KDM5D inhibits the transcriptional activation of FKBP4 by suppressing the expression of E2F1 in colorectal cancer in males.

Colorectal cancer (CRC) remains the most frequently diagnosed malignancy and also a major contributor to cancer-related death throughout the world. Here, we first revealed the role of histone lysine-specific demethylase 5D (KDM5D) in CRC in males. KDM5D expression in tumor and adjacent tissues of male CRC patients was investigated using immunohistochemistry and RT-qPCR, and the correlation between its expression and patients' prognosis was analyzed. Downregulation of KDM5D in CRC patients was associated with poor prognoses. Overexpression of KDM5D significantly inhibited the growth and metastasis of CRC in vitro and in vivo. The downstream mechanism of KDM5D in CRC was investigated using bioinformatics analysis, and the regulatory relationship was confirmed by ChIP-qPCR and luciferase reporter assays. KDM5D suppressed E2F1 expression by mediating H3K4me3 demethylation. E2F1, highly expressed in CRC, promoted the expression of FKBP4 at the transcriptional level by binding to the FKBP4 promoter. Finally, rescue experiments revealed that overexpression of FKBP4 significantly reversed the inhibitory effect of KDM5D on CRC growth and metastasis. Collectively, KDM5D exerted an anti-tumor and anti-metastatic in CRC through demethylation in E2F1 and suppression of FKBP4 transcription, which might represent a novel target in CRC treatment in male.

Targeting Bfl-1 via acute CDK9 inhibition overcomes intrinsic BH3-mimetic resistance in lymphomas.

BH3 mimetics like venetoclax target prosurvival Bcl-2 family proteins and are important therapeutics in the treatment of hematological malignancies. We demonstrate that endogenous Bfl-1 expression can render preclinical lymphoma tumor models insensitive to Mcl-1 and Bcl-2 inhibitors. However, suppression of Bfl-1 alone was insufficient to fully induce apoptosis in Bfl-1-expressing lymphomas, highlighting the need for targeting additional prosurvival proteins in this context. Importantly, we demonstrated that cyclin-dependent kinase 9 (CDK9) inhibitors rapidly downregulate both Bfl-1 and Mcl-1, inducing apoptosis in BH3-mimetic-resistant lymphoma cell lines in vitro and driving in vivo tumor regressions in diffuse large B-cell lymphoma patient-derived xenograft models expressing Bfl-1. These data underscore the need to clinically develop CDK9 inhibitors, like AZD4573, for the treatment of lymphomas using Bfl-1 as a selection biomarker.

AKR1C3 mediates pan-AR antagonist resistance in castration-resistant prostate cancer.

BACKGROUND: Antiandrogens are effective therapies that block androgen receptor (AR) transactivation and signaling in over 50% of castration-resistant prostate cancer (CRPC) patients. However, an estimated 30% of responders will develop resistance to these therapies within 2 years. JNJ-pan-AR is a broad-spectrum AR antagonist that inhibits wild-type AR as well as several mutated versions of AR that have emerged in patients on chronic antiandrogen treatment. In this work, we aimed to identify the potential underlying mechanisms of resistance that may result from chronic JNJ-pan-AR treatment. METHODS: The LNCaP JNJR prostate cancer subline was developed by chronically exposing LNCaP parental cells to JNJ-pan-AR. Transcriptomic and proteomic profiling was performed to identify potential drivers and/or biomarkers of the resistant phenotype. RESULTS: Several enzymes critical to intratumoral androgen biosynthesis, Aldo-keto reductase family 1 member C3 (AKR1C3), UGT2B15, and UGT2B17 were identified as potential upstream regulators of the JNJ-pan-AR resistant cells. While we confirmed the overexpression of all three enzymes in the resistant cells only AKR1C3 expression played a functional role in driving JNJ-pan-AR resistance. We also discovered that AKR1C3 regulates UGT2B15 and UGT2B17 expression in JNJ-pan-AR resistant cells. CONCLUSIONS: This study supports the rationale to further investigate the benefits of AKR1C3 inhibition in combination with antiandrogens to prevent CRPC disease progression.

Brain astrocytes and microglia express functional MR1 molecules that present microbial antigens to mucosal-associated invariant T (MAIT) cells.

