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In various cancers, abnormal USP9X expression is involved in tumor genesis, progression, apoptosis, and metastasis. However, the relationship between USP9X abnormal expression and cisplatin resistance in nasopharyngeal carcinoma (NPC) cells remains unclear. Using qRT-PCR and western blot, we detected the expressions of USP9X and β-catenin in NPC cells. The effects of USP9X on cell cisplatin resistance, proliferation, apoptosis, and metastasis were examined by CCK-8 assay, flow cytometry, wound-healing assay, and Transwell chamber assay. Co-IP assay, qRT-PCR, and western blot were performed to explore the detailed molecular mechanism of USP9X-β-catenin and its effect on the protein levels of MDR1, MRP2, Bcl-2, Bax, MMP2, and MMP9. We found that USP9X and β-catenin expressions in cisplatin-resistance cell lines (HNE1/DDP) were much higher than cisplatin-sensitive cell lines (HNE1) at both mRNA and protein levels. Co-IP assay demonstrated that USP9X was immunoprecipitated with β-catenin in NPC cells. Knockdown of USP9X was able to partially reverse cisplatin-resistance, increased cisplatin-induced apoptosis, and decreased the capacities of proliferation, migration, and invasion. Overexpression of USP9X can increase cisplatin resistance in NPC cells. Moreover, knockdown of USP9X expression can significantly reduce the expressions of MDR1, MRP2, Bcl-2, MMP2, and MMP9, but significantly increased the expression of Bax. These findings indicate that USP9X high expression plays a significant part in cisplatin-resistance of NPC. This study elucidated the possible mechanism of cisplatin resistance in NPC cells and may have implications for the therapeutic reversal of cisplatin resistance.

Recent studies hint that Ginsenoside is involved in cancer prevention and treatment. In this study, we investigated the effect of Ginsenoside Rh2 on drug resistance in human colorectal carcinoma (CRC) cells and its mechanism. The resistance reversion effect of Ginsenoside Rh2 in CRC cells was analyzed using CCK-8 assay. After treating with Ginsenoside Rh2, the cell cycle distribution and cellular apoptosis were analyzed by flow cytometry, cell migration was determined by transwell migration assay, the expression of drug-resistance genes and proteins were evaluated using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot, respectively. Ginsenoside Rh2 could enhance the cytotoxicity of 5-FU in drug-resistant CRC cells (LoVo/5-FU and HCT-8/5-FU). Treatment with Ginsenoside Rh2 could result in an increase of cell numbers in G0/G1 phase accompanied with a decrease in S-phase, and induced cellular apoptosis in drug-resistant CRC cells. In addition, the migration process and EMT process of drug-resistant CRC cells were suppressed by treatment of Ginsenoside Rh2. Compared to control group, expression of drug-resistance genes, such as MRP1, MDR1, LRP and GST, were negatively correlated to Ginsenoside Rh2. All these results indicated that Ginsenoside Rh2 could effectively reverse drug resistance in human colorectal carcinoma cell and its mechanism involved the prevention of cellular proliferation and migration, the promotion of cellular apoptosis and the alteration of drug-resistance genes, which suggested that Ginsenoside Rh2 may act as a promising candidate for drug resistance in human colorectal carcinoma chemotherapy.

Cryptotanshinone (CPT), is a quinoid diterpene isolated from the root of the Asian medicinal plant, Salvia miotiorrhiza bunge. Numerous researchers have found that it could work as a potent antitumor agent to inhibit tumor growth in vitro, buith there has been much less emphasis on its in vivo role against breast tumors. Using a mouse tumor model of MCF7 cells, we showed that CPT strongly inhibited MCF7 cell growth in vivo with polarization of immune reactions toward Th1-type responses, stimulation of naive CD4+ T cell proliferation, and also increased IFN-γ and perforin production of CD4+ T cells in response to tumor-activated splenocytes. Furthermore, data revealed that the cytotoxic activity of CD4+ T cells induced by CPT was markedly abrogated by concanamycin A(CMA), a perforin inhibitor, but not IFN-γ Ab. On the other hand, after depletion of CD4+ T cells or blocked perforin with CMA in a tumor-bearing model, CPT could not effectively suppress tumor growth, but this phenomenon could be reversed by injecting naive CD4+ T cells. Thus, our results suggested that CPT mainly inhibited breast tumor growth through inducing cytotoxic CD4+ T cells to secrete perforin. We further found that CPT enhanced perforin production of CD4+ T cells by up-regulating JAK2 and STAT4 phosphorylation. These findings suggest a novel potential therapeutic role for CPT in tumor therapy, and demonstrate that CPT performs its antitumor functions through cytotoxic CD4+ T cells.

To investigate the effect of magnolol on proliferation and apoptosis of HL-60 cells and its mechanism.MTT assay was used to measure the proliferation of HL-60 cells after treatment with different concentration of magnolol (5, 10, 20, 40, 80 and 160 µg/ml). The morphological changes of HL-60 cells were examined by light microscopy, and DAPI staining was performed to observe the nuclear morphology of HL-60 cells. The early cell apoptosis was detected by flow cytometry with Annexin V-FITC/PI double-staining. RT-PCR was carried out to examine the mRNA expression of BAX and BCL-2. Western blot was performed to detect the protein expression of caspase family.The magnolol inhibited HL-60 cell proliferation, and the inhibitory rate of cell proliferation increased significantly in a dose- and time- dependent manner (P0.05). HL-60 cells became small, even apoptotic bodies appeared after treatment with magnolol. In addition, nuclear condensation or fragmentation could be observed, which is the typical morphological features of apoptosis. When HL-60 cells were treated with 40 µg/ml of magnolol for 24 h, the ratio of early apoptotic cells reached to (11.7 ± 2.4) %, which was significant different from control (1.4 ± 1.1) % (P0.05). RT-PCR results showed that treatment of HL-60 cells with magnolol up-regulated the expression of BAX, whereas down-regulated the expression of BCL-2. Western blot results showed that the cleavages of caspase-3, -8 and -9 were significantly enhanced by magnolol.The magnolol can significantly inhibit the proliferation of HL-60 cells and induce the apoptosis of HL-60 cells, which may occur through up-regulation of BAX, down-regulation of BCL-2 and the activation of caspases.

