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Multiple myeloma (MM) is an aggressive plasma cell neoplasm characterized by genomic heterogeneity. Superenhancers (SEs) are defined as large clusters of enhancers in close genomic proximity, which regulate genes for maintaining cellular identity and promote oncogenic transcription to which cancer cells highly addicted. Here, we analyzed cis-regulatory elements in MM samples with H3K27ac ChIP-seq, to identify novel SE-associated genes involved in the myeloma pathogenesis. SEs and their associated genes in cancerous tissue were compared with the control samples, and we found SE analysis alone uncovered cell-lineage-specific transcription factors and well-known oncogenes ST3GAL6 and ADM. Using a transcriptional CDK7 inhibitor, THZ1, coupled with H3K27ac ChlP-seq, we identified MAGI2 as a novel SE-associated gene of myeloma cells. Elevated MAGI2 was related to myelomagenesis with gradual increased expression from MGUS, SMM to newly diagnosed and relapsed MM. High prevalence of MAGI2 was also associated with poor survival of MM patients. Importantly, inhibition of the SE activity associated with MAGI2 decreased MAGI2 expression, inhibited cell growth and induced cell apoptosis. Mechanistically, we revealed that the oncogenic transcription factor, MAF, directly bound to the SE region and activated gene transcription. In summary, the discoveries of these acquired SEs-associated genes and the novel mechanism by which they are regulated provide new insights into MM biology and MAGI2-MAF-SE regulatory circuit offer potential novel targets for disease treatment.

Chemoresistance is a daunting challenge to the prognosis of patients with breast cancer. Signal transducer and activator of transcription (STAT) 5a plays vital roles in the development of various cancers, but its function in breast cancer is controversial, and its role in chemoresistance in breast cancer remains unexplored. Here we identified STAT5a as a chemoresistance inducer that regulates the expression of ABCB1 in breast cancer and can be targeted by pimozide, an FDA-approved psychotropic drug. First, we found that STAT5a and ABCB1 were expressed at higher levels in doxorubicin-resistant cell lines and chemoresistant patients, and their expression was positively correlated. Then, we confirmed the essential roles of STAT5a and ABCB1 in doxorubicin resistance in breast cancer cells and the regulation of ABCB1 transcription by STAT5a. Subsequently, the efficacy of pimozide in inhibiting STAT5a and sensitizing doxorubicin-resistant breast cancer cells was tested. Finally, we verified the role of STAT5a in doxorubicin resistance in breast cancer and the efficacy of pimozide in reversing this resistance in vivo. Our study demonstrated the vital role of STAT5a in doxorubicin resistance in breast cancer. Targeting STAT5a might be a promising strategy for treating doxorubicin-resistant breast cancer. Moreover, repurposing pimozide for doxorubicin resensitization is attractive due to the safety profile of pimozide.

Background Adriamycin (ADM) is currently one of the most effective chemotherapeutic agents in breast cancer treatment. However, growing resistance to ADM can lead to treatment failure and poor outcome. The underlying molecular mechanisms in ADM resistance in breast cancer remains unclear. PLAC8 is reported as a novel highly-conserved protein and functions as an oncogene or tumor suppressor in various tumors. Methods Here, we analyzed the expression profile of PLAC8 in breast cancer tissues and breast cancer cell lines, and explored the correlation of PLAC8 expression levels with patients’ outcomes and ADM response. One ADM resistant MCF-7 breast cancer cell (MCF-7/ADM) and its parental cell was used as in vitro models to identify the underlying mechanism of PLAC8 and ADM resistance. Breast cancer cells were transfected with PLAC8 knockdown and overexpression vectors, and MTT and colony formation assays were performed to test the cell response to ADM. Then, we tested the effect of PLAC8 on autophagy pathway by flow cytometry and immunofluorescence analysis, and the change of main autophagy-correlated factors expressions: LC3 and p62. Next, combining treatment of autophagy inhibitor/inducer and PLAC8 downregulation/upregulation revealed the participation of PLAC8 in autophagy pathway to synergistically regulate ADM resistance in breast cancer. Results Here, higher PLAC8 expression was correlated with poorer outcome and aggressive phenotype in breast cancer, and breast cancer patients with higher PLAC8 expression showed potential ADM resistance. PLAC8 expression level was also significantly elevated in ADM resistant MCF-7 breast cancer cells (MCF-7/ADM), compared to parental MCF-7 cells. In vitro experiments further confirmed that PLAC8 inhibition by siRNA or enforced overexpression by infecting pcDNA3.1(C)-PLAC8 plasmid correspondingly decreased or increased the ADM resistance. Subsequently, we demonstrated that ectopic PLAC8 expression in MCF-7/ADM cell blocked the accumulation of the autophagy-associated protein LC3II, and resulted in cellular accumulation of p62. Rapamycin-triggered autophagy significantly increased cell response to ADM, while the autophagy inhibitor 3-MA enhanced ADM resistance. Actually, 3-MA and PLAC8 could synergistically enhance ADM resistance via blocking the autophagy process. Additionally, the downregulation of p62 by siRNA attenuated the activation of autophagy and PLAC8 expression in breast cancer cells. Conclusion Our findings suggest that PLAC8, through participation of p62, inhibits autophagy and consequently results in ADM resistance in breast cancer. PLAC8/p62/autophagy pathway may act as novel therapeutic targets in breast cancer treatment and has potential clinical application in overcoming ADM resistance.

