背景:西妥昔单抗广泛用于治疗转移性结直肠癌(mCRC)。然而,耐药性对成功的治疗提出了重大挑战。最近,下垂,非经典的程序性细胞死亡,其在抗肿瘤治疗中的潜在应用价值引起了越来越多的关注。我们旨在鉴定参与凋亡抑制的基本途径和信号分子,并选择它们作为西妥昔单抗耐药的治疗靶点。此外,工程外泌体技术被用作具有靶向和效应特性的药物递送系统。
结果:通过比较耐药结肠癌细胞和敏感细胞之间的凋亡相关基因的差异表达,观察到西妥昔单抗诱导的凋亡水平在耐药细胞中显著下调.京都基因和基因组百科全书(KEGG)分析确定粘着斑激酶(FAK)信号通路是参与抑制凋亡的关键通路。通过细胞形态学观察研究FAK在西妥昔单抗耐药细胞中的生物学功能,CCK-8测定,集落形成试验,RT-qPCR,西方印迹,和功能丧失实验。结果显示FAK信号通路在西妥昔单抗耐药结肠癌细胞中显著上调,靶向FAK的siRNA干扰可以显著抑制细胞增殖,同时上调凋亡水平。基于此,构建靶向工程结肠癌细胞和FAKsiRNA外泌体(CT-Exo-siFAK1)。体外实验,CT-Exo-siFAK1可以有效激活凋亡并抑制耐药结肠癌细胞的增殖。体内实验还证实,CT-Exo-siFAK1可显着抑制肿瘤的生长和转移,同时上调上睑下垂水平。
结论:这项研究表明,FAK信号通路介导的凋亡水平抑制在西妥昔单抗靶向治疗结肠癌的敏感性中至关重要。使用工程化的外泌体递送FAKsiRNA可能是逆转西妥昔单抗耐药性的有效策略。
BACKGROUND: Cetuximab is extensively used in the treatment of metastatic colorectal cancer (mCRC). However, resistance poses a significant challenge to successful therapy. Recently,
paraptosis, a non-classical programmed cell death, has garnered increased attention for its potential application value in antitumor treatments. We aimed to identify the essential pathways and signaling molecules involved in
paraptosis inhibition and select them as therapeutic targets in cetuximab resistance. Additionally, engineered exosome technology is used as a drug delivery system with both targeted and effector properties.
RESULTS: By comparing the differential expression of paraptosis-related genes between drug-resistant colon cancer cells and sensitive cells, it was observed that the
paraptosis level induced by cetuximab was significantly downregulated in drug-resistant cells. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified the focal adhesion kinase (FAK) signaling pathway as a key pathway involved in the suppression of paraptosis. The biological function of FAK in cetuximab-resistant cells was investigated through cell morphology observation, CCK-8 assay, colony formation assay, RT-qPCR, Western Blot, and loss-of-function experiments. The results showed that the FAK signaling pathway was significantly upregulated in cetuximab-resistant colon cancer cells, and siRNA interference targeting FAK could notably inhibit cell proliferation while upregulating the paraptosis level. Based on this, engineered colon cancer cells targeted and FAK siRNA loaded exosomes (CT-Exo-siFAK1) were constructed. In vitro experiments, CT-Exo-siFAK1 could effectively activate
paraptosis and inhibit the proliferation of drug-resistant colon cancer cells. In vivo experiments also confirmed that CT-Exo-siFAK1 significantly suppressed tumor growth and metastasis while upregulating the paraptosis level.
CONCLUSIONS: This study suggests that FAK signaling pathway-mediated inhibition of
paraptosis levels is crucial in the sensitivity of cetuximab targeted therapy in colon cancer, and the use of engineered exosomes to deliver FAK siRNA may be an effective strategy to reverse cetuximab resistance.