A CD38-directed, single-chain T-cell engager targets leukemia stem cells through IFN-γ-induced CD38 expression.

ABSTRACT: Treatment resistance of leukemia stem cells (LSCs) and suppression of the autologous immune system represent major challenges to achieve a cure in acute myeloid leukemia (AML). Although AML blasts generally retain high levels of surface CD38 (CD38pos), LSCs are frequently enriched in the CD34posCD38neg blast fraction. Here, we report that interferon gamma (IFN-γ) reduces LSCs clonogenic activity and induces CD38 upregulation in both CD38pos and CD38neg LSC-enriched blasts. IFN-γ-induced CD38 upregulation depends on interferon regulatory factor 1 transcriptional activation of the CD38 promoter. To leverage this observation, we created a novel compact, single-chain CD38-CD3 T-cell engager (BN-CD38) designed to promote an effective immunological synapse between CD38pos AML cells and both CD8pos and CD4pos T cells. We demonstrate that BN-CD38 engages autologous CD4pos and CD8pos T cells and CD38pos AML blasts, leading to T-cell activation and expansion and to the elimination of leukemia cells in an autologous setting. Importantly, BN-CD38 engagement induces the release of high levels of IFN-γ, driving the expression of CD38 on CD34posCD38neg LSC-enriched blasts and their subsequent elimination. Critically, although BN-CD38 showed significant in vivo efficacy across multiple disseminated AML cell lines and patient-derived xenograft models, it did not affect normal hematopoietic stem cell clonogenicity and the development of multilineage human immune cells in CD34pos humanized mice. Taken together, this study provides important insights to target and eliminate AML LSCs.

Bilateral Production Shield Enabling Highly Efficient Perovskite Photovoltaics.

Enhancing the intrinsic stability of perovskite and through encapsulation to isolate water, oxygen, and UV-induced decomposition are currently common and most effective strategies in perovskite solar cells. Here, the atomic layer deposition process is employed to deposit a nanoscale (≈100 nm), uniform, and dense Al2O3 film on the front side of perovskite devices, effectively isolating them from the erosion caused by water and oxygen in the humid air. Simultaneously, nanoscale (≈100 nm) TiO2 films are also deposited on the glass surface to efficiently filter out the ultraviolet (UV) light in the light source, which induces degradation in perovskite. Ultimately, throughthe collaborative effects of both aspects, the stability of the devices is significantly improved under conditions of humid air and illumination. As a result, after storing the devices in ambient air for 1000 h, the efficiency only declines to 95%, and even after 662 h of UV exposure, the efficiency remains at 88%, far surpassing the performance of comparison devices. These results strongly indicate that the adopted Al2O3 and TiO2 thin films play a significant role in enhancing the stability of perovskite solar cells, demonstrating substantial potential for widespread industrial applications.

[Optimal processing technology of Zhangbang vinegar-processed Olibanum with multi-indicator-response surface methodology and anticoagulant effect evaluation].

This study first optimized the processing technology for Zhangbang vinegar-processed Olibanum and investigated its in vitro anticoagulant activity. A multi-index-response surface methodology was used, with yield, powder yield, and the relative percentage of the content of six non-volatile components [11-keto-boswellic acid(KBA), 3-acetyl-11-keto-boswellic acid(AKBA), ß-elemonic acid, α-boswellic acid(α-BA), ß-boswellic acid(ß-BA), and α-acetyl-boswellic acid(α-BA)] and three volatile components(octyl acetate, incensole, and incensole acetate) as evaluation indicators. Analytical hierarchy process(AHP) combined with coefficient of variation method was used to calculate the weight of each indicator and calculate the comprehensive score(OD). Furthermore, response surface methodology was used to investigate the effects of frying temperature(A), burning time(B), rice vinegar dosage(C), and steaming time(D) on the processing technology of vinegar-processed Olibanum. Vinegar-steamed Olibanum was prepared according to the optimal processing technology for in vitro anticoagulant experiments. The results showed that the weights of octyl acetate, incensole, incensole acetate, KBA, AKBA, ß-elemonic acid, α-BA, ß-BA, α-ABA, yield, and powder yield were 0.358 2, 0.104 5, 0.146 4, 0.032 9, 0.123 7, 0.044 4, 0.022 1, 0.042 2, 0.110 1, 0.012 2, and 0.0032, respectively. The optimal processing technology for Zhangbang vinegar-processed Olibanum was as follows. Olibanum(50 g) with a particle size of 1-5 mm was continuously stir-fried at a low heat of 150-180 ℃ until in a gel-like state, ignited for burning for 15 s, sprayed with 7.5 g of rice vinegar(15%), and steamed for 3 min without fire. Subsequently, the cover was removed, and the product was continuously stir-fried at 150-180 ℃ until in a soft lump shape, removed, cooled, and crushed. The results of the in vitro anticoagulant experiments showed that compared with the blank group, both Olibanum and vinegar-processed Olibanum significantly prolonged the activated partial thromboplastin time(APTT), thrombin time(TT), and prothrombin time(PT) of rat platelet-poor plasma(PPP), and the effect of vinegar-processed Olibanum was significantly better than that of Olibanum(P<0.05). The optimized processing technology for Zhangbang vinegar-processed Olibanum is stable, feasible, and beneficial for the further development and utilization of Olibanum slices. At the same time, using the content of volatile and non-volatile components, yield, and powder yield as indicators, and verifying through pharmacological experiments, the obtained results are more reasonable and credible, and have positive guiding significance for the clinical application of characteristic processed Olibanum products.

