The progress of PET/MRI in clinical management of patients with pancreatic malignant lesions.

Recently, the morbidity and mortality of pancreatic cancer have been increasing year by year. Because of its deep anatomical location and because most presented patients often suffer from abdominal pain or jaundice, it is difficult to diagnose pancreatic cancer at an early stage, leading to late clinical stage and poor prognosis. integrated positron emission tomography/magnetic resonance imaging (PET/MRI) fusion imaging not only has the characteristics of high resolution and multi-parameter imaging of MRI, but also combines the high sensitivity and the semi-quantitative characteristics of PET. In addition, the continuous development of novel MRI imaging and PET imaging biomarkers provide a unique and precise research direction for future pancreatic cancer research. This review summarizes the value of PET/MRI in the diagnosis, staging, efficacy monitoring, and prognosis evaluation of pancreatic cancer, and prognosis for developing emerging imaging agents and artificial intelligence radiomics in pancreatic cancer.

Polypeptides IGF-1C and P24 synergistically promote osteogenic differentiation of bone marrow mesenchymal stem cells in vitro through the p38 and JNK signaling pathways.

OBJECTIVES: Insulin-like growth factor-1 (IGF-1) and bone morphogenetic protein 2 (BMP-2) both promote osteogenesis of bone marrow mesenchymal stem cells (BMSCs). IGF-1C, the C domain peptide of IGF-1, and P24, a BMP-2-derived peptide, both have similar biological activities as their parent growth factors. This study aimed to investigate the effects and mechanisms of polypeptides IGF-1C and P24 on the osteogenic differentiation of BMSCs. METHODS: The optimum concentrations of IGF-IC and P24 were explored. The effects of the two polypeptides on BMSC proliferation and osteogenic differentiation were examined using a CCK-8 assay, flow cytometry, alkaline phosphatase (ALP) staining, ALP activity assay, alizarin red S staining, qPCR, and Western blotting. In addition, specific pathway inhibitors were utilized to explore whether the p38 and JNK pathways were involved in this process. RESULTS: The optimal concentration of both polypeptides was 50 µg/ml. IGF-1C and P24 synergistically promoted BMSC proliferation, increased ALP activity and calcified nodule formation, upregulated the mRNA and protein levels of Osx, Runx2, Ocn, Opn, and Col1a1, and improved the phosphorylation levels of p38 and JNK proteins. Inhibition of the pathways significantly reduced p38 and JNK activation and blocked Runx2 expression while inhibiting ALP activity and calcified nodule formation. CONCLUSIONS: These findings suggest that IGF-1C and P24 synergistically promote the osteogenesis of BMSCs through activation of the p38 and JNK signaling pathways.

Characterization of Silk Fibroin/Chitosan 3D Porous Scaffold and In Vitro Cytology.

Bone tissue engineering is a powerful tool to treat bone defects caused by trauma, infection, tumors and other factors. Both silk fibroin (SF) and chitosan (CS) are non-toxic and have good biocompatibility, but are poor biological scaffolds when used alone. In this study, the microscopic structure and related properties of SF/CS composite scaffolds with different component ratios were examined. The scaffold material most suitable for osteoblast growth was determined, and these results offer an experimental basis for the future reconstruction of bone defects. First, via freeze-drying and chemical crosslinking methods, SF/CS composites with different component ratios were prepared and their structure was characterized. Changes in the internal structure of the SF and CS mixture were observed, confirming that the mutual modification between the two components was complete and stable. The internal structure of the composite material was porous and three-dimensional with a porosity above 90%. We next studied the pore size, swelling ratio, water absorption ratio, degradation and in vitro cell proliferation. For the 40% SF-60% CS group, the pore size of the scaffold was suitable for the growth of osteoblasts, and the rate of degradation was steady. This favors the early adhesion, growth and proliferation of MG-63 cells. In addition to good biocompatibility and satisfactory cell affinity, this material promotes the secretion of extracellular matrix materials by osteoblasts. Thus, 40% SF-60% CS is a good material for bone tissue engineering.

