Synergistic effects of autophagy inhibitors combined with cisplatin against cisplatin-resistant nasopharyngeal cancer cells.

This study explored the synergistic effects of autophagy inhibitors combined with cisplatin against cisplatin-resistant nasopharyngeal cancer cells by treating HNE-1 and cisplatin (diamminedichloroplatinum; DDP)-resistant HNE1/DDP nasopharyngeal cancer cell lines with DDP, autophagy inhibitors, or a combination of autophagy inhibitors and DDP. Cell viability was determined via MTT (colorimetric) and colony-forming assays, and the rate of apoptosis was determined using propidium iodide (PI) and annexin V double-staining. The expressions of proteins were determined by Western blotting. For our in-vivo studies, a murine xenograft model was established to evaluate the anti-tumor effects of the combination of autophagy inhibitor and DDP. The results showed that treatment with DDP increased the expressions of ATP-binding cassette sub-family B member 1 (ABCB1), ATP Binding Cassette Subfamily C Member 1 (ABCC1), and P-glycoprotein 1 (P-gp) in the HNE1/DDP cell lines. Treatment with chloroquine decreased the expression levels of ABCB1, ABCC1, and P-gp, and increased the formation of LC3-II and the expression levels of p62 in the HNE1/DDP cells. Additionally, the combination of autophagy inhibitors and DDP produced a synergistic effect on DDP-induced cell death and apoptosis. Furthermore, the combination of the autophagy inhibitor and DDP showed significant anti-tumor effects in the xenograft mouse model. In summary, autophagy inhibitors show synergistic anti-tumor effects with DDP in vitro against DDP-resistant nasopharyngeal cancer cells and in vivo in our xenograft murine model.

MicroRNA-139-5p affects cisplatin sensitivity in human nasopharyngeal carcinoma cells by regulating the epithelial-to-mesenchymal transition.

Nasopharyngeal carcinoma (NPC) is a head and neck cancer associated with poor prognosis. Many studies have shown that the epithelial-to-mesenchymal transition (EMT) is important in cancer progression, metastasis, and chemotherapy resistance and that microRNAs (miRNAs) play a key role in chemotherapy resistance associated with EMT. The miRNA miR-139-5p is downregulated in many human cancers and is closely related to tumor progression. The aim of this study was to investigate the ability of miR-139-5p to influence the cisplatin resistance, apoptosis, invasion and migration in NPC cells through the regulation of the EMT. We investigated these processes in parental HNE1 and cisplatin-resistant HNE1/DDP cells transfected with miR-139-5p inhibitors and mimics, respectively. Our results suggest that the upregulation of miR-139-5p expression inhibits proliferation, invasion, migration and EMT in human NPC cells. In addition, we found that miR-139-5p expression levels and DDP-induced apoptosis positively correlate in NPC cells. In conclusion, our results demonstrate that miR-139-5p can regulate the migration, invasion and DDP resistance in human NPC by modulating the EMT. The regulation of miR-139-5p levels might be a new approach to reverse EMT and DDP resistance and counteract metastasis and chemotherapy resistance in human NPC.

Cytokeratin 13 promotes the radio-sensitivity of nasopharyngeal carcinoma HNE1 cells by inhibiting the PI3K/AKT/mTOR pathway via PTEN / 中国肿瘤生物治疗杂志

