Effect of ligation of the thoracic duct during oesophagectomy on the absorption of D-xylose

Objective: To assess if prophylactic thoracic duct ligation during oesophagectomy influences the absorptive function of oesophageal cancer patients

Study Design: Randomized controlled trial

Place and Duration of Study: Department of Thoracic Surgery, Tai'an City Central Hospital, Tai'an, from August 2014 to December 2015

Methodology: Based on the management of the thoracic duct during oesophagectomy, 60 patients were randomized into two groups. D-xylose absorption test was used to evaluate the absorptive function. The two-independent-samples t-test was employed for statistical analysis with statistical significance at p < 0.05

Results: The serum D-xylose concentration of ligation-group was significantly lower than that of no-ligation group on the first day after operation, [t=2.82, p=0.0066]. However, there was no significant differences between them even before operation [t=1.34, p=0.1849]

Conclusion: Ligation of the thoracic duct during oesophagectomy immediately affected the absorption of D-xylose, which may lead to malabsorption in the long run

The coupling mechanism of connexin 43 and aquaporin 4 together inducing brain edema formation in glioma / 肿瘤

Objective: To search for the coupling mechanism of connexin 43 (CX43) and aquaporin 4 (AQP4) together inducing brain edema formation in glioma. Methods: Intracranial C6 glioma xenograft models were established in the rats, then magnetic resonance imaging detection was used to find the tumor and brain edema, and immunofluorescence and Western blotting method were used to detect CX43 and AQP4 expressions in both intratumoral and peritumoral tissues. C6 glioma cells and normal glial cells were cultured in hypotonic medium, then RT-PCR (reverse transcription-PCR) was used to detect and compare CX43 and AQP4 mRNA expression trends. AQP4 or CX43 expression was silenced in C6 glioma cells and normal glial cells by siRNA (small interference RNA) technology, then the other genetic change was detected by RT-PCR. Results: In C6 glioma xenograft models, CX43 expression was missed and AQP4 expression was slightly elevated in the intratumoral tissues. But in the peritumoral tissues, CX43 expression was slightly elevated and AQP4 expression was significantly increased. In vitro, the hypotonic environment induced elevation of AQP4 and CX43 mRNA levels with time-varying degrees in both normal glial cells and C6 glioma cells, but the change degree of normal glial cells was significantly lower than that of tumor cells, and the time window of CX43 changes was backward of AQP4. The elevated degree of CX43 was significantly decreased when AQP4 expression was silenced by siRNA in C6 cells (P 0.05). Conclusion: There are two different mechanisms of AQP4 and CX43 inducing brain edema formation intratumorally and in the edge of glioma. CX43 may be one of the potential downstream regulatory factors of AQP4. Copyright © 2013 by TUMOR.