MiR-320a acts as a prognostic factor and Inhibits metastasis of salivary adenoid cystic carcinoma by targeting ITGB3.

BACKGROUND: Salivary Adenoid cystic carcinoma (SACC) patients with local invasion and lung metastasis are often resistant to conventional therapy such as operation, chemotherapy and radiotherapy. To explore the underling mechanisms, we studied the roles of miRNA in regulating invasiveness of SACC cells. METHODS: MicroRNA profiling was done in SACC cells with microarray. MiRNA mimics or antisense oligonucleotide was transfected and invasiveness of SACC cells was evaluated by adhesion assay and transwell assay. The target gene of miRNA was identified by luciferase reporter assay and "rescue" experiment. Tumor metastasis was evaluated by BALB/c-nu mice xenografts. MiRNA and its target gene expression were identified by in-situ hybridization and immunohistochemistry respectively, in 302 patients from affiliated hospitals of Sun Yat-sen University and in 148 patients from affiliated hospitals of Central South University, and correlated to the clinicopathological status of the patients. RESULTS: MiR-320a was down-regulated in high lung metastatic ACCM and SACC-LM cells compared with the corresponding low metastatic ACC2 and SACC-83 cells, and inhibited adhesion, invasion and migration of SACC cells by targeting integrin beta 3 (ITGB3). In vivo, enforced miR-320a expression suppressed metastasis of SACC xenografts. In the two independent sets, miR-320a was downregulated in primary SACCs with metastasis compared to those without metastasis, and low expression of this miRNA predicts poor patient survival and rapid metastasis. Multivariate analysis showed that miR-320a expression was an independent indicator of lung metastasis. CONCLUSIONS: MiR-320a inhibits metastasis in SACCs by targeting ITGB3 and may serve as a therapeutic target and prognostic marker in salivary cancers.

Silencing Dicer expression enhances cellular proliferative and invasive capacities in human tongue squamous cell carcinoma.

microRNAs (miRNAs) are aberrantly expressed in cancer. An enzyme essential for miRNA processing is Dicer, whose expression is deregulated in diverse types of cancer and correlates with tumor progression. However, whether the regulation of Dicer expression affects tongue squamous cell carcinoma is unknown. In the present study, we investigated how silencing the expression of Dicer alters cell proliferation, cell cycle patterns, and cell migration and invasion in the Tca-8113 tongue squamous cell carcinoma cell line. Dicer expression levels were determined using quantitative PCR and western blot analysis in normal oral gingival epithelial cells and in two tongue squamous cell carcinoma lines, Tca-8113 and UM-1. Tca-8113 cells were transfected with Dicer siRNA or a negative control siRNA. Cell proliferation was determined using the MTT assay and the cell cycle was examined using flow cytometry. Cell migration and invasion changes were evaluated using wound-healing, adherence and Transwell assays. Dicer was expressed at lower levels in the tongue squamous cell carcinoma cell lines Tca-8113 and UM-1 compared to normal gingival epithelial cells, and less Dicer was expressed in UM-1 cells compared to Tca-8113 cells. Notably, Tca-8113 cells transfected with Dicer siRNA had significantly higher proliferative and invasive abilities than cells transfected with the negative control siRNA or non-transfected cells. Silencing Dicer may promote the progression of tongue squamous cell carcinoma. Dicer could serve a promising biomarker and a potential therapeutic target for tongue squamous cell carcinoma.

[Tyrosine kinase 2 with immunoglobulin-like and epidermal growth factor homology domains RNA interference inhibit the proliferation of human umbilical vein endothelial cells].

