Evaluation of Anti-Hyperglycemia and Complications of Red and Black Thai Jasmine Rice Cultivars in Streptozotocin-Induced Diabetic Rats.

The phytochemical constituents of red (RR) and black (BR) rice extracts were determined using high-pressure liquid chromatography (HPLC). Phytochemical screening revealed the presence of catechin, rutin, isoquercetin, cyanidin 3-glucoside, cyanidin 3-O-rutinoside, peonidin and quercetin. The anti-diabetic activities of RR and BR extracts on diabetic complications were examined in a streptozotocin-induced diabetic rat model. Rats (n = 80) were divided into 10 groups (n = 8 rats per group). Healthy and diabetic RR or BR-treated groups received 10, 50, or 200 mg of RR or BR per kg of body weight daily for 45 days. The results demonstrated significantly improved glucose control in rats administered RR or BR, while triglyceride and cholesterol levels were reduced in the diabetic groups. Moreover, RR or BR treatment led to decreased levels of malondialdehyde, aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen, and creatinine. Further, glutathione concentration was significantly increased in both serum and liver tissue from RR- and BR-treated diabetic rats.

Cytotoxic activity of effector T cells against cholangiocarcinoma is enhanced by self-differentiated monocyte-derived dendritic cells.

Cholangiocarcinoma (CCA) is a cancer of the bile ducts that is associated with poor prognosis and poor treatment outcome. Approximately one-third of CCA patients can undergo surgery, but the recurrence rate is high and chemotherapy often cannot satisfactorily prolong survival. Cellular immunotherapy based on adoptive T-cell transfer is a potential treatment for CCA; however, the development of this technology and the search for an appropriate tumor-associated antigen are still ongoing. To enhance the cytotoxic activity of effector T cells against CCA, we developed self-differentiated monocyte-derived dendritic cells (SD-DC) presenting cAMP-dependent protein kinase type I-alpha regulatory subunit (PRKAR1A), which is an overexpressed protein that plays a role in the regulation of tumor growth to activate T cells for CCA cell killing. Dendritic cells (DCs) transduced with lentivirus harboring tri-cistronic cDNA sequences (SD-DC-PR) could produce granulocyte-macrophage colony-stimulating factor, interleukin-4, and PRKAR1A. SD-DC showed similar phenotypes to those of DCs derived by conventional method. Autologous effector T cells (CD3+, CD8+) activated by SD-DC-PR exhibited greater cytotoxic activity against CCA than those activated by conventionally-derived DCs. Effector T cells activated by SD-DC-PR killed 60% of CCA cells at an effector-to-target ratio of 15:1, which is approximately twofold greater than the cell killing performance of those stimulated with control DC. The cytotoxic activities of effector T cells activated by SD-DC-PR against CCA cells were significantly associated with the expression levels of PRKR1A in CCA cells. This finding that SD-DC-PR effectively stimulated autologous effector T cells to kill CCA cells may help to accelerate the development of novel therapies for treating CCA.

Enhanced cytotoxic activity of effector T-cells against cholangiocarcinoma by dendritic cells pulsed with pooled mRNA.

Cholangiocarcinoma is a malignancy of bile duct epithelia with an increasing in incidence rate worldwide. Surgery is the only curative treatment, while adjuvant chemotherapy and radiotherapy render poor responses. Cell-based immunotherapy is a potential strategy for cholangiocarcinoma treatment. However, variation of tumor antigens in cholangiocarcinoma leads to the ineffectiveness of cell-based immunotherapy. In this study, we examined the activation of effector T-cells by dendritic cells pulsed with protein lysate or total RNA from cholangiocarcinoma cell lines for their cytolytic activity against cholangiocarcinoma. Broad-spectrum antigen types with respect to RNA antigen sources were obtained from combination of three cholangiocarcinoma cell lines (KKU-213, KKU-100, and KKU-055). Compared with protein lysate-pulsed dendritic cells, total RNA-pulsed dendritic cells induced anti-tumor effector T-cell response with higher killing ability to KKU-100 and KKU-213 cells compared with protein lysate-pulsed dendritic cells. Moreover, pooled messenger RNA from three cholangiocarcinoma cell lines significantly increased the specific killing capacity of activated lymphocytes against KKU-213 cells. These results suggest that activation of anti-tumor effector T-cells against cholangiocarcinoma by RNA-pulsed dendritic cells is more effective than that by protein lysate-pulsed dendritic cells. In addition, pulsing dendritic cells with pooled messenger RNA from multiple cell lines enhanced the efficacy of a cellular immune response against cholangiocarcinoma.

