Characterization of the exopolysaccharide produced by Pediococcus acidilactici S1 and its effect on the gel properties of fat substitute meat mince.

Exopolysaccharide produced by lactic acid bacteria has various functions. In the present study, one anti-oxidant polysaccharide fraction, namely S1-EPS, was extracted and purified from Pediococcus acidilactici S1, and its structure and its potential effect on the gel properties of fat substitute meat mince were investigated. The results showed that S1-EPS, one of homogeneous polysaccharides, was mainly composed of Gal, Glc, and Man in molar ratio of 7.61: 15.25: 77.13 and molecular weight of 46.975 kDa. The backbone of EPS-S1 contained →2,6)-α-D-Manp-(1→，→2)-α-D-Manp-(1→,→3)-α-D-Glcp-(1 → and a small amount of→6)-ß-D-Manp-(1→. The linkages of branches in EPS-S1 were mainly composed of α-D-Manp-(1→ attached to a sugar residue →2,6)-α-D-Manp-(1→O-2 or ß-D-Galp-(1→ attached to a sugar residue →2,6)-α-D-Manp-(1→O-6. Furthermore, as S1-EPS increased, the meat minced gel pores decreased, and the surface became smooth. A remarkable inhibitory effect on the lipid oxidation of meat minced gel was found as S1-EPS concentration increased. Overall, S1-EPS was found to have substantial potential in low-fat meat products by serving as a natural, anti-oxidant, and functional additive.

Sulforaphene suppresses oesophageal cancer growth through mitogen- and stress-activated kinase 2 in a PDX mouse model.

BACKGROUND: Although sulforaphene has potential anticancer effects, little is known about its effect on oesophageal squamous cell carcinoma (ESCC) invasiveness. METHODS: To investigate whether sulforaphene inhibits the growth of oesophageal cancer cells, MTT and anchorage-independent cell growth assays were performed. Global changes in the proteome and phosphoproteome of oesophageal cancer cells after sulforaphene treatment were analysed by mass spectrometry (MS), and the underlying molecular mechanism was further verified by in vivo and in vitro experiments. RESULTS: Sulforaphene treatment markedly affected proteins that regulate several cellular processes in oesophageal cancer cells, and mitogen- and stress-activated kinase 2 (MSK2) was the main genetic target of sulforaphene in reducing the growth of oesophageal cancer cells. Sulforaphene significantly suppressed ESCC cell proliferation in vitro and reduced the tumour size in an oesophageal patient-derived xenograft (PDX) SCID mouse model. Furthermore, the binding of sulforaphane to MSK2 in vitro was verified using a cellular thermal dhift assay, and the effect of MSK2 knockdown on the ESCC phenotype was observed using a shMSK2 model. CONCLUSION: The results showed that sulforaphene suppresses ESCC growth in both human oesophageal squamous cells and PDX mouse model by inhibiting MSK2 expression, implicating sulforaphene as a promising candidate for ESCC treatment.

A Thermally Stable Recombinant Human Fibronectin Peptide-Fused Protein (rhFN3C) for Faster Aphthous Ulcer (AU) Healing.

Approximately 59.4-100% of head and neck cancer patients receiving radiotherapy or radio chemotherapy suffer from aphthous ulcers (AUs), which seriously affect the subsequent treatment. At the same time, AUs are a common oral mucosal disease with a high incidence rate among the population, often accompanied by severe pain, and affect both physical and mental health. Strategies to increase the ulcer healing rate and relieve pain symptoms quickly is a long-term clinical objective. Oral mucosal discontinuity is the main histological hallmark of AUs. So, covering the inner mucosal defect with an in vitro engineered oral mucosal equivalent shows good prospects for AU alleviation. Fibronectin (FN) is a glycopeptide in the extracellular matrix and exhibits opsonic properties, aiding the phagocytosis and clearance of foreign pathogens through all stages of ulcer healing. But native FN comes from animal blood, which has potential health risks. rhFN3C was designed with multi-domains of native FN, whose core functions are the recruitment of cells and growth factors to accelerate AU healing. rhFN3C is a peptide-fused recombinant protein. The peptides are derived from the positions of 1444-1545 (FNIII10) and 1632-1901 (FNIII12-14) in human native FN. We optimized the fermentation conditions of rhFN3C in E. coli BL21 to enable high expression levels. rhFN3C is thermally stable and nontoxic for L929, strongly promotes the migration and adhesion of HaCaT, decreases the incidence of wound infection, and shortens the mean healing time by about 2 days compared to others (p < 0.01). rhFN3C may have great potential for use in the treatment of AUs. The specific methods and mechanisms of rhFN3C are yet to be investigated.

