Effective local control of prostate cancer by intratumoral injection of (166)Ho-chitosan complex (DW-166HC) in rats.
OBJECTIVE
The aim of this study was to evaluate the therapeutic effect and morphological alterations resulting from (166)Ho-chitosan complex (DW-166HC) in an animal model of prostate cancer.


METHODS
First, in a subcutaneous tumor model, 80 rats were randomly divided into four groups (n=20 in each group), and intratumoral injections of 0.05 ml (normal saline in group 1,( 165)Ho-chitosan complex solution in group 2, DW-166HC solution (10 mCi) in group 3, and DW-166HC solution (20 mCi) in group 4) were performed when the tumor measured approximately 1 cm along its long axis in each group. Further, in an orthotopic tumor model, 40 rats were similarly randomly divided into four groups (n=10 in each group), and intraprostatic injections of 0.05 ml [PBS in group 1,( 165)Ho-chitosan complex solution in group 2, DW-166HC solution (0.5 mCi) in group 3 and DW-166HC solution (1 mCi) in group 4] were performed at 1 week after implantation of the AIT cell line in the ventral prostate.


RESULTS
In the subcutaneous tumor model, mean tumor weights of groups 3 and 4 were significantly lower than those of groups 1 and 2 at 2 and 4 weeks post injection (p<0.05). At 2 and 4 weeks after injection in the orthotopic tumor model, the mean weights of the prostate, including tumor, in groups 3 and 4 were also significantly lower than those in groups 1 and 2 (p<0.05). No adverse injury was seen in adjacent organs at histopathologic examination.


CONCLUSIONS
Intratumoral injection of the beta-emitting radionuclide (166)Ho as a form of complex solution with chitosan appears to be a promising alternative therapeutic modality for the local control of prostate cancer.
Kwak
Cheol
C
Department of Urology, Seoul National University College of Medicine and Clinical Research Institute, Seoul National University Hospital, Seoul, Korea.
Hong
Sung Kyu
SK
Seong
Seung Kyoo
SK
Ryu
Jei Man
JM
Park
Moon Soo
MS
Lee
Sang Eun
SE
D000818:Animals; D001835:Body Weight / Q000528:radiation effects; D002686:Chitin / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D006695:Holmium / Q000008:administration & dosage* / Q000009:adverse effects; D015552:Injections, Intralesional / Q000379:methods*; D008297:Male; D009942:Organometallic Compounds / Q000008:administration & dosage* / Q000009:adverse effects; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000532:radiotherapy*; D011868:Radioisotopes / Q000008:administration & dosage* / Q000009:adverse effects; D019275:Radiopharmaceuticals / Q000008:administration & dosage / Q000009:adverse effects; D051381:Rats; D015996:Survival Rate; D016896:Treatment Outcome
C116411:DW 166HC; D009942:Organometallic Compounds; D011868:Radioisotopes; D019275:Radiopharmaceuticals; D002686:Chitin; D006695:Holmium