Enhancing cholangiocarcinoma immunotherapy with adoptive T cells targeting HLA-restricted neoantigen peptides derived from driver gene mutations.

Precision immunotherapy, driven by genomic and bioinformatic advancements, has emerged as a promising and viable approach to combat cancer. Targeting neoantigens offers the advantage of specific immune responses with minimal off-tumor toxicity. In this study, we investigated the potential of adoptive T cells activated by HLA-restricted neoantigen peptides from driver gene mutations for treating cholangiocarcinoma (CCA), a highly aggressive cancer with poor prognosis and high mortality rates. Through whole exome sequencing of CCA cell lines, KKU-213A and KKU-100, we identified mutations in common driver genes and predicted corresponding HLA-restricted peptides. Peptides from KRAS, RNF43, and TP53 mutations exhibited strong binding affinity to HLA-A11, as validated through molecular docking and T2-cell binding assays. Dendritic cells (DCs) from healthy donors expressing HLA-A* 11:01, pulsed with individual or pooled peptides, showed comparable levels of costimulatory molecules (CD11c, CD40, CD86, and HLA-DR) to conventional DCs but higher expression of maturation markers, CD80 and CD86. Autologous HLA-A* 11:01-restricted T cells, activated by peptide-pulsed DCs, effectively lysed KKU-213A (HLA-A*11:01) cells, outperforming conventional tumor lysate-pulsed DCs. This effect was specific to HLA-A* 11:01-restricted T cells and not observed in KKU-100 (HLA-A*33:03) cells. Moreover, HLA-A* 11:01-restricted T cells exhibited elevated levels of IFN-gamma, granulysin, and granzyme B, indicating their potent anti-tumor capabilities. These findings underscore the specificity and efficiency of HLA-A* 11:01-restricted T cells targeting KRAS, RNF43, TP53 mutated CCA cells, and offer valuable insights for developing immunotherapeutic strategies and therapeutic peptide-vaccines for CCA treatment.

Curcumin-loaded albumin submicron particles with potential as a cancer therapy: an in vitro study.

Curcumin (CUR), a polyphenolic compound, shows promising biological properties, particularly antioxidant activity. However, its medical applications are limited due to its low water solubility, bioavailability, and pH-instability. CUR-loaded albumin microparticles (CUR-HSA-MPs) of submicron size in the range of 800 to 900 nm and a zeta potential of -15 mV were prepared. The CUR loading efficiency was up to 65%. A maximum release of 37% of the encapsulated CUR was observed within 6 h when the CUR-HSA-MPs were dispersed in 50% ethanol in PBS at pH 7, while in RPMI 1640 medium the release was 7%. This demonstrates a sustainable release. The in vitro cytotoxicity of CUR-HSA-MPs showed promising anticancer potential against human hepatocellular carcinoma (Huh-7) and human breast adenocarcinoma (MCF-7) cell lines, although this effect was less pronounced in human dermal fibroblasts (HDFB) and human cholangiocyte (MMN) cell lines. Confocal microscopy was used to confirm the uptake of CUR-HSA-MPs by cancer cells. Our studies revealed that HSA-MPs are potentially promising vehicles for increasing the solubility and bioavailability of CUR.

Anti-cancer effect of a phytochemical compound - 7R-acetylmelodorinol - against triple-negative breast cancer cells.

