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Background: Accumulating evidence shows that, the dysregulation of circular RNAs (circRNAs) is associated with the progression of multiple malignancies. But, the underlying mechanisms by which has_circ_0032627 (circDLST) contributed to gastric cancer (GC) remain undocumented. Methods: The expression and cellular localization of circDLST and its association with clinicopathological characteristics and prognosis in patients with GC was analysed by using fluorescence in situ hybridization. Gain- and loss-of-function experiments as well as a subcutaneous xenograft tumor model and a liver metastasis model from orthotopic implantation of GC tissues were conducted to assess the role of circDLST in GC cells. CircDLST specific binding with miR-502-5p was confirmed by dual luciferase gene report, RNA immunoprecipitation (RIP) assays and RIP-miRNA expression profiling. qRT-PCR and Western blot analysis was used to detect the effects of circDLST on miR-502-5p-mediated NRAS/MEK1/ERK1/2 signaling in GC cells. Results: The expression levels of circDLST were dramatically elevated in GC tissues as compared with the adjacent normal tissues, and acted as an independent prognostic factor of poor survival in patients with GC. Knockdown of circDLST inhibited the cell viability, colony formation, DNA synthesis, cell invasion and liver metastasis in vitro and in vivo, whereas overexpression of circDLST had the opposite effects. Furthermore, circDLST was co-localized with miR-502-5p in the cytoplasm of GC cells, and acted as a sponge of miR-502-3p in GC cells, which abrogated the tumor promoting effects of circDLST by inactivating the NRAS/MEK1/ERK1/2 signaling in GC cells. Conclusion: CircDLST promotes the tumorigenesis and metastasis of GC cells by sponging miR-502-5p to activate the NRAS/MEK1/ERK1/2 signaling. [ABSTRACT FROM AUTHOR]

Background: Cancer metastasis is determined by the formation of the metastatic niche and the ability of cancer cells to adapt to microenvironmental stresses. Anoikis resistance is a fundamental feature of metastatic cancer cell survival during metastatic cancer progression. However, the mechanisms underlying anoikis resistance in ovarian cancer are still unclear., Methods: Expressions of miRNA-141 and its downstream targets were evaluated by qPCR, Western blotting, Immunohistochemical (IHC) and in situ hybridization (ISH) assays. The luciferase assays were used to prove KLF12 as the downstream target of miR-141. The cDNA microarray and apoptotic protein arrays were used to identify the targets of miR-141 and KLF12. The competition of KLF12 and Sp1 on survivin promoter was examined by ChIP assay. IHC analysis on ovarian cancer tissue array was used to evaluate the expressions of KLF12 and miR-141 and to show the clinical relevance. The functional studies were performed by in vitro and in vivo tumorigenic assays., Results: Enforced expression of miR-141 promotes, while knockdown of miR-141 expression inhibits, cell proliferation, anchorage-independent capacity, anoikis resistance, tumor growth and peritoneal metastases of ovarian cancer cells. Bioinformatics and functional analysis identified that Kruppel-related zinc finger protein AP-2rep (KLF12) is directly targeted by miR-141. Consistent with this finding, knockdown of KLF12 phenocopied the effects of miR-141 overexpression in ovarian cancer cells. In contrast, restoration of KLF12 in miR-141-expressing cells significantly attenuated anoikis resistance in ovarian cancer cells via interfering with Sp1-mediated survivin transcription, which inhibits the intrinsic apoptotic pathway and is crucial for ovarian cancer cell survival, anoikis resistance and peritoneal metastases. Immunohistochemical (IHC) and in situ hybridization (ISH) assays confirmed that miRNA-141 expression is inversely correlated with KLF12 expression and significantly associated with advanced ovarian cancers accompanied with distal metastases, underscoring the clinical relevance of our findings., Conclusions: Our data identify a novel signaling axis of miR-141/KLF12/Sp1/survivin in enhancing anoikis resistance and likely serves as a potential therapeutic target for metastatic ovarian cancer.

