Limits...
Comparative transcriptome profiling of an SV40-transformed human fibroblast (MRC5CVI) and its untransformed counterpart (MRC-5) in response to UVB irradiation.

Chang CW, Chen CR, Huang CY, Shu WY, Chiang CS, Hong JH, Hsu IC - PLoS ONE (2013)

Bottom Line: We found that, in response to UVB irradiation, MRC-5 and MRC5CVI commonly up-regulated the expression of oxidative phosphorylation genes.MRC-5 up-regulated the expressions of chromosome condensation, DNA repair, cell cycle arrest, and apoptotic genes, but MRC5CVI did not.Further cell death assays indicated that MRC5CVI was more sensitive than MRC-5 to UVB-induced cell death with increased caspase-3 activation; combining with the transcriptomic results suggested that MRC5CVI may undergo UVB-induced cell death through mechanisms other than transcriptional regulation.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan.

ABSTRACT
Simian virus 40 (SV40) transforms cells through the suppression of tumor-suppressive responses by large T and small t antigens; studies on the effects of these two oncoproteins have greatly improved our knowledge of tumorigenesis. Large T antigen promotes cellular transformation by binding and inactivating p53 and pRb tumor suppressor proteins. Previous studies have shown that not all of the tumor-suppressive responses were inactivated in SV40-transformed cells; however, the underlying cause is not fully studied. In this study, we investigated the UVB-responsive transcriptome of an SV40-transformed fibroblast (MRC5CVI) and that of its untransformed counterpart (MRC-5). We found that, in response to UVB irradiation, MRC-5 and MRC5CVI commonly up-regulated the expression of oxidative phosphorylation genes. MRC-5 up-regulated the expressions of chromosome condensation, DNA repair, cell cycle arrest, and apoptotic genes, but MRC5CVI did not. Further cell death assays indicated that MRC5CVI was more sensitive than MRC-5 to UVB-induced cell death with increased caspase-3 activation; combining with the transcriptomic results suggested that MRC5CVI may undergo UVB-induced cell death through mechanisms other than transcriptional regulation. Our study provides a further understanding of the effects of SV40 transformation on cellular stress responses, and emphasizes the value of SV40-transformed cells in the researches of sensitizing neoplastic cells to radiations.

Show MeSH

Related in: MedlinePlus

A literature-based model of the most discrepant genes.A literature search shows that the most discrepant genes are related to chromosome condensation, DNA repair, cell cycle arrest, and apoptosis (these studies are listed in Text S1). The p53/CDKN1A/pRb pathway and BAX are included to help clarify the results.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3760899&req=5

pone-0073311-g003: A literature-based model of the most discrepant genes.A literature search shows that the most discrepant genes are related to chromosome condensation, DNA repair, cell cycle arrest, and apoptosis (these studies are listed in Text S1). The p53/CDKN1A/pRb pathway and BAX are included to help clarify the results.

Mentions: Combining 489 UVB-regulated genes in MRC-5 and 739 UVB-regulated genes in MRC5CVI resulted in 967 genes (Table 1). By filtering the expression patterns of the 967 genes between the two cell types with a criterion (Pearson correlation smaller than −0.519; detail in Materials and Methods - Identification of the most discrepant genes between the two cell types), 13 genes were identified as the most discrepant genes in response to UVB irradiation. The differential expression patterns of these 13 genes are shown in Figure 2. These 13 genes are related to chromosome condensation, DNA repair, cell cycle arrest, and apoptosis (Figure 3; related literatures are listed in Text S1). Previously we have validated our microarray system by RT-PCR with randomly selected genes, and the results were generally good (with R2 ranged from 0.86 to 0.94) [18], [25]–[26]. To verify the significant gene expression patterns in this study, we further performed RT-PCR analysis for certain UVB-regulated genes, including the transcriptional targets of p53 (GADD45A and CDKN1A), one antioxidant gene (GPX1), and three of the most discrepant genes (MEN1, NCAPH, and IL8). The RT-PCR results validated the microarray data of both cell types (R2 = 0.82 for MRC-5 and R2 = 0.88 for MRC5CVI; see Figure S3).