OBJECTIVE: The purpose of this study was to investigate the regulatory role of tyrosine kinase 2 with immunoglobulin-like and epidermal growth factor homology domains (Tie2) on apoptosis and proliferation in the endothelial cells. METHODS: RNA interference (RNAi) technique was used to silence Tie2 gene expression by transfecting an expression vector containing short hairpin RNA(shRNA) for Tie2 into human umbilical vein endothelial cells (HUVECs). Real time quantitation reverse transcriptase polymerase chain reaction (QRT-PCR) and Western blot were used to monitor Tie2 mRNA, as well as protein expression. The proliferation of HUVECs was examined by methyl thiazolyl tetrazolium (MTT), and the apoptosis was detected under microscope. HUVECs transfected with pGenesil-hk was negative control, and HUVECs transfected with nothing was empty control. RESULTS: Tie2 mRNA expression was down-regulated 24 h and 48 h after transfection, and Tie2 protein expression was significantly down-regulated at 24 h and 48 h (P< 0.05), especially 48 h after transfection. The apoptosis rate was conspicuously higher in experimental group than in negative control and empty control group after 48 h (P<0.05). The growth monitoring showed that proliferation was also markedly inhibited in experimental group (P<0.05) compared with two control groups. CONCLUSION: Down-regulated expression of Tie2 by RNAi can promotes apoptosis of HUVECs and has an anti-proliferation activity effect on them.

[Intratumor injection of recombinant attenuated salmonella carrying Mycobacterium tuberculosis heat shock protein 70 and herpes simplex virus thymidine kinase genes to suppress murine melanoma growth].

OBJECTIVE: To study the effection of suppression murine melanoma growth by Intratumor injection of recombinant attenuated salmonella carrying heat shock protein 70 and herpes simplex virus thymidine kinase genes. METHODS: Plasmids PCMV-mtHSP70-IRES-TK were electro-transferred into salmonella typhimurium SL7207 to construct recombinant salmonella typhimurium. In vivo, Recombinant bacteria were injected into the mouse melanoma and the antitumor effection was observed. The survival period was recorded and safety analysis for this vaccine in each group. RESULTS: In vivo, the mtHSP70/HSV-tk recombinant bacteria can suppress tumor growth significantly and extend survival. After recombinant Salmonella, 10(9) CFU/mL, was administered as an intratumoral injection, No diarrhea were observed. During therapy, body weight did not change markedly. CONCLUSION: Results of the animal experiment suggests intratumor injection of recombinant attenuated salmonella typhimurium containing mtHSP70 and HSV-tk genes, has targeting ability against B16 tumor cell and could significantly inhibit tumor growth .

Suppression of murine melanoma growth by a vaccine of attenuated Salmonella carrying heat shock protein 70 and Herpes simplex virus-thymidine kinase genes.

Attenuated Salmonella can invade tumor cells and acts as a eukaryotic expression vector for gene propagation. We constructed a bi-gene, eukaryotic co-expression DNA vaccine of Mycobacterium tuberculosis heat shock protein 70 (mtHSP70) and Herpes simplex virus-thymidine kinase (HSV-tk) and used attenuated Salmonella as a vector to treat murine melanoma. In vitro, recombinant Salmonella can carry plasmid stably and can invade into the cytoplasm of B16 tumor cells expressing the protein of the mtHSP70/HSV-tk gene by Western blot assay. In vivo, after the recombinant Salmonella was injected into tumors, the HSV-tk precursor drug ganciclovir (GCV) was administered to start the HSV-tk killing of tumor cells. We found that the mtHSP70/HSV-tk recombinant bacteria can raise CD8+ T lymphocytes in peripheral blood by flow cytometry and in tumor tissues by immunofluorescence detection, increase IFN­Î³ contents in tumor tissue by ELISA and significantly suppress tumor growth.

[Construction of the eukaryotic coexpression vector containing Mycobacterium tuberculosis heat shock protein 70 and green fluorescent protein].

OBJECTIVE: To construct an eukaryotic coexpression vector containing Mycobacterium tuberculosis heat shock protein 70 (mtHSP70) and enhanced green fluorescent protein (EGFP) controlled by cytomegalovirus promoter using pIRES-EGFP vector. METHODS: The mtHSP70 gene fragment was amplified by PCR from pVAX-mtHSP70-HSV2gD using specific primers. The PCR product was cloned into the vector pMD 18-T vector, and the correct clone was selected according to DNA sequence analysis. The interested mtHSP70 gene fragment was subcloned into pCMV-IRES-EGFP vector with XhoI and EcoR I digestion. The recombinant plasmid was transfected into mouse melanoma B16 cell line, and the green fluorescent cells were detected by fluorescence microscopy and mtHSP70 expression was detected by Western blotting. RESULTS: The recombinant plasmid obtained was confirmed by enzyme digestion. The transfected mouse melanoma B16 cells exhibited green fluorescence under fluorescence microscopy and expressed mtHSP70 protein as demonstrated by Western blotting. CONCLUSION: The eukaryotic coexpression vector PCMV-mtHSP70-IRES-EGFP has been established to allow further investigation of the role of mtHSP70 gene in tumor immunotherapy.

