Institute of Human Genetics, University of Aarhus, Aarhus C, Denmark.
Cancer Epidemiol Biomarkers Prev. 2011 Feb;20(2):397-407. doi: 10.1158/1055-9965.EPI-10-0514. Epub 2010 Dec 6.
Identification of specific mutation targets in cancer may lead to discovery of the genes modulating cancer susceptibility and/or prognosis. The RGSL1, RGS16, and RGS8 genes within the 1q25.3 region belong to the novel family of regulators of G protein signaling (RGS) genes, which increase the GTPase activity of the Gα subunit to attenuate signaling from the G protein-coupled receptor. We evaluated the use of high-resolution melting (HRM) to screen for mutations in the genes of interest and assess their clinical significance.
The HRM analysis was used to screen 32 coding exons of RGSL1, RGS16, and RGS8 in tumors from 200 breast cancer patients. All sequence variants detected by HRM resulted in abnormal shape of the melting curves. The identified mutations and known single nucleotide polymorphisms (SNP) were subsequently confirmed by sequencing, and distribution of the SNP genotypes was determined by SNaPshot analysis. A case-control analysis of genotype frequencies was carried out.
We identified three tumor specific missense mutations in RGSL1 (ex6 c.664 G>A (Val222Ile), ex13 c.2262 C>G (Asp754Glu), and ex13 c.2316 C>T (Ser772Leu) in three different breast cancer patients. In addition, a total of seven known SNPs were identified in this study. Genotype distributions were not significantly different between breast cancer patients and controls.
Identification of novel mutations within RGSL1 provides a new insight into the pathophysiology of breast cancer. Moreover, the HRM analysis represents a reliable and highly sensitive method for mutation scanning of multiple exons.
鉴定癌症中特定的突变靶标可能会发现调节癌症易感性和/或预后的基因。1q25.3 区域内的 RGSL1、RGS16 和 RGS8 基因属于新型 G 蛋白信号转导调节因子（RGS）基因家族，可增加 Gα亚基的 GTPase 活性，从而减弱 G 蛋白偶联受体的信号转导。我们评估了使用高分辨率熔解（HRM）筛选目的基因中的突变并评估其临床意义。
使用 HRM 分析筛选 200 例乳腺癌患者肿瘤中 RGSL1、RGS16 和 RGS8 的 32 个编码外显子。HRM 检测到的所有序列变异均导致熔解曲线形状异常。通过测序确认鉴定的突变和已知单核苷酸多态性（SNP），并通过 SNaPshot 分析确定 SNP 基因型的分布。进行了基因型频率的病例对照分析。
我们在 3 位不同的乳腺癌患者中发现了 RGSL1 中的三个肿瘤特异性错义突变（外显子 6 c.664 G>A（Val222Ile）、外显子 13 c.2262 C>G（Asp754Glu）和外显子 13 c.2316 C>T（Ser772Leu）。此外，本研究还鉴定了总共 7 个已知的 SNP。乳腺癌患者和对照组之间的基因型分布无显著差异。
在 RGSL1 中鉴定出的新突变为乳腺癌的病理生理学提供了新的见解。此外，HRM 分析是一种可靠且高度敏感的多外显子突变扫描方法。
