Nanoparticles with rough surface improve the therapeutic effect of photothermal immunotherapy against melanoma

Photothermal therapy has been intensively investigated for treating cancer in recent years. However, the long-term therapeutic outcome remains unsatisfying due to the frequently occurred metastasis and recurrence. To address this challenge, immunotherapy has been combined with photothermal therapy to activate anti-tumor immunity and relieve the immunosuppressive microenvironment within tumor sites. Here, we engineered silica-based core‒shell nanoparticles (JQ-1@PSNs-R), in which silica cores were coated with the photothermal agent polydopamine, and a bromodomain-containing protein 4 (BRD4) inhibitor JQ-1 was loaded in the polydopamine layer to combine photothermal and immune therapy for tumor elimination. Importantly, to improve the therapeutic effect, we increased the surface roughness of the nanoparticles by hydrofluoric acid (HF) etching during the fabrication process, and found that the internalization of JQ-1@PSNs-R was significantly improved, leading to a strengthened photothermal killing effect as well as the increased intracellular delivery of JQ-1. In the animal studies, the multifunctional nanoparticles with rough surfaces effectively eradicated melanoma via photothermal therapy, successfully activated tumor-specific immune responses against residual tumor cells, and further prevented tumor metastasis and recurrence. Our results indicated that JQ-1@PSNs-R could serve as an innovative and effective strategy for combined cancer therapy.

Diversified Application of Barcoded PLATO (PLATO-BC) Platform for Identification of Protein Interactions / 基因组蛋白质组与生物信息学报·英文版

Proteins usually associate with other molecules physically to execute their functions. Identifying these interactions is important for the functional analysis of proteins. Previously, we reported the parallel analysis of translated ORFs (PLATO) to couple ribosome display of full-length ORFs with affinity enrichment of mRNA/protein/ribosome complexes for the "bait" molecules, followed by the deep sequencing analysis of mRNA. However, the sample processing, from extraction of precipitated mRNA to generation of DNA libraries, includes numerous steps, which is tedious and may cause the loss of materials. Barcoded PLATO (PLATO-BC), an improved platform was further developed to test its application for protein interaction discovery. In this report, we tested the antisera-antigen interaction using serum samples from patients with inclusion body myositis (IBM). Tripartite motif containing 21 (TRIM21) was identified as a potentially new IBM autoantigen. We also expanded the application of PLATO-BC to identify protein interactions for JQ1, single ubiquitin peptide, and NS5 protein of Zika virus. From PLATO-BC analyses, we identified new protein interactions for these "bait" molecules. We demonstrate that Ewing sarcoma breakpoint region 1 (EWSR1) binds to JQ1 and their interactions may interrupt the EWSR1 association with acetylated histone H4. RIO kinase 3 (RIOK3), a newly identified ubiquitin-binding protein, is preferentially associated with K63-ubiquitin chain. We also find that Zika NS5 protein interacts with two previously unreported host proteins, par-3 family cell polarity regulator (PARD3) and chromosome 19 open reading frame 53 (C19orf53), whose attenuated expression benefits the replication of Zika virus. These results further demonstrate that PLATO-BC is capable of identifying novel protein interactions for various types of "bait" molecules.

The Bromodomain Inhibitor JQ1 Enhances the Responses to All-trans Retinoic Acid in HL-60 and MV4-11 Leukemia Cells

All-trans retinoic acid (ATRA) is a highly effective treatment for acute promyelocytic leukemia (APL), a cytogenetically distinct subtype of acute myeloid leukemia (AML). However, ATRA-based treatment is not effective in other subtypes of AML. In non-APL AML, ATRA signaling pathway is impaired or downmodulated, and consequently fails to respond to pharmacological doses of ATRA. Therefore, complementary treatment strategies are needed to improve ATRA responsiveness in non-APL AML. In this study, we investigated the combined effect of ATRA and bromodomain inhibitor JQ1, proven to have potent anti-cancer activity mainly through inhibition of c-Myc. We showed that the combination of ATRA with JQ1 synergistically inhibited proliferation of AML cells. The synergistic growth inhibition was resulted from differentiation or apoptosis depending on the kind of AML cells. Concomitantly, the combined treatment of ATRA and JQ1 caused greater depletion of c-Myc and hTERT expression than each agent alone in AML cells. Taken together, these findings support the rationale for the use of the combination of ATRA and JQ1 as a therapeutic strategy for the treatment of AML.