Inhibition of VEGF expression in tongue squamous cancer cells via RNA interference silencing of iNOS gene.

The purpose of this study was to investigate the regulatory role of the inducible nitric oxide synthase (iNOS) gene on vascular endothelial growth factor (VEGF) expression in oral squamous cancer cells. The RNA interference (RNAi) technique was used to silence iNOS gene expression by transfecting an expression vector containing short hairpin RNA (shRNA) for iNOS into Tca8113 tongue squamous cancer cells using cationic liposomes. Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting were used to monitor iNOS and VEGF mRNA, as well as protein expression. iNOS mRNA expression was significantly downregulated 24 and 36 h after transfection, and iNOS protein expression was significantly downregulated at 36 and 48 h (P<0.05 versus control), showing that effective silencing was achieved. VEGF mRNA was significantly decreased 24 and 36 h post-transfection, and VEGF protein expression was significantly decreased at 36 and 48 h (P<0.05). RNAi can decrease iNOS gene expression and achieve a gene silencing effect. iNOS gene silencing reduces VEGF expression levels in Tca8113 cells. Thus, there is a relationship between iNOS and VEGF expression in tongue squamous cancer cells.

Effect of using RNA interference to alter iNOS gene expression on the proliferation of tongue squamous cell carcinoma cell line Tca8113.

This study used RNA interference (RNAi) to explore the effect of NO and inducible nitric oxide synthase (iNOS) on apoptosis and proliferation in the tongue squamous carcinoma cell line Tca8113. Tca8113 cells were transfected with the plasmid pGenesil-1, which expresses iNOS short hairpin RNA (shRNA), or the negative control plasmid pSilencer-HK, and the transfected cells were compared with untransfected cells. The expression of iNOS was detected by histochemistry, and apoptosis was detected by flow cytometry. The expression of iNOS was significantly lower in the pSilencer-iNOS group than in the pSilencer-HK and empty control groups. The apoptosis rate was significantly higher in the pSilencer-iNOS group than in the pSilencer-HK and empty control groups. Growth monitoring showed that proliferation was also inhibited in cells transfected with pSilencer-iNOS. RNAi gene silencing decreased iNOS gene expression, induced apoptosis, and suppressed proliferation in Tca8113 cells.

[Influence of iNOS silencing by RNA interference on proliferation activity of Tca8113 cell].

OBJECTIVE: To investigate the apoptosis and proliferation activity of Tca8113 cells. METHODS: The vector that involves short hairpin RNA of iNOS was transfected to Tca8113 cells. The change of iNOS expression was observed using immunohistochemistry technique, the apoptosis rate examined by flow cytometry, and the proliferation Tca8113 cells examined by methyl thiazolyl tetrazolium (MTT). RESULTS: The expression of iNOS in Psilencer-iNOS group was lower than that in control groups (P < 0.01), the apoptosis rate was higher than that in control groups (P < 0.01); whereas the proliferation activity of Tca8113 cells in Psilencer-iNOS group was lower than that in control groups. CONCLUSIONS: Down expression of iNOS by RNAi can promotes apoptosis of Tca8113 cells and has an anti-proliferation activity effect.

[Study on the inhibition of vascular endothelial growth factor expression in Tca8113 cell by inducible nitric oxide synthase gene RNA interference].