@#[Abstract] Objective: To investigate the effect of cytokeratin 13 (CK13) on radio-sensitivity of human nasopharyngeal carcinoma HNE1 cell line and its mechanism. Methods: HNE1 cells were divided into control group, anti-CK13#a group (CK13 knockdown), anti-CK13#b group (CK13 knockdown), control+sirolimus group (100 nmol/L sirolimus treatment for 1 h), and anti-CK13#a + sirolimus group (100 nmol/L sirolimus treatment for 1 h). After irradiation treatment (200 cGy/min irradiation for 5 min), cell proliferation in each group was measured by CCK-8 assay. Cell apoptosis rate in each group was determined by Flow cytometry. Expression of PI3K/AKT/mTOR signaling pathway related PTEN gene was detected by qPCR, and WB was used to detect the expressions of PI3K/AKT/mTOR signaling pathway related proteins. Results: In the case of radiotherapy, as compared with the control group, the proliferation of HNE1 cells after CK13 knockdown was significantly enhanced (P<0.01) while the apoptosis rate was significantly reduced (P<0.01), the contents of caspase-3 and γH2AX as well as the protein lever of PTEN in cells were significantly decreased, while the expressions of p-AKT and p-S6K were significantly increased (all P<0.01). Interestingly, additional treatment with sirolimus (PI3K/AKT/mTOR signaling pathway inhibitor) could rescue the accelerated cell proliferation and decreased cell apoptosis caused by CK13 knockdown (all P<0.05). Conclusion: CK13 knockdown can enhance the activity of PI3K/AKT/mTOR signaling pathway by down-regulating PTEN, and ultimately reduce the radio-sensitivity of nasopharyngeal carcinoma HNE1 cells.

Effect of anti-human IgM antibody on biological characteristics of human nasopharyngeal carcinoma HNE-1 cell line in vitro and in vivo / 重庆医学

Objective To investigate the effect of anti-human immunoglobulin M (IgM) on proliferation,apoptosis,cell cycle and tumor formation in human nasopharyngeal carcinoma HNE-1 cell line in vitro and in vivo.Methods After treatment with anti-human IgM antibody,proliferation of HNE-1 cells was observed by cell proliferation inhibition assay,apoptosis and cell cycle of HNE-1 cells were detected by flow cytometry,and apoptotic cells were detected by TUNEL staining.Nude mouse models were constructed,and were injected intraperitoneally with anti-human IgM antibodies (once every 3 days).The growth of transplanted tumor was observed once every 4 days.After the fifth injection,the expression levels of IgM and gp96 protein in transplanted tumor were observed by immunohistochemical method (streptavidin-peroxidase conjugated method,SP).Results MTS assay showed that anti-human IgM antibody can significantly inhibit the proliferation of HNE-1 cells in concentration-and time-dependent manner (P＜0.05).Flow cytometry showed that the anti-human IgM antibody promoted a significant decrease in percentage of cells in G1 phase,a significant increase in percentage of cells in S phase,and a significant increase in apoptotic rate of HNE-1 cells (P＜0.05).TUNEL staining showed that the anti-human IgM antibody promoted apoptosis of HNE-1 cells (P＜0.01).Transplantation tumor experiment showed that anti-human IgM antibody can significantly inhibit the volume and weight of transplanted tumor (P＜0.05).The immunohistochemistry showed that the expression levels of IgM and gp96 proteins in mouse transplanted tumors after intraperitoneal injection with anti-human IgM antibodies were significantly lower than those of the control group (P＜0.05).Conclusion The anti-human IgM anti-body could effectively inhibit the proliferation of HNE-1 cells,promote apoptosis,and arrest cell cycle.Anti-human IgM antibody could also inhibit the growth of transplanted tumor in nude mouse,which might be related to inhibition of the expressions of IgM and gp96 proteins.

Reversal of Multidrug Resistance in NPC HNE-1(200) Cell Line by Oxymatrine / 中国药房

OBJECTIVE:To study the reversal mechanism of oxymatrine on multidrug resistance in the NPC HNE-1(200) cell line. METHODS: The multidrug resistant HNE-1(200) subline was derived from an HNE-1 cell line after exposure to fractionated X-irradiation. The expression of P-gp was tested by immunocytochemical method and western blot and that of mdr1 mRNA was measured by RT-PCR. RESULTS: After 24-hour treatment with oxymatrine, both the immunocytochemical method and western blot showed a decrease in the expression of P-gp. However, RT-PCR measurement showed that the expression of mdr1 mRNA of HNE-1 and HNE-1(200) was nonsignficant. CONCLUSION: Oxymatrine can reverse the multidrug resistance of NPC HNE-1(200) cell line to some degree by down-regulating the expression of P-gp. However, this medicine did no effect on the expression of mdr1 mRNA, suggesting the up-regulation of the expression of P-gp is under the control of multiple mechanism.

