Effects of smokeless tobacco on chemically transformed hamster oral keratinocytes: role of angiotensin I-converting enzyme.
The purpose of this study was to determine whether exposure of chemically transformed golden Syrian hamster oral epidermoid carcinoma cell (HCPC-1) cultures to smokeless tobacco extract (STE) is associated with a decrease in specific angiotensin I-converting enzyme (ACE) activity and whether this decrease potentiates bradykinin-induced cell growth. We found that STE induced a significant concentration- and time-dependent decrease in ACE activity in cultured HCPC-1 cells (P < 0.05). STE alone had no significant effect on cell number. Bradykinin alone induced a slight, but significant, increase in cell number (P < 0.05). These effects were significantly potentiated by STE (P < 0.01). We conclude that STE potentiates bradykinin-induced HCPC-1 cell growth, in part by attenuating specific ACE activity in these cells.
Department of Internal Medicine, University of Nebraska Medical Center, Omaha.
G
G
Müns
J K
JK
Vishwanatha
I
I
Rubinstein
D000818:Animals; D001920:Bradykinin / Q000494:pharmacology; D002294:Carcinoma, Squamous Cell / Q000139:chemically induced / Q000201:enzymology*; D002455:Cell Division / Q000187:drug effects; D006224:Cricetinae; D015603:Keratinocytes / Q000187:drug effects / Q000473:pathology; D008647:Mesocricetus; D009062:Mouth Neoplasms / Q000139:chemically induced / Q000201:enzymology*; D007703:Peptidyl-Dipeptidase A / Q000502:physiology*; D010947:Plants, Toxic; D014030:Tobacco, Smokeless / Q000009:adverse effects*; D014407:Tumor Cells, Cultured
D007703:Peptidyl-Dipeptidase A; D001920:Bradykinin