Platelet-derived extracellular vesicles encapsulate microRNA-34c-5p to ameliorate inflammatory response of coronary artery endothelial cells via PODXL-mediated P38 MAPK signaling pathway.

BACKGROUND AND AIMS: Low-grade chronic inflammation was reported to serve as a distinctive pathophysiologic feature of coronary artery disease (CAD), the leading cause of death around the world. Herein, the current study aimed to explore whether and how microRNA-34c-5p (miR-34c-5p), a miRNA enriched in extracellular vesicles (EVs) originated from the activated platelet (PLT-EVs), affects the inflammation of human coronary artery endothelial cells (HCAECs). METHODS AND RESULTS: HCAECs were established as an in vitro cell model using oxidized low-density lipoprotein (ox-LDL). miR-34c-5p, an abundant miRNA in PLT-EVs, can be transferred to HCAECs and target PODXL by binding to its 3'UTR. Gain- and loss-of-function experiments of miR-34c-5p and podocalyxin (PODXL) were performed in ox-LDL-induced HCAECs. Subsequently, HCAECs were subjected to co-culture with PLT-EVs, followed by detection of the expression patterns of key pro-inflammatory factors. Either miR-34c-5p mimic or PLT-EVs harboring miR-34c-5p attenuated the ox-LDL-evoked inflammation in HCAECs by suppressing interleukin-1ß (IL-1ß), IL-6 and tumor necrosis factor-α (TNF-α). By blocking the P38 MAPK signaling pathway, miR-34c-5p-mediated depletion of PODXL contributed to protection against ox-LDL-induced inflammation. In vitro findings were further validated by findings observed in ApoE knock-out mice. Additionally, miR-34c-5p in PLT-EVs showed an athero-protective role in the murine model. CONCLUSION: Altogether, our findings highlighted that miR-34c-5p in PLT-EVs could alleviate inflammation response in HCAECs by targeting PODXL and inactivation of the P38 MAPK signaling pathway.

Germinal epimutation of Fragile Histidine Triad (FHIT) gene is associated with progression to acute and chronic adult T-cell leukemia diseases.

BACKGROUND: Human T cell Leukemia virus type 1 (HTLV-I) is etiologically linked to adult T cell leukemia/lymphoma (ATL) and an inflammatory neurodegenerative disease called HTLV-I-associated myelopathy or tropical spastic paraparesis (HAM/TSP). The exact genetic or epigenetic events and/or environmental factors that influence the development of ATL, or HAM/TSP diseases are largely unknown. The tumor suppressor gene, Fragile Histidine Triad Diadenosine Triphosphatase (FHIT), is frequently lost in cancer through epigenetic modifications and/or deletion. FHIT is a tumor suppressor acting as genome caretaker by regulating cellular DNA repair. Indeed, FHIT loss leads to replicative stress and accumulation of double DNA strand breaks. Therefore, loss of FHIT expression plays a key role in cellular transformation. METHODS: Here, we studied over 400 samples from HTLV-I-infected individuals with ATL, TSP/HAM, or asymptomatic carriers (AC) for FHIT loss and expression. We examined the epigenetic status of FHIT through methylation specific PCR and bisulfite sequencing; and correlated these results to FHIT expression in patient samples. RESULTS: We found that epigenetic alteration of FHIT is specifically found in chronic and acute ATL but is absent in asymptomatic HTLV-I carriers and TSP/HAM patients' samples. Furthermore, the extent of FHIT methylation in ATL patients was quantitatively comparable in virus-infected and virus non-infected cells. We also found that longitudinal HTLV-I carriers that progressed to smoldering ATL and descendants of ATL patients harbor FHIT methylation. CONCLUSIONS: These results suggest that germinal epigenetic mutation of FHIT represents a preexisting mark predisposing to the development of ATL diseases. These findings have important clinical implications as patients with acute ATL are rarely cured. Our study suggests an alternative strategy to the current "wait and see approach" in that early screening of HTLV-I-infected individuals for germinal epimutation of FHIT and early treatment may offer significant clinical benefits.