BRD4 drives esophageal squamous cell carcinoma growth by promoting RCC2 expression.

The low survival rate of esophageal squamous cell carcinoma patients is primarily attributed to technical limitations and a lack of insight regarding the molecular mechanisms contributing to its progression. Alterations in epigenetic modulators are critical to cancer development and prognosis. BRD4, a chromatin reader protein, plays an essential role in regulating oncogene expression. Here, we investigated the contributing role of BRD4 and its related mechanisms in the context of ESCC tumor progression. Our observations showed that BRD4 transcript and protein expression levels are significantly increased in ESCC patient tissues. Genetic or pharmacological inhibition of BRD4 suppressed ESCC cell proliferation in vitro and in vivo. Proteomic and transcriptomic analyses were subsequently used to deduce the potential targets of BRD4. Mechanistic studies showed that RCC2 is a downstream target of BRD4. Inhibition of either BRD4 or RCC2 resulted in decreased ESCC cell proliferation. The BRD4-TP73 interaction facilitated the binding of BRD4 complex to the promoter region of RCC2, and subsequently modulated RCC2 transcription. Furthermore, targeting BRD4 with inhibitors significantly decreased tumor volume in ESCC PDX models, indicating that BRD4 expression may contribute to tumor progression. Collectively, these findings suggest that BRD4 inhibition could be a promising strategy to treat ESCC by downregulating RCC2.

Discovery of a novel dual-target inhibitor against RSK1 and MSK2 to suppress growth of human colon cancer.

Colon cancer is the most aggressive tumor in both men and women globally. As many the chemotherapeutic regimens have adverse side effects and contribute to the resistance and recurrence, therefore, finding novel therapeutic targets and developing effective agents are urgent. Based on the TCGA and GTEx database analysis, RSK1 and MSK2 were found abnormal expressed in colon cancer. RSK1 and MSK2 were overexpressed in colon cancer tissues confirmed by western blot and IHC. After knocking down RSK1 or MSK2, cell proliferation and anchorage-independent cell growth were markedly inhibited. Using a computer docking model, we identified a novel dual-target inhibitor, APIO-EE-07, that could block both RSK1 and MSK2 kinase activity in a dose-dependent manner. APIO-EE-07 inhibited cell growth and induced apoptosis and also increased expression of Bax as well as cleaved caspase-3 and -PARP in colon cancer cells by downregulating RSK1 and MSK2 downstream targets, including CREB and ATF1. Furthermore, APIO-EE-07 decreased tumor volume and weight in human patient-derived xenografts tumors implanted in SCID mice. In summary, our results demonstrate that RSK1 and MSK2 are the potential targets for the treatment of colon cancer. APIO-EE-07, a novel dual-target inhibitor of RSK1 and MSK2, can suppress the growth of colon cancer by attenuating RSK1 and MSK2 signaling.

Icariin Ameliorates Lower Back Pain in Rats via Suppressing the Secretion of Cytokine-Induced Neutrophil Chemoatractant-1.

PURPOSE: To investigate whether icariin (ICA), a well-known medicine extracted from the stem and leaf of Epimedium brevicornum Maxim, had analgesic effect on lower back pain (LBP) in rats. METHODS: In a puncture-induced LBP rat model, the severity of LBP was quantified using the paw/foot withdrawal threshold method after intragastric administration of ICA at a dosage of 50 mg/kg/d or 100 mg/kg/d. The pain-related peptides of substance P (SP) and calcitonin gene-related peptide (CGRP) were also measured in intervertebral disc (IVD) tissue using RT-PCR after ICA treatment. In addition, the expression of cytokine-induced neutrophil chemoattractant-1 (CINC-1) in IVD was quantified using RT-PCR and ELISA examination. RESULTS: ICA treatment resulted in a significant amelioration of mechanical allodynia in a dose-response manner, and the analgesic effect could last for two weeks even during the washout period. More importantly, the mechanism of analgesic pharmacological effect in ICA was to suppress the upregulated CINC-1, the homolog of IL-8 in rats, which is a crucial proalgesic factor contributing to LBP, in IVDs. CONCLUSION: ICA is a novel herbal extract to relieve LBP, and it may be a promising alternative pain killer in the future.

