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Azmi, A. S.

Publications and source records attributed to Azmi, A. S..

2 recordsLinked to original sources
bioRxiv2022

Molecular profiling of XPO1 inhibitor and gemcitabine-nab-paclitaxel combination in cellular and LSL-Kras G12D/+; Trp53 fl/+; Pdx1-Cre (KPC) pancreatic cancer model

The majority of pancreatic ductal adenocarcinoma (PDAC) patients experience disease progression while on treatment with gemcitabine and nab-Paclitaxel (GemPac) treatment indicating the need for more effective combinations for this recalcitrant disease. Earlier we showed that nuclear exporter protein exportin 1 (XPO1) is a valid therapeutic target in PDAC and the selective inhibitor of nuclear export (SINE) selinexor (Sel), synergistically enhances the efficacy of GemPac in pancreatic cancer cells, spheroids, patient derived tumors and had promising activity in a phase I study in patients with PDAC. Here we investigated the mechanisms of synergy by molecular profiling of Sel or Sel-GemPac treated PDAC cells, in vitro and by utilizing genetically modified LSL-Kras G12D/+; Trp53 fl/+; Pdx1-Cre (KPC) mouse model. In KPC model, Sel given with GemPac at a sub-MTD dose enhanced the survival compared to controls (p < 0.05). Molecular analysis of residual KPC tumors showed re-organization of tumor stromal architecture, suppression of proliferation and nuclear retention of tumor suppressors. Single cell nuclear RNA sequencing (snRNAseq) revealed significant loss of cellular clusters in the Sel-GemPac treated mice including CD44 stem cell population. RNA-seq, Gene Ontology (GO) and Gene Set Enrichment Analysis (GSEA) analysis showed inhibition of several tumor promoting molecules. Prioritized RNA-seq identified molecules were validated in in vitro or in the PDAC patient samples through siRNA mediated silencing, quantitative gene expression, cytotoxicity assays and confirmed their role in observed synergy. Sel or Sel-GemPac caused broad penetration in PDAC supporting signaling networks.

cancer biology↗
bioRxiv2022

Inhibitor of the nuclear transport protein XPO1 enhances the anticancer efficacy of KRAS G12C inhibitors in preclinical models of KRAS G12C mutant cancers

The identification of molecules that can bind covalently to KRAS G12C and lock it in an inactive GDP-bound conformation has opened the door to targeting KRAS G12C selectively. These agents have shown promise in preclinical tumor models and clinical trials. FDA has recently granted approval to sotorasib for KRAS G12C mutated non-small cell lung cancer (NSCLC). However, patients receiving these agents as monotherapy may not respond and generally develop drug resistance over time. This necessitates the development of multi-targeted approaches that can potentially sensitize tumors to KRAS inhibitors. We generated KRAS G12C inhibitor-resistant cell lines and observed that they exhibit sensitivity toward selinexor, a selective inhibitor of nuclear export protein exportin1 (XPO1), as a single agent. KRAS G12C inhibitor MRTX1257 in combination with selinexor suppressed the proliferation of KRAS G12C mutant cancer cell lines MiaPaCa-2 and NCI-H2122 in a synergistic manner. Moreover, combined treatment of selinexor with KRAS G12C inhibitors resulted in enhanced spheroid disintegration, reduction in the number and size of colonies formed by G12C mutant cancer cells. A combination of selinexor with KRAS G12C inhibitors potentiated the inhibition of KRAS expression in MiaPaCa-2 cells. NF-kB protein expression was also markedly reduced by selinexor and MRTX1257 combination. In an in vivo KRAS G12C cell-derived xenograft model, oral administration of a combination of selinexor and sotorasib was demonstrated to reduce tumor burden and enhance survival. In conclusion, we have shown that the nuclear transport protein XPO1 inhibitor can enhance the anticancer activity of KRAS G12C inhibitors in preclinical cancer models. SignificanceIn this study, combining nuclear transport inhibitor selinexor with KRAS G12C inhibitors has resulted in potent antitumor effects in preclinical cancer models. This can be an effective combination therapy for cancer patients that do not respond or develop resistance to KRAS G12C inhibitor treatment.

cancer biology↗