Radiotherapy Combined with PD-L1 Antibody Exerts a Synergistic Anti-tumor Effect in a Mouse Model of Esophageal Squamous Cell Carcinoma

PURPOSE/OBJECTIVE(S)

The combination of radiotherapy and immune checkpoint inhibitors (ICIs) has been shown to exert synergistic anti-tumor effects in various tumors. In esophageal squamous cell carcinoma (ESCC), several clinical trials of radiotherapy combined with ICIs are undergoing or have been finished. However, the efficacy and action mechanisms of radiotherapy combined with ICIs is still not clear in ESCC. Our study aimed to investigate whether radiotherapy improved the anti-cancer effect of PD-L1 antibody and the effect of this combination therapy on tumor-immune microenvironment.

MATERIALS/METHODS

The mouse esophageal cancer cell line mEC25 was implanted into the armpits of female C57 mice. When the tumor volume grew to 150-250 mm3, the mice were randomly divided into different groups including control group (administration of IgG antibody), radiotherapy group (12 Gy at 4 Gy per fraction), PD-L1 antibody group (200 mg/kg i.p. for three times) and combination group (fractionated radiation combined with PD-L1 antibody was delivered on day 1, day 4 and day 7, the day when fractionated radiation began was recorded as day 1).The mice were sacrificed on the 1st, 3rd and 7th day after the treatment was ended. The tumor, spleen and draining lymph nodes of the mice were collected and analyzed using flow cytometry (FCM), and the tumor volume and survival time of mice were calculated.

RESULTS

Compared with radiotherapy or PD-L1 antibody alone, the combination therapy significantly prolonged the survival time of mice and decreased the growth rate of xenograft tumors FCM analysis showed that the combination therapy significantly increased the infiltration and cytotoxicity of effector T cells and reduced the proportion of M2 macrophages in tumor, spleen and lymph nodes. In addition, in tumor and spleen, the proportion of regulatory T cells (Tregs) decreased in the group of combination therapy. In tumor, spleen, and lymph nodes, the proportion of central memory T cell (TCM) was increased in the group of combination therapy.

CONCLUSION

The anti-tumor effect of radiotherapy combined with PD-L1 antibody is superior to single treatment in the mouse model of esophageal cancer. Radiotherapy can shape tumor-immune microenvironment, allowing the infiltration of effector T cells and exclusion of immune-suppressive cells such as M2 macrophages and Tregs.

The Role of Esophagography in the Diagnosis of Orthotopic Esophageal Squamous Cell Carcinoma in a Mouse Mode

PURPOSE/OBJECTIVE(S)

Animal models play an irreplaceable role in pre-clinical studies of various tumors, mainly including xenogeneic/homograft subcutaneous tumor models. However, the subcutaneous transplanted tumor model is separated from the microenvironment of the primary tissue and fail to accurately simulate the growth of tumor cells in vivo. Therefore, orthotopic tumor models play an increasingly important role. For esophageal squamous cell carcinoma, chemotherapy-induced methods have successfully established mouse models of esophageal squamous cell carcinoma, but past experiments have found that it is still a challenge to confirm the success of the mouse model of esophageal cancer. The pathological diagnosis of the esophageal cancer tissue obtained from the killed mouse model remains the gold standard, but it also represents a lost opportunity to evaluate the efficacy of subsequent treatment. Notedly, esophagography is the primary examination for clinical patients with esophageal cancer. Therefore, the aim of this study is to evaluate whether esophagography can be used to establish a successful in situ mouse model of esophageal cancer.