Tamoxifen resistance represents a daunting challenge to the successful treatment for breast cancer. Krüppel-like factor 4 has critical roles in the development and progression of breast cancer, but its expression, function and regulation in the efficacy of TAM therapy in breast cancer have yet to be investigated. Here, we examined the clinical significance and biologic effects of KLF4 in breast cancer. Firstly, higher expression of KLF4 correlated with increased TAM sensitivity in breast cancer cells, and analysis of GEO datasets indicated that KLF4 expression was positively correlated with ERα and enhanced expression of KLF4 sensitized breast cancer patients to endocrine therapy. Knockdown of KLF4 in MCF-7 and BCAP37 cells led to increased TAM resistance, while ectopic KLF4 expression promoted the responsiveness to TAM in T47D and TAM-resistant MCF-7/TAM cells. Secondly, ectopic KLF4 overexpression suppressed MCF-7/TAM cell growth, invasion and migration. Moreover, KLF4 expression was down-regulated in breast cancer tumor tissues and high expression of KLF4 was associated with favorable outcomes. Mechanistically, KLF4 may enhance the responsiveness of breast cancer cells to TAM through suppressing mitogen-activated protein kinase (MAPK) signaling pathway. We found that ERK and p38 were more activated in MCF-7/TAM compared with MCF-7, and treatment with MAPK-specific inhibitors significantly suppressed cell viability. Knockdown of KLF4 activated ERK and p38 and drove MCF-7 cells to become resistant to TAM. Conversely, overexpression of KLF4 in MCF-7/TAM cells suppressed ERK and p38 signaling and resulted in increased sensitivity to TAM. Therefore, our findings suggested that KLF4 contributed to TAM sensitivity in breast cancer via phosphorylation modification of ERK and p38 signaling. Collectively, this study highlighted the significance of KLF4/MAPK signal interaction in regulating TAM resistance of breast cancer, and suggested that targeting KLF4/MAPK signaling may be a potential therapeutic strategy for breast cancer treatment, especially for the TAM-resistant patients.

Matrix metalloproteinase-1 (MMP1) is a member of the matrix metalloproteinases family, and its aberrant expression is implicated in tumor invasion and metastasis. However, the relationship between MMP1 abnormal expression and clinical outcome in breast cancer patients remains to be elucidated. To address this issue, we conducted immunohistochemistry in breast cancer and adjacent normal tissues, and mined the transcriptional and survival data of MMP1 in breast cancer patients through Oncomine, Kaplan-Meier Plotter, bc-GenExMiner, COSMIC and cBioPortal databases. First, we found that both protein and mRNA levels of MMP1 expression were significantly higher in breast cancer tissues. Second, high MMP1 mRNA expression correlated with worse overall survival among grade II (HR = 1.75; p = 0.011), nodal-negative (HR = 2.00; p = 0.00028), ER-positive (HR = 1.61; p = 0.00027) and HER2-negative (HR = 3.17; p = 0.029) patients with breast cancer by using Kaplan-Meier plotter database. Third, the overexpression of MMP1 was associated with unfavorable survival results including overall survival (HR = 1.6; p = 1.6e-05), relapse free survival (HR = 1.78; p < 1e-16) and distant metastasis free survival (HR = 1.65; p = 5.3e-05) in patients with breast cancer. Taken together, the expression status of MMP1 is a significant prognostic indicator and a potential drug target for breast cancer.

