Adiponectin is an adipocyte-secreted adipokine with pleiotropic actions. Clinical evidence has shown that serum adiponectin levels are increased and that adiponectin can protect pancreatic beta cells against apoptosis, which suggests that adiponectin may play an anti-apoptotic role in pancreatic cancer (PC). Here, we investigated the effects of adiponectin on PC development and elucidated the underlying molecular mechanisms. Adiponectin deficiency markedly attenuated pancreatic tumorigenesis in vivo. We found that adiponectin significantly inhibited the apoptosis of both human and mouse pancreatic cancer cells via adipoR1, but not adipoR2. Furthermore, adiponectin can increase AMP-activated protein kinase (AMPK) phosphorylation and NAD-dependent deacetylase sirtuin-1 (Sirt1) of PC cells. Knockdown of AMPK or Sirt1 can increase the apoptosis in PC cells. AMPK up-regulated Sirt1, and Sirt1 can inversely phosphorylate AMPK. Further studies have shown that Sirt1 can deacetylate peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α), which can increase the expression levels of mitochondrial genes. Thus, adiponectin exerts potent anti-apoptotic effects on PC cells via the activation of AMPK/Sirt1/PGC1α signaling. Finally, adiponectin can elevate β-catenin levels. Taken together, these novel findings reveal an unconventional role of adiponectin in promoting pancreatic cancers, and suggest that the effects of adiponectin on tumorigenesis are highly tissue-dependent.

Increasing amounts of evidence has demonstrated that T2DM (Type 2 Diabetes Mellitus) patients have increased susceptibility to CRC (colorectal cancer). As HHEX is a recognized susceptibility gene in T2DM, this work was focused on two SNPs in HHEX, rs1111875 and rs7923837, to study their association with CRC. T2DM patients without CRC (T2DM-only, n=300), T2DM with CRC (T2DM/CRC, n=135), cancer-free controls (Control, n=570), and CRC without T2DM (CRC-only, n=642) cases were enrolled. DNA samples were extracted from the peripheral blood leukocytes of the patients and sequenced by direct sequencing. The χ2 test was used to compare categorical data. We found that in T2DM patients, rs1111875 but not the rs7923837 in HHEX gene was associated with the occurrence of CRC (p= 0.006). for rs1111875, TC/CC patients had an increased risk of CRC (p=0.019, OR=1.592, 95%CI=1.046-2.423). Moreover, our results also indicated that the two variants of HEEX gene could be risk factors for CRC in general population, independent on T2DM (p< 0.001 for rs1111875, p=0.001 for rs7923837). For rs1111875, increased risk of CRC was observed in TC or TC/CC than CC individuals (p<0.001, OR= 1.780, 95%CI= 1.385-2.287; p<0.001, OR= 1.695, 95%CI= 1.335-2.152). For rs7923837, increased CRC risk was observed in AG, GG, and AG/GG than AA individuals (p< 0.001, OR= 1.520, 95%CI= 1.200-1.924; p=0.036, OR= 1.739, 95%CI= 0.989-3.058; p< 0.001, OR= 1.540, 95%CI= 1.225-1.936). This finding highlights the potentially functional alteration with HHEX rs1111875 and rs7923837 polymorphisms may increase CRC susceptibility. Risk effects and the functional impact of these polymorphisms need further validation.

Krüppel-like factor 4 (KLF4) is a zinc-finger transcription factor that regulates many essential processes, including development and cell differentiation, proliferation, and apoptosis. Along with these roles in normal cells and tissues, KLF4 has important tumor suppressive and oncogenic functions in some malignancies. However, the roles of KLF4 in oral squamous cell carcinoma remain unclear. This study investigated the epigenetic alterations and possible roles of KLF4 in oral cancer carcinogenesis. Notably, KLF4 expression was significantly decreased in human oral cancer tissues compared with healthy controls, and KLF4 promoter hypermethylation contributed to the suppression of KLF4 expression. KLF4 expression was associated with tumor grade. Its expression was much lower in poorly differentiated oral cancers than in well-differentiated cancer cells. KLF4 exerted its antitumor activity in vitro and/or in vivo by inhibiting cell proliferation, cell cycle progression, cell colony formation and by inducing apoptosis. In addition, KLF4 over-expression promoted oral cancer cell migration and invasion in vitro. Knockdown of KLF4 promoted oral cancer cells growth and colony formation, and simultaneously inhibited cell migration and invasion. Mechanistic studies revealed that MMP-9 might contribute to KLF4-mediated cell migration and invasion. These results provide evidence that KLF4 might play Janus-faced roles in oral cancer carcinogenesis, acting both as a tumor suppressor and as an oncogene.