Inhibitory effect of JQ1 on proliferation of acute myeloid leukemia U937 cell line and its effect on the signal transduction pathway of STAT-5 / 白血病·淋巴瘤

Objective To study the suppressive mechanism of the bromo structural domain inhibitor JQ1 on the acute myeloid leukemia cell line U937 and its regulation of the STAT-5 signaling pathway. Methods U937 cells in the logarithmic growth phase were tested. Each experimental group was fed with 0.2, 1.0 and 4.0μmol/L of JQ1, and a blank control group without JQ1 was set up. U937 cells were cultured for 48 h, and the cell proliferation inhibitory rate was measured by MTT assay. Flow cytometry (FCM) was used to detect the apoptotic rate. Real-time fluorescence quantitative polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of focal adhesion kinase (FAK) and P21 activated kinase (PAK1). The expression of STAT-5 protein was analyzed by Western blot. Results Different concentration of JQ1 could inhibit the proliferation of U937 cells in a time and dose-dependent manner, and different concentration of JQ1 could induce the apoptosis of U937 cells in a dose-dependent manner. Treatment of U937 cells with different concentrations of JQ1 (0.2, 1.0 and 4.0 μmol/L) reduced the expression of FKA mRNA and PAK1 mRNA after 48 h, the expression of FAK mRNA was 0.417±0.066, 0.140±0.026, and 0.027±0.006 (F=454.651, P=0.000), and the expression of PAK1 mRNA was 0.533±0.045, 0.080±0.010, and 0.010±0.001 (F=2434.610, P= 0.000), and STAT-5 protein expression was also significantly inhibited. The expression of STAT-5 protein in U937 cells after treated with different concentrations of JQ1 (0.2, 1.0 and 4.0 μmol/L) for 48 h were 0.71± 0.19, 0.62±0.16, 0.53±0.14, and 1.00±0.21 in the control group (F= 263.135, P= 0.000). Conclusion JQ1 can effectively inhibit the proliferation of the acute myeloid leukemia cell line U937 cells and induce their apoptosis, and the possible mechanism of action is regulated via STAT-5 signaling pathway.

Epigenetic Modifications: Novel Therapeutic Approach for Thyroid Cancer

The incidence of thyroid cancer is growing the fastest among all cancers in the United States, especially in women. The number of patients with thyroid neoplasm is part of an even larger number of patients who often need to undergo an operation to exclude a cancer diagnosis. While differentiated thyroid cancer (papillary thyroid cancer and follicular thyroid cancer) accounts for most cases of thyroid cancer and has a relatively good prognosis, effective treatments for patients with de-differentiated and anaplastic thyroid cancer are still gravely needed. Despite progress in the identification of genetic changes in thyroid cancer, the impact of aberrant epigenetic alterations on thyroid cancer remains to be fully elucidated. Understanding of the roles of epigenetic changes in thyroid cancer could open new opportunities for the identification of innovative molecular targets for novel treatment modalities, especially for anaplastic thyroid cancer for which treatment is very limited. This article briefly reviews the studies that exemplify the potential for and promise of using epigenetic regulators in the treatment of thyroid cancer.

Effects of bromodomain containing protein 4 specific inhibitor JQ-1 on human hypertropic scar / 上海交通大学学报（医学版）

Objective·To investigate effect and the possible molecular mechanism of JQ1,a specific inhibitor of bromodomain containing protein 4,on human hypertropic scar.Methods·Primary fibroblasts were isolated from human hypertrophic scars and treated with JQ-1 of different concentrations (0.1,0.5,1.0,2.0,2.5,and 12.5μmol/L) for 48 h.Then CCK-8 kit and wound healing assay were used to measure proliferation and migration of the fibroblasts.ELISA was adopted to detect the levels of collagen type Ⅰ (COL Ⅰ) and TGF-β1 after JQ-1 treatment for 24 h.Thirty-six nude mice were used for hypertrophic scar models.Human hypertrophic scars (1.0 cm× 1.0 cm×0.5 cm) were grafted subcutaneously at the backs of nude mice to establish scar animal models.After 4 weeks,the nude mice were averagely divided into two groups,i.e.JQ-1 group and DMSO group,which were respectively injected with 0.5 μmol/L JQ-1 and 0.1％ DMSO each mouse every day.COL Ⅰ / Ⅲ and α-smooth muscle actin (α-SMA) were examined by immunohistochemical method and sirius red staining.Results·Cell experiments showed that JQ-1 with the concentration of 0.5 μmol/L and above significantly inhibited proliferation of fibroblasts (P＜0.01).JQ-1 inhibited migration of fibroblast (P＜0.01).JQ-1 inhibited secretion of COL Ⅰ and TGF-β1 of fibroblasts (P＜0.01).Animal experiments showed that concentration and proportion of COL Ⅰ / Ⅲ in JQ-1 group decreased compared to DMSO group (P＜0.05).α-SMA protein expression in JQ-1 group also decreased (P＜0.05).Conclusion·JQ-1 can inhibit proliferation,migration,secretion of COL Ⅰ,and production of TGF-β1 of human sear fibroblasts in vitro;it can also inhibit secretion of COL Ⅰ /Ⅲ and fibroblast-myofibroblast differentiation in the human hypertrophic scars in nude mice.