It is unknown whether brain astrocytes and microglia have the capacity to present microbial antigens via the innate immune MR1/MAIT cell axis. We have detected MAIT cells in the normal mouse brain and found that both astrocytes and microglia are MR1+. When we stimulated brain astrocytes and microglia with E. coli, and then co-cultured them with MAIT cells, MR1 surface expression was upregulated and MAIT cells were activated in an antigen-dependent manner. Considering the association of MAIT cells with inflammatory conditions, including those in the CNS, the MR1/MAIT cell axis could be a novel therapeutic target in neuroinflammatory disorders.

LncRNA HORAS5 promotes taxane resistance in castration-resistant prostate cancer via a BCL2A1-dependent mechanism.

Background: Castration-resistant prostate cancer (CRPC) is an incurable malignancy. Long noncoding RNAs (lncRNAs) play key roles in drug resistance. Materials & methods: LncRNA HORAS5 role in cabazitaxel resistance (i.e., cell-count, IC50 and caspase activity) was studied via lentiviral-mediated overexpression and siRNA-based knockdown. Genes expression was analyzed with RNA-sequencing, reverse transcription quantitative PCR (RT-qPCR) and western blot. HORAS5 expression was queried in clinical database. Results: Cabazitaxel increased HORAS5 expression that upregulated BCL2A1, thereby protecting CRPC cells from cabazitaxel-induced apoptosis. BCL2A1 knockdown decreased cell-count and increased apoptosis in CRPC cells. HORAS5-targeting antisense oligonucleotide decreased cabazitaxel IC50. In CRPC clinical samples, HORAS5 expression increased upon taxane treatment. Conclusion:HORAS5 stimulates the expression of BCL2A1 thereby decreasing apoptosis and enhancing cabazitaxel resistance in CRPC cells.

APOBEC3B interaction with PRC2 modulates microenvironment to promote HCC progression.

OBJECTIVE: APOBEC3B (A3B), a cytidine deaminase acting as a contributor to the APOBEC mutation pattern in many kinds of tumours, is upregulated in patients with hepatocellular carcinoma (HCC). However, APOBEC mutation patterns are absent in HCC. The mechanism of how A3B affects HCC progression remains elusive. DESIGN: A3B -promoter luciferase reporter and other techniques were applied to elucidate mechanisms of A3B upregulation in HCC. A3B overexpression and knockdown cell models, immunocompetent and immune-deficient mouse HCC model were conducted to investigate the influence of A3B on HCC progression. RNA-seq, flow cytometry and other techniques were conducted to analyse how A3B modulated the cytokine to enhance the recruitment of myeloid--derived suppressor cells (MDSCs) and tumour--associated macrophages (TAMs). RESULTS: A3B upregulation through non-classical nuclear factor-κB (NF-κB)signalling promotes HCC growth in immunocompetent mice, associated with an increase of MDSCs, TAMs and programmed cell death1 (PD1) exprssed CD8+ T cells. A CCR2 antagonist suppressed TAMs and MDSCs infiltration and delayed tumour growth in A3B and A3BE68Q/E255Q- expressing mouse tumours. Mechanistically, A3B upregulation in HCC depresses global H3K27me3 abundance via interaction with polycomb repressor complex 2 (PRC2) and reduces an occupancy of H3K27me3 on promoters of the chemokine CCL2 to recruit massive TAMs and MDSCs. CONCLUSION: Our observations uncover a deaminase-independent role of the A3B in modulating the HCC microenvironment and demonstrate a proof for the concept of targeting A3B in HCC immunotherapy.

Increased expression of the immunosuppressive interleukin-35 in patients with non-small cell lung cancer.

