ABSTRACT
Receptor tyrosine kinase (RTK) activity may contribute to carcinogenesis. The c-Kit receptor, a member of the RTK family, is expressed in immature haematopoietic system cells. Acute lymphoblastic leukaemia (ALL) presents incompletely differentiated lymphoblasts, and consequently, c-Kit expression can be detected in these cells. The BCR-ABL kinase, which is usually present in both ALL and chronic myeloid leukaemia, can trigger signalling pathways with neoplastic effects. However, a certain number of ALL patients and chronic myeloid leukaemia patients do not express this kinase, raising the question of which other proteins that intervene in signalling pathways may be involved in the development of these diseases. OBJECTIVES: To test whether c-Kit has proliferative effects and affects the inhibition of apoptosis of leukaemic lymphoblasts that do not express BCR-ABL. METHODS: We cultured RS4:11 lymphoblasts and analysed the expression and activation of c-Kit by immunofluorescence, and flow cytometry, evaluation of cell proliferation, apoptosis, cyclin D1 and Bak expression were carried out by flow cytometry; activation of AKT and survivin expression were tested by immunoblot. RESULTS: The c-Kit receptor was found to induce proliferation and to increase the expression of cyclin D1 via the PI3K/AKT/NF-kB signalling pathway. Additionally, the c-Kit/PI3K/AKT pathway increased the inhibition of apoptosis and survivin expression. Similarly, c-Kit was observed to reduce the expression of the pro-apoptotic Bak protein. CONCLUSION: These results suggest that, in leukaemic lymphoblasts, c-Kit triggers a signalling pathway with proliferative and anti-apoptotic effects; information to this effect has not yet been reported in the literature.
Subject(s)
Apoptosis , Blast Crisis/metabolism , Cell Proliferation , Gene Expression Regulation, Leukemic , Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolism , Proto-Oncogene Proteins c-kit/biosynthesis , Signal Transduction , Blast Crisis/pathology , Cell Line, Tumor , Humans , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathologyABSTRACT
Adequate management of phyllodes tumors of the breast (PTB) remains a challenge because of the difficulty in correctly establishing preoperative diagnosis. The aim of this study was to evaluate the usefulness of Ki-67, CD10, CD34, p53, CD117, and of the number of mast cells in the differential diagnosis of benign PTB and cellular fibroadenomas (CFs) as well as in the grading of PTB. Fifty-one primary PTB and 14 CFs were examined by immunohistochemistry.When evaluating CD117 expression, higher epithelial expression was present in CF as well as an increased number of mast cells in benign PTB. Stromal expression of Ki-67, CD10, CD34, and p53 were relevant to PTB grading, of which the first 3 showed significance in the distinction of benign and borderline PTB, as well as between benign and malignant PTB. P53 was relevant only for the discrimination between benign and malign PTB. None of the markers showed significance in distinguishing between borderline and malign PTB.
Subject(s)
Biomarkers, Tumor/analysis , Breast Neoplasms/diagnosis , Fibroadenoma/diagnosis , Mast Cells/pathology , Phyllodes Tumor/diagnosis , Adolescent , Adult , Aged , Antigens, CD34/analysis , Antigens, CD34/biosynthesis , Breast Neoplasms/classification , Diagnosis, Differential , Female , Fibroadenoma/classification , Humans , Immunohistochemistry , Ki-67 Antigen/analysis , Ki-67 Antigen/biosynthesis , Middle Aged , Neprilysin/analysis , Neprilysin/biosynthesis , Phyllodes Tumor/classification , Proto-Oncogene Mas , Proto-Oncogene Proteins c-kit/analysis , Proto-Oncogene Proteins c-kit/biosynthesis , Tumor Suppressor Protein p53/analysis , Tumor Suppressor Protein p53/biosynthesis , Young AdultABSTRACT
Biologic agents targeting oncogenes have encourage researchs trying to correlate the role of tyrosine kinase in the pathogenesis of tumours. Osteosarcoma is a high grade aggressive neoplasm with poor survival. Our aim was to investigate c-kit immunoexpression, its prognostic relevance for patients with osteosarcoma, and the effect of imatinib mesylate (STI571) on proliferation and invasion of the human osteosarcoma cell line.A retrospective immunohistochemical study was performed on archival formalin-fixed paraffin-embedded specimens from 52 patients with high-grade primary osteosarcoma of extremities treated at the Pediatric Oncology Institute (IOP, GRAAC) and archived in the Department of Pathology, Federal University of São Paulo. Only pre-chemotherapy specimens were analyzed. Strongly stained cytoplasm and membrane cells were taken as positive. Human osteosarcoma cells from line MG-63 were incubated and the inhibitory effect of imatinib mesylate (STI571) on cell proliferation and invasion was studied. In 24 cases (46.15%), c-kit was expressed by the cells and c-kit-positive tumors exhibited lower necrosis post-chemotherapy. No correlation was found between c-kit expression and overall and disease-free survival. Imatinib mesylate decreased the rates of cell growth of osteosarcoma cells in low doses and invasion in high doses C-kit-positive tumors had worse response to chemotherapy and imatinib mesylate can play a role in blocking or decreasing the rate of growth of osteosarcoma cells, but not the invasive capacity of these neoplastic cells. These data suggested that imatinib mesylate could be a therapeutic target of strategies against osteosarcoma tumors. Further studies are necessary to confirm this indication.
