Orthotopic tumorgrafts in nude mice as a model to evaluate calcitriol effects in breast cancer / Modelo de enxerto tumoral ortotópico em camundongos para avaliar os efeitos do calcitriol em câncer de mama

Abstract Calcitriol antiproliferative effects were observed in xenografts of breast cancer cell lines, however they were not yet investigated in tumorgrafts, consisting of freshly collected breast cancer samples xenografted into animals. Objectives To establish a tumorgraft model, from freshly collected breast cancer samples, which were directly implanted in nude mice, to study calcitriol effects. Methods Breast cancer samples collected from 12 patients were orthotopically implanted into nude mice. Animals were treated with weekly intratumoral injections of calcitriol 3 μg/Kg, which was previously shown to induce peak serum calcitriol levels in the predicted therapeutic range. Results Success engraftment rate was 25%. Tumorgrafts were established from aggressive (HER2 positive or histological grade 3) highly proliferative samples and original tumor characteristics were preserved. Calcitriol highly induced its target gene, CYP24A1, indicating that the genomic vitamin D pathway is active in tumorgrafts. However, no differences in the expression of proliferation and apoptosis markers (BrdU incorporation, Ki67, CDKN1A, CDKN1B, BCL2 expression) were observed in these highly proliferative tumor samples. Conclusions Tumorgrafts seem a promising model to explore other calcitriol doses and regimens, considering the heterogeneity of the disease and microenvironment interactions.

Resumo Os efeitos antiproliferativos de calcitriol foram observados em xenotransplantes de linhagens celulares de câncer de mama, entretanto, não foram ainda investigados em enxertos tumorais, consistindo de implantes em animais de amostras de câncer de mama recém-coletadas. Objetivos Estabelecer modelo de enxerto tumoral, a partir de amostra de câncer de mama recém-coletada e diretamente implantada em camundongos nude, para estudar o efeito do calcitriol. Métodos Amostras de câncer de mama de 12 pacientes foram implantadas ortotopicamente em camundongos nude. Os animais foram tratados com injeção intratumoral semanal de calcitriol 3 μg/Kg, a qual foi previamente associada com indução de pico sérico de calcitriol dentro do intervalo de nível terapêutico. Resultados A taxa de sucesso de pega do enxerto foi de 25%. Os enxertos tumorais foram estabelecidos de tumores agressivos com alta taxa de proliferação (HER2 positivo ou grau histológico 3) e as características do tumor original foram preservadas. O calcitriol induziu fortemente a expressão do gene alvo, CYP24A1, indicando que a via genômica da vitamina D está ativa nos enxertos tumorais, entretanto, não se observou diferenças na expressão de marcadores de proliferação e apoptose (incorporação de BrdU, expressão de Ki67, CDKN1A, CDKN1B e BCL2) nestas amostras altamente proliferativas. Conclusões Os enxertos tumorais parecem ser um modelo promissor para explorar outros esquemas e doses de calcitriol, considerando a heterogeneidade da doença e interações com o microambiente.

Prognostic Value of ADAMTS Proteases and Their Substrates in Epithelial Ovarian Cancer

Background: ADAMTS are metalloproteases with disintegrin and thrombospondin motifs. They are secreted proteases playing a role in biological processes such as inflammation, angiogenesis, and urogenital development. ADAMTS have specific substrates, such as the proteoglycans (PG) versican, aggrecan, and brevican. Despite data indicating a role of ADAMTS in tumor invasion and metastases, effects played by these molecules in cancer progression are still controversial. In ovarian cancer, the importance of ADAMTS gene mutations was recently described and related to chemotherapy outcome. Objective: To analyze protein levels of ADAMTS-1, -4, and -5, and TIMP-3 in human ovarian cancer classified as benign, borderline, or malignant. We also assessed the expression of the ADAMTS substrates aggrecan, brevican, and versican in these neoplasms. Correlations between overall survival and protein expression were performed. Methods: Tumors were classified according to the WHO Classification of Tumors of Female Reproductive Organs. Protein and PG expression was studied by immunohistochemistry. Differences in labeling were analyzed by percent measurements of stained areas. Results: ADAMTS-1, ADAMTS-5, and its tissue inhibitor TIMP-3 are increased in borderline and malignant tumors compared to benign neoplasms. Aggrecan and versican levels were increased in malignant subtypes compared to benign ovarian cancer. Higher ADAMTS-1, TIMP-3, and versican expression was associated with a shorter overall survival. Conclusions: Comparison of protease, TIMP-3, and substrate expression showed that in malignant tumors all ADAMTS and TIMP-3 expression levels were significantly raised compared to the substrates studied.

