RCC1 regulation of subcellular protein localization via Ran GTPase drives pancreatic ductal adenocarcinoma growth

Cancer Lett. 2024 Nov 1:604:217275. doi: 10.1016/j.canlet.2024.217275. Epub 2024 Sep 24.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy, with limited therapeutic options. Here, we evaluated the role of regulator of chromosome condensation 1 (RCC1) in PDAC. RCC1 functions as a guanine exchange factor for GTP-binding nuclear protein Ran (Ran) GTPase and is involved in nucleocytoplasmic transport. RCC1 RNA expression is elevated in PDAC tissues compared to normal pancreatic tissues and correlates with poor prognosis. RCC1 silencing by RNAi and CRISPR-Cas9 knockout (KO) results in reduced proliferation in 2-D and 3-D cell cultures. RCC1 knockdown (KD) reduced migration and clonogenicity, enhanced apoptosis, and altered cell cycle progression in human PDAC and murine cells from LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx1-Cre (KPC) tumors. Mechanistically, RCC1 KO shows widespread transcriptomic alterations including regulation of PTK7, a co-receptor of the Wnt signaling pathway. RCC1 KD disrupted subcellular Ran localization and the Ran gradient. Nuclear and cytosolic proteomics revealed altered subcellular proteome localization in Rcc1 KD KPC-tumor-derived cells and several altered metabolic biosynthesis pathways. In vivo, RCC1 KO cells show reduced tumor growth potential when injected as sub-cutaneous xenografts. Finally, RCC1 KD sensitized PDAC cells to gemcitabine chemotherapy treatment. This study reveals the role of RCC1 in pancreatic cancer as a novel molecular vulnerability that could be exploited to enhance therapeutic response.

Keywords: Nuclear export; PDAC; Pancreatic cancer; RCC1; Ran GTPase.

MeSH terms

  • Animals
  • Apoptosis
  • Carcinoma, Pancreatic Ductal* / genetics
  • Carcinoma, Pancreatic Ductal* / metabolism
  • Carcinoma, Pancreatic Ductal* / pathology
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism
  • Cell Line, Tumor
  • Cell Movement
  • Cell Proliferation*
  • Deoxycytidine / analogs & derivatives
  • Deoxycytidine / pharmacology
  • Gemcitabine
  • Gene Expression Regulation, Neoplastic
  • Guanine Nucleotide Exchange Factors* / genetics
  • Guanine Nucleotide Exchange Factors* / metabolism
  • Humans
  • Mice
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Pancreatic Neoplasms* / genetics
  • Pancreatic Neoplasms* / metabolism
  • Pancreatic Neoplasms* / pathology
  • ran GTP-Binding Protein* / genetics
  • ran GTP-Binding Protein* / metabolism

Substances

  • ran GTP-Binding Protein
  • RCC1 protein, human
  • Guanine Nucleotide Exchange Factors
  • RAN protein, human
  • Cell Cycle Proteins
  • Deoxycytidine
  • Gemcitabine
  • Nuclear Proteins