// Xiao Luo 1, * , Yerfan Jiaerken 1, * , Xinfeng Yu 1 , Peiyu Huang 1 , Tiantian Qiu 1 , Yunlu Jia 3 , Kaicheng Li 1 , Xiaojun Xu 1 , Zhujing Shen 1 , Xiaojun Guan 1 , Jiong Zhou 2 and Minming Zhang 1 , for The Alzheimer’s Disease Neuroimaging Initiative (ADNI) 1 Department of Radiology, The Second Affiliated Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China 2 Department of Neurology, The Second Affiliated Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China 3 Department of Surgical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, China * These authors have contributed equally to this work Correspondence to: Minming Zhang, email: zhangminming@zju.edu.cn Keywords: apolipoprotein E (APOE), cerebral small-vascular disease (CSVD), white matter hyperintensities (WMH), dilated perivascular space (dPVS), cognition Abbreviations: APOE: apolipoprotein E; CSVD: cerebral small-vascular disease; WMH: white matter hyperintensities; dPVS: dilated perivascular space; MBs: microbleeds Received: December 29, 2016 Accepted: April 07, 2017 Published: May 09, 2017 ABSTRACT Objective: It remains unclear if and how the interactions between APOE genotypes and cerebral small-vessel diseases (CSVD) lead to cognitive decline in the long term. Based on ADNI cohort, this longitudinal study aimed to clarify the potential relationship among APOE genotype, CSVD and cognition by integrating multi-level data. Method: There were 135 healthy elderly (including e2, e4 allele carriers and e3 homozygotes) who had completed two years’ follow-up. MRI markers of CSVD, including white matter hyperintensities (WMH), dilated perivascular space (dPVS), microbleeds and lacune, were assessed. Besides, neuropathological factors including Alzheimer’s disease-related pathology measured by CSF and PiB-PET were assessed. Repeated measurements ANOVAs were performed to test impact of different APOE genotypes on CSVD. Results: We found that APOE e4 carriers had significantly more frontal WMH burden and basal ganglia dPVS at baseline and faster progression of frontal WMH burden during follow-up. Furthermore, our results showed that APOE e4 carriers had significantly decreased Aβ 1-42 level, and its level was negatively related with baseline and progressive total WMH burden. Then, general linear modals indicated interaction between basal frontal WMH burden and e4 allele was related with declining trend of cognition. Conclusion: Our findings suggested APOE e4 allele was associated with increased Aβ deposition, which may lead to the formation and progression of WMH, especially in frontal lobe. Besides, interaction between the increased frontal WMH burden and e4 allele can exert long-term detrimental effects on individual’s trajectory of cognition.

// Hanchu Xiong 1,2,* , Wenhe Zhao 1,2,* , Ji Wang 1,2,* , Benjamin J. Seifer 3 , Chenyang Ye 4 , Yongxia Chen 1,2 , Yunlu Jia 1,2 , Cong Chen 1,2 , Jianguo Shen 1,2 , Linbo Wang 1,2 , Xinbing Sui 2,5 and Jichun Zhou 1,2 1 Department of Surgical Oncology, Sir Run Run Shaw Hospital, Zhejiang University, Hangzhou, Zhejiang, China 2 Biomedical Research Center and Key Laboratory of Biotherapy of Zhejiang Province, Hangzhou, Zhejiang, China 3 USF Health Morsani College of Medicine, Tampa, FL, USA 4 Cancer Institute (Key Laboratory of Cancer Prevention & Intervention, National Ministry of Education), Second Affiliated Hospital, Zhejiang University, Hangzhou, Zhejiang, China 5 Department of Medical Oncology, Sir Run Run Shaw Hospital, Zhejiang University, Hangzhou, Zhejiang, China * These authors have contributed equally to this work Correspondence to: Linbo Wang, email: // Xinbing Sui, email: // Jichun Zhou, email: // Keywords : Lin28; Let-7; breast cancer; metastasis; drug resistance Received : November 09, 2016 Accepted : January 11, 2017 Published : January 29, 2017 Abstract The RNA binding protein Lin28 is best known for the critical role in cell development, recent researches also have implied its oncogenic function in various human cancers, including breast cancer. Specifically, aberrant Lin28 participates in multiple pathological processes, such as proliferation, metastasis, radiotherapy and chemotherapy resistance, metabolism, immunity and inflammation as well as stemness. In this review, we summarize the let-7-dependent and let-7-independent mechanism regulated by Lin28, focusing on its relation with tumor hallmarks in breast cancer, and subsequently discuss our present knowledge of Lin28 to develop a molecular-based therapeutic strategy against breast cancer.

