noscapine and Colonic-Neoplasms

Objective To investigate the effects of cadherin 17 (CDH17) on the proliferation and apoptosis of noscapine-resistant human SW480 colon cancer cells. Methods The level of CDH17 in noscapine-resistant human SW480 colon cancer cells was knocked down by small interfering RNA (siRNA), and the silence was confirmed by Western blotting and real-time quantitative PCR. Transfected SW480 cells were treated with noscapine, and then the proliferation and cell viability of SW480 cells were measured by MTT assay and plate clone formation assay, respectively; the apoptosis of SW480 cells was detected by flow cytometry combined with annexinV-FITC/PI staining; the expressions of poly-ADP-ribose polymerase (PARP) and caspase-3 were determined by Western blotting. Results Compared with NC-siRNA group and control group, the expression levels of CDH17 protein and mRNA were down-regulated in the CDH17-siRNA-transfected SW480 cell lines. After noscapine treatment, compared with NC-siRNA and control group, the colony-forming ratio and cell viability were significantly lower in CDH17-siRNA -transfected cell lines, and the expression levels of cleaved-PARP and cleaved- caspase-3 were up-regulated in CDH17-siRNA group, and the cell apoptosis rate increased. Conclusion Knock-down of CDH17 in SW480 cells can effectively inhibit cell proliferation and promote cell apoptosis as well as improve SW480 cell sensitivity to narcotine.

Topics: Apoptosis; Cadherins; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Drug Resistance, Neoplasm; Humans; Noscapine

The aim of the present study was to explore the signaling pathway of noscapine which induces apoptosis by blocking liver-intestine cadherin (CDH17) gene in colon cancer SW480 cells.. Human colon cancer SW480 cells were transfected with CDH17 interference vector and treatment with 10 µmol/L noscapine. The proliferation and apoptosis of SW480 cells were detected by MTT assay and AnnexinV-FITC/PI flow cytometry kit (BD), respectively. Cell invasion were assessed by transwell assays. Apoptosis related proteins (Cyt-c, Bax, Bcl-2 and Bcl-xL) levels were evaluated by western blot.. Compared to the noscapine group, the proliferation was decreased significantly and the apoptosis was increased significantly in SW480 cells of the siCDH17+noscapine group. Cyt-c and Bax protein levels in siCDH17+noscapine group was higher than that of the noscapine group, but Bcl-2 and Bcl-xL protein levels in siCDH17+noscapine group were lower than that of the noscapine group. Moreover, up-expression of CDH17 inhibited the efficacy of noscapine-induced apoptosis in SW480 cells.. We inferred that down-expression of extrinsic CDH17 gene can conspicuously promote apoptosis-inducing effects of noscapine on human colon cancer SW480 cells, which is a novel strategy to improve chemotherapeutic effects on colon cancer.

Topics: Apoptosis; Blotting, Western; Cadherins; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Down-Regulation; Flow Cytometry; Gene Expression Regulation, Neoplastic; Humans; Intestinal Mucosa; Intestines; Liver; Noscapine; Signal Transduction

Noscapine, a phthalide isoquinoline alkaloid derived from opium, has been widely used as a cough suppressant for decades. Noscapine has recently been shown to potentiate the anti-cancer effects of several therapies by inducing apoptosis in various malignant cells without any detectable toxicity in cells or tissues. However, the mechanism by which noscapine induces apoptosis in colon cancer cells remains unclear. The signaling pathways by which noscapine induces apoptosis were investigated in colon cancer cell lines treated with various noscapine concentrations for 72 h, and a dose-dependent inhibition of cell viability was observed. Noscapine effectively inhibited the proliferation of LoVo cells in vitro (IC(50)=75 μM). This cytotoxicity was reflected by cell cycle arrest at G(2)/M and subsequent apoptosis, as indicated by increased chromatin condensation and fragmentation, the upregulation of Bax and cytochrome c (Cyt-c), the downregulation of survivin and Bcl-2, and the activation of caspase-3 and caspase-9. Moreover, in a xenograft tumor model in mice, noscapine injection clearly inhibited tumor growth via the induction of apoptosis, which was demonstrated using a TUNEL assay. These results suggest that noscapine induces apoptosis in colon cancer cells via mitochondrial pathways. Noscapine may be a safe and effective chemotherapeutic agent for the treatment of human colon cancer.

Topics: Animals; Antineoplastic Agents; Apoptosis; bcl-2-Associated X Protein; Caspase 3; Caspase 9; Cell Cycle Checkpoints; Cell Line, Tumor; Colonic Neoplasms; Cytochromes c; Humans; Male; Mice; Mice, Inbred BALB C; Mitochondria; Noscapine; Xenograft Model Antitumor Assays

We have previously discovered the naturally occurring antitussive alkaloid noscapine as a tubulin-binding agent that attenuates microtubule dynamics and arrests mammalian cells at mitosis via activation of the c-Jun NH(2)-terminal kinase pathway. It is well established that the p53 protein plays a crucial role in the control of tumor cell response to chemotherapeutic agents and DNA-damaging agents; however, the relationship between p53-driven genes and drug sensitivity remains controversial. In this study, we compared chemosensitivity, cell cycle distribution, and apoptosis on noscapine treatment in four cell lines derived from the colorectal carcinoma HCT116 cells: p53(+/+) (p53-wt), p53(-/-) (p53-null), p21(-/-) (p21-null), and BAX(-/-) (BAX-null). Using these isogenic variants, we investigated the roles of p53, BAX, and p21 in the cellular response to treatment with noscapine. Our results show that noscapine treatment increases the expression of p53 over time in cells with wild-type p53 status. This increase in p53 is associated with an increased apoptotic BAX/Bcl-2 ratio consistent with increased sensitivity of these cells to apoptotic stimuli. Conversely, loss of p53 and p21 alleles had a counter effect on both BAX and Bcl-2 expression and the p53-null and p21-null cells were significantly resistant to the antiproliferative and apoptotic effects of noscapine. All but the p53-null cells displayed p53 protein accumulation in a time-dependent manner on noscapine treatment. Interestingly, despite increased levels of p53, p21-null cells were resistant to apoptosis, suggesting a proapoptotic role of p21 and implying that p53 is a necessary but not sufficient condition for noscapine-mediated apoptosis.

Topics: Alleles; Apoptosis; bcl-2-Associated X Protein; Cell Division; Colonic Neoplasms; Cyclin-Dependent Kinase Inhibitor p21; G2 Phase; HCT116 Cells; Humans; Noscapine; Proto-Oncogene Proteins c-bcl-2; Tumor Suppressor Protein p53