[Mechanism of Euodiae Fructus stir-fried with water decoction of Coptidis Rhizoma in treatment of chronic colitis based on UPLC-Q-TOF-MS, network pharmacology and experimental verification].

To elucidate the mechanism of Euodiae Fructus stir-fried with water decoction of Coptidis Rhizoma in the treatment of chronic colitis, this study employed ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS), network pharmacology, and experimental verification to predict the involved targets and signaling pathways. The chronic colitis mouse model was constructed to verify the core targets. A total of 48 compounds in the herbal medicine were identified by UPLC-Q-TOF-MS. SwissTargetPrediction was used to screen the potential active components and drug targets. GeneCards, OMIM, PharmGKB, and TDD were used to search for the disease targets. A total of 31 active ingredients, 453 targets of the herbal medicine, and 3 960 targets of chronic colitis were obtained. The common targets shared by the herbal medicine and chronic colitis were introduced into STRING to construct the protein-protein interaction(PPI) network, and CytoNCA plug-in was used to screen the key targets. A total of 90 key targets were obtained, and the key active components included isorhamnetin, quercetin, limonin, and oxyberberine. GO annotation and KEGG pathway enrichment for the key targets were carried out via DAVID. The targets were mainly involved in the positive regulation of protein phosphorylation, positive regulation of nitric oxide biosynthetic process, and negative regulation of apoptotic process. The medicine may treat chronic colitis through PI3 K-Akt, VEGF, HIF-1, and TNF signaling pathways. A mouse model of chronic colitis was established and then treated with Euodiae Fructus stir-fried with the water decoction of Coptidis Rhizoma. The experimental results demonstrated that the medicine can alleviate the pathological damage of colon, significantly reduce the levels of IL-1ß, IL-6, and TNF-α, inhibit the activation of PI3 K/Akt pathway, and down-regulate the expression of VEGFA in the treatment of chronic colitis.

Targeting PRMT1-mediated FLT3 methylation disrupts maintenance of MLL-rearranged acute lymphoblastic leukemia.

Relapse remains the main cause of MLL-rearranged (MLL-r) acute lymphoblastic leukemia (ALL) treatment failure resulting from persistence of drug-resistant clones after conventional chemotherapy treatment or targeted therapy. Thus, defining mechanisms underlying MLL-r ALL maintenance is critical for developing effective therapy. PRMT1, which deposits an asymmetric dimethylarginine mark on histone/non-histone proteins, is reportedly overexpressed in various cancers. Here, we demonstrate elevated PRMT1 levels in MLL-r ALL cells and show that inhibition of PRMT1 significantly suppresses leukemic cell growth and survival. Mechanistically, we reveal that PRMT1 methylates Fms-like receptor tyrosine kinase 3 (FLT3) at arginine (R) residues 972 and 973 (R972/973), and its oncogenic function in MLL-r ALL cells is FLT3 methylation dependent. Both biochemistry and computational analysis demonstrate that R972/973 methylation could facilitate recruitment of adaptor proteins to FLT3 in a phospho-tyrosine (Y) residue 969 (Y969) dependent or independent manner. Cells expressing R972/973 methylation-deficient FLT3 exhibited more robust apoptosis and growth inhibition than did Y969 phosphorylation-deficient FLT3-transduced cells. We also show that the capacity of the type I PRMT inhibitor MS023 to inhibit leukemia cell viability parallels baseline FLT3 R972/973 methylation levels. Finally, combining FLT3 tyrosine kinase inhibitor PKC412 with MS023 treatment enhanced elimination of MLL-r ALL cells relative to PKC412 treatment alone in patient-derived mouse xenografts. These results indicate that abolishing FLT3 arginine methylation through PRMT1 inhibition represents a promising strategy to target MLL-r ALL cells.

