Overexpression of wild-type PKD2 leads to increased proliferation and invasion of BON endocrine cells.
Carcinoid tumors are rare neuroendocrine tumors with a predilection for the gastrointestinal tract. Protein kinase D (PKD), a novel serine/threonine protein kinase, has been implicated in the regulation of transport processes in certain cell types. We have reported an important role for PKD in stimulated peptide secretion from a human (BON) carcinoid cell line; however, the role of PKD isoforms, including PKD2, in the proliferation and invasion of carcinoid tumors remains unclear. In the present study, we found that overexpression of PKD2 by stable transfection of BON cells with PKD2-wild type (PKD2WT) significantly increased proliferation and invasion compared to cells transfected with PKD2-kinase dead (PKD2KD) or pcDNA3 (control). Similarly, inhibition of PKD2 activity with small interfering RNA (siRNA) significantly decreased proliferation and invasion compared to cells transfected with non-targeting control (NTC) siRNA. These data support an important role for PKD2 in carcinoid tumor progression. Targeted inhibition of the PKD family may prove to be a novel treatment option for patients with carcinoid tumors.
Jackson
Lindsey N
LN
Department of Surgery, The University of Texas Medical Branch, Galveston, TX, USA.
Li
Jing
J
Chen
L Andy
LA
Townsend
Courtney M
CM
Evers
B Mark
BM
D002276:Carcinoid Tumor / Q000201:enzymology* / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D018450:Disease Progression; D006801:Humans; D009361:Neoplasm Invasiveness; D010190:Pancreatic Neoplasms / Q000201:enzymology / Q000473:pathology; D000091283:Protein Kinase D2; D011494:Protein Kinases / Q000096:biosynthesis* / Q000235:genetics* / Q000502:physiology; D014162:Transfection
D000091283:Protein Kinase D2; D011494:Protein Kinases