Involvement of HLA class I molecules in the immune escape of urologic tumors.
CONTEXT AND OBJECTIVE
To analyze the influence of different alterations in human leukocyte antigen class I molecules (HLA I) in renal cell carcinoma, as well as in bladder and prostate cancer. We also study the correlation between HLA I expression and the progression of the disease and the response after immunotherapy protocols.


EVIDENCES ACQUISITION
It has been shown, experimentally, that the immune system can recognize and kill neoplastic cells. By analyzing the expression of HLA I molecules on the surface of cancer cells, we were able to study the tumor escape mechanisms against the immune system.


EVIDENCES SYNTHESIS
Alteration or irreversible damage in HLA I molecules is used by the neoplastic cells to escape the immune system. The function of these molecules is to recognize endogenous peptides and present them to T cells of the immune system. There is a clear relationship between HLA I reversible alterations and success of therapy. Irreversible lesions also imply a lack of response to treatment. The immune system activation can reverse HLA I molecules expression in tumors with reversible lesions, whereas tumors with irreversible ones do not respond to such activation. Determine the type of altered HLA I molecules in tumors is of paramount importance when choosing the type of treatment to keep looking for therapeutic success. Those tumors with reversible lesions can be treated with traditional immunotherapy; however, tumour with irreversible alterations should follow alternative protocols, such as the use of viral vectors carrying the HLA genes to achieve damaged re-expression of the protein.


CONCLUSION
From studies in urologic tumors, we can conclude that the HLA I molecules play a key role in these tumors escape to the immune system.
['Carretero|R|R|', 'Gil-Julio|H|H|', 'Vázquez-Alonso|F|F|', 'Garrido|F|F|', 'Castiñeiras|J|J|', 'Cózar|J M|JM|']
D000951:Antigens, Neoplasm D001500:BCG Vaccine D002277:Carcinoma D005260:Female D015972:Gene Expression Regulation, Neoplastic D005805:Genes, MHC Class I D015395:Histocompatibility Antigens Class I D006801:Humans D007167:Immunotherapy D007680:Kidney Neoplasms D008297:Male D011471:Prostatic Neoplasms D016896:Treatment Outcome D019139:Tumor Escape D001749:Urinary Bladder Neoplasms D014571:Urologic Neoplasms
Human leukocyte antigen class i Renal cell carcinoma Prostate cancer Immunotherapy Antigenic processing Antígeno leucocitario humano de clase i Antígeno leucocitario humano de clase ii Bladder cancer Carcinoma de células renales Cáncer de próstata Cáncer de vejiga Fenotipos Human leukocyte antigen class ii Inmunoterapia Phenotypes Procesamiento antigénico