Zhaoliang Su

Role of the Hypoxia-inducible factor-1 alpha induced autophagy in the conversion of non-stem pancreatic cancer cells into CD133+ pancreatic cancer stem-like cells.

The initiation and progression of various solid tumors, including pancreatic carcinoma, are driven by a population of cells with stem cell properties, namely cancer stem cells (CSCs). Like their normal counterparts, CSCs are also believed to rely on their own microenvironment termed niches to sustain the population. Hypoxia-inducible factor-1α (HIF-1α) is a major actor in the cell survival response to hypoxia. Recently, several researchers proposed that non-stem cancer cells can convert to stem-like cells to maintain equilibrium. The present study focuses on whether non-stem pancreatic cancer cells can convert to stem-like cells and the role of HIF-1α and autophagy in modulating this conversation. The non-stem pancreatic cancer cells and pancreatic cancer stem-like cells were separated by magnetic sorting column. Intermittent hypoxia enhanced stem-like properties of non-stem pancreatic cancer cells and stimulated the levels of HIF-1α, LC3-II and Beclin. Enhanced autophagy was associated with the elevated level of HIF-1α. The conversation of non-stem pancreatic cancer cells into pancreatic cancer stem-like cells was induced by HIF-1α and autophagy. This novel finding may indicate the specific role of HIF-1α and autophagy in promoting the dynamic equilibrium between CSCs and non-CSCs. Also, it emphasizes the importance of developing therapeutic strategies targeting cancer stem cells as well as the microenvironmental influence on the tumor.

HMGB1 blockade attenuates experimental autoimmune myocarditis and suppresses Th17-cell expansion

High‐mobility group box 1 (HMGB1), a non‐histone nuclear protein, has been implicated in cardiovascular diseases. Dilated cardiomyopathy (DCM), one of the leading causes of heart failure, is often caused by coxsackievirus B3‐triggered myocarditis and promoted by the post‐infectious autoimmune process. Th17 cells, a novel CD4+ T subset, may be important in the pathogenesis of autoimmune myocarditis. In the present study, we attempted to block HMGB1 function with a monoclonal antibody specific for HMGB1 B box and investigated the effects of the blockade on Th17 cells and experimental autoimmune myocarditis (EAM). After induction of EAM, HMGB1 protein levels were significantly elevated both in the heart and blood. Administration of an anti‐HMGB1 B box mAb attenuated cardiac pathological changes and reduced the number of infiltrating inflammatory cells in the heart during EAM. These protective effects of HMGB1 blockade correlated with a reduced number of Th17 cells in local tissues and lower levels of IL‐17 in the serum. Furthermore, in vitro, studies demonstrated that HMGB1 promoted Th17‐cell expansion. Therefore, we speculate that HMGB1 blockade ameliorates cardiac pathological changes in EAM by suppressing Th17 cells.

Differentiation Imbalance of Th1/ Th17 in Peripheral Blood Mononuclear Cells Might Contribute to Pathogenesis of Hashimoto’s Thyroiditis

T helper 17(Th17) cell is a new subset of CD4+ T cells that produce a proinflammatory cytokine interleukin‐17 (IL‐17). Th17 cells have recently been shown to play a critical role in many autoimmune diseases that had previously been thought to be Th1 dominant. Although Hashimoto’s thyroiditis (HT) was thought to be a Th1‐type disease, the contributions of Th17 cells to the pathogenesis remain unclear. In this study, we investigated the expression levels of Th1/Th17 cell‐associated factors in peripheral blood mononuclear cells (PBMC) and plasma from patients with HT by quantitative real‐time polymerase chain reaction (RT‐qPCR) and enzyme‐linked immunosorbent assay (ELISA). Our results showed that the expression levels of Th1 cells‐related T‐bet and interferon‐γ (IFN‐γ) mRNA in PBMC from HT significantly decreased. However, the mRNA of Th17 coherent retinoic acid‐related orphan nuclear receptor gamma t (RORγt) and IL‐17 in patients with HT increased. In addition, a negative correlation between T‐bet and RORγt mRNA expression was found in patients with HT, and the similar phenomena also appeared on the levels of mRNA and plasma concentration between IFN‐γ and IL‐17. It suggested that Th17 cells rather than Th1 cells predominated among patients suffering from HT, and Th17 cells might be involved in the pathogenesis of HT.

