Experimental study of nasopharyngeal carcinoma radionuclide imaging and therapy using transferred human sodium/iodide symporter gene

Downregulation of B7-H4 suppresses tumor progression of hepatocellular carcinoma

B7-H4, as a member of the B7 superfamily, was overexpressed in various types of cancers. However, the effects of B7-H4 on the aggressiveness of HCC and the underlying mechanisms have not yet been fully explored. For this purpose, B7-H4 expression was detected by Flow cytometry and Western blotting, it was highly expressed in several HCC cell lines but not in normal LO2 cell line. Knockdown B7-H4 expression induced HCC cells apoptosis by flow cytometry and colony formation assays and increased several apoptosis-related proteins, including survivin, cleaved caspase-3, cleaved caspase-7, and Bax, while the pro-growth protein survivin was reduced. Then the proliferation and cell cycle were suppressed after treated by siB7-H4. Moreover, the level of B7-H4 was significantly correlated with cell migration. In vivo, intra-tumor injection of siRNA targeting B7-H4 can significantly inhibited the growth of HepG2 cells in nude mice. Finally, regions of interest were manually traced on T1WI, T2WI, DWI and ADC of MR images. ADC values were increased in HCC xenografts after B7-H4 siRNA treatment. These data indicated that downregulation of B7-H4 suppressed the proliferation and migration and promoted apoptosis in vitro and in vivo. Blocking the B7-H4 channel might be a potential therapeutic strategy for HCC.

In vitro study on human umbilical cord mesenchymal stem cells transfected with lentivirus-mediated hNIS-EGFP dual reporter gene and co-labeled with superparamagnetic iron oxide

The aim of the present study was to establish a stem cell line for multi-mode imaging (in vivo fluorescence imaging, magnetic resonance imaging and ^99mTc single-photon emission computed tomography) and to study the biological activity, stemness, proliferative activity and differentiation ability of superparamagnetic iron oxide (SPIO), human sodium/iodide symporter (hNIS) and enhanced green fluorescent protein (EGFP) co-labeled human umbilical cord mesenchymal stem cells (hUCMSCs). The EGFP reporter gene was selected to indirectly reflect the expression of target gene hNIS, and hUCMSCs were re-transfected with the successfully constructed recombinant plasmid pCMV-NIS-EF1-GFP-PGK-puro. When a stem cell line stably expressing hNIS and EGFP was obtained, the cells were incubated with 30 µg/ml SPIO to obtain hNIS, EGFP and SPIO co-labeled stem cells. The protein expressions of hNIS and EGFP were identified using western blot analysis, and the protein function of hNIS was identified by ¹²⁵I influx and ¹²⁵I efflux experiments. hNIS-EGFP-hUCMSCs were labeled with SPIO under the mediation of poly-L-lysine, and SPIO, hNIS and EGFP co-labeled hUCMSCs were established successfully. Staining with Prussian blue confirmed that 98% of cells were successfully labeled with SPIO. Western blotting results demonstrated positive hNIS and EGFP protein expression levels, and ¹²⁵I influx and ¹²⁵I efflux experiments confirmed that the protein function of hUCMSCs after expressing hNIS was normal. The uptake of ¹²⁵I was higher in cell lines hNIS-EGFP-hUCMSCs than in control hUCMSCs (fold change: 16.43±2.30 times; P<0.05). The stemness of hNIS-EGFP-hUCMSCs was found to be slightly decreased but not statistically significant; the overall characteristics of stem cells remained unchanged. The assessments of adipogenic and osteogenic differentiation suggest that hNIS-EGFP-hUCMSCs have no significantly different characteristics compared with primary hUCMSCs.

PTPN12 Affects Nasopharyngeal Carcinoma Cell Proliferation and Migration Through Regulating EGFR

OBJECTIVE

Nasopharyngeal carcinoma (NPC) shows the leading morbidity in otorhinolaryngological malignant tumor. It is a common malignancy in China with obvious reginal distribution. NPC is a polygenic disease that is affected by numerous factors. Protein tyrosine phosphatase nonreceptor type 12 (PTPN12) regulates multiple tumor proliferation and development, including breast cancer and colon cancer. However, the role of PTPN12 in NPC occurrence and development has not been elucidated.

PATIENTS AND METHODS

NPC cell line CNE2 was cultured in vitro and divided into three groups, including control, empty plasmid, and PTPN12 groups. PTPN12 mRNA and protein expressions were tested by real-time polymerase chain reaction and Western blot. CNE2 cell proliferation was detected by MTT assay. Cell migration was determined by wound healing assay. Cell apoptosis was evaluated by caspase 3 activity detection. Epidermal growth factor receptor (EGFR) expression was assessed by Western blot.

RESULTS

PTPN12 plasmid transfection increased PTPN12 mRNA and protein expressions, suppressed cell proliferation and migration, reduced EGFR level, and enhanced caspase 3 activity compared with control and empty plasmid groups (p < 0.05).

CONCLUSIONS

PTPN12 regulates NPC proliferation and migration through negative regulating EGFR. It could be treated as a molecular target for NPC diagnosis and prognosis analysis.

Effect of antisense microRNA targeting survivin on rectal cancer HRC-9698 cells and its mechanism

BACKGROUND

Rectal cancer seriously threats to human health. Traditional chemotherapy drugs might kill rectal cancer cells while easy cause side effects and clinical complications. Therefore, it is necessary to explore possible new methods for rectal cancer treatment. Survivin is an important tumor-specific protein. Previous researches showed it may be closely related to nasopharyngeal carcinoma. Its role in rectal cancer remains unclear.

METHODS

Cultivate human rectal cancer HRC-9698 cells. Antisense microRNA targeting survivin and control miRNA were constructed and transfected to HRC-9698 cells. MTT assay was applied to detect cell growth. Flow cytometry was used to test cell apoptosis. Western blot was performed to detect Osteopontin expression level. Colony formation and transwell assay were used to test cell clone formation and invasion abilities.

RESULTS

Antisense microRNA targeting survivin can inhibit HRC-9698 cell proliferation and induce its apoptosis. Antisense microRNA targeting survivin decreased osteopontin expression level. Overexpressed osteopontin inhibited antisense microRNA targeting survivin induced cell apoptosis. Antisense microRNA targeting survivin suppressed HRC-9698 cells' colony formation and invasion abilities.

CONCLUSION

Antisense microRNA targeting survivin induced osteopontin participated HRC-9698 cell apoptosis. Antisense microRNA targeting survivin inhibited HRC-9698 cell colony formation and invasive abilities, indicating that survivin may play its anti-tumor effect through inducing cell apoptosis and inhibiting cell metastasis and invasion.