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Cancer cells prefer to utilizing aerobic glycolysis to generate energy and anabolic metabolic intermediates for cell growth. However, whether the activities of glycolytic enzymes can be regulated by specific posttranslational modifications, such as SUMOylation, in response to oncogenic signallings, thereby promoting the Warburg effect, remain largely unclear. Here, we demonstrate that phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3), a key glycolytic enzyme, interacts with SUMO-conjugating enzyme UBC9 and is SUMOylated at K302 in glioblastoma cells. Expression of UBC9, which competitively prevents the binding of ubiquitin E3 ligase APC/C to PFKFB3 and subsequent PFKFB3 polyubiquitination, increases PFKFB3 stability and expression. Importantly, EGFR activation increases the interaction between UBC9 and PFKFB3, leading to increased SUMOylation and expression of PFKFB3. This increase is blocked by inhibition of EGFR-induced AKT activation whereas expression of activate AKT by itself was sufficient to recapitulate EGF-induced effect. Knockout of PFKFB3 expression decreases EGF-enhanced lactate production and GBM cell proliferation and this decrease was fully rescued by reconstituted expression of WT PFKFB3 whereas PFKFB3 K302R mutant expression abrogates EGF- and UBC9-regulated lactate production and GBM cell proliferation. These findings reveal a previously unknown mechanism underlying the regulation of the Warburg effect through the EGFR activation-induced and UBC9-mediated SUMOylation and stabilization of PFKFB3. [ABSTRACT FROM AUTHOR]

Oleanolic acid (OA) has been widely studied because of its pleiotropic therapeutic and preventive effect on various diseases. However, the mechanisms of OA's action are still not clear yet, especially its suppressing effect on transformed cells. In this work, we found that OA induced autophagy in normal tissue-derived cells without cytotoxicity. OA-induced autophagy was shown to decrease the proliferation of KRAS-transformed normal cells and to impair their invasion and anchorage-independent growth. Interrupting autophagy rescued OA’s effect on the transformed cells. Mouse model experiments also demonstrated that OA suppressed the growth of KRAS-transformed breast epithelial cell MCF10A-derived tumor xenograft by inducing autophagy. Finally, we identified that OA induced autophagy in normal cells by inhibiting the activation of Akt/mTOR/S6K signaling. In conclusions, we found that OA treatment permitted normal cells to undergo autophagy. The induced autophagy was required for OA to prevent or delay the growth of transformed normal cells. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) lacks effective treatment, and the patients rapidly develop the acquired resistance to sorafenib with less defined mechanisms. Here, we demonstrate that transcriptional factor myocyte enhancer factor 2D (MEF2D) overexpression is detected in sorafenib-resistant HCC specimens and HCC cell lines and predicts poor prognosis of sorafenib-treated HCC patients. Mechanistically, MEF2D in complex with histone deacetylase HDAC4 directly binds to the SPRY4 promoter regions and suppresses the transcriptional expression of SPRY4, which is a negative regulator of MAPK/ERK signaling pathway. Inhibition of HDAC4 with its clinically used inhibitor induces SPRY4 expression and inhibition of ERK activity, resulting in sensitization of HCC cells to sorafenib-induced apoptosis and greatly improved inhibition of liver tumor growth in mice with sorafenib treatment. These findings highlight the critical role of coupling HDAC4 with MEF2D in activation of ERK by suppressing SPRY4 and underscore the great potential to improve HCC treatment by combined administration of sorafenib with HDAC4 inhibitors. [ABSTRACT FROM AUTHOR]

Abstract: Hepatocellular carcinoma (HCC) is a hypervascular cancer characterized by rapid progression as well as resistance to conventional chemotherapy. It has been shown that microRNAs play critical roles in pathogenesis of HCC. MicroRNA-122 (miR-122) is a liver-specific microRNA and is frequently downregulated in HCC. In the present study, we investigated whether restoration of miR-122 in HCC cells could render cells sensitive to chemotherapeutic agents adriamycin (ADM) or vincristine (VCR). Our data showed that overexpression of miR-122 in HCC cells induced by adenovirus expressing miR-122 could render cell sensitive to ADM or VCR. Analysis of cell cycle distribution showed that the anti-proliferative effect of miR-122 is associated with increase of cell number in the G2/M phase. Moreover, treatment with Ad-miR122 and ADM or VCR resulted in high accumulation of HCC cells in G2/M phase. We further demonstrated that overexpression of miR-122 could modulate the sensitivity of the HCC cells to chemotherapeutic drugs through downregulating MDR related genes MDR-1, GST-π, and MRP, antiapoptotic gene Bcl-w and cell cycle related gene cyclin B1. Taken together, our findings demonstrated that combination of Ad-miR122 with chemotherapeutic agents inhibited HCC cell growth by inducing G2/M arrest and that this arrest is associated, at least in part, with reduced expression of MDR related genes and Cyclin B1. [Copyright &y& Elsevier]

