ABSTRACT
BACKGROUND: Persistent high risk HPV infection can lead to cervical cancer, the second most common malignant tumor in women worldwide. NK cells play a crucial role against tumors and virus-infected cells through a fine balance between activating and inhibitory receptors. Expression of triggering receptors NKp30, NKp44, NKp46 and NKG2D on NK cells correlates with cytolytic activity against tumor cells, but these receptors have not been studied in cervical cancer and precursor lesions. The aim of the present work was to study NKp30, NKp46, NKG2D, NKp80 and 2B4 expression in NK cells from patients with cervical cancer and precursor lesions, in the context of HPV infection. METHODS: NKp30, NKp46, NKG2D, NKp80 and 2B4 expression was analyzed by flow cytometry on NK cells from 59 patients with cervical cancer and squamous intraepithelial lesions. NK cell cytotoxicity was evaluated in a 4 hour CFSE/7-AAD flow cytometry assay. HPV types were identified by PCR assays. RESULTS: We report here for the first time that NK cell-activating receptors NKp30 and NKp46 are significantly down-regulated in cervical cancer and high grade squamous intraepithelial lesion (HGSIL) patients. NCRs down-regulation correlated with low cytolytic activity, HPV-16 infection and clinical stage. NKG2D was also down-regulated in cervical cancer patients. CONCLUSION: Our results suggest that NKp30, NKp46 and NKG2D down-regulation represent an evasion mechanism associated to low NK cell activity, HPV-16 infection and cervical cancer progression.
Subject(s)
Killer Cells, Natural/immunology , NK Cell Lectin-Like Receptor Subfamily K/biosynthesis , Natural Cytotoxicity Triggering Receptor 1/biosynthesis , Natural Cytotoxicity Triggering Receptor 3/biosynthesis , Uterine Cervical Neoplasms/immunology , Adult , Antigens, CD/biosynthesis , Carcinoma, Squamous Cell/immunology , Carcinoma, Squamous Cell/virology , Cytotoxicity, Immunologic , Down-Regulation , Female , Flow Cytometry , Human papillomavirus 16/immunology , Human papillomavirus 16/isolation & purification , Humans , K562 Cells , Lectins, C-Type , Middle Aged , Papillomavirus Infections/immunology , Papillomavirus Infections/virology , Receptors, Immunologic/biosynthesis , Receptors, Natural Killer Cell/biosynthesis , Signaling Lymphocytic Activation Molecule Family , Uterine Cervical Neoplasms/virology , Uterine Cervical Dysplasia/immunology , Uterine Cervical Dysplasia/virologyABSTRACT
OBJECTIVE: Protease-activated receptor-2 (PAR-2) is a G-protein-coupled receptor that is cleaved and activated by trypsin and tryptase. There is evidence that PAR-2 contributes to tumor progression in stomach, colon, pancreas, prostate and breast cancer patients. However, the role of PAR-2 in cervical cancer is still unknown. The aim of this work was to study the PAR-2 expression in cervical cancer tissues and the effect of PAR-2 activation on cervical cancer proliferation. METHODS: Immunohistochemistry was used to analyze PAR-2 expression in fixed paraffin-embedded tumor tissue from 16 patients with invasive cervical cancer. HPV types were identified by PCR. PAR-2 expression in UISO-SQC-1, HeLa, SiHa, CasKi and C-33 A cervical cancer cell lines was evaluated by flow cytometry. Trypsin was detected by Western blot. Tumor proliferation in response to trypsin or agonist peptide was evaluated by the MTT method. RESULTS: A strong correlation between trypsin and PAR-2 expression in five cervical cancer cell lines, in association with proliferative growth in the presence of trypsin or agonist peptide, was found. All tumors from cervical cancer patients expressed PAR-2 (immunoreactive score was higher in poorly differentiated tumors). CONCLUSIONS: Results suggest that trypsin and PAR-2 are involved in cervical cancer cell proliferation.
Subject(s)
Carcinoma, Squamous Cell/metabolism , Receptor, PAR-2/biosynthesis , Uterine Cervical Neoplasms/metabolism , Alphapapillomavirus/genetics , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/virology , Cell Growth Processes/drug effects , Cell Growth Processes/physiology , Cell Line, Tumor , Female , Flow Cytometry , HeLa Cells , Humans , Immunohistochemistry , Neoplasm Staging , Papillomavirus Infections/metabolism , Papillomavirus Infections/pathology , Paraffin Embedding , Polymerase Chain Reaction , Trypsin/biosynthesis , Trypsin/pharmacology , Uterine Cervical Neoplasms/pathology , Uterine Cervical Neoplasms/virologyABSTRACT
Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is an adhesion molecule expressed in a wide variety of tissues including epithelial cells, leukocytes, and tumors that may establish both homotypic and heterotypic interactions. The aim of this work was to study the protein expression pattern of CEACAM1 in cervical cancer and precursor lesions in the context of human papillomavirus (HPV) infection. We used immunohistochemistry to analyze CEACAM1 expression in formalin-fixed, paraffin-embedded cervical tissues from 15 healthy women, 15 patients with low-grade squamous intraepithelial lesions (SIL), 15 patients with high-grade SIL, and 15 patients with squamous carcinomas. HPV types were identified by PCR. CEACAM1 was either undetectable (13/15) or low (2/15) in normal cervical tissues. By contrast, CEACAM1 expression was increased in high-grade SIL (10 samples staining intermediate/high and 4 samples staining low) as compared with low-grade SIL with undetectable (n=3) or low (n=12) expression. CEACAM1 expression was undetectable or low in cervical carcinoma. Our results suggest that CEACAM1 may be an interesting progression marker in SIL and cervical cancer, in particular due to reported immunoregulatory properties.
