Controllable Regioselective [3+2] Cyclizations of N-CF3 Imidoyl Chlorides and Ph3PNNC: Divergent Synthesis of N-CF3 Triazoles.

Presented herein are two distinct regiodivergent [3+2] cyclization reactions between N-CF3 imidoyl chlorides and N-isocyaniminotriphenylphosphorane (NIITP) that include flexible modulation of the electronic properties of NIITP. The regioselectivity of reactions was different in the absence and presence of the Mo catalyst. The approach provides alternative efficient and scalable routes for N-CF3 triazole synthesis, demonstrating a broad substrate scope, excellent functional group tolerance, and practical advantages.

N-CF3 Imidoyl Chlorides: Scalable N-CF3 Nitrilium Precursors for the Construction of N-CF3 Compounds.

A wide range of N-CF3 imidoyl chlorides were synthesized for the first time via the N-trifluoromethylation of nitriles in DCM by using AlCl3-activated PhICF3Cl as the CF3 source. The reactions of them with N-/O-/S-nucleophiles, as well as with 1,3-dipoles, were carried out to efficiently deliver N-CF3 amidines/imidates/thioimidates and N-CF3 azoles, demonstrating that they are a class of scalable NCF3-containing synthons in the synthesis of N-CF3 compounds.

Blockage of TIM-3 relieves lupus nephritis by expanding Treg cells and promoting their suppressive capacity in MRL/lpr mice.

T Cell Immunoglobulin and Mucin Containing Protein-3 (TIM-3) is an important immune checkpoint protein that is expressed in Tregs and affects their function. However, the expression and role of TIM-3 in modulating regulatory T cells (Tregs) in lupus nephritis (LN) are still unknown. In this study, we found that the percentage of TIM-3+ cells among spleen lymphocytes, CD4+ T cells and Tregs was higher in MRL/lpr mice than in MpJ mice. TIM-3high CD4+ T cells and TIM-3high Tregs were mainly responsible for the increase. The percentage of Tregs in TIM-3high CD4+ T cells was lower than that in TIM-3low CD4+ T cells, and the expression of CTLA-4 and IL-10 was lower in TIM-3high Tregs than in the TIM-3low Tregs in MRL/lpr mice. Blockade of TIM-3 in vivo significantly increased the Treg population and the expression of CTLA-4 and IL-10 in Tregs, thus relieving the LN symptoms and pathology in MRL/lpr mice. Additionally, bioinformatics analysis indicated that TIM-3 regulates Treg cells in LN mainly through cytokine-cytokine receptor interactions, the PI3K-Akt signaling pathway, the T cell receptor signaling pathway, Th17 cell differentiation and the FoxO signaling pathway. Together, our study has demonstrated that TIM-3 regulates Tregs in LN and that overexpression of TIM-3 in CD4+ T cells and Tregs leads to Treg quantity and quality deficiency in MRL/lpr mice. Blockade of TIM-3 protects against LN by expanding Tregs and enhancing their suppressive capacity. Finally, TIM-3 might be a potential therapeutic target for the treatment of LN.

Rapamycin relieves lupus nephritis by regulating TIM-3 and CD4+CD25+Foxp3+ Treg cells in an MRL/lpr mouse model.

Lupus nephritis (LN) is a severe consequence of systemic lupus erythematosus (SLE) and is an important driver of morbidity and mortality in SLE. Treg cells and TIM-3 play an important role in the pathogenesis of LN. The beneficial effect of rapamycin on LN has been confirmed in both mouse models and patients, but the effect of rapamycin on Treg cells and TIM-3 is not yet completely understood. In this study, rapamycin treatment attenuated proteinuria, histological damage, and renal deposition of C3, and improved renal function. Spleen and renal draining lymph node weight and serum levels of anti-dsDNA antibodies were also improved by rapamycin. Furthermore, the frequency of Treg cells and Treg functional molecules, such as cytotoxic T cell antigen 4 (CTLA-4), interleukin 10 (IL-10), and transforming growth factor ß1 (TGF-ß1), increased significantly after treatment with rapamycin in MRL/lpr mice. We also found that expression of TIM-3 was significantly decreased in CD4+ T cells and Treg cells in mice treated with rapamycin. In summary, the study demonstrated that rapamycin treatment induced preferential expansion of CD4+CD25+Foxp3+ Tregs with increased expression of CTLA-4, IL-10, and TGF-ß1, and decreased TIM-3 expression, thereby ameliorating lupus nephritis in the MRL/lpr mouse model.

