Synthesis of Ag/BiOBr/CeO2 composites with enhanced photocatalytic degradation for sulfisoxazole.

A novel Ag/BiOBr/CeO2 composite was successfully prepared for the first time, which had excellent performance in degrading sulfisoxazole (SSX) under visible light irradiation. The as-prepared samples were characterized by SEM, XRD, UV-vis DRS and BET et al. The composite of 10% Ag/BiOBr/CeO2 showed the best photocatalytic activity and more than 99.5% SSX can be removed within 20 min. It exhibited the highest k value of 0.2428 min-1, which was about 39.7 times higher than pure BiOBr (6.11 × 10-3 min-1) and 22.1 times higher than BiOBr/CeO2 (1.09 × 10-2 min-1), respectively. The addition of Ag significantly improved the absorption rate of visible light and the separation rate of photogenerated electron-hole pairs. The initial pH and dosage of samples could have an influence on the photocatalytic activity. The radical trapping experiments proved that ·O2- and h+ were the main active species involved in photocatalytic degradation. Finally, the synthesized catalyst maintained excellent photocatalytic activity after 5 repeated cycles, which indicated the extraordinary stability and recyclability of Ag/BiOBr/CeO2.

The Detection of Plasma Soluble Podoplanin of Patients with Breast Cancer and Its Clinical Signification.

BACKGROUND: Podoplanin (PDPN) is a type-1 membrane sialoglycoprotein that is expressed in many cancer tumors including breast cancer; nonetheless, its roles in tumor occurrence, development, and metastasis are unclear. In this study, we aimed to investigate the clinical significance of plasma soluble PDPN (sPDPN) levels in patients with breast cancer and its significance in the diagnosis and metastasis. MATERIALS AND METHODS: Blood samples from healthy controls (CTL), patients with fibroadenomas of breast (FOB), and breast cancer (pathological type: invasive ductal carcinoma, IDC) were collected. sPDPN levels in the plasma of CTL and patients with FOB and IDC were measured by the ELISA. RESULTS: The plasma sPDPN levels in IDC patients (159 cases, 22.59±3.70 ng/mL) were higher than those in FOB patients (50 cases, 8.29±1.09 ng/mL; P<0.05) and CTL (100 cases, 1.21±0.12 ng/mL; P<0.0001). The sPDPN levels in patients at stage III and stage IV (30.08±4.66 ng/mL) were higher than in patients at stage I and stage II (11.84±1.12 ng/mL; P=0.005). The sPDPN levels in patients with high-moderate and moderate differentiation (17.50±3.02 ng/mL) were lower than those in patients with moderately low and low differentiation (35.73±4.26 ng/mL; P=0.026). The sPDPN levels in patients with metastasis (30.60±4.27 ng/mL) were much higher than those in patients without metastasis (13.02±1.30 ng/mL; P=0.017). CONCLUSION: Plasma sPDPN may be used as a new marker for the determination of the clinical stage, differentiation degree, and metastasis status of breast cancer.

Blocking podoplanin suppresses growth and pulmonary metastasis of human malignant melanoma.

BACKGROUND: Podoplanin (PDPN), a transmembrane O-glycoprotein, is up-regulated in many tumors and is involved in tumor metastasis and malignant progression. In previous studies, we generated a functional blocking monoclonal antibody (mAb, SZ168) against the extracellular domain of human PDPN. This study is aimed to investigate whether blocking PDPN by SZ168 inhibits tumor growth and metastasis. METHODS: Malignant melanoma xenograft model by inoculating subcutaneously human malignant melanoma cell line C8161 into the back of BALB/c nude mice was used. Endogenous PDPN expression in C8161 cells and nasopharyngeal cancer cell line CNE-2 was detected using western blot and flow cytometry. RESULTS: SZ168 significantly inhibited C8161 or CNE-2 cell-induced platelet aggregation in a dose-dependent manner with a maximal inhibition of 73.9 ± 3.0% in C8161 cells or 77.1 ± 2.7% in CNE-2 cells. Moreover, SZ168 inhibited the growth and pulmonary metastasis of C8161cells in vivo. The number of lung metastatic foci in the SZ168-treated group was significantly decreased compared with that in the control mouse IgG group (1.61 ± 0.44 vs.3.83 ± 0.60, P < 0.01). Subcutaneous tumor volume, weight, and incidence were also significantly reduced in the SZ168-treated group compared to the control group (P < 0.05). Additionally, SZ168 recognized PDPN in immunohistochemical analyses of tumor tissue sections. CONCLUSIONS: SZ168 blocks growth and pulmonary metastasis of human malignant melanoma by inhibiting the interaction between tumor PDPN and platelet CLEC-2 and therefore is a promising antibody for therapeutic development against malignant melanoma.

