This study explored the role of lymphocyte antigen 6 family member D (LY6D) in colon cancer stem cells’ (CCSCs) proliferation and invasion. LY6D was knocked down using siRNA, and the down-regulation of LY6D was verified using Western blotting. After LY6D knockdown, CCSCs’ proliferation, stemness, and invasion were suppressed, whereas apoptosis was increased. Gene Ontology (GO) enrichment analysis revealed that the differentially expressed genes (DEGs) between siLY6D and the negative control groups were significantly enriched in the cell–substrate adherens junction, focal adhesion, and cell–substrate junction terms. Meanwhile, the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that the DEGs were significantly enriched in the MAPK pathway. In addition, Western blotting results showed that pBRAF and pERK1/2, cascade kinases of the MAPK pathway, were significantly down-regulated after LY6D knockdown. In addition, nude mice xenograft experiments showed that the siLY6D treatment decreased tumor sizes and weights and improved tumor-bearing mice survival rates compared with the control group. In conclusion, these findings indicate that LY6D, which is highly expressed in CCSCs, is a key factor involved in tumor growth and development and might be a potential cancer marker and therapeutic target for colon cancer.

Cervical cancer remains a major threat to women’s health, with advanced cases often exhibiting recurrence and metastasis due to cancer stem cells driving therapy resistance. This study evaluated fenbendazole (FBZ), a repurposed veterinary anthelmintic, for its antitumor activity dual targeting cervical cancer cells (CCCs) and cervical cancer stem cells (CCSCs). CD133⁺CD44⁺ CCSCs were isolated from HeLa and C-33 A cell lines via immunomagnetic sorting and validated for stemness. Cell proliferation, cell cycle and apoptosis, and protein expression were detected by MST assay, flow cytometry, and Western blot analysis, respectively. FBZ dose-dependently inhibited proliferation, induced G2/M arrest, and triggered apoptosis in both CCCs and CCSCs. Mechanistically, FBZ upregulated cyclin B1 and phosphorylation of cdc25C-Ser198, while downregulating Wee1, phosphorylation of CDK1, and phosphorylation of cdc25C-Ser216, collectively enforcing G2/M blockade. In vivo, FBZ (100 mg/kg) significantly suppressed tumor growth in xenograft models without weight loss, contrasting with cisplatin-induced toxicity. Survival analysis revealed 100% survival in FBZ-treated mice versus 40% in cisplatin and 0% in untreated controls. These findings demonstrate FBZ’s unique ability to simultaneously target bulk tumor cells and therapy-resistant CCSCs via cell cycle disruption, supported by its preclinical safety and efficacy, positioning it as a promising therapeutic candidate for cervical cancer.

Lymphocyte antigen 6 complex, locus K (LY6K) is a putative oncogene in various human cancers, including colorectal cancer, where elevated expression is associated with poor prognosis. This study investigates the antitumor effects of LY6K in colon cancer stem cells (CCSCs) both in vitro and in vivo. EpCAM and CD44 surface markers were used to isolate CCSCs from HCT116 cells, and the expression of LY6K in CCSCs was analyzed by real-time PCR. RNA interference was used to silence LY6K to evaluate its potential role of LY6K on the proliferation, migration, invasion, and cell cycle of CCSCs. Functional assays, including MTS assays, flow cytometric analyses, Transwell migration and invasion assays, and a xenograft model, were used for analysis. The results revealed that LY6K was highly expressed in CCSCs. siRNA-mediated LY6K-silencing in CCSCs inhibited cell proliferation by inducing G1 phase cell cycle arrest and suppressed migration and invasion. In vivo, LY6K silencing effectively reduced tumor growth and extended survival in a mouse model. These findings suggest LY6K as a promising therapeutic target for eradicating CCSCs in colorectal cancer treatment.

Prostate stem cell antigen (PSCA), a pivotal member of the lymphocyte antigen-6 (Ly6) protein family, has been implicated in the tumorigenesis and neoplastic progression of diverse cancer types. In this study, we conducted a thorough investigation into the role of PSCA in the development of colorectal cancer (CRC). Survival analysis based on The Cancer Genome Atlas (TCGA) dataset demonstrated that elevated expression of PSCA was tightly correlated with unfavorable overall survival, inferior relapse-free survival, and worse post-progression survival among CRC patients. Additionally, PSCA exhibited significantly higher expression levels in colorectal cancer stem cell (CRC-SCs) relative to CRC cell lines. Loss-of-function assays using small interfering RNA (siRNA)-mediated silencing were performed to evaluate the effects of PSCA downregulation on the stemness properties of CRC-SCs, including proliferative capacity, invasive potential, and apoptotic rate, which were assessed by MTS assay, transwell invasion assay, and flow cytometry analysis, respectively. The results showed that silencing PSCA markedly suppressed the proliferation and invasion of CRC-SCs, while significantly promoting cellular apoptosis. RNA sequencing was performed to identify differentially expressed genes (DEGs) in the PSCA knockdown group compared to the negative control group. Follow-up analyses using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) indicated that these DEGs were significantly enriched in the cell-substrate adherens junction term and the mitogen-activated protein kinase 9MAPK signaling pathway. Moreover, PSCA silencing substantially reduced the phosphorylation levels of the core MAPK signaling constituents, pBRAF and pERK1/2; conversely, PSCA overexpression prominently upregulated the expression of pBRAF and pERK1/2. In nude mice with CRC-SCs cancer xenograft tumors, treatment with PSCA siRNA significantly decreased tumor volume and weight, while also notably extending the survival time of the tumor-bearing mice compared to the control group. Collectively, these findings confirm that PSCA plays a critical oncogenic role in CRC cancer growth and malignant progression, suggesting its potential as a novel and promising therapeutic target for CRC.