Dataset Information

The CaSm (LSm1) oncogene promotes transformation, chemoresistance, and metastasis of pancreatic cancer cells

ABSTRACT: The Cancer associated Sm-like (CaSm) oncogene is overexpressed in 87% of human pancreatic tumor samples and CaSm knockdown has demonstrated therapeutic efficacy in murine models of pancreatic cancer. Evidence indicates that CaSm modulates mRNA degradation; however, its target genes and the mechanisms by which CaSm promotes pancreatic cancer remain largely unknown. Here, we demonstrate that the CaSm overexpression alters several hallmarks of cancer – including transformation, proliferation, chemoresistance, and metastasis. Doxycycline-induced CaSm expression enhanced proliferation and both anchorage-dependent and -independent growth of the human Panc-1 cells in vitro. CaSm induction decreased gemcitabine-induced cytotoxicity and altered the expression of apoptotic regulation genes, including Bad, E2F1, and Bcl-XL. CaSm-overexpressing Panc-1 cells were 2-fold more migratory and 4-fold more invasive than the driver controls and demonstrated characteristics of epithelial-to-mesenchymal transition such as morphological changes and decreased E-cadherin expression. CaSm induction resulted in changes in RNA expression of metastasis-associated genes such as MMP1, SerpinB5, uPAR, and Slug. Using a murine model of metastatic pancreatic cancer, injection of CaSm-induced Panc-1 cells resulted in a higher abundance of hepatic metastatic lesions. Overall, CaSm overexpression contributed to a more aggressive cancer phenotype in Panc-1 cells, further supporting the use of CaSm as a therapeutic target against pancreatic cancer.

ORGANISM(S): Homo sapiens

PROVIDER: GSE74319 | GEO | 2015/10/24

SECONDARY ACCESSION(S): PRJNA299658

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:The Cancer associated Sm-like (CaSm) oncogene is overexpressed in 87% of human pancreatic tumor samples and CaSm knockdown has demonstrated therapeutic efficacy in murine models of pancreatic cancer. Evidence indicates that CaSm modulates mRNA degradation; however, its target genes and the mechanisms by which CaSm promotes pancreatic cancer remain largely unknown. Here, we demonstrate that the CaSm overexpression alters several hallmarks of cancer â including transformation, proliferation, chemoresistance, and metastasis. Doxycycline-induced CaSm expression enhanced proliferation and both anchorage-dependent and -independent growth of the human Panc-1 cells in vitro. CaSm induction decreased gemcitabine-induced cytotoxicity and altered the expression of apoptotic regulation genes, including Bad, E2F1, and Bcl-XL. CaSm-overexpressing Panc-1 cells were 2-fold more migratory and 4-fold more invasive than the driver controls and demonstrated characteristics of epithelial-to-mesenchymal transition such as morphological changes and decreased E-cadherin expression. CaSm induction resulted in changes in RNA expression of metastasis-associated genes such as MMP1, SerpinB5, uPAR, and Slug. Using a murine model of metastatic pancreatic cancer, injection of CaSm-induced Panc-1 cells resulted in a higher abundance of hepatic metastatic lesions. Overall, CaSm overexpression contributed to a more aggressive cancer phenotype in Panc-1 cells, further supporting the use of CaSm as a therapeutic target against pancreatic cancer. Tet-on driver and tet-on CaSm Panc-1 cells were grown with and without doxycycline (1 Î¼g/mL) for 4 weeks. Levels of CaSm expression were confirmed using RT-PCR (Supplementary Figure 2a). RNA isolation was performed using RNeasy Plus kit (Qiagen, Valencia, CA) following the manufacturerâs protocols. The Hollings Cancer Center Tissue Biorepository core facility confirmed RNA quality using the 18S/28S Ratio Integrity Number using Agilent 2100 Bioanalyzer (Agilent Technologies, Santa Clara, CA); RNA with a RIN of 10 was used for further analysis (Supplementary Figure 2b). Complement DNA synthesis was performed using RT2 First Strand kit and RT2 SYBR Green qPCR master mix was used for the microarray master mix reagent according to the manufacturerâs manual (SABiosciences). The Cancer PathwayFinder PCR array (SABiosciences) was run on the Roche 480 Lightcycler (Roche, Indianapolis, IN) with 2 plates run for each tet-on driver + doxycycline, tet-on CaSm, and tet-on CaSm + doxycycline. The plates included controls for genomic DNA contamination, reverse transcription, and positive controls. Analysis was performed using SABioscienceâs Free PCR Array Data Analysis Software (ÎÎCt method) with B2M, HPRT1, and GAPDH as pooled housekeeping genes.

Project description:Purpose: Chemotherapy is pivotal in the multimodal treatment of pancreatic cancer patients. In recent years, technical advances have developed experimental methods that unveiled a high degree of inter- and intratumoral heterogeneity in pancreatic cancer. We hypothesized that intratumoral heterogeneity (ITH) impacts response to gemcitabine treatment and demands specific targeting of resistant subclones. Experimental Design: We addressed the effect of ITH on response to gemcitabine treatment using single cell-derived cell lines (SCDCL) from the classical-like cell line BxPC3 and the basal-like cell line Panc-1 which were analyzed by mRNA-seq and mass spectrometry. Results: Individual SCDCLs of the parental tumor cell populations of BxPC3 and Panc-1 showed considerable heterogeneity in response to gemcitabine. Unsupervised principal component analysis (PCA) including the 1,000 most variably expressed genes showed a clustering of the SCDCLs according to their respective sensitivity to gemcitabine treatment for BxPC3, while this clustering was less clear for Panc-1. In BxPC3 SCDCLs, enriched signaling pathways EMT, TNF signaling via NfKB, and IL2STAT5 signaling correlated with more resistant behavior to gemcitabine. In Panc-1 SCDCLs MYC targets V1 and V2 as well as E2F targets were associated with stronger resistance to gemcitabine. Feature extraction of proteomes again identified less proteins whose expression was associated with the response of individual SCDCLs in Panc-1 compared to BxPC3. Based on molecular profiles, we could show that the gemcitabine-resistant SCDCLs of both BxPC3 and Panc-1 are more sensitive to the BET inhibitor JQ1 compared to the respective gemcitabine-sensitive SCDCLs. Conclusions: Our model system of SCDCLs identified gemcitabine-resistant subclones within a parental tumor population and provides evidence for the critical role of ITH for treatment response in pancreatic cancer. Through molecular profiling, we identified specific signaling pathways and protein signatures that might help to explain the differential response to treatment among clones. We exploited these molecular differences for an improved and more targeted therapy of resistant subclones of a heterogeneous tumor.

Dataset Information

The CaSm (LSm1) oncogene promotes transformation, chemoresistance, and metastasis of pancreatic cancer cells

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure