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Combination of metformin with ABT-263 had no significant growth inhibition effect on HEK-293 cells.

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ATG4B, a cysteine protease promoting autophagosome formation by reversibly modifying Atg8-family proteins, plays a vital role in controlling macroautophagy/autophagy initiation in response to stress. However, the molecular mechanism underlying the regulation of ATG4B activity is far from well elucidated. In the current study, we firstly revealed that the acetylation level of ATG4B at lysine residue 39 (K39) is strongly involved in regulating its activity and autophagy. Specifically, SIRT2 deacetylates ATG4B K39, enhancing ATG4B activity and autophagic flux, which can be antagonized by EP300/p300. Starvation treatment contributes to EP300 suppression and SIRT2 activation, promoting the deacetylation of ATG4B K39, which leads to the elevation of ATG4B activity and finally autophagy initiation. Mechanistic investigation showed that starvation reduces CCNE (cyclin E), resulting in the downregulation of the CCNE-CDK2 protein complex, decreasing the phosphorylation of SIRT2 Ser331 and finally activating SIRT2. In addition, we confirmed that SIRT2 promotes autophagy via suppressing acetylation of ATG4B at K39 using

Eukaryotes initiate autophagy when facing environmental changes such as a lack of external nutrients. However, the mechanisms of autophagy initiation are still not fully elucidated. Here, we showed that deacetylation of ATG4B plays a key role in starvation-induced autophagy initiation. Specifically, we demonstrated that ATG4B is activated during starvation through deacetylation at K39 by the deacetylase SIRT2. Moreover, starvation triggers SIRT2 dephosphorylation and activation in a cyclin E/CDK2 suppression–dependent manner. Meanwhile, starvation down-regulates p300, leading to a decrease in ATG4B acetylation at K39. K39 deacetylation also enhances the interaction of ATG4B with pro-LC3, which promotes LC3-II formation. Furthermore, an in vivo experiment using Sirt2 knockout mice also confirmed that SIRT2-mediated ATG4B deacetylation at K39 promotes starvation-induced autophagy initiation. In summary, this study reveals an acetylation-dependent regulatory mechanism that controls the role of ATG4B in autophagy initiation in response to nutritional deficiency.

To investigate the radioactive iodine-125 (I-125) seed on migrating and invading of hepatocellular carcinoma (HCC) cells and its mechanism, the irradiation of PLC and Huh7 cells was carried out with I-125 seeds in vitro. Cell counting kit 8 assay was employed to measure cell viability. Cell migration was evaluated by using wound-healing assay. Cell invasion was detected by Transwell assay; RT-PCR and Western blot were used for the detection of the mRNA and proteins of TGF

Background Aberrant expression of circular RNAs contributes to the initiation and progression of cancers, but the underlying mechanism remains elusive. Methods RNA-seq and qRT-PCR were performed to screen differential expressed circRNAs between gastric cancer tissues and adjacent normal tissues. Candidate circRNA (circMRPS35) was screened out and validated by qRT-PCR. Cell proliferation and invasion ability were determined by CCK-8 and cell invasion assays. RNA-seq, GO-pathway, RNA pull-down and ChIRP were further applied to search for detailed mechanism. Results Here, a novel circRNA named circMRPS35, was screened out by RNA-seq in gastric cancer tissues, whose expression is related to clinicopathological characteristics and prognosis in gastric cancer patients. Biologically, circMRPS35 suppresses the proliferation and invasion of gastric cancer cells in vitro and in vivo. Mechanistically, circMRPS35 acts as a modular scaffold to recruit histone acetyltransferase KAT7 to the promoters of FOXO1 and FOXO3a genes, which elicits acetylation of H4K5 in their promoters. Particularly, circMRPS35 specifically binds to FOXO1/3a promoter regions directly. Thus, it dramatically activates the transcription of FOXO1/3a and triggers subsequent response of their downstream target genes expression, including p21, p27, Twist1 and E-cadherin, resulting in the inhibition of cell proliferation and invasion. Moreover, circMRPS35 expression positively correlates with that of FOXO1/3a in gastric cancer tissues. Conclusions Our findings not only reveal the pivotal roles of circMRPS35 in governing histone modification in anticancer treatment, but also advocate for triggering circMRPS35/KAT7/FOXO1/3a pathway to combat gastric cancer.

Epirubicin (EPI)-based transarterial chemoembolization is an effective therapy for advanced hepatocellular carcinoma (HCC). However, EPI-induced survivin expression limits its tumor-killing potential in HCC. Interestingly, (-)-gossypol ((-)-Gsp), a male contraceptive, suppresses various malignancies. More importantly, (-)-Gsp also holds promise for enhancing the antitumor effects of chemotherapy in numerous cancer types. In the present study, we demonstrated for the first time that (-)-Gsp-sensitized EPI inhibited cell growth and induced apoptosis of HCC cells in vitro. Furthermore, (-)-Gsp sensitized EPI by attenuating the EPI-elevated survivin protein levels. Mechanistic studies showed that EPI stimulated survivin protein synthesis by promoting translation initiation, which was alleviated by (-)-Gsp mainly through suppressing the AKT-4EBP1/p70S6K-survivin and ERK-4EBP1-survivin pathways. HCC xenograft experiments in nude mice also showed that (-)-Gsp treatment acted synergistically with EPI to repress xenograft tumor growth. Overall, our proof-of-concept results may pave the way for novel strategies for the treatment of HCC based on the combination of EPI and (-)-Gsp.

Colorectal cancer liver metastasis (CRLM) is the leading cause of colorectal cancer-related deaths and remains a clinical challenge. Enhancement of glucose uptake is involved in CRLM; however, whether long noncoding RNAs (lncRNAs) participate in these molecular events remains largely unclear. Here, we report an lncRNA, GAL (glucose transporter 1 (GLUT1) associated lncRNA), that was upregulated in CRLM tissues compared with primary colorectal cancer (CRC) tissues or matched normal tissues and was associated with the overall survival rates of CRLM patients. Functionally, GAL served as an oncogene because it promoted CRC cell migration and invasion in vitro and enhanced the ability of CRC cells to metastasize from the intestine to the liver in vivo. Mechanistically, GAL interacted with the GLUT1 protein to increase GLUT1 SUMOylation, inhibiting the effect of the ubiquitin-proteasome system on the GLUT1 protein. GLUT1-knockout (-/+) repressed the GAL-mediated increase in CRC cell uptake of glucose, migrate, and invade in vitro, as well as metastasis from the intestine to the liver in vivo, and enforced expression of GLUT1 rescued GAL knockout-induced biological functions in CRC cells. Taken together, our findings demonstrated that GAL promotes CRLM by stabilizing GLUT1, suggesting that the GAL-GLUT1 complex may act as a potential therapeutic target for CRLM.

Colorectal cancer (CRC) usually gives rise to transcoelomic spread and ultimately causes peritoneal carcinomatosis (PC). However, mechanism studies, especially the immunological basis of colorectal PC, are rarely revealed due to lack of a suitable PC model. Here we selected a mouse colorectal cancer cell line MC-38 for intraperitoneal inoculation in the C57BL/6 mice to mimic the development of colorectal PC. We demonstrated that the injected CRC cells preferentially and rapidly migrated and colonized in the visceral fat tissues, but not in other visceral organs. With flow cytometric analysis, we found the proportions of spleen T cells and B cells were not affected by PC progression, while the ratios of blood CD4+ and CD8+ T cells were largely influenced. Especially, the quantity or activity of CD4+ and CD8+ T cells in visceral fats were intimately regulated by PC development. Taken together, we successfully constructed a colorectal PC model in immune-competent mice and revealed the alteration of adaptive immunity in PC development. Our study might potentiate the research and therapy strategies of colorectal PC.

Background: Long noncoding RNAs (lncRNAs) have been demonstrated to play essential roles in renal cell carcinoma (RCC). However, the role of lncRNA KCNQ1DN in RCC remains unclear. Methods: The expression of KCNQ1DN in RCC and the corresponding adjacent tissues was measured by qPCR. RNA fluorescence in situ hybridization (FISH) assay, methylation analysis, reporter gene assays and functional tests were performed to reveal the effects of KCNQ1DN on RCC. Results: In the present study, we found that lncRNA KCNQ1DN was notably decreased in RCC tissues and cell lines. RNA FISH assay showed that KCNQ1DN mainly localized to the cytoplasm. Methylation analysis revealed that the proximal region of KCNQ1DN promoter was hypermethylated in RCC tissues relative to the adjacent normal ones. Functional studies clarified that KCNQ1DN repressed the RCC cell growth and cell cycle progression. Mechanistically, KCNQ1DN inhibited the expression of c-Myc, which might further upregulate cyclin D1 and suppress p27 at mRNA and protein levels in RCC cells. Reporter gene assays revealed that the transcriptional activity of c-Myc promoter was inhibited by KCNQ1DN. The in vivo experiments in nude mice showed that KCNQ1DN overexpression dramatically repressed the growth of xenograft tumors and the expression of corresponding c-Myc. Conclusion: These results indicated that KCNQ1DN inhibit the growth of RCC cells in vitro and in vivo through repressing the oncogene c-myc, suggesting that KCNQ1DN may serve as a novel target for the treatment of RCC.

Background: Autophagy has been confirmed to be closely related to the growth and drug resistance of cancer cells, and autophagy related 4B (ATG4B) performs a crucial role in the process of autophagy. lncRNA CRNDE (colorectal neoplasia differentially expressed) promotes the growth of hepatocellular carcinoma (HCC) cells, but it is unclear whether the tumor-promoting effect of CRNDE is associated with the regulation of ATG4B and autophagy. Methods: The expression of CRNDE and ATG4B in HCC tissues and cells was detected by quantitative real-time PCR (qPCR) and Western blot. The effect of CRNDE on autophagy of HCC cells was examined by fluorescent assay, GFP-LC3 analysis and Western blot. The relationship among CRNDE, miR-543 and ATG4B was clarified using bioinformatic analysis, qPCR, Western blot and dual-luciferase reporter assay. The effect of CRNDE on sensitivity of sorafenib in HCC cells was evaluated in vitro and in vivo by CCK-8 assay, Western blot, Hoechst staining, flow cytometry, IHC staining and TUNEL assay. Results: CRNDE induced autophagy via upregulating ATG4B in HCC cells. Mechanistically, CRNDE enhanced the stability of ATG4B mRNA by suppressing miR-543, leading to the increase of ATG4B expression and autophagy in HCC cells. Moreover, sorafenib dramatically elevated CRNDE and ATG4B as well as autophagy. Knockdown of CRNDE significantly sensitized HCC cells to sorafenib in vitro and in vivo . Conclusion: The study has revealed the presence of “CRNDE/ATG4B/autophagy” pathway which alleviates the sensitivity of sorafenib in HCC cells, suggesting that this pathway may serve as a novel target to improve the killing effect of sorafenib in HCC treatment.

Liver cancer is one of the most common and high recurrence malignancies. Besides radiotherapy and surgery, chemotherapy also plays an essential role in the treatment of liver cancer. Sorafenib and sorafenib-based combination therapies have been proven efficacy against tumors. However, previous clinical studies have indicated that some patients with liver cancer are resistant to sorafenib treatment and the existing strategies are not satisfactory in the clinic. Therefore, it is urgent to investigate strategies to improve the effectiveness of sorafenib for liver cancer and to explore effective drug combinations. In the present study, we found that dichloroacetate (DCA) could significantly enhance the anti-tumor effect of sorafenib on liver cancer cells, including reduced viability and dramatically promoted apoptosis in liver cancer cells. Moreover, compared to sorafenib alone, the combination of DCA and sorafenib markedly increased the degradation of anti-apoptotic protein Mcl-1 by enhancing its phosphorylation. Overexpression of Mcl-1 could significantly attenuate the synergetic effect of DCA and sorafenib on apoptosis induction in liver cancer cells. Furthermore, we found that the ROS-JNK pathway was obviously activated in the DCA combined sorafenib group. The levels of ROS and p-JNK were dramatically up-regulated in the two drug combination groups. Antioxidant NAC could alleviate the synergetic effects of DCA and sorafenib on ROS generation, JNK activation, Mcl-1 degradation, and cell apoptosis. Moreover, DCA and sorafenib's effects on Mcl-1 degradation and apoptosis could also be inhibited by JNK inhibitor 'SP'600125. Finally, the synergetic effects of DCA and sorafenib on tumor growth suppression, Mcl-1 degradation and induction of apoptosis were also validated in liver cancer xenograft in vivo. These findings indicate that DCA enhances the anti-tumor effect of sorafenib via the ROS-JNK-Mcl-1 pathway in liver cancer cells. This study may provide new insights to improve the chemotherapeutic effect of sorafenib, which may be beneficial for further clinical application of sorafenib in liver cancer treatment.

MiR-124-3p has been identified as a novel tumor suppressor and a potential therapeutic target in hepatocellular carcinoma (HCC) through regulating its target genes. However, the upstream regulatory mechanisms of mir-124-3p in HCC has not been fully understood. The transcription factor liver X receptor (LXR) plays a critical role in suppressing the proliferation of HCC cells, but it is unclear whether LXR is involved in the regulation of mir-124-3p. In the present study, we demonstrated that the expression of mir-124-3p was positively correlated with that of LXR in HCC, and the cell growth of HCC was significantly inhibited by LXR agonists. Moreover, activation of LXR with the agonists up-regulated the expression of mir-124-3p, and in turn down-regulated cyclin D1 and cyclin-dependent kinase 6 (CDK6) expression, which are the target genes of mir-124-3p. Mechanistically, miR-124-3p mediates LXR induced inhibition of HCC cell growth and down-regulation of cyclin D1 and CDK6 expression. In vivo experiments also confirmed that LXR induced miR-124-3p expression inhibited the growth of HCC xenograft tumors, as well as cyclin D1 and CDK6 expression. Our findings revealed that miR-124-3p is a novel target gene of LXR, and regulation of the miR-124-3p-cyclin D1/CDK6 pathway by LXR plays a crucial role in the proliferation of HCC cells. LXR-miR-124-3p-cyclin D1/CDK6 pathway may be a novel potential therapeutic target for HCC treatment.

Objectives Long non-coding RNA H19 (lncRNA-H19) is highly expressed in fibroblast-like synoviocytes (FLS) from patients with RA. The present study aimed to clarify the pathological significance and regulatory mechanisms of lncRNA-H19 in FLS. Methods Mice with CIA were locally injected with LV-shH19. The progression of CIA was explored by measuring arthritic index (AI), paw thickness (PT) and histologic analysis. The growth and cell cycle of human synoviocyte MH7A were assessed by CCK-8 and flow cytometric analysis. The putative binding sites between lncRNA-H19 and miR-124a were predicted online, and the binding was identified by luciferase assay. RT-qPCR, Western blot and luciferase assay were performed to explore the molecular mechanisms between liver X receptor (LXR), lncRNA-H19, miR-124a and its target genes. Results The expression of lncRNA-H19 was closely associated with the proliferation of synoviocytes and knockdown of lncRNA-H19 significantly ameliorated the progression of CIA, reflected by decreased AI, PT and cartilage destruction. Notably, lncRNA-H19 competitively bound to miR-124a, which directly targets CDK2 and MCP-1. It was confirmed that lncRNA-H19 regulates the proliferation of synoviocytes by acting as a sponge of miR-124a to modulate CDK2 and MCP-1 expression. Furthermore, the agonists of LXR inhibited lncRNA-H19-mediated miR-124a-CDK2/MCP-1 signalling pathway in synoviocytes. The ‘lncRNA-H19-miR-124a-CDK2/MCP-1’ axis plays an important role in LXR anti-arthritis. Conclusion Regulation of the miR-124a-CDK2/MCP-1 pathway by lncRNA-H19 plays a crucial role in the proliferation of FLS. Targeting this axis has therapeutic potential in the treatment of RA and may represent a novel strategy for RA treatment.

Additional file 8: Figure S3. Restoration of FOXO1 and FOXO3a Partially Reversed CircMRPS35-Induced Suppression of Gastric Cancer Progression. Related to Fig. 5. Figure S4. Molecular Docking of the Interactions of CircMRPS35/KAT7/H4K5ac and the Design of ChIP Primers. Related to Fig. 7

Additional file 11: Animal Ethic Statement

Additional file 6: Figure S1. The Validation of Differentially Expressed CircRNAs in 30 pairs of Gastric Cancer Tissues and the Paracancer Tissues

Additional file 7: Figure S2. CircMRPS35 Knockdown Promotes MKN45 Cells Proliferation and Metastasis in vitro. Related to Fig. 3

Metabolic reprogramming greatly contributes to the regulation of macrophage activation. However, the mechanism of lipid accumulation and the corresponding function in tumor-associated macrophages (TAMs) remain unclear. With primary investigation in colon cancer and confirmation in other cancer models, here we determine that deficiency of monoacylglycerol lipase (MGLL) results in lipid overload in TAMs. Functionally, macrophage MGLL inhibits CB2 cannabinoid receptor-dependent tumor progression in inoculated and genetic cancer models. Mechanistically, MGLL deficiency promotes CB2/TLR4-dependent macrophage activation, which further suppresses the function of tumor-associated CD8+ T cells. Treatment with CB2 antagonists delays tumor progression in inoculated and genetic cancer models. Finally, we verify that expression of macrophage MGLL is decreased in cancer tissues and positively correlated with the survival of cancer patients. Taken together, our findings identify MGLL as a switch for CB2/TLR4-dependent macrophage activation and provide potential targets for cancer therapy., Tumour associated macrophages (TAMs) have an altered lipid metabolism. Here the authors show that downregulation of monoacylglycerols lipase MGLL in TAMs induces lipid accumulation and tumor progression by polarizing TAMs toward tumor-promoting through activation of cannabinoid receptor CB2.

The BH3 mimetic (-)-gossypol (-)-G has shown promising efficacy to kill several kinds of cancer cells or potentiate current chemotherapeutics. But it induces limited apoptosis in cancer cells with high level of Bcl-2. The nuclear receptor PPARγ and its agonist rosiglitazone can suppress various malignancies. More importantly, rosiglitazone is able to enhance the anti-tumor effects of chemotherapy drugs such as carboplatin and tyrosine kinase inhibitors. In this study, we for the first time demonstrated that rosiglitazone could sensitize (-)-G to induce apoptosis in cancer cells with high level of Bcl-2. Furthermore, we found that (-)-G increased the mRNA level and protein stability of Mcl-1, which weakened the pro-apoptotic effect of (-)-G. Rosiglitazone attenuated the (-)-G-induced Mcl-1 stability through decreasing JNK phosphorylation. Additionally, rosiglitazone upregulated dual-specificity phosphatase 16 (DUSP16), leading to a reduction of (-)-G-triggered JNK phosphorylation. Animal experiments showed that rosiglitazone could sensitize (-)-G to repress the growth of cancer cells with high level of Bcl-2 in vivo. Taken together, our results suggest that the PPARγ agonists may enhance the therapeutic effect of BH3 mimetics in cancers with high level of Bcl-2 through regulating the DUSP16/JNK/Mcl-1 singling pathway. This study may provide novel insights into the cancer therapeutics based on the combination of PPARγ agonists and BH3 mimetics.

// Fan Yang 1, 2, * , Qingjian Wu 3, * , Yan Zhang 1 , Haojun Xiong 1 , Xinzhe Li 1 , Bo Li 1 , Wei Xie 2 , Le Zhang 2 , Min Xu 4 , Kebin Zhang 2 and Fengtian He 1 1 Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Third Military Medical University, Chongqing 400038, China 2 Central Laboratory, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China 3 Department of Urology, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China 4 Center for Disease Control and Prevention, Chengdu Military Region, Chengdu 610021, China * These authors have contributed equally to this work Correspondence to: Fengtian He, email: hefengtian66@163.com Kebin Zhang, email: zhangkebin12@163.com Min Xu, email: 603537726@qq.com Keywords: LOC653786; FOXM1; long noncoding RNA; renal cell carcinoma; cell growth Received: August 02, 2017 Accepted: January 02, 2018 Published: January 08, 2018 ABSTRACT Renal cell carcinoma (RCC) is the most common kidney malignancy with poor prognosis. Recently, long noncoding RNAs (lncRNAs) have been demonstrated as important regulators in multiple cancers including RCC. LOC653786 is a lncRNA, but its role in cancer remains unclear. In this study, we for the first time found that LOC653786 was upregulated in RCC tissues and cell lines, and this lncRNA promoted growth and cell cycle progression of RCC cells. Moreover, we showed that LOC653786 elevated the expression of forkhead box M1 (FOXM1) and its downstream target genes cyclin D1 and cyclin B1 in RCC cells. Reporter assay revealed that LOC653786 enhanced the transcriptional activity of FOXM1 gene promoter. Additionally, knockdown of FOXM1 attenuated the LOC653786-enhanced growth and cell cycle progression of RCC cells. Meanwhile, silencing of LOC653786 suppressed RCC cell growth and cell cycle progression, which was alleviated by overexpression of FOXM1. The in vivo experiments in nude mice showed knockdown of LOC653786 repressed xenograft tumor growth and FOXM1 expression. In conclusion, our results demonstrate that LOC653786 accelerates growth and cell cycle progression of RCC cells via upregulating FOXM1, suggesting that the ‘LOC653786/FOXM1’ pathway may serve as a novel target for RCC treatment.

Considerable evidences have shown that both heat shock transcription factor 1 (HSF1) and autophagy can attenuate the sensitivity of hepatocellular carcinoma (HCC) cells to chemotherapeutic reagents. However, it is still little known whether HSF1 is associated with autophagy in regulating the chemosensitivity of HCC cells. In this study, we for the first time demonstrated that HSF1 markedly attenuated the killing effect of epirubicin (EPI) to HCC cells via enhancing the EPI-induced protective autophagy. Mechanistically, HSF1 upregulated autophagy related 4B (ATG4B) in HCC cells, which enhanced the EPI-triggered protective autophagy. Reporter assay showed that HSF1 increased the transcriptional activity of ATG4B gene promoter, and chromatin immunoprecipitation assay verified that HSF1 bound to the site (−1429 to −1417) in ATG4B gene promoter region. The experiments in nude mice showed that knockdown of HSF1 or ATG4B strengthened the anti-HCC effect of EPI in vivo. Collectively, these results revealed that HSF1 elevates ATG4B via promoting its transcription, which alleviates the sensitivity of EPI in HCC cells through enhancing protective autophagy, suggesting that the “HSF1/ATG4B/protective autophagy” pathway may be a novel target for developing sensitizing strategy to HCC chemotherapy.

miR‐206 plays an important role in regulating the growth of multiple cancer cells. Cyclin‐dependent kinase 9 (CDK9) stimulates the production of abundant prosurvival proteins, leading to impaired apoptosis of cancer cells. However, it is unknown whether CDK9 is involved in the miR‐206‐mediated growth suppression of hepatocellular carcinoma (HCC) cells. In this study, we found that the expression level of miR‐206 was significantly lower in HCC cell lines than that in normal hepatic cell line (L02). Meanwhile, CDK9 was upregulated in HCC cell lines. Moreover, miR‐206 downregulated CDK9 in HCC cells via directly binding to its mRNA 3′ UTR, which resulted in a decrease of RNA PolII Ser2 phosphorylation and Mcl‐1 level. Additionally, miR‐206 suppressed the cell proliferation, and induced cell cycle arrest and apoptosis. Similarly, silence or inhibition of CDK9 also repressed the cell proliferation, and induced cell cycle arrest and apoptosis. Taken together, the results demonstrated that miR‐206 inhibited the growth of HCC cells through targeting CDK9, suggesting that the miR‐206‐CDK9 pathway may be a novel target for the treatment of HCC.

p53 deficiency, a frequent event in multiple kinds of malignancies, decreases the sensitivity of diverse targeted chemotherapeutics including the BCL-XL/BCL-2 inhibitor ABT-263. Loss of p53 function can activate mTOR complex 1 (mTORC1), which may make it a vulnerable target. Metformin has shown anti-neoplastic efficiency partially through suppressing mTORC1. However, it remains unknown whether mTORC1 activation confers ABT-263 resistance and whether metformin can overcome it in the p53-defective contexts. In this study, we for the first time demonstrated that metformin and ABT-263 synergistically elicited remarkable apoptosis through orchestrating the proapoptotic machineries in various p53-defective cancer cells. Mechanistic studies revealed that metformin sensitized ABT-263 via attenuating mTORC1-mediated cap-dependent translation of MCL-1 and survivin and weakening internal ribosome entry site (IRES)-dependent translation of XIAP. Meanwhile, ABT-263 sensitized metformin through disrupting the BCL-XL/BIM complex. However, metformin and ABT-263 had no synergistic killing effect in p53 wild-type (p53-WT) cancer cells because the cotreatment dramatically induced the senescence-associated secretory phenotype (SASP) in the presence of wild type p53, and SASP could aberrantly activate the AKT/ERK–mTORC1–4EBP1–MCL-1/survivin signaling axis. Blocking the axis using corresponding kinase inhibitors or neutralizing antibodies against different SASP components sensitized the cotreatment effect of metformin and ABT-263 in p53-WT cancer cells. The in vivo experiments showed that metformin and ABT-263 synergistically inhibited the growth of p53-defective (but not p53-WT) cancer cells in tumor xenograft nude mice. These results suggest that the combination of metformin and ABT-263 may be a novel targeted therapeutic strategy for p53-defective cancers. Mol Cancer Ther; 16(9); 1806–18. ©2017 AACR.

Highly upregulated in liver cancer (HULC), a lncRNA overexpressed in hepatocellular carcinoma (HCC), has been demonstrated to be involved in the carcinogenesis and progression of HCC. However, the mechanisms of HULC promoting the abnormal growth of HCC cells are still not well elucidated. In the present study, we for the first time demonstrated that HULC promoted the growth of HCC cells through elevating COX-2 protein. Moreover, the study of the corresponding mechanism by which HULC upregulated COX-2 showed that HULC enhanced the level of ubiquitin-specific peptidase 22 (USP22), which decreased ubiquitin-mediated degradation of COX-2 protein by removing the conjugated polyubiquitin chains from COX-2 and finally stabilized COX2 protein. In addition, knockdown of USP22 or COX-2 attenuated HULC-mediated abnormal growth of HCC cells. In conclusion, our results demonstrated that "USP22/COX-2" axis played an important role in HULC promoting growth of HCC cells. The identification of this novel pathway may pave a road for developing new potential anti-HCC strategies.

// Haojun Xiong 1 , Yan Zhang 1 , Shan Chen 1 , Zhenhong Ni 1 , Jintao He 2 , Xinzhe Li 1 , Bo Li 1 , Kai Zhao 1 , Fan Yang 1 , Yijun Zeng 1 , Bingbo Chen 3 and Fengtian He 1 1 Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Third Military Medical University, Chongqing 400038, China 2 Battalion 17 of Students, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China 3 Laboratory Animal Center, Third Military Medical University, Chongqing 400038, China Correspondence to: Fengtian He, email: hefengtian06@aliyun.com Bingbo Chen, email: chenbb81@126.com Keywords: HCC, LXR, SOCS3 Received: April 28, 2017 Accepted: June 10, 2017 Published: July 18, 2017 ABSTRACT Liver X receptor (LXR), a member of nuclear receptor superfamily, is involved in the regulation of glucose, lipid and cholesterol metabolism. Recently, it has been reported that LXR suppress different kinds of cancers including hepatocellular carcinoma (HCC). However, the corresponding mechanism is still not well elucidated. In the present study, we found that activation of LXR downregulated cyclin D1 while upregulated p21 and p27 by elevating the level of suppressor of cytokine signaling 3 (SOCS3), leading to the cell cycle arrest at G1/S phase and growth inhibition of HCC cells. Moreover, we demonstrated that LXRα (not LXRβ) mediated the induction of SOCS3 in HCC cells. Subsequently, we showed that LXR activation enhanced the mRNA stability of SOCS3, but had no significant influence on the transcriptional activity of SOCS3 gene promoter. The experiments in nude mice revealed that LXR agonist inhibited the growth of xenograft tumors and enhanced SOCS3 expression in vivo . These results indicate that “LXRα-SOCS3-cyclin D1/p21/p27” is a novel pathway by which LXR exerts its anti-HCC effects, suggesting that the pathway may be a new potential therapeutic target for HCC treatment.

// Bo Li 1, * , Xinzhe Li 1, * , Haojun Xiong 1 , Peng Zhou 1 , Zhenhong Ni 1 , Teng Yang 1 , Yan Zhang 1 , Yijun Zeng 1 , Jintao He 2 , Fan Yang 1 , Nan Zhang 1 , Yuting Wang 1 , Yingru Zheng 3 and Fengtian He 1 1 Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Third Military Medical University, Chongqing 400038, China 2 Battalion 17 of Students, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China 3 Department of Obstetrics and Gynecology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing 400042, China * These authors have contributed equally to this work Correspondence to: Yingru Zheng, email: zyrdaping@aliyun.com Fengtian He, email: hefengtian06@aliyun.com Keywords: dichloroacetate, COX2, celecoxib, QKI, cervical cancer Received: February 07, 2017 Accepted: May 06, 2017 Published: June 16, 2017 ABSTRACT Dichloroacetate (DCA), a traditional mitochondria-targeting agent, has shown promising prospect as a sensitizer in fighting against malignancies including cervical cancer. But it is unclear about the effect of DCA alone on cervical tumor. Moreover, previous reports have demonstrated that the increased cyclooxygenase-2 (COX2) expression is associated with chemoresistance and poor prognosis of cervical cancer. However, it is still unknown whether COX2 can affect the sensitivity of DCA in cervical cancer cells. In this study, we found that cervical cancer cells were insensitive to DCA. Furthermore, we for the first time revealed that DCA could upregulate COX2 which impeded the chemosensitivity of DCA in cervical cancer cells. Mechanistic study showed that DCA reduced the level of RNA binding protein quaking (QKI), leading to the decay suppression of COX2 mRNA and the subsequent elevation of COX2 protein. Inhibition of COX2 using celecoxib could sensitize DCA in repressing the growth of cervical cancer cells both in vitro and in vivo . These results indicate that COX2 is a novel resistance factor of DCA, and combination of celecoxib with DCA may be beneficial to the treatment of cervical cancer.

