Abstract:
Obesity is associated with an increased risk for 13 different cancers. The increased risk for cancer in obesity is mediated by obesity-associated changes in the immune system. Obesity has distinct effects on different types of inflammation that are tied to tumorigenesis. For example, obesity promotes chronic inflammation in adipose tissue that is tumor-promoting in peripheral tissues. Conversely, obesity inhibits acute inflammation that rejects tumors. Obesity therefore promotes cancer by differentially regulating chronic versus acute inflammation. Given that obesity is chronic, the initial inflammation in adipose tissue will lead to systemic inflammation that could induce compensatory anti-inflammatory reactions in peripheral tissues to suppress chronic inflammation. The overall effect of obesity in peripheral tissues is therefore dependent on the duration and severity of obesity. Adipose tissue is a complex tissue that is composed of many cell types in addition to adipocytes. Further, adipose tissue cellularity is different at different anatomical sites throughout the body. Consequently, the sensitivity of adipose tissue to obesity is dependent on the anatomical location of the adipose depot. For example, obesity induces more inflammation in visceral than subcutaneous adipose tissue. Based on these studies, the mechanisms by which obesity promotes tumorigenesis are multifactorial and immune cell type-specific. The objective of our paper is to discuss the cellular mechanisms by which obesity promotes tumorigenesis by regulating distinct types of inflammation in adipose tissue and the tumor microenvironment.
摘要:
肥胖与13种不同癌症的风险增加有关。肥胖中患癌症的风险增加是由肥胖相关的免疫系统变化介导的。肥胖对与肿瘤发生有关的不同类型的炎症有不同的影响。例如,肥胖会促进脂肪组织中的慢性炎症,从而促进外周组织中的肿瘤。相反,肥胖抑制排斥肿瘤的急性炎症。因此,肥胖通过差异调节慢性与急性炎症而促进癌症。鉴于肥胖是慢性的,脂肪组织的初始炎症会导致全身性炎症,可在外周组织中诱导代偿性抗炎反应以抑制慢性炎症。因此,肥胖在外周组织中的总体作用取决于肥胖的持续时间和严重程度。脂肪组织是由除脂肪细胞之外的许多细胞类型组成的复杂组织。Further,在整个身体的不同解剖部位,脂肪组织的细胞组成是不同的。因此,脂肪组织对肥胖的敏感性取决于脂肪库的解剖位置。例如,肥胖引起的内脏炎症比皮下脂肪组织多。基于这些研究,肥胖促进肿瘤发生的机制是多因素和免疫细胞类型特异性的.本文的目的是讨论肥胖通过调节脂肪组织和肿瘤微环境中不同类型的炎症来促进肿瘤发生的细胞机制。