Inhibition of tumor cell kinetics and serum insulin growth factor I levels by octreotide in colorectal cancer patients.
OBJECTIVE
Octreotide was shown to inhibit the growth of colon cancer and to reduce serum concentrations of tumor growth factors such as insulin-like growth factor I (IGF-I) and epidermal growth factor (EGF) in vitro and in animal models. Effects of octreotide on tumor cell kinetics and serum concentration of IGF-I and EGF in patients with colorectal cancer were evaluated.


METHODS
Seventy-five patients with colorectal cancer were randomized to receive octreotide (200 micrograms daily) in the 2 weeks before surgery or the usual medications. Samples of tumor tissue were taken at endoscopy and at surgery. [3H]Thymidine labeling index and flow cytometry were used to assess the S-phase fraction. In octreotide-treated patients, plasma levels of IGF-I, EGF, and growth hormone were assessed before and after treatment.


RESULTS
There was a statistically significant reduction in the mean percentage of the S-phase fraction as a result of octreotide treatment measured by both [3H]thymidine labeling index (P = 0.001) and flow cytometry (P = 0.001). No reduction in the percentage of the S-phase fraction was observed in the control group patients. Serum values of IGF-I were significantly reduced by octreotide, whereas EGF and growth hormone levels were not affected.


CONCLUSIONS
Octreotide reduces the proliferative activity of tumor cells and the serum IGF-I levels in patients with colorectal cancer. This activity may have a role in the treatment of colorectal cancer.
Cascinu
S
S
Section of Experimental Oncology, Azienda Ospedeliera S. Salvatore, Pesaro, Italy.
Del Ferro
E
E
Grianti
C
C
Ligi
M
M
Ghiselli
R
R
Foglietti
G
G
Saba
V
V
Lungarotti
F
F
Catalano
G
G
D000328:Adult; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D002453:Cell Cycle; D015179:Colorectal Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000473:pathology*; D004815:Epidermal Growth Factor / Q000097:blood; D005434:Flow Cytometry; D019382:Human Growth Hormone / Q000097:blood; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008875:Middle Aged; D015282:Octreotide / Q000627:therapeutic use*; D011300:Preoperative Care; D016196:S Phase; D013936:Thymidine / Q000378:metabolism
D018931:Antineoplastic Agents, Hormonal; D019382:Human Growth Hormone; D004815:Epidermal Growth Factor; D007334:Insulin-Like Growth Factor I; D015282:Octreotide; D013936:Thymidine