Pituitary adenylate cyclase activating peptide receptors regulate the growth of non-small cell lung cancer cells.
We have identified pituitary adenylate cyclase activating peptide (PACAP) receptors on small cell lung cancer cell line NCI-N417 in a previous study. In this study, the role of PACAP in the growth and signal transduction of non-small cell lung cancer cells was investigated. Northern blot analysis with a full-length human PACAP receptor cDNA probe revealed a major 7.5-kb hybridizing transcript when total RNA extracted from NCI-H838 cells was used. PACAP bound with high affinity (Kd = 1 nM) to a single class of sites (Bmax = 14,000/cell) when NCI-H838 cells were used. Specific 125I-labeled PACAP binding was inhibited with high affinity by PACAP-27 and PACAP-38, with moderate affinity by PACAP(6-38), and with low affinity by vasoactive intestinal polypeptide, PACAP(28-38), and PACAP(16-38). PACAP-27 elevated cAMP in a dose-dependent manner, and the increase in cAMP caused by PACAP was reversed by PACAP(6-38). PACAP-27, but not vasoactive intestinal polypeptide, elevated cytosolic Ca2+ in individual NCI-H838 cells. PACAP-27 stimulated arachidonic acid release, and the increase caused by PACAP was reversed by PACAP(6-38). PACAP-27 stimulated colony formation in NCI-H838 cells, whereas the PACAP antagonist PACAP(6-38) reduced colony formation in the absence or presence of exogenous PACAP-27. In nude mice bearing NCI-H838 xenografts, PACAP(6-38) slowed tumor growth significantly. These data suggest that biologically active type 1 PACAP receptors are present on human non-small cell lung cancer cells, which exhibit dual signal transduction pathways and regulate cell proliferation.
Zia
F
F
Department of Microbiology, George Washington University Medical Center, Washington, District of Columbia 20037, USA.
Fagarasan
M
M
Bitar
K
K
Coy
D H
DH
Pisegna
J R
JR
Wank
S A
SA
Moody
T W
TW
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D016718:Arachidonic Acid / Q000378:metabolism; D001665:Binding Sites; D015152:Blotting, Northern; D002118:Calcium / Q000378:metabolism; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D002455:Cell Division / Q000502:physiology; D000242:Cyclic AMP / Q000378:metabolism; D005260:Female; D006801:Humans; D007424:Intracellular Fluid / Q000378:metabolism; D007457:Iodine Radioisotopes; D008175:Lung Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D009479:Neuropeptides / Q000378:metabolism / Q000494:pharmacology; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide; D051237:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I; D011979:Receptors, Pituitary Hormone / Q000378:metabolism / Q000502:physiology*; D012680:Sensitivity and Specificity; D014183:Transplantation, Heterologous; D014407:Tumor Cells, Cultured
C495401:ADCYAP1 protein, human; C495402:Adcyap1 protein, mouse; D000970:Antineoplastic Agents; D007457:Iodine Radioisotopes; D009479:Neuropeptides; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide; D051237:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I; D011979:Receptors, Pituitary Hormone; D016718:Arachidonic Acid; D000242:Cyclic AMP; D002118:Calcium