Hsa_circ_0003159 inhibits gastric cancer progression by regulating miR-223-3p/NDRG1 axis.

BACKGROUND: Abnormally expressed circular RNAs (circRNAs) are implicated in the development and treatment of gastric cancer (GC). Previous study has reported that hsa_circ_0003159 is expressed in GC. However, the role and mechanism of hsa_circ_0003159 in GC progression remain unclear. METHODS: GC tissues and normal tissues were harvested from 55 patients in this study. The levels of hsa_circ_0003159, microRNA (miR)-223-3p and N-myc downstream regulated gene 1 (NDRG1) were measured by quantitative real-time polymerase chain reaction or western blot. Cell proliferation, migration, invasion and apoptosis were determined by cell counting kit (CCK)-8, transwell assay, flow cytometry and western blot, respectively. The target association of miR-223-3p-hsa_circ_0003159 and miR-223-3p-NDRG1 was explored by dual-luciferase reporter assay. Xenograft model was established to assess the roles of hsa_circ_0003159 in GC in vivo. RESULTS: Hsa_circ_0003159 was lowly expressed in GC tissues and cells and mainly presented in the cytoplasm. Low expression of hsa_circ_0003159 was associated with lower overall survival and disease-free survival. Hsa_circ_0003159 overexpression inhibited proliferation, migration and invasion but induced apoptosis in GC cells. MiR-223-3p was a target of hsa_circ_0003159 and abated the effect of hsa_circ_0003159 on proliferation, migration, invasion and apoptosis in GC cells. Hsa_circ_0003159 promoted NDRG1 expression by competitively sponging miR-223-3p. Knockdown of NDRG1 reversed the suppressive effect of hsa_circ_0003159 on GC progression. Besides, hsa_circ_0003159 decreased GC cell xenograft tumor growth by regulating miR-223-3p and NDRG1. CONCLUSION: Hsa_circ_0003159 suppressed proliferation, migration, invasion and xenograft tumor growth but promoted apoptosis by decreasing miR-223-3p and increasing NDRG1 in GC, indicating a novel target for treatment of GC.

RETRACTED: Long non-coding RNA LINC00978 promotes cell proliferation and tumorigenesis via regulating microRNA-497/NTRK3 axis in gastric cancer.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editors-in-Chief. Given the comments of Dr Elisabeth Bik regarding this article "…the Western blot bands in all 400+ papers are all very regularly spaced and have a smooth appearance in the shape of a dumbbell or tadpole, without any of the usual smudges or stains. All bands are placed on similar looking backgrounds, suggesting they were copy/pasted from other sources, or computer generated", the journal requested the authors to provide the raw data. However, the authors were not able to fulfil this request and therefore the Editors-in-Chief decided to retract the article.

Exosome-Mediated Transfer of lncRNA HOTTIP Promotes Cisplatin Resistance in Gastric Cancer Cells by Regulating HMGA1/miR-218 Axis.

BACKGROUND: Chemoresistance has become a major obstacle for cancer therapy in clinic. Long noncoding RNAs (lncRNAs) have been reported to play critical roles in the development of chemoresistance in various tumors, including gastric cancer (GC). However, the role of HOXA transcript at the distal tip (HOTTIP) within extracellular vesicles (exosomes) in cisplatin-resistant GC cells remains largely unknown. MATERIALS AND METHODS: Cell proliferation, migration and invasion were detected using Cell Counting Kit-8 (CCK-8) and transwell assays, respectively. Western blot assay was employed to analyze the protein levels of E-cadherin, N-cadherin, Vimentin, CD63, CD83, GRP78, HMGA1, and high-mobility group A1 (HMGA1). The expression levels of HOTTIP, microRNA-218 (miR-218) and HMGA1were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The interaction between miR-218 and HOTTIP or HMGA1 was predicted by bioinformatics software and confirmed by the dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. RESULTS: Cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) were promoted in cisplatin-resistant GC cells. HOTTIP level was upregulated in cisplatin-resistant GC cells and its downregulation enhanced cisplatin sensitivity. Moreover, extracellular HOTTIP could be incorporated into exosomes and transmitted to sensitive cells, thus disseminating cisplatin resistance. Additionally, exosomal HOTTIP promoted cisplatin resistance via activating HMGA1 in GC cells. Interestingly, HMGA1 was a target of miR-218 and miR-218 could directly bind to HOTTIP. Clinically, high expression of exosomal HOTTIP in serum was associated with poor response to cisplatin treatment in GC patients. CONCLUSION: Exosomal HOTTIP contributed to cisplatin resistance in GC cells by regulating miR-218/HMGA1 axis, providing a novel avenue for the treatment of GC.

High Expressions of CUL4A and TP53 in Colorectal Cancer Predict Poor Survival.

