[Effects of Soluble CD40 Ligand on Non-Hodgkin Lymphoma Cells and Its Relative Mechanism].

OBJECTIVE: To explore the effect of soluble CD40 ligand (sCD40L) on the proliferation, apoptosis, and cell cycle of human non-Hodgkin lymphoma (NHL) cells, and analyze its possible mechanism. METHODS: NHL CA46 cell and Raji cell were treated with different concentrations of sCD40L for 48 h, CCK-8 was used to detect the effect of sCD40L on cell proliferation in vitro, flow cytometry on apoptosis and cycle of NHL cells, and Western blot on the expression of PTEN, BCL-2, and BAX in NHL cells. RESULTS: Compared with the control group, 4 and 8 µg/ml sCD40L could significantly inhibit the proliferation of lymphoma Raji cell and CA46 cell (P<0.05). The test results of flow cytometry showed that 4 µg/ml sCD40L could significantly promote the apoptosis of CA46 and Raji cells, and significantly inhibit the S phase proportions (P<0.05). Western blot results showed that sCD40L could promote the expression of PTEN and BAX, while inhibit the expression of BCL-2 (P<0.05). CONCLUSION: sCD40L can promote the apoptosis and inhibit the proliferation of NHL cells through the PTEN signaling pathway.

[Construction and Identification of Acute Myeloid Leukemia NOD/SCID Mouse Model by Tail Vein Injection of THP-1 Cells].

OBJECTIVE: To construct NOD/SCID mouse leukemia model by using THP-1 cells. METHODS: Eighteen female NOD/SCID mice aged 3 to 4 weeks were randomly divided into control group, model group A and model group B (6 in each group). Before inoculation, each mouse was intraperitoneally injected with cyclophosphamide 2 mg/(kg·d) for 2 d, and the mice in model groups were inoculated with cells within 24 h after pretreatment. The mice in model group were inoculated with THP-1 cell suspension in logarithmic growth phase by 1×107 cells/group (group A) and 5×106 cells/group (group B), the mice in the control group were injected with the same amount of normal saline in the tail vein. The general situation was observed, blood routine test and peripheral blood leukocyte classification were performed at 7, 14, 21, 28 d of inoculation before the pre-treatment, and at the time sacrifice. Before dying, tissue of mice were collected and histological examination was performed. RESULTS: Pilereation, droopiness and hypkinesia could be observed from d 7 and d 10 of inoculation cells in model group. Compared with the control group, the body weight of the mice in model group A and B decreased significantly after 21 days of inoculation (P<0.01), and the white blood cell counts increased significantly after 28 days of modeling (P<0.01). Among them, the above-mentioned presentation in inoculation of 1×107 group A was the most significant. Histopathological sections showed diffuse infiltration of leukemia cells in the spleen of the model group. The immunohistochemistry results indicated that the leukemia cells were positive for anti-human CD13, which confirmed the successful establishment of the model. CONCLUSION: After pretreatment with intraperitoneal injection of CTX in NOD/SCID mice, the injection of 1×107 or 5×106 THP-1 cells in tail vein of each mouse can successfully construct an acute myeloid leukemia animal model. The tumor formation is more much faster by injection of high concentration THP-1 cells.

Cetuximab enhances the efficiency of irinotecan through simultaneously inhibiting the MAPK signaling and ABCG2 in colorectal cancer cells.

BACKGROUND: The present study sought to investigate the combined effects of cetuximab and irinotecan on colorectal cancer cells as well as the mechanisms underlying their anti-cancer effects. MATERIAL AND METHODS: High performance liquid chromatography, Hoechst staining assay, and western blotting analysis were used to detect intracellular drug concentrations, cell apoptosis, and protein expression in the presence of cetuximab, irinotecan, and the combination of both. RESULTS: Cetuximab was found to increase intracellular concentrations of irinotecan as well as cytotoxicity by inhibiting the epidermal growth factor receptor and, by extension, the downstream RAS-RAF-MEK-ERK signaling pathway. Cetuximab therefore induced apoptosis and improved the effect of irinotecan in colorectal cancer cells. It was also shown that cetuximab inhibited the drug efflux activity of ABCG2. In combination with irinotecan, cetuximab can both significantly induce cell apoptosis by inhibiting the RAS-RAF-MEK-ERK signaling pathway and improve the effects of irinotecan by decreasing drug efflux through the inhibition of ABCG2. CONCLUSION: These features contribute to its anti-cancer potential.

Regulatory effect of Act1 on the BAFF pathway in B-cell malignancy.

The aim of the present study was to ascertain whether nuclear factor (NF)-κB Activator 1 (Act1) was involved in B cell-activating factor (BAFF) regulation in B-cell malignancy. The human B-cell malignancy cell lines Raji, Daudi and BALL-1 were cultured and the expression of BAFF receptor (BAFF-R) mRNA and protein was analyzed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting, respectively. NF-κB signaling was also assessed using western blotting. Act1 silencing was performed using Act1 small interfering RNA. BAFF-R levels were assessed using flow cytometry. It was demonstrated that BAFF-R was upregulated in all three cell lines and RT-qPCR, and western blotting confirmed these results. Act1 overexpression was demonstrated to induce BAFF-R upregulation, whereas Act1 knockdown resulted in BAFF-R downregulation. Furthermore, the NF-κB pathway was activated by Act1 overexpression and inhibited following Act1 knockdown. The results of the present study demonstrated that Act1 can regulate BAFF via targeting NF-κB signaling, which suggests that Act1 may be a promising therapeutic target for the treatment of B-cell malignancy.

H19 contributes to poor clinical features in NSCLC patients and leads to enhanced invasion in A549 cells through regulating miRNA-203-mediated epithelial-mesenchymal transition.

Recent studies have demonstrated that the overexpression of H19 may contribute towards development of tumorigenesis in various types of cancer. To investigate the role of H19 in the development of non-small cell lung cancer (NSCLC), 76 NSCLC tissues samples and their adjacent normal tissue samples were collected. Expression level of H19, and its association with clinicopathological features and overall survival was analyzed. It was found that compared with normal adjacent tissues, H19 expression was elevated in NSCLC tissues along with a decreased miR-203 expression level. It was also found that patients who were in advanced clinical stages had a higher H19 and a lower miR-203 expression compared to normal tissues. The overall survival time of patients with higher H19 expression was shorter compared with the lower H19 expression group. Upregulation of A549 enhanced cell proliferation and promoted invasion. Overexpression of H19 stimulated the epithelial-mesenchymal transition (EMT) process in lung cancer cells and demonstrated typical morphological characteristics of EMT. The level of mesenchymal marker protein, such as Vimentin and SNAI1 increased; while CDH1 protein level decreased. Also, H19 negatively regulated miR-203. Inhibition of H19 attenuated miR-203 induced EMT process. Upregulation of H19 contributes to poor clinical features in patients with NSCLC, induces occurrence of EMT, promotes proliferation and stimulates cell invasion in NSCLC cell line through regulating miRNA-203 mediated EMT.