Abstract Chimeric antigen receptor T (CAR-T) cell therapy provides possibility for the treatment of malignancies since clinical trials have shown that CAR-T therapy has a significant anti-tumor effect. Although many efforts have been made to improve the efficacy and reduce the side effects of CAR-T therapy, there are still many problems to solve. With the rapid development of this field, combination immunotherapy has been proved to improve the efficacy of CAR-T therapy. Studies have shown that radiotherapy, chemotherapy, oncolytic virotherapy, BTK inhibitors and immune checkpoint blockade-based therapy may further enhance the efficacy of CAR-T therapy while CRISPR/Cas9 technology and IL-1 blockade may improve the safety. In this review, we summarized the advantages and the mechanisms of the combination immunotherapy based on CAR-T cell therapy. [ABSTRACT FROM AUTHOR]

Gliomas is the most common type of intracranial primary malignant tumor and it accounts for ∼80% of primary malignant tumors of the central nervous system. At present, surgical resection with adjuvant radiotherapy and temozolomide adjuvant chemotherapy combined with radiotherapy are the only standard treatments for glioma. However, but overall survival of patients is only 15 months. Glioma is resistant to radiotherapy and chemotherapy, and this malignant behavior leads to a high recurrence rate. Therefore, the use of therapeutics is usually ineffective. As a result, patients with glioma do not significantly benefit from standard treatment. There is therefore an urgent need to develop novel diagnostic approaches and, in particular, more effective treatment strategies. The application of gene expression microarrays provides a feasible and effective way to study gliomas. The present study therefore aimed to identify the key protein-coding genes of glioma using bioinformatics methods and thereby search, for novel biomarkers and therapeutic targets for the treatment of glioma. First, mRNA microarray datasets were selected and obtained from the Gene Expression Omnibus database to identify differentially expressed genes (DEGs) between gliomas and normal tissues. The DEGs were clarified using Gene Ontology (GO), the Kyoto Encyclopedia of Genes and Genomes (KEGG), Protein-Protein Interaction (PPI) network and statistical analysis. Subsequently, reverse transcription-quantitative PCR (RT-qPCR)and western blot were used to verify the results of the bioinformatics analysis. A total of 400 DEGs were identified in glioma and they were enriched in several cancer-related GO and KEGG pathways. In the PPI network, it was observed that G-protein signal regulatory protein 4 (RGS4), thymidine phosphorylase, collagen type VI alpha-1, Src homology 2 domain-containing transforming protein1(SHC1) and ring finger protein 135 exhibited a strong protein-protein interaction. Furthermore,. Subsequently, brain damaged tissues and glioma cell lines were selected for RT-qPCR and western blotting analysis. The results demonstrated that RGS4 was highly expressed in glioma cell lines. In conclusion, RGS4 may be a key protein-coding gene in glioma. RGS4 should therefore be studied further to verify its feasibility and effectiveness as a potential glioma biomarker and therapeutic target. [ABSTRACT FROM AUTHOR]

Background The invasion and recurrence of clinical nonfunctioning pituitary adenomas (NFA) often lead to surgical treatment failure. Circular RNAs (circRNAs) are a novel class of RNAs whose 3′ and 5′ ends are joined together and have been shown to play important roles in cancer development. Until now, the roles of circRNAs have remained unclear in invasive and recurrent NFA. Methods We detected and summarized the circRNA expression pattern in 75 NFA tissues from 10 noninvasive cases and 65 invasive cases and 9 pairs of NFA tumor tissues from 9 recurrent cases by circRNA microarrays. Accordingly, functional enrichment analysis and pathway analysis were performed and the circRNA-microRNA (miRNA) network was generated by bioinformatic analysis tools. Five new invasive NFA samples and 5 noninvasive NFA samples were collected to measure the microarray results. Results A total of 570 dysregulated circRNAs (invasive tumor vs. noninvasive tumor) and 10 upregulated circRNAs (recurrent tumor tissue vs. first surgery tumor tissue) were identified based on the situation (fold change >2; P < 0.05). The parental genes of the dysregulated circRNAs in the comparison between invasion tumor and noninvasion tumor were found to be enriched in some cell adhesion signaling pathways such as Focal adhesion, Hippo signaling pathway, PI3K-Akt signaling pathway, and Adherens junction. The circRNA-miRNA network showed that the dysregulated circRNA may function as miRNA sponges. Conclusions This is the first study to conduct and comprehensively analyze the circRNA expression profile in invasive and recurrent NFA. Our finding will provide evidence for the significance of circRNAs in NFA diagnosis, prognosis, and clinical treatment. [ABSTRACT FROM AUTHOR]