Decrypting the Molecular Mechanistic Pathways Delineating the Chemotherapeutic Potential of Ruthenium-Phloretin Complex in Colon Carcinoma Correlated with the Oxidative Status and Increased Apoptotic Events.

To explore fresh strategies in colorectal cancer (CRC) chemotherapy, we evaluated the capability of the ruthenium-phloretin complex in exterminating colon cancer by effectively addressing multiple apoptotic mechanisms on HT-29 cancer cells together with an animal model of colorectal cancer activated by 1,2-dimethylhydrazine and dextran sulfate sodium. Our current approach offers tangible evidence of the application of the ruthenium-phloretin complex in future chemotherapy. The complex triggers intrinsic apoptosis triggered by p53 and modulates the Akt/mTOR pathway along with other inflammatory biomarkers. The ruthenium-phloretin complex has been synthesized and successfully characterized by numerous spectroscopic methodologies accompanied by DPPH, FRAP, and ABTS assays assessing its antioxidant potential. Studies conducted in human cell lines revealed that the complex improved levels of p53 and caspase-3 while diminishing the activities of VEGF and mTOR, triggers apoptosis, and induces fragmentation of DNA in the HT-29 cells. Toxicity studies were conducted to identify the therapeutic doses of the novel complex in animal models. The outcomes of the in vivo report suggest that the complex was beneficial in repressing multiplicity of aberrant crypt foci as well as hyperplastic lesions and also promoted increased levels of CAT, SOD, and glutathione. In addition, the ruthenium-phloretin complex was able to control cell proliferation and boosted apoptotic outbursts in cancer cells associated with the increase in cellular response towards Bax while diminishing responses towards Bcl-2, NF-κB, and MMP-9. Our observations from the experiments deliver testament that the ruthenium-phloretin complex has the potential to act as a promising chemotherapeutic agent in colorectal cancer because it can affect the growth of ACF and hyperplastic abrasions in the colon tissues by evoking cell death.

Cytokine Signature Induced by SARS-CoV-2 Spike Protein in a Mouse Model.

Although COVID-19 has become a major challenge to global health, there are currently no efficacious agents for effective treatment. Cytokine storm syndrome (CSS) can lead to acute respiratory distress syndrome (ARDS), which contributes to most COVID-19 mortalities. Research points to interleukin 6 (IL-6) as a crucial signature of the cytokine storm, and the clinical use of the IL-6 inhibitor tocilizumab shows potential for treatment of COVID-19 patient. In this study, we challenged wild-type and adenovirus-5/human angiotensin-converting enzyme 2-expressing BALB/c mice with a combination of polyinosinic-polycytidylic acid and recombinant SARS-CoV-2 spike-extracellular domain protein. High levels of TNF-α and nearly 100 times increased IL-6 were detected at 6 h, but disappeared by 24 h in bronchoalveolar lavage fluid (BALF) following immunostimulant challenge. Lung injury observed by histopathologic changes and magnetic resonance imaging at 24 h indicated that increased TNF-α and IL-6 may initiate CSS in the lung, resulting in the continual production of inflammatory cytokines. We hypothesize that TNF-α and IL-6 may contribute to the occurrence of CSS in COVID-19. We also investigated multiple monoclonal antibodies (mAbs) and inhibitors for neutralizing the pro-inflammatory phenotype of COVID-19: mAbs against IL-1α, IL-6, TNF-α, and granulocyte-macrophage colony-stimulating factor (GM-CSF), and inhibitors of p38 and JAK partially relieved CSS; mAbs against IL-6, TNF-α, and GM-CSF, and inhibitors of p38, extracellular signal-regulated kinase, and myeloperoxidase somewhat reduced neutrophilic alveolitis in the lung. This novel murine model opens a biologically safe, time-saving avenue for clarifying the mechanism of CSS/ARDS in COVID-19 and developing new therapeutic drugs.

Inhibition of LTA4H by bestatin in human and mouse colorectal cancer.

