual gene mutations in malignant tumors often do not act as primary causative factors, high-frequency recurrent variants detected in clinical samples can provide valuable molecular candidates for unraveling the structural-functional relationships of tumor-related genes. Using rs6427128 as an example, in combination with appropriate cell models and refined analytical methods, some potential functional variants can yield informative laboratory data regarding their specific roles in cellular processes related to the development of colon cancer, such as proliferation, adhesion, invasion, and metastasis.

Key words: colon cancer, a disintegrin and metalloproteinase 15 (ADAM15) gene, cell adhesion, single nucleotide variation (SNV), tumor microenvironment