Upregulation of autophagy by hypoxia-inducible factor-1α promotes EMT and metastatic ability of CD133+ pancreatic cancer stem-like cells during intermittent hypoxia

Epithelial-to-mesenchymal transition (EMT) facilitates the escape of pancreatic cancer cells from the primary tumor site, which is a key early event in metastasis. In the present study, we examined if intermittent hypoxia facilitates the invasiveness of human pancreatic cancer cell lines (Panc-1 and BxPC-3) by Transwell assay. We used western blotting and flow cytometry analysis to quantify stem-like cells in the migratory cells during intermittent hypoxia in the human pancreatic cancer cells. Under normoxia or intermittent hypoxia, the expression of autophagy-related proteins (LC3-II and Beclin), hypoxia-inducible factor-1α (HIF-1α) and EMT-related markers (E-cadherin, Vimentin and N-cadherin) was examined by western blotting. siRNA and the autophagic inhibitor were used to access the role of HIF-1α and autophagy in promoting metastasis and EMT. Under intermittent hypoxia, pancreatic cancer cells demonstrated enhanced invasive ability and enriched stem-like cells. The migratory cells displayed stem-like cell characteristics and elevated the expression of LC3-II and Beclin-1, HIF-1α, E-cadherin, Vimentin and N-cadherin under intermittent hypoxia conditions. Moreover, enhanced autophagy was induced by the elevated level of HIF-1α. The metastatic ability and EMT of pancreatic cancer stem cells was associated with HIF-1α and autophagy. This novel finding may indicate the specific role of HIF-1α and autophagy in promoting the metastatic ability of pancreatic cancer stem cells. Additionally, it emphasizes the importance of developing therapeutic strategies targeting cancer stem cells and autophagy to reduce metastasis.

Enhanced HMGB1 Expression May Contribute to Th17 Cells Activation in Rheumatoid Arthritis

Rheumatoid arthritis(RA) is a common autoimmune disease associated with Th17 cells, but what about the effect of high-mobility group box chromosomal protein 1 (HMGB1) and the relationship between Th17-associated factors and HMGB1 in RA remains unknown. In the present study, we investigated the mRNA levels of HMGB1, RORγt, and IL-17 in peripheral blood mononuclear cells (PBMCs) from patients with rheumatoid arthritis by quantitative real-time PCR (RT-qPCR), and the concentrations of HMGB1, IL-17, and IL-23 in plasma were detected by ELISA. And then, the effect of HMGB1 on Th17 cells differentiation was analyzed in vitro. Our clinical studies showed that the mRNAs of HMGB1, RORγt, and IL-17 in patients were higher than that in health control (P < 0.05), especially in active RA patients (P < 0.05). The plasma HMGB1, IL-17, and IL-23 in RA patients were also higher than that in health control (P < 0.05); there was a positive correlation between the expression levels of HMGB1 and the amount of CRP, ERS, and RF in plasma. In vitro, the IL-17-produced CD4+T cells were increased with 100 ng/mL rHMGB1 for 12h, which indicated that the increased HMGB1 might contribute to Th17 cells activation in RA patients.

Identification and characterization of class 1 integrons among Pseudomonas aeruginosa isolates from patients in Zhenjiang, China.

OBJECTIVES The role of integrons in the spread of antibiotic resistance has been well established. The aim of this study was to investigate the resistance profiles of Pseudomonas aeruginosa isolated from patients in Zhenjiang to 13 antibiotics, and to identify the structure and dissemination of class 1 integrons. METHODS The Kirby-Bauer disk diffusion assay was used to determine the rate of P. aeruginosa resistance. Class 1 integrons from multidrug-resistant isolates were amplified by PCR, and their PCR products were sequenced. We also analyzed the integron structures containing the same gene cassettes by restriction fragment length polymorphism (RFLP). Isolates were genotyped by pulsed-field gel electrophoresis (PFGE). RESULTS The resistance rates were between 29.6% and 90.1%. The prevalence of class 1 integrons was 38.0%. These integrons included five gene cassettes (aadB, aac6-II, blaPSE-1, dfrA17, and aadA5). The dfrA17 and aadA5 gene cassettes were found most often. CONCLUSIONS Class 1 integrons were found to be widespread in P. aeruginosa isolated from clinical samples in the Zhenjiang area of China. The antibiotic resistance rates in class 1 integron-positive strains of P. aeruginosa were noticeably higher than those in class 1 integron-negative strains. PFGE showed that particular clones were circulating among patients.

