Mutational Analysis of Pro-apoptotic BAD Gene in Nonsmall Cell Lung Cancer

PURPOSE : Evidence exists that deregulation of apoptosis is involved in the mechanisms of cancer development, and the somatic mutations of apoptosisrelated genes have been reported in human cancers. Bcl- XL/Bcl-2-associated death promoter (BAD), a pro-apoptotic member of Bcl-2 family, plays an important role in the intrinsic apoptosis pathway. MATERIALS AND METHODS : To explore the possibility that the genetic alterations of BAD might be involved in the development of human cancers, we analyzed the entire coding region and all splice sites of human BAD gene in 100 human non-small cell lung cancers (NSCLC) by polymerase chain reaction (PCR)-based single-strand conformation polymorphism (SSCP). RESULTS : The PCR-SSCP analysis detected no mutation in the entire coding regions and all splice sites of human BAD gene in the 100 NSCLCs. CONCLUSION : The data presented here suggested that BAD gene mutation may not contribute to the pathogenesis of human NSCLCs

Pro-apoptotic Cytochrome c Gene Mutation is Rare in Non-small Cell Lung Cancers

PURPOSE: Several lines of evidence have indicated that the deregulation of apoptosis is involved in the mechanisms of cancer development, and somatic mutations of the apoptosis-related genes have been reported in human cancers. In addition to its role in oxidative phosphorylation, release of cytochrome c from the mitochondrial intermembrane space results in nuclear apoptosis. The aim of this study was to explore whether alteration of cytochrome c gene mutation is a characteristic of human non-small cell lung cancers (NSCLC). MATERIALS AND METHODS: In the current study, to detect the somatic mutations in the DNA sequences encoding cytochrome c in 48 NSCLCs, we used polymerase chain reaction (PCR), single-strand conformation polymorphism (SSCP), and DNA sequencing. RESULTS: The SSCP analysis revealed no mutation in the entire coding regions and all splice sites of human cytochrome c gene in the 48 NSCLCs. CONCLUSION: The data presented here indicate that the pro-apoptotic cytochrome c may not be somatically mutated in human NSCLCs, and suggest that NSCLCs may not utilize mutational events of cytochrome c gene in the mechanisms for evading apoptosis.

Mutational Analysis of Caspase-7 and 8 Genes in Non-small Cell Lung Cancer

PURPOSE : Several lines of evidence have indicated that deregulation of apoptosis is involved in the mechanism of cancer development. Caspase-8 activation plays a central role in the initiation phase of apoptosis, while caspase-7 is one of the main execution phase caspases of apoptosis. The aim of this study was to explore the possibility that genetic alterations of the caspase-8 and caspase-7 genes are involved in the development of human non-small cell lung cancer (NSCLC). MATERIALS AND METHODS : We have analyzed the entire coding region of both the caspase-7 and caspase-8 genes to detect the somatic mutations in 100 NSCLCs by using polymerase chain reaction (PCR)- single strand conformation polymorphism (SSCP). RESULTS : The PCR-SSCP analysis detected no mutations in the entire coding regions of both the caspase-7 and caspase-8 genes in the NSCLCs. CONCLUSION : The data presented here suggests that both the caspase-7 and caspase-8 genes may not be somatically mutated in human NSCLCs

Mutational Analysis of Proapoptotic bcl-2 Family genes in Colon Carcinomas

BACKGROUND: Several lines of evidence have indicated that the deregulation of apoptosis is involved in the mechanisms of cancer development, and somatic mutations of the apoptosisrelated genes have been reported in human cancers. Members of the bcl-2 family proteins regulate the intrinsic apoptosis pathway mainly in the mitochondria. The aim of this study was to explore whether the somatic mutation of the proapoptotic bcl-2 family genes, one of the mechanisms that prolong the survival of cancer cells, occurred in colorectal carcinomas. METHODS: In the current study, to detect the somatic mutations in the DNA sequences encoding the bcl-2 homology 3 (BH3) domain of the human bak, bid, bik, bim, PUMA, bcl-rambo, bcl-G, and bmf genes in 98 colon adenocarcinomas, we used polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP), and DNA sequencing. RESULTS: The SSCP analysis detected no evidence of somatic mutations of the genes in the coding regions of the BH3 domain in the cancers. CONCLUSIONS: The data presented here indicate that the proapoptotic bcl-2 family genes, bak, bid, bik, bim, PUMA, bcl-rambo, bcl-G and bmf may not be somatically mutated in human colorectal carcinomas, and suggest that the colorectal cancers may not utilize mutational events of these proapoptotic bcl-2 family genes in the mechanisms for evading apoptosis.

Mutational Analysis of the Epidermal Growth Factor Receptor Gene in Gastrointestinal Stromal Tumors

PUPOSE: Most gastrointestinal stromal tumors (GISTs) have gain-of-function mutations of the KIT or the platelet-derived growth factor receptor alpha (PDGFRA) genes, but approximately 10% of the GISTs are wild types for both the KIT and the PDGFRA genes. The purpose of this study was to investigate the possibility that epidermal growth factor receptor (EGFR) gene mutation might be responsible for the pathogenesis of GIST. MATERIALS AND METHODS: We analyzed the EGFR gene in 60 GISTs for the detection of somatic mutations by using the polymerase chain reaction (PCR), the single strand conformation polymorphism (SSCP), and DNA sequencing in exon 18, 19, and 21 encoding the kinase domain. RESULTS: The SSCP analysis revealed no evidence of EGFR mutations in exon 18, 19, and 21 in GISTs. CONCLUSION: The data indicate that the EGFR gene may not be mutated in human GIST and suggest that therapies targeting the mutated EGFR gene products might not be useful in the treatment of GISTs.

Mutational Analysis of Proapoptotic Bcl-2 Family Members in Gastric Carcinomas

PURPOSE: Evidence exists that dysregulation of Bcl-2 family members is involved in the pathogenesis of cancer development. The aim of this study was to explore whether the somatic mutation of proapoptotic Bcl-2 member genes, one of the mechanisms that prolong the survival of cancer cells, is involved in gastric carcinogenesis. MATERIALS AND METHODS: In the current study, to detect somatic mutations of the DNA sequences encoding the Bcl-2 homology 3 (BH3) domain of the human BAD, BIM, BIK, and Bcl-G genes in 60 advanced gastric adenocarcinomas, we used the polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP), and DNA sequencing. RESULTS: The SSCP analysis revealed no mutations in the coding regions of the BH3 domain in the cancers. CONCLUSION: The data presented here indicate that proapoptotic Bcl-2 member genes, BAD, BIM, BIK, and Bcl-G, may not be mutated in human gastric carcinomas and suggest that these genes might be altered by mechanisms other mechanisms somatic mutation.