Celso di Loreto

HPV16 oncoproteins induce MMPs/RECK-TIMP-2 imbalance in primary keratinocytes: possible implications in cervical carcinogenesis.

Cervical cancer is the third most common cancer in women worldwide. Persistent infection with high-risk HPV types, principally HPV16 and 18 is the main risk factor for the development of this malignancy. However, the onset of invasive tumor occurs many years after initial exposure in a minority of infected women. This suggests that other factors beyond viral infection are necessary for tumor establishment and progression. Tumor progression is characterized by an increase in secretion and activation of matrix metalloproteinases (MMPs) produced by either the tumor cells themselves or tumor-associated fibroblasts or macrophages. Increased MMPs expression, including MMP-2, MMP-9 and MT1-MMP, has been observed during cervical carcinoma progression. These proteins have been associated with degradation of ECM components, tumor invasion, metastasis and recurrence. However, few studies have evaluated the interplay between HPV infection and the expression and activity of MMPs and their regulators in cervical cancer. We analyzed the effect of HPV16 oncoproteins on the expression and activity of MMP-2, MMP-9, MT1-MMP, and their inhibitors TIMP-2 and RECK in cultures of human keratinocytes. We observed that E7 expression is associated with increased pro-MMP-9 activity in the epithelial component of organotypic cultures, while E6 and E7 oncoproteins co-expression down-regulates RECK and TIMP-2 levels in organotypic and monolayers cultures. Finally, a study conducted in human cervical tissues showed a decrease in RECK expression levels in precancer and cancer lesions. Our results indicate that HPV oncoproteins promote MMPs/RECK-TIMP-2 imbalance which may be involved in HPV-associated lesions outcome.

RKIP Inhibition in cervical cancer Is associated with higher tumor aggressive behavior and resistance to cisplatin therapy

Cervical cancer is one of the most common cancers in women worldwide, being high-risk group the HPV infected, the leading etiological factor. The raf kinase inhibitory protein (RKIP) has been associated with tumor progression and metastasis in several human neoplasms, however its role on cervical cancer is unclear. In the present study, 259 uterine cervix tissues, including cervicitis, cervical intraepithelial lesions and carcinomas, were analyzed for RKIP expression by immunohistochemistry. We found that RKIP expression was significantly decreased during malignant progression, being highly expressed in non-neoplastic tissues (54% of the samples; 73/135), and expressed at low levels in the cervix invasive carcinomas (∼15% (19/124). Following in vitro downregulation of RKIP, we observed a viability and proliferative advantage of RKIP-inhibited cells over time, which was associated with an altered cell cycle distribution and higher colony number in a colony formation assay. An in vitro wound healing assay showed that RKIP abrogation is associated with increased migratory capability. RKIP downregulation was also associated with an increased vascularization of the tumors in vivo using a CAM assay. Furthermore, RKIP inhibition induced cervical cancer cells apoptotic resistance to cisplatin treatment. In conclusion, we described that RKIP protein is significantly depleted during the malignant progression of cervical tumors. Despite the lack of association with patient clinical outcome, we demonstrate, in vitro and in vivo, that loss of RKIP expression can be one of the factors that are behind the aggressiveness, malignant progression and chemotherapy resistance of cervical cancer.

Estudo preliminar do SISCOLO-Qualidade na rede de saúde pública de São Paulo

The aim of the present work was to analyses critically the preliminary results of the computerized Quality System of gynecologycal cytology, implanted by the Public Health Ministry of Brazil - SISCOLO. Cervicovaginal smears stained by the Papanicolaou method were utilized. These smears were obtained through the diagnostic routine undertaken at the Oncocentro Foundation Pathology Laboratory of pathology, comprising cases of March 2000. Such cases were rescreened in a blind study, by the staff of the Pathology Division of the SP Adolpho Lutz Institutes Cytology Section. The SISCOLO-Quality Program selects, among all cases analyzed in the period, all such positive cases (ASCUS, AGUS, CIN and carcinomas) and to complete 10% of all cases it selects all non-satisfying and negative cases at random. From the 8,370 cases selected in March 2000, the SISCOLO-Quality program selected 837 samples. Among the selected samples, 23,4% showed squamo-columnar junction material, 5% were considered non-satisfactory for diagnosis and 71.1%, satisfactory although limited. The rescreening analysis showed concordance in 86.62% of the cases, one grade discordance was observed in 12.42% and two or more grades discordance in 0.96% of the cases. We concluded that the SISCOLO-Quality Program has applicability in the health public system as external monitoring method and meets the Health Ministrys expectations.

