PURPOSE: Critical to the success of active immunotherapy against cancer is the identification of immunologically recognized cancer-specific proteins with low tolerogenic potential. Cancer testis antigens (CTA), in particular, fulfill this requirement as a result of their aberrant expression restricted to cancer cells and lack of expression in normal tissues bypassing tolerogenic mechanisms against self. Although CTAs have been extensively studied in solid malignancies, little is known regarding their expression in chronic lymphocytic leukemia (CLL). EXPERIMENTAL DESIGN: Using a two-pronged approach we evaluated the immunogenicity of 29 CTAs in 22 patients with CLL and correlated these results to reverse transcriptase PCR data from CLL cell lines and patient cells. RESULTS: We identified IgG-specific antibodies for one antigen, NXF2, and confirmed this response by ELISA and Western blot. We found that treatment of CLL with 5-aza-2'-deoxycytidine can induce expression of NXF2 that lasted for several weeks after treatment. Treatment also increased levels of MHC and costimulatory molecules (CD80, CD86, and CD40) necessary for antigen presentation. In addition, we identified other promising antigens that may have potential immunotherapeutic application. CONCLUSIONS: Our findings suggest that NXF2 could be further pursued as an immunotherapeutic target in CLL, and that treatment with demethylating agents could be exploited to specifically modulate CTA expression and effective antigen presentation in malignant B cells.
PURPOSE: Critical to the success of active immunotherapy against cancer is the identification of immunologically recognized cancer-specific proteins with low tolerogenic potential. Cancer testis antigens (CTA), in particular, fulfill this requirement as a result of their aberrant expression restricted to cancer cells and lack of expression in normal tissues bypassing tolerogenic mechanisms against self. Although CTAs have been extensively studied in solid malignancies, little is known regarding their expression in chronic lymphocytic leukemia (CLL). EXPERIMENTAL DESIGN: Using a two-pronged approach we evaluated the immunogenicity of 29 CTAs in 22 patients with CLL and correlated these results to reverse transcriptase PCR data from CLL cell lines and patient cells. RESULTS: We identified IgG-specific antibodies for one antigen, NXF2, and confirmed this response by ELISA and Western blot. We found that treatment of CLL with 5-aza-2'-deoxycytidine can induce expression of NXF2 that lasted for several weeks after treatment. Treatment also increased levels of MHC and costimulatory molecules (CD80, CD86, and CD40) necessary for antigen presentation. In addition, we identified other promising antigens that may have potential immunotherapeutic application. CONCLUSIONS: Our findings suggest that NXF2 could be further pursued as an immunotherapeutic target in CLL, and that treatment with demethylating agents could be exploited to specifically modulate CTA expression and effective antigen presentation in malignant B cells.
Authors: Jason A Dubovsky; Daniel Wang; John J Powers; Emmanuel Berchmans; Matthew A Smith; Kenneth L Wright; Eduardo M Sotomayor; Javier A Pinilla-Ibarz Journal: Leuk Res Date: 2010-09-22 Impact factor: 3.156
Authors: Jason A Dubovsky; John J Powers; Yang Gao; Luis F Mariusso; Eduardo M Sotomayor; Javier A Pinilla-Ibarz Journal: Leuk Res Date: 2011-03-05 Impact factor: 3.156
Authors: Carolin Bier; Shirley K Knauer; Alexander Klapthor; Andrea Schweitzer; Alexander Rekik; Oliver H Krämer; Rolf Marschalek; Roland H Stauber Journal: J Biol Chem Date: 2010-11-17 Impact factor: 5.157
Authors: Yiming Zhong; Shuai Dong; Ethan Strattan; Li Ren; Jonathan P Butchar; Kelsey Thornton; Anjali Mishra; Pierluigi Porcu; J Michael Bradshaw; Angelina Bisconte; Timothy D Owens; Erik Verner; Ken A Brameld; Jens Oliver Funk; Ronald J Hill; Amy J Johnson; Jason A Dubovsky Journal: J Biol Chem Date: 2015-01-15 Impact factor: 5.157