BACKGROUND/AIMS: Cullin 4A (CUL4A) is vital in cell survival, development, growth and cell cycle, it plays an important role in chaperone-mediated ubiquitination and interacts with TP53 in carcinogenesis. However, the clinicopathologic significance of CUL4A expression in colorectal cancer is unknown; in particular, the prognostic value of CUL4A combined with TP53 expression has not been explored. METHODS: We analyzed the expression of CUL4A in both public database (Oncomine) and 180 cases of colorectal cancer and paired normal tissues by real-time polymerase chain reaction and western blotting. Colony formation, wound healing, migration and invasion assays and tumorigenesis in nude mice were used to explore the function of CUL4A in CRC proliferation and metastasis in vitro and in vivo. Markers of epithelial to mesenchymal transition (EMT) were evaluated by western blotting. Immunohistochemistry (IHC) was used to analyse the relationship between CUL4A expression and E-cadherin expression. RESULTS: CUL4A and TP53 protein expression was significantly higher in cancerous tissues compared to normal tissues. Significant correlation between CUL4A and TP53 expression was observed. CUL4A expression was an independent prognostic factor for overall survival (OS) and disease-free survival (DFS). Interestingly, patients with tumors that had both CUL4A overexpression and mutant TP53 protein accumulation relapsed and died within a significantly short period after surgery (P < 0.001). Multivariate analysis showed that patients with both CUL4A+ and TP53+ positive tumors had extremely poor OS and DFS. Knockdown of CUL4A by a short interfering RNA (siRNA) significantly suppressed the progression of EMT, proliferation, migration, and invasion of colon cancer cells in vitro and tumor growth in vivo. ZEB1 silencing blocked CUL4A-driven these processes. CONCLUSION: CUL4A expression correlated positively with the prognosis of colorectal cancer. Mechanistically, ZEB1 was confirmed to mediate the function of CUL4A in regulating the EMT. The assessment of both CUL4A and mutant TP53 expression will be helpful in predicting colon cancer prognosis.

MiR-103 alleviates autophagy and apoptosis by regulating SOX2 in LPS-injured PC12 cells and SCI rats.

OBJECTIVES: Recent studies revealed that microRNAs (miRNAs) may play crucial roles in the responses and pathologic processes of spinal cord injury (SCI). This study aimed to investigate the effect and the molecular basis of miR-103 on LPS-induced injuries in PC12 cells in vitro and SCI rats in vivo. MATERIALS AND METHODS: PC12 cells were exposed to LPS to induce cell injuries to mimic the in vitro model of SCI. The expression of miR-103 and SOX2 in PC12 cells were altered by transient transfections. Cell viability and apoptotic cell rate were measured by CCK-8 assay and flow cytometry assay. Furthermore, Western blot analysis was performed to detect the expression levels of apoptosis- and autophagy- related proteins, MAPK/ERK pathway- and JAK/STAT pathway-related proteins. In addition, we also assessed the effect of miR-103 agomir on SCI rats. RESULTS: LPS exposure induced cell injuries in PC12 cells. miR-103 overexpression significantly increased cell viability, reduced cell apoptosis and autophagy, and opposite results were observed in miR-103 inhibition. miR-103 attenuated LPS-induced injuries by indirect upregulation of SOX2. SOX2 overexpression protected PC12 cells against LPS-induced injuries, while SOX2 inhibition expedited LPS-induced cell injuries. Furthermore, miR-103 overexpression inhibited MAPK/ERK pathway and JAK/STAT pathway through upregulation of SOX2. We also found that miR-103 agomir inhibited cell apoptosis and autophagy in SCI rats. CONCLUSION: This study demonstrates that miR-103 may represent a protective effect against cell apoptosis and autophagy in LPS-injured PC12 cells and SCI rats by upregulation of SOX2 expression.

Erratum: Meprin α combined with CEA and CA19-9 improves prognostic prediction for surgically treated colorectal cancer patients.

[This corrects the article on p. 10441 in vol. 10, PMID: 31966381.].

The prognostic significance of FBXO2 expression in colorectal cancer.

Colorectal cancer is the third most frequently diagnosed malignancy, and the prognosis at advanced tumor stages remains poor. FBXO2, a member of the F-box protein family, is a cytoplasmic protein and an ubiquitin ligase. The aim of this study was to investigate the role of FBXO2 in colorectal cancer. The expression levels of Ki67, N-cadherin and FBXO2 were detected in 195 pairs of primary CRC tissues using immunohistochemistry (IHC). The associations among Ki67, N-cadherin, and FBXO2 expression, as well as the clinicopathological parameters, were analyzed. Survival curves were calculated with the Kaplan-Meier method. Univariate and multivariate analyses were performed to explore the prognostic significance of Ki67, N-cadherin, and FBXO2 expression. We found that the positive rates of Ki67, N-cadherin and FBXO2 expression in CRC tissue samples were 55.9%, 65.1%, 62.6%, respectively. The high expression levels of Ki67 and N-cadherin were significantly correlated with CRC size (P = 0.01) and metastasis (P = 0.01), respectively. The high expression level of FBXO2 was significantly correlated with CRC metastasis (P = 0.04) and AJCC stage (P = 0.029). A Cox regression analysis revealed that FBXO2 is an independent prognostic factor for CRC patients (HR 1.817, 95% CI 1.106-2.983, P = 0.018). FBXO2 may serve as a biomarker for metastasis and a reliable predictor for poor prognosis in CRC patients.

miR-133b suppresses metastasis by targeting HOXA9 in human colorectal cancer.