OBJECTIVE: To investigate the effect of inducible nitric oxide synthase (iNOS) on vascular endothelial growth factor (VEGF) expression. METHODS: The vector containing short hairpin RNA of iNOS was transfected into Tca8113 cells using the RNA interference (RNAi) technique. The gene and protein expression of iNOS and VEGF was examined by RT-PCR and Western blot. RESULTS: The expression of iNOS, VEGF gene in Tca8113 cells was significantly different between the experimental and control groups 24 h and 48 h after transfection (P < 0.05). The protein expression of iNOS was different between the two groups 36 h and 48 h after transfection, and of VEGF was also different between the two groups 48 h after transfection (P < 0.05). CONCLUSIONS: The expression of VEGF could be down-regulated by silencing the iNOS gene in Tca8113 cells.

Reconstruction of full-thickness cheek defects with combined temporalis myofacial and facial-cervico-pectoral flaps.

OBJECTIVE: The objective of this study was to assess using the temporal myofacial flaps (TMFF) and the facial-cervico-pectoral flap (FCPF) to provide both inner and outer linings for large full-thickness cheek defects following ablative oral cancer surgery. STUDY DESIGN: Twelve patients with malignant tumors in the buccal region were treated by extensive surgical dissection, and the cheek mucosa defects were repaired with the TMFF and the cheek skin defects were reconstructed with the FCPF. There were 9 male and 3 female patients, age range from 18 to 70 years (mean 52.8). The full-thickness cheek defects ranged from 7 x 6 cm to 10 x 8 cm in size. RESULTS: No patient had complete loss of flap; 3 patients had minor complications (TMFF and FCPF partial necrosis and FCPF distal dehiscence) all of which settled with conservative management. Mouth opening was normal in 10 patients, and facial contour was satisfactory in 8 patients. The follow-up period varied from 6 to 26 months (mean 15.2); 3 tumors had local recurrences and 2 patients died from tumor metastasis. CONCLUSION: We found the technique to be anatomically sound, technically easy and reliable, and believe it is a useful method for the reconstruction of large full-thickness cheek defects.

[Expression of inducible nitric oxide synthase mRNA in squamous cell carcinoma of tongue].

BACKGROUND & OBJECTIVE: Recently, most of studies have indicated that nitric oxide (NO) plays an important role in carcinogenesis and tumor progression. Inducible nitric oxide synthase(iNOS) has been found at significantly higher expression levels in head and neck squamous cell carcinoma (HNSCCA) specimens as compared with that in normal tissue. Furthermore, these data provided strong evidance for the role of iNOS generating NO in HNSCCA progression. However, there was no report about whether expression of iNOS mRNA in oral carcinoma is associated with its biological behavior. This study was designed to investigate the correlation between expression of inducible nitric oxide synthase mRNA (iNOS mRNA) in squamous cell carcinoma of tongue tissue and its invasive growth, neck lymph node metastasis, and prognosis. METHODS: Sixty-eight cases with squamous cell carcinoma of tongue tissues were investigated. All cases with tongue carcinoma were followed up to obtain the information of prognosis. In situ hybridization assay was used to detect the expression of iNOS mRNA in tongue carcinoma tissues. The correlation between expression of iNOS mRNA in squamous cell carcinoma of tongue tissue and its invasive growth, neck lymph node metastasis, and prognosis was analyzed. RESULTS: 1. The positive expression rate of iNOS mRNA was 86.1% and 48.0% in the group of invasive growth and no invasive growth respectively. The difference between the two groups was significant with coefficient of 0.3. 2. The positive expression rate of iNOS mRNA was 85.7% and 62.5% in the group of positive lymph node metastasis and negative lymph node metastasis respectively. The difference between the two groups was significant, which the correlation coefficient was 0.3. 3. Three-year survival rate was significantly lower in the group of positive expression of iNOS mRNA than that in the group of negative expression of iNOS mRNA in the tongue carcinoma. CONCLUSIONS: 1. A positive correlation was found between the positive expression of iNOS mRNA and invasive growth as well as neck lymph node metastatsis of squamous cell carcinoma of tongue. 2. The patient's prognosis of the positive expression of iNOS mRNA would be worse than that of the negative expression of iNOS mRNA in tongue carcinoma tissue.