The c-erbB-2 proto-oncogene encodes a 185kDa protein p!85, which belongs to epidermal growth factor receptor family. Amplification of this gene has been shown to correlate with poor clinical prognosis for certain canc...The c-erbB-2 proto-oncogene encodes a 185kDa protein p!85, which belongs to epidermal growth factor receptor family. Amplification of this gene has been shown to correlate with poor clinical prognosis for certain cancer patients. The monoclonal antibody A21 which directed against p185 specifically inhibits proliferation of tumor cells overexpressing p185, hence allows it to be a candidate for targeted therapy. In order to overcome several drawbacks of murine MAb, we cloned its VH and VL genes and constructed the single-chain Fv (scFv) through a peptide linker. The recombinant scFvA21 was expressed in Escherichia coli and purified by the affinity column. Subsequently it was characterized by ELISA, Western blot, cell immunohistochemistry and FACS. All these assays showed the binding activity to extracellular domain (ECD) of p!85. Based on those properties of scFvA21, we further constructed the scFv-Fc fusion molecule with a homodimer form and the recombinant product was expressed in mammalian cells. In a series of subsequent analysis this fusion protein showed identical antigen binding site and activity with the parent antibody. These anti-p185 engineered antibodies have promised to be further modified as a tumor targeting drugs, with a view of application in the diagnosis and treatment of human breast cancer.展开更多
We have developed and tested chimeric T-cell receptors (TCR) specific for p185HER2. In these experiments, retroviral vectors expressing the N29γ or N29ζ receptors were constructed in pRET6. Amphotropic viral produce...We have developed and tested chimeric T-cell receptors (TCR) specific for p185HER2. In these experiments, retroviral vectors expressing the N29γ or N29ζ receptors were constructed in pRET6. Amphotropic viral producer cells were established in the GALV-based PG13 packaging cell line. Ficoll purified human peripheral blood lymphocytes (PBL) were virally transduced using an optimized protocol incorporating activation with immobilized anti-CD3/anti-CD28 monoclonal anti- bodies, followed by viral infection in the presence of fibronectin fragment CH296. Transduced cells were co-cultured with human tumor cell lines that overexpress (SK-OV-3) or underexpress (MCF7) p185HER2 to assay for antigen specific im- mune responses. Both CM+ and CD8+ T-cells transduced with the N29γ or N29ζ chTCR demonstrated HER2-specific anti- gen responses, as determined by release of Th1 like cytokines, and cellular cytotoxicity assays. Our results support the fea- sibility of adoptive immunotherapy with genetically modified T-cells expressing a chTCR specific for p185HER2.展开更多
Objective: Invasion and metastasis are the most significant and intrinsic biological characteristics of cancers, also which are main factors of malignant tumor causing treatment failure and death. Recent studies have...Objective: Invasion and metastasis are the most significant and intrinsic biological characteristics of cancers, also which are main factors of malignant tumor causing treatment failure and death. Recent studies have found that Fra-1 plays an important role on cell migration, invasion, and maintaining malignant phenotype of transformed cells. But there are few stud- ies about the expression and location of Fra-1 in breast tissues and cells being reported .This study just aims to discuss the expression and location of transcription factor Fra-1 in benign and malignant human breast tissues. Methods: The expression of Fra-1 was investigated by immunohistochemistry in neoplastic breast diseases ranging from benign fibroadenoma to very aggressive undifferentiated carcinoma. The correlations of Fra-1 expression with other indicators of breast carcinoma prog- nosis (ER, PR and ErbB2 receptors) were analyzed. Results: All neoplastic breast tissues, either benign or malignant breast tissues, were nuclear immunoreactive for Fra-l-recognizing antibody. In 85% of benign tumors (17/20), the immunoreactive for Fra-l-recognizing antibody as exclusively restricted to the nuclei. In three cases (3/20, 15%), focal unequivocal cytoplas- mic staining was also exhibited. Strong positive nuclear staining for Fra-1 was easily seen in all types of breast carcinomas. However the nucleaflcytoplasmic concomitant immunoreactivity was observed in all types of breast carcinomas. A clear shift in Fra-1 immunoreactivity, from an exclusively nuclear to a simultaneous nuclear and cytoplasmic localization was noticed in 90.2% (37/41) of breast carcinomas. No inverse relationship between Fra-1 and ER and PR protein levels was noticed in malignant tumors. The relative expression level of Fra-1 was not correlated with the expression of ErbB2. Conclusion: The overall expression, pattern and intensity of Fra-1 proteins were correlated with breast oncogenesis. Overexpression of Fra-1, leading to a persistent high cytoplasmic accumulation, may play a role in the process of breast carcinogenesis.展开更多
基金This work was supported by funds of Natural Science of Scientific Committee and Educational Committee of AN-HUI Province respectively, and Hi-tech Research and Development Program ("863" Program).