Functions and mechanisms of microRNA (miRNA) involved in colorectal cancer (CRC) metastasis are largely unknown. Here, a miRNA microarray analysis was performed in CRC primary tissues and metastatic hepatic tissues to disclose crucial miRNA involved in CRC metastasis. MiR-133b was decreased and negatively correlated with metastasis in CRC. Overexpression of miR-133b significantly suppressed metastasis of CRC in vitro and in vivo. HOXA9 was identified as a direct and functional target of miR-133b. In addition, HOXA9 was negatively correlated with miR-133b and promoted CRC malignant progress. Moreover, miR-133b decreased HOXA9 expression, and subsequently downregulated ZEB1 and upregulated E-cadherin expression. Intriguingly, lower miR-133b and higher HOXA9 expression significantly contributed to poorer outcomes in CRC patients. Multivariate analysis indicated that miR-133b was an independent and significant predictor of CRC patient overall survival. In conclusion, we newly determined that miR-133b targeted the HOXA9/ZEB1 pathway to promote tumor metastasis in CRC cells. This axis provided insights into the mechanism underlying miRNA regulation of CRC metastasis and a novel therapeutic target for CRC treatment.

Isoflurane anesthesia induces liver injury by regulating the expression of insulin-like growth factor 1.

It has been suggested that isoflurane may cause perioperative liver injury. However, the mechanism of its action remains unknown. The purpose of the present study was to determine this possible mechanism. Sprague-Dawley rats were randomly assigned into one of three groups (all n=12): Control group (exposed to mock anesthesia), isoflurane group (exposed to 2% isoflurane for 90 min), and isoflurane + insulin-like growth factor 1 (IGF-1) group (exposed to 2% isoflurane for 90 min and then treated with IGF-1). Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting were conducted to determine the levels of expression of IGF-1 and its receptor IGF-R. Liver necrosis was assessed by histological examination. TUNEL assay was performed to determine the apoptosis of hepatic cells. In addition, the levels of the proteins caspase-3 and B-cell lymphoma-extra large (Bcl-xL) were measured. Compared with the control group, levels of IGF-1 and IGF-1R mRNA and protein were significantly decreased following exposure to isoflurane (all P<0.05). The necrosis rate and liver apoptosis were significantly increased in the group treated with isoflurane alone compared with the control group (P<0.05), but were significantly decreased compared with the isoflurane group following application of IGF-1 (P<0.05). Additionally, isoflurane exposure significantly increased levels of caspase-3 compared with the control group (P<0.05), but decreased levels of Bcl-xL (P<0.05). By contrast, application of IGF-1 reversed these changes. The present study therefore suggests that isoflurane induces liver injury in part by regulating the expression of IGF-1 and that application of IGF-1 may protect against liver injury induced by isoflurane exposure.

Meprin α combined with CEA and CA19-9 improves prognostic prediction for surgically treated colorectal cancer patients.

BACKGROUND: Carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) are generally used as tumour markers in patients with colorectal cancer (CRC), and meprin α might be an additional marker. METHODS: The preoperative expression of serum CEA and CA19-9 was evaluated using a C12 protein biochip system, and tissue meprin α expression in CRC cells was detected by immunohistochemistry. The relationships of these indexes with clinicopathological parameters and the survival of CRC patients were analysed. RESULTS: Of the 147 CRC patients, the preoperative seropositive rates for CEA and CA19-9 were 51.70% and 44.22%, respectively, and the tissue meprin α positive rate was 39.46%. Preoperative seropositivity for CEA was correlated with tumour size (P = 0.019), T stage (P = 0.005) and staging of CRC based on the American Joint Committee on Cancer (AJCC) guidelines (P = 0.032). The preoperative seropositive rate for CA19-9 was correlated with AJCC tumour stage (P = 0.031). High expression of meprin α was significantly correlated with distant CRC metastasis (P = 0.003), serum CEA (P = 0.002) and serum CA19-9 (P = 0.001). The combination of the three markers was an independent prognostic factor in patients with CRC (HR 3.985, 95% CI 1.106-14.361, P = 0.035 for overall survival). CONCLUSIONS: Tissue meprin α expression may be a useful predictor of metastasis and prognosis in CRC. The combined detection of the three markers may also be helpful to improve the accuracy of CRC prognosis monitoring.