Background: Studies have come to conflicting conclusions about whether adiponectin (APN) expression is associated with cancer prognosis. To help resolve this question, we meta-analyzed the available evidence., Methods: PubMed, EMBASE, the Cochrane Library, the Chinese Biological Medical Database and the Chinese National Knowledge Infrastructure Database were systematically searched to identify all eligible studies examining APN expression and prognosis for patients with any type of cancer. Pooled hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) related to overall survival (OS) or disease-free survival (DFS) were calculated., Results: Ten studies involving 999 patients were meta-analyzed. Analysis across all patients revealed no significant association between high/positive APN expression and DFS, but they did show a significant association between high/positive APN expression and OS (HR 1.51, 95 %CI 1.21 to 1.89). Subgroup analysis showed that high/positive APN expression in non-Asians was significantly associated with both DFS (HR 1.36, 95% CI 1.03 to 1.80) and OS (HR 1.53, 95 %CI 1.20 to 1.96), but no such associations were observed in Asians. In addition, high/positive APN expression was significantly associated with OS across all patients with hepatocellular carcinoma (HR 1.89, 95 %CI 1.20 to 2.98)., Conclusions: The available evidence suggests that high/positive APN expression is associated with poor prognosis for patients with various carcinomas, especially for non-Asian cancer patients and for all patients with hepatocellular carcinoma. These findings should be confirmed and extended in large, well-designed studies.

Background: The novel gene HA117 is a multidrug resistance (MDR) gene expressed by all-trans retinoic acid-resistant HL-60 cells. In the present study, we compared the multidrug resistance of the HA117 with that of the classical multidrug resistance gene 1 (MDR1) in breast cancer cell line 4T1., Methods: Transduction of the breast cancer cell line 4T1 with adenoviral vectors encoding the HA117 gene and the green fluorescence protein gene (GFP) (Ad-GFP-HA117), the MDR1 and GFP (Ad-GFP-MDR1) or GFP (Ad-GFP) was respectively carried out. The transduction efficiency and the multiplicity of infection (MOI) were detected by fluorescence microscope and flow cytometry. The transcription of HA117 gene and MDR1 gene were detected by reverse transcription polymerase chain reaction (RT-PCR). Western blotting analysis was used to detect the expression of P-glycoprotein (P-gp) but the expression of HA117 could not be analyzed as it is a novel gene and its antibody has not yet been synthesized. The drug-excretion activity of HA117 and MDR1 were determined by daunorubicin (DNR) efflux assay. The drug sensitivities of 4T1/HA117 and 4T1/MDR1 to chemotherapeutic agents were detected by Methyl-Thiazolyl-Tetrazolium (MTT) assay., Results: The transducted efficiency of Ad-GFP-HA117 and Ad-GFP-MDR1 were 75%-80% when MOI was equal to 50. The transduction of Ad-GFP-HA117 and Ad-GFP-MDR1 could increase the expression of HA117 and MDR1. The drug resistance index to Adriamycin (ADM), vincristine (VCR), paclitaxel (Taxol) and bleomycin (BLM) increased to19.8050, 9.0663, 9.7245, 3.5650 respectively for 4T1/HA117 and 24.2236, 11.0480, 11.3741, 0.9630 respectively for 4T1/MDR1 as compared to the control cells. There were no significant differences in drug sensitivity between 4T1/HA117 and 4T1/MDR1 for the P-gp substrates (ADM, VCR and Taxol) (P < 0.05), while the difference between them for P-gp non-substrate (BLM) was statistically significant (P < 0.05). DNR efflux assay confirmed that the multidrug resistance mechanism of HA117 might not be similar to that of MDR1., Conclusions: These results confirm that HA117 is a strong MDR gene in both HL-60 and 4T1 cells. Furthermore, our results indicate that the MDR mechanism of the HA117 gene may not be similar to that of MDR1.

Ligaments and tendons are dense connective tissues that are important in transmitting forces and facilitate joint articulation in the musculoskeletal system. Their injury frequency is high especially for those that are functional important, like the anterior cruciate ligament (ACL) and medial collateral ligament (MCL) of the knee as well as the glenohumeral ligaments and the rotator cuff tendons of the shoulder. Because the healing responses are different in these ligaments and tendons after injury, the consequences and treatments are tissue- and site-specific. In this review, we will elaborate on the injuries of the knee ligaments as well as using functional tissue engineering (FTE) approaches to improve their healing. Specifically, the ACL of knee has limited capability to heal, and results of non-surgical management of its midsubstance rupture have been poor. Consequently, surgical reconstruction of the ACL is regularly performed to gain knee stability. However, the long-term results are not satisfactory besides the numerous complications accompanied with the surgeries. With the rapid development of FTE, there is a renewed interest in revisiting ACL healing. Approaches such as using growth factors, stem cells and scaffolds have been widely investigated. In this article, the biology of normal and healing ligaments is first reviewed, followed by a discussion on the issues related to the treatment of ACL injuries. Afterwards, current promising FTE methods are presented for the treatment of ligament injuries, including the use of growth factors, gene delivery, and cell therapy with a particular emphasis on the use of ECM bioscaffolds. The challenging areas are listed in the future direction that suggests where collection of energy could be placed in order to restore the injured ligaments and tendons structurally and functionally.