hnRNPLL regulates MYOF alternative splicing and correlates with early metastasis in pancreatic ductal adenocarcinoma

Cancer Lett. 2024 Dec 30:217436. doi: 10.1016/j.canlet.2024.217436. Online ahead of print.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) is a deadly cancer known for its high rate of early metastasis, necessitating the discovery of the underlying mechanisms. Herein, we report that heterogeneous nuclear ribonucleoprotein L-like (hnRNPLL) expression significantly increases at the invasion forefront in PDAC and is associated with early metastasis and poor prognosis. Our findings revealed that hnRNPLL knockdown resulted in extensive exon skipping (ES) events. In particular, we identified myoferlin (MYOF), a member of the ferlin family involved in membrane processes, as a functional splicing target of hnRNPLL. hnRNPLL depletion stimulates MYOF exon 17 retention to reduce the short isoform of MYOF (MYOFb) and inhibit metastasis. In contrast, hnRNPLL or MYOFb overexpression promoted pancreatic cancer cell migration and invasion. These results suggest that hnRNPLL is a critical factor for early PDAC metastasis. hnRNPLL and MYOFb may be potential therapeutic targets for PDAC.

Keywords: MYOF; alternative splicing; early metastasis; hnRNPLL; pancreatic ductal adenocarcinoma.