MicroRNA-196a/-196b regulate the progression of hepatocellular carcinoma through modulating the JAK/STAT pathway via targeting SOCS2.

microRNAs (miRNAs) play essential roles in progression of hepatocellular carcinoma (HCC). However, the roles of miR-196a and miR-196b as well as mechanism in HCC progression remain poorly understood. The expressions of miR-196a, miR-196b and suppressor of cytokine signaling 2 (SOCS2) were measured in HCC tissues and cells by quantitative real-time polymerase chain reaction or immunohistochemistry. HCC progression was investigated by cell proliferation, glycolysis, cycle, clones, apoptosis, and necrosis. The interaction between SOCS2 and miR-196a or miR-196b was explored by luciferase activity and RNA immunoprecipitation analyses. The expressions of proteins in Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway were measured by western blot. A xenograft model was established to investigate the roles of miR-196a or miR-196b in vivo. We found that miR-196a and miR-196b were highly expressed in HCC tissues and cells. High expression of miR-196a or miR-196b was correlated with tumor size, tumor-node-metastasis stage, lymph node metastasis, albumin-bilirubin grade and poor 5-year survival. Knockdown of miR-196a or miR-196b suppressed cell proliferation, glycolysis, cell cycle process, colony formation but induced apoptosis or necrosis in HCC cells. SOCS2 was targeted by miR-196a and miR-196b and its interference ablated abrogation of miR-196a or miR-196b-mediated inhibitory effect on HCC progression. SOCS2 was negatively associated with activation of the JAK/STAT pathway. Besides, knockdown of miR-196a or miR-196b limited xenograft tumor growth by blocking the JAK/STAT pathway. We concluded that downregulation of miR-196a or miR-196b inhibited HCC progression through regulating the JAK/STAT pathway via targeting SOCS2, providing novel targets for prognosis and therapeutics of HCC.

Extracellular vesicles secreted by hypoxia pre-challenged mesenchymal stem cells promote non-small cell lung cancer cell growth and mobility as well as macrophage M2 polarization via miR-21-5p delivery.

OBJECTIVE: To investigate the lung cancer-promoting mechanism of mesenchymal stem cell-secreted extracellular vesicles (MSC-EV). METHODS: EV were isolated from culture media of human bone marrow-derived MSCs that were pre-challenged with or without hypoxia (referred to as H-EV and N-EV, respectively). After treatment with N-EV or H-EV, A549 and H23 cell proliferation, apoptosis, trans-well invasion and epithelial-to-mesenchymal transition (EMT) were examined. Polarization of human primary monocytes-derived macrophages with or without N-EV or H-EV induction were analyzed by flow cytometry and ELISA. PTEN, PDCD4 or RECK gene was overexpressed in A549 cells, while miR-21-5p was knocked down in MSCs, A549 or H23 lung cancer cells or primary monocytes by miR-21-5p inhibitor transfection. Protein level of PTEN, PDCD4, RECK, AKT or STAT3 as well as phosphorylation level of AKT or STAT3 protein were assayed by western blot. Tumorigenicity of A549 and H23 cells with or without MSC-EV co-injection was assayed on immunocompromised mice. The xenograft tumor were examined for cell proliferation, angiogenesis, apoptosis and intra-tumoral M1/M2 macrophage polarization. RESULTS: Comparing to N-EV, H-EV treatment significantly increased A549 and H23 cell proliferation, survival, invasiveness and EMT as well as macrophage M2 polarization. MiR-21-5p knocked down significantly abrogated the cancer-promoting and macrophage M2 polarizing effects of H-EV treatment. H-EV treatment downregulated PTEN, PDCD4 and RECK gene expression largely through miR-21-5p. Overexpressing PTEN, PDCD4 and RECK in A549 cells significantly reduced the miR-21-5p-mediated anti-apoptotic and pro-metastatic effect of H-EV, while overexpressing PTEN in monocytes significantly reduced macrophage M2 polarization after induction with the presence of H-EV. H-EV co-injection significantly increased tumor growth, cancer cell proliferation, intra-tumoral angiogenesis and M2 polarization of macrophages in vivo partially through miR-21-5p. CONCLUSIONS: Increased miR-21-5p delivery by MSC-EV after hypoxia pre-challenge can promote lung cancer development by reducing apoptosis and promoting macrophage M2 polarization.

