Huiling Shen

miR-145 sensitizes ovarian cancer cells to paclitaxel by targeting Sp1 and Cdk6.

Multidrug resistance (MDR) remains a major obstacle to effective chemotherapy treatment in ovarian cancer. In our study, paclitaxel‐resistant ovarian cancer patients and cell lines had decreased miR‐145 levels and expressed high levels of Sp1 and Cdk6. Introducing miR‐145 into SKOV3/PTX and A2780/PTX cells led to a reduction in Cdk6 and Sp1 along with downregulation of P‐gp and pRb. These changes resulted in increased accumulation of antineoplastic drugs and G1 cell cycle arrest, which rendered the cells more sensitive to paclitaxel in vitro and in vivo. These effects could be reversed by reintroducing Sp1 or Cdk6 into cells expressing high levels of miR‐145, resulting in restoration of P‐gp and pRb levels. Furthermore, we confirmed that both Cdk6 and Sp1 are targets of miR‐145. Intriguingly, demethylation with 5‐aza‐dC led to reactivation of miR‐145 expression in drug‐resistant ovarian cancer cell lines, which also resulted in increased sensitivity to paclitaxel. Collectively, these findings begin to elucidate the role of miR‐145 as an important regulator of chemoresistance in ovarian cancer by controlling both Cdk6 and Sp1.

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.

Th17 cell expansion in gastric cancer may contribute to cancer development and metastasis

Th0 cells differentiate into Th1 or Th2 depending on multiple transcription factors acting on specific time points to regulate gene expression. Th17 cells, a subset of IL-17-producing T cells distinct from Th1 or Th2 cells has been described as key players in inflammation and autoimmune diseases as well as cancer development. In the present study, 66 patients with gastric cancer were included; the expression level of Th1- and Th17-related IFN-γ, IL-17, T-bet, RORγt in gastric cancer tissues and peripheral blood mononuclear cell (PBMC) were detected, analyzed the relationship between Th17 or Th1 infiltration and metastasis and explored the possible mechanism. Our results showed that IL-17 and RORγt expression were significantly increased in gastric cancer tissues and PBMC, especially, in metastasis patients; plasma IL-17 also increased; furthermore, the mRNA and protein levels of IL-1β, IL-21 and TGF-β were up-regulated. All the data indicated that Th17 was infiltrated the cancer tissue; IL-1β, IL-21 and TGF-β were also involved in gastric cancer development by promoting Th17 cell generation. From the above data, we speculated that Th17 cell expansion in gastric cancer may contribute to cancer development and metastasis.

HMGB1 Facilitated Macrophage Reprogramming towards a Proinflammatory M1-like Phenotype in Experimental Autoimmune Myocarditis Development

Macrophages can be reprogramming, such as the classical activated macrophage, M1 or alternative activated macrophages, M2 phenotype following the milieu danger signals, especially inflammatory factors. Macrophage reprogramming is now considered as a key determinant of disease development and/or regression. Experimental autoimmune myocarditis (EAM) is characterized by monocytes/macrophage infiltration, Th17 cells activation and inflammatory factors producing such as high mobility group box 1 (HMGB1). Whether infiltrated macrophages could be reprogramming in EAM? HMGB1 was associated with macrophage reprogramming? Our results clearly demonstrated that infiltrated macrophage was reprogrammed towards a proinflammatory M1-like phenotype and cardiac protection by monocytes/macrophages depletion or HMGB1 blockade in EAM; in vitro, HMGB1 facilitated macrophage reprogramming towards M1-like phenotype dependent on TLR4-PI3Kγ-Erk1/2 pathway; furthermore, the reprogramming M1-like macrophage promoted Th17 expansion. Therefore, we speculated that HMGB1 contributed EAM development via facilitating macrophage reprogramming towards M1-like phenotype except for directly modulating Th17 cells expansion.

Up-regulated HMGB1 in EAM directly led to collagen deposition by a PKCβ/Erk1/2-dependent pathway: cardiac fibroblast/myofibroblast might be another source of HMGB1.