Background Tamoxifen resistance remains a clinical challenge for hormone receptor-positive breast cancer. Recently, dysregulations in autophagy have been suggested as a potential mechanism for tamoxifen resistance. Although the long noncoding RNA H19 is involved in various stages of tumorigenesis, its role in tamoxifen resistance remains unknown. Here, we assessed the role of H19 in the development of tamoxifen-resistant breast cancer. Methods Quantitative real-time PCR analyzed expression of H19 in tamoxifen-resistant breast cancer tissues. Knockdown of H19 was used to assess the sensitivity to tamoxifen in vitro and in vivo. Both knockdown and overexpression of H19 were used to analyze the status of autophagy. Real-time quantitative methylation-specific polymerase chain reaction, chromatin immunoprecipitation, immunofluorescence, and Western blot were used to explore the tamoxifen resistance mechanism of H19. Results In this study, we observed that the expression of H19 was substantially upregulated in tamoxifen-resistant breast cancer cell line and tumor tissues, and knockdown of H19 enhanced the sensitivity to tamoxifen both in vitro and in vivo. Furthermore, knockdown of H19 significantly inhibited autophagy in MCF7 tamoxifen-resistant (MCF7/TAMR) cells. Conversely, overexpression of H19 promoted autophagy. Interestingly, overexpression of H19 in MCF7 tamoxifen-sensitive cells could recapitulate tamoxifen resistance. Moreover, an increase in methylation in the promoter region of Beclin1 was observed in MCF7/TAMR-shH19 cells. In the double knockdown groups, both shH19+shSAHH and shH19+shDNMT3B rescued the Beclin1 promoter region methylation levels and reactivated autophagy functions. A chromatin immunoprecipitation assay further validated that DNMT3B binds to the Beclin1 promoter region and the knockdown of H19 increases this binding. Conclusions Our findings demonstrate that H19 induces autophagy activation via the H19/SAHH/DNMT3B axis, which could contribute to tamoxifen resistance in breast cancer. Electronic supplementary material The online version of this article (10.1186/s13045-019-0747-0) contains supplementary material, which is available to authorized users.

Background: Extranodal natural killer/T-cell lymphoma (NKTL) is an EBV associated, aggressive malignancy. Activation of JAK/STAT pathway, overexpression of EZH2, and alternations in epigenetic program have been implicated in the pathogenesis of NKTL. Combined chemotherapy-radiotherapy is standard treatment for NKTL patients, but often associated with high relapse rate and serious side effects. New drugs, including anti-PD1 antibody pembrolizumab, have been explored. Overall, treatment for NKTL patients remains challenge in clinic. Super-enhancers (SEs) are defined as large clusters of cis-acting enhancers, marked by high level bindings of acetylation of histone H3 lysine 27 (H3K27ac), coactivators and transcription factors. SE associated oncogenes have been demonstrated to play key roles in various types of cancers. In this study, we aim to define the SE landscapes of NKTL for a better understanding of the molecular pathogenesis of NKTL and to identify novel therapeutic targets. Methods: We performed H3K27Ac ChIP-seq and RNA-seq on primary NKTL tumor samples and paired normal tonsil tissues as controls, then the Rank Ordering of Super Enhancers (ROSE) analysis was used to systematically annotate SEs and their associated genes between tumors and controls. A combination of RNA interference (RNAi), CRISPRi (dCas9-KRAB) technologies and overexpression experiments, followed by several functional assays were performed to determine the effects of candidate SE-genes on NKTL cells. Circularized chromatin conformation capture followed by sequencing (4C-seq) experiments which examine the direct contact of SE and its promoter are ongoing. Results: A total of 1266 SEs were identified in more than 2 out of 3 primary NKTL tumors but not in their normal tonsils. RNA-seq revealed overexpression of 1478 genes (false discovery rate Conclusions: Taken together, our integrative approaches defined the landscape of SE and identified high-value SE-associated oncogenes in NKTL. Among them, we demonstrated that TOX2 is a novel tumor driver, which promotes NKTL cell growth and enhances ability of colony formation, as well as protects cell viability under adverse condition. This study not only provides novel insight into the NKTL pathology, but also offer novel, potential therapeutic targets, such as TOX2 for the treatment of NKTL patients. Disclosures Lim: National Cancer Centre Singapore: Current Employment. Chng:Abbvie: Honoraria; Janssen: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Novartis: Honoraria; Amgen: Honoraria, Research Funding.