ALDH1A1 promotes PARP inhibitor resistance by enhancing retinoic acid receptor-mediated DNA polymerase θ expression.

Poly (ADP-ribose) Polymerase (PARP) inhibitors (PARPi) have been approved for both frontline and recurrent setting in ovarian cancer with homologous recombination (HR) repair deficiency. However, more than 40% of BRCA1/2-mutated ovarian cancer lack the initial response to PARPi treatment, and the majority of those that initially respond eventually develop resistance. Our previous study has demonstrated that increased expression of aldehyde dehydrogenase 1A1 (ALDH1A1) contributes to PARPi resistance in BRCA2-mutated ovarian cancer cells by enhancing microhomology-mediated end joining (MMEJ) but the mechanism remains unknown. Here, we find that ALDH1A1 enhances the expression of DNA polymerase θ (Polθ, encoded by the POLQ gene) in ovarian cancer cells. Furthermore, we demonstrate that the retinoic acid (RA) pathway is involved in the transcription activation of the POLQ gene. The RA receptor (RAR) can bind to the retinoic acid response element (RARE) located in the promoter of the POLQ gene, promoting transcription activation-related histone modification in the presence of RA. Given that ALDH1A1 catalyzes the biosynthesis of RA, we conclude that ALDH1A1 promotes POLQ expression via the activation of the RA signaling pathway. Finally, using a clinically-relevant patient-derived organoid (PDO) model, we find that ALDH1A1 inhibition by the pharmacological inhibitor NCT-505 in combination with the PARP inhibitor olaparib synergistically reduce the cell viability of PDOs carrying BRCA1/2 mutation and positive ALDH1A1 expression. In summary, our study elucidates a new mechanism contributing to PARPi resistance in HR-deficient ovarian cancer and shows the therapeutic potential of combining PARPi and ALDH1A1 inhibition in treating these patients.

Gut Microbiome and Metabolomics Profiles of Allergic and Non-Allergic Childhood Asthma.

Purpose: This study aimed to investigate the characteristics of gut bacteria and the derived metabolites among allergic asthmatic children, non-allergic asthmatic children and healthy children without asthma. Methods: Fecal samples were collected from 57 participants, including 20 healthy children, 27 allergic asthmatic children, and 10 non-allergic asthmatic children. 16S rRNA gene sequencing was conducted for analyzing gut bacterial compositions and untargeted metabolomics was used to analyze the alterations of gut microbe-derived metabolites. The associations between gut bacterial compositions and metabolites were analyzed by the method of Spearman correlation. Results: The results showed that the compositions and metabolites of gut microbiome were altered both in allergic and non-allergic asthmatics compared with healthy controls. Chao1 (p = 0.025) index reflected a higher bacterial richness and Simpson (p = 0.024) index showed a lower diversity in asthma group. PERMANOVA analysis showed significant differences among the three groups based on unweighted UniFrac distance (p = 0.001). Both allergic and non-allergic asthmatics showed a higher relative abundance of Proteobacteria and a lower relative abundance of genera from Clostridia. More bacteria were altered in non-allergic asthmatics compared with allergic asthmatics. Metabolomics analysis identified that 42 metabolites were significantly associated with allergic asthma, and 58 metabolites were significantly associated with non-allergic asthma (multiple linear regression, p < 0.05). Histamine was 4 folds up-regulated only in the non-allergic asthma group. The relative abundance of Candidatus Accumulib was significantly correlated with the upregulation of histamine. The relative abundance of genera from Clostridia was significantly correlated with the downregulation of lipid and tryptophan metabolism. Conclusion: The altered gut microbes was associated with the mechanism of asthma attack through metabolites in allergic and non-allergic asthma group, respectively. The result suggested that gut microbiome had an impact on the development of both allergic and non-allergic asthma. The distinct gut microbiome and microbiome-derived metabolites in non-allergic asthma children suggested that gut microbiome might play a critical role in modulation of asthma phenotype.