Plasma soluble podoplanin is a novel marker for the diagnosis of tumor occurrence and metastasis.

Podoplanin (PDPN) is expressed on many tumors and is involved in tumor metastasis. The objective of the present study was to develop an ELISA for determining soluble PDPN (sPDPN) levels as a potential novel tumor marker in plasma of patients with cancers for detection of tumor occurrence and metastasis. Mouse monoclonal antibodies (mAb) against human PDPN were developed and characterized. Two anti-PDPN mAb, SZ-163 and SZ-168, were used in a sandwich ELISA to detect plasma sPDPN in patients with cancers and in normal individuals. The levels of sPDPN were detected in patients with adenocarcinoma (87 cases, 31.09 ± 5.48 ng/ml), squamous cell carcinoma (86 cases, 6.91 ± 0.59 ng/ml), lung cancer (45 cases, 26.10 ± 7.62 ng/ml), gastric cancer (38 cases, 23.71 ± 6.90 ng/ml) and rectal cancer (27 cases, 32.98 ± 9.88 ng/ml), which were significantly higher than those in normal individuals (99 cases, 1.31 ± 0.13 ng/ml) (P < .0001). Moreover, the sPDPN levels in patients with metastatic cancers were higher (192 cases, 30.35 ± 3.63 ng/ml) than those in non-metastatic cancer patients (92 cases, 6.28 ± 0.77 ng/ml) (P < .0001). The post-treatment sPDPN levels of cancer patients (n = 156) (4.47 ± 0.35 ng/ml) were significantly lower compared with those seen pre-treatment (n = 128) (43.74 ± 4.97 ng/ml) (P < .0001). These results showed that an ELISA method was successfully established for quantitation of plasma sPDPN and plasma sPDPN levels correlate significantly with tumor occurrence and metastasis.

[Stable expression of recombinant human podoplanin in Chinese hamster ovary (CHO) cells].

OBJECTIVE: To construct podoplanin (PDPN) eukaryotic expression plasmid PDPN-pEGFP-N1, establish Chinese hamster ovary (CHO) cell line stably expressing recombinant human PDPN and investigate its biological activity. METHODS: PDPN cDNA was cloned from HEK293 cells by reverse transcription PCR and recombinant DNA technology and inserted into plasmid pEGFP-N1 labeled by enhanced green fluorescent protein (EGFP). The recombinant vector was identified by PCR, restriction enzyme digestion and DNA sequencing, and then transfected into CHO cells. Recombinant PDPN-EGFP was observed by fluorescent microscopy and CHO cell line with the high expression of PDPN-EGFP was selected by flow cytometry. Recombinant PDPN was detected by Western blotting and the biological activity of the cell line was determined by platelet aggregation assay. RESULTS: DNA sequencing and restriction enzyme digestion proved that the gene of PDPN was inserted successfully into pEGFP-N1 plasmid. After stable transfection of the recombinant plasmid into CHO cells, CHO with EGFP could be seen under a fluorescent microscope. The CHO cell line with the high expression of recombinant PDPN-EGFP was obtained after sorting by flow cytometry. Western blotting showed that the recombinant PDPN was expressed on the cell surface. The over-expressing PDPN-EGFP CHO cells were able to induce human platelet aggregation. CONCLUSION: The CHO cell line with the stable and high expression of recombinant PDPN-EGFP has been constructed successfully, and it could induce platelet aggregation.