Sorafenib is the first‑line drug used in the treatment of liver cancer; however, drug resistance seriously limits the clinical response to sorafenib. The present study investigated the molecular mechanisms of sorafenib resistance in liver cancer cells. The data indicated that forkhead box M1 (FoxM1) was significantly overexpressed in sorafenib‑resistant cells, at the mRNA and protein levels. Knockdown of FoxM1 rendered drug‑tolerant cells sensitive to sorafenib. Furthermore, FoxM1 was upregulated at the transcriptional level. Overexpression of c‑jun was associated with the upregulation of FoxM1. The results of a reporter gene assay, electrophoretic mobility shift assay and chromatin immunoprecipitation assay demonstrated that there is an activator protein‑1 (AP1) binding site in the promoter of FoxM1, located at ‑608 to ‑618. Knockdown of c‑jun significantly decreased the levels of FoxM1, accompanied by enhanced cell sensitivity to sorafenib. Furthermore, the activation of AKT contributed to the upregulation of c‑jun and FoxM1. Inhibition of AKT using BEZ‑235 markedly suppressed the upregulation of c‑jun and FoxM1, and increased the sensitivity of drug‑resistant cells to sorafenib in vitro and in vivo. The data indicated that the activation of the AKT/AP1/FoxM1 signaling axis is an important determinant of sorafenib tolerance.

B cell activating factor (BAFF), a member of the tumor necrosis factor (TNF) family, plays a critical role in the pathogenesis and progression of rheumatoid arthritis (RA). Chlorogenic acid (CGA) is a phenolic compound and exerts antiarthritic activities in arthritis. However, it is not clear whether the anti-inflammatory property of CGA is associated with the regulation of BAFF expression. In this study, we found that treatment of the collagen-induced arthritis (CIA) mice with CGA significantly attenuated arthritis progression and markedly inhibited BAFF production in serum as well as the production of serum TNF-α. Furthermore, CGA inhibits TNF-α-induced BAFF expression in a dose-dependent manner and apoptosis in MH7A cells. Mechanistically, we found the DNA-binding site for the transcription factor NF-κB in the BAFF promoter region is required for this regulation. Moreover, CGA reduces the DNA-binding activity of NF-κB to the BAFF promoter region and suppresses BAFF expression through the NF-κB pathway in TNF-α-stimulated MH7A cells. These results suggest that CGA may serve as a novel therapeutic agent for the treatment of RA by targeting BAFF.

Ethnopharmacological relevance Asian countries, such as China, Japan, and Korea, have witnessed a history of more than 1000 years of Panax notoginseng (Burk.) F.H. Chen's application as a famous traditional medicine for cardiovascular diseases (Zhou et al., 2004). The use of Panax notoginseng (Sanqi) was first recorded in “Bencao Gangmu”, which was written by Li Shizhen, a Chinese pharmacologist of the MING dynasty, in 1578. It is included in “The Plant List” as one species of genus Panax (family Araliaceae). Panax notoginseng saponins (PNS) are the major active ingredients extracted from Panax notoginseng. Aim of the study This study investigated whether PNS and the active constituent Ginsenoside Rb1 inhibits adhesion events by regulating the NF-E2-related factor 2 (Nrf2) – p38 – vascular cell adhesion molecule (VCAM)-1 pathway. Materials and methods The AS model rats were treated once daily with PNS (100 mg/kg, i.p.) or Rb1 (40 mg/kg, i.p.), and pathological changes in the aortas were observed by electron microscopy and Sudan IV staining. The serum levels of NO, superoxide dismutase (SOD) and TNF-α were measured. Upon treatment with H 2 O 2 to induce oxidative stress , cell viability and LDH levels were measured after cells were cultured with PNS or Rb1. oxidized low density lipoprotein (oxLDL)-induced VCAM-1 and p38 protein expression and THP1 cell adhesion to ECs were assessed after treatment with PNS or Rb1. Nuclear translocation of Nrf2 and expression of its target protein heme oxygenase (HO)-1 were observed in the respective presence of PNS or Rb1. Results Upon treatment with PNS or Rb1, pathological changes observed in the aortas of AS model rats were alleviated, and an increase in serum levels of NO and SOD and a decrease in TNF-α levels were observed. In vitro treatment with PNS or Rb1 protected endothelial cells (ECs) from H 2 O 2 -mediated cytotoxicity, suppressed oxLDL-induced p38 and VCAM-1 protein expression and inhibited THP1 cell adhesion to ECs. Finally, PNS and Rb1 treatment functionally activated Nrf2 in ECs. Conclusions Nrf2, an EC protective system, suppresses monocyte adhesion events via the inhibition of the ROS – TNF-α – p38 – VCAM-1 pathway following treatment with PNS, with Rb1 specifically playing an important role among PNS active components.