ERK inactivation enhances stemness of NSCLC cells via promoting Slug-mediated epithelial-to-mesenchymal transition.

Rationale: The mitogen-activated protein kinase pathway (MAPK) is one of the major cancer-driving pathways found in non-small cell lung cancer (NSCLC) patients. ERK inhibitors (ERKi) have been shown to be effective in NSCLC patients with MAPK pathway mutations. However, like other MAPK inhibitors, ERKi rarely confers complete and durable responses. The mechanism of tumor relapse after ERKi treatment is yet defined. Methods: To best study the mechanism of tumor relapse after ERK inhibitor treatment in NSCLC patients, we treated various NSCLC cell lines and patient-derived xenograft (PDX) with ERK inhibitors and evaluated the enrichment of cancer stem cell (CSC) population. We then performed a Next-generation sequencing (NGS) to identify potential pathways that are responsible for the CSC enrichment. Further, the involvement of specific pathways was examined using molecular and cellular methods. Finally, we investigated the therapeutic benefits of ERKi treatment combined with JAK/STAT pathway inhibitor using cellular and xenograft NSCLC models. Results: We found that ERKi treatment expands the CSC population in NSCLC cells through enhanced epithelial-to-mesenchymal transition (EMT)-mediated cancer cell dedifferentiation. Mechanistically, ERK inactivation induces EMT via pSTAT3-mediated upregulation of Slug, in which, upregulation of miR-204 and downregulation of SPDEF, a transcription repressor of Slug, are involved. Finally, the JAK/STAT pathway inhibitor Ruxolitinib blocks the ERK inactivation-induced EMT and CSC expansion, as well as the tumor progression in xenograft models after ERKi treatment. Conclusions: This study revealed a potential tumor relapse mechanism of NSCLC after ERK inhibition through the unintended activation of the EMT program, ascertained the pSTAT-miR-204-SPDEF-Slug axis, and provided a promising combination inhibitor approach to prevent tumor relapse in patients.

A Novel Estrogen Receptor ß Agonist Diminishes Ovarian Cancer Stem Cells via Suppressing the Epithelial-to-Mesenchymal Transition.

Epithelial ovarian cancer is the most lethal malignancy of the female reproductive tract. A healthy ovary expresses both Estrogen Receptor α (ERα) and ß (ERß). Given that ERα is generally considered to promote cell survival and proliferation, thereby, enhancing tumor growth, while ERß shows a protective effect against the development and progression of tumors, the activation of ERß by its agonists could be therapeutically beneficial for ovarian cancer. Here, we demonstrate that the activation of ERß using a newly developed ERß agonist, OSU-ERb-12, can impede ovarian cancer cell expansion and tumor growth in an ERα-independent manner. More interestingly, we found that OSU-ERb-12 also reduces the cancer stem cell (CSC) population in ovarian cancer by compromising non-CSC-to-CSC conversion. Mechanistically, we revealed that OSU-ERb-12 decreased the expression of Snail, a master regulator of the epithelial-to-mesenchymal transition (EMT), which is associated with de novo CSC generation. Given that ERα can mediate EMT and facilitate maintenance of the CSC subpopulation and that OSU-ERb-12 can block the transactivity of ERα, we conclude that OSU-ERb-12 reduces the CSC subpopulation by inhibiting EMT in an ERα-dependent manner. Taken together, our data indicate that the ERß agonist OSU-ERb-12 could be used to hinder tumor progression and limit the CSC subpopulation with the potential to prevent tumor relapse and metastasis in patients with ovarian cancer.

Platelet-derived growth factor-mediated induction of the synaptic plasticity gene Arc/Arg3.1.

