Deletion and down-regulation of SMAD4 gene in colorectal cancers in a Chinese population

• 作 者: Yanling Ma Fei Yan Li Li Li Liu Jianhai Sun
• 机 构: Department of Oncology,Zhongshan Hospital,Wuhan University,
• 出 处: Chinese Journal of Cancer Research
• 发表日期: 2014年05期
• 关键词: colorectal carcinogenesis populations paired pathogenesis alone suppressor frequ

Objective: Colorectal cancer(CRC) is one of the most common types of human cancers. As a tumor suppressor, SMAD4 plays a key role in colorectal carcinogenesis and invasiveness. Copy number variations(CNVs) of the SMAD4 gene have been reported to be associated with cancer pathogenesis in array-based studies in different populations. Here we aimed to investigate the CNVs of the SMAD4 gene in a relatively large number of CRC patients from China. Methods: In the present study, we collected 147 Chinese CRC tumors as well as self-paired normal control tissues. Quantitative PCR was carried out to examine the copy number as well as the m RNA expression of the SMAD4 gene. Results: Our results showed that the copy number deletions of SMAD4 were frequent in a relatively high percentage of CRC samples(34.7%, 51 out of 147). There was a positive correlation between the copy number decrease of SMAD4 and tumor progression in CRCs. Furthermore, copy number loss of SMAD4 was correlated with decreased m RNA expression.Conclusions: These findings suggested that the copy number deletions of SMAD4 were frequent in CRC patients from China and had the potential to serve as a diagnostic indicator, alone or in combination with other markers, for CRC.

As a tumor suppressor, SMAD4 plays a key role in colorectal carcinogenesis and invasiveness. Copy number variations (CNVs) of the SMAD4 gene have been reported to be associated Here we aimed to investigate the CNVs of the SMAD4 gene in a relatively large number of CRC patients from China. Methods: In the present study, we collected 147 Chinese CRC tumors as well as Self-paired normal control tissues. Quantitative PCR was carried out to examine the copy number as well as the m RNA expression of the SMAD4 gene. Results: Our results showed that the copy number deletions of SMAD4 were frequent in a relatively high percentage of CRC There was a positive correlation between the copy number decrease of SMAD4 and tumor progression in CRCs. Furthermore, copy number loss of SMAD4 was correlated with decreased m RNA expression.Conclusions: These findings suggested that the copy number deletions of SMAD4 were frequent in CRC patients from China and had the potential to serve as a diagnostic indicator, alone or in combination with other markers, for CRC.