Indoleamine 2,3-dioxygenase and tryptophan 2,3-dioxygenase expression in HPV infection, SILs, and cervical cancer

Author(s)

Venancio, Paloma Almeida ^[1] ; Lopes Consolaro, Marcia Edilaine ^[2] ; Derchain, Sophie Francoise ^[3] ; Boccardo, Enrique ^[4] ; Villa, Luisa Lina ^[5] ; Maria-Engler, Silvya Stuchi ^[1] ; Campa, Ana ^[1] ; Discacciati, Michelle Garcia ^{[1, 3]}

Affiliation

^[1] Univ Sao Paulo, Sch Pharmaceut Sci, Dept Clin Anal & Toxicol, Sao Paulo - Brazil

^[2] Univ Estadual Maringa, Clin Cytol Lab, Maringa, Parana - Brazil

^[3] Univ Estadual Campinas, Sch Med Sci, Dept Obstet & Gynecol, Campinas, SP - Brazil

^[4] Univ Sao Paulo, Inst Biomed Sci, Dept Microbiol, Sao Paulo - Brazil

^[5] Univ Sao Paulo, Dept Radiol & Oncol, Fac Med, Sao Paulo - Brazil

• Document type: Journal article
• Source: CANCER CYTOPATHOLOGY; v. 127, n. 9 AUG 2019.
• Web of Science Citations: 0

Abstract

Background Human papillomavirus (HPV) infection is the central factor for cervical cancer, whereas epithelial immune mechanisms contribute to the progression of HPV infection and its associated lesions. The authors evaluated the expression of indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) in cervicovaginal samples from women with normal cervical epithelium or with different degrees of squamous intraepithelial lesions (SILs) and cervical cancer. Methods IDO expression was analyzed by immunocytochemistry in liquid-based cytology samples from 165 women, of whom 42 had cervical changes subclassified as low-grade SIL (n = 6), high-grade SIL (n = 30), or squamous cell carcinoma (SCC) (n = 6), and 123 had negative Papanicolaou smears. IDO and TDO expression also were analyzed by immunohistochemistry, and HPV and other genital pathogens were evaluated by polymerase chain reaction analysis. Results Low IDO expression was observed in normal cervical epithelium irrespective of HPV status. Increased numbers of IDO-positive squamous cells and IDO-positive leukocytes were observed in women with SIL or SCC. TDO expression was detected in leukocytes infiltrating the stroma around intraepithelial or invasive cervical lesions. Higher IDO levels were detected in organotypic epithelial cultures established from keratinocytes transduced with the HPV16 E6/E7 oncoproteins. Conclusions The upregulation of IDO expression in leukocytes and squamous cells in HPV-associated SIL and SCC suggests that immunosuppressive mechanisms involving tryptophan metabolism may have a role in cervical carcinogenesis. Although previous studies have suggested the role of IDO in HPV pathogenesis, this is the first evidence of TDO involvement in the process. Furthermore, the current data emphasize the role of leukocytes, especially neutrophil-like cells, as an IDO source. (AU)

• FAPESP's process: 12/09746-2 - Relationship between MMP-9 and RECK expression in abnormal cervical smears and clinical evolution of squamous intraepithelial lesion
• Grantee: Michelle Garcia Discacciati de Carvalho
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 17/04926-6 - Melanoma and chemoresistance: in vitro and in silico models to exploit therapeutic targets
• Grantee: Silvya Stuchi Maria-Engler
• Support Opportunities: Research Projects - Thematic Grants