Bone marrow inhibition induced by azathioprine in a patient without mutation in the thiopurine S-methyltransferase pathogenic site: A case report.

BACKGROUND: Azathioprine (AZA) and its close analog 6-mercaptopurine are thiopurines widely used in the treatment of patients with cancer, organ transplantation, and autoimmune or inflammatory diseases, including systemic lupus erythematosus. Bone marrow inhibition is a common side effect of AZA, and severe bone marrow inhibition is related to decreased thiopurine S-methyltransferase (TPMT) activity. CASE SUMMARY: We herein report a patient with proliferative lupus nephritis who was using AZA for maintenance therapy, had no common TPMT pathogenic site mutations, and exhibited severe bone marrow inhibition on the 15th day after oral administration. CONCLUSION: This report alerts physicians to the fact that even though the TPMT gene has no common pathogenic site mutation, severe myelosuppression may also occur.

Bu Shen Yi Sui Capsule Alleviates Neuroinflammation and Demyelination by Promoting Microglia toward M2 Polarization, Which Correlates with Changes in miR-124 and miR-155 in Experimental Autoimmune Encephalomyelitis.

BACKGROUND: Bu Shen Yi Sui capsule (BSYS) is a traditional Chinese medicine prescription that has shown antineuroinflammatory and neuroprotective effects in treating multiple sclerosis (MS) and its animal model of experimental autoimmune encephalomyelitis (EAE). Microglia play an important role in neuroinflammation. The M1 phenotype of microglia is involved in the proinflammatory process of the disease, while the M2 phenotype plays an anti-inflammatory role. Promoting the polarization of microglia to M2 in MS/EAE is a promising therapeutic strategy. This study is aimed at exploring the effects of BSYS on microglial polarization in mice with EAE. METHODS: The EAE model was established by the intraperitoneal injection of pertussis toxin and subcutaneous injection of myelin oligodendrocyte glycoprotein (MOG)35-55 in C57BL/6J mice. The mice were treated with BSYS (3.02 g/kg), FTY720 (0.3 mg/kg), or distilled water by intragastric administration. H&E and LFB staining, transmission electron microscopy, qRT-PCR, immunofluorescence, ELISA, fluorescence in situ hybridization, and western blotting were used to detect the histological changes in myelin, microglial M1/M2 polarization markers, and the expression of key genes involved in EAE. Results and Conclusions. BSYS treatment of EAE mice increased the body weight, decreased the clinical score, and reduced demyelination induced by inflammatory infiltration. BSYS also inhibited the mRNA expression of M1 microglial markers while increasing the mRNA level of M2 markers. Additionally, BSYS led to a marked decrease in the ratio of M1 microglia (iNOS+/Iba1+) and an obvious increase in the number of M2 microglia (Arg1+/Iba1+). In the EAE mouse model, miR-124 expression was decreased, and miR-155 expression was increased, while BSYS treatment significantly reversed this effect and modulated the levels of C/EBP α, PU.1, and SOCS1 (target genes of miR-124 and miR-155). Therefore, the neuroprotective effect of BSYS against MS/EAE was related to promoting microglia toward M2 polarization, which may be correlated with changes in miR-124 and miR-155 in vivo.

miR-142 suppresses proliferation and induces apoptosis of osteosarcoma cells by upregulating Rb.