Triple-negative breast cancer (TNBC) is a highly aggressive subtype currently lacking effective treatment options. Consequently, novel and effective drugs or compounds are urgently needed to treat TNBC. Therefore, this study aimed to evaluate the potential of 7R-acetylmelodorinol (7R-AMDL), a phytochemical compound isolated from Xylopia pierrei Hance, a plant found in Thailand, as a novel therapeutic agent for TNBC. MTT and clonogenic assays showed that 7R-AMDL significantly reduced the survival of breast cancer cell lines, with a markedly potent effect on MDA-MB-231 cells. Flow cytometry showed that treating MDA-MB-231 cells with 7R-AMDL at the concentration of dose 8 µM significantly increased early and late apoptosis after 24 and 48 h compared to the control group (p < 0.0001). The highest tested 7R-AMDL dose upregulated the death receptors and their ligands, with extrinsic and intrinsic apoptosis pathways significantly activated via the caspase cascade, compared to the untreated group (p < 0.05). In addition, immunoblots showed decreased BCL2-like 1 (BCL2L1/Bcl-xL) expression (p < 0.0001). Furthermore, wound healing and Transwell assays showed that at a non-cytotoxic dose (≤4 µM), 7R-AMDL significantly inhibited the MDA-MB-231 cell migration and invasion. This reduction in cell migration was associated with decreased matrix metallopeptidase 9 (MMP-9) expression (p < 0.01) and nuclear factor kappa B (NF-κB) activation (p < 0.05). Altogether, 7R-AMDL has anti-cancer effects against TNBC and the potential to be further developed and evaluated for treating this disease.

Efficacy and safety of nanoparticle albumin-bound paclitaxel in advanced non-small cell lung cancer: A systematic review and meta-analysis of clinical trials and observational studies.

Background: The efficacy and safety of nanoparticle albumin-bound paclitaxel (nab-paclitaxel) in advanced non-small cell lung cancer (NSCLC) have yielded inconsistent findings. Materials and methods: We conducted a systematic review and meta-analysis, including comparative and noncomparative trials and cohort studies, to assess the efficacy and safety of nab-paclitaxel in advanced NSCLC. The search covered PubMed, CENTRAL, Scopus, and ClinicalTrials.gov until October 2022. Efficacy outcomes (OR, PR, progressive disease, OS, and PFS) and safety outcomes (neutropenia, leukopenia, thrombocytopenia, anemia, and sensory neuropathy) were analyzed. Results: Our meta-analysis included data from 35 studies (9 RCTs, 2 cohort studies, and 24 noncomparative studies). Nab-paclitaxel significantly improved OR rate (RRRCT 1.35 [95% CI 1.19, 1.53], I2 = 36.6%; RRcohort 1.67 [95% CI 1.30, 2.14], I2 = 4.3%) and PR rate (RRRCT 1.34 [95% CI 1.18, 1.53], I2 = 38.8%; RRcohort 1.59 [95% CI 1.22, 2.07], I2 = 19.4%) compared to the control group. It further demonstrated more pronounced benefits in squamous cell carcinoma and as a second-line treatment. Pooled evidence from the RCTs also indicated improved OS (HR 0.90 [95% CI 0.81, 0.99], I2 = 9.2%) and PFS (HR 0.84 [95% CI 0.76, 0.93], I2 = 14.5%) However, evidence on the reduction of adverse events with nab-paclitaxel treatment was insufficient, and biases in study selection and detection may have influenced the results. Conclusions: Nab-paclitaxel enhances OR, PR, PFS, and marginally improves OS in advanced NSCLC, particularly in patients with prior chemotherapy. Further research is needed to establish its safety advantages.

Rare prenylated isoflavonoids from the young twigs of Millettia extensa and their cytotoxic activities.

