Autocrine motility-stimulatory pathways of oral premalignant lesion cells.
Patients with premalignant oral lesions have varying levels of risk of developing oral squamous cell carcinoma (OSCC), whose aggressiveness requires increased motility. Not known is if and how premalignant oral lesion cells acquire the increased motility characteristic of OSCC. This was addressed by immunohistochemical analysis of banked premalignant lesion tissues and by functional analyses using cultures established from premalignant oral lesions and OSCC. These studies showed premalignant oral lesion cells and OSCC to be more motile than normal keratinocytes. Concomitantly, levels of ceramide were reduced. The activity of the protein phosphatase PP-2A, which restricts motility and which can be activated by ceramide, was also diminished. This was due to IL-10 released from premalignant lesion cells. Treatment with a membrane-permeable ceramide restored PP-2A activity and blocked migration. These studies show an autocrine motility-stimulatory pathway that is mediated in premalignant lesion cells by IL-10 through its reduction of ceramide levels and inhibition of PP-2A activity.
Young
M Rita I
MR
Research Service 151, Ralph H. Johnson VA Medical Center, Ralph H. Johnson Veterans Affairs Hospital, Charleston, SC 29401-5799, USA. rita.young@va.gov
Neville
Brad W
BW
Chi
Angela C
AC
Lathers
Deanne M R
DM
Gillespie
M Boyd
MB
Day
Terry A
TA
D015153:Blotting, Western; D002294:Carcinoma, Squamous Cell / Q000201:enzymology / Q000378:metabolism / Q000473:pathology*; D002465:Cell Movement; D002518:Ceramides / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D016753:Interleukin-10 / Q000494:pharmacology; D009062:Mouth Neoplasms / Q000201:enzymology / Q000378:metabolism / Q000473:pathology*; D010749:Phosphoprotein Phosphatases / Q000378:metabolism; D011230:Precancerous Conditions / Q000201:enzymology / Q000378:metabolism / Q000473:pathology*
D002518:Ceramides; D016753:Interleukin-10; D010749:Phosphoprotein Phosphatases