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  • Kilic posted an update 7 months, 2 weeks ago

    Quercetin is a natural product that has been shown to induce tumor apoptosis and necrosis through multiple mechanisms. Tumor-induced myeloid-derived suppressor cell (MDSC) expansion negatively regulates the immune response by inhibiting T cell function through signal transducer and activator of transcription 3 (STAT3) activation, thereby facilitating tumor escape from host immune surveillance. Thus MDSC is an attractive target for cancer immunotherapy to enhance cytotoxic T cell responses. However, the effects of quercetin on MDSC are poorly understood. Here, we demonstrate that quercetin treatment enhanced mouse- and human- derived granulocytic-myeloid-derived suppressor cells (G-MDSC) survival and promoted the secretion of T cell-suppressive factors in vitro. Bioinformatics analysis further showed that quercetin was highly correlated with the estrogen receptor signaling pathway, which was confirmed by quantitative reverse transcription-polymerase chain reaction and flow cytometric analysis. These findings highlight the potential advantages and feasibility of quercetin in reinforcing the suppressive property of G-MDSC. Thus impact of G-MDSC should be taken into consideration when quercetin is applied to tumor therapy. Cisplatin (DDP) is the first-line drug for the treatment of gastric cancer (GC). However, DDP resistance is common. Autophagy, which is closely related to chemoresistance, is a process of resolving and recycling proteins and damaged cellular organs. Additionally, O-6-methylguanine-DNA methyltransferase (MGMT) is responsible for alkylating drug resistance. However, the relationship between autophagy and MGMT in response to DDP in GC is still unknown. In the present study, we determined that autophagy induced by DDP decreases chemosensitivity in GC cell lines. DDP may have induced autophagy in GC by inhibiting MGMT to increase autophagy-related gene (ATG) 4B. Inhibition of MGMT-mediated ATG4B suppression resulted in autophagy induction and DDP resistance. In vivo, combined DDP and autophagy inhibitor chloroquine (CQ) enhanced the anti-tumor effect of DDP; additionally, the negative correlation of MGMT and ATG4B was confirmed. High expression of MGMT and low expression of ATG4B were significantly correlated with favorable five-year survival rate (P  less then   0.05) in 66 clinicopathologically characterized GC cases. Our study demonstrate that DDP inhibits MGMT-mediated autophagy suppression to decrease chemosensitivity in GC, which provides a novel therapeutic strategy to promote DDP chemosensitivity in GC. BACKGROUND AND PURPOSE Multidrug resistance (MDR) is a great challenge and obstacle in cancer treatment. It is a common problem in the treatment of acute myeloid leukemia (AML). Whether grape seed proanthocyanidin extract (GSPE) could reverse MDR in patients with AML is still unknown. The aim of this study was to investigate the MDR reverse ability of GSPE and its possible mechanism in vitro. MATERIALS AND METHODS Human leukemia cell line HL-60 cells and HL-ADR cells were used. MTT assay were employed to identify the cytotoxic effects of different chemotherapeutic drugs and reverse ability of GSPE. Flow cytometry assays were used to verify the cell apoptosis induced by GSPE. MDR-related genes expression was tested by real-time polymerase chain reaction (Q-PCR). MDR-related protein expression was assessed by Western blotting assays. The genes and their related protein expression of multidrug resistance-associated protein 1 (MRP1), multidrug resistance protein 1 (MDR1) and lung resistance-related protein (LRP) be associated with the inhibition of the PI3K/Akt signaling pathway, which resulted in the down-regulation the expression of MRP1, MDR1 and LRP. These results provide that GSPE may serve as a combination therapy in AML chemotherapy for future study. Ixeris sonchifolia (IS), principally its dried form, is widely used as traditional and folk medicines in some Asian countries, especially China. In this review, we summarized its traditional uses, chemical constituents, quality control measures, pharmacological activities, therapeutic evaluation, toxicity evaluation and clinical applications. 130 chemical constituents isolated from IS have been reported, including flavones, sesquiterpenes, triterpenes, phenylpropanoids, organic acids and others. They showed various pharmacological activities, such as protecting cardiocerebral vascular system, anticancer effect and antiviral etc. The quality control evaluation studies, clinical applications, other possible applications and suggestions for future research also were discussed. The aim of this review is to critically appraise the available literature and suggest directions for further development of IS to improve its medical value and use. BACKGROUND To evaluate whether the level of myeloid-derived suppressor cells is related to the complication of sepsis after esophageal cancer surgery and whether changing the myeloid-derived suppressor cells levels can improve the prognosis of patients cancer-related sepsis. METHODS A total of 178 esophageal cancer patients from Harbin Medical University Cancer Hospital were included in this study. Blood samples were taken from the patients for the analysis of the levels of G-MDSCs and M-MDSCs by flow cytometry. The conditions of the patients was recorded. Male C57BL/6 mice were implanted with Lewis lung cancer cells (2 × 106/mice) by subcutaneous injection into the iliac fossa. Three weeks later, we performed CLP in the mice. All-trans-retinoic acid (ATRA) was intraperitoneally injected at 20 mg/kg, and the control group was injected with 0.9 % NS. We observed the mortality of the mice with cancer-related sepsis. RESULTS In all, 95 % of the esophageal cancer patients had a high level of G-MDSCs (>50 %). A high level of G-MDSCs (>82.5 %) can lead to high morbidity from sepsis after surgery. The increase in M-MDSCs was suggestive of a poor prognosis in patients with cancer-related sepsis. selleck inhibitor ATRA can improve the survival of patients with cancer-related sepsis. CONCLUSIONS A high level of G-MDSCs can be used to determine the incidence of sepsis in preoperative esophageal cancer patients, M-MDSCs might be effective prognostic indicators for cancer-sepsis patients, and changing the MDSC levels can improve the mortality of patients with cancer-related sepsis.

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