BACKGROUND: The immunosuppressive role of the cytokine IL-35 in patients with non-small cell lung cancer (NSCLC) is poorly understood. In this study, we analysed the localisation and regulation of IL-35 in the lung of patients with non-small cell lung cancer (NSCLC) to further elucidate the immune-escape of cancer cells in perioperative course of disease. METHODS: Interleukin 35 (IL-35) was measured by ELISA in postoperative serum from 7 patients with NSCLC as well as 8 samples from healthy controls. Immunohistochemistry, FACS analysis, real-time PCR, as well as western blot from samples of the control (CTR), peri-tumoural (PT) and the tumoural (TU) region of the lung derived from patients with NSCLC and 10 controls were performed. RESULTS: Here we found elevated levels of IL-35 in the TU region as well as postoperative serum from patients with lung adenocarcinoma. Consistently, we found an increased expression of IL-35+Foxp-3+ cells, which associated with ARG1 mRNA expression and decreased TNFA in the TU region of the lung of patients with NSCLC as compared to their CTR region. Furthermore, in the CTR region of the lung of patients with NSCLC, CD68+ macrophages were induced and correlated with IL-35+ cells. Finally, IL-35 positively correlated with TTF-1+PD-L1+ cells in the TU region of NSCLC patients. CONCLUSIONS: Induced IL-35+Foxp3+ cell numbers in the TU region of the lung of patients with NSCLC associated with ARG1 mRNA expression and with TTF-1+PD-L1+ cells. In the tumour-free CTR area, IL-35 correlated with CD68+ macrophages. Thus inhibitors to IL-35 would probably succeed in combination with antibodies against immune checkpoints like PD-L1 and PD-1 currently used against NSCLC because they would inhibit immunosuppressive macrophages and T regulatory cells while promoting T cell-mediated anti-tumoural immune responses in the microenvironment as well as the TU region of NSCLC patients.

Interleukin-35 Promotes Macrophage Survival and Improves Wound Healing After Myocardial Infarction in Mice.

RATIONALE: Targeting inflammation has been shown to provide clinical benefit in the field of cardiovascular diseases. Although manipulating regulatory T-cell function is an important goal of immunotherapy, the molecules that mediate their suppressive activity remain largely unknown. IL (interleukin)-35, an immunosuppressive cytokine mainly produced by regulatory T cells, is a novel member of the IL-12 family and is composed of an EBI3 (Epstein-Barr virus-induced gene 3) subunit and a p35 subunit. However, the role of IL-35 in infarct healing remains elusive. OBJECTIVE: This study aimed to determine whether IL-35 signaling is involved in healing and cardiac remodeling after myocardial infarction (MI) and, if so, to elucidate the underlying molecular mechanisms. METHODS AND RESULTS: IL-35 subunits (EBI3 and p35), which are mainly expressed in regulatory T cells, were upregulated in mice after MI. After IL-35 inhibition, mice showed impaired infarct healing and aggravated cardiac remodeling, as demonstrated by a significant increase in mortality because of cardiac rupture, decreased wall thickness, and worse cardiac function compared with wild-type MI mice. IL-35 inhibition also led to decreased expression of α-SMA (α-smooth muscle actin) and collagen I/III in the hearts of mice after MI. Pharmacological inhibition of IL-35 suppressed the accumulation of Ly6Clow and major histocompatibility complex IIlow/C-C motif chemokine receptor type 2- (MHC IIlow CCR2-) macrophages in infarcted hearts. IL-35 activated transcription of CX3CR1 (C-X3-C motif chemokine receptor 1) and TGF (transforming growth factor) ß1 in macrophages by inducing GP130 signaling, via IL12Rß2 and phosphorylation of STAT1 (signal transducer and activator of transcription family) and STAT4 and subsequently promoted Ly6Clow macrophage survival and extracellular matrix deposition. Moreover, compared with control MI mice, IL-35-treated MI mice showed increased expression of α-SMA and collagen within scars, correlating with decreased left ventricular rupture rates. CONCLUSIONS: IL-35 reduces cardiac rupture, improves wound healing, and attenuates cardiac remodeling after MI by promoting reparative CX3CR1+Ly6Clow macrophage survival.

Polyomavirus T Antigen Induces APOBEC3B Expression Using an LXCXE-Dependent and TP53-Independent Mechanism.

