Article Text

PDF
190 TAPASIN AND HLA CLASS I DOWN-REGULATED IN PRIMARY HUMAN MULTIPLE MYELOMA: SUITABLE INDICATOR OF POOR PROGNOSIS.
  1. B. Vélez1,
  2. F. Grizzi3,
  3. W. Wenhan1,
  4. J. Pinkston1,
  5. N. D. Cunha2,
  6. E. Cobos2,
  7. W. M. Kast4,
  8. S. Ferrone5,
  9. M. Chiriva-Internati1,2
  1. 1Department of Microbiology and Immunology
  2. 2Internal Medicine, Texas Tech University Health Sciences Center and Southwest Cancer Treatment and Research Center, Lubbock, TX
  3. 3Scientific Direction, Istituto Clinico Humanitas, IRCCS, Rozzano, Milan, Italy
  4. 4Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA
  5. 5Department of Immunology, Roswell Park Cancer Institute, Buffalo, NY

Abstract

Purpose The correlation between expression of tapasin and HLA class I was studied in patients refractory to conventional treatment in multiple myeloma (MM). Regulation of tapasin and HLA class I expression could be suitable markers for prognostic factors of MM patients.

Methods Expression of mRNA for tapasin and HLA class I was evaluated via reverse transcription-polymerase chain reaction (RT-PCR) for 20 primary MM tumors and 6 MM cell lines. Protein analysis was performed using Western blots for protein expression of tapasin and HLA class I.

Summary HLA class I and tapasin were analyzed in a panel of 20 fresh primary MM tumors and 6 MM cell lines. In primary tumors, 50% do not express tapasin at the protein level but are positive for mRNA. Following standard treatment of MM, 50% do not express tapasin at the protein level and 30% do not express mRNA or protein. Restoration by IFN-g further suggests tapasin expression in MM is alternately due to dysregulation rather than structural alterations by mutation.

Conclusion These data indicate that absence of tapasin plays a central role in down-regulation of HLA class I in relapse MM patients. Tapasin and HLA class I down-regulation was prominent in relapsing patients compared to control. Deficiency of tapasin in tumor cells appears to be a frequent event in human tumors. Furthermore, tapasin and HLA class I down-regulation in MM was extensively associated with reduced survival of patients, therefore playing a role in poor prognosis of disease.

Statistics from Altmetric.com

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.