Cong Chen,1,2 Shumin Huang,3 Aihua Huang,2,4 Yunlu Jia,1,2 Ji Wang,1,2 Zeqin Zhang,1,2 Misha Mao,1,2 Linbo Wang,1,2 Jichun Zhou1,2 1Department of Surgical Oncology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China; 2Biomedical Research Center and Key Laboratory of Biotherapy of Zhejiang Province, Hangzhou, China; 3The Children’s Hospital, Zhejiang University School of Medicine, Hangzhou, China; 4Department of Pathology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China Background: Ductal carcinoma in situ with microinvasion (DCISM) represents ~1% of all breast cancer cases. Risk factors for lymph node (LN) metastasis and appropriate adjuvant therapy for DCISM are still widely debated. Methods: We retrieved DCISM data from the National Cancer Institute’s Surveillance, Epidemiology, and End Results registry database (1998–2013). Chi-squared tests and logistic regression models were applied to investigate the potential risks of LN metastasis. Univariate and multivariate Cox proportional hazards regressions were performed to estimate the prognostic factors of DCISM. Survival outcomes were estimated using the Kaplan–Meier method. A 1:1 propensity score matching was used to minimize potential bias. Results: Overall, 6,219 patients with DCISM met our inclusion criteria. Younger age and higher grade disease were identified as risk factors for LN metastasis. In the multivariable analysis, LN metastasis and chemotherapy were prognostic factors for worse overall survival and breast cancer-specific survival. Furthermore, propensity score matching and subgroup analysis showed that chemotherapy may not be effective for DCISM patients. Conclusion: Younger patients with high-grade disease tend to have LN involved in DCISM. Adjuvant chemotherapy might not be necessary for patients with DCISM. Keywords: SEER database, breast cancer, ductal carcinoma in situ with microinvasion, adjuvant chemotherapy, lymphatic metastasis

Cong Chen,1,2 Shumin Huang,3 Aihua Huang,1,2 Yunlu Jia,1,2 Ji Wang,1,2 Misha Mao,1,2 Jichun Zhou,1,2 Linbo Wang1,2 1Department of Surgical Oncology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China; 2Biomedical Research Center and Key Laboratory of Biotherapy of Zhejiang Province, Hangzhou, China; 3Department of Pediatric Health Care, The Children’s Hospital, Zhejiang University School of Medicine, Hangzhou, China Background: Despite the considerable experience gained thus far using endoscopic technologies, the role of total endoscopic thyroidectomy (ET) for papillary thyroid cancer (PTC) remains controversial. We conducted a systematic review and meta-analysis to investigate the safety and effectiveness of total ET compared with conventional open thyroidectomy (OT) in PTC. Methods: A systematic search was conducted using the PubMed, Embase and Cochrane Library electronic databases up to March 2018. The quality of included studies was evaluated using the Newcastle–Ottawa Scale. Review Manager software version 5.3 was used for the meta-analysis. Results: Twelve studies including 2,672 patients were ultimately included in the systematic review and meta-analysis. ET was associated with longer operative time (P

Accumulating evidence suggests that placenta-specific 8 (PLAC8) plays an important role in normal cellular process and human diseases, including multiple types of human tumors, and its role is highly relied upon in cellular and physiologic contexts. However, there are no reports on its expression profile and biological roles during lung cancer development. In the current study, both the clinical implications and biological effects of PLAC8 in lung cancer (LC) progression were investigated, and we identified and described the novel Krüppel-like factor 4 (KLF4)/PLAC8 regulatory pathway in cancer progression. Elevated PLAC8 levels were positively correlated with tumor size, histological grade, and tumor node metasis (TNM) stage, and LC patients with high PLAC8 expression suffered poor outcomes. In vitro and in vivo assays further revealed that endogenous PLAC8 promoted cell proliferation and tumor formation. We also found downregulated PLAC8 protein in several LC cell lines following the induction of KLF4, and immunohistochemistry analysis of LC tissues by microarray indicated a potential inverse correlation between PLAC8 and KLF4 expression. Luciferase reporter analysis and chromatin immunoprecipitation assays determined that KLF4 negatively regulated PLAC8 promoter activity via directly binding to the promoter region. Furthermore, the growth inhibition resulting from KLF4 overexpression was partially rescued by ectopic PLAC8 expression. Together, our data uncovered a previously unidentified role of PLAC8 as a central mediator in LC progression. PLAC8 was transcriptionally repressed by KLF4, and the novel KLF4/PLAC8 axis may act as a promising candidate target for LC diagnosis and therapy.

Cyclooxygenase-2 (COX-2) plays an important role in lung cancer development and progression. Using streptavidin-agarose pulldown and proteomics assay, we identified and validated Ku80, a dimer of Ku participating in the repair of broken DNA double strands, as a new binding protein of the COX-2 gene promoter. Overexpression of Ku80 up-regulated COX-2 promoter activation and COX-2 expression in lung cancer cells. Silencing of Ku80 by siRNA down-regulated COX-2 expression and inhibited tumor cell growth in vitro and in a xenograft mouse model. Ku80 knockdown suppressed phosphorylation of ERK, resulting in an inactivation of the MAPK pathway. Moreover, CBP, a transcription co-activator, interacted with and acetylated Ku80 to co-regulate the activation of COX-2 promoter. Overexpression of CBP increased Ku80 acetylation, thereby promoting COX-2 expression and cell growth. Suppression of CBP by a CBP-specific inhibitor or siRNA inhibited COX-2 expression as well as tumor cell growth. Tissue microarray immunohistochemical analysis of lung adenocarcinomas revealed a strong positive correlation between levels of Ku80 and COX-2 and clinicopathologic variables. Overexpression of Ku80 was associated with poor prognosis in patients with lung cancers. We conclude that Ku80 promotes COX-2 expression and tumor growth and is a potential therapeutic target in lung cancer.

