Characterization of Wnt signaling pathway under treatment of Lactobacillus acidophilus postbiotic in colorectal cancer using an integrated in silico and in vitro analysis

Abstract

Colorectal cancer (CRC) is a prevalent and life-threatening cancer closely associated with the gut microbiota. Probiotics, as a vital microbiota group, interact with the host’s colonic epithelia and immune cells by releasing a diverse range of metabolites named postbiotics. The present study examined the effects of postbiotics on CRC’s prominent differentially expressed genes (DEGs) using in silico and in vitro analysis. Through single-cell RNA sequencing (scRNA-seq), we identified four DEGs in CRC, including secreted frizzled-related protein 1 (SFRP1), secreted frizzled-related protein 2 (SFRP2), secreted frizzled-related protein 4 (SFRP4), and matrix metallopeptidase 7 (MMP7). Enrichment analysis and ExpiMap, a novel deep learning-based method, determined that these DEGs are involved in the Wnt signaling pathway as a primary cascade in CRC. Also, spatial transcriptome analysis showed specific expression patterns of the SFRP2 gene in fibroblast cell type. The expression of selected DEGs was confirmed on CRC and normal adjacent tissues using Real-Time quantitative PCR (RT-qPCR). Moreover, we examined the effects of postbiotics extracted from Lactobacillus acidophilus (L. acidophilus) on the proliferation, migration, and cell cycle distribution of HT-29 cells using MTT, scratch, and flow cytometry assays. Our results showed that L. acidophilus postbiotics induce cell cycle arrest at G1 phase and also had anti-proliferative and anti-migration effects on HT-29 cells, while it did not exert anti-proliferative activity on control fibroblasts. Finally, we revealed that treating HT-29 cells with postbiotics can affect the expression of selected DEGs. We suggested that L. acidophilus postbiotics have therapeutic potential in CRC by modulating key genes in the Wnt pathway.