title: Long-term effect on EMT6 tumors in mice induced by combination of laser immunotherapy and surgery.
abstract: Laser immunotherapy (LI) has been demonstrated to be a promising modality for cancer treatment. The present study was designed to further investigate the impact of LI combined with surgery. LI consists of a near-infrared laser, a light-absorbing dye (indocyanine green, ICG), and an immunostimulant (glycated chitosan, GC). ICG and GC were intratumorally injected, followed by laser irradiation. Female BALB/c mice bearing EMT6 tumor cells were divided into 4 groups: control, LI, LI followed by immediate surgery resection of residual tumor (LI + S(0wk)), and LI followed by surgical removal of residual tumor after 1 week (LI + S(1wk)). Successfully treated mice from all treatment groups were rechallenged twice with 10(5) and 5 × 10(5) EMT6 cells, respectively. The LI + S(1wk) group had the highest survival rate (72%) after 90 days, whereas the mice survival rates of the LI + S(0wk), LI, and control groups were 50%, 46%, 0%, respectively. The median survival times of control, LI, LI + S(0wk), and LI + S(1wk) groups were 32, 66, 74, and 90 days, respectively. Survival rates of the treated mice after the first and second tumor rechallenges, ranging from 73% to 95%, were not significantly different among the 4 groups (P > .05). The results show that LI is a useful tool for the treatment of tumor-bearing mice. Long-term antitumor effect can be induced by LI. They also indicate that combination of LI with surgery can further improve the therapeutic efficiency of LI.
authors.affiliation: Chinese PLA General Hospital, Beijing, China.
authors.forename: Xiaosong
authors.initials: X
authors.lastname: Li
authors.forename: Henry
authors.initials: H
authors.lastname: Le
authors.forename: Roman F
authors.initials: RF
authors.lastname: Wolf
authors.forename: Vivian A
authors.initials: VA
authors.lastname: Chen
authors.forename: Akhee
authors.initials: A
authors.lastname: Sarkar
authors.forename: Robert E
authors.initials: RE
authors.lastname: Nordquist
authors.forename: Halie
authors.initials: H
authors.lastname: Ferguson
authors.forename: Hong
authors.initials: H
authors.lastname: Liu
authors.forename: Wei R
authors.initials: WR
authors.lastname: Chen
mesh_terms: D056704:Adaptive Immunity; D000818:Animals; D048271:Chitosan / Q000627:therapeutic use; D005260:Female; D007167:Immunotherapy; D007208:Indocyanine Green / Q000627:therapeutic use; D053208:Kaplan-Meier Estimate; D054023:Lasers, Semiconductor / Q000627:therapeutic use*; D008325:Mammary Neoplasms, Experimental / Q000276:immunology / Q000601:surgery / Q000628:therapy*; D051379:Mice; D008807:Mice, Inbred BALB C; D012509:Sarcoma / Q000628:therapy*; D013997:Time Factors
chemical_list: C121252:glycated chitosan; D048271:Chitosan; D007208:Indocyanine Green