APOBEC3B is a single-stranded DNA cytosine deaminase with beneficial innate antiviral functions. However, misregulated APOBEC3B can also be detrimental by inflicting APOBEC signature C-to-T and C-to-G mutations in genomic DNA of multiple cancer types. Polyomavirus and papillomavirus oncoproteins induce APOBEC3B overexpression, perhaps to their own benefit, but little is known about the cellular mechanisms hijacked by these viruses to do so. Here we investigate the molecular mechanism of APOBEC3B upregulation by the polyomavirus large T antigen. First, we demonstrate that the upregulated APOBEC3B enzyme is strongly nuclear and partially localized to virus replication centers. Second, truncated T antigen (truncT) is sufficient for APOBEC3B upregulation, and the RB-interacting motif (LXCXE), but not the p53-binding domain, is required. Third, genetic knockdown of RB1 alone or in combination with RBL1 and/or RBL2 is insufficient to suppress truncT-mediated induction of APOBEC3B Fourth, CDK4/6 inhibition by palbociclib is also insufficient to suppress truncT-mediated induction of APOBEC3B Last, global gene expression analyses in a wide range of human cancers show significant associations between expression of APOBEC3B and other genes known to be regulated by the RB/E2F axis. These experiments combine to implicate the RB/E2F axis in promoting APOBEC3B transcription, yet they also suggest that the polyomavirus RB-binding motif has at least one additional function in addition to RB inactivation for triggering APOBEC3B upregulation in virus-infected cells.IMPORTANCE The APOBEC3B DNA cytosine deaminase is overexpressed in many different cancers and correlates with elevated frequencies of C-to-T and C-to-G mutations in 5'-TC motifs, oncogene activation, acquired drug resistance, and poor clinical outcomes. The mechanisms responsible for APOBEC3B overexpression are not fully understood. Here, we show that the polyomavirus truncated T antigen (truncT) triggers APOBEC3B overexpression through its RB-interacting motif, LXCXE, which in turn likely modulates the binding of E2F family transcription factors to promote APOBEC3B expression. This work strengthens the mechanistic linkage between active cell cycling, APOBEC3B overexpression, and cancer mutagenesis. Although this mutational mechanism damages cellular genomes, viruses may leverage it to promote evolution, immune escape, and pathogenesis. The cellular portion of the mechanism may also be relevant to nonviral cancers, where genetic mechanisms often activate the RB/E2F axis and APOBEC3B mutagenesis contributes to tumor evolution.

The nuclear receptor Shp regulates morphine withdrawal syndrome via modulation of Ugt2b expression in mice.

In this study, we aimed to investigate a potential role of small heterodimer partner (Shp, a nuclear receptor) in regulation of morphine withdrawal syndrome and to determine the mechanisms thereof. Somatic opiate withdrawal and pharmacokinetic experiments were performed with wild-type (WT) and Shp knockout (Shp-KO) mice. Regulatory effects of Shp on Ugt2b expression were assessed in vitro (using mouse hepatoma Hepa1-6 cells) and in vivo (using Shp-KO mice). Ugt2b mRNA and protein expressions were determined by qPCR and Western blotting, respectively. Microsomal Ugt2b activity was measured with morphine and chloramphenicol. Luciferase reporter, promoter analysis and chromatin immunoprecipitation assays were performed to identify the Hnf1α- and Rev-erbα-binding sites in Ugt2b36 promoter. Protein-protein interactions were explored using co-immunoprecipitation assays. Shp ablation exacerbated morphine withdrawal syndrome in mice. Furthermore, systemic and liver exposures of morphine were elevated in Shp-KO mice due to reduced metabolism. Down-regulation of morphine metabolism was supported by down-regulated expressions of Ugt2b genes in Shp-KO mice. Regulation of Ugt2b genes by Shp was confirmed in mouse hepatoma Hepa1-6 cells. Moreover, Shp positively regulated Ugt2b36 expression through repression of Dec2 and Rev-erbα, two negative regulators of Ugt2b36 enzyme. Rev-erbα repressed Ugt2b36 transcription via direct binding to a specific response element (located at -30/-15 bp) in promoter region of Ugt2b36, whereas Dec2 acted on Ugt2b36 expression via suppression of Hnf1α-transactivation of Ugt2b36 gene. In conclusion, Shp regulated morphine withdrawal syndrome via modulation of Ugt2b expression and detoxification capacity. Targeting Shp may represent a novel approach for management of morphine dependence.

APOBEC3B protein expression and mRNA analyses in patients with high-grade serous ovarian carcinoma.