RANK/RANKL plays a key role in metastasis of certain malignant tumors, which makes it a promising target for developing novel therapeutic strategies for cancer. However, the prognostic value and pro-metastatic activity of RANK in endometrial cancer (EC) remain to be determined. Thus, the present study investigated the effect of RANK on the prognosis of EC patients, as well as the pro-metastatic activity of EC cells. The results indicated that those with high expression of RANK showed decreased overall survival and progression-free survival. Statistical analysis revealed the positive correlations between RANK/RANKL expression and metastasis-related factors. Additionally, RANK/RANKL significantly promoted cell migration/invasion via activating AKT/β-catenin/Snail pathway in vitro. However, RANK/RANKL-induced AKT activation could be suppressed after osteoprotegerin (OPG) treatment. Furthermore, the combination of medroxyprogesterone acetate (MPA) and RANKL could in turn attenuate the effect of RANKL alone. Similarly, MPA could partially inhibit the RANK-induced metastasis in an orthotopic mouse model via suppressing AKT/β-catenin/Snail pathway. Therefore, therapeutic inhibition of MPA in RANK/RANKL-induced metastasis was mediated by AKT/β-catenin/Snail pathway both in vitro and in vivo, suggesting a potential target of RANK for gene-based therapy for EC.

Accumulating evidence links colorectal cancer (CRC) with the intestinal microbiota. However, the disturbance of intestinal microbiota and the role of Fusobacterium nucleatum during the colorectal adenoma-carcinoma sequence have not yet been evaluated.

Oxidative stress is known to play an important role in oral cancer development. In this study we aimed to examine whether a chemical activator of NRF2, sulforaphane (SFN), may have chemopreventive effects on oxidative stress-associated oral carcinogenesis. We first showed that Nrf2 activation and oxidative damage were commonly seen in human samples of oral leukoplakia. With gene microarray and immunostaining, we found 4-nitroquinoline 1-oxide (4NQO) in drink activated the Nrf2 pathway and produced oxidative damage in mouse tongue. Meanwhile whole exome sequencing of mouse tongue identified mutations consistent with 4NQO's mutagenic profile. Using cultured human oral keratinocytes and 4NQO-treated mouse tongue, we found that SFN pre-treatment activated the NRF2 pathway and inhibited oxidative damage both in vitro and in vivo. On the contrary, a structural analogue of SFN without the isothiocyanate moiety did not have such effects. In a long-term chemoprevention study using wild-type and Nrf2-/- mice, we showed that topical application of SFN activated the NRF2 pathway, inhibited oxidative damage, and prevented 4NQO-induced oral carcinogenesis in an Nrf2-dependent manner. Our data clearly demonstrate that SFN has chemopreventive effects on oxidative stress-associated oral carcinogenesis, and such effects depend on Nrf2 and the isothiocyanate moiety.

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide, and it remains a challenge to understand the genetic mechanisms underlying hepatocarcinogenesis. A global gene network of differential expression profiles in HCC has yet to be fully characterized. In the present study, we performed transcriptome sequencing (mRNA and lncRNA) in liver cancer and cirrhotic tissues of nine HCC patients. We identified differentially expressed genes (DEGs) and constructed a weighted gene co-expression network for the DEGs. In total, 755 DEGs (747 mRNA and eight lncRNA) were identified, and several co-expression modules were significantly associated with HCC clinical traits, including tumor location, tumor grade, and the α-fetoprotein (AFP) level. Of note, we identified 15 hub genes in the module associated with AFP level, and three (SPX, AFP and ADGRE1) of four hub genes were validated in an independent HCC cohort (n=78). Identification of hub genes for HCC clinical traits has implications for further understanding of the molecular genetic basis of HCC.

