Calcitonin increases tumorigenicity of prostate cancer cells: evidence for the role of protein kinase A and urokinase-type plasminogen receptor.

Abstract

The expression of human (h) calcitonin (CT) and its receptor (CTR) is localized to basal epithelium in benign prostates but is distributed in whole epithelium of malignant prostates. Moreover, the abundance of hCT and CTR mRNA in primary prostate tumors positively correlates with the tumor grade. We tested the hypothesis that the modulation of endogenous hCT expression of prostate cancer (PC) cell lines alters their oncogenicity. The effect of modulation of hCT expression on oncogenic characteristics was examined in LNCaP and PC-3M cell lines. The endogenous hCT expression was modulated using either constitutively active expression vector containing hCT cDNA or anti-hCT hammerhead ribozymes. The changes in the oncogenicity of cell sublines was assessed with cell proliferation assays, invasion assays, colony formation assays, and in vivo growth in athymic nude mice. Up-regulation of hCT in PC-3M cells and or enforced hCT expression in LNCaP cells dramatically enhanced their oncogenic characteristics. In contrast, the down-regulation of hCT in PC-3M cells led to a dramatic decline in their oncogenicity. These results, when combined with our other results, that the expression of hCT in primary PCs increase with tumor grade, suggest an important role for hCT in the progression of PC to a metastatic phenotype.

• Authors: Shibu Thomas, Srinivasulu Chigurupati, Muralidharan Anbalagan, Girish Shah
• Journal: Molecular endocrinology (Baltimore, Md.) (Mol Endocrinol) Vol. 20 Issue 8 Pg. 1894-911 (Aug 2006) ISSN: 0888-8809 [Print] United States
• PMID: 16574742 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)

Chemical References

• PLAUR protein, human
• Plaur protein, mouse
• RNA, Messenger
• Receptors, Cell Surface
• Receptors, Urokinase Plasminogen Activator
• Calcitonin
• Cyclic AMP-Dependent Protein Kinases
• Urokinase-Type Plasminogen Activator

Topics

• Animals
• Calcitonin (metabolism, pharmacology)
• Cell Proliferation
• Cyclic AMP-Dependent Protein Kinases (physiology)
• Disease Progression
• Gene Expression
• Gene Silencing
• Humans
• Male
• Mice
• Mice, Nude
• Neoplasm Invasiveness
• Neoplastic Stem Cells
• Prostatic Neoplasms (metabolism, pathology)
• RNA, Messenger (metabolism)
• Receptors, Cell Surface (physiology)
• Receptors, Urokinase Plasminogen Activator
• Transfection
• Tumor Cells, Cultured
• Urokinase-Type Plasminogen Activator (physiology)
• Xenograft Model Antitumor Assays