It has been reported that microRNA-142 (miR-142) is a tumor suppressor gene. The present study primarily investigated whether the overexpression of miR-142 was able to inhibit the proliferation, apoptosis and expression of apoptosis-associated proteins in osteosarcoma (OS) cells. Different concentrations of miR-142 were transfected into the OS MG-63 cell line using Lipofectamine 2000. The cell lines were divided into three groups: Normal group (non-transfected group), miR-142 transfected group, and negative group, which were transfected with random miR-142 fragment. The proliferation of cells was detected by MTT assay. The expression of miR-142 was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). DAPI staining was performed to investigate the influence of miR-142 on the morphology of MG-63c ells. The apoptotic cell percentages were determined by flow cytometry with Annexin V-fluorescein isothiocyanate/propidium iodide double staining. Expression of tumor suppressors, phosphatase and tensin homolog (PTEN) and Retinoblastoma-associated protein (Rb), and apoptosis-associated proteins were evaluated by western blotting. RT-qPCR indicated a higher expression of miR-142 in the transfected group (miR-142 was transfected into the MG-63 cell line) compared with that in the normal (non-transfected group) and negative control groups. The proliferation of miR-142 transfected cells was significantly lower compared with that in the normal and negative groups. Furthermore, an increased apoptosis rate accompanied by a statistically significant upregulation of PTEN, Rb phosphorylation, cleaved caspase-3 and cytochrome c protein levels were detected in the transfected group, indicating an internal apoptosis pathway was involved in this process. Furthermore, no significant changes were identified between the normal and negative groups (P>0.05). The present study demonstrated that miR-142 overexpression by liposomal transfection resulted in an inhibitory effect on MG-63 cell proliferation. The underlying mechanisms may relate to the upregulation of tumor suppressor and activation of caspase signaling pathway, which may provide a novel horizon in short nucleotide drugs on the management of OS.

Anticancer activity of stoppin based on a novel peptide delivery system.

Stoppin (L1) is a newly identified anticancer peptide, which is a potent p53­MDM2/MDMX inhibitor. Due to its limitation in cell delivery efficiency, a new peptide delivery system was developed based on a nucleic acid­polypeptide­liposome complex and its stability and effectiveness in vitro was investigated. The nucleic acid­stoppin­liposome complex was prepared and characterization of the complex was conducted. The stability of the complex was evaluated by enzyme digestion. Following transfection of the A549 cells with the complex, detection of green fluorescent protein (GFP) and luciferase activity was conducted to evaluate transfection efficiency. In addition, the anticancer activity of the complex was determined by 3­(4,5­dimethyl­thiazolyl­2)­2,5 diphenyltetrazolium bromide assay and apoptosis was detected by flow cytometry. The results indicated that the particle size of the complex was 102±10 nm and the encapsulation rate was ~100% when the ratio of liposome, L1 and plasmid was: 4 µl:1 µg:2 µg. The enzyme digestion experiment demonstrated that the complex was resistant to pancreatic and DNA enzyme degradation, indicating that the complex had biological stability. Cell transfection demonstrated that it had a mutual promotion effect on delivery, which could be confirmed by GFP fluorescence and luciferase assay. The cell­killing efficiency of this novel delivery system was three times higher than with stoppin alone at a low concentration. In conclusion, this novel stoppin peptide delivery system was stable. The nucleic acid­peptide­liposome complex can protect the internal component from the degradation of enzymes, promote entry of the peptide into the cells and enhance the anti­tumor activity of stoppin. Therefore, it is a promising approach for peptide delivery, which can be characterized and visualized using plasmids with GFP or luciferase.

Parthenolide inhibits cancer stem-like side population of nasopharyngeal carcinoma cells via suppression of the NF-κB/COX-2 pathway.