Plastic particles have been proven to be abundant in the aquatic environment, raising concerns about their potential toxic effects. In the present study, we determined the bioaccumulation potential of bisphenol A (BPA) in adult zebrafish (Danio rerio) in the absence and presence of nano-sized plastic particles (nanoplastics, NPPs). Results show that BPA can accumulate in the viscera, gill, head and muscle of zebrafish with 85, 43, 20, and 3 μg/g ww after 1 d exposure. NPPs were also found to accumulate in different tissues of the fish. Relative equilibrium was reached after 1 d exposure in different tissues with 39 to 636 mg/kg ww. Co-exposure of NPPs and BPA led to a 2.2 and 2.6-fold significant increment of BPA uptake in the head and viscera, if compared with BPA alone treatment after 3 d exposure. As such, we further investigated several neurotoxic biomarker alterations in the fish head. It was found that either BPA or NPPs can cause myelin basic protein (MBP)/gene up-regulation in the central nervous system (CNS); meanwhile, both contaminants exhibited significant inhibition of acetylcholinesterase (AChE) activity, which is a well-known representative biomarker for neurotoxicity. Moreover, for the co-exposure treatment, biomarkers of myeline and tubulin protein/gene expressions, dopamine content, and the mRNA expression of mesencephalic astrocyte derived neurotrophic factor (MANF) were all significantly up-regulated, suggesting that an enhanced neurotoxic effects in both CNS and dopaminergic system occurred. However, AChE activity was no more inhibited in the co-exposure treatment, which implies that solely AChE measurement may not be sufficient to identify neurotoxic effects in the cholinergic system. Overall, the present study demonstrates that the presence of NPPs can increase BPA bioavailability and cause neurotoxicity in adult zebrafish.

Background: Multiple myeloma (MM) is an aggressive neoplastic plasma cell cancer characterized by diversely cytogenetic abnormalities. MM can be divided into subtypes with immunoglobulin heavy chain (IGH) gene translocations involving CCND1-3, FGFR3/MMSET, MAFs and hyperdiploid myeloma containing trisomies of several odd numbered chromosomes 3, 5, 7, 9, 11, 15, 19, and 21. Although several new drugs have been introduced into clinic, treatment for MM patients remains challenge and refractory/resistant to therapy is often seen. Thus, a better understanding of the molecular pathogenesis of MM can lead to generate new prognostic classification and identify new therapeutic targets. Super-enhancers (SEs) are defined as large clusters of cis-acting enhancers, marked by high level bindings of acetylation of histone H3 lysine 27 (H3K27ac) and mediator complex. SEs have been shown to control genes for maintaining cellular identity and also key tumor drivers in various malignancies. Methods: H3K27Ac ChIP-seq and RNA-seq were performed on primary MM patient samples, MM cell lines. Normal plasma cells and lymphoma cell lines were served as controls. We systematically compared SEs and their associated genes of normal and cancerous tissue. THZ1, a CDK7 inhibitor, was used to efficiently down-regulate SE-associated genes. Combinatory analysis of THZ1-sensitive and SE-associated gene revealed a number of promising MM oncogenes. CRISPR/Cas9 technology and ectopic expression experiments in conjunction with cellular functional assays were performed to determine the effects of candidate SE-genes on MM cells. Circularized chromatin conformation capture followed by sequencing (4C-seq) was applied to explore the direct contact of SE and promoter. Results: SE analysis uncovered some cell lineage-specific transcription factors (TFs) and known oncogenes in MM. Several key TFs, including IRF4, PRDM1, MYC and XBP1, were identified in most MM samples, confirming the origin of MM cells. These data reinforce the concept that SE establishment is a key component of MM biology. The acquisition of SEs around oncogene drivers is widely observed during tumorigenesis. ST3GAL6 and ADM were two known oncogenic drivers in myeloma cells, which were associated with super-enhancers in all MM samples but not in normal plasma cell and lymphoma cells. We also found SE constituents for multiple subtype-specific key oncogenes such as CCND1 in t(11;14) cells, C-MAF in t(14;16) cells, and NSD2 and FGFR3 in t(4;14) cells. Furthermore, THZ1 showed prominent anti-neoplastic effect against MM cells. SE-associated genes were more sensitive to THZ1 compared with those genes associated with typical enhancers (TEs). By overlapping THZ1-sensitve gene with SE-associated genes, we identified a number of novel MM oncogenes, including MAGI2, EDEM3, HJURP, LAMP5, MBD1 and UCK2 as a potential druggable kinase. The expression level of MAGI2 and HJURP confers poor prognosis in several MM datasets. MAGI2 silencing in MM cells decreased cell proliferation and induced apoptosis. qRT-PCR and Western blot analysis confirmed the overexpression of HJURP in t(4;14) cells relative to non-t(4;14) MM cells. Furthermore, 4C-seq analysis revealed the physical interaction between HJURP-SE and promoter and THZ1 treatment diminished this interaction. Motif search at SE constituents revealed a highly significant enrichment of NSD2 recognition. Significant reduction of NSD2 binding at HJURP-SE region was observed in KMS11 infected with NSD2-specific shRNAs. Interestingly, blocking SE sites by CRISPR/Cas9i or silencing HJURP by shRNA led to decreased HJURP expression and cell apoptosis, whereas overexpression of this gene promoted cell growth. Taken together, our data demonstrated that HJURP is a novel SE-associated oncogene in t(4;14) MM. Conclusions: Our integrative approaches by combing H3K27Ac ChIP-seq, RNA-seq and THZ1-sensitive transcript defined the landscape of SE and identified SE-associated novel oncogenes, as well as lineage-specific TFs in MM. Furthermore, we also revealed subtype-specific SE-driving oncogenic program in MM. Taken together, these results not provide novel insight into the MM pathology, but also offer novel, potential therapeutic targets, such as MAGI2, and HJURP for the treatment of MM patients. Disclosures No relevant conflicts of interest to declare.