Subject(s)
Biomarkers, Tumor/analysis , Bone Neoplasms/metabolism , Osteosarcoma/metabolism , Proto-Oncogene Proteins c-kit/biosynthesis , Antineoplastic Agents/pharmacology , Benzamides , Bone Neoplasms/drug therapy , Bone Neoplasms/pathology , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , Disease-Free Survival , Female , Humans , Imatinib Mesylate , Immunohistochemistry , In Vitro Techniques , Kaplan-Meier Estimate , Male , Osteosarcoma/drug therapy , Osteosarcoma/pathology , Piperazines/pharmacology , Prognosis , Pyrimidines/pharmacology , Retrospective StudiesABSTRACT
Objective: To evaluate the expression of c-kit in breast invasive ductal carcinomas (IDC) and metastasis to lymph nodes considering epithelial and stromal components separately and correlate this variable to others clinical, pathological and biological markers (EGFR, Her-2, ER, PR, Ki-67 and p53 expression). Methods: We analysed 80 IDC, stage T2-T4 Nx Mx, in TMA of epithelial, stromal component and lymph nodes. Statistical analysis considered significant a p value < 5%. Results: c-kit expression was founded in 9 cases in epithelial component (11.3%) and in 10 cases (12.5%) of stromal component. The 43 samples of lymph nodes metastasis were negative. EGFR and Her-2 were predominantly negative, both in epithelial (77.5% and 73.75%, respectively), as stromal (97.5% and 95.0%) components and metastasis to lymph nodes (83.7% and 62.8%). While ER, PR, Ki-67 and p53 were positive in 49 (61.0%), 40 (53.0%), 67 (83.75%) and 59 cases (73.75%) in the epithelial component. Stromal cells have proved negatives. c-kit epithelial expression correlated to presence of in situ component (p = 0.044) and stromal c-kit expression correlated to presence of necrosis (p = 0.002). There was no association between c-kit expression and staging and biological markers. Transformed epithelial cells at me lymph nodes metastasis stained for ER, PR, Ki-67 and p53 in 27 (62.8%), 16 (37.5%), 41 (95.0%) and 28 cases (65.1%), respectively. Conclusions: The expression of c-kit is mostly negative in primary IDC both in the epithelial and stromal component, as well as in lymph node metastasis. The lack of correlation between c-kit and others tyrosine kinase proteins suggest that they are independently regulated. Metastasis for Iymph nodes were not c-kit positive and further studies of mutations of c-kit and his family, correlate with other prognostic factors and survival required to reveal the exact mechanism of action of this molecule in breast cancer.
