Medical Genetics Department, National Institute of Genetic Engineering and Biotechnology, Pajoohesh Blvd., Km. 17 Tehran-Karaj Highway, Tehran, Iran.
Arch Iran Med. 2010 Mar;13(2):111-5.
Golestan Province in north-eastern Iran has one of the highest incidence rates for esophageal squamous cell carcinoma (ESCC) worldwide. Earlier studies have reported higher incidence rates in the areas of Golestan which are mainly inhabited by individuals of the Turkmen ethnic group. However, it is not clear whether in those areas the incidence among Turkmens is higher in comparison to non-Turkmens. Some previous studies have suggested that environmental factors might play a more essential role in ESCC carcinogenesis in Golestan than a genetic background. If environmental factors instead of a genetic background are the major risk factors, therefore the prevalence of known environmental risk factors would not significantly differ among ESCC cases of different ethnic groups. To investigate the role of environmental factors versus genetic background by using the above concept, we have compared the prevalence of known risk factors for ESCC among Turkmen and non-Turkmen ESCC cases.
Study participants were histopathologically proven ESCC cases from Golestan Province. They were recruited in the study from December 2003 to June 2007. The prevalence of the most important known risk factors for ESCC in Turkmen and non-Turkmen ESCC cases was compared using Chi-squared and Fisher's exact tests.
Of 300 ESCC cases recruited in the study, 171 (57.0%) and 129 (43.0%) cases were Turkmen and non-Turkmen, respectively. In the majority of the investigated risk factors which included tobacco, nass, and opium use, hot and extremely hot tea consumption, as well as decreased levels of education; there was no significant difference between Turkmen and non-Turkmen ESCC cases in the prevalence of exposure.
Our findings support the suggestion that a substantial difference between Turkmens and non-Turkmens in terms of genetic susceptibility to ESCC is unlikely. Nevertheless, the moderate effect of genetic factors cannot be ruled out. Further studies to investigate potential environmental and genetic risk factors of ESCC in Golestan and the interaction between environmental and genetic factors are warranted.
伊朗东北部的戈勒斯坦省是世界上食管癌鳞状细胞癌（ESCC）发病率最高的地区之一。早期的研究报告称，戈勒斯坦主要居住着土库曼族群体的地区发病率更高。然而，目前尚不清楚在这些地区，土库曼族人群的发病率是否高于非土库曼族人群。一些先前的研究表明，环境因素在戈勒斯坦的 ESCC 癌变中可能发挥比遗传背景更重要的作用。如果环境因素而不是遗传背景是主要的危险因素，那么不同族裔的 ESCC 病例中，已知环境危险因素的流行情况不会有显著差异。为了利用上述概念来研究环境因素与遗传背景的作用，我们比较了土库曼族和非土库曼族 ESCC 病例中已知 ESCC 危险因素的流行情况。
本研究的参与者为经组织病理学证实的戈勒斯坦省 ESCC 病例。他们是 2003 年 12 月至 2007 年 6 月期间招募入组的。使用卡方检验和 Fisher 确切检验比较了土库曼族和非土库曼族 ESCC 病例中最重要的已知 ESCC 危险因素的流行情况。
在入组的 300 例 ESCC 病例中，171 例（57.0%）和 129 例（43.0%）为土库曼族和非土库曼族，在包括烟草、纳塞、鸦片使用、热饮和极热饮以及受教育程度降低在内的大多数调查危险因素中，土库曼族和非土库曼族 ESCC 病例的暴露率没有显著差异。
我们的研究结果支持这样一种观点，即土库曼族和非土库曼族在 ESCC 遗传易感性方面存在显著差异的可能性不大。然而，遗传因素的中度作用不能被排除。进一步的研究需要调查戈勒斯坦 ESCC 的潜在环境和遗传危险因素以及环境和遗传因素之间的相互作用。
