High affinity binding of VIP to human lung cancer cell lines.
The binding of 125I-VIP to human lung cancer cell lines was investigated. Radiolabeled VIP bound to adenocarcinoma, squamous cell carcinoma, large cell carcinoma and small cell lung cancer (SCLC) cell lines. As SCLC cell line NCI-N592 bound radiolabeled VIP well, its binding was further characterized. 125I-VIP bound to membranes in a specific and time dependent manner. 125I-VIP bound with high (Kd = 0.8 nM) and moderate affinity (Kd = 66 nM) to two classes of sites. Pharmacology studies indicated that the order of peptide potency was VIP much greater than PHI greater than secretin greater than VIP10-28. Because VIP receptors are present on human lung cancer cells, VIP may function as a regulatory peptide in lung cancer.
Shaffer
M M
MM
Department of Biochemistry, George Washington University School of Medicine and Health Sciences, Washington, DC 20037.
Carney
D N
DN
Korman
L Y
LY
Lebovic
G S
GS
Moody
T W
TW
D018288:Carcinoma, Small Cell / Q000032:analysis*; D006801:Humans; D007457:Iodine Radioisotopes; D008175:Lung Neoplasms / Q000032:analysis*; D008970:Molecular Weight; D011964:Receptors, Gastrointestinal Hormone / Q000032:analysis*; D018005:Receptors, Vasoactive Intestinal Peptide; D014407:Tumor Cells, Cultured / Q000032:analysis; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism*
D007457:Iodine Radioisotopes; D011964:Receptors, Gastrointestinal Hormone; D018005:Receptors, Vasoactive Intestinal Peptide; D014660:Vasoactive Intestinal Peptide