Inhibitory effect of folic acid/polyamide-amine as a miR-7 vector on the growth of glioma in mice / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To explore if folic acid/polyamide-amine (FA/PAMAM) enhances the therapeutic effect of miR-7gene therapy for glioma in vivo.</p><p><b>METHODS</b>The miR-7 gene was transfected into U251 glioma cells by FA/PAMAM. The efficiency of gene transfection was assessed by fluorescence microscopy. The miR-7 level was detect by quantitative RT-PCR. Intracranial glioma models were established in thymectomized mice, and FA/PAMAM nanoparticles were transplanted into the tumors in situ 3 days later. The animal survival was recorded and the gross tumor volume and degree of edema were observed by MRI. Apoptosis in the glioma cells and expression of proliferating cell nuclear antigen (PCNA), matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9) were assessed by immunohistochemistry, and EGFR and AKT-2 protein expression was detected by Western blot assay.</p><p><b>RESULTS</b>Compared with the liposomes, the FA/PAMAM nanoparticles were more efficient to transfer miR-7 gene into U251 glioma cells, MRI showed that the tumor growth was much slower in the FA/PAMAM/miR-7 group, and the animal survival time was longer. The apoptosis rate was (5.3 ± 0.9)% in the control group, (11.4 ± 2.4)% in the liposome/miR-7 group, and (17.7 ± 3.7)% in the FA/PAMAM/miR-7 group. The immunohistochemical assay showed that the levels of PCNA, MMP-2 and MMP-9 protein in the FA/PAMAM/miR-7 group were (34.6 ± 5.4)%, (24.5 ± 4.1)%, (25.4 ± 5.1)%, respectively, significantly lower than those in the liposome/miR-7 group (49.3 ± 5.9)%, (31.7 ± 7.1)% and (39.4 ± 6.4)%, respectively, and those in the control group (57.3 ± 7.4)%, (45.4 ± 6.9)% and (55.1 ± 7.3)%, respectively (all P < 0.05). The expressions of EGFR and AKT-2 proteins were 1.09 ± 0.12 and 0.62 ± 0.10 in the control group, 0.63 ± 0.11 and 0.43 ± 0.07 in the liposome/miR-7 group, and significantly deceased (0.47 ± 0.09 and 0.31 ± 0.04, respectively) in the FA/PAMAM/miR-7 group (all P < 0.05).</p><p><b>CONCLUSION</b>Compared with the liposomes, FA/PAMAM can transfect miR-7 into glioma cells with a higher efficiency in vivo, makes a longer time of the drug action, and shows a certain inhibitory effect on the growth of glioma, therefore, might become a new drug targeting agent in gene therapy forglioma.</p>

Study on reversion of malignant phenotype of glioma by siRNA targeting p75 neurotrophin receptor / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the therapeutic efficacy of siRNA fragments silencing p75 neurotrophin receptor (p75(NTR)), which may be a key regulator of glioma cell apoptosis and invasion.</p><p><b>METHODS</b>The siRNA sequence fragments targeting p75(NTR) were designed and transferred into human glioma cell line U251. RT-PCR and immunocytochemistry method were used to explore the expression of p75(NTR) mRNA and protein. Cell adhesion assay was employed to detect cellular adhesion ability, and soft agar clone formation assay was adopted to identify oncogenicity, and a U251 glioma model was established in nude mice. The intracranial tumor volume was detected by MRI. The expression of p75(NTR), NGF and cyclin D2 were identified using immunohistochemistry. Cell apoptosis was detected by apoptosis kit in situ.</p><p><b>RESULTS</b>The siRNA fragments targeting p75(NTR) were capable of decreasing mRNA and protein expression of p75(NTR) in U251 glioma cell line. Both the cellular adhesion ability and oncogenicity were weakly relevant. The p75(NTR) expression level was negatively correlated with cyclin D2 and apoptosis, and positively correlated with NGF expression. The siRNA sequence fragments targeting p75(NTR) were effective in decreasing the gross volume of tumor; prolonged the survival time of mice, and the edge of tumor was much sharper than that of the control group.</p><p><b>CONCLUSIONS</b>The gene silencing technique by siRNA targeting p75(NTR) is capable of decreasing tumor invasion and cell proliferation as well as inducing cell apoptosis. It is expected to be a new choice for glioma gene therapy.</p>

Differential proteomics in glioblastoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To establish differential proteomics profiles of glioblastoma cell lines from Chinese, and to provide reference for future basic studies.</p><p><b>METHODS</b>Total protein was extracted from 3 glioblastoma cell lines, CHG-5, TJ899 and TJ905. After normalization, the total protein was presented by two-dimensional (2D) electrophoresis, scanned and analyzed. Some of the identified protein spots were verified by immunocytochemistry of cell lines and immunohistochemistry of solid tumors. The glia cells were used as the control throughout the study.</p><p><b>RESULTS</b>A total of 13 differential protein spots were selected, and eventually 10 were identified as unique proteins. These 10 proteins were involved in cytoskeleton forming, cellular metabolism, tumor migration, stress and inflammatory reaction. Immunocytochemistry and immunohistochemistry further confirmed these proteins present in the solid tumors.</p><p><b>CONCLUSION</b>Distinct differential proteomics profiles exist in glioblastoma cell lines and normal glia cells, likely related to the transformation of normal glia to glioma.</p>