IGF-1 and IGF-1BP3 in gastric adenocarcinoma. Preliminary study

Insulin-like growth factor-1 (IGF-1) is a mitogenic and anti-apoptotic factor, mainly produced by the liver, which regulates cell proliferation. Most serum IGF-1s are bound with IGF-1BP3. Plasma IGF-1 values are positively related to cancer risk (breast, colon, and lung cancer) and seem to have a prognostic significance in prostatic cancer. The aim of this study is to investigate the relationship between IGF-1, IGF-1BP3 and gastric cancer.

IGF-1 and IGF-1BP3 serum levels were measured in 26 consecutive patients (M/F = 15/11, mean age 65 yrs) with histologically proven gastric adenocarcinoma from January 1999 to December 2000. Blood samples were collected at baseline, before surgery with radical intent (total and subtotal gastrectomies + D2 lymphadenectomy), and then at 14th and 50th postoperative days. These values were compared to a control group of healthy people.

At baseline was observed a significant increase of IGF-1 serum levels in cancer patients versus control group (p < 0.001). All gastric cancer patients showed IGF-1 over normal limits. After surgery there was a significant decrease of IGF-1 levels (14th day vs. baseline, p = 0.001) that was still present in late postoperative period (50th day). At baseline IGF-1 values were not related to tumor extension or nodal involvement status. Otherwise in postoperative period IGF-1 significantly decreased in earlier stages (N0; T < or = 2) but not in more advanced ones (N+; T > 2). At baseline, IGF-1BP3 values were increased compared to control group but did not significantly decrease after surgery.

IGF-1 values in gastric cancer patients are increased compared to control group, without stratification for stage and nodal status. Moreover radical surgery, with complete tumor ablation, induces a significant decrease in IGF-1 levels, without reach normal limits. Besides at baseline abnormally higher IGF-1BP3 values were observed, suggesting an alteration in IGF-1 and IGF-1BP3 system.