BACKGROUND: Our preclinical data showed that the leukotriene A4 hydrolase (LTA4H) pathway plays a role in colorectal cancer (CRC). High expression of LTA4H and leukotriene B4 receptor type 1 (BLT1) were also associated with CRC survival probability. Clinical samples were evaluated to determine whether LTA4H could serve as a therapeutic target and whether leukotriene B4 (LTB4) could be used as a biomarker for evaluating the efficacy of bestatin in CRC. METHODS: Patients with Stage I-III CRC did or did not receive bestatin prior to surgery. Evaluable pairwise CRC patient blood samples were collected to evaluate LTB4 concentration. Tissues were processed by immunohistochemistry to detect the LTA4H pathway and Ki-67 expression. We also determined whether LTA4H or BLT1 was associated with CRC survival probability and explored the mechanism of bestatin action in CRC. FINDINGS: Samples from 13 CRC patients showed a significant decrease in LTB4, the LTA4H signaling pathway, and Ki-67 in the bestatin-treated group compared with the untreated group. LTA4H and BLT1 are overexpressed in CRC and associated with CRC survival probability. Bestatin effectively inhibited LTB4 and tumorigenesis in the ApcMin/+ and CRC patient-derived xenograft mouse model. INTERPRETATION: These results demonstrate that LTB4 could serve as a biomarker for evaluating bestatin efficacy in CRC and the antitumor effects of bestatin through its targeting of LTA4H and support further studies focusing on LTA4H inhibition in CRC.

Naringenin inhibits migration of breast cancer cells via inflammatory and apoptosis cell signaling pathways.

BACKGROUND: Naringenin, a flavonoid compound, has a wide variety of uses in the pharmaceutical industry for its antioxidant and anti-inflammatory potential. OBJECTIVES: The current experiment aimed to investigate the anticancer effect of naringenin in triple-negative human breast cancer cells (MDA-MR-231) and an animal model with 7,12-dimethylbenz[a] anthracene (DMBA)-induced breast cancer in female rats to determine the mechanisms and molecular targets. METHODS: The cytotoxic effects of naringenin against MDA-MB-231 cells were assessed by MTT assay. Apoptosis and cell cycle alterations were analyzed via flow cytometry. Morphological and biochemical changes in DMBA-induced cancer with naringenin treatment were assayed using our protocol. The potential mechanisms of action were verified via qRT-PCR. RESULTS: Naringenin was found to inhibit cell proliferation in a time- and concentration-dependent manner. This effect was associated with cell cycle arrest at the G0/G1 phase, along with apoptosis and deposition at the sub-G1 phase (75%). Treatment with naringenin reduced tumor incidence (45.55, 40, and 27.67%) and tumor burden (78.7, 35.4, and 1.2 g) in a dose-dependent manner. Naringenin treatment altered the biochemical and antioxidant parameters related to inflammation necessary for anticancer activity. The qRT-PCR studies further confirmed the mitochondrial-mediated apoptotic effects of naringenin. CONCLUSION: On the basis of these results, we can conclude that naringenin exerts an anticancer effect in the MDA-MB-231 cell line that arrests cell development at the G0/G1 phase, and in vivo it alters the mitochondrial-mediated intrinsic pathway responsible for apoptosis.

Aurora B kinase as a novel molecular target for inhibition the growth of osteosarcoma.

Osteosarcoma is the primary human malignant tumor affecting bone. This cancer most frequently arises in children and adolescents, with a second peak in those over the age of 50. Currently, surgery followed by radiotherapy and chemotherapy are the main treatments, but long-term positive effects are very poor. Aurora B kinase is a serine/threonine kinase that is a key regulator of cell cycle and mitosis. Tissue array analysis revealed that Aurora B kinase is overexpressed in osteosarcoma compared with normal bone tissue. We developed a compound, HOI-07 (i.e., (E)-3-((E)-4-(benzo[d] [1,3]dioxol-5-yl)-2-oxobut-3-en-1-ylidene)indolin-2-one), as a specific Aurora B kinase inhibitor and examined its effectiveness against osteosarcoma cell growth in this study. This compound inhibited Aurora B kinase activity in osteosarcoma and induced apoptosis, caused G2-M phase arrest, and attenuated osteosarcoma anchorage-independent cell growth. Moreover, knocking down the expression of Aurora B effectively reduced the sensitivity of osteosarcoma to HOI-07. Results of a xenograft mouse study indicated that HOI-07 treatment effectively suppressed the growth of 143B and KHOS xenografts, without affecting the body weight of mice. The expression of phosphorylated histone H3 (Ser10) was reduced in mice treated with HOI-07. Overall, we identified HOI-07 as a specific Aurora B kinase inhibitor for osteosarcoma treatment and this compound warrants further investigation.