MATERIALS/METHODS

Referring to previous literature, we used the chemical drug 4-Nitroquinoline N-oxide (4-NQO) to induce orthotopic tumor model: A certain amount of 4-NQO was dissolved in propylene glycol to make a 2% stock solution, and then dissolved in 200ml of sterile water for the daily drinking water of mice. The water was kept in the dark and replaced once a week. After 16 weeks of induction, the drinking water was replaced by the same volume of sterile water and continued to be fed for 12 weeks. The mice were subsequently subjected to esophagography: First, the mice were fixed on a plastic plate, and the gavage needle was slowly inserted into the stomach, then slowly withdrawn out and gradually injected with meglumine diphosphate, with a total amount of 0.1-0.2ml. Then the radiolucent film was taken immediately, and three positions were selected, including the plain film, the standing film and the lateral film. After that, the mice were sacrificed and the esophagus of the mice was isolated and embedded in sections for pathological and immunohistochemical diagnosis. Finally, the results were compared with the imaging results.

RESULTS

Based on the comparison of imaging and pathological results, we found that most of the esophageal segments with filling defects on esophagography were pathologically diagnosed as esophageal squamous cell carcinoma, and another part were diagnosed as esophageal papilloma. Compared with CT and MRI, esophagography has the advantages of simple operation and less consumable materials.

CONCLUSION

We found that esophagography is a new non-invasive auxiliary diagnostic method for the successful establishment of an orthotopic mouse model of esophageal squamous cell carcinoma.

Toxic Effects of Thioacetamide-Induced Femoral Damage in New Zealand White Rabbits by Activating the p38/ERK Signaling Pathway

Thioacetamide (TAA) is widely used in the production of drugs, pesticides and dyeing auxiliaries. Moreover, it is a chemical that can cause liver damage and cancer. TAA has recently been identified to cause bone damage in animal models. However, the type of bone damage that TAA causes and its potential pathogenic mechanisms remain unclear. The toxic effects of TAA on the femurs of New Zealand white rabbits and the underlying toxicity mechanism were investigated in this study. Serum samples, the heart, liver, kidney and femurs were collected from rabbits after intraperitoneal injection of TAA for 5 months (100 and 200 mg/kg). The New Zealand white rabbits treated with TAA showed significant weight loss and femoral shortening. The activities of total bilirubin, total bile acid and gamma-glutamyl transpeptidase in the serum were increased following treatment with TAA. In addition, the cortical bone became thinner, and the trabecular thickness decreased significantly in TAA-treated rabbits, which was accompanied by significantly decreased mineral density of the cortical and trabecular bone. Moreover, there was a significant decrease in modulus of elasticity and maximum load on bone stress in TAA-treated rabbits. The western blotting results showed that the expression of phosphorylated (p)-p38 and p-ERK in femur tissues of rabbits were increased after TAA administration. Collectively, these results suggested that TAA may lead to femoral damage in rabbits by activating the p38/ERK signaling pathway.

AmAMP1 from Acropora millepora and damicornin define a family of coral-specific antimicrobial peptides related to the Shk toxins of sea anemones

A candidate antimicrobial peptide (AmAMP1) was identified by searching the whole genome sequence of Acropora millepora for short (<125AA) cysteine-rich predicted proteins with an N-terminal signal peptide but lacking clear homologs in the SwissProt database. It resembled but was not closely related to damicornin, the only other known AMP from a coral, and was shown to be active against both Gram-negative and Gram-positive bacteria. These proteins define a family of AMPs present in corals and their close relatives, the Corallimorpharia, and are synthesised as preproproteins in which the C-terminal mature peptide contains a conserved arrangement of six cysteine residues. Consistent with the idea of a common origin for AMPs and toxins, this Cys motif is shared between the coral AMPs and the Shk neurotoxins of sea anemones. AmAMP1 is expressed at late stages of coral development, in ectodermal cells that resemble the "ganglion neurons" of Hydra, in which it has recently been demonstrated that a distinct AMP known as NDA-1 is expressed.

The relationship of platelet to lymphocyte ratio and neutrophil to monocyte ratio to radiographic grades of knee osteoarthritis

OBJECTIVE

Accumulating data show that platelet to lymphocyte ratio (PLR) and neutrophil to monocyte ratio (NMR) undergo changes during inflammation in various diseases; however, the clinical features remain unclear in knee osteoarthritis (OA) patients. The purpose of our study was to evaluate PLR and NMR in knee OA patients, and assess their relationship to knee OA's radiographic grades.