APOBEC3 enzymes are part of the innate immune system and they are important in retroviral defense. The number of mutations in ovarian cancer increases with rising levels of APOBEC3B mRNA. We could confirm that APOBEC3B mRNA is upregulated in ovarian cancer cell lines and in ovarian cancer tissue. We evaluated APOBEC3B expression in histologically defined subtypes of ovarian cancer to identify its influence on overall survival (OS) and progression-free survival (PFS). Tissue microarrays from 219 patients with high-grade serous (HGSC), 61 with low-grade serous (LGSC), 62 with endometrioid (EC) and 55 with clear cell (CCC) ovarian carcinoma were stained using an antibody against APOBEC3B. Real-time quantitative PCR was performed to detect APOBEC3B mRNA levels in 274 cases of HGSC, in 11 cases of LGSC, in 47 cases of EC and in 29 cases of CCC. Tumor-infiltrating lymphocytes (TILs) have been evaluated in a previous project. APOBEC3B staining was cytoplasmic as well as nuclear and both were positively correlated (P<0.001). In HGSC a trend was detectable for positive cytoplasmic staining as favorable regarding OS (P=0.283) and PFS (P=0.137). High levels of APOBEC3B mRNA were associated with prolonged PFS in HGSC in univariate analyses (P=0.043) and multivariate analyses (HR 0.55; 95%CI 0.35-0.88; P=0.012). APOBEC3B cytoplasmic staining and APOBEC3B mRNA were positively correlated with TILs. APOBEC3B in HGSC is related to an active immune infiltrate. However, there is no evidence for APOBEC3B as a clinically relevant prognostic biomarker.

Expression of glutamine metabolism-related proteins in Hürthle cell neoplasm of thyroid: Comparison with follicular neoplasm.

PURPOSE: We evaluated the expression of glutaminolysis-related proteins in Hurthle cell neoplasms (HCN) and follicular neoplasms (FN) of the thyroid, and investigated its clinical implication. METHODS: Tissue microarrays were constructed from 264 FNs (112 follicular carcinomas [FCs] and 152 follicular adenomas [FAs]) and 108 HCNs (27 Hurthle cell carcinomas [HCCs] and 81 Hurthle cell adenomas [HCAs]. The immunohistochemical staining result of 3 glutaminolysis-related proteins (Glutaminase 1 [GLS1], glutaminate dehydrogenase [GDH] and alanine- serine, cysteine-preferring transporter 2 [ASCT2]) was analyzed. RESULTS: GLS1 and GDH showed significantly higher expression rates in HCN compared to FN (P<0.001). More HCN cases showed co-positivity of multiple glutaminolysis-related proteins than those of FN cases (P<0.001). In silico analysis, both GLUD1 and GLUD2 showed higher expression rate in HCA compared to FA (P=0.027 and P=0.018, respectively). SLC1A5 expression was highest in HCA, followed by FC and FA (HCA vs FC, P=0.023; FC vs FA, P=0.002). CONCLUSION: FN and HCN exhibit a different expression pattern for glutaminolysis-related proteins, and GLS1 and GDH have higher expression rates in HCN and FN.

Methylenetetrahydrofolate Dehydrogenase 1 (MTHFD1) is Underexpressed in Clear Cell Renal Cell Carcinoma Tissue and Transfection and Overexpression in Caki-1 Cells Inhibits Cell Proliferation and Increases Apoptosis.

BACKGROUND The aims of this study were to investigate the expression of methylenetetrahydrofolate dehydrogenase 1 (MTHFD1) in human tissue containing clear cell renal cell carcinoma (CCRCC) compared with normal renal tissue, and the effects of upregulating the expression of MTHFD1 in the human CCRCC cell line, Caki-1. MATERIAL AND METHODS Tumor and adjacent normal renal tissue were obtained from 44 patients who underwent radical nephrectomy for CCRCC. Caki-1 human CCRCC cells were divided into the control group, the empty vector (EV) group, and the plasmid-treated group that overexpressed MTHFD1. MTHFD1 mRNA and protein levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot, respectively. The cell counting kit-8 (CCK-8) assay measured cell viability. Flow cytometry evaluated apoptosis and the cell cycle. Western blot measured the protein levels of MTHFD1, Bax, Bcl-2, Akt, p53, and cyclin D1, and qRT-PCR determined the gene expression profiles. RESULTS MTHFD1 mRNA and protein levels in CCRCC tumor tissues were significantly lower compared with adjacent normal renal tissue. MTHFD1 over-expression in Caki-1 cells inhibited cell proliferation, arrested cells in the G1 phase, increased cell apoptosis, and upregulated gene and protein expression of Bax/Bcl-2 and p53 and inhibited p-Akt, and cyclin D1. CONCLUSIONS MTHFD1 was underexpressed in CCRCC tissue when compared with normal renal tissue. MTHFD1 transfection of human CCRCC Caki-1 cells in vitro inhibited cell proliferation and promoted apoptosis, associated with reduced expression of cyclin D1, reduced Akt phosphorylation, and increased expression of Bax/Bcl-2 and p53.