Apolipoprotein E (APOE) e4 allele is the best established genetic risk factor for sporadic Alzheimer’s disease (AD). However, there is a need to understand the effects of this genotype on the brain by simultaneously assessing intrinsic brain network and cerebral spinal fluid (CSF) biomarkers changes in healthy older e4 carriers. Thirteen cognitively intact, elderly APOE e4 carriers and 22 e3 homozygotes were included in the present study. Eigenvector centrality mapping (ECM) was used to identify brain network hub organization based on resting-state functional MRI (rsfMRI). We evaluated comprehensive cognitive ability and tested levels of Aβ1–42, total-tau (t-tau) and phosphorylated-tau (p-tau181) in CSF. Comparisons of ECM between two groups were conducted, followed by correlations analyses between EC values with significant group differences and cognitive ability/CSF biomarkers. APOE e4 carriers showed significantly decreased EC values in left medial temporal lobe (MTL), left lingual gyrus (LG) and increased EC values in left middle frontal gyrus (MFG) as compared to non-carriers. Correlation analysis demonstrated that left LG EC value correlated with Rey Auditory Verbal Learning Test total learning (RAVLT, r = 0.57, p

APOE is one of the strongest genetic factors associated with information processing speed (IPS). Herein, we explored the neural substrates underlying APOE-related IPS alteration by measuring lobar distribution of white matter hyperintensities (WMH), cortical grey matter volume (GMV) and thickness. Using the ADNI database, we evaluated 178 cognitively normal elderly individuals including 34 APOE e2 carriers, 54 APOE e4 carriers and 90 e3 homozygotes. IPS was determined using Trail Making Tests (TMT). We quantified lobar distribution of WMH, cortical GM lobar volume, cortical thickness among three groups. Finally, we used Pearson's correlation and general linear models to examine structural MRI markers in relation to IPS. There were significant differences of IPS among groups, with e4 carriers displaying the worst performance. Across groups, significant differences in frontal and parietal WMH load were observed (the highest in e4 carriers); however, no significant differences in cortical GMV and thickness were found. Pearson's correlation analysis showed parietal WMH volume was significantly related with IPS, especially in e4 carriers. Subsequently a general linear model demonstrated that parietal WMH volume, age and the interaction between parietal WMH volume and age, was significantly associated with IPS, even after adjusting total intracranial volume (TIV), gender and vascular risk factors. Disruption of WM structure, rather than atrophy of GM, plays a more critical role in APOE e4 allele-specific IPS. Moreover, specific WMH loci are closely associated with IPS; increased parietal WMH volume, especially in e4 carriers, was independently contributed to slower IPS.

