Vega A, Barros F, Lleonart M E, Ramon y Cajal S, Carracedo A
Unit of Molecular Medicine, Hospital Provincial de Conxo, Santiago de Compostela, Spain.
Anticancer Res. 2001 Jul-Aug;21(4A):2855-60.
To further evaluate sporadic colon carcinoma risk associated with rare HRAS1 VNTR alleles, the relationship with microsatellite instability and with HRAS1 VNTR instability.
The HRAS1 VNTR was genotyped in 121 tumors and normal samples from sporadic colon carcinoma patients (47 right and 74 left colon) and in 109 samples from healthy individuals. The HRAS1 alleles were identified using PCR and automatic fluorescent electrophoresis detection combined with MVR-PCR (Minisatellite Variant Repeat-Polymerase Chain Reaction). Microsatellite Instability (MI) was analysed with 10 microsatellite markers.
A relative risk of 3.04 (95% CI: 1.16-4.92) associated with rare alleles was obtained. No HRAS1 minisatellite instability was present in the tumors. Samples with MI were equally distributed between the common and rare HRAS1 allele groups, while the distribution of HRAS1 alleles in samples with MI was similar in right and left colorectal carcinoma.
Rare HRAS1 VNTR alleles are associated with colorectal carcinoma risk independent of the tumor location. MI is not likely to be involved in the same underlying defect that generates rare HRAS1 alleles in colorectal carcinoma.
为进一步评估与罕见HRAS1可变数目串联重复序列（VNTR）等位基因相关的散发性结肠癌风险、与微卫星不稳定性以及与HRAS1 VNTR不稳定性的关系。
对121例散发性结肠癌患者（47例右半结肠和74例左半结肠）的肿瘤及正常样本，以及109例健康个体的样本进行HRAS1 VNTR基因分型。采用聚合酶链反应（PCR）及自动荧光电泳检测结合小卫星变异重复-聚合酶链反应（MVR-PCR）来鉴定HRAS1等位基因。使用10个微卫星标记分析微卫星不稳定性（MI）。
获得了与罕见等位基因相关的相对风险为3.04（95%可信区间：1.16 - 4.92）。肿瘤中未出现HRAS1小卫星不稳定性。MI样本在常见和罕见HRAS1等位基因组中分布均匀，而在右半结肠癌和左半结肠癌中，MI样本中HRAS1等位基因的分布相似。
罕见的HRAS1 VNTR等位基因与结肠癌风险相关，且与肿瘤位置无关。MI不太可能参与在结肠癌中产生罕见HRAS1等位基因的同一潜在缺陷。