Methylenetetrahydrofolate Dehydrogenase 1 Silencing Expedites the Apoptosis of Non-Small Cell Lung Cancer Cells via Modulating DNA Methylation.

BACKGROUND Non-small cell lung cancer (NSCLC) accounts for about 85% of all types of lung cancer. Methylenetetrahydrofolate dehydrogenase 1 (MTHFD1) is involved in DNA methylation, and DNA methylation is related to tumorigenesis. The role of MTHFD1 in NSCLC was examined in our study. MATERIAL AND METHODS The correlation between the expression of MTHFD1 and the clinicopathological features of patients diagnosed with lung cancer was investigated using the chi-square test. The viability and apoptosis of NCI-H1299 cells was respectively detected using cell counting kit-8 and flow cytometry assays. The expression levels of MTHFD1, apoptosis-related factors and DNA methyltransferase-related factors were assessed by quantitative real-time PCR (qRT-PCR) and western blot assays. RESULTS We found that MTHFD1 expression in the tumor tissues and cells was higher than that of adjacent normal tissues and cells. The survival time of patients with high MTHFD1 expression was shorter than those with low MTHFD1 expression. The expression level of MTHFD1 was related to tumor size, TNM stage, histologic grade, and metastasis, but not linked to gender and age. Besides, si-MTHFD1 significantly decreased the viability of cells in a time-dependent manner, and increased cell apoptosis. When cells were transfected with MTHFD1-siRNA, the levels of surviving and B-cell lymphoma-2 (Bcl-2) were attenuated, while p53 and Bcl-2 associated X protein (Bax) levels were enhanced. Moreover, si-MTHFD1 markedly downregulated the expression levels of DNA methyltransferase 1 (DNMT1), DNMT3a, and DNMT3b. CONCLUSIONS Collectively, our results proved that MTHFD1 silencing obviously reduced the proliferation and enhanced the apoptosis of NSCLC via suppressing DNA methylation.

Skeletal muscle amino acid transporter and BCAT2 expression prior to and following interval running or resistance exercise in mode-specific trained males.

Endurance (END)- and resistance (RES)-trained males performed interval running or resistance exercise during three consecutive days (bouts 1-3). Muscle biopsies were obtained at baseline, 2 h post-bout 1, and 72 h post-bout 3. Amino acid transporter SNAT2 mRNA was 75% greater in END (group p = 0.008), and increased ~ 70% 2 h post in both groups (time p = 0.023). Amino acid transporter PAT1 mRNA was 2.7-fold greater in RES (group p = 0.002). Baseline protein levels of the mitochondrial aminotransferase BCAT2 were 79% greater in END (p = 0.015).

Overexpression of SLC1a5 in lymph node metastases outperforms assessment in the primary as a negative prognosticator in non-small cell lung cancer.

Despite recent advances in therapeutic options, lung cancer is the leading cause of death among malignant diseases worldwide. Glutamine-dependence is an established attribute in cancer tissue with emerging importance as a diagnostic and therapeutic target. We analysed the expression of SLC1a5, a major glutamine transporter, in the primary tumour and corresponding nodal metastasis of non-small cell lung cancer (NSCLC) to investigate its biological impact. Expression of SLC1a5 was analysed by immunohistochemistry in 259 NSCLC and in 142 nodal metastases and correlated with clinicopathological parameters including overall survival. SLC1a5 expression in the primary tumour and in the corresponding lymph node metastasis revealed a positive correlation (p = 0.005). Moreover, overexpression of SLC1a5 was found to be an independent prognostic factor (p = 0.027) if assessed in lymph node metastases only. SLC1A5 expression was studied for the first time in both primary NSCLC and its corresponding nodal metastasis. Our results indicate that overexpression of SLC1a5 is associated with shorter overall survival. This proved to be an independent prognosticator if assessed in the lymph node metastases. Thus, diagnostics in lymph node metastasis provide superior prognostic information for SLC1a5 overexpression and may open target prediction for future therapeutic options.

Suppression of interferon-mediated anti-HBV response by single CpG methylation in the 5'-UTR of TRIM22.