METHODS

A retrospective study on 132 adult knee OA patients and 162 healthy controls (HC) was performed. All clinical characteristics of the knee OA patients were obtained from their medical records. PLR and NMR were compared between knee OA patients and HC by non-parametric tests. Correlations of PLR and NMR with Kellgren-Lawrence (KL) classification (KL grade 2, KL grade 3, and KL grade 4) were also analyzed through a Spearman correlation test. Ordinal polytomous logistic regression was used to determine independent factors influencing radiographic grades of knee OA patients.

RESULTS

PLR was increased significantly in knee OA patients, while a statistical difference in NMR was not observed. However, PLR was not relevant to KL grades, while NMR was negatively correlated with these (r = -0.330, P < 0.01) and was independently associated with KL grades of knee OA.

CONCLUSION

PLR could reflect the inflammation response of knee OA. NMR emerged as an independent factor and could be used as a potential marker indicating the severity of knee OA.

Characteristics and Follow-Up of 13 pedigrees with Gitelman syndrome

CONTEXT

Gitelman syndrome (GS) is clinically heterogeneous. The genotype and phenotype correlation has not been well established. Though the long-term prognosis is considered to be favorable, hypokalemia is difficult to cure.

OBJECTIVE

To analyze the clinical and genetic characteristics and treatment of all members of 13 GS pedigrees.

METHODS

Thirteen pedigrees (86 members, 17 GS patients) were enrolled. Symptoms and management, laboratory findings, and genotype-phenotype associations among all the members were analyzed.

RESULTS

The average ages at onset and diagnosis were 27.6 ± 10.2 years and 37.9 ± 11.6 years, respectively. Males were an average of 10 years younger and exhibited more profound hypokalemia than females. Eighteen mutations were detected. Two novel mutations (p.W939X, p.G212S) were predicted to be pathogenic by bioinformatic analysis. GS patients exhibited the lowest blood pressure, serum K⁺, Mg²⁺, and 24-h urinary Ca²⁺ levels. Although blood pressure, serum K⁺ and Mg²⁺ levels were normal in heterozygous carriers, 24-h urinary Na⁺ excretion was significantly increased. During follow-up, only 41.2% of patients reached a normal serum K⁺ level. Over 80% of patients achieved a normal Mg²⁺ level. Patients were taking 2-3 medications at higher doses than usual prescription to stabilize their K⁺ levels. Six patients were taking spironolactone simultaneously, but no significant elevation in the serum K⁺ level was observed.

CONCLUSION

The phenotypic variability of GS and therapeutic strategies deserve further research to improve GS diagnosis and prognosis. Even heterozygous carriers exhibited increased 24-h Na⁺ urine excretion, which may make them more susceptible to diuretic-induced hypokalemia.

Effect of nucleoside analogues in the treatment of hepatitis B cirrhosis and its effect on Th17 cell

OBJECTIVE

We conducted this study to analyze the effects of nucleoside analogues in the treatment of hepatitis B cirrhosis and its effect on Th17 cells.

PATIENTS AND METHODS

120 patients were randomly divided into lamivudine combined with adefovir dipivoxil group (combined group) and entecavir group. There were 59 cases in the combined group and 59 cases in entecavir group. The combined group was administered lamivudine 100 mg/d + adefovir dipivoxil 10 mg/d and entecavir group was administered entecavir 0.5 mg/d. The treatment was continued until there was virus negativity and it maintains for at least 3 months.

RESULTS

The treatment effects were compared. We compared the average rate of viral clearance time and virus clearance of two groups of patients; the difference was not statistically significant (p>0.05). The relapse rate after a negative test of entecavir group was lower than that of the combined group (p<0.05). Before and after treatment, the levels of TBIL, ALT and ALB in the two groups were compared; the differences were not statistically significant (p>0.05). The Th17 cell proportion and the level of IL-17 after treatment of the entecavir group were lower than those before treatment. The combined group exhibited no change, and the entecavir group was lower than combined group; the differences were statistically significant (p<0.05).