文摘The c-erbB-2 proto-oncogene encodes a 185kDa protein p!85, which belongs to epidermal growth factor receptor family. Amplification of this gene has been shown to correlate with poor clinical prognosis for certain cancer patients. The monoclonal antibody A21 which directed against p185 specifically inhibits proliferation of tumor cells overexpressing p185, hence allows it to be a candidate for targeted therapy. In order to overcome several drawbacks of murine MAb, we cloned its VH and VL genes and constructed the single-chain Fv (scFv) through a peptide linker. The recombinant scFvA21 was expressed in Escherichia coli and purified by the affinity column. Subsequently it was characterized by ELISA, Western blot, cell immunohistochemistry and FACS. All these assays showed the binding activity to extracellular domain (ECD) of p!85. Based on those properties of scFvA21, we further constructed the scFv-Fc fusion molecule with a homodimer form and the recombinant product was expressed in mammalian cells. In a series of subsequent analysis this fusion protein showed identical antigen binding site and activity with the parent antibody. These anti-p185 engineered antibodies have promised to be further modified as a tumor targeting drugs, with a view of application in the diagnosis and treatment of human breast cancer.
文摘We have developed and tested chimeric T-cell receptors (TCR) specific for p185HER2. In these experiments, retroviral vectors expressing the N29γ or N29ζ receptors were constructed in pRET6. Amphotropic viral producer cells were established in the GALV-based PG13 packaging cell line. Ficoll purified human peripheral blood lymphocytes (PBL) were virally transduced using an optimized protocol incorporating activation with immobilized anti-CD3/anti-CD28 monoclonal anti- bodies, followed by viral infection in the presence of fibronectin fragment CH296. Transduced cells were co-cultured with human tumor cell lines that overexpress (SK-OV-3) or underexpress (MCF7) p185HER2 to assay for antigen specific im- mune responses. Both CM+ and CD8+ T-cells transduced with the N29γ or N29ζ chTCR demonstrated HER2-specific anti- gen responses, as determined by release of Th1 like cytokines, and cellular cytotoxicity assays. Our results support the fea- sibility of adoptive immunotherapy with genetically modified T-cells expressing a chTCR specific for p185HER2.
文摘Objective: Invasion and metastasis are the most significant and intrinsic biological characteristics of cancers, also which are main factors of malignant tumor causing treatment failure and death. Recent studies have found that Fra-1 plays an important role on cell migration, invasion, and maintaining malignant phenotype of transformed cells. But there are few stud- ies about the expression and location of Fra-1 in breast tissues and cells being reported .This study just aims to discuss the expression and location of transcription factor Fra-1 in benign and malignant human breast tissues. Methods: The expression of Fra-1 was investigated by immunohistochemistry in neoplastic breast diseases ranging from benign fibroadenoma to very aggressive undifferentiated carcinoma. The correlations of Fra-1 expression with other indicators of breast carcinoma prog- nosis (ER, PR and ErbB2 receptors) were analyzed. Results: All neoplastic breast tissues, either benign or malignant breast tissues, were nuclear immunoreactive for Fra-l-recognizing antibody. In 85% of benign tumors (17/20), the immunoreactive for Fra-l-recognizing antibody as exclusively restricted to the nuclei. In three cases (3/20, 15%), focal unequivocal cytoplas- mic staining was also exhibited. Strong positive nuclear staining for Fra-1 was easily seen in all types of breast carcinomas. However the nucleaflcytoplasmic concomitant immunoreactivity was observed in all types of breast carcinomas. A clear shift in Fra-1 immunoreactivity, from an exclusively nuclear to a simultaneous nuclear and cytoplasmic localization was noticed in 90.2% (37/41) of breast carcinomas. No inverse relationship between Fra-1 and ER and PR protein levels was noticed in malignant tumors. The relative expression level of Fra-1 was not correlated with the expression of ErbB2. Conclusion: The overall expression, pattern and intensity of Fra-1 proteins were correlated with breast oncogenesis. Overexpression of Fra-1, leading to a persistent high cytoplasmic accumulation, may play a role in the process of breast carcinogenesis.