Binding of leukemia cells to the bone marrow extracellular matrix (ECM) through integrins might influence drug response and the survival of acute myeloid leukemia (AML). However, the functions of integrin in AML are needed to be clarified. Data from The Cancer Genome Atlas (TCGA) were retrieved and integrin β3 (ITGB3) expression and prognostic significance for AML were analyzed. Integrin alphavbeta3 (αvβ3) in sorafenib sensitivity and signaling pathway of FLT3-ITD AML cells was evaluated in vitro. The level of ITGB3 expression was positively correlated with risk stratification and prognosis of AML patients, especially in cytogenetic-normal patients with Fms-like tyrosine kinase-3 internal tandem duplication (FLT3-ITD) mutation. Integrin αvβ3 decreased sorafenib sensitivity when co-culture of MV4-11 cells and bone marrow stromal cells (BMSCs), and it is crucial for osteopontin (OPN) induced sorafenib insensitivity in FLT3-ITD mutated AML cells. Mechanically, αvβ3 enhance β-catenin activation through phosphatidylinositol 3-kinase (PI3K)/Akt/Glycogen synthase kinase-3 beta (GSK3β) pathway. Moreover, genetic inhibition of β-catenin by shRNA could increase sorafenib sensitivity in MV4-11 cells. Taken together, our study revealed a novel mechanism in microenvironment influence on sorafenib sensitivity in AML with FLT3-ITD mutation that was caused by activating integrin αvβ3/PI3K/Akt/GSK3β/β-catenin pathway. Integrin αvβ3/β-catenin could be considered as a new therapeutic target for AML especially for FLT3-ITD mutated AML.

Osteoporosis is a common human complex disease. It is mainly characterized by low bone mineral density (BMD) and low-trauma osteoporotic fractures (OF). Until now, a large proportion of heritability has yet to be explained. The existing large-scale genome-wide association studies (GWAS) provide strong support for the investigation of osteoporosis mechanisms using pathway analysis. Recent findings showed that different risk pathways may be involved in BMD in different tissues. Here, we conducted multiple pathway analyses of a large-scale lumbar spine BMD GWAS dataset (2,468,080 SNPs and 31,800 samples) using two published gene-based analysis software including ProxyGeneLD and the PLINK. Using BMD genes from ProxyGeneLD, we identified 51 significant KEGG pathways with adjusted P<0.01. Using BMD genes from PLINK, we identified 38 significant KEGG pathways with adjusted P<0.01. Interestingly, 33 pathways are shared in both methods. In summary, we not only identified the known risk pathway such as Wnt signaling, in which the top GWAS variants are significantly enriched, but also highlight some new risk pathways. Interestingly, evidence from further supports the involvement of these pathways in MBD.

Anaplastic thyroid carcinoma (ATC) is one of the most lethal carcinoma with a poor prognosis; however, molecular mechanisms underlying the aggressiveness of ATC remain unclear. Our goal was to examine the expression of X-linked inhibitor of apoptosis protein (XIAP) in ATC, as well as its role in ATC tumorigenesis. This is a retrospective study of ATC patients from the Second Affiliated Hospital of Harbin Medical University during June 2003 to October 2013. The expression of XIAP in tumor specimens of ATC patients was examined by immunohistochemical staining. The roles of XIAP in proliferation, migration, invasion, and chemoresistance were investigated by shRNA mediated-knockdown of XIAP in human ATC cell lines. The effect of XIAP on tumorigenesis was evaluated using a xenograft tumor model with nude mice. XIAP expression was significantly higher in the invasive area of ATC samples, whereas XIAP expression was negative in either normal thyroid follicular epithelial cells or the differentiated papillary thyroid carcinoma. XIAP-depleted ATC cells showed a remarkable decrease in the proliferation, migration, and invasion compared with the scramble group. Knockdown of XIAP expression significantly enhanced the chemosensitivity of WRO and SW1736 cells to docetaxel or taxane. Moreover, knockdown of XIAP significantly suppressed ATC tumorigenesis in vivo. XIAP is highly expressed in ATC cells and tumors. XIAP play important roles in tumor behaviors and chemosensitivity of ATC cells. XIAP may function in ATC aggressiveness and may serve as a potential therapeutic target for ATC treatment.