Platelet-derived growth factor (PDGF) is a pleiotropic protein with critical roles in both developmental as well as pathogenic processes. In the central nervous system specifically, PDGF is critical for neuronal proliferation and differentiation and has also been implicated as a neuroprotective agent. Whether PDGF also plays a role in synaptic plasticity, however, remains poorly understood. In the present study we demonstrated that in the rat hippocampal neurons PDGF regulated the expression of Arc/Arg3.1 gene that has been implicated in both synapse plasticity and long term potentiation. Relevance of these findings was further confirmed in vivo by injecting mice with intracerebral inoculations of PDGF, which resulted in a rapid induction of Arc in the hippocampus of the injected mice. PDGF induced long term potentiation in rat hippocampal slices, which was abolished by PDGF receptor-tyrosine kinase inhibitor STI-571. We also present evidence that PDGF-mediated induction of Arc/Arg3.1 involved activation of the MAPK/ERK (MEK) pathway. Additionally, induction of Arc/Arg3.1 also involved the upstream release of intracellular calcium stores, an effect that could be blocked by thapsigargin but not by EGTA. Pharmacological approach using inhibitors specific for either MAPK/ERK phosphorylation or calcium release demonstrated that the two pathways converged downstream at a common point involving activation of the immediate early gene Egr-1. Chromatin immunoprecipitation assays demonstrated the binding of Egr-1, but not Egr-3, to the Arc promoter. These findings for the first time, thus, suggest an additional role of PDGF, that of induction of Arc.

Protective Effects of Bariatric Surgery on Kidney Functions by Inhibiting Oxidative Stress Responses Through Activating PPARα in Rats With Diabetes.

OBJECTIVE: The aim of this study was to explore the protective effects and the regulatory mechanisms of bariatric surgery on kidney injury in diabetic rats. METHODS: We established a useful type 2 diabetic rat model using high-fat and high-sugar diet feeding following low-dose streptozotocin (STZ) treatment. Sprague-Dawley (SD) rats were randomly divided into the following groups: control (Con) group, diabetic nephropathy (DN) group, and duodenal-jejunal bypass (DJB) surgery group. The food intake and body weight of rats were monitored and the glucose tolerance test (OGTT) test was performed every 2 weeks. The glomerular filtration rate (GFR) and urinary albumin excretion rate (UAFR) were measured to assess renal function. Hematoxylin-eosin (H&E), periodic acid-Schiff (PAS), and Masson staining were used to evaluate renal histopathological changes. TUNEL assay was performed to detect cell apoptosis. The expressions of oxidative stress factors and inflammatory factors in the renal tissues of rats were detected by ELISA. The expressions of PPARα, reactive oxygen species (ROS), and NF-κB were detected by immunofluorescence. For in vitro experiment, HK2 cells cultured with high glucose were treated with PPARα agonist, PPARα antagonist, and adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) agonist. The expressions of AMPK/PPARα/NF-κB signaling pathway-related proteins were detected by Western blot. RESULTS: Bariatric surgery improved the glucose tolerance of DN rats. The GFR was decreased, the promotion of urinary albumin excretion rate (UAER) was inhibited, and the renal injury was alleviated. The extracellular matrix fraction was decreased and the renal function was improved. Meanwhile, bariatric surgery activates PPARα, inhibits ROS release, reduces oxidative stress injury, and reduces renal cell apoptosis. In vitro experiment results showed that the AMPK activator could activate PPARα, downregulate NF-κB, and inhibit inflammatory response. The phosphorylation of AMPK was inhibited by PPARα antagonism. CONCLUSION: Bariatric surgery can activate PPARα, inhibit oxidative stress injury, and improve glucose metabolism and renal function in DN rats.

Determination of DNA lesion bypass using a ChIP-based assay.