Objetivo: Avaliar a expressão de c-kit em células epiteliais, estromais e metástases para linfonodos de carcinomas ductais mamários invasivos (CDI) e correlacionar essa variável com os outros marcadores clínicos, patológicos e biológicos (EGFR, HER-2, RE, RP, Ki-67 e p53). Métodos: Analisaram-se 80 CDI, estádios T2-T4 Nx Mx, em TMA de componente epitelial, estromal e linfonodos. O valor de p < 5% foi considerado significante. Resultados: A expressão de c-kit foi encontrada em 9 casos no componente epitelial (11,3%) e em 10 casos (12,5%) do componente estromal. As 43 amostras de metástases para linfonodos foram negativas. EGFR e Her-2 foram predominantemente negativos, tanto em epitélio (77,5% e 73,75%, respectivamente), como estroma (97,5% e 95,0%) e metástases para linfonodos (83,7% e 62,8%), enquanto RE, RP, Ki-67 e p53 foram positivos em 49 (61,0%), 40 (53,0%), 67 (83,75%) e 59 casos (73,75%) no componente epitelial. Células do estroma se mostraram negativas. A expressão de c-kit epitelial correlacionou-se com a presença do componente in situ (p = 0,044) e a expressão de c-kit no estroma se associou com a presença de necrose (p = 0,002). Não houve associação entre a expressão de c-kit com estadiamento e marcadores biológicos. Células epiteliais transformadas de metástases para linfonodos coraram para RE, RP, Ki-67 e p53 em 27 (62,8%), 16 (37,5%),41 (95,0%) e 28 casos (65,1%), respectivamente. Conclusões: A expressão de c-kit é majoritariamente negativa em CDI primário tanto no componente epitelial quanto no estromal, assim como em metástases linfonodais. A falta de correlação entre o c-kit e outras proteínas tirosina quinases sugere que elas sejam reguladas de forma independente. Metástases para linfonodos não foram positivas para c-kit, e estudos posteriores de mutações do c-kit e sua família, correlacionando com outros fatores prognósticos e sobrevida, são necessários para revelar o exato mecanismo de ação dessa molécula no câncer de mama.
Subject(s)
Humans , Carcinoma, Ductal, Breast/genetics , Carcinoma, Ductal, Breast/pathology , Epithelial Cells/pathology , Stromal Cells/pathology , Immunohistochemistry , Biomarkers/metabolism , Proto-Oncogene Proteins c-kit/biosynthesis , Neoplasm Staging , Breast Neoplasms/pathologyABSTRACT
We estimated by quantitative flow cytometry (FC) the expression of CD13, CD33, CD34 and CD117 antigens in cells from 64 patients with acute myeloid leukaemia (AML) and 22 normal bone marrows (BMs). The method converts fluorescence intensity into number of antigen molecules per cell, measured by antibody binding capacity (ABC). The number of molecules per cell in normal BM was 9.5+/-5.7 for CD13, 7+/-2.3 for CD33, 6+/-0.7 for CD34, and 6.3+/-1.5x10(3) for CD117. AML blasts expressed 11.4+/-12.4 molecules per cell for CD13, 9.5+/-9.7 for CD33, 74+/-2328.5 for CD34 and 12.5+/-33 x 10(3) for CD117. The number of CD34 and CD117 molecules were significantly higher in AML than in normals (P<0.0001 and P<0.05, respectively) while only in a few cases, CD13 and CD33 were abnormally expressed in myeloblasts. Our results indicate that quantitative analysis of CD34 and CD117 may be useful to detect minimal residual disease (MRD) and could be tested in a future to monitor therapy in AML.
Subject(s)
Antigens, CD34/biosynthesis , Biomarkers, Tumor/biosynthesis , Leukemia, Myeloid/genetics , Neoplasm Proteins/analysis , Neoplastic Stem Cells/chemistry , Proto-Oncogene Proteins c-kit/biosynthesis , Adolescent , Adult , Aged , Aged, 80 and over , Antigens, CD34/genetics , Biomarkers, Tumor/genetics , Child , Child, Preschool , Female , Gene Expression Regulation, Leukemic , Humans , Leukemia, Myeloid/diagnosis , Leukemia, Myeloid/pathology , Male , Middle Aged , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/genetics , Neoplasm, Residual , Proto-Oncogene Proteins c-kit/geneticsABSTRACT
Cell-cell interaction is important in the expansion of leukemic cells and of solid tumors. Steel factor (SF) or Kit ligand is produced as a membrane-bound form (mSF) and a soluble form. Because both primary gynecological tumors and primary leukemic cells from patients with acute myeloblastic leukemia (AML) have been shown to coexpress c-Kit and SF, we addressed the question of whether mSF could contribute to cell interaction in these cancers. Investigations on primary cervical carcinomas have been hindered by the fact that the cells do not grow in culture. We report herein the establishment of two cervical carcinoma cell lines, CALO and INBL, that reproduce the pattern of SF/c-Kit expression observed in primary tumor samples. In addition, these cells exhibit marked density-dependent growth much in the same way as AML blasts. Using an antisense strategy with phosphorothioate-modified oligonucleotides that specifically target SF without affecting other surface markers, we provide direct evidence for a role of mSF and c-Kit in cell interaction and cell survival in these gynecological tumor cell lines as well as in primary AML blasts. Finally, our study defines the importance of juxtacrine stimulation, which may be as important, if not more, than autocrine stimulation in cancers.