Objective： Lung cancer has emerged as a leading cause of cancer death in the world. Current therapies are ineffective, thus new approaches are needed to improve the therapeutic ratio. RNA interference （RNAi） has sh...Objective： Lung cancer has emerged as a leading cause of cancer death in the world. Current therapies are ineffective, thus new approaches are needed to improve the therapeutic ratio. RNA interference （RNAi） has shown promise in gene silencing in vitro, the potential of which in developing new methods for the therapy of non-small-cell lung cancer （NSCLC） needs to be further tested in vivo. In this study, chemically synthesized double-stranded RNA （dsRNA） targeting epidermal growth factor receptor （EGFR） was transfected into NSCLC cell line SPC-A1 cells and established the tumor burdened athymic nude mice model to investigate whether dsRNA could induce gene silencing in NSCLC cells in vivo. Methods： SPC-A1 was transfected with EGFR sequence-specific dsRNA formulated with Lipofectamine 2000. SPC-A1 cells （1 × 107/ mL） in 200 pL were injected s.c. into the left flank area of the mice to establish the tumor burdened athymic nude mice model. Calculate the tumor growth inhibition rate by measuring the diameter and the weight of the tumor. Immunohistochemistry and Westem blot were used to monitor the reduction in the production of the EGFR protein. Realtime RT-PCR was used to detect the silencing of the EGFR mRNA level. Results： It displayed that EGFR sequence specific dsRNA （dsRNA-EGFR） significantly inhibited the tumor growth in vivo. The tumor growth inhibition rate was 75.03%. The dsRNA-EGFR sequence specifically silenced EGFR with 53.6% of down-regulation of EGFR protein production and 32.3% of silencing of EGFR mRNA level. Conclusion： DsRNA-EGFR showed a blockbuster effect in downregulation of EGFR mRNA level and protein production, and inhibition of tumor growth in vivo.展开更多
OBJECTIVE To investigate whether CXCL12 and its receptor, CXCR7, play a role in lung cancer invasion and metastasis. METHODS Western blot and immunocytochemistry were used to detect CXCR7 protein expression in 8 lung ...OBJECTIVE To investigate whether CXCL12 and its receptor, CXCR7, play a role in lung cancer invasion and metastasis. METHODS Western blot and immunocytochemistry were used to detect CXCR7 protein expression in 8 lung cancer cell lines, EKVX, HOP62, HOP92, NCI-H23, NCI-H226, NCI- H322M, NCI-H446, and A549, and cell migration experiment was conducted to observe mobility of the lung cancer cells. The concentration of intracellular calcium in cytoplasm was measured under the fluorescence microscopy. RESULTS CXCR7 protein was positively expressed in the 8 lung cancer cell lines EKVX, HOP62, HOP92, NCI-H23, NCI-H226, NCI- H322M, NCI-H446, and A549. Following CXCL12 stimulation, obvious pseudopodia of lung cancer cells was observed under the microscope. The cell migration experiment showed that after incubation with CXCL12, the number of EKVX cells, which passed through the polycarbonate microporous filter membranes increased to a great extent. This phenomenon can be reversed by CXCR7-siRNA. After CXCL12 incubation, the intracellular Ca2＋ level in the EKVX cells was increased to a great extent. CONCLUSION Chemokine CXCL12 facilitates the migration of lung cancer cells by changing the concentration of intracellular Ca2＋. The CXCL12-CXCR7 axis may play an important role in lung cancer invasion and metastasis. It could be a potential target for lung cancer therapy and an effective way to prevent recurrence and metastasis of lung cancer.展开更多
基金Supported by a grant from the Natural Science Foundation of Shanghai （No. 03ZR14004）.
文摘Objective： Lung cancer has emerged as a leading cause of cancer death in the world. Current therapies are ineffective, thus new approaches are needed to improve the therapeutic ratio. RNA interference （RNAi） has shown promise in gene silencing in vitro, the potential of which in developing new methods for the therapy of non-small-cell lung cancer （NSCLC） needs to be further tested in vivo. In this study, chemically synthesized double-stranded RNA （dsRNA） targeting epidermal growth factor receptor （EGFR） was transfected into NSCLC cell line SPC-A1 cells and established the tumor burdened athymic nude mice model to investigate whether dsRNA could induce gene silencing in NSCLC cells in vivo. Methods： SPC-A1 was transfected with EGFR sequence-specific dsRNA formulated with Lipofectamine 2000. SPC-A1 cells （1 × 107/ mL） in 200 pL were injected s.c. into the left flank area of the mice to establish the tumor burdened athymic nude mice model. Calculate the tumor growth inhibition rate by measuring the diameter and the weight of the tumor. Immunohistochemistry and Westem blot were used to monitor the reduction in the production of the EGFR protein. Realtime RT-PCR was used to detect the silencing of the EGFR mRNA level. Results： It displayed that EGFR sequence specific dsRNA （dsRNA-EGFR） significantly inhibited the tumor growth in vivo. The tumor growth inhibition rate was 75.03%. The dsRNA-EGFR sequence specifically silenced EGFR with 53.6% of down-regulation of EGFR protein production and 32.3% of silencing of EGFR mRNA level. Conclusion： DsRNA-EGFR showed a blockbuster effect in downregulation of EGFR mRNA level and protein production, and inhibition of tumor growth in vivo.
文摘OBJECTIVE To investigate whether CXCL12 and its receptor, CXCR7, play a role in lung cancer invasion and metastasis. METHODS Western blot and immunocytochemistry were used to detect CXCR7 protein expression in 8 lung cancer cell lines, EKVX, HOP62, HOP92, NCI-H23, NCI-H226, NCI- H322M, NCI-H446, and A549, and cell migration experiment was conducted to observe mobility of the lung cancer cells. The concentration of intracellular calcium in cytoplasm was measured under the fluorescence microscopy. RESULTS CXCR7 protein was positively expressed in the 8 lung cancer cell lines EKVX, HOP62, HOP92, NCI-H23, NCI-H226, NCI- H322M, NCI-H446, and A549. Following CXCL12 stimulation, obvious pseudopodia of lung cancer cells was observed under the microscope. The cell migration experiment showed that after incubation with CXCL12, the number of EKVX cells, which passed through the polycarbonate microporous filter membranes increased to a great extent. This phenomenon can be reversed by CXCR7-siRNA. After CXCL12 incubation, the intracellular Ca2＋ level in the EKVX cells was increased to a great extent. CONCLUSION Chemokine CXCL12 facilitates the migration of lung cancer cells by changing the concentration of intracellular Ca2＋. The CXCL12-CXCR7 axis may play an important role in lung cancer invasion and metastasis. It could be a potential target for lung cancer therapy and an effective way to prevent recurrence and metastasis of lung cancer.