DNA lesion bypass facilitates DNA synthesis across bulky DNA lesions, playing a critical role in DNA damage tolerance and cell survival after DNA damage. Assessing lesion bypass efficiency in the cell is important to better understanding of the mechanism of carcinogenesis and chemoresistance. Here we developed a chromatin immunoprecipitation (ChIP)-based method to measure lesion bypass activity across cisplatin-induced intrastrand crosslinks in cancer cells. DNA lesion bypass enables the replication to continue in the presence of replication blocks. Thus, the successful lesion bypass should result in the coexistence of DNA lesions and the newly synthesized DNA fragment opposite to this lesion. Using ChIP, we precipitated the cisplatin-induced intrastrand crosslinks, and quantitated the precipitated newly synthesized DNA that was labeled with BrdU. We validated this method on ovarian cancer cells with inhibited TLS activity. We then applied this method to show that ovarian cancer stem cells exhibit high lesion bypass activity relative to bulk cancer cells from the same cell line. In conclusion, this novel ChIP-based lesion bypass assay can detect the extent to which cisplatin-induced DNA lesions are bypassed in live cells. Our study may be applied more broadly to the study of other DNA lesions, as specific antibodies to these specific lesions are available.

HTLV-I p30 inhibits multiple S phase entry checkpoints, decreases cyclin E-CDK2 interactions and delays cell cycle progression.

BACKGROUND: Human T-cell leukemia virus type I (HTLV-I) has efficiently adapted to its host and establishes a persistent infection characterized by low levels of viral gene expression and slow proliferation of HTLV-I infected cells over decades. We have previously found that HTLV-I p30 is a negative regulator of virus expression. RESULTS: In this study we show that p30 targets multiple cell cycle checkpoints resulting in a delayed entry into S phase. We found that p30 binds to cyclin E and CDK2 and prevents the formation of active cyclin E-CDK2 complexes. In turn, this decreases the phosphorylation levels of Rb and prevents the release of E2F and its transcriptional activation of genes required for G1/S transition. Our studies also show that HTLV-II p28 does not bind cyclin E and does not affect cell cycle progression. CONCLUSIONS: In contrast to HTLV-I, the HTLV-II-related retrovirus is not oncogenic in humans. Here we report that the HTLV-I p30 delays cell cycle progression while its homologue, HTLV-II p28, does not, providing evidence for important differences between these two related retrovirus proteins.

In vivo interstitial migration of primitive macrophages mediated by JNK-matrix metalloproteinase 13 signaling in response to acute injury.

Interstitial cell migration through extracellular matrix is a hallmark of the inflammation response, tumor invasion, and metastasis. We have established a stable zebrafish transgenic line expressing enhanced GFP under the lysozyme C promoter for visualizing and measuring primitive macrophage migration in vivo. We show that tissue-resident primitive macrophages migrate rapidly through extracellular matrix to the site of acute injury induced by tail transection. Mechanistically, the specific inhibition of JNK, but not p38 and ERK, dramatically abolished the chemotactic migration in a dose-dependent manner, suppressing the trauma-induced recruitment of phosphorylated C-Jun transcription factor to proximal AP-1 sites in the promoter of matrix metalloproteinase 13 (mmp13), a gene specifically expressed in primitive macrophages during embryogenesis and required for the interstitial migration. Furthermore, dexamethasone suppressed the trauma-induced JNK phosphorylation and macrophage migration accompanied by simultaneous up-regulation of mkp-1, a well-known phosphatase capable of inactivating phosphorylated JNK. The results indicate that the JNK-Mmp13 signaling pathway plays an essential role in regulating the innate immune cell migration in response to severe injury in vivo.

The Impact of Air Pollution on Intestinal Microbiome of Asthmatic Children: A Panel Study.