The autophagy inhibitor 3-methyladenine restores sevoflurane anesthesiainduced cognitive dysfunction and neurons apoptosis.

This study was designed to explore the effect of 3-methyladenine (3-MA) on sevoflurane anesthesia-induced cognitive dysfunction. A total of 60 C57BL/6 (5-8 months old) mice were randomly arranged into 3 groups: Control, sevoflurane (Sev) and Sev+3-MA group with 3-MA administration was performed during Sev administration. Morris water maze and Y-maze test were performed to examine the behavioral disorders. Moreover, hippocampal neuronal cell apoptosis and expression of autophagy related genes were detected. Sevoflurane induced cognitive dysfunction in mice showing significant longer escape latency, lower number of correct response, higher apoptotic neurons, and higher expression of autophagy related genes. However, additional 3-MA administration inhibited the effect of sevoflurane on cognitive dysfunction by shorting escape latency, reducing correct response number, inhibiting neurons apoptosis and autophagy genes expression. 3-MA additional administration inhibited sevoflurane anesthesia-induced cognitive dysfunction on mice. 3-MA might be usefull as an inhibitor for sevoflurane anesthesia-induced cognitive dysfunction in clinical trials.

Evaluation of Neuroprotective Effect of Thymoquinone Nanoformulation in the Rodent Cerebral Ischemia-Reperfusion Model.

The purpose of the present study was to evaluate the neuroprotective efficacy of optimized thymoquinone loaded PLGA-chitosan nanoparticles delivered via nose to brain route in the rodent cerebral ischemia-reperfusion model. The neuroprotective efficacy of the optimized thymoquinone loaded PLGA-chitosan nanoparticles was evaluated in middle cerebral artery occluded rats by various pharmacodynamic and biochemical studies. The pharmacokinetics of thymoquinone loaded PLGA-chitosan nanoparticles in the brain and blood plasma together with qualitative localization of florescent labelled PLGA-chitosan nanoparticles in brain tissues were also determined. Intranasal delivery of optimized thymoquinone loaded PLGA-chitosan nanoparticles (183.5 ± 8.2 nm, 33.63 ± 2.25 mV) to brain significantly reduced the ischemia infarct volume and enhanced the locomotor activity and grip strength in the middle cerebral artery occluded rats. Biochemical studies showed that intranasal delivery of thymoquinone loaded PLGA-chitosan nanoparticles significantly reduced the lipid peroxidation but elevated the glutathione, catalase, and superoxide dismutase in the brain of middle cerebral artery occluded rats. The pharmacokinetic and localization studies showed that thymoquinone loaded PLGA-chitosan nanoparticles facilitated the delivery of thymoquinone to brain by intranasal nose to brain transport pathways and enhanced their pharmacokinetic profile in brain tissues. Thus, intranasal delivery of thymoquinone loaded PLGA-chitosan nanoparticles to brain could be potentially used for the neuroprotection and treatment of cerebral ischemia.

Curcumin improves bone microarchitecture in glucocorticoid-induced secondary osteoporosis mice through the activation of microRNA-365 via regulating MMP-9.

The present study aimed to investigate bone microarchitecture of the proximal tibia in glucocorticoid-induced osteoporosis (GIOP) mice, and the underlying molecular mechanisms of curcumin in DXM-induced osteoporosis were performed. DXM-treated facilitated to induce hypercalciuria in mice, and curcumin-treated showed a decrease in urine calcium. Curcumin reversed DXM-induced bone resorption, including an increase in serum OCN and a decrease in bone resorption markers CTX and TRAP-5b. H&E staining showed the increased disconnections and separation in trabecular bone network as well as the reduction of trabecular thickness throughout the proximal metaphysis of tibia in GIOP group. Importantly, curcumin reversed DXM-induced trabecular deleterious effects and stimulated bone remodeling. The further evidence showed that curcumin supplement significantly decreased the TRAP-positive stained area and inhibited the activity of OPG/RANKL/RANK signaling in the GIOP mice. Moreover, bioinformatics analysis suggested that miR-365 was a regulator of MMP9. The levels of miR-365 were markedly suppressed; however, curcumin treatment could reverse the downregulation of miR-365 in the tibia of GIOP mice. Simultaneously, the results demonstrated that the mRNA and protein expression of MMP-9 were significantly increased in GIOP mice compared with that of the control group. Curcumin treatment could suppress the expression of MMP-9 in the tibia of GIOP mice. The present study demonstrated the protective effects of curcumin against bone deteriorations in the experimentally DIOP mice, and the underlying mechanism was mediated, at least partially, through the activation of microRNA-365 via suppressing MMP9.