p16 (INK4a) has clinicopathological and prognostic impact on oropharynx and larynx squamous cell carcinoma

CDKN2A encodes proteins such as p16 (INK4a), which negatively regulate the cell-cycle. Molecular genetic studies have revealed that deletions in CDKN2A occur frequently in cancer. Although p16 (INK4a) may be involved in tumor progression, the clinical impact and prognostic implications in head and neck squamous cell carcinoma (HNSCC) are controversial. The objective of this study was to evaluate the frequency of the immunohistochemical expression of p16 (INK4a) in 40 oropharynx and 35 larynx from HNSCC patients treated in a single institution and followed-up at least for 10 years in order to explore potential associations with clinicopathological outcomes and prognostic implications. Forty cases (53.3%) were positive for p16 (INK4a) and this expression was more intense in non-smoking patients (P = 0.050), whose tumors showed negative vascular embolization (P = 0.018), negative lymphatic permeation (P = 0.002), and clear surgical margins (P = 0.050). Importantly, on the basis of negative p16 (INK4a) expression, it was possible to predict a probability of lower survival (P = 0.055) as well as tumors presenting lymph node metastasis (P = 0.050) and capsular rupture (P = 0.0010). Furthermore, increased risk of recurrence was observed in tumors presenting capsular rupture (P = 0.0083). Taken together, the alteration in p16 (INK4a) appears to be a common event in patients with oropharynx and larynx squamous cell carcinoma and the negative expression of this protein correlated with poor prognosis.

Estrogen and progesterone receptors in human papilloma virus-related cervical neoplasia

Estrogen (ER) and progesterone (PR) receptors in the normal uterine cervix, cervical intraepithelial neoplasia and invasive carcinoma were studied in consecutive samples from Hospital do Câncer, São Paulo, between 1996 and 1997. Tissue was collected by removing a fragment of the tumoral area using a 5-mm diameter biopsy punch, followed by removal of a macroscopically normal area as close as possible from the tumor. Histopathological confirmation was obtained for all specimens analyzed. A total of 24 normal tissues, 17 cases of cervical intraepithelial neoplasia and 7 of invasive carcinomas were studied. The ER/PR ratio was determined by immunohistochemistry using monoclonal antibodies specific for each receptor. Adjacent tissue slides were submitted to generic PCR for human papillomavirus (HPV) DNA detection followed by typing by dot blot hybridization. About half (45.8 percent) of the tumors were HPV DNA positive while 29.1 percent of the patients were also HPV positive in their respective normal tissue. ER was negative in the tumoral epithelium of 11 HPV-positive patients (P = 0.04). There was a trend in the ER distribution in normal tissue that was opposite to that from lesions, but it was not statistically significant (P = 0.069). No difference in ER distribution in stromal tissues was observed between HPV-positive and HPV-negative tissues. PR staining was negative in the epithelium of all cases studied. The results obtained from this small number of cases cannot be considered to be conclusive but do suggest that factors related to viral infection affect the expression of these ER/PR cervix receptors.

Tumor endócrino de pâncreas associado a síndrome hipoglicêmica. Relato de caso e caracterização imuno-histoquímica

O artigo não apresenta resumo.

Expression of c-erbB-2, p53 and c-myc proteins in male breast carcinoma: Comparison with traditional prognostic factors and survival

There are few data evaluating biological markers for men with breast cancer. The purpose of the present study was to analyze the expression of the oncogenes c-erbB-2 and c-myc and of the suppressor gene p53 by immunohistochemical techniques in archival paraffin-embedded tissue blocks of 48 male breast cancer patients, treated at the A.C. Camargo Cancer Hospital, Säo Paulo, SP, Brazil. The results were compared with clinicopathological prognostic features. Immunopositivity of c-erbB-2, p53 and c-myc was detected in 62.5, 16.7 and 20.8 percent of the cases analyzed, respectively. Estrogen and progesterone receptors were positive in 75 and 69 percent of the cases, respectively. Increasing staging was statistically associated with c-erbB-2 (P = 0.04) and weakly related to p53 positivity (P = 0.06). No significant correlation between specific survival rate (determined by the log rank test) and the molecular markers analyzed was found, whereas the number of compromised lymph nodes and advanced TNM (tumor, node, metastasis) staging were associated with diminished survival