BET Bromodomain Involves in Inflammatory Genes Transcription via Regulation of NF-κB Signaling Pathway / 现代生物医学进展

Objective:To explore bromodomain and extra-terminal (BET) inhibition in the regulation of vascular endothelial cells activation and early atherosclerosis formation and its potential molecular mechanisms.Methods:1.Human umbilical vein endothelial cells (HUVEC) and mouse heart endothelial cells (MHEC) were isolated,and tumor necrosis factor α (TNFα) was used to activate in flammatory genes transcription in the presence or absence of JQ1,a specific BET inhibitor.The groups are as follows:(1)Normal control group;(2) TNFα(25 ng/mL)group;(3) TNFα+JQ 1 group.The gene mRNA and protein expression of inflammatory cytokines were measured by both real-time PCR and flow cytometry (FCM).2.LDL receptor-deficient (LDLR-/-) mice were randomly divided into 2 groups:JQ1 group (n=8,JQlintraperitoneal,50 mg/kg,daily) and control group (n=8,DMSO,daily).After 8 weeks feeding with high cholesterol diet,vascular cell adhesion molecule-1 (VCAM-1) expression in aortic arch was measured by immunohistochemistry.The activity of nuclear factor kappa B (NF-κB) signaling was monitored by 5XκB luciferase reporter assay in HEK293.Results:TNFα dramatically induced the mRNA and protein expression of inflammatory genes and JQ 1 significantly downregulated the induction of them (E-selectin,P-selectin,VCAM-1,IL-8)(P＜0.01).Immunohistochemistry detection indicated that JQ1 significantly downregulated the expression of VCAM-1 in aortic arch induced by 8 weeks high cholesterol diet feeding comparing to control group.In addition,BET bromodomain inhibition downregulated TNFα upregulated NF-κB transcriptional activity (P＜0.01).Conclusions:Our study demonstrated that BET bromodomain was involved in NF-κB mediated inflammatory genes expression;inhibition of BET bromodomain suppressed vascular endothelial activation in vitro,and attenuated early atherogenesis in vivo.

Bromodomain4 inhibitor JQ1 inhibits the proliferation of Ph positive acute lymphocytic leukemia cells and its mechanism / 白血病·淋巴瘤

Objective To observe the effect of bromodomain4 (brd4) inhibitor JQ1 on proliferation inhibition and apoptosis of Ph positive acute lymphocytic leukemia (Ph+ ALL) cells, and to explore the influence on the expression of brd4 and its downstream genes (myc and p53), and the reverse effect on bcr-abl.Methods Different concentrations of JQ1 were used on SUP-B15 cells.The proliferation inhibition rate was detected by MTT, the apoptosis rate was determined by flow cytometry (FCM), and the expressions of bcr-abl mRNA, brd4 mRNA, myc mRNA and p53 mRNA were detected by real-time fluorescent quantitative PCR (RT-PCR).Results Different concentrations of JQ1 inhibited SUP-B15 cells proliferation and induced cell apoptosis.The apoptosis rate was significantly increased compared with that in control group with a time-dose dependent manner.Median inhibitory concentration at 72 h was 1.0 pmol/L.At the same time, JQ1 decreased the transcription levels of bcr-abl mRNA, brd4 mRNA and myc mRNA, and increased the transcription level of p53 mRNA.Conclusions As a brd4 inhibitor, JQ1 can decrease the expression of brd4 to affect the expression of its downstream genes myc and p53, meanwhile, it can change the over expression of bcr-abl to suppress the proliferation of Ph+ ALL cells and induce apoptosis.