Abstract Backgrounds however, CR-iCCA cell lines showed high UBQLN4 expression concomitant with increased phosphorylated ATM (pATM). Moreover, 3D spheroid assay revealed UBQLN4 and pATM are expressed significantly higher in CR-iCCA cell lines than respective parental cell lines. In clinically annotated iCCA specimens, non-responders to neoadjuvant chemotherapy including cisplatin had increased UBQLN4 and pATM protein levels in iCCA tissues as assessed by multiplex immunofluorescence, supporting that FuiCCA cohorts showed high UBQLN4 and pATM protein levels lead to worse prognosis (p=0.049). Conclusions: Upregulated UBQLN4 expression correlates with postoperative recurrence as well as resistance to cisplatin in iCCA patients, indicating that UBQLN4 is a strong prognostic biomarker related to cisplatin treatment of iCCA patients. Citation Format: Kodai Abe, Kelly K. Chong, Yuta Abe, Minoru Kitago, Motonori Edanami, Yosuke Uematsu, Yohei Masugi, Akihisa Ueno, Anton Bilchik, Yosef Shiloh, Yuko Kitagawa, Dave Hoon. Clinical significance of elevated UBQLN4 expression with resistance to cisplatin in intrahepatic cholangiocarcinoma abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 7900.
Abe et al. (Fri,) studied this question.