Hypoxia is a common feature of many solid tumors, including hepatocellular carcinoma (HCC). Hypoxia can promote tumor progression and induce radiation and chemotherapy resistance. As one of the major mediators of hypoxic response, hypoxia inducible factor-1 (HIF-1) has been shown to activate hypoxia-responsive genes, which are involved in multiple aspects of tumorigenesis and cancer progression, including proliferation, metabolism, angiogenesis, invasion, metastasis and therapy resistance. It has been demonstrated that a high level of HIF-1 in the HCC microenvironment leads to enhanced proliferation and survival of HCC cells. Accordingly, overexpression, of HIF-1 is associated with poor prognosis in HCC. In this review, we described the mechanism by which HIF-1 is regulated and how HIF-1 mediates the biological effects of hypoxia in tissues. We also summarized the latest findings concerning the role of HIF-1 in the development of HCC, which could shed light on new therapeutic approaches for the treatment of HCC.
BackgroundExosomes are carriers of intercellular information and regulate the tumor microenvironment. They play an important role in drug resistance by transporting RNA molecules and proteins. However, their effects on sorafenib resistance in hepatocellular carcinoma (HCC) are not completely understood.MethodsExosomes were isolated from two invasive hepatoma cell lines (MHCC-97 L and MHCC-97H), and their roles in regulating sorafenib resistance in liver cancer cells as well as the underlying molecular mechanisms were determined. The exosomes were analyzed by TEM (transmission electron microscopy), DLS (dynamic light scattering) and Western blotting. Cell viability, cell death and the effects of exosomes on the HGF/c-Met/Akt signaling pathway in cancer cells were analyzed by MTT assays, FACS analysis and Western blotting, respectively. Moreover, the effects of exosomes on sorafenib resistance in vivo were investigated using a subcutaneous transplantation tumor model in athymic nude mice.ResultsExosomes derived from HCC cells were of the expected size and expressed the exosomal markers CD9 and CD63. They induced sorafenib resistance in vitro by activating the HGF/c-Met/Akt signaling pathway and inhibiting sorafenib-induced apoptosis. They also induced sorafenib resistance in vivo by inhibiting sorafenib-induced apoptosis. Moreover, exosomes derived from highly invasive tumor cells had greater efficacy than that of exosomes derived from less invasive cells.ConclusionsThese data reveal the important role of HCC cell-derived exosomes in the drug resistance of liver cancer cells and demonstrate the intrinsic interaction between exosomes and their targeted tumor cells. This study suggests a new strategy for improving the effectiveness of sorafenib in treating HCC.
MicroRNA-155 is a candidate oncogenic microRNA and plays an important role in promoting HCC cells invasion. Our findings suggest that microRNA-155 may serve as a novel biomarker for tumor recurrence and survival of HCC patients following OLT.
Mechanical properties of hydrogels are critical for their applications as articular cartilage regeneration scaffolds, because they provide not only the mechanical support, but also the mechanical cues essential to maintain the phenotype of cartilage‐forming cells. Inspired by the microscopic architecture of natural cartilage, here the engineering of a novel double‐network hydrogel with interconnected polymer‐supramolecular polymer double‐network (PS‐DN gel) for cartilage regeneration is reported. The polymer network is made of polyacrylamide and the supramolecular polymer network comprises of a kind of self‐assembled peptide fibers. Upon mechanical loading, the peptide fibers serve as sacrificial bonds to efficiently dissipate energy. They can quickly reform when mechanical load is released thanks to the fast and accurate peptide self‐assembly. These entail the PS‐DN gel of high mechanical strength of ≈0.32–0.57 MPa, fracture energy of ≈300–2670 J m−2, compressibility of ≈66%–90%, and fast recovery in seconds. The gel also shows significant energy dissipation, strain stiffening, and stress relaxation behaviors similar to articular cartilage. Moreover, the mechanical properties of the PS‐DN gel can be tailored by adjusting the chemical components of the gel. Therefore, this novel biomaterial represents a promising candidate for the regeneration of cartilage and other load bearing tissues.
