自地下微生物——细菌属杆状多糖多孢菌（Saccharopolyspora spinosa）中提取的自旋菌素A（Spinosyn A，SPA）及其衍生物LM2I，具有抑制多种癌细胞的潜力。然而，SPA和LM2I在抑制人结直肠癌（colorectal cancer，CRC）细胞的生长以及相关作用机制尚不完全明确。通过使用3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四唑溴化物（MTT）法和克隆形成试验，我们对细胞存活率进行了测定。以SPA和LM2I对七种CRC细胞株的半数抑制浓度（IC50）为基础，筛选出敏感株（HT29和SW480）和不敏感株（SW620和RKO）。利用GSE2509和GSE10843数据集，鉴定出敏感株和不敏感株之间的69个差异表达基因（DEGs）。我们使用基因本体（Gene Ontology，GO）分析，基因组百科全书（Kyoto Encyclopedia of Genes and Genomes，KEGG）富集分析和蛋白质-蛋白质相互作用（protein-protein interactions，PPI）研究了这些DEGs的分子机制。通过Western blot分析和CRISPR/Cas9系统验证，我们发现其中一个DEGs基因是枢纽基因(hub gene)。实验结果表明，SPA和其衍生物LM2I在七种CRC细胞株和结肠癌异种移植瘤中具有显著的抗增殖活性。基于生物信息学分析结果表明，上皮生长因子受体（epidermal growth factor receptor，EGFR）是这些差异表达基因（DEGs）中的枢纽基因，同时也与SPA和LM2I在CRC细胞中的抑制效果相关。研究还发现，SPA和LM2I在体外及体内均抑制EGFR通路的活性。

Spinosyn A (SPA), derived from a soil microorganism, Saccharopolyspora spinosa, and its derivative, LM2I, has potential inhibitory effects on a variety of cancer cells. However, the effects of SPA and LM2I in inhibiting the growth of human colorectal cancer cells and the molecular mechanisms underlying these effects are not fully understood. Cell viability was tested by using a 3-(4,5-dimethylthiazol-2-yl-)-2,5-diphenyltetrazolium bromide (MTT) assay and a colony formation assay. On the basis of the IC50 values of SPA and LM2I in seven colorectal cancer (CRC) cell lines, sensitive (HT29 and SW480) and insensitive (SW620 and RKO) cell lines were screened. The GSE2509 and GSE10843 data sets were used to identify 69 differentially expressed genes (DEGs) between sensitive and insensitive cell lines. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and protein-protein interactions (PPI) were performed to elucidate the molecular mechanisms of the DEGs. The hub gene of the DEGs was detected by Western blot analysis and verified using the CRISPR/Cas9 system. Our data indicate that SPA and its derivative LM2I have significant antiproliferative activity in seven colorectal cancer cell lines and colorectal xenograft tumors. On the basis of bioinformatics analysis, it was demonstrated that epidermal growth factor receptor (EGFR) was the hub gene of the DEGs and was associated with the inhibitory effects of SPA and LM2I in CRC cell lines. The study also revealed that SPA and LM2I inhibited the EGFR pathway in vitro and in vivo.