High mobility group box 1 (HMGB1), an important inflammatory mediator, is actively secreted by immune cells and some non‐immune cells or passively released by necrotic cells. HMGB1 has been implicated in many inflammatory diseases. Our previous published data demonstrated that HMGB1 was up‐regulated in heart tissue or serum in experimental autoimmune myocarditis (EAM); HMGB1 blockade could ameliorate cardiac fibrosis at the last stage of EAM. And yet, until now, no data directly showed that HMGB1 was associated with cardiac fibrosis. Therefore, the aims of the present work were to assess whether (1) up‐regulated HMGB1 could directly lead to cardiac fibrosis in EAM; (2) cardiac fibroblast/myofibroblasts could secrete HMGB1 as another source of high‐level HMGB1 in EAM; and (3) HMGB1 blockade could effectively prevent cardiac fibrosis at the last stage of EAM. Our results clearly demonstrated that HMGB1 could directly lead to cardiac collagen deposition, which was associated with PKCβ/Erk1/2 signalling pathway; furthermore, cardiac fibroblast/myofibroblasts could actively secrete HMGB1 under external stress; and HMGB1 secreted by cardiac fibroblasts/myofibroblasts led to cardiac fibrosis via PKCβ activation by autocrine means; HMGB1 blockade could efficiently ameliorate cardiac fibrosis in EAM mice.

Exogenous High‐Mobility Group Box 1 Inhibits Apoptosis and Promotes the Proliferation of Lewis Cells via RAGE/TLR4‐Dependent Signal Pathways

Upregulated high‐mobility group box 1 (HMGB1) has been found in many diseases. Nevertheless, the function of HMGB1 on modulating the proliferation of lung cancer cells (Lewis cells) and inhibiting apoptosis is poorly understood, as well as the involved intracellular signalling. In the present study, we firstly found the apoptosis of Lewis was increased following Hanks’ balanced salt solution (HBSS)‐induced starvation, while it was rescued after exogenous HMGB1 protein was added; furthermore, the receptor for advanced glycation end products (RAGE) and Toll‐like receptor (TLR4) could coordinately improve the proliferation of tumour cells in vitro, and HMGB1 could enhance the phosphorylation of PI3K/Akt and Erk1/2, inhibit the expression of pro‐apoptosis protein Bax and promote the expression of anti‐apoptosis protein Bcl‐2. These findings clearly demonstrated that HMGB1–RAGE/TLR4‐ PI3K‐Akt/Erk1/2 pathway contributed to the proliferation of Lewis. Moreover, our observations provide experimental and theoretical basis for clinical biological therapy for cancers; it also may be a new target for intervention and treatment of lung cancer.

IL-6R/STAT3/miR-204 feedback loop contributes to cisplatin resistance of epithelial ovarian cancer cells

Enhanced chemoresistance is, among other factors, believed to be responsible for treatment failure and tumor relapse in patients with epithelial ovarian cancer (EOC). Here, we exposed EOC cells to interleukin-6 (IL-6) to activate oncogenic STAT3, which directly repressed miR-204 via a conserved STAT3-binding site near the TRPM3 promoter region upstream of miR-204. Repression of miR-204 was required for IL-6-induced cisplatin (cDDP) resistance. Furthermore, we identified the IL-6 receptor (IL-6R), which mediates IL-6-dependent STAT3 activation, as a direct miR-204 target. Importantly, the resulting IL-6R/STAT3/miR-204 feedback loop was identified in patients with EOC, and its activity correlated with chemosensitivity. Moreover, exogenous miR-204 blocked this circuit and enhanced cDDP sensitivity both in vitro and in vivo by inactivating IL-6R/STAT3 signaling and subsequently decreasing the expression of anti-apoptotic proteins. Our findings illustrate the function of this feedback loop in cDDP-based therapy and may offer a broadly useful approach to improve EOC therapy.

HMGB1 modulates Lewis cell autophagy and promotes cell survival via RAGE-HMGB1-Erk1/2 positive feedback during nutrient depletion.