Air pollution could impact on the alteration of intestinal microbiome. Maturation of intestinal microbiome in early life played an important role in the development of allergic diseases, including asthma. Recent studies presented an increase in the evidence of association between the shift of gut microbiota and asthma. This article is aimed at exploring whether the alteration in the intestinal microbiome triggered by a short wave of air pollution could influence the colonization of bacteria that have been related to the immunological mechanisms of the asthma attack. The impact of air pollution on intestinal microbiome was assessed by longitudinal comparison. Fecal samples were collected twice for twenty-one children in clean and smog days, respectively, including eleven asthmatic children and ten healthy children. Intestinal bacteria were discriminated by using the method of 16S rRNA gene sequence. The results showed that the composition of intestinal microbiome changed between clean and smog days among all children (PERMANOVA, P = 0.03). During smog days, Bifidobacteriaceae, Erysipelotrichaceae, and Clostridium sensu stricto 1 decreased, and Streptococcaceae, Porphyromonadaceae, Rikenellaceae, Bacteroidales S24-7 group, and Bacteroides increased in asthmatic children (Wilcoxon test, P < 0.05), while Fusicatenibacter decreased and Rikenellaceae and Terrisporobacter increased in healthy children (Wilcoxon test, P < 0.05). After controlling for food consumption, the relative abundance of some bacteria belonging to Firmicutes negatively associated with concentration of PM2.5, PM10, NO2, and SO2 (multiple linear regression, P < 0.05). This study demonstrated that short wave of air pollution had an impact on the intestinal microbiome of asthmatic children. Intestinal bacteria, which have been related to immunological mechanisms of asthma attack, were also found to be associated with air pollution. This finding suggested that a short wave of air pollution may trigger asthma by impacting on intestinal bacteria.

[Viable but nonculturable state of bacteria and its hygiene significance].

Viable but nonculturable state of bacteria means the state of bacteria cannot be cultured in routine media, but is alive and metabolic active. Many bacteria including some pathogens can enter this state and maintain virulence or pathogenicity. In this paper, the information including character, induction factors, resuscitation, detection and hygiene significance about bacteria's viable but nonculturable state was reviewed.

[TRPV1 UTR-3 polymorphism and susceptibility of childhood asthma of the Han Nationality in Beijing].

OBJECTIVE: To explore TRPV1 UTR-3 polymorphism and susceptibility of childhood asthma of Han Nationality in Beijing. METHODS: 177 asthmatics, 44 atopy, and 151 control children less than 14-years-old were enrolled in case-control study, and all subjects were investigated by ISSAC questionnaires. Dominant, recessive, co-dominant, over-dominant, and log additive model were used to do genotype analysis, and LD analysis and haplotypes of SNPs were tested by Haploview 4.1. Hardy-Weinberg equilibrium test, Person chis-square test, linkage disequilibrium analysis, and logistic analysis were performed by SAS 9.1 software to determine the association between polymorphisms of TRPV1 and susceptibility of childhood asthma. RESULTS: Polymorphisms were found in rs402369, rs4790521, and rs4790522, Hardy-Weinberg P > 0.05. As to allele frequencies, frequency of SNP rs4790521 T/C in asthmatics were significantly increased (P < 0.05), no significant difference were found in MAF of rs402369 and rs4790522 (P > 0.05). Genotype analysis showed that rs4790521 C/C and rs4790522 A/C were associated with childhood asthma (P < 0.05), and odd ratios were 2.94 (1.32 - 6.53) and 0.588 (0.376 - 0.920) respectively. LD were found between rs4790521 and rs4790522, 3 haplotypes were built. Adjusted by age, gender, parent asthma history, and smoking exposure, logistic stepwise analysis showed that MAF of rs4790521, allozygote C/C of rs4790521, and haplotype C/C were associated with susceptibility to childhood asthma in Chinese Han Nationality in Beijing (P < 0.05). CONCLUSION: TRPV1 UTR-3 polymorphisms could be associated with the susceptibility to childhood asthma of Han Nation a city in Beijing.

Shape-dependent toxicity of alumina nanoparticles in rat astrocytes.