Three new isoflavonoids, millexatins N-P (1-3), along with seven known compounds (6-10), were isolated from the acetone extract of the young twigs of Millettia extensa. The structures were characterized by NMR spectroscopic and mass spectrometric analyses. Millexatin N (1) is an unusual geminal diisoprenylated isoflavone with a modified ring A. Millexatin P (3) is an unusual isoflavone with a cyclohexyl substituent on ring B, which is extremely rare in nature. The isolated metabolites (1, 2, and 6-10) were evaluated for cytotoxicities against MDA-MB231, Huh-7, KKU-100 and normal human dermal fibroblast (NHDF) cell lines. Only compounds 1, 6 and 8 showed cytotoxicities against all cell lines with IC50 values ranging from 13.9 to 30.9 µM.

High prevalence of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae isolates: A 5-year retrospective study at a Tertiary Hospital in Northern Thailand.

Background: The global emergence and spread of extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales, especially Escherichia coli and Klebsiella pneumoniae, have been recognized as a public health concern as severe infections caused by these microorganisms increase morbidity and mortality. This study aimed to assess the prevalence of ESBL-positive E. coli and K. pneumoniae strains isolated from hospitalized patients in Chiangrai Prachanukroh hospital, Chiangrai province, Thailand. Methods: This retrospective analysis was conducted from January 2016 to December 2020. A total of 384,001 clinical specimens were collected aseptically and further cultivated on an appropriate medium. All clinical isolates (one isolate per patient) were identified based on standard laboratory methods. Antibiotic susceptibility testing was performed by the Kirby Bauer disc diffusion technique following CLSI guidelines. ESBL production was screened with ceftazidime and cefotaxime discs based on the CLSI recommendations. Phenotypic confirmation of ESBL production was carried out using a double-disc synergy technique following the CLSI standard. Results: Of a total of 384,001 clinical samples analyzed for bacterial species identification, 11,065 (2.9%) tested positive for E. coli and 5,617 (1.5%) for K. pneumoniae. Approximately 42.5% (4,706/11,065) of E. coli and 30.2% (1,697/5,617) of K. pneumoniae isolates were classified as ESBL producers. A higher proportion of ESBL producers was found in patients older than 60 years and male groups. The highest infection rates of ESBL-positive pathogens were observed among patients in a medical unit. ESBL-producing E. coli and K. pneumoniae isolates were predominantly found in urine and sputum, respectively. ESBL producers exhibited a high resistance rate to ampicillin (99.8-100%), cefazolin (100%), cefotaxime (100%), fluoroquinolones, and trimethoprim/sulfamethoxazole. Conclusions: This study demonstrated the high prevalence and emerging antibiotic resistance of ESBL-positive E. coli and K. pneumoniae isolates from patients admitted to a provincial hospital in northern Thailand. Most ESBL-producing strains were highly resistant to several antimicrobial agents apart from carbapenems and aminoglycosides. These findings indicated that carbapenems and aminoglycosides should be advised as the first-line drugs of choice for serious infections with ESBL-producing Enterobacterales.

Marginaols G-M, anti-inflammatory isopimarane diterpenoids, from the rhizomes of Kaempferia marginata.

Marginaols G-M, a series of undescribed isopimarane diterpenoids, together with four known analogs were isolated from the rhizomes of Kaempferia marginata. The structures of these isolated compounds were characterized using high-resolution mass spectrometry and extensive 1D- and 2D-nuclear magnetic resonance (NMR) analyses. In addition, the absolute configurations of marginaol G and H were determined by X-ray crystallographic analysis and comparison with the literature values. When compared to the standard drug dexamethasone (IC50 4.7 µM), marginaol G, H, and 6ß-acetoxysandaracopimaradien-1α,9α-diol had an intriguing anti-inflammatory effect on NO inhibition in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages, with IC50 values ranging from 4.5 to 7.3 µM and being less cytotoxic to the cells. The anti-inflammatory action of these isopimarane diterpenoids from K. marginata supports the use of Thai traditional medicine for inflammation treatment.

Development of a Novel Anti-CD19 CAR Containing a Fully Human scFv and Three Costimulatory Domains.