// Wenxian Hu 1, * , Yunlu Jia 1, * , Xiangsheng Xiao 2 , Kezhen Lv 3 , Yongxia Chen 1 , Linbo Wang 1 , Xiao Luo 1 , Tianze Liu 2 , Wenbin Li 2 , Yixin Li 2 , Changlin Zhang 2 , Zhenglong Yu 4 , Wenlin Huang 2, 5 , Bing Sun 4 , Wu-guo Deng 2, 5 1 Department of Surgical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, China 2 Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Guangzhou, China 3 Department of Breast Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China 4 Department of Thoracic Surgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China 5 State Key Laboratory of Targeted Drug for Tumors of Guangdong Province, Guangzhou Double Bioproduct Inc., Guangzhou, China * These authors contributed equally to this work Correspondence to: Wenxian Hu, email: 13967169904@163.com Bing Sun, email: dysunbing@163.com Wu-guo Deng, email: dengwg@sysucc.org.cn Keywords: KLF4, hTERT, MAPK, lung cancer, cancer prognosis Received: January 07, 2016 Accepted: April 16, 2016 Published: May 02, 2016 ABSTRACT Kruppel-like factor 4 (KLF4) is a transcription factor that contributes to diverse cellular processes and serves as a tumor suppressor or oncogene in various cancers. Previously, we have reported on the tumor suppressive function of KLF4 in lung cancer; however, its precise regulatory mechanism remains elusive. In this study, we found that KLF4 negatively regulated hTERT expression and telomerase activity in lung cancer cell lines and a mouse model. In addition, the KLF4 and hTERT expression levels were significantly related to the clinicopathological features of lung cancer patients. Promoter reporter analyses revealed the decreased hTERT promoter activity in cells infected with Ad-KLF4, and chromatin immunoprecipitation analysis demonstrated that endogenous KLF4 directly bound to the promoter region of hTERT. Furthermore, the MAPK signaling pathway was revealed to be involved in the KLF4/hTERT modulation pathway. Forced expression of KLF4 profoundly attenuated lung cell proliferation and cancer formation in a murine model. Moreover, hTERT overexpression can partially rescue the KLF4-mediated suppressive effect in lung cancer cells. Taken together, these results demonstrate that KLF4 suppresses lung cancer growth by inhibiting hTERT and MAPK signaling. Additionally, the KLF4/hTERT/MAPK pathway is a potential new therapeutic target for human lung cancer.

Krüppel-like factor 4 (KLF4) has critical roles in breast cancer development and progression and several solid tumors. Tamoxifen (TAM) resistance represents a daunting challenge to the successful treatment of breast cancer. KLF4 expression, function, and regulation in the efficacy of TAM therapy in breast cancer have yet to be demonstrated. Here, we investigated the clinical significance and biologic effects of KLF4 in breast cancer. Firstly, higher expression of KLF4 was correlated with increased TAM sensitivity in breast cells, and analysis of GEO datasets indicated that KLF4 expression was positively correlated with ERa and enhanced expression of KLF4 sensitized breast cancer patients to endocrine therapy. Knockdown of KLF4 in MCF-7 and BCAP37 cells led to increased TAM resistance, while ectopic KLF4 expression promoted the responsiveness of MCF-7/TAM and T47D cells to TAM. Secondly, ectopic KLF4 overexpression suppressed MCF-7/TAM cell growth, invasion, and migration ability. Besides, KLF4 expression was downregulated in breast cancer tumor tissues and high expression of KLF4 linked to favorable outcome. Mechanistically, KLF4 may enhance the responsiveness of breast cancer cells to TAM through suppressing mitogen-activated protein kinase (MAPK) signaling pathway. We found that ERK and P38 were relatively activated in MCF-7/TAM compared with MCF-7, and treatment with MAPK-specific inhibitors can significantly suppress cell viability. Knockdown of KLF4 activated ERK and P38 and drove MCF-7 cells to become resistant to TAM. Conversely, overexpression of KLF4 in MCF-7/TAM cells suppressed ERK and P38 signaling and resulted in enhanced sensitivity to TAM. Therefore, our findings suggest that KLF4 contributes to TAM efficiency in breast cancer via phosphorylation modification of ERK and P38 signaling. Collectively, this study highlighted the significance of KLF4/MAPK signal interaction in regulating TAM resistance of breast cancer, and suggested that targeting the KLF4/MAPK signaling may be a potential therapeutic strategy for breast cancer treatment, especially for TAM-resistant patients. Note: This abstract was not presented at the conference. Citation Format: Yunlu Jia, Wang Linbo. KLF4 overcomes tamoxifen resistance by suppressing MAPK signaling pathway in breast cancer [abstract]. In: Proceedings of the AACR Special Conference: Advances in Breast Cancer Research; 2017 Oct 7-10; Hollywood, CA. Philadelphia (PA): AACR; Mol Cancer Res 2018;16(8_Suppl):Abstract nr A46.