PRMT1-mediated FLT3 arginine methylation promotes maintenance of FLT3-ITD+ acute myeloid leukemia.

The presence of FMS-like receptor tyrosine kinase-3 internal tandem duplication (FLT3-ITD) mutations in patients with acute myeloid leukemia (AML) is associated with poor clinical outcome. FLT3 tyrosine kinase inhibitors (TKIs), although effective in kinase ablation, do not eliminate primitive FLT3-ITD+ leukemia cells, which are potential sources of relapse. Thus, understanding the mechanisms underlying FLT3-ITD+ AML cell persistence is essential to devise future AML therapies. Here, we show that expression of protein arginine methyltransferase 1 (PRMT1), the primary type I arginine methyltransferase, is increased significantly in AML cells relative to normal hematopoietic cells. Genome-wide analysis, coimmunoprecipitation assay, and PRMT1-knockout mouse studies indicate that PRMT1 preferentially cooperates with FLT3-ITD, contributing to AML maintenance. Genetic or pharmacological inhibition of PRMT1 markedly blocked FLT3-ITD+ AML cell maintenance. Mechanistically, PRMT1 catalyzed FLT3-ITD protein methylation at arginine 972/973, and PRMT1 promoted leukemia cell growth in an FLT3 methylation-dependent manner. Moreover, the effects of FLT3-ITD methylation in AML cells were partially due to cross talk with FLT3-ITD phosphorylation at tyrosine 969. Importantly, FLT3 methylation persisted in FLT3-ITD+ AML cells following kinase inhibition, indicating that methylation occurs independently of kinase activity. Finally, in patient-derived xenograft and murine AML models, combined administration of AC220 with a type I PRMT inhibitor (MS023) enhanced elimination of FLT3-ITD+ AML cells relative to AC220 treatment alone. Our study demonstrates that PRMT1-mediated FLT3 methylation promotes AML maintenance and suggests that combining PRMT1 inhibition with FLT3 TKI treatment could be a promising approach to eliminate FLT3-ITD+ AML cells.

Expansion of cancer stem cell pool initiates lung cancer recurrence before angiogenesis.

Angiogenesis is essential in the early stage of solid tumor recurrence, but how a suspensive tumor is reactivated before angiogenesis is mostly unknown. Herein, we stumble across an interesting phenomenon that s.c. xenografting human lung cancer tissues can awaken the s.c. suspensive tumor in nude mice. We further found that a high level of insulin-like growth factor 1 (IGF1) was mainly responsible for triggering the transition from suspensive tumor to progressive tumor in this model. The s.c. suspensive tumor is characterized with growth arrest, avascularity, and a steady-state level of proliferating and apoptotic cells. Intriguingly, CD133+ lung cancer stem cells (LCSCs) are highly enriched in suspensive tumor compared with progressive tumor. Mechanistically, high IGF1 initiates LCSCs self-renewal from asymmetry to symmetry via the activation of a PI3K/Akt/ß-catenin axis. Next, the expansion of LCSC pool promotes angiogenesis by increasing the production of CXCL1 and PlGF in CD133+ LCSCs, which results in lung cancer recurrence. Clinically, a high level of serum IGF1 in lung cancer patients after orthotopic lung cancer resection as an unfavorable factor is strongly correlated with the high rate of recurrence and indicates an adverse progression-free survival. Vice versa, blocking IGF1 or CXCL1/PlGF with neutralizing antibodies can prevent the reactivation of a suspensive tumor induced by IGF1 stimulation in the mouse model. Collectively, the expansion of LCSC pool before angiogenesis induced by IGF1 is a key checkpoint during the initiation of cancer relapse, and targeting serum IGF1 may be a promising treatment for preventing recurrence in lung cancer patients.

