Insulin-induced Enhancement Of 5-fluorouracil Chemotherapeutic Response And Its Mechanism

Chemotherapy is one of the main ways to treat malignant tumor currently, but many chemotherapeutic drugs damage normal cells with side effects when they kill cancer cells. Chemotherapy can't be done smoothly and clinical efficacy is poor. So it is very important to find chemosensitizers which improve the sensitivity of chemotherapeutic drugs and reduce side effects.Insulin is one metabolism accelerant. It can improve the metabolic level of cell and tissue. In addition, it can promote the synthesis of RNA and DNA, stimulate the growth of normal and cancer cells and induce cancer cells into the cycle of multiplication. It is known that slowly growing cancers with a low-growth fraction are less sensitive to chemotherapy, whereas rapidly growing tumors with high-growth fractions are more sensitive to chemotherapy. One of the main reasons is that rapidly growing cancers have higher metabolism level than slowly growing cancers and cancer cells in higher metabolism status are more subject to be attacked by chemotherapy drugs.Insulin was used properly as accelerant to modulate tumor cells into the state of high metabolism and active multiplication, which makes cancer tissue more sensitive to chemotherapeutic drugs. This study has demonstrated insulin can enhance the chemotherapeutic effect of 5-FU on nude mice transplanted tumor animal model without increasing toxicity. The result was in agreement with the previous study in vitro. In addition, the enhancement mechanism of insulin on 5-FU was also explored further.