CONCLUSIONS

Therefore, the effects of the combination of lamivudine and adefovir dipivoxil is the same as single entecavir treatment of hepatitis B cirrhosis suppression of viral replication. It does not increase liver injury and the antiviral effects of entecavir may be related to inhibition of the expression of Th17 cells and effector molecules IL-17.

Frailty and Health-Related Quality of Life in End Stage Renal Disease Patients of All Ages

BACKGROUND: Frailty is associated with worse health-related quality of life (HRQOL) in older adults and worse clinical outcomes in adults of all ages with end stage renal disease (ESRD). It is unclear whether frail adults of all ages with ESRD are more likely to experience worse HRQOL. OBJECTIVE: The goal of this study was to identify factors associated with worsening HRQOL in this population. DESIGN, SETTING AND MEASUREMENTS: We studied 233 adults of all ages with ESRD enrolled (11/2009-11/2013) in a longitudinal cohort study. Frailty status was measured at enrollment and HRQOL was reported (Excellent, Very Good, Good, Fair or Poor) at the initial assessment and follow-up (median follow-up 9.4 months). We studied factors associated with Fair/Poor HRQOL at follow-up using logistic regression and factors associated with HRQOL change using multinomial regression. All models were adjusted for age, sex, race, education, BMI, diabetes status, history of a previous transplant, type of dialysis and time between assessments. RESULTS: Fair/Poor HRQOL was reported by 28% at initial assessment and 33% at follow-up. 47.2% of participants had stable HRQOL, 22.8% better HRQOL, and 30.0% worse HRQOL at follow-up (P<0.001). In adjusted models, only frailty was associated with Fair/Poor HRQOL at follow-up (OR: 2.79, 95% CI: 1.32-5.90) and worsening HRQOL at follow-up (RR: 2.91, 95%CI: 1.08-7.80). CONCLUSIONS: Frail adults of all ages with ESRD are more likely to experience fair/poor HRQOL and worsening HRQOL over time. Frailty represents a state of decreased physiologic reserve that impacts not only clinical outcomes but also the patient-centered outcome of HRQOL.

Chitosan production from hemicellulose hydrolysate of corn straw: impact of degradation products on Rhizopus oryzae growth and chitosan fermentation

AIMS

To examine the potential use of hemicellulose hydrolysate (HH) for the production of chitosan by Rhizopus oryzae and investigate the influence of contents in HH on mycelia growth and chitosan synthesis.

METHODS AND RESULTS

Compared to xylose medium, HH enhanced mycelia growth, chitosan content and production of R. oryzae by 10.2, 64.5 and 82.1%, respectively. During sulfuric acid hydrolysis of corn straw, sugars (glucose, galactose, etc) and inhibitors (formic acid, acetic acid and furfural) were generated. Acetic acid (2.14 g l(-1)) and formic acid (0.83 g l(-1)) were stimulative, while furfural (0.55 g l(-1)) was inhibitory. Inhibitors, at different concentrations, increased the mycelia growth and chitosan production by 24.5-37.8 and 60.1-207.1%.

CONCLUSIONS

HH of corn straw is a good source for chitosan production. Inhibitors in HH, at proper concentrations, can enhance chitosan production greatly.

SIGNIFICANCE AND IMPACT OF THE STUDY

This work for the first time reported chitosan production from HH. Chitosan production can be greatly enhanced by cheap chemicals such as inhibitors in HH.