Cancer stem cells play a central role in the pathogenesis of nasopharyngeal carcinoma and contribute to both disease initiation and relapse. In this study, cyclooxygenase-2 (COX-2) was found to regulate cancer stem-like side population cells of nasopharyngeal carcinoma cells and enhance cancer stem-like cells' characteristics such as higher colony formation efficiency and overexpression of stemness-associated genes. The regulatory effect of COX-2 on cancer stem-like characteristics may be mediated by ABCG2. COX-2 overexpression by a gain-of-function experiment increased the proportion of side population cells and their cancer stemness properties. The present study also demonstrated that in contrast to the classical chemotherapy drug 5-fluorouracil, which increased the proportion of side population cells and upregulated the expression of COX-2, parthenolide, a naturally occurring small molecule, preferentially targeted the side population cells of nasopharyngeal carcinoma cells and downregulated COX-2. Moreover, we found that the cancer stem-like cells' phenotype was suppressed by using COX-2 inhibitors NS-398 and CAY10404 or knocking down COX-2 with siRNA and shRNA. These findings suggest that COX-2 inhibition is the mechanism by which parthenolide induces cell death in the cancer stem-like cells of nasopharyngeal carcinoma. In addition, parthenolide exhibited an inhibitory effect on nuclear factor-kappa B (NF-κB) nucler translocation by suppressing both the phosphorylation of IκB kinase complex and IκBα degradation. Taken together, these results suggest that parthenolide may exert its cancer stem cell-targeted chemotherapy through the NF-κB/COX-2 pathway.

Role of a novel functional variant in the PPP2R1A promoter on the regulation of PP2A-Aalpha and the risk of hepatocellular carcinoma.

Previously, we identified the genetic variant -241 (-/G) (rs11453459) in the PP2A-Aα gene (PPP2R1A) promoter and demonstrated that this variant influences the DNA-binding affinity of nuclear factor-kappa B (NF-κB). In this study, we further confirmed that the transcriptional activity of PPP2R1A may be regulated by NF-κB through the functional genetic variant -241 (-/G). Moreover, we also demonstrated that the methylation status of CpG islands in the promoter of PPP2R1A influences the activity of this gene promoter. Few studies have examined the role of this -241 (-/G) variant in genetic or epigenetic regulation in hepatocellular carcinoma (HCC). To investigate whether this functional variant in the PPP2R1A promoter is associated with the risk of HCC and confirm the function of the -241 (-/G) variant in the HCC population, we conducted a case-control study involving 251 HCC cases and 252 cancer-free controls from a Han population in southern China. Compared with the -241 (--) homozygote, the heterozygous -241 (-G) genotype (adjusted OR  = 0.32, 95% confidence interval (CI)  = 0.17-0.58, P<0.001) and the -241 (-G)/(GG) genotypes (adjusted OR  = 0.38, 95% CI  = 0.22-0.67, P  = 0.001) were both significantly associated with a reduced risk of HCC. Stratification analysis indicated that the protective role of -241 (-G) was more pronounced in individuals who were ≤ 40 years of age, female and HBV-negative. Our data suggest that the transcriptional activity of PPP2R1A is regulated by NF-κB through the -241 (-/G) variant and by the methylation of the promoter region. Moreover, the functional -241 (-/G) variant in the PPP2R1A promoter contributes to the decreased risk of HCC. These findings contribute novel information regarding the gene transcription of PPP2R1A regulated by the polymorphism and methylation in the promoter region through genetic and epigenetic mechanisms in hepatocarcinogenesis.

Inhibition effect of siRNA-downregulated UHRF1 on breast cancer growth.

The UHRF1 gene plays important roles in both cell proliferation through its NIRF_N domains, a PHD domain, an SRA domain, and a RING domain, and multidrug resistance in breast cancer treatment. In this work, a short-hairpin RNA (shRNA) lentiviral system was introduced in two human breast cancer cell lines (MDA-MB-231 and MCF-7) to downregulate the expression of UHRF1 and study the specific inhibition of UHRF1 in breast cancer growth. The effect of UHRF1-shRNA on breast cancer cell proliferation was examined using methylthiazoletetrazolium, bromodeoxyuridine, and colony formation assays. The proliferative potential of the UHRF1-shRNA-treated cells showed a remarkable decrease. Moreover, the downregulation of UHRF1 in both breast cancer cell lines significantly inhibited the colony formation capacity. Results suggested that the inhibition of UHRF1 via an RNA interference lentiviral system may provide an effective way for breast cancer therapy.