Clinical significance and function of RDH16 as a tumor-suppressing gene in hepatocellular carcinoma.

AIM: Our previous transcriptome sequencing analysis detected that retinol dehydrogenase 16 (RDH16) was dramatically downregulated in hepatocellular carcinoma (HCC). RDH16 belongs to the short-chain dehydrogenases/reductases super family, and its role in HCC remains unknown. This study aimed to investigate the expression and function of RDH16 in HCC. METHODS: The mRNA and protein level of RDH16 in HCC samples were detected by quantitative real-time polymerase chain reaction and immunohistochemistry analyses, respectively. The role of RDH16 in HCC was determined by in vitro and in vivo functional studies. RESULTS: Downregulation of RDH16 has been detected in approximately 90% of primary HCCs, which was significantly associated with high serum alpha-fetoprotein level, tumor size, microsatellite formation, thrombus, and poor overall survival of HCC patients. Compared with non-tumor tissues, higher density of methylation was identified in HCC samples. In addition, RDH16 increases the level of retinoic acid and blocks the de novo synthesis of fatty acid in HCC cells. Functional study shows that ectopic expression of RDH16 in HCC cells suppresses cell growth, clonogenicity, and cell motility. CONCLUSIONS: RDH16 might be a prognostic biomarker and intervention point for new therapeutic strategies in HCC.

Evaluation of Clinical Features and Stroke Etiology in Patients with Bilateral Middle Cerebellar Peduncle Infarction.

OBJECTIVE: The aim of this study was to characterize clinical features, etiologies, and mechanisms of strokes due to bilateral middle cerebellar peduncle infarction (BMCPI). METHODS: Cases diagnosed as BMCPI in our hospital were retrieved, and a literature review was performed. Data on clinical features and brain MRI were obtained. Extracranial and intracranial segments of the vertebrobasilar artery were assessed by using digital subtraction angiography, magnetic resonance angiography, or computed tomography angiography. RESULTS: Thirteen cases (11 men and 2 women) of BMCPI were identified. A high-intensity signal of diffusion-weighted imaging sequence involving the bilateral middle cerebellar peduncle was observed in all patients. Most patients experienced vertigo, dysarthria, ataxia, and hearing disorders. Eleven of these cases were classified as large artery atherosclerosis, one as traumatic vertebral artery (VA) dissection, and one as giant cell arteritis. CONCLUSION: BMCPI is a rare cerebrovascular disease characterized by vertigo, ataxia, and dysarthria, which may also be accompanied by a hearing deficit or clinical signs of brainstem damage. BMCPI may be associated with hypoperfusion secondary to occlusive disease of the bilateral VA or proximal basilar artery.

Overexpression of MUC13, a Poor Prognostic Predictor, Promotes Cell Growth by Activating Wnt Signaling in Hepatocellular Carcinoma.

Recently RNA sequencing revealed high mucin 13 (MUC13) expression in hepatocellular carcinoma (HCC) tissues. To understand the clinicopathologic significance of MUC13 in HCC, quantitative PCR and immunohistochemistry were used to detect its expression in paired tumor tissues and nontumor tissues. The oncoprotein role of MUC13 was determined by in vitro and in vivo assays. Overexpression of MUC13 was detected in 74 of 168 primary HCC cases (44%) and was significantly associated with tumor size (P = 0.027), stage (P = 0.006), encapsulation (P = 0.044), venous invasion (P = 0.024), and poor outcome (P = 0.004). Functional studies demonstrated MUC13 had strong oncogenic activity by promoting cell growth, colony formation, cell migration, and tumor formation in nude mice. The pro-oncogenic effect of MUC13 were effectively inhibited by RNA interference. MUC13 promoted cellular G1/S phase transition by activating Wnt signaling. Mechanistically, MUC13 bound to ß-catenin and increased its phosphorylation at Ser552 and Ser675 sites, which subsequently promoted nuclear translocation of ß-catenin and up-regulation of its downstream target genes Axin2, c-Myc, and CyclinD1. Knockdown of AKT with shRNA in MUC13-overexpressing cells nullified the elevated phosphorylation of ß-catenin by MUC13. In clinical HCC samples, nuclear translocation of ß-catenin was significantly associated with MUC13 overexpression (P = 0.001). Overexpression of MUC13 plays a critical role in the development and progression of HCC by activating Wnt signaling.

