Transcriptional Profiling Identifies Gene Expression Changes Associated with IFN-α Tolerance in Hepatitis C–Related Hepatocellular Carcinoma Cells

Autor: Nathalie Wong, Kathy Y-Y. Chan, Pascale F. Macgregor, Paul B-S. Lai, Jeremy A. Squire, Ben Beheshti, Monique Albert, Thomas W-T. Leung
Rok vydání: 2005
Předmět:
Zdroj: Clinical Cancer Research. 11:1319-1326
ISSN: 1557-3265
1078-0432
DOI: 10.1158/1078-0432.1319.11.3
Popis: Purpose: Treatment with IFN-α therapy has been shown to exhibit antitumor effects on patients with hepatocellular carcinoma (HCC). However, individual responses remained unpredictable because of the frequent presence of intrinsic or acquired IFN-α resistance. Hence, delineation of molecular targets implicated in the resistant pathway holds value in refining the therapeutic benefits of IFN-α. Experimental Design: The current study analyzed the effect of IFN-α in human HCC cells. Three hepatitis C virus (HCV)–related, five hepatitis B virus (HBV)–related and two non-B non-C–related cell lines were subjected to IFN-α treatment and the cytotoxic effect on cell viability was measured. Further analysis by cDNA microarray and quantitative reverse transcription-PCR were conducted to examine the gene expression changes that mediated the IFN-α resistance observed. Results: According to the IC50 values determined, HCV-related cell lines indicated distinct resistance (IC50, 389-1468 units/mL) compared with the HBV-related (IC50, 11-77 units/mL) and non-B non-C–related cell lines (IC50, 24-108 units/mL). Unsupervised hierarchical clustering on array data indicated three HCV-related cell lines to cluster independently from the sensitive cell lines, suggesting discrete features in association with IFN-α tolerance. Moreover, Significance Analysis of Microarrays analysis indicated the differential expression of 149 expressed sequence tags that represented 51 up-regulated and 98 down-regulated genes in the resistant cell lines. Comparing the temporal pattern of gene expression between 6- and 24-hour treatments, candidate genes that were considerably induced with time were further highlighted in the tolerant HCV-related cell lines. These candidates were verified by quantitative reverse transcription-PCR, which confirmed the down-regulation of UBA2, ZNF185, and FOXF1 and up-regulation of UBE4B in the drug-tolerant cells. Conclusions: Our present study showed that the insensitivity to IFN-α therapy in HCC cells is associated with drug-inducible transcriptional alterations. Furthermore, our investigation highlighted potential candidate genes in conferring an anti-apoptotic effect toward IFN-α treatment.
Databáze: OpenAIRE
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