Role of protein kinase C alpha in the induction of carcinoembryonic antigen by transforming growth factor beta 1

J Cell Physiol. 1995 Jul;164(1):148-53. doi: 10.1002/jcp.1041640119.


Previous studies showed that transforming growth factor beta 1 (TGF beta 1) regulates the expression of carcinoembryonic antigen (CEA) and CEA-cross-reactive glycoproteins (CEA-GLYs) in human colon carcinoma cells through a signal-transducing pathway associated with protein kinase C (PKC) (Chakrabarty, J. Cell. Physiol., 1992, 152:494-499). In this study we determined the role of the PKC alpha isoform in the regulation of CEA and CEA-GLYs expression by TGF beta 1. Expression of PKC alpha antisense RNA, through transfection experiments with an antisense PKC alpha expression vector, resulted in down-modulation of PKC alpha RNA and protein expression. TGF beta 1 was unable to stimulate the expression and secretion of CEA in cells in which the expression of PKC alpha protein was substantially reduced. The ability of TGF beta 1 to stimulate the expression of the 95- and 55-kDa CEA-GLYs, however, was not affected. We therefore conclude that TGF beta 1 regulates the secretion and expression of CEA through a signal-transducing pathway associated with PKC alpha. TGF beta 1 may also regulate the expression of CEA-GLYs through signal-transducing pathways associated with other PKC isoforms.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Carcinoembryonic Antigen / metabolism*
  • Glycoproteins / metabolism
  • Humans
  • Isoenzymes / genetics
  • Isoenzymes / physiology*
  • Molecular Weight
  • Protein Kinase C / genetics
  • Protein Kinase C / physiology*
  • Protein Kinase C-alpha
  • RNA, Antisense / metabolism
  • RNA, Messenger / metabolism
  • Transforming Growth Factor beta / pharmacology*
  • Tumor Cells, Cultured


  • Carcinoembryonic Antigen
  • Glycoproteins
  • Isoenzymes
  • RNA, Antisense
  • RNA, Messenger
  • Transforming Growth Factor beta
  • PRKCA protein, human
  • Protein Kinase C
  • Protein Kinase C-alpha