Effects of oxymartine on expression of P-glycoprotein in HNE-1 cell line radiation therapy / 重庆医科大学学报

Objective:To investigate the effects of oxymartine on cell growth and the changes of P-glycoprotein in HNE-1 cell line after exposed to fractionated X-irradiation.Methods:By MTT,the cell proliferation was observed both before X-irradiation and after X-irradiation conditions with the extent of vincristine,oxymartine and verapamil respectively.P-glycoprotein expression was tested by immunohistochemistory method SP.Results:(1)Vincristine,oxymartine and verapamil were capable of inhibiting cell growth on HNE-1 cell line and fractionated X-irradiated HNE-1(200)cell subline;(2)Vincristine was less inhibitory on cell growth in HNE-1(200)cell subline than HNE-1 cell line,and the difference had statistic significance;(3)P-glycoprotein expression in HNE-1 cell line was negative while HNE-1(200)cell subline positive;oxymartine with low inhibitory concentration could increase the expression of P-glycoprotein in HNE-1(200) cell subline,which is similar to that of verapamil.Conclusion:(1)Oxymartine is capable of inhibiting cell growth on HNE-1 cell line and fractionated X-irradiated HNE-1(200)cell subline;(2)HNE-I(200)cell subline is resistant to vincristine;(3)Oxymartine with low inhibitory concentration could increase the expression of P-glycoprotein in HNE-1(200)cell subline.which is similar to that of verapamil.

Effects of Trail combined with chenotherapeutics on proliferation and apoptosis of HNE-1 cell line / 重庆医科大学学报

Objective:To observe the effects of different concentrations of TRAIL and chemotherapeutic drugs(5-FU,DDP) on proliferation and apoptosis of HNE-1 cell lines ,both singlely and jointly.Methods:MTT was used to detect the inhibition rate.FCM was used to detect the apoptosis rate of cell.Results:The inhibition rate and apoptosis rate of combination use of TRAIL and 5-FU,DDP were significantly increased,compared with those of single use of TRAIL.Conclusion:The inhibition of proliferation and apoptosis of HNE-1 cell line can be induced by TRAIL,and the effects were higher by TRAIL combined with 5-FU and DDP.

Inhibitory Effect of Tea Polyphenols in Combination with Anti-tumor Drugs on Cell Proliferation of the Multiresistant HNE-1 Cell Line / 中国药房

OBJECTIVE: To study the joint action of tea polyphenols and common anti-tumor drugs(vincristine,pingyangmycin,5-Fu,cisplatin) in inhibiting cell proliferation of the multiresistant HNE-1(200) cell line in patients with nasopharyngeal carcinoma after radiographic exposure.METHODS: The low toxic dosage of tea polyphenols and 4 kinds of anti-tumor drugs were optimized by MTT method.Then the inhibition ratio of multiresistant HNE-1(200) cell line treated by tea polyphenols and anti-tumor drugs waere detected.RESULTS: The low toxic dosage of tea polyphenols was 0.50 mg?mL-1.When the anti-tumor drugs were used in combination with tea polyphenols(0.50 mg?mL-1) as compared without,the inhibition ratio on HNE-1(200) cell line was increased by 100%～300%.CONCLUSIONS: Addition of tea polyphenols to anti-tumor drugs showed remarkable inhibitory effect on cell proliferation of HNE-1(200) cell line in patients with nasopharyngeal carcinoma,suggesting the reverse effect of tea polyphenols on resistant HNE-1(200) cell line.