unc-93的人类同源物定位于6号染色体q27——散发性上皮性卵巢癌中的特征与分析。

The human homologue of unc-93 maps to chromosome 6q27 - characterisation and analysis in sporadic epithelial ovarian cancer.

作者信息

Liu Ying, Dodds Phillippa, Emilion Gracy, Mungall Andrew J, Dunham Ian, Beck Stephan, Wells R Spencer, Charnock F Mark L, Ganesan Trivadi S

机构信息

Cancer Research UK Molecular Oncology Laboratories, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford, OX3 9DS, UK.

出版信息

BMC Genet. 2002 Oct 15;3:20. doi: 10.1186/1471-2156-3-20.

DOI:10.1186/1471-2156-3-20

PMID:12381271

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC134458/

Abstract

BACKGROUND

In sporadic ovarian cancer, we have previously reported allele loss at D6S193 (62%) on chromosome 6q27, which suggested the presence of a putative tumour suppressor gene. Based on our data and that from another group, the minimal region of allele loss was between D6S264 and D6S149 (7.4 cM). To identify the putative tumour suppressor gene, we established a physical map initially with YACs and subsequently with PACs/BACs from D6S264 to D6S149. To accelerate the identification of genes, we sequenced the entire contig of approximately 1.1 Mb. Seven genes were identified within the region of allele loss between D6S264 and D6S149.

RESULTS

The human homologue of unc-93 (UNC93A) in C. elegans was identified to be within the interval of allele loss centromeric to D6S149. This gene is 24.5 kb and comprises of 8 exons. There are two transcripts with the shorter one due to splicing out of exon 4. It is expressed in testis, small intestine, spleen, prostate, and ovary. In a panel of 8 ovarian cancer cell lines, UNC93A expression was detected by RT-PCR which identified the two transcripts in 2/8 cell lines. The entire coding sequence was examined for mutations in a panel of ovarian tumours and ovarian cancer cell lines. Mutations were identified in exons 1, 3, 4, 5, 6 and 8. Only 3 mutations were identified specifically in the tumour. These included a c.452G>A (W151X) mutation in exon 3, c.676C>T (R226X) in exon 5 and c.1225G>A(V409I) mutation in exon 8. However, the mutations in exon 3 and 5 were also present in 6% and 2% of the normal population respectively. The UNC93A cDNA was shown to express at the cell membrane and encodes for a protein of 60 kDa.

CONCLUSIONS

These results suggest that no evidence for UNC93A as a tumour suppressor gene in sporadic ovarian cancer has been identified and further research is required to evaluate its normal function and role in the pathogenesis of ovarian cancer.

摘要

背景

在散发性卵巢癌中，我们之前报道过6号染色体6q27上D6S193位点存在等位基因缺失（62%），这提示可能存在一个假定的肿瘤抑制基因。基于我们的数据以及另一研究组的数据，等位基因缺失的最小区域位于D6S264和D6S149之间（7.4厘摩）。为了鉴定这个假定的肿瘤抑制基因，我们首先构建了一个基于酵母人工染色体（YAC）的物理图谱，随后构建了从D6S264到D6S149的基于细菌人工染色体（BAC）/噬菌体P1人工染色体（PAC）的物理图谱。为了加速基因鉴定，我们对大约1.1兆碱基的完整重叠群进行了测序。在D6S264和D6S149之间的等位基因缺失区域内鉴定出了7个基因。

结果

秀丽隐杆线虫unc-93（UNC93A）的人类同源基因被鉴定位于D6S149着丝粒侧的等位基因缺失区间内。该基因长24.5千碱基，由8个外显子组成。有两种转录本，较短的一种是由于外显子4的剪接缺失。它在睾丸、小肠、脾脏、前列腺和卵巢中表达。在一组8个卵巢癌细胞系中，通过逆转录聚合酶链反应（RT-PCR）检测到UNC93A的表达，在2/8的细胞系中鉴定出了这两种转录本。对一组卵巢肿瘤和卵巢癌细胞系的整个编码序列进行了突变检测。在外显子1、3、4、5、6和8中鉴定出了突变。仅在肿瘤中特异性鉴定出3个突变。这些突变包括外显子3中的c.452G>A（W151X）突变、外显子5中的c.676C>T（R226X）突变和外显子8中的c.1225G>A（V409I）突变。然而，外显子3和5中的突变在正常人群中分别也有6%和2%的发生率。UNC93A cDNA显示在细胞膜上表达，编码一个60千道尔顿的蛋白质。