Lowering Endogenous Cathepsin D Abundance Results in Reactive Oxygen Species Accumulation and Cell Senescence.

Cathepsin D is reportedly to be closely associated with tumor development, migration, and invasion, but its pathological mechanism is not fully elucidated. We aimed to evaluate phenotypic changes and molecular events in response to cathepsin D knockdown. Lowering endogenous cathepsin D abundance (CR) induced senescence in HeLa cells, leading to reduced rate of cell proliferation and impaired tumorigenesis in a mouse model. Quantitative proteomics revealed that compared with control cells (EV), the abundances of several typical lysosomal proteases were decreased in the lysosomal fraction in CR cells. We further showed that cathepsin D knockdown caused increased permeability of lysosomal membrane and reactive oxygen species accumulation in CR cells, and the scavenging of reactive oxygen species by antioxidant was able to rescue cell senescence. Despite the increased reactive oxygen species, the proteomic data suggested a global reduction of redox-related proteins in CR cells. Subsequent analysis indicated that the transcriptional activity of nuclear factor erythroid-related factor 2 (Nrf2), which regulates the expression of groups of antioxidant enzymes, was down-regulated by cathepsin D knockdown. Importantly, Nrf2 overexpression significantly reduced cell senescence. Although transient oxidative stress promoted the accumulation of Nrf2 in the nucleus, we showed that the Nrf2 protein exited nucleus if oxidative stress persisted. In addition, when cathepsin D was transiently knocked down, the cathepsin-related events followed a sequential order, including lysosomal leakage during the early stage, followed by oxidative stress augmentation, and ultimately Nrf2 down-regulation and senescence. Our results suggest the roles of cathepsin D in cancer cells in maintaining lysosomal integrity, redox balance, and Nrf2 activity, thus promoting tumorigenesis. The MS Data are available via ProteomeXchange with identifier PXD002844.

Down-regulation of POTEG predicts poor prognosis in esophageal squamous cell carcinoma patients.

POTE ankyrin domain family, member G (poteg) belongs to POTE family. The POTE family is composed of many proteins which are very closely related and expressed in prostate, ovary, testis, and placenta. Some POTE paralogs are related with some cancers. Here we showed that down-regulation of POTEG was detected in about 60% primary esophageal squamous cell carcinoma (ESCC) tumor tissues. Clinical association studies determined that POTEG down-regulation was significantly correlated with tumor differentiation, lymph nodes metastasis and TNM staging. Kaplan-Meier analysis determined that POTEG down-regulation was associated with poorer clinical outcomes of ESCC patients (P = 0.026). Functional studies showed that POTEG overexpression could suppress tumor cell growth and metastasis capacity in vitro and in vivo. Molecular analyses revealed that POTEG downregulated CDKs, leading to subsequent inhibition of Rb phosphorylation, and consequently arrested Cell Cycle at G1/S Checkpoint. POTEG overexpression induced apoptosis by activating caspases and PARP, and regulating canonical mitochondrial apoptotic pathways. On the other side, POTEG inhibited epithelial-mesenchymal transition and suppressed tumor cell metastasis. In conclusion, our study reveals a functionally important control mechanism of POTEG in esophageal cancer pathogenesis, suggesting potential use in the ESCC intervention and therapeutic strategies.

Calcium-binding protein 39 promotes hepatocellular carcinoma growth and metastasis by activating extracellular signal-regulated kinase signaling pathway.

Calcium-binding protein (CAB39) is a key regulator of a group of sterile 20 kinases. Here, we report that CAB39 was frequently up-regulated in hepatocellular carcinoma (HCC), which was significantly associated with tumor metastasis (P = 0.000), poorer disease-free survival rate (P = 0.027), and poor prognosis (P = 0.000). Ectopic expression of CAB39 in immortalized human liver cell line LO2 and HCC cell lines QGY-7703 and BEL-7402 could increase foci formation, colony formation in soft agar, tumor formation in nude mice, and cell motility. Silencing CAB39 expression in two HCC cell lines, Huh7 and MHCC97H, with short hairpin RNA could effectively abolish its oncogenic function. Further study found that CAB39 contributed to extracellular signal-regulated kinase (ERK) pathway activation, and mutations of the key sites of CAB39 markedly decrease the level of phosphorylated ERK. In addition, CAB39 could promote epithelial-mesenchymal transition by up-regulating N-cadherin and Fibronectin and down-regulating E-cadherin and α-E-catenin. As a result, ß-catenin nuclear translocation was increased and its downstream target gene, matrix metalloproteinase-9, was up-regulated. CONCLUSION: Taken together, our findings suggested that CAB39 played very important oncogenic roles in HCC pathogenesis and progression by activating the ERK signaling pathway. Better understanding of CAB39 may lead to its clinical application as a biomarker for a prognosis predictor and a novel therapeutic target. (Hepatology 2017;66:1529-1545).