Aim The dysfunction of T regulatory cells is important for the pathogenesis of systemic lupus erythematosus (SLE). Glucocorticoid-induced tumor necrosis factor receptor family-related protein (GITR) is expressed at low levels on resting responder T lymphocytes (Tresps) and is up-regulated on T regulatory cells (Tregs) and activated T cells, diminishing suppressive activity of Tregs and/or leading to resistance to suppression of Tregs by activated effector T cells. We aimed to explore whether SLE patients had an aberrant expression of GITR on Tregs and responder T cells (Tresps) and the regulation by glucocorticoids. Methods The surface GITR expression on Tregs and Tresps cells were analyzed by flow cytometry in 32 patients and 15 normal controls. Purified Tregs or Tresps were cultured with glucocorticoid. Apoptosis of the cells were determined by the staining of Annexin V. Results Systemic lupus erythematosus patients had higher levels of GITR expressed on CD4+CD25+, CD4+CD25high and CD4+CD25+CD127low/− Tregs as well as on CD4+CD25− Tresps compared to healthy controls. The expression of GITR on Tregs and Tresps were positively correlated with score of SLE disease activity index (SLEDAI). In vitro glucocorticoid induced GITR expression on purified Tresp cells, but not on Tregs, and almost all of the GITR positive cells induced by glucocorticoid encountered apoptosis. Conclusion Aberrant expression of GITR may contribute to SLE pathogenesis. Glucocorticoid may achieve its therapeutic effect partly by inducing GITR expression on Tresps rather than Tregs, which initiates the apoptosis of Tresp cells in SLE patients.

Objective: To detect the effect of arsenic trioxide or ATRA on APL cells or HL-60 cells and to investigate the mechanism of the hyperleukocytosis and detect the cross resistance between ATRA and arsenic trioxide. Methods: The number of promyelocytes or more matured granulocytes were counted by regular method, MTT test was used to measure the proliferation of HL-60 cells or APL cells, flow cytometry analysis to measure the apoptosis, NBT method to detect the differentiation of HL-60 cells or APL cells. Results: The proliferation of primary APL cells or HL-60 cells could be inhibited in vitro by either arsenic trioxide or ATRA, which could induce obvious apoptosis or obvious differentiation of primary APL cells or HL-60 cells. Inhibition of proliferation or apoptosis of ATRA resistant HL-60 cells were achieved by exposure to arsenic trioxide in vitro. On the other hand, the results of in vivo treatment showed that arsenic trioxide also induce of hyperleukocytosis. Conclusion: The results indicated that the hyperleukocytosis induced by ATRA is not contributed to the mechanism of more differentiation than apoptosis, there was not cross resistance between ATRA and arsenic trioxide.

Background Dihydroartemisinin (DHA) exhibits potent anti-malarial and anti-cancer activities. This study aimed to investigate the anti-proliferative effects of a combination of DHA and doxorubicin (DOX) on human breast cancer cells. Methods MTT assay and the combination index (CI) were used to show the anti-proliferative effects and calculate the synergism potential, respectively. Flow cytometry assay was used to detect apoptosis and the intracellular accumulation of DOX. JC-1 staining was used to determine the mitochondrial membrane potential. Western blot analysis was used to detect the protein expression of some apoptosis-related molecules. Results Asynergistic anti-proliferative effect was found, and the enhanced anti-cancer activity was observed to be accompanied by the prompt onset of apoptosis in MCF-7 cells. The combinative treatment remarkably decreased the mitochondrial membrane potential and activated caspase cascades more than the mono-treatment. Pretreatment with DHAalso did not influence the accumulation of DOX in MCF-7 cells. Conclusion This study presented a new opportunity to enhance the effectiveness of future treatment regimens of breast cancer using DOX.

AIM: To study the effects of chromic-P32 phosphate (32P colloids) interstitial administration in Pc-3 implanted pancreatic carcinoma, and investigate its anticancer mechanism. METHODS: Ninety-eight tumor bearing nude mice were killed at different time points after the injection of 32P colloids to the tumor core with observed radioactivity. The light microscopy, transmission electron microscopy (TEM) and immuno-histochemistry and flow cytometry were used to study the rates of tumor cell necrosis, proliferating cell nuclear antigen index, the micro vessel density (MVD). The changes of the biological response to the lymphatic transported 32P colloids in the inguinal lymph node (ILN) were dynamically observed, and the percentage of tumor cell apoptosis, and Apo2.7, caspase-3, Bcl-2, Bax-related gene expression were observed too. RESULTS: The half-life of effective medication is 13 d after injection of 32P colloids to the tumor stroma, in 1-6 groups, the tumor cell necrosis rates were 20%, 45%, 65%, 70%, 95% and 4%, respectively (F = 4.14-105.36, P