Acute myeloid leukemia (AML) is a heterogeneous disorder of the hematopoietic system with no common genetic "Achilles heel" that can be targeted. Most patients respond well to standard therapy, while a majority relapse, and development of an effective therapy for AML patients is still urgently needed. In this study, we demonstrated that betulinic acid (BA) significantly increased Aryl hydrocarbon receptor (AHR) expression through demethylation on the AHR promoter in AML cells, and the increased AHR expression interacts with and sequesters ARNT, subsequently suppressing hypoxia-inducible factor-1α (HIF1α) pathway. We also found that histone deacetylase inhibitor chidamide (CDM) treatment significantly increased p300 over-acetylation in AML cells with dissociation of p300 with HIF1α, and subsequently suppressed the HIF1α pathway. Further investigation showed that BA/CDM combination additively increased generation of reactive oxygen species (ROS) with DNA damage, apoptosis and mitochondrial dysfunction. Also, BA/CDM combination additively suppressed the HIF1α pathway with decreased VEGF expression. in vivo mice study showed that BA/CDM combination significantly suppressed AML tumor growth, and overexpression of SOD2 and a constitutive HIF1α (HIF1C) completely diminished this effect. We conclude that a BA/CDM combination inhibits AML tumors through ROS over-generation and HIF1α pathway suppression. This is the first time we have shown the potential effect and possible mechanism of BA and CDM on the inhibition of AML tumor growth.

Hepatocellular carcinoma (HCC) is one of the most malignant cancers. Conventional therapies are limited due to the human liver being such a unique organ and easily showing side-effects. The unclear molecular mechanisms are tough challenges for scientists searching for new and effective anti-HCC targeting drugs. We identified that the nuclear receptor NR4A2 is a novel oncogene in HCC progression. In this study, we show that NR4A2 and the notch recceptor Notch1 were expressed highly in primary HCC tissues and immortal HCC cells by using qPCR, western blot and immuno-histochemistry assays. Both genes were observed to stimulate HCC cell proliferation, anti-apoptosis and cell cycle arrest by using cell proliferation assays and FACS assays. We also observed that the four notch receptor subtypes (Notch1-4) displayed different effects on HCC cell growth. The over-expression of Notch1 by transiently transfecting the intracellular domain of Notch1 (ICN1, Notch1 active form) increased the expression of NR4A2, with the knockdown of Notch1 decreasing NR4A2. This indicates that NR4A2 is one of the Notch-mediated downstream genes. Moreover, both NR4A2 and Notch1 suppressed the expression of tumor suppressors p21 and p63. These findings support that Notch1/NR4A2 co-regulate HCC cell functions by playing oncogenic roles and regulating the associated downstream signaling pathways. Novel Notch1/NR4A2-mediated oncogenic signaling may provide us a great opportunity for anti-HCC drug development.

Despite the development of many anticancer agents over the past 20 years, ovarian cancer remains the most lethal gynecologic malignancy. Due to a lack of effective screening, the majority of patients with ovarian cancer are diagnosed at an advanced stage, and only ~20% of patients are cured. Thus, in addition to improved screening methods, there is an urgent need for novel anticancer agents that are effective against late-stage, metastatic disease. Oncolytic virotherapy is a promising approach; unfortunately, systemic delivery of viruses to tumors remains a major challenge. In this regard, neural stem/progenitor cells (NSCs) with well-established tumor-homing properties may serve as an effective delivery platform for oncolytic viruses. In this study, we tested the efficacy of myxoma virus (MYXV), a rabbit-specific poxvirus that has demonstrated efficacy against a variety of tumors, using human and mouse ovarian cancer cell lines. We showed that MYXV effectively lysed ovarian cancer cells in vitro, reducing their viability. We also demonstrated that MYXV can infect human NSCs, specifically the clonal HB1.F3.CD21 NSC line. Taken together, these results suggest that NSC-mediated delivery of MYXV may be a promising strategy for achieving more selectively targeted anti-tumor efficacy.