PSCA acts as a tumor suppressor by facilitating the nuclear translocation of RB1CC1 in esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is an aggressive malignancy; its mechanisms of development and progression are poorly understood. By high-throughput transcriptome sequencing (RNA-Seq) profiling of three pairs of primary ESCCs and their corresponding non-tumorous tissues, we identified that prostate stem cell antigen (PSCA), a gene that encodes a glycosylphosphatidylinositol-anchored protein, is significantly downregulated in ESCC. Here, we reported decreased expression of PSCA in 188/218 (86.2%) of primary ESCC cases and was negatively regulated by its transcription factor sex-determining region Y-box5 that was significantly associated with the poor differentiation (P = 0.003), increased lymph node metastasis (P < 0.0001), advanced stage (P = 0.007), and disease-specific survival (P < 0.0001), but not associated with the recently reported transcrible rs2294008 (C > T) polymorphism in ESCC. Functional studies showed that PSCA could arrest cell cycle progression and promote cell differentiation independent of the start codon polymorphism. Further mechanistic studies revealed that retinoblastoma 1-inducible coiled-coil 1 (RB1CC1), a key signaling node to regulate cellular proliferation and differentiation, interacted specifically with PSCA in ESCC cells. Binding of PSCA and RB1CC1 in cytoplasm resulted in stabilization and translocation of RB1CC1 into nucleus, thereby activating key factors involved in cell cycle arrest and differentiation. Collectively, our data provide a novel molecular mechanism for the tumor suppressor role of PSCA and may help design effective therapy targeting PSCA-RB1CC1 pathway to control esophageal cancer growth and differentiation.

Loss of ATOH8 Increases Stem Cell Features of Hepatocellular Carcinoma Cells.

BACKGROUND & AIMS: Levels of atonal homolog 8 (ATOH8) are reduced in 48% of hepatitis B virus-associated hepatocellular carcinoma cells (HCCs). ATOH8 downregulation is associated with loss of tumor differentiation, indicating an effect mediated by cancer stem cells. We investigated the effects of loss of ATOH8 in human hepatocellular carcinoma (HCC) cells and cell lines. METHODS: HCC and adjacent nontumor tissues were collected, from 2001 through 2012, from 242 patients undergoing hepatectomy at Sun Yat-Sen University Cancer Center in China; 83% of HCCs were associated with hepatitis B virus (HBV) infection. CD133(+) cells were isolated from tumor tissues by flow cytometry. Experiments were performed in HBV-positive and HBV-negative HCC cell lines, the immortalized liver cell line LO2, and 8 other HCC cell lines. ATOH8 was expressed from lentiviral vectors in PLC8024 and Huh7 cells; levels were knocked down with small interfering RNAs in QSG7701 cells. Cells carrying empty vectors were used as controls. Gene regulation by ATOH8 was assessed in mobility shift and luciferase reporter assays. Cells were analyzed in proliferation, foci formation, and colony formation assays. The tumorigenic and chemo-resistant potential of cells were investigated by assessing growth of xenograft tumors in immunocompromised mice. Metastatic features of cells were assessed in Matrigel invasion assays and wound healing analyses. RESULTS: Levels of ATOH8 mRNA were reduced by more than 4-fold, compared to nontumor tissues, in 118 of 242 HCC samples (48.8%). Patients with tumor reductions in ATOH8 had significantly shorter times of disease-free survival (mean, 41.4 months) than patients with normal tissue levels (mean, 52.6 months). ATOH8 expression was reduced in HepG2, Huh7, PLC8024 and CRL8064 HCC cells, as well as CD133(+) cells isolated from human HCC samples. Transgenic expression of ATOH8 in HCC cell lines significantly reduced proliferation and foci colony formation, as well as their invasive and migratory abilities. Transgenic expression of ATOH8 reduced the ability of HBV-positive PLC8024 cells to form tumors in mice, compared to control cells. Cells with ATOH8 knockdown formed xenograft tumors more rapidly, in more mice, than control cells. ATOH8 repressed transcription of stem-cell associated genes including OCT4, NANOG, and CD133. Knockdown of ATOH8 in CD133-negative QSG7701 cells caused them to express CD133; acquire self-renewal, differentiation, chemo-resistance properties; form more xenograft tumors in mice; and generate induced pluripotent stem cells (based on staining for alkaline phosphatase and their ability to form embryoid bodies and teratomas). Alternatively, expression of ATOH8 in PLC8024 and Huh7 cells significantly reduced the numbers of cells expressing CD133, and increased the chemo-sensitivity of Huh7 cells to 5-fluorouracil (5-FU) and cisplatin, in vitro and in mice. CONCLUSIONS: ATOH8 appears to be a tumor suppressor that induces stem-cell features and chemoresistance in HCC cells. Strategies to restore its levels and activities might be developed to treat patients with liver cancer.