Recurrence Prognosis Liver transplantation A B S T R A C TTumor recurrence-related microRNAs (miRNAs) in hepatocellular carcinoma (HCC) following orthotopic liver transplantation (OLT) are not clear yet. This study was designed to determine whether altered miRNA expression is associated with HCC recurrence and prognosis following OLT. 18 miRNAs, including 6 up-regulated and 12 down-regulated miRNAs were identified by microarray in primary HCC samples of patients who had developed HCC recurrence (n ¼ 5) compared to those with non-recurrence (n ¼ 5) following OLT by using p < 0.05 as cutoff value. The six most significantly altered miRNAs (fold change ! 2: miR-19a, miR-886-5p, miR-126, miR-223, miR-24 and miR-147) were further confirmed by qRT-PCR in the remaining 105 HCC samples. In receiver-operating characteristic curve analysis, this six miRNAs were of high sensitivity and specificity in predicting HCC recurrence. Using Cox regression and risk score analysis, we built a six-miRNA signature based on their qRT-PCR readings for the prediction of outcome of HCC following OLT. KaplaneMeier and Cox proportional regression revealed this six-miRNA signature was a significant independent predictor of overall survival (log-rank p ¼ 0.020) and recurrence-free survival (log-rank p < 0.001). Finally, the data were further reconfirmed in an independent cohort of 50 patients from another transplant center. In addition, bioinformatics Gene Ontology and pathway analysis were also performed to better understand the critical roles of these miRNAs in HCC recurrence. Our study, in addition to suggesting a different miRNA expression pattern between HCC samples of patients with recurrence and those with non-recurrence, proposes that this six-miRNA signature may serve as biomarker for prognosis of HCC patients following OLT.
It has been shown that long noncoding RNAs (lncRNAs) play a critical role in the regulation of cellular processes including cancer progression and metastasis. However, the biological functions and clinical significance of lncRNA AFAP1-AS1 in hepatocellular carcinoma (HCC) remain unclear. Expression of AFAP1-AS1 was analyzed in 78 HCC tissues by real-time PCR. The effect of AFAP1-AS1 on cell proliferation was examined by MTT assay, cell apoptosis was detected by flow cytometric analysis and cell invasion was determined by Transwell assay. RhoA/Rac2 signaling and downstream factors were verified by western blotting. HCC cells infected with si-AFAP1-AS1 were injected into nude mice to investigate the effect of AFAP1-AS1 on the tumorigenesis in vivo. We found that increased expression of AFAP1-AS1 was significantly correlated with pathological staging (P=0.024) and lymph-vascular space invasion (LVSI) in HCC patients (P=0.007). Multivariate analyses indicated that AFAP1-AS1 represented an independent predictor for overall survival of HCC (P=0.029). Further experiments showed that knockdown of AFAP1-AS1 by si-AFAP1-AS1 decreased the proliferation and invasion in vitro and in vivo, induced cell apoptosis and blocked cell cycle in S phase via inhibition of the RhoA/Rac2 signaling. Taken together, our findings indicate that AFAP1-AS1 may promote the HCC development through upregulation of RhoA/Rac2 signaling and provide a potential therapeutic target for HCC.
Temporomandibular disorders (TMD) are a group of clinical problems affecting temporomandibular joint (TMJ), myofascial muscles and other related structures. Splint therapy is the most commonly used approach to treatment of TMD, but its effectiveness is remains unclear. We therefore conducted a meta-analysis to evaluate the effectiveness of splint therapy for TMD in adults. The electronic databases PubMed, EMBASE, Cochrane Library, and ClinicalTrials.gov were searched for reports published up to March 31, 2016. Thirteen eligible studies involving 538 patients were identified. The results indicated that splint therapy increased maximal mouth opening (MMO) for patients with a MMO <45mm and reduced pain intensity measured using the visual analogue scale (VAS) for patients with TMD without specific description (TMDSD). Splint therapy also reduced the frequency of painful episodes for patients with TMJ clicking. No publication bias was observed, as determined with Egger's test for all outcomes. On the basis of this evidence, we recommend the use of splints for the treatment and control of TMD in adults.
As a further step towards the modernization of acupuncture, the objective of this review was to figure out the frequency and severity of adverse complications and events in acupuncture treatment reported from 1980 to 2013 in China. All first-hand case reports of acupuncture-related complications and adverse events that could be identified in the scientific literature were reviewed and classified according to the type of complication and adverse event, circumstance of the event, and long-term patient outcome. The selected case reports were published between 1980 and 2013 in 3 databases. Relevant papers were collected and analyzed by 2 reviewers. Over the 33 years, 182 incidents were identified in 133 relevant papers. Internal organ, tissue, or nerve injury is the main complications of acupuncture especially for pneumothorax and central nervous system injury. Adverse effects also included syncope, infections, hemorrhage, allergy, burn, aphonia, hysteria, cough, thirst, fever, somnolence, and broken needles. Qualifying training of acupuncturists should be systemized and the clinical acupuncture operations should be standardized in order to effectively prevent the occurrence of acupuncture accidents, enhance the influence of acupuncture, and further popularize acupuncture to the rest of the world.
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