Comparative transcriptome profiling of an SV40-transformed human fibroblast (MRC5CVI) and its untransformed counterpart (MRC-5) in response to UVB irradiation.

Chang CW, Chen CR, Huang CY, Shu WY, Chiang CS, Hong JH, Hsu IC - PLoS ONE (2013)

A literature-based model of the most discrepant genes.A literature search shows that the most discrepant genes are related to chromosome condensation, DNA repair, cell cycle arrest, and apoptosis (these studies are listed in Text S1). The p53/CDKN1A/pRb pathway and BAX are included to help clarify the results.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3760899&req=5

pone-0073311-g003: A literature-based model of the most discrepant genes.A literature search shows that the most discrepant genes are related to chromosome condensation, DNA repair, cell cycle arrest, and apoptosis (these studies are listed in Text S1). The p53/CDKN1A/pRb pathway and BAX are included to help clarify the results.
Mentions: Combining 489 UVB-regulated genes in MRC-5 and 739 UVB-regulated genes in MRC5CVI resulted in 967 genes (Table 1). By filtering the expression patterns of the 967 genes between the two cell types with a criterion (Pearson correlation smaller than −0.519; detail in Materials and Methods - Identification of the most discrepant genes between the two cell types), 13 genes were identified as the most discrepant genes in response to UVB irradiation. The differential expression patterns of these 13 genes are shown in Figure 2. These 13 genes are related to chromosome condensation, DNA repair, cell cycle arrest, and apoptosis (Figure 3; related literatures are listed in Text S1). Previously we have validated our microarray system by RT-PCR with randomly selected genes, and the results were generally good (with R2 ranged from 0.86 to 0.94) [18], [25]–[26]. To verify the significant gene expression patterns in this study, we further performed RT-PCR analysis for certain UVB-regulated genes, including the transcriptional targets of p53 (GADD45A and CDKN1A), one antioxidant gene (GPX1), and three of the most discrepant genes (MEN1, NCAPH, and IL8). The RT-PCR results validated the microarray data of both cell types (R2 = 0.82 for MRC-5 and R2 = 0.88 for MRC5CVI; see Figure S3).

Bottom Line: We found that, in response to UVB irradiation, MRC-5 and MRC5CVI commonly up-regulated the expression of oxidative phosphorylation genes.MRC-5 up-regulated the expressions of chromosome condensation, DNA repair, cell cycle arrest, and apoptotic genes, but MRC5CVI did not.Further cell death assays indicated that MRC5CVI was more sensitive than MRC-5 to UVB-induced cell death with increased caspase-3 activation; combining with the transcriptomic results suggested that MRC5CVI may undergo UVB-induced cell death through mechanisms other than transcriptional regulation.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan.

ABSTRACT
Simian virus 40 (SV40) transforms cells through the suppression of tumor-suppressive responses by large T and small t antigens; studies on the effects of these two oncoproteins have greatly improved our knowledge of tumorigenesis. Large T antigen promotes cellular transformation by binding and inactivating p53 and pRb tumor suppressor proteins. Previous studies have shown that not all of the tumor-suppressive responses were inactivated in SV40-transformed cells; however, the underlying cause is not fully studied. In this study, we investigated the UVB-responsive transcriptome of an SV40-transformed fibroblast (MRC5CVI) and that of its untransformed counterpart (MRC-5). We found that, in response to UVB irradiation, MRC-5 and MRC5CVI commonly up-regulated the expression of oxidative phosphorylation genes. MRC-5 up-regulated the expressions of chromosome condensation, DNA repair, cell cycle arrest, and apoptotic genes, but MRC5CVI did not. Further cell death assays indicated that MRC5CVI was more sensitive than MRC-5 to UVB-induced cell death with increased caspase-3 activation; combining with the transcriptomic results suggested that MRC5CVI may undergo UVB-induced cell death through mechanisms other than transcriptional regulation. Our study provides a further understanding of the effects of SV40 transformation on cellular stress responses, and emphasizes the value of SV40-transformed cells in the researches of sensitizing neoplastic cells to radiations.

Show MeSH
Related in: MedlinePlus