Excessive nutrition promotes the pathogenesis of non-alcoholic steatohepatitis (NASH), characterized by the accumulation of pro-inflammation mediators in the liver. In the present study we investigated the regulation of pro-inflammatory transcription in hepatocytes by protein inhibitor of activated STAT 4 (PIAS4) in this process and the underlying mechanisms. We report that expression of the class III deacetylase SIRT1 was down-regulated in the livers of NASH mice accompanied by a simultaneous increase in the expression and binding activity of PIAS4. Exposure to high glucose stimulated the expression PIAS4 in cultured hepatocytes paralleling SIRT1 repression. Estrogen, a known NASH-protective hormone, ameliorated SIRT1 trans-repression by targeting PIAS4. Over-expression of PIAS4 enhanced, while PIAS4 knockdown alleviated, repression of SIRT1 transcription by high glucose. Lentiviral delivery of short hairpin RNA (shRNA) targeting PIAS4 attenuated hepatic inflammation in NASH mice by restoring SIRT1 expression. Mechanistically, PIAS4 promoted NF-κB-mediated pro-inflammatory transcription in a SIRT1 dependent manner. In conclusion, our study indicates that PIAS4 mediated SIRT1 repression in response to nutrient surplus contributes to the pathogenesis of NASH. Therefore, targeting PIAS4 might provide novel therapeutic strategies in the intervention of NASH.

Pancreatic ductal adenocarcinoma (PDAC), which accounts for 96% of all pancreatic cancer cases, is characterized by rapid progression, invasion and metastasis. Transforming growth factor-beta (TGF-β) signaling is an essential pathway in metastatic progression and microRNAs (miRNA) play central roles in the regulation of various biological and pathologic processes including cancer metastasis. However, the molecular mechanisms involved in regulation of miRNAs and activation of TGF-β signaling in PDAC remain to be established. The results of this study suggested that miR-323-3p expression in PDAC tissues and cell lines was significantly decreased compared to levels in normal pancreatic tissues and primary cultured pancreatic duct epithelial cells. Further investigation revealed that miR-323-3p directly targeted and suppressed SMAD2 and SMAD3, both key components in TGF-β signaling. Lower levels of miR-323-3p predicted poorer prognosis in patients with PDAC. Ectopic overexpression of miR-323-3p significantly inhibited, while silencing of miR-323-3p increased the migration and invasion abilities of PDAC cells in vitro. Moreover, using an in vivo mouse model, we demonstrated that overexpressing of miR-323-3p significantly reduced, while knockdown of miR-323-3p enhanced lung metastatic colonization of PANC-1 cells. Furthermore, miR-323-3p-induced TGF-b signaling inhibition and cell motility suppression were partially rescued by overexpressing of Smad2 and Smad3 in PDAC cells. Our findings suggest that re-expression of miR-323-3p might offer a novel therapeutic target against metastasis in patients with PDAC.

EZH2 is a negative prognostic factor and is overexpressed or activated in most human cancers including head and neck squamous cell carcinoma (HNSCC). Analysis of The Cancer Genome Atlas (TCGA) HNSCC data indicated that EZH2 over-expression was associated with high tumor grade and conferred poor prognosis. EZH2 inhibition triggered cell apoptosis, cell cycle arrest and decreased cell growth in vitro. MICU1 (mitochondrial calcium uptake1) was shown to be down regulated when EZH2 expression was inhibited in HNSCC. When the EZH2 and MICU1 were inhibited, HNSCC cells became susceptible to cell cycle arrest and apoptosis. Mitochondrial membrane potential and cytosolic Ca2+ concentration analysis suggested that EZH2 and MICU1 were required to maintain mitochondrial membrane potential stability. A xenograft tumor model was used to confirm that EZH2 depletion inhibited HNSCC cell growth and induced tumor cell apoptosis. In summary, EZH2 is a potential anti-tumor target in HNSCC.