The paradoxical patterns of expression of indoleamine 2,3-dioxygenase in colon cancer.

BACKGROUND: One of the putative mechanisms of tumor immune escape is based on the hypothesis that carcinomas actively create an immunosuppressed state via the expression of indoleamine 2,3-dioxygenase (IDO), both in the cancer cells and in the immune cells among the tumor-draining lymph nodes (TDLN). In an attempt to verify this hypothesis, the patterns of expression of IDO in the cancer cells and the immune cells among colon cancers were examined. METHODS: Seventy-one cases of pathologically-confirmed colon cancer tissues matched with adjacent non-cancerous tissues, lymph node metastases, and TDLN without metastases were collected at the Sun Yat-sen Cancer Center between January 2000 and December 2000. The expression of IDO and Bin1, an IDO regulator, was determined with an immunohistochemical assay. The association between IDO or Bin1 expression and TNM stages and the 5-year survival rate in colon cancer patients was analyzed. RESULTS: IDO and Bin1 were detected in the cytoplasm of cancer cells and normal epithelium. In primary colon cancer, the strong expression of IDO existed in 9/71 cases (12.7%), while the strong expression of Bin1 existed in 33/71 cases (46.5%). However, similar staining of IDO and Bin1 existed in the adjacent non-cancerous tissues. Among the 41 cases with primary colon tumor and lymph node metastases, decreased expression of IDO was documented in the lymph node metastases. Furthermore, among the TDLN without metastases, a higher density of IDO+cells was documented in 21/60 cases (35%). Both univariate and multivariate analyses revealed that the density of IDO+cells in TDLN was an independent prognostic factor. The patients with a higher density of IDO+cells in TDLN had a lower 5-year survival rate (37.5%) than the cells with a lower density (73.1%). CONCLUSION: This study demonstrated paradoxical patterns of expression of IDO in colon cancer. The high density IDO+cells existed in TDLN and IDO was down-regulated in lymph nodes with metastases, implying that IDO in tumor and immune cells functions differently.

Expression of immune-related molecules in primary EBV-positive Chinese nasopharyngeal carcinoma: associated with latent membrane protein 1 (LMP1) expression.

To understand the role of Epstein-Barr virus (EBV) and viral products in associated with immunophenotype and clinical outcome of primary nasopharyngeal carcinoma (NPC), the expression levels of chemokines IFN-g-induced protein 10 (IP-10, CXCL10), stromal-derived factor-1 (SDF-1, CXCL12) and its receptor CXCR4 was investigated in 56 primary NPC biopsy specimens from Chinese NPC patients in parallels with LMP1 antigen and EBER1 by immunohistochemisty (IHC) and in situ hybridization (ISH). Moreover, the expression levels of HLA class I (b-microglobulin) and II antigen (HLA-DR), and co-stimulatory molecule CD54 were also evaluated in 31 out of these 56 patients using immunohistochemisty (IHC). Our results showed that (a) the elevated expression levels of IP10, SDF-1, CXCR4, b-microglobulin, HLA-DR and CD54 in NPC lesions was 66%, 36%, 30%, 42%, 55% and 69%, respectively. (b) High expression of SDF-1 was observed in advanced NPC (N stage, p < 0.05). (c) LMP1 expression correlated with upregulation of CXCR4 and translocation of CXCR4 to the nucleus of the tumor cells. This role of LMP1 in regulating the expression of CXCR4 was confirmed in the EBV positive NPC cell line C666 by inhibition of LMP1 expression with small interfering RNA (siRNA). Our findings provide new insights on the immune status of the malignant cells which may affect the outcome of immunotherapy in NPC. The differentiated nonkeratinizing and undifferentiated types of nasopharyngeal carcinoma (NPC) are associated with Epstein-Barr virus (EBV) in South China, which has the highest incidence rate in the world. The EBV latent type II antigens include nuclear antigen 1 (EBNA1), and latent membrane protein 1 (LMP1, in approximately 50%, seen in ref. 2) and protein 2 (LMP2), in addition small non-polyadenylated viral RNAs non-coding nuclear RNAs (EBERs) and BamHI-A rightward transcripts (BARTs) expressed in NPC tumor cells. The expressions of EBV antigens in NPC tumor cells provide the targets for adoptive immunotherapy. However, the poorly differentiated NPC is always characterized by the presence of a highly cellular lymphoid stroma admixed with tumor cells. However, the role of local immunity surrounding NPC cells and the role EBV and viral products expressed in tumor cell remain unclear, which is associated with the expression of immune-related molecules including chemokines and receptors, HLA class I and II antigens, and co-stimulatory molecules and the role of EBV and viral products to alter the expression of immune-related molecules on tumor cells. It has been reported that the expression pattern of immune related-molecules on tumor cells will affect the outcome of T-cell-based adoptive immunotherapy for NPC.