Pten and p53 converge on c-Myc to control differentiation, self-renewal, and transformation of normal and neoplastic stem cells in glioblastoma

Glioblastoma (GBM) is a highly lethal primary brain cancer with hallmark features of diffuse invasion, intense apoptosis resistance and florid necrosis, robust angiogenesis, and an immature profile with developmental plasticity. In the course of assessing the developmental consequences of central nervous system (CNS)-specific deletion of p53 and Pten, we observed a penetrant acute-onset malignant glioma phenotype with striking clinical, pathological, and molecular resemblance to primary GBM in humans. This primary, as opposed to secondary, GBM presentation in the mouse prompted genetic analysis of human primary GBM samples that revealed combined p53 and Pten mutations as the most common tumor suppressor defects in primary GBM. On the mechanistic level, the "multiforme" histopathological presentation and immature differentiation marker profile of the murine tumors motivated transcriptomic promoter-binding element and functional studies of neural stem cells (NSCs), which revealed that dual, but not singular, inactivation of p53 and Pten promotes cellular c-Myc activation. This increased c-Myc activity is associated not only with impaired differentiation, enhanced self-renewal capacity of NSCs, and tumor-initiating cells (TICs), but also with maintenance of TIC tumorigenic potential. Together, these murine studies have provided a highly faithful model of primary GBM, revealed a common tumor suppressor mutational pattern in human disease, and established c-Myc as a key component of p53 and Pten cooperative actions in the regulation of normal and malignant stem/progenitor cell differentiation, self-renewal, and tumorigenic potential.

Distinct dysregulation of lipid metabolism by unliganded thyroid hormone receptor isoforms

Thyroid hormone receptors (TRs) play critical roles in energy homeostasis. To understand the role of TRs in lipid homeostasis in vivo, we adopted the loss-of-function approach by creating knock-in mutant mice with targeted mutation in the TRalpha gene (TRalpha1PV mouse) or TRbeta gene (TRbetaPV mouse). The PV mutation, identified in a patient with resistance to thyroid hormone, exhibits potent dominant-negative activity. Here we show that in contrast to TRalpha1PV mouse, TRbetaPV mice exhibited no significant reduction in WAT but had significant increases in serum free fatty acids and total triglycerides. Moreover, the liver of TRbetaPV mice was markedly increased (33%) with excess lipid accumulation, but the liver mass of TRalpha1PV mouse was decreased (23%) with paucity of lipids. These results indicate that apo-TRbeta and apo-TRalpha1 exerted distinct abnormalities in lipid metabolism. Further biochemical analyses indicate that increased lipogenic enzyme expression, activated peroxisome proliferator-activated receptor gamma (Ppargamma) signaling, and decreased fatty acid beta-oxidation activity contributed to the adipogenic steatosis and lipid accumulation in the liver of TRbetaPV mice. In contrast, the expression of lipogenic enzymes and Ppargamma was decreased in the liver of TRalpha1PV mice. These results suggest that the regulation of genes critical for lipid metabolism by TRs in the liver is isoform dependent. These results indicate that apo-TRbeta and apo-TRalpha1 had different effects on lipid metabolism and that both TR isoforms contribute to the pathogenesis of lipid metabolism in hypothyroidism.

Decision Making in Fuzzy Discrete Event Systems1

The primary goal of the study presented in this paper is to develop a novel and comprehensive approach to decision making using fuzzy discrete event systems (FDES) and to apply such an approach to real-world problems. At the theoretical front, we develop a new control architecture of FDES as a way of decision making, which includes a FDES decision model, a fuzzy objective generator for generating optimal control objectives, and a control scheme using both disablement and enforcement. We develop an online approach to dealing with the optimal control problem efficiently. As an application, we apply the approach to HIV/AIDS treatment planning, a technical challenge since AIDS is one of the most complex diseases to treat. We build a FDES decision model for HIV/AIDS treatment based on expert's knowledge, treatment guidelines, clinic trials, patient database statistics, and other available information. Our preliminary retrospective evaluation shows that the approach is capable of generating optimal control objectives for real patients in our AIDS clinic database and is able to apply our online approach to deciding an optimal treatment regimen for each patient. In the process, we have developed methods to resolve the following two new theoretical issues that have not been addressed in the literature: (1) the optimal control problem has state dependent performance index and hence it is not monotonic, (2) the state space of a FDES is infinite.