Head and neck squamous cell carcinoma (HNSCC) is the fifth most common cancer worldwide and a common cause of cancer-related death, with a 5-year survival rate of less than 60%. IL-6 has been suggested to play an important role in cancer metastasis, but its mechanism in HNSCC has not been fully clarified. p70S6K has been reported to induce epithelial-mesenchymal transition (EMT) of ovarian cancer, but its role in HNSCC remains unknown. In this study, we found that p70S6K and IL-6 were upregulated in high-metastatic HNSCC cell lines that underwent EMT when compared to paired low-metastatic cell lines. Overexpression of p70S6K promoted EMT and migration of HNSCC cells, while downregulation of p70S6K attenuated IL-6-induced EMT and cell migration. Furthermore, IL-6-induced p70S6K activation was attenuated by inhibitors of the PI3K/Akt/mTOR, MAPK/ERK, and JAK/STAT3 signaling pathways, suggesting that it located downstream of these pathways. These findings suggest that p70S6K promotes IL-6-induced EMT and metastasis of HNSCC. Targeting p70S6K for HNSCC therapy may benefit patients through the inhibition of tumor growth, as well as metastasis.

Adipose-derived stem cells (ADSCs) are multipotent cells that have attracted much recent attention. Here, we show that ADSCs enhance sphere formation and in vivo tumor initiation of breast and colon cancer cells. In co-culture, ADSCs induced several stem cell markers in cancer cells. ADSCs also accelerated tumor growth. Interaction of ADSCs and cancer cells stimulated secretion of interlukin-6 in ADSCs, which in turn acted in a paracrine manner on cancer cells to enhance their malignant properties. Interleukin-6 regulated stem cell-related genes and activated JAK2/STAT3 in cancer cells. We suggest that ADSCs may enhance tumor initiation and promotion.

Emerging evidence indicates that microRNAs, a class of small and well-conserved noncoding RNAs, participate in many physiological and pathological processes. RNase III endonuclease DICER is one of the key enzymes for microRNA biogenesis. Here, we found that DICER was downregulated in tumor samples of colorectal cancer (CRC) patients at both mRNA and protein levels. Importantly, intestinal epithelial cell (IEC)-specific deletion of Dicer mice got more tumors after azoxymethane and dextran sulfate sodium (DSS) administration. Interestingly, IEC-specific deletion of Dicer led to severe chronic inflammation and epithelium layer remodeling in mice with or without DSS administration. Microarray analysis of 3 paired Dicer deletion CRC cell lines showed that miR-324-5p was one of the most significantly decreased miRNAs. In the intestinal epithelium of IEC-specific deletion of Dicer mice, miR-324-5p was also found to be markedly reduced. Mechanistically, miR-324-5p directly bound to the 3'untranslated regions (3'UTRs) of HMG-box containing 3 (HMGXB3) and WAS protein family member 2 (WASF-2), two key proteins participated in cell motility and cytoskeleton remodeling, to suppress their expressions. Intraperitoneal injection of miR-324-5p AgomiR (an agonist of miR-324-5p) curtailed chronic inflammation and cytoskeleton remodeling of colorectal epithelium and restored intestinal barrier function in IEC-specific deletion of Dicer mice induced by DSS. Therefore, our study reveals a key role of a DICER/miR-324-5p/HMGXB3/WASF-2 axis in tumorigenesis of CRC by regulation of cytoskeleton remodeling and maintaining integrity of intestinal barriers.

Dectin-1 is the critical sensor for β-glucan from Candida which is the most common human fungal pathogen and cause superficial and system infection. MicroRNAs (miRNAs) play crucial roles in regulating innate immunity. However, the functional role of miRNAs in inflammatory response dependent on the activation of dectin-1 pathway has not been defined. In the present study, we found insoluble β-glucan from the cell wall of Candida albicans (CaIG) was able to increase the production of of IL-6 and TNFα through Dectin-1-Syk-NF-κB and p38MAPK pathway. MiRNAs profiles combined with real-time PCR validation revealed that miR-146a, miR-30-5p, miR-210-3p expression level were increased in THP-1 cells treated with CaIG. The interaction between Dectin-1 and CaIG resulted in an long lasting increase of miR-146a expression dependent on Dectin-1-Syk-NF-κB, p38MAPK, contrasting with a rapid and transient increase of IL-6 and TNFα. Overexpression of miR-146a significantly suppressed the production of IL-6 and TNFα. MiR-146a mimics inhibited CaIG-induced activity of p-IκBα and translocation of NF-κB p65. Luciferase reporter assays showed miR-146a inhibited NF-κB promoter-binding activity. Together, our data suggest miR-146a may play the potent negative feedback regulator in inflammatory response following Dectin-1 stimulation.