Expressão imuno-histoquímica dos marcadores pcna, KI67 e p53 em carcinomas epidermóides do trato aerodigestivo superior

OBJETIVO: Os carcinomas epidermoides do trato aerodigestivo superior sao tumores de comportamento biologico heterogeneo. O objetivo deste trabalho e verificar se a expressao imuno-histoquimica dos marcadores Ki67, PCNA e P53 apresenta correlacoes com parâmetros prognosticos clinico-patologicos. METODOS: Determinacao da expressao imuno-histoquimica dos antigenos Ki67, PCNA e P53 em especimes tumorais fixados e embebidos em parafina de 53 pacientes com carcinoma epidermoide em diferentes sitios primarios do trato aerodigestivo superior. RESULTADOS: Os marcadores tiveram altos indices de expressao imuno-histoquimica, sendo 46,5% para o Ki67, 66,5% para o PCNA e 36,5% para o P53. Nao houve correlacao da expressao do Ki67 e do PCNA com o estadiamento TNM (AJCC), nem com o grau de malignidade. A expressao do Ki67 apresentou correlacao positiva com a expressao do PCNA (p = 0,037). O mesmo aconteceu para o PCNA e o numero de mitoses por campo (p = 0,001). CONCLUSOES: De acordo com estes resultados, concluiu-se que a determinacao da imunorreatividade dos marcadores Ki67 e PCNA e um metodo objetivo e quantificavel para avaliar proliferacao celular que pode subsidiar as informacoes prognosticas.

Revisão de esfregaços cervicais negativos em pacientes com lesöes intra-epiteliais de alto grau

Within the strategies of internal quality control, the review of previous negative Papanicolaou smears from patients with diagnosis of CIN 2 or CIN 3 is considered one of the most efficient for detection of false negative results. In the present study we reviewed the previous negative smears of cases with diagnosis of CIN 2 or CIN 3 during the years of 1998 and 1999. During this period the Adolfo Lutz Institute has performed 113.619 Papanicolaou tests; 233 cases were diagnosed as CIN 2 or CIN 3. The cases diagnosed as unsatisfactory were excluded. Among the 36 cases from which there were previous smears in the period of 36 months before the original diagnosis, we found 22 cases of CIN (12 CIN 1, seven CIN 2 and three CIN 3) and 14 cases diagnosed as inflammatory or normal. When those 14 smears were reviewed, the following diagnosis were found: unsatisfactory (two cases), inflammatory (five cases), Ascus (three cases), CIN 1 (three cases), CIN 2 (one case). In conclusion, the review of previous negative Papanicolaou smears is a highly efficient strategy in order to detect false negative results. This practice can be useful as a guide for continued education measures.

Avaliação crítica das nomenclaturas diagnósticas dos exames citopatológicos cervicais utilizadas no Sistema Único de Saúde (SUS)

PURPOSE: to identify the nomenclature for reporting cervical cytological diagnoses used by laboratories which render services to the Brazilian Unified Health System (SUS) and which participate in External Quality Monitoring (MEQ). To evaluate the information acquired from gynecologists of the SUS regarding the various diagnostic classifications that they receive in the cervical cytology diagnostic reports. METHODS: we evaluated 94 cytology reports issued by laboratories which participate in the MEQ in the State of Sao Paulo, Brazil, and 126 questionnaires applied to gynecologists who work for the SUS. RESULTS: out of the 94 laboratories, 81 (86.2%) use one diagnostic classification: 79 (97.6%) use the Brazilian Nomenclature for Cytological Reports (NBLC), 1 (1.2%) uses the Papanicolaou classification and 1 (1.2%) uses the Richart diagnostic classification. Of the 13 (13.8%) laboratories that use more than one classification, 5 use 2 types and 8 use 3 to 4 types, with 9 including the Papanicolau diagnostic classification. The study showed that 52 (55.3%) laboratories presented more than one descriptive diagnosis in the same report. Out of the 126 gynecologists who filled out a questionnaire evaluating the cytopathology reports, 78 (61.9 %) stated that they received laboratory reports with only one diagnostic classification, 48 (38.1%) received reports with more than one classification and 2 received reports with all 4 classifications. Among the 93 (73.8%) gynecologists who prefer only one classification, 56 (60.2%) claimed that the NBLC contributes to clinical practice, 13 (14.0%) opted for the Richart classification, 8 (8.6%) for the Reagan classification and 16 (17.2%) for the Papanicolaou classification. Out of 33 (26.2%) gynecologists who prefer more than one classification, 5 opted for the 4 classifications. CONCLUSIONS: these data suggest that there is still resistance on the part of pathologists about using the official nomenclature in cytology reports for SUS. There is discrepancy between the information that gynecologists would like to see in the reports and the information provided by the pathologists. Greater efforts should be made to stimulate the use of the official nomenclature.