ELK1-induced upregulation of long non-coding RNA MIR100HG predicts poor prognosis and promotes the progression of osteosarcoma by epigenetically silencing LATS1 and LATS2.

Osteosarcoma (OS) is the commonest malignant bone tumor in the world. High incidence of OS has gradually become a social problem. Recent years, numerous studies have revealed that long non-coding RNAs (lncRNAs) are crucial regulators in the tumor progression. As a member of lncRNA family, MIR100HG has been reported to be an oncogene in breast cancer and acute megakaryoblastic leukemia. Nevertheless, the specific role of MIR100HG in osteosarcoma is still unclear. In this study, we investigated the biological function and molecular mechanism of MIR100HG in the progression of osteosarcoma. At first, we measured the high expression of MIR100HG in OS tissues and cell lines by qRT-PCR. Kaplan-Meier method revealed that high expression of MIR100HG is a factor for the poor prognosis of OS patients (P = 0.004). To explore the effect of MIR100HG on the biological processes of OS, loss-of-function assays were conducted in OS cells. Functionally, MIR100HG knockdown suppressed cell proliferation, cell cycle progression while promoted cell apoptosis. Mechanistically, MIR100HG was upregulated by the transcription factor ELK1. The upregulation of MIR100HG led to the inactivation of Hippo pathway. Furthermore, we found that MIR100HG inactivated Hippo pathway in OS cells by epigenetically silencing LATS1 and LATS2. Rescue assays demonstrated that LATS1/2 involved in MIR100HG-mediated OS progression. In summary, our study indicated that ELK1-induced upregulation of MIR100HG promoted OS progression by epigenetically silencing LATS1 and LATS2 and inactivating Hippo pathway.

Resveratrol suppresses colon cancer growth by targeting the AKT/STAT3 signaling pathway.

Colon cancer is a common type of cancer worldwide and accounts for a significant number of cancer­related deaths. Although surgical techniques and treatment strategies for colon cancer have advanced over the past two decades, the prognosis has not improved considerably. Resveratrol, a natural stilbene compound, possesses antioxidant, cardioprotective and anticancer properties. However, the role of resveratrol in colon cancer has not been fully elucidated. The present study demonstrated that resveratrol inhibited cell proliferation and colony growth in DLD1 and HCT15 colon cancer cells, but did not affect normal colon epithelial cells. The resveratrol­mediated inhibition of cell proliferation correlated with an induction of apoptosis and with G1 phase cell cycle arrest in colon cancer cells. Additionally, resveratrol treatment decreased the protein expression levels of cyclin D1, cyclin E2 and BCL2 apoptosis regulator, while it increased BCL2 associated X and tumor protein p53, all of which are involved in the regulation of cell cycle and apoptosis. Notably, the results obtained from in silico computational screening identified AKT serine/threonine kinase 1 (AKT1) and AKT2 as novel targets of resveratrol. Computational docking suggested that there are three or four possible hydrogen bonds in the active pocket of AKT1 and AKT2 that contribute to the mode of action of resveratrol. The present study confirmed that resveratrol bound to AKT1 and AKT2 with a pull­down assay. Furthermore, knockdown of AKT1 and AKT2 inhibited cell proliferation and colony growth, by attenuating cell cycle progression and increasing apoptosis in colon cancer cells, effects that were similar to those caused by resveratrol treatment. Taken together, the present results suggest that the targeting effects of resveratrol to AKT1 and AKT2 may be a potent strategy for chemoprevention or therapy for colon cancer.

Sulforaphene induces apoptosis and inhibits the invasion of esophageal cancer cells through MSK2/CREB/Bcl-2 and cadherin pathway in vivo and in vitro.