Expression of EIF5A2 associates with poor survival of nasopharyngeal carcinoma patients treated with induction chemotherapy.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a type of head-neck cancer with a distinguishable geographic and racial distribution worldwide. Increasing evidence supports that the accumulation of additional genetic and epigenetic abnormalities is important in driving the NPC tumorigenic process. In this study, we aim to investigate the association between EIF5A2 (Eukaryotic translation initiation factor 5A2) expression status and NPC clinical outcomes. METHODS: The expression status of EIF5A2 was investigated in the NPC tissue microarray. Tissues were from 166 NPC patients staging II-IV, collected between 1999 and 2005. All patients were administered 2-3 cycles of DDP (cisplatin) + 5-Fu (5-fluorouracil) induction therapy and then treated with a uniform conventional two-dimensional radiotherapy. Cell motility assay, tumor growth assay and cytotoxicity assay were performed on the EIF5A2 overexpressed cells and control cells. siRNA was also used in the in vitro studies. RESULTS: Positive staining of EIF5A2 was observed in 85.4 % (105/123) informative tumor cases. Multivariate analyses demonstrated that EIF5A2 was an independent prognostic marker of poor overall survival (OS) (P = 0.041), failure-free survival (FFS) (P = 0.029), and distant failure-free survival (D-FFS) (P = 0.043) in patients with locoregionally advanced NPC patients treated with cisplatin + 5-Fu chemoradiotherapy. The forced expression of EIF5A2 in NPC cells enhanced the cells' motility and growth ability. Knock-down of EIF5A2 in NPC cells decreased the cell's motility and growth ability. Our results also demonstrated that EIF5A2 overexpression induced chemoresistance of NPC cells to 5-Fu. CONCLUSIONS: Our findings suggested that EIF5A2 expression, as examined by immunohistochemistry, could function as an independent prognostic factor of outcomes in NPC patients with cisplatin + 5-Fu chemoradiotherapy. EIF5A2 might be a novel therapeutic target for the inhibition of NPC progress.

A Comprehensive Proteomics Analysis Reveals a Secretory Path- and Status-Dependent Signature of Exosomes Released from Tumor-Associated Macrophages.

Exosomes are 30-120 nm-sized membrane vesicles of endocytic origin that are released into the extracellular environment and play roles in cell-cell communication. Tumor-associated macrophages (TAMs) are important constituents of the tumor microenvironment; thus, it is critical to study the features and complex biological functions of TAM-derived exosomes. Here, we constructed a TAM cell model from a mouse macrophage cell line, Ana-1, and performed comparative proteomics on exosomes, exosome-free media, and cells between TAMs and Ana-1. Proteomic analysis between exosome and exosome-free fractions indicated that the functions of exosome dominant proteins were mainly enriched in RNA processing and proteolysis. TAM status dramatically affected the abundances of 20S proteasome subunits and ribosomal proteins in their exosomes. The 20S proteasome activity assay strongly indicated that TAM exosomes possessed higher proteolytic activity. In addition, Ana-1- and TAM-derived exosomes have different RNA profiles, which may result from differential RNA processing proteins. Taken together, our comprehensive proteomics study provides novel views for understanding the complicated roles of macrophage-derived exosomes in the tumor microenvironment.

Allele-specific imbalance of oxidative stress-induced growth inhibitor 1 associates with progression of hepatocellular carcinoma.