// Bo Li 1, * , Xinzhe Li 1, * , Zhenhong Ni 1 , Yan Zhang 1 , Yijun Zeng 1 , Xiaohuan Yan 2 , Yan Huang 3 , Jintao He 4 , Xilin Lyu 1 , Yaran Wu 1 , Yuting Wang 1 , Yingru Zheng 2 , Fengtian He 1 1 Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Third Military Medical University, Chongqing 400038, China 2 Department of Obstetrics and Gynecology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing 400042, China 3 Cancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing 400042, China 4 Battalion 17 of Students, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China * These authors have contributed equally to this work Correspondence to: Yingru Zheng, email: zyrdaping@aliyun.com Fengtian He, email: hefengtian06@aliyun.com Keywords: dichloroacetate, metformin, Mcl-1, cancer metabolism, ovarian cancer Received: January 24, 2016 Accepted: July 09, 2016 Published: July 19, 2016 ABSTRACT Both dichloroacetate (DCA) and metformin (Met) have shown promising antitumor efficacy by regulating cancer cell metabolism. However, the DCA-mediated protective autophagy and Met-induced lactate accumulation limit their tumor-killing potential respectively. So overcoming the corresponding shortages will improve their therapeutic effects. In the present study, we found that DCA and Met synergistically inhibited the growth and enhanced the apoptosis of ovarian cancer cells. Interestingly, we for the first time revealed that Met sensitized DCA via dramatically attenuating DCA-induced Mcl-1 protein and protective autophagy, while DCA sensitized Met through markedly alleviating Met-induced excessive lactate accumulation and glucose consumption. The in vivo experiments in nude mice also showed that DCA and Met synergistically suppressed the growth of xenograft ovarian tumors. These results may pave a way for developing novel strategies for the treatment of ovarian cancer based on the combined use of DCA and Met.

Pirarubicin (THP) is a newer generation anthracycline anticancer drug. In the clinic, THP and THP-based combination therapies have been demonstrated to be effective against various tumors without severe side effects. However, previous clinical studies have shown that most patients with cervical cancer are not sensitive to THP treatment, and the associated mechanisms are not clear. Consistent with the clinical study, we confirmed that cervical cancer cells were resistant to THP in vitro and in vivo. Our data demonstrated that THP induced a protective macroautophagy/autophagy response in cervical cancer cells, and suppression of this autophagy dramatically enhanced the cytotoxicity of THP. By scanning the mRNA level change of autophagy-related genes, we found that the upregulation of ATG4B (autophagy-related 4B cysteine peptidase) plays an important role in THP-induced autophagy. Moreover, THP increased the mRNA level of ATG4B in cervical cancer cells by promoting mRNA stability without influencing its transcription. Furthermore, THP triggered a downregulation of MIR34C-5p, which was associated with the upregulation of ATG4B and autophagy induction. Overexpression of MIR34C-5p significantly decreased the level of ATG4B and attenuated autophagy, accompanied by enhanced cell death and apoptosis in THP-treated cervical cancer cells. These results for the first time reveal the presence of a MIR34C-5p-ATG4B-autophagy signaling axis in THP-treated cervical cancer cells in vitro and in vivo, and the axis, at least partially, accounts for the THP nonsensitivity in cervical cancer patients. This study may provide a new insight for improving the chemotherapeutic effect of THP, which may be beneficial to the further clinical application of THP in cervical cancer treatment.

Dexamethasone (Dex) has been commonly used in lymphoma and leukemia treatment, but the detailed mechanisms are not fully understood. Suppressor of AP-1 regulated by interferon (SARI) has tumor-selective growth inhibitory effect. However, it's unclear whether SARI is involved in the Dex-mediated lymphoma growth suppression. In this study, we found that Dex-treated B lymphoma tissues had a higher level of SARI. Dex repressed the growth of B lymphoma cells and upregulated SARI expression by activating glucocorticoid receptor (GR) in vitro and in vivo. Silencing of SARI attenuated the Dex-mediated growth suppression of B lymphoma cells and inhibition of AP-1 activity. Reporter assays revealed that activation of GR enhanced the transcriptional activity of SARI promoter. EMSA and ChIP assays showed that GR directly bound to the ER9 element in SARI promoter region. These results for the first time demonstrated that SARI is a novel target gene of GR, and the upregulation of SARI plays an important role in Dex's killing effect on B lymphoma cells, suggesting that SARI may serve as a novel target and a potential indicator of Dex sensitivity in B lymphoma treatment.