BACKGROUND: As a novel type of isothiocyanate derived from radish seeds from cruciferous vegetables, sulforaphene (SFE, 4-methylsufinyl-3-butenyl isothiocyanate) has various important biological effects, such as anti-oxidative and anti-bacterial effects. Recently, sulforaphene has attracted increasing attention for its anti-tumor effects and its ability to suppress the development of multiple tumors through different regulatory mechanisms. However, it has not yet been widely investigated for the treatment of esophageal cancer. METHODS: We observed an increased apoptosis in esophageal cancer cells on sulforaphene treatment through flow cytometry (FCM) analysis and transmission electron microscopy (TEM). Through mass spectrometry (MS) analysis, we further detected global changes in the proteomes and phosphoproteomes of esophageal cancer cells on sulforaphene treatment. The molecular mechanism of sulforaphene was verified by western blot,the effect and mechanism of SFE on esophageal cancer was further verified by patient-derived xenograft mouse model. RESULTS: We identified multiple cellular processes that were changed after sulforaphene treatment by proteomics. We found that sulforaphene could repress the phosphorylation of CREB through MSK2, leading to suppression of Bcl-2 and further promoted cell apoptosis. Additionally, we confirmed that sulforaphene induces tumor cell apoptosis in mice. Interestingly, we also observed the obvious inhibition of cell migration and invasion caused by sulforaphene treatment by inhibiting the expression of cadherin, indicating the complex effects of sulforaphene on the development of esophageal cancer. CONCLUSIONS: Our data demonstrated that sulforaphene induced cell apoptosis and inhibits the invasion of esophageal cancer through a mechanism involving the inhibition of the MSK2-CREB-Bcl2 and cadherin pathway. Sulforaphene could therefore serve as a promising anti-tumor drug for the treatment of esophageal cancer.

Human umbilical vein endothelial cell vaccine suppresses the angiogenesis of esophageal squamous cell carcinoma in a humanized mouse model.

The antitumor effect of the human umbilical vein endothelial cell (HUVEC) vaccine has been well documented; however, its anti­angiogenic effects on human esophageal squamous cell carcinoma (ESCC) have yet to be studied. In the present study, a 'humanized' mouse model was established by transplanting NOD/SCID mice with human peripheral blood mononuclear cells (PBMC). After 4 weeks, the level of cluster of differentiation (CD)­45+ human T­lymphocytes in mouse peripheral blood was >0.1%, which indicated that mouse reconstruction and the human immune system transformation had been successful. The humanized mice were used to evaluate the anti­angiogenic effect of the HUVEC vaccine on human ESCC. After immunization with the HUVEC vaccine for 5 consecutive weeks, the humanized mice were subcutaneously transplanted with EC9706 cells. The results indicated that the HUVEC vaccine reduced the size of human esophageal carcinoma xenografts by suppressing angiogenesis. In addition, the HUVEC­immunized mice exhibited reduced expression of angiogenesis­associated antigens (vascular endothelial growth factor receptor 2 and VE­Cadherin) in the tumor specimens, and increased levels of angiogenesis­associated antibodies in the serum. Notably, the HUVEC vaccine also increased the infiltration of human T­lymphocytes into the spleen of humanized mice. In conclusion, the present study demonstrated the anti­angiogenic effect of the HUVEC vaccine on ESCC in a humanized mouse model, and set an experimental foundation for the application of the HUVEC vaccine in ESCC patients.

RSK2 is required for TRAF6 phosphorylation-mediated colon inflammation.

Inflammation is a complex biological host reaction to tissue damage, infection and trauma. Extensive study of the inflammatory response has led to the identification of several protein kinases that are essential for signaling and could be potential therapeutic targets. The RSK family of kinases has multiple cellular functions. In our study, we found that RSK2 is a mediator for inflammation signaling and interacts with TRAF6. In vitro kinase assay results indicated that RSK2 strongly phosphorylates TRAF6 at serines 46, 47 and 48. Ectopic overexpression of TRAF6 or knocking down RSK2 expression confirmed that RSK2 is a positive regulator of TRAF6 K63 ubiquitination. TRAF6 is also required for RSK2 ubiquitination. TRAF6 bridges the TNF receptor superfamily and intracellular signaling for the induction of proinflammatory cytokines. We developed a colon inflammation model using RSK2 wild type (WT) and knockout (KO) mice. As expected, F4/80 and CD3 infiltration were significantly upregulated in WT mice compared to RSK2 KO mice. Furthermore, inflammation signaling, including Ikkα/ß, p38 and JNKs, was dramatically upregulated in WT mice. Colon tissue immunoprecipitation results further confirmed that TRAF6 K63 ubiquitination was lower in RSK2 KO mice. Overall, these results indicate that phosphorylation of TRAF6 (S46, 47, 48) by RSK2 is required for TRAF6 K63 ubiquitination and inflammation signaling.

Metformin inhibits esophageal squamous cell carcinoma-induced angiogenesis by suppressing JAK/STAT3 signaling pathway.