Autophagy is a self-digesting mechanism responsible for the removal of long-lived proteins and damaged organelles by lysosomes. It also allows cells to survive during nutrient depletion and/or in the absence of growth factors. High-mobility group protein 1 (HMGB1) is a highly-conserved nuclear protein that has been associated with cell autophagy; however, the mechanisms responsible for this role remain unclear. Many reports have demonstrated that autophagy represents a survival strategy for tumor cells during nutrient depletion, oxidative stress and DNA damage. In the present study, we explored the mechanisms whereby HMGB1 regulates tumor cell autophagy during nutrient depletion (the cells were cultured in Hanks balanced salt solution, HBSS). HMGB1 expression in Lewis cells increased and the protein was shuttled from the nucleus to the cytoplasm and was secreted, coincident with up-regulation of autophagy. Prevention of HMGB1 binding to the receptor for advanced glycation end products (RAGE) or knock-down of HMGB1 expression led to inhibition of autophagy and increased apoptosis. These results demonstrated a positive feedback pathway whereby starvation of Lewis cells promoted HMGB1 secretion, allowing cells to survive by regulating autophagy via a RAGE-HMGB1-extracellular signal-regulated kinase1/2-dependent pathway. These results also implicate HMGB1 as a potential risk factor for cancer growth and metastasis.

IFN-γ-producing Th17 cells bias by HMGB1-T-bet/RUNX3 axis might contribute to progression of coronary artery atherosclerosis.

BACKGROUNDnIFN-γ-producing Th17 cells have been implicated in autoimmune disorders, but their properties in humans are known only partially. The molecular mechanisms and external factors that govern IFN-γ-producing Th17-cell bias are incompletely understood. The present work was to clarify whether (i) IFN-γ-producing Th17 cells are present in the peripheral circulation of patients with coronary atherosclerosis (CA); (ii) high mobility group box (HMGB)1 in circulation is associated with IFN-γ-producing Th17-cell bias.nnnMETHODSnThirty-six patients (17 females and 19 males; 45-84 years) diagnosed as having atherosclerosis after coronary angiography for suspected or known CA were included the study cohort. Samples of peripheral blood were collected from healthy volunteers and patients, and classical tests (flow cytometry, RT-qPCR) were used to measure blood components.nnnRESULTS AND CONCLUSIONnOur results clearly demonstrated that HMGB1 were up-regulated in different progressive CA patients: 5.38xa0±xa01.48xa0ng/ml, 6.30xa0±xa01.53xa0ng/ml and 5.86xa0±xa01.12xa0ng/ml vs1.45xa0±xa00.65xa0ng/ml for only atherosclerotic plaque (AP), atherosclerotic plaque and some plaque rupture, no thrombosis (PR), plaque rupture and accompanying thrombosis (TH) and volunteers, respectively, pxa0<xa00.05. The frequency of IFN-γ-producing Th17xa0cells was 2.33xa0±xa00.58%, 1.93xa0±xa00.2% and 2.21xa0±xa00.65% vs 0.38xa0±xa00.21% for AP, PR, TH and volunteers, pxa0<xa00.05, respectively. Furthermore, HMGB1 contributed to IFN-γ-producing Th17-cell bias by controlling expression of T-bet and RUNX3. We demonstrated, for the first time, that HMGB1 is a potential inducer of IFN-γ-producing Th17-cell bias, and that IFN-γ-producing Th17xa0cells might be one of the pathogenic factors in atherosclerosis.

A method of experimental rheumatoid arthritis induction using collagen type II isolated from chicken sternal cartilage

At present, collagen‑induced arthritis (CIA) is the best known and most extensively used model for the immunological and pathological characteristics of human rheumatoid arthritis (RA). This model is useful not only in aiding our understanding of the pathogenesis of this disease, but also in the development of new therapies. Bovine, porcine and human collagen has been used to induce CIA; however, response has been identified to vary between strains and injection conditions, and false positive results and reduced potency are common as a result of minor contaminants or deglycosylated protein. Therefore, in the present study, typexa0II collagen (CII) was isolated and purified from chicken sternal cartilage and was found to successfully induce the RA model. Furthermore, Txa0helperxa017 (Th17) cells were observed to infiltrate the joint on day 45 following induction by CII. Inxa0vitro, expression of toll‑like receptor 2 (TLR2) increased in peritoneal macrophages stimulated by CII. In addition, blockage of TLR2 was identified to markedly decrease levels of TGF‑β and IL‑6 in the cell culture supernatant. The results indicate that CII isolated from chicken sternal cartilage may be recognized by TLR2 on macrophages, leading to TGF‑β and IL‑6 production and subsequent activation of Th17 cells which mediates CIA development.