[Establishment of a patient-derived xenograft humanized mouse model for hepatoblastoma in children].

Objective: To establish a patient-derived xenograft (PDX) humanized mouse model for hepatoblastoma in children. In addition, compare the biological consistency between successfully modeled PDX tumors and primary tumors in children while comparing and analyzing the influence of PDX model modeling success as a key factor. Methods: A PDX tumor model was constructed from fresh tumor tissue samples from 39 children with hepatoblastoma. The tumor growth time and volume size were recorded in detail. Simultaneously, 39 children's data were collected for experimental and clinical analysis. The difference in tumorigenesis rate between different parameters was analyzed by χ (2) test (categorical variable). Continuous variables with a normal distribution were compared using the t-test. Results: After cell passage and pathological diagnosis, 21 cases of hepatoblastoma PDX models were successfully constructed, with a success rate of 53.8% (21/39). Tumor samples from each generation of successfully modeled PDX models had pathology results that were consistent with those of the corresponding primary tumors. The analysis of the key factors affecting the tumor formation rate of PDX revealed that the metastasis rate was more successful in primary tumors than in liver in situ tumors (7/8 vs. 14/31, P = 0.049). However, there was no significant difference between tumor formation rates and pathological subtypes. According to the PDX tumor formation group comparison between the primary tumor and the metastatic tumor, there was no statistically significant difference between the two groups in terms of tumor formation time and tumor volume. Hematoxylin-eosin staining in hepatoblastoma's PDX mouse was consistent with the primary tumor. Immunohistochemistry positivity rates of four proteins, namely hepatocyte antigen (Hepatocyte), phosphatidylinositol glycan 3, ß-catenin, and alpha-fetoprotein, in primary tumor tissues and PDX mouse models were 100% vs. 100%, 100% vs. 95.24%, 100% vs. 100%, and 95.24% vs. 85.71%, respectively. Conclusion: A PDX mouse model for hepatoblastoma has been successfully established in children. The tumor formation rate is high, with metastatic tumors having a higher tumor formation rate than primary tumors and transplanted tumors retaining the biological characteristics of primary tumors.

Sitagliptin improves cardiac function after myocardial infarction through activation of autophagy in streptozotocin-induced diabetic mice.

OBJECTIVE: The aim of this study was to investigate the protective effect of sitagliptin on cardiac function in mice with diabetes and myocardial infarction (MI), and to explore its possible mechanism using the mouse models of diabetes and MI. MATERIALS AND METHODS: The models of diabetes and MI were established using C57BL/6 mice. All mice were randomly divided into 5 groups, including the control sham (CS) group, the control MI (CMI) group, the diabetes sham (DS) group, diabetes + MI (DMI) group and the DMI + sitagliptin (DMI+SGL) group. After modeling, mice in the DMI+SGL group were intragastrically administrated with sitagliptin (10 mg/kg/day) for 21 d and the survival rate of mice was recorded. Before and 7, 14, 21 days after MI, the cardiac function of mice in each group was detected via ultrasound. 21 days after MI, the area of MI was measured via 2,3,5-triphenyl tetrazolium chloride (TTC). Meanwhile, the degree of fibrosis in the peripheral region of MI was determined via Masson staining. Moreover, myocardial autophagosomes of mice in each group were observed by transmission electron microscope (TEM). 7 days after MI, the expressions of autophagy-related proteins LC3II and P65 were detected via Western blotting. The expressions of myocardial inflammatory factors, interleukin-1ß (IL-1ß), IL-6 and tumor necrosis factor-α (TNF-α) were detected via enzyme-linked immunosorbent assay (ELISA). In addition, the expression of nuclear factor-κB (NF-κB) was also detected via Western blotting. RESULTS: Sitagliptin increased survival rate, improved cardiac function, reduced infarction area, alleviated myocardial fibrosis, enhanced autophagy in the peripheral region and inhibited inflammation in the peripheral region in mice with diabetes after MI. CONCLUSIONS: Sitagliptin can improve cardiac function and reduce the mortality rate in diabetic rats after MI. The possible underlying mechanism may be related to the fact that sitagliptin activates autophagy and inhibits inflammatory response in diabetes after MI.

[Treatment and prognostic analysis of retinoblastoma patients with choroid invasion].

Objective: To observe the treatment and prognosis of choroid invasion of retinoblastoma (RB) in children. Method: A total of 149 children who had been diagnosed with unilateral RB and received enucleation disclosing tumor invasion to choroid from January 2006 to December 2013 in Beijing Tongren Hospital were recruited in this study. Choroid involvement was classified as massive choroid invasion and focal choroid invasion. Massive choroid invasion was defined as a maximum diameter of invasive tumor focus of 3 mm or more in diameter that might reach the scleral tissue. Focal choroid invasion was defined as a tumor focus of less than 3 mm in diameter without involvement of sclera. The treatment was delivered according to the invasive status of tumor with combination of histopathological high risk factors. The prognosis of different degrees of choroid invasion was observed. They were divided into two groups according to whether the merger of other high histopathologic risk factors, the survival situation was compared. The subjects were followed up for 1 to 9 years (the median follow-up time: 4 years and 1 month). Result: Among the 149 subjects, 90 were boys and 59 were girls. The right eye was affected in 81 patients and the left eye in 68 patients. Sixteen patients died, resulting in an overall survival rate of 89.3%. Among massive choroid invasion in 47 cases, 9 patients experienced disease recurrence and death resulting in a survival rate of 80.9%. While the focal choroid invasion was found in 102 cases, only 7 children had disease relapsed and died resulting in a survival rate of 93.1% which was statistically significant (χ2=5.067, P=0.024). Among 8 patients with massive choroid invasion without pathological high-risk factors, no death occurred, while in other 39 patients with high-risk factors, 9 died with a mortality rate of 23.1%, however, the difference was not statistically significant (Fisher's exact probability method, P=0.323). Among 60 patients with focal choroid invasion without pathological high-risk factors, no death was observed, while among the other 42 patients presenting high-risk factors, 7 of them died with a mortality rate of 16.7% (Fisher's exact probability method, P=0.003). Cox multivariate analysis showed that massive choroid invasion and surgical margin of the optic nerve were influential factors of prognosis. Conclusion: Patients with focal choroid invasion have a low disease recurrence and may not receive adjuvant chemotherapy. Patients with massive choroid invasion without presenting pathological high-risk factors warrant further prospective study to assess whether adjuvant chemotherapy is needed. However chemotherapy is recommended for those with massive choroid invasion presenting with risk factors to avoid the high disease recurrence in such patients.