Although it has been known that the tumor microenvironment affects angiogenesis, the precise mechanism remains unclear. In this study, we simulated the microenvironment of human esophageal squamous cell carcinoma (ESCC) by tumor conditioned medium (TCM) to assess the influence on normal endothelial cells (NECs). We found that the TCM-induced NECs showed enhanced angiogenic properties, such as migration, invasion and tube formation. Moreover, the TCM-induced NECs expressed tumor endothelial cells (TECs) markers at higher levels, which indicated that TCM probably promoted tumor angiogenesis by coercing NECs to change toward TECs. The microarray gene expression analysis indicated that TCM induced great changes in the genome of NECs and altered many regulatory networks, especially c-MYC and JAK/STAT3 signaling pathway. More importantly, we investigated the anti-angiogenic effect of metformin, and found that metformin abrogated the ESCC microenvironment-induced transition of NECs toward TECs by inhibiting JAK/STAT3/c-MYC signaling pathway. Furthermore, we verified the anti-angiogenic activity of metformin in vivo by a human ESCC patient-derived xenograft (PDX) mouse model for the first time. Taken together, our research provides a novel mechanism for the anti-angiogenic effect of metformin, and sets an experimental basis for the development of new anti-angiogenic drugs by blocking the transition of NECs toward TECs, which possibly open new avenues for targeted treatment of cancer.

APIO-EE-9 is a novel Aurora A and B antagonist that suppresses esophageal cancer growth in a PDX mouse model.

Esophageal cancer (EC) is one of the most aggressive malignancies of the upper aerodigestive tract. Over the past three decades, with advances in surgical techniques and treatment, the prognosis of esophageal cancer has only slowly improved. Thus identifying novel molecular targets and developing therapeutic agents are critical. Aurora kinases play a crucial role in mitosis and selective inhibitors might provide an effective therapeutic treatment for cancer. However, the role of Aurora kinases in EC is still inadequately studied. Here, we identified a novel compound, referred to as APIO-EE-9, which inhibits growth and colony formation and induces apoptosis of esophageal cancer cells. Using computer modeling, we found that APIO-EE-9 interacted with both Aurora A and B in the ATP-binding pocket. APIO-EE-9 inhibited both Aurora A and B kinase activities in a dose-dependent manner. Treatment with APIO-EE-9 substantially reduced the downstream Aurora kinase phosphorylation of histone H3 (Ser10), resulting in formation of multiple nuclei and centrosomes. Additionally, esophageal cancer cells expressing shAurora A or shAurora B kinase exhibited a dramatic reduction in proliferation and colony formation. Injection of these cells as xenografts in mice reduced tumor formation compared to wildtype cells. Importantly, APIO-EE-9 significantly decreased the size of esophageal patient-derived xenograft (PDX) tumors implanted in SCID mice. These results demonstrated that APIO-EE-9 is a specific Aurora kinase inhibitor that could be developed as a therapeutic agent against esophageal cancer.

Dendritic cells loading autologous tumor lysate promote tumor angiogenesis.

Dendritic cells (DC) have been exploited for vaccination against cancer for years. DC loading autologous tumor lysate (ATL-DC) have been assessed in ongoing clinical trials, but frequently do not meet expectation. In this study, we found that mice immunized with ATL-DC induced less protective anti-tumor effect than immunized with DC alone. The percentage of CD8+ T cells and the lysis efficiency of CTLs to auto tumor cells in ATL-DC vaccination group was less than that of DC group. Moreover, vaccination of mice with ATL-DC also promoted tumor angiogenesis by analyzing the CD31 positive microvessel density and hemoglobin content of tumor specimens. Human umbilical vein endothelial cells (HUVEC) have been proved effective in the anti-angiogenesis immunity against cancer. However, in the following research we found that the anti-tumor effect was attenuated while immunized mice with HUVEC combined with ATL-DC (HUVEC + ATL-DC). Furthermore, immunized mice with HUVEC + ATL-DC profoundly increased the tumor angiogenesis by analyzing the microvessel density and hemoglobin content of tumor specimens. These data suggest that vaccination using ATL-DC antagonized HUVEC induced anti-angiogenesis effect. Our research for the first time indicated that ATL-DC have the potential to promote the process of tumor angiogenesis in vivo. As vaccines based on DC loading autologous tumor lysate have been used in clinical, this find warned that the safety of this kind of vaccine should be taken into consideration seriously.