Second-generation anti-CD19-chimeric antigen receptor T cells (anti-CD19-CAR2 T cells) are effective for treating B-cell malignancies; however, anti-CD19-CAR2 T cells can induce human anti-mouse immune responses because anti-CD19 single-chain variable fragment (scFv) in the CAR molecules is derived from a murine FMC63 (mFMC63) monoclonal antibody. Consequently, the persistence of mFMC63-CAR2 T cells and their therapeutic efficiency in patients are decreased, which results in tumor relapse. In an attempt to remedy this shortcoming, we generated a new anti-CD19-CAR T cells containing fully human anti-CD19 scFv (Hu1E7-CAR4 T cells) to pre-clinically evaluate and compare with mFMC63-CAR4 T cells. The human anti-CD19 scFv (Hu1E7) was isolated from a human scFv phage display library and fused to the hinge region of CD8α, the transmembrane domain of CD28, three intracellular costimulatory domains (CD28, 4-1BB, and CD27), and a CD3ζ signaling domain (28BB27ζ). Compared to mFMC63-CAR2 T cells (BBζ) and mFMC63-CAR3 (BB27ζ), the mFMC63-CAR4 T cells (28BB27ζ) exerted superior anti-tumor activity against Raji (CD19+) target cell. The Hu1E7-CAR4 and mFMC63-CAR4 T cells demonstrated comparable cytotoxicity and proliferation. Interestingly, compared to mFMC63-CAR4 T cells, the Hu1E7-CAR4 T cells secreted lower levels of cytokines (IFN-γ and TNF-α), which may be due to the lower binding affinity of Hu1E7-CAR4 T cells. These findings demonstrated the successfulness in creation of a new CAR T cells containing a novel fully human-derived scFv specific to CD19+ cancer cells. In vivo studies are needed to further compare the anti-tumor efficacy and safety of Hu1E7-CAR4 T cells and mFMC63-CAR4 T cells.

Endoplasmic reticulum stress, unfolded protein response and autophagy contribute to resistance to glucocorticoid treatment in human acute lymphoblastic leukaemia cells.

Acute lymphoblastic leukaemia (ALL) is the most frequent childhood cancer and, although it is highly treatable, resistance to therapy, toxicity and side effects remain challenging. The synthetic glucocorticoid (GC) dexamethasone (Dex) is commonly used to treat ALL, the main drawback of which is the development of resistance to this treatment. The aim of the present study was to investigate potential molecular circuits mediating resistance and sensitivity to GC­induced apoptosis in ALL. The leukaemia cell lines CEM­C7­14, CEM­C1­15 and MOLT4 treated with chloroquine (CLQ), thapsigargin (TG) and rotenone (ROT) were used to explore the roles of autophagy, endoplasmic reticulum (ER) stress/unfolded protein response (UPR) and reactive oxygen species (ROS) generation in the response to GC treatment. ROS levels were associated with increased cell death and mitochondrial membrane potential in rotenone­treated CEM cells. Autophagy inhibition by CLQ exhibited the strongest cytotoxic effect in GC­resistant leukaemia. Autophagy may act as a pro­survival mechanism in GC­resistant leukaemia since increasing trends in beclin­1 and microtubule­associated protein 1 light chain 3α levels were detected in CEM­C1­15 and MOLT4 cells treated with Dex, whereas decreasing trends in these autophagy markers were observed in CEM­C7­14 cells. The intracellular protein levels of the ER stress markers glucose­regulated protein (GRP)78 and GRP94 were stimulated by Dex only in the GC­sensitive cells, suggesting a role of these chaperones in the GC­mediated ALL cell death. Increased cell surface levels of GRP94 were recorded in CEM­C7­14 cells treated with combination of Dex with TG compared with those in cells treated with TG alone, whereas decreasing trends were observed in CEM­C1­15 cells under these conditions. Taken together, the results of the present study demonstrated that autophagy may be a pro­survival mechanism in GC­resistant leukaemia, and by modulating intracellular and surface GRP94 protein levels, Dex is involved in the regulation of ER stress/UPR­dependent cell death and immune surveillance. These observations may be of clinical importance if confirmed in patients.

