Establishment of radioimmunotherapy for advanced rectal cancer; Induction of efficient abscopal effect

2014 Fiscal Year Final Research Report

• Project/Area Number: 24390309
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Digestive surgery
• Research Institution: The University of Tokyo
• Principal Investigator: KITAYAMA Joji 東京大学, 医学部附属病院, 准教授 (20251308)
• Co-Investigator(Kenkyū-buntansha): SUNAMI Eiji 東京大学, 医学部附属病院, 講師 (70345205)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: abscopal effect / 免疫放射線療法

Outline of Final Research Achievements

The addition of lentinan, anti-tumor polysaccharide isolated from the fruit body of shiitake, on radiation to subcutaneous tumor of LuM-1 increased the number of Gr-1(+)CD11b(+) MDSC in splenocytes, although it could not induce the augment of antitumor effects of irradiated tumor as well as non-irradiated lung metastasis. Transfection of PS-PLA1 to LuM-1 can induce PS expression of irradiated cells. The effect of PS-PLA1 on radiosensitivity is under investigation. On the other hand, in patients with rectal cancer who received neoadjuvant chemoradiotherapy (CRT), the response is significantly associated with preoperative number of CD4(+) helper T lymphocytes, as well as platelet number, soluble CD40-ligand (sCD40L). Altogether, our data suggest that the tumor response of rectal cancer against RT is at least partly dependent on host immune response. Combination of immunotherapy to conventional (chemo)radiotherapy is a new approach for the improvement of the treatment of rectal cancer.

Free Research Field

腫瘍外科学