Apoptosis-induction and phosphorylation state in human pancreatic carcinoma xenografts following octreotide treatment.

Abstract

BACKGROUND:

Some exocrine pancreatic carcinomas are responsive to hormonal manipulations, but the mechanism is not fully understood.

MATERIALS AND METHODS:

Human pancreatic cancer xenografts (PZX-15/F4) grown in immunosuppressed mice were treated with Sandostatin (2 x 100 micrograms/b.w. s.c.) for 4 weeks. Mitotic and apoptotic activities were assessed and supplemented with immunohistochemical detection of phosphotyrosine and bcl-2 protein.

RESULTS:

In the treated group 5/16 tumors exhibited a 20-68% volume reduction, and the number of apoptotic cells was significantly increased (18.1 +/- 3.1/mm2 vs. 6.2 +/- 1.1/mm2 in controls, P < 0.0012). At the same time, a highly significant reduction in the number of the phosphotyrosine-positive tumor cells was observed (40.9% from 64.9%; P < 0.0001). The mitotic activity did not change significantly. Both the untreated and the treated tumors proved to be bcl-2 negative.

CONCLUSIONS:

The results indicated that the octreotide triggered an apoptosis-induction in a human pancreatic cancer xenograft, coupled with the increased dephosphorylation state in the tumors, but the mitotic activity was not affected and bcl-2 expression has not been induced.

• Authors: A Zalatnai, V Pogány
• Journal: Anticancer research (Anticancer Res) 2001 Jan-Feb Vol. 21 Issue 1A Pg. 477-80 ISSN: 0250-7005 [Print] Greece
• PMID: 11299782 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents, Hormonal
• Phosphotyrosine
• Octreotide

Topics

• Animals
• Antineoplastic Agents, Hormonal (pharmacology, therapeutic use)
• Apoptosis (drug effects)
• Carcinoma (drug therapy, metabolism, pathology)
• Humans
• Mice
• Mitotic Index
• Octreotide (pharmacology, therapeutic use)
• Pancreatic Neoplasms (drug therapy, metabolism, pathology)
• Phosphorylation (drug effects)
• Phosphotyrosine (metabolism)
• Xenograft Model Antitumor Assays