Suppression of TGF-ß and IL-10 receptors on self-differentiated dendritic cells by short-hairpin RNAs enhanced activation of effector T-cells against cholangiocarcinoma cells.

Cholangiocarcinoma (CCA) is an aggressive tumor that is associated with high rates of recurrence and mortality. This is due, in part, to the fact that CCA cells and their microenvironment secrete immunosuppressive cytokines, transforming growth factor-ß (TGF-ß) and interleukin-10 (IL-10), that inhibit dendritic cell (DC) functions, which, in turn, results in the decreased anti-tumor activity of T-cells. We hypothesized that the TGF-ß receptor and IL-10 blockade on dendritic cells would improve DC function, thereby allowing improved activation of T cells against CCA cells. To test our hypothesis, we generated self-differentiated DCs (SD-DCs) via transduction of human peripheral blood monocytes with lentivirus expressing IL-4 and GM-CSF. SD-DCs were transduced with a second lentivirus containing short-hairpin RNAs (shRNAs) to knock-down TGF-ßRII and IL-10RA mRNAs. Immunoblot confirmed the reduced expression levels of TGF-ß and IL-10 receptors in both SD-DCs that were transduced with a single and/or combination of lentiviruses containing shRNAs. SD-DCs were thereafter pulsed with tumor antigens extracted from CCA cell lines in an effort to activate DC function. MHC class II (HLA-DR) and co-stimulatory molecules (CD40 and CD86) on SD-DCs were upregulated to levels comparable to those on DCs generated by the conventional method. Suppression of TGF-ß and IL-10 receptors on SD-DCs influenced the effector T-cells to produce IFN-γ, which enhanced their ability to kill CCA cells. The preparation of adoptive effector T-cells holds the potential of becoming a novel therapy for cellular immunotherapy in CCA.

Gemcitabine enhances cytotoxic activity of effector T-lymphocytes against chemo-resistant cholangiocarcinoma cells.

Cholangiocarcinoma (CCA) can resist chemotherapy resulting in treatment failure. Gemcitabine, a chemotherapeutic drug, can sensitize cancer cells to become susceptible to cytotoxic T-lymphocytes (CTLs). We, therefore, hypothesized that a combination of gemcitabine and CTLs would be more effective for CCA treatment than individual therapy. To test this hypothesis, we conducted an in vitro study using gemcitabine combined with CTLs to treat gemcitabine-resistant CCA (KKU-213) cells. KKU-213 cells were pretreated with gemcitabine and tested for killing by CTLs activated by dendritic cells that were prepared by three different methods, including: (i) monocyte-derived dendritic cells pulsed with cancer cell lysate (Mo-DC + Lys), (ii) self-differentiated dendritic cells pulsed with cancer-cell lysate (SD-DC + Lys), and (iii) SD-DC presenting tumor-associated antigen PRKAR1A (SD-DC-PR). KKU-213 cells pretreated with gemcitabine were killed by CTLs activated by either SD-DC + Lys or SD-DC-PR more efficiently than those activated by Mo-DC + Lys. Furthermore, KKU-213 cells pretreated with a low dose (2 µM) of gemcitabine significantly enhanced the cytotoxic activity of CTLs activated by either SD-DC + Lys or SD-DC-PR at all evaluated effector (E) to target cell (T) ratios. At an E:T ratio of 5:1, KKU-213 cells pretreated with gemcitabine enhanced the cytotoxic activity of CLTs by approximately 2.5-fold (greater than 50% cell death) compared to untreated condition. The upregulation of HLA class I upon pretreatment of KKU-213 cells with gemcitabine may suggest a mechanism that leads to alteration of the antigen presentation process to promote CTL functions. These findings support the concept of combination therapy for