Functional inactivation of EBV-specific T-lymphocytes in nasopharyngeal carcinoma: implications for tumor immunotherapy.

Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus (EBV) associated malignancy with high prevalence in Southern Chinese. In order to assess whether defects of EBV-specific immunity may contribute to the tumor, the phenotype and function of circulating T-cells and tumor infiltrating lymphocytes (TILs) were investigated in untreated NPC patients. Circulating naïve CD3+CD45RA+ and CD4+CD25- cells were decreased, while activated CD4+CD25+ T-cells and CD3-CD16+ NK-cells were increased in patients compared to healthy donors. The frequency of T-cells recognizing seven HLA-A2 restricted epitopes in LMP1 and LMP2 was lower in the patients and remained low after stimulation with autologous EBV-carrying cells. TILs expanded in low doses of IL-2 exhibited an increase of CD3+CD4+, CD3+CD45RO+ and CD4+CD25+ cells and 2 to 5 fold higher frequency of LMP1 and LMP2 tetramer positive cells compared to peripheral blood. EBV-specific cytotoxicity could be reactivated from the blood of most patients, whereas the TILs lacked cytotoxic activity and failed to produce IFNgamma upon specific stimulation. Thus, EBV-specific rejection responses appear to be functionally inactivated at the tumor site in NPC.

[Sequence analysis of the CTL epitopes in transmembrane region of latent membrane protein 2 of Epstein-Barr virus derived from nasopharyngeal carcinoma cells].

BACKGROUND & OBJECTIVE: Epstein-Barr virus (EBV) in nasopharyngeal carcinoma (NPC) cells expresses Epstein-Barr nuclear antigen 1 (EBNA1), latent membrane protein 1 (LMP1), and LMP2. LMP2 is an ideal target for immunotherapy because LMP2 mRNA is detected in 100% nasopharyngeal carcinoma cells and LMP2 protein shows stronger immunogenity than the rest 2 viral proteins. This study was to analyze the sequence of CTL epitopes in the transmembrane region of LMP2 to optimize LMP2-targeted immunotherapy. METHODS: Genomic DNA was extracted from 20 biopsies of NPC and 3 biopsies of normal nasopharynx from Cantonese. The transmembrane region of LMP2 gene was amplified with hemi-nest polymerase chain reaction (PCR), and then sequenced directly. RESULTS: As compared with prototype B95.8 cells, the transmembrane region of LMP2 gene, derived from Cantonese NPC and normal nasopharynx tissues, had 14 base pair substitutions, resulting in 6 amino acid substitutions. Among these substitutions, 3 changed amino acids were located in 4 HLA-restricted CTL epitopes (SSC, TYG, CLG, and VMS). Among these polymorphisms, the VMS variation was first identified. The sequence changes of the LMP2 derived from NPC was the same as those of the LMP2 from normal nasopharynx, indicating that those variations were due to geographic-associated polymorphisms rather than NPC-associated mutations. CONCLUSION: Polymorphisms of LMP2 exist in EBV derived from Cantonese, resulting in 4 CTL epitope variations, which implicates that the effect of LMP2 polymorphisms should be considered when LMP2-targeted vaccine is designed for immunotherapy.