2025 · Wang et al. Journal of Nanobiotechnology · BioMed Central · added 2026-04-20
Background
Patients with colorectal cancer (CRC) harboring BRAF mutation have a poor prognosis. The median survival time for patients with advanced BRAFV600E-mutant CRC is only appr Show more
Background
Patients with colorectal cancer (CRC) harboring BRAF mutation have a poor prognosis. The median survival time for patients with advanced BRAFV600E-mutant CRC is only approximately one year. Owing to the insensitivity to standard chemotherapy, there are still no effective and highly specific treatment strategies available in clinical practice for CRC patients with BRAF mutation. Therefore, targeting the BRAFV600E mutation site, researching and exploring novel targeted therapies are essential to improve the survival rate of patients with this CRC subtype.
Aim
This study aims to develop a precise therapeutic system for BRAFV600E CRC, based on the carrier properties of extracellular vesicles (EVs) and gene therapy targeting BRAFV600E.
Method
We first obtained engineered cells capable of stably producing EVs loaded with BRAFV600E nucleic acid drugs (siBRAFV600E). Next, BRAFV600E-mutant and wild-type CRC cell lines, as well as corresponding subcutaneous and metastasis models, were used to evaluate the therapeutic efficacy of EVs-siBRAFV600E and explored the mechanism. Notably, patient-derived xenograft (PDX) models, which share the same molecular characteristics, pathological features, and heterogeneity as patients do, were utilized to further explore the therapeutic efficacy and mechanisms.
Result
EVs-siBRAFV600E specifically inhibited BRAFV600E CRC but didn't affect BRAF wild-type CRC in vitro and vivo. EVs-siBRAFV600E exerts its therapeutic effect by regulating the MEK1/2-ERK1/2 pathway, and it has demonstrated excellent therapeutic efficacy in PDX models.
Conclusion
The therapeutic EVs we constructed are effective and specific for the BRAFV600E-mutant CRC. This study provides a novel strategy for the treatment of CRC patients with BRAFV600E mutation. Show less
Cell lines are invaluable biomedical research tools, and recent literature has emphasized the importance of genotype authentication and characterization. In the present study, 24 out of 27 cell line i Show more
Cell lines are invaluable biomedical research tools, and recent literature has emphasized the importance of genotype authentication and characterization. In the present study, 24 out of 27 cell line identities were confirmed by short tandem repeat profiling. The molecular phenotypes of the 24 colon cancer cell lines were examined, and microsatellite instability (MSI) and CpG island methylator phenotype (CIMP) were determined, using the Bethesda panel mononucleotide repeat loci and two epimarker panels, respectively. Furthermore, the BRAF, KRAS and PIK3CA oncogenes were analyzed for mutations in known hotspots, while the entire coding sequences of the PTEN and TP53 tumor suppressors were investigated. Nine cell lines showed MSI. Thirteen and nine cell lines were found to be CIMP positive, using the Issa panel and the Weisenberger et al. panel, respectively. The latter was found to be superior for CIMP classification of colon cancer cell lines. Seventeen cell lines harbored disrupting TP53 mutations. Altogether, 20/24 cell lines had the mitogen-activated protein kinase pathway activating mutually exclusive KRAS or BRAF mutations. PIK3CA and PTEN mutations leading to hyperactivation of the phosphoinositide 3-kinase/AKT pathway were observed in 13/24 cell lines. Interestingly, in four cell lines there were no mutations in neither BRAF, KRAS, PIK3CA nor in PTEN. In conclusion, this study presents molecular features of a large number of colon cancer cell lines to aid the selection of suitable in vitro models for descriptive and functional research. Show less