BACKGROUND & AIMS: Although there are a few highly penetrant mutations that are linked directly to cancer initiation, more less-penetrant susceptibility alleles have been associated with cancer risk and progression. We used RNA sequence analysis to search for genetic variations associated with pathogenesis of hepatocellular carcinoma (HCC). METHODS: We analyzed 400 paired HCC and adjacent nontumor tissues, along with clinical information, from patients who underwent surgery at Sun Yat-Sen University in Guangzhou, China. Total RNA was extracted from tissues and sequenced, and variations with allele imbalance were identified. Effects of variants on cell functions were investigated in HCC cell lines and tumor xenografts in mice. Variants were associated with patient outcomes. RESULTS: We found a high proportion of allele imbalance in genes related to cellular stress. A nucleotide variation in the Oxidative Stress-Induced Growth Inhibitor 1 (OSGIN1) gene (nt 1494: G-A) resulted in an amino acid substitution (codon 438: Arg-His). The variant form of OSGIN1 was specifically retained in the tumor tissues. Functional assays showed that the common form of OSGIN1 functioned as a tumor suppressor, sensitizing HCC cells to chemotherapeutic agents by inducing apoptosis. However, the variant form of OSGIN1 was less effective. It appeared to affect the translocation of OSGIN1 from the nucleus to mitochondria, which is important for its apoptotic function. The expression pattern and localization of OSGIN1 was altered in HCC specimens, compared with adjacent liver tissue. Levels of OSGIN1 messenger RNA were reduced in 24.7% of HCC specimens, and down-regulation was associated with shorter overall and disease-free survival times of patients. Patients with the OSGIN1 1494A variant had the shortest mean survival time (32.68 mo) among patient subgroups, and their tumor samples had the lowest apoptotic index. CONCLUSIONS: We identified OSGIN1 as a tumor suppressor that is down-regulated or altered in human HCCs. Variants of OSGIN1 detected in HCC samples reduce apoptosis and are associated with shorter survival times of patients.

Maelstrom promotes hepatocellular carcinoma metastasis by inducing epithelial-mesenchymal transition by way of Akt/GSK-3ß/Snail signaling.

UNLABELLED: Amplification of 1q is one of the most frequent chromosomal alterations in human hepatocellular carcinoma (HCC). In this study we identified and characterized a novel oncogene, Maelstrom (MAEL), at 1q24. Amplification and overexpression of MAEL was frequently detected in HCCs and significantly associated with HCC recurrence (P = 0.031) and poor outcome (P = 0.001). Functional study demonstrated that MAEL promoted cell growth, cell migration, and tumor formation in nude mice, all of which were effectively inhibited when MAEL was silenced with short hairpin RNA (shRNAs). Further study found that MAEL enhanced AKT activity with subsequent GSK-3ß phosphorylation and Snail stabilization, finally inducing epithelial-mesenchymal transition (EMT) and promoting tumor invasion and metastasis. In addition, MAEL up-regulated various stemness-related genes, multidrug resistance genes, and cancer stem cell (CSC) surface markers at the messenger RNA (mRNA) level. Functional study demonstrated that overexpression of MAEL increased self-renewal, chemoresistance, and tumor metastasis. CONCLUSION: MAEL is an oncogene that plays an important role in the development and progression of HCC by inducing EMT and enhancing the stemness of HCC.

Downregulation of LGI1 promotes tumor metastasis in esophageal squamous cell carcinoma.

Here, we report the characterization of a candidate tumor suppressor gene leucine-rich glioma inactivated 1 (LGI1) in human esophageal squamous cell carcinoma (ESCC). Downregulation of LGI1 has been detected in approximately 50% of primary ESCCs, which was significantly associated with advanced clinical stage (P < 0.001), lymph node metastasis (P < 0.001), tumor invasion (P = 0.009) and poor disease-specific survival (P < 0.001). Functional studies found that LGI1 could inhibit cell growth, clonogenicity, cell motility and tumor formation in nude mice. Mechanistic investigations suggested that LGI1 acted through extracellular signal-regulated kinase (ERK1/2) signaling to downregulate matrix metalloproteinase (MMP)-3 expression and subsequently suppressed tumor metastasis. Taken together, our study revealed that LGI1 plays an important tumor suppressive role in the development and progression of ESCC, with possible application in clinics as a biomarker and a potential new therapeutic target.