HMGB1 Promotes the Differentiation of Th17 via Up-Regulating TLR2 and IL-23 of CD14+ Monocytes from Patients with Rheumatoid Arthritis

High‐mobility group box 1 (HMGB1) is a non‐histone nuclear protein that is released extracellulary and has been implicated in autoimmune disease. Toll‐like receptor 2 (TLR2) signalling is thought to be essential for the inflammatory response and for immune disorders. In recent studies, enhanced HMGB1 and TLR2 expressions have been found in rheumatoid arthritis (RA), respectively. The aim of this study is to explore whether HMGB1 stimulation can up‐regulate the expression of TLR2 on CD14+ monocytes from patients with RA and to clarify the subsequent events involving Th17 cells and Th17 cell‐associated cytokine changes. Our results showed that the frequency of CD14+ cells in peripheral blood mononuclear cell (PBMC) was obviously increased, and enhanced expression of TLR2 on CD14+ monocytes was also found in patients with RA, compared with healthy controls with statistical significance (P < 0.001). In addition, the levels of IL‐17, IL‐23 and IL‐6 in supernatants from cultured monocytes from patients and in patient’s plasma were increased, and NF‐κB, the downstream target of TLR2, also showed a marked elevation after monocytes were stimulated by HMGB1. This implies that the enhanced TLR2 pathway and Th17 cell polarization may be due to HMGB1 stimulation in rheumatoid arthritis.

RETRACTED: CD133+/CD44+/Oct4+/Nestin+ stem-like cells isolated from Panc-1 cell line may contribute to multi-resistance and metastasis of pancreatic cancer

Pancreatic cancer is an aggressive malignant disease. Owing to the lack of early symptoms, accompanied by extensive metastasis and high resistance to chemotherapy, pancreatic adenocarcinoma becomes the fourth leading cause of cancer-related deaths. In this study, we identified a subpopulation of cells isolated from the Panc-1 cell line and named pancreatic cancer stem-like cells. These Panc-1 stem-like cells expressed high levels of CD133/CD44/Oct4/Nestin. Compared to Panc-1 cells, Panc-1 stem-like cells were resistant to gemcitabine and expressed high levels of MDR1; furthermore, Panc-1 stem-like cells have high anti-apoptotic, but weak proliferative potential. These results indicated that Panc-1 stem-like cells, as a novel group, may be a potential major cause of pancreatic cancer multidrug resistance and extensive metastasis.

Polarization of ILC2s in Peripheral Blood Might Contribute to Immunosuppressive Microenvironment in Patients with Gastric Cancer

Newly identified nuocytes or group 2 innate lymphoid cells (ILC2s) play an important role in Th2 cell mediated immunity such as protective immune responses to helminth parasites, allergic asthma, and chronic rhinosinusitis. However, the contributions of ILC2s in the occurrence and development of cancer remain unknown. Our previous study found that there was a predominant Th2 phenotype in patients with gastric cancer. In this study, the ILC2s related genes or molecules in PBMC from patients with gastric cancer were measured, and the potential correlation between them was analyzed. The expression levels of RORα, GATA3, T1/ST2, IL-17RB, CRTH2, IL-33, IL-5, and IL-4 mRNA were significantly increased in patients, but no significant changes were found in ICOS, CD45, and IL-13 expression, and there was a positive correlation between RORα or IL-13 and other related factors, such as ICOS and CD45. The increased frequency of ILC2s was also found in PBMC of patients by flow cytometry. In addition, the mRNA of Arg1 and iNOS were also significantly increased in patients. These results suggested that there are polarized ILC2s in gastric cancer patients which might contribute to immunosuppressive microenvironment and closely related to the upregulation of MDSCs and M2 macrophages.

Infiltration of Alternatively Activated Macrophages in Cancer Tissue Is Associated with MDSC and Th2 Polarization in Patients with Esophageal Cancer

Myeloid derived suppressor cells (MDSCs) expand in cancer bearing hosts and contribute to tumor immune evasion. M2 macrophages constitute a major cellular component of cancer-related inflammation. However, the correlation between circulating MDSCs and infiltrating M2 macrophages in tumor tissues from patients with esophageal cancer (ECA), and its potential relationship with the polarization of Th2 cells remain unclear. In the present study, we showed the level of MDSCs in PBMC and Arg1 in plasma were significantly elevated in ECA patients, and the increased ratio of MDSC in PBMC was closely related to the expression of CD163 in cancer tissues. In addition, the ECA patients exhibited remarkable increases in the mRNA levels of IL-4 and GATA3, as well as the protein levels of IL-13 and IL-6, but IFN-γ and IL-12 in peripheral blood were decreased. Our data indicate that the increased Th2 cytokines are associated with MDSCs and M2 macrophages polarization, and foster the infiltration of CD163+M2 macrophages in cancer tissues, which promote the formation of immunosuppressive microenvironment in ECA patients.