Nanosized alumina (Al2O3-NPs), a widely used nanoparticle in numerous commercial applications, is released into environment posing a threat to the health of wildlife and humans. Recent research has revealed essential roles of physicochemical properties of nanoparticles in determining their toxicity potencies. However, influence of shape on neurotoxicity induced by heterogeneous Al2O3-NPs remains unknown. We herein compared the neurotoxicity of two shapes of γ-Al2O3-NPs (flake versus rod) and their effects on metabolic profiles of astrocytes in rat cerebral cortex. While exposed to both shapes caused significant cytotoxicity and apoptosis in a dose-dependent manner after 72 h exposure, a significantly stronger response was observed for nanorods than for nanoflakes. These effects were associated with significantly greater ROS accumulation and inflammation induction, as indicated by increased concentrations of IL-1ß, IL-2 and IL-6. Using untargeted metabolomics, significant alternations in metabolism of amino acids, lipids and purines, and pyrimidines were observed after exposure to both types. Moreover, changes in the metabolome caused by nanorods were significantly greater than those by nanoflakes as also indicated by physiological stress responses to ROS, inflammation, and apoptosis. Taken together, these findings demonstrated the critical role of morphology in determining toxic potencies of nano-alumina and its underlying mechanisms of toxic actions.

Quantitative structure-property relationships for octanol-water partition coefficients of polybrominated diphenyl ethers.

Theoretical molecular descriptors were tested against logK(OW) values for polybrominated diphenyl ethers (PBDEs) using the Partial Least-Squares Regression method which can be used to analyze data with many variables and few observations. A quantitative structure-property relationship (QSPR) model was successfully developed with a high cross-validated value (Q(cum)(2)) of 0.961, indicating a good predictive ability and stability of the model. The predictive power of the QSPR model was further cross-validated. The values of logK(OW) for PBDEs are mainly governed by molecular surface area, energy of the lowest unoccupied molecular orbital and the net atomic charges on the oxygen atom. All these descriptors have been discussed to interpret the partitioning mechanism of PBDE chemicals. The bulk property of the molecules represented by molecular surface area is the leading factor, and K(OW) values increase with the increase of molecular surface area. Higher energy of the lowest unoccupied molecular orbital and higher net atomic charge on the oxygen atom of PBDEs result in smaller K(OW). The energy of the lowest unoccupied molecular orbital and the net atomic charge on PBDEs oxygen also play important roles in affecting the partition of PBDEs between octanol and water by influencing the interactions between PBDEs and solvent molecules.

Trans-repressive effect of NUP98-PMX1 on PMX1-regulated c-FOS gene through recruitment of histone deacetylase 1 by FG repeats.

The formation of fusion genes between NUP98 and members of the HOX family represents a critical factor for the genesis of acute leukemia or acute transformation of chronic myeloid leukemia (CML). To gain insights into the molecular mechanisms underlying the leukemogenesis of NUP98-HOX fusion products, we cloned NUP98-PMX1 from a CML-blast crisis patient with t(1;11) as a secondary chromosomal translocation, and functionally studied the fusion products in detail through various molecular and protein biochemical assays. In addition to many interesting features, we have found that the NUP98-PMX1 fusion protein exerts a repressive effect on PMX1 or serum response factor-mediated c-FOS activation, probably through the recruitment of a common corepressor histone deacetylase 1 by FG domains of the NUP98-PMX1 fusion protein. Moreover, we have provided evidence that the FG domains of NUP98-PMX1 and two other NUP98-containing fusion proteins, i.e., NUP98-HOXA9 and NUP98-HOXC11, all exhibit dual binding ability to both CREB binding protein, a coactivator, and histone deacetylase 1, a corepressor. Accordingly, we have hypothesized that this dual binding activity is shared by most, if not all, NUP98-HOX-involved fusion proteins, enabling these fusion proteins to act as both trans-activators and trans-repressors, and contributing to the genesis of acute leukemia or acute transformation of CML.

Targeting VCP enhances anticancer activity of oncolytic virus M1 in hepatocellular carcinoma.

