Obesity and Carcinogenesis

肥胖影響癌症形成之可能機轉

謝博軒(Po-Shiuan Hsieh)

《台灣癌症醫學雜誌》 27卷6期 (2011/12) Pp. 242-256

https://doi.org/10.6323/JoCRP.2011.27.6.2

摘要

肥胖盛行率越來越高是全球趨勢，而且不只和心血管疾病及糖尿病的發生有密切的關聯性，目前也發現其與某些癌症的發生也有顯著的相關性，從病因學的角度來分析肥胖相關癌症形成的機轉，目前的研究主要有兩大主要的方向：第一聚焦在肥胖造成的脂肪組織功能異常包括脂肪細胞肥大和脂肪組織發炎，會造成脂肪分泌激素的增加如Leptin, PAI-1或減少如Adiponectin，以及發炎性細胞激素如TNF-alpha和IL-6分泌的大量增加，後續造成胰島素抗性和系統性發炎的現象都與促進癌症的形成有密切的關聯性，另一方面，脂溶性的環境治癌物不易分解會長期累積在脂肪組織中，有些成分如Benzopyrene存在香菸及家庭油煙中和OTCs塑膠製品的熱穩定劑和殺菌劑等成分會抑制脂肪分解作用，造成肥胖，又會經由釋放脂肪組織中囤積的致癌物，加成肥胖所可能造成的致癌作用。

關鍵字

肥胖 ； 脂肪組織功能異常 ； 脂溶性環境致癌物 ； 癌症形成機轉

並列摘要

Obesity is reaching epidemic levels worldwide, a troubling phenomenon that increases the risk of cardiovascular diseases and type 2 diabetes. Recently, it has been suggested that obesity has a pathological link with cancer. Obesity is strongly associated with changes in the physiological function of adipose tissue, leading to insulin resistance, chronic inflammation, and altered secretion of adipokines. Several of these factors are directly involved in carcinogenesis and cancer progression, such as insulin resistance, increased levels of leptin, plasminogen activator inhibitor-1, endogenous sex steroids, decreased levels of adiponectin, and chronic inflammation. Additionally, adipose tissue has also been hypothesized to act as a reservoir for lipophilic, liposoluble environmental carcinogens, so that chemical pollution may indirectly promote both overweight/obesity and cancer. Moreover, it has also been suggested that many carcinogens stored in the adipose tissue could be released in periodic doses in the circulatory system and therefore target peripheral tissues to induce carcinogenesis. Such carcinogens mainly include organochlorine pesticides and polychlorinated biphenyls (PCBs). Their association with an increased risk of cancer appears to have been demonstrated for breast and prostate carcinoma, as well as for lymphoma. In this study, we reviewed the relevant evidence focusing on adipose tissue dysfunction as a unifying causal factor for cancer, as well as the hypothesis of chemical pollutants and their link to obesity and carcinogenesis.

並列關鍵字

obesity ； dysfunctional adipose tissue ； liposoluble environmental carcinogens ； carcinogenesis