Abstract
Gastric-type adenocarcinoma (GAS) of the uterine cervix is a rare and aggressive subtype of cervical adenocarcinoma characterized by intrinsic resistance to chemotherapy and poor clinical outcomes due to the lack of effective treatment options. To address this critical unmet need, we established a novel GAS-derived cell line, KGAS, from ascitic fluid collected from a patient with recurrent GAS. Short tandem repeat (STR) analysis confirmed the genetic identity between the primary tumor and the cell line. Upon transplantation into immunocompromised mice, KGAS cells formed tumors that expressed Claudin-18 and MUC6, clinically recognized markers of GAS. Furthermore, KGAS cells exhibited marked resistance to paclitaxel and carboplatin, showing significantly reduced growth inhibition compared to HeLa cells. We also established a paclitaxel- and carboplatin-resistant subline, rKGAS, and performed microRNA (miRNA) sequencing to explore the molecular basis of acquired chemoresistance. Seventeen differentially expressed miRNAs were identified between KGAS and rKGAS cells. Upregulated miRNAs in rKGAS were predicted to target oncogenes such as BCL2, MET, SIRT1, and VEGFA, whereas downregulated miRNAs were associated with tumor suppressor genes, including IGF1R, TNFAIP3, and MTOR. The KGAS and rKGAS cell lines represent valuable preclinical models for elucidating the molecular mechanisms of chemoresistance and malignant progression in cervical GAS, and may contribute to the development of novel therapeutic strategies for this challenging cancer subtype.