Oncolytic virotherapy is rapidly progressing through clinical evaluation. However, the therapeutic efficacy of oncolytic viruses in humans has been less than expected from preclinical studies. We describe an anticancer drug screen for compounds that enhance M1 oncolytic virus activity in hepatocellular carcinoma (HCC). An inhibitor of the valosin-containing protein (VCP) was identified as the top sensitizer, selectively increasing potency of the oncolytic virus up to 3600-fold. Further investigation revealed that VCP inhibitors cooperated with M1 virus-suppressed inositol-requiring enzyme 1α (IRE1α)-X-box binding protein 1 (XBP1) pathway and triggered irresolvable endoplasmic reticulum (ER) stress, subsequently promoting robust apoptosis in HCC. We show that VCP inhibitor improved the oncolytic efficacy of M1 virus in several mouse models of HCC and primary HCC tissues. Finally, this combinatorial therapeutic strategy was well tolerated in nonhuman primates. Our study identifies combined VCP inhibition and oncolytic virus as a potential treatment for HCC and demonstrates promising therapeutic potential.

The investigation of mutation and single nucleotide polymorphism of receptor tyrosine kinases and downstream scaffold molecules in acute myeloid leukemia.

We investigate the role of mutations of receptor tyrosine kinases as well as their downstream scaffold molecules in leukemogenesis of acute myeloid leukemia (AML) in Chinese patients. Genes of interest included FLT3, PDGFRbeta, KDR, CSF2Rbeta, SOCS1, PIAS3 and SHIP. The coding sequence of these genes was analysed by the reverse transcription-polymerase chain reaction to search novel mutations. A novel mutation (A > T, Q1154L) of SHIP (1 of 192, 0.52%) was identified and another novel mutation (C > T, R685C) of PDGFRbeta (2 of 192, 1.04%). In addition, FLT3 mutations were seen in three of five patients with AML following myelodysplastic syndrome (60%) and 39 of 268 (14.6%) de novo AML patients (P < 0.05). No mutations were found in the coding sequence regions of KDR, CSF2Rbeta, SOCS1 or PIAS3.

Naturally Existing Oncolytic Virus M1 Is Nonpathogenic for the Nonhuman Primates After Multiple Rounds of Repeated Intravenous Injections.

Cancers figure among the leading causes of morbidity and mortality worldwide. The number of new cases is expected to rise by about 70% over the next 2 decades. Development of novel therapeutic agents is urgently needed for clinical cancer therapy. Alphavirus M1 is a Getah-like virus isolated from China with a genome of positive single-strand RNA. We have previously identified that alphavirus M1 is a naturally existing oncolytic virus with significant anticancer activity against different kinds of cancer (e.g., liver cancer, bladder cancer, and colon cancer). To support the incoming clinical trial of intravenous administration of alphavirus M1 to cancer patients, we assessed the safety of M1 in adult nonhuman primates. We previously presented the genome sequencing data of the cynomolgus macaques (Macaca fascicularis), which was demonstrated as an ideal animal species for virus infection study. Therefore, we chose cynomolgus macaques of either sex for the present safety study of oncolytic virus M1. In the first round of administration, five experimental macaques were intravenously injected with six times of oncolytic virus M1 (1 × 10(9) pfu/dose) in 1 week, compared with five vehicle-injected control animals. The last two rounds of injections were further completed in the following months in the same way as the first round. Body weight, temperature, complete blood count, clinical biochemistries, cytokine profiles, lymphocytes subsets, neutralizing antibody, and clinical symptoms were closely monitored at different time points. Magnetic resonance imaging was also performed to assess the possibility of encephalitis or arthritis. As a result, no clinical, biochemical, immunological, or medical imaging or other pathological evidence of toxicity was found during the whole process of the study. Our results in cynomolgus macaques suggested the safety of intravenous administration of oncolytic virus M1 in cancer patients in the future.