OBJECTIVE: Interferons (IFNs) mediate direct antiviral activity. They play a crucial role in the early host immune response against viral infections. However, IFN therapy for HBV infection is less effective than for other viral infections. DESIGN: We explored the cellular targets of HBV in response to IFNs using proteome-wide screening. RESULTS: Using LC-MS/MS, we identified proteins downregulated and upregulated by IFN treatment in HBV X protein (HBx)-stable and control cells. We found several IFN-stimulated genes downregulated by HBx, including TRIM22, which is known as an antiretroviral protein. We demonstrated that HBx suppresses the transcription of TRIM22 through a single CpG methylation in its 5'-UTR, which further reduces the IFN regulatory factor-1 binding affinity, thereby suppressing the IFN-stimulated induction of TRIM22. CONCLUSIONS: We verified our findings using a mouse model, primary human hepatocytes and human liver tissues. Our data elucidate a mechanism by which HBV evades the host innate immune system.

Cutting Edge: Low-Affinity TCRs Support Regulatory T Cell Function in Autoimmunity.

Regulatory T cells (Tregs) use a distinct TCR repertoire and are more self-reactive compared with conventional T cells. However, the extent to which TCR affinity regulates the function of self-reactive Tregs is largely unknown. In this study, we used a two-TCR model to assess the role of TCR affinity in Treg function during autoimmunity. We observed that high- and low-affinity Tregs were recruited to the pancreas and contributed to protection from autoimmune diabetes. Interestingly, high-affinity cells preferentially upregulated the TCR-dependent Treg functional mediators IL-10, TIGIT, GITR, and CTLA4, whereas low-affinity cells displayed increased transcripts for Areg and Ebi3, suggesting distinct functional profiles. The results of this study suggest mechanistically distinct and potentially nonredundant roles for high- and low-affinity Tregs in controlling autoimmunity.

Correlation Between NKG2DL Expression and Antitumor Effect of Protein-bound Polysaccharide-K in Tumor-bearing Mouse Models.

BACKGROUND/AIM: We investigated the relationship between the expression of natural killer group 2, member D ligands (NKG2DLs) and the antitumor effects of protein-bound polysaccharide-K (PSK). MATERIALS AND METHODS: PSK was administered to evaluate its effectiveness against tumor growth. The expression of Rae-1 and H60 were analyzed in multiple cell lines. RESULTS: PSK showed the highest antitumor effects in mice implanted with cells expressing neither Rae-1 nor H60. PSK had little antitumor effect in mice implanted with cells expressing both Rae-1 and H60. A correlation between the expression of NKG2DLs and the antitumor effect of PSK was observed. After PSK administration, INF-γ production in CD8+ T cells increased in mice with cells expressing neither Rae-1 nor H60, but did not change in mice implanted with cells expressing both Rae-1 and H60. CONCLUSION: We demonstrated that the expression of NKG2DLs affects tumor immunity and the efficacy of immuno therapy in tumor-bearing mouse model.

Exemestane and Its Active Metabolite 17-Hydroexemestane Induce UDP-Glucuronosyltransferase (UGT) 2B17 Expression in Breast Cancer Cells.

Exemestane (EXE) is an aromatase inhibitor indicated for endocrine therapy of breast cancer in postmenopausal women. The primary active metabolite of EXE, 17-hydroexemestane (17-HE), is inactivated via glucuronidation, mainly by UDP-glucuronosyltransferase 2B17 (UGT2B17). UGT2B17 also has a primary role in inactivation of endogenous androgens testosterone and dihydrotestosterone and may play an important role in regulation of breast and prostate tumor intracrinology. We recently reported that UGT2B17 could be induced by both estrogenic and androgenic ligands in breast cancer cells via binding of the estrogen receptor α (ERα) or the androgen receptor (AR) to a complex regulatory unit in the proximal UGT2B17 promoter. In this study we show that both EXE and 17-HE increase UGT2B17 mRNA levels in breast cancer MCF-7 and MDA-MB-453 cells, and increase glucuronidation of UGT2B17 substrates, including 17-HE and androsterone. Using antagonists of ERα and AR as well as inhibition mediated by small interfering RNA (siRNA) we demonstrate that EXE and 17-HE induce UGT2B17 expression primarily via the AR. This result is consistent with previous reports that 17-HE can act as an AR ligand. In vitro studies suggest that multiple steroid-responsive DNA elements within the proximal promoter are involved in the response to 17-HE-liganded AR. The up-regulation of UGT2B17 by EXE and 17-HE in breast cancer cells might enhance the local metabolism of 17-HE as well as that of endogenous androgens, hence impacting potentially on treatment outcomes.