Adiponectin Is Inversely Associated With Tumour Grade in Colorectal Cancer Patients

Colorectal cancer is frequently associated with metabolic diseases. Adiponectin (APN) is an insulin-sensitizing adipokine circulating as low molecular weight (LMW), medium molecular weight (MMW) and high molecular weight (HMW) oligomers; the latter are the most bio-active oligomers. APN, through AdipoR1, AdipoR2 and T-cadherin receptors, regulates inflammation, and proliferation. Considering the anti-proliferative and anti-inflammatory properties of APN, we investigated the involvement of the "APN system" in colorectal cancer.A total of 44 colorectal cancer patients and 51 healthy controls were recruited. We analysed APN and HMW oligomers in sera, AdipoR1, AdipoR2 and T-cadherin expression in non-cancerous and cancerous colon tissues.we found statistically lower levels of APN in patients compared to controls, with a specific decrease of HMW oligomers. Importantly, APN correlated to cancer grade. AdipoR1 was found overexpressed in cancerous compared to non-cancerous tissues while AdipoR2 and T-cadherin were down-regulated.The deregulated expression of the "APN system" in colorectal cancer with a specific correlation to tumor grade suggests APN as a promising biomarker in colorectal cancer.