[Effect of different concentrations of ammonium chloride on expression of hypoxia-inducible factor-1α in Chang liver cells].

Objective: To investigate the effect of treatment with different concentrations of ammonium chloride (NH4Cl) on the mRNA and protein expression of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) in Chang liver cells. Methods: Normal Chang liver cells were cultured and treated continuously with different concentrations of NH4Cl (1.25, 2.5, and 5 mmol/L). The Chang liver cells cultured normally were used as controls. RNA and protein were extracted at the 5th, 10th, and 15th generations. Quantitative real-time PCR, immunohistochemistry, and Western blot were used to measure the expression of HIF-1α and VEGF. Results: Quantitative real-time PCR showed that compared with the control group, the NH4Cl treatment group showed significant increases in the mRNA expression of HIF-1α and VEGF across the 5th, 10th, and 15th generations (F = 90976.659/1300.218/1896.800 and 41825.754/2381.321/2591.954, all P < 0.05). The results of immunohistochemistry showed that compared with the control group, the NH4Cl treatment group showed significant increases in the protein expression of HIF-1α and VEGF across the 5th, 10th, and 15th generations (F = 376.709/1615.358/1350.120 and 904.789/5105.186/8644.498, all P < 0.05). As was shown by the results of Western blot, compared with the control group, the NH4Cl treatment group showed significant increases in the protein expression of HIF-1α and VEGF across the 5th, 10th, and 15th generations (F = 228.499/6051.974/183.219 and 5549.429/40187.665/120982.183, all P < 0.05). Conclusion: Ammonia can increase the expression of HIF-1α and its downstream gene VEGF in Chang liver cells and cause the phenomenon of pseudohypoxemia.

The role of IVS14+1 G > A genotype detection in the dihydropyrimidine dehydrogenase gene and pharmacokinetic monitoring of 5-fluorouracil in the individualized adjustment of 5-fluorouracil for patients with local advanced and metastatic colorectal cancer: a preliminary report.

AIM: We retrospectively investigated the relationship between IVS14+1 G > A genotype of the dihydropyrimidine dehydrogenase (DPD) gene with plasma concentration of 5-fluorouracil (5-FU) as well as adverse reactions in 80 patients with locally advanced or metastatic colorectal cancer. PATIENTS AND METHODS: Eighty patients with un-resectable locally advanced or metastatic colorectal cancer were treated with Folfox-6 regimen, which repeated every two weeks for at least three cycles. Single nucleotide polymorphisms for DPD gene were analyzed before chemotherapy by high-resolution melting (HRM) analysis. The plasma concentration of fluorouracil was measured by high performance liquid chromatography (HPLC) after continuous infusion of fluorouracil over 12 h in each cycle. The average values of plasma concentrations in each cycle were calculated, and the factors related to plasma concentration of 5-FU were screened by stepwise regression. RESULTS: All patients were divided into three groups according to the predictive confidence interval of plasma concentration of 5-FU, and the average plasma concentrations of fluorouracil in each cycle of these three groups were less than or equal to 26.83 mg/L, 26.83-40.62 mg/L, and more than 40.62 mg/L, respectively. Stepwise regression analysis showed that the plasma concentration of fluorouracil was associated with myelosuppression, hand-foot syndrome, diarrhea, overall survival (OS) and DPD genotype. In efficacy, the median progression-free survival PFS (mPFS) and OS (mOS) of group 2 and group 3 were both significantly higher than those of group 1. CONCLUSIONS: Among the advanced colorectal cancer patients receiving fluorouracil-based chemotherapy, those with plasma concentration of 5-FU above 26.83 mg/L can obtain better survival; for patients with heterozygous DPD IVS14+1 mutation, 5-FU dose should be appropriately reduced according to last plasma concentration to reduce adverse reactions, while the homozygous ones should avoid application of 5-FU and its derivatives.

Glycerol production by a novel osmotolerant yeast Candida glycerinogenes.

Candida glycerinogenes, an osmotolerant yeast isolated from a natural sample in an environment of high osmotic pressure, had a modest sugar-tolerance and an extremely high glycerol productivity. The optimum conditions for glycerol formation by C. glycerinogenes were a temperature of 29-33 degrees C and a pH of 4-6. The optimum medium for glycerol production consisted of 230-250 g glucose/l, 2 g urea/l and 5 ml corn steep liquor/l (55-65 mg phosphates/l); the pH was not adjusted. The highest yield of glycerol was 64.5% (w/w) based on consumed glucose from 240 g glucose/l, and the highest concentration of glycerol was 137 g/l from 260 g glucose/l. These results were obtained by using a 30-l agitated fermentor under optimal fermentation conditions. In ten batch-fermentations carried out in a 50,000-l airlift fermentor, an average yield of glycerol of 50.67% (w/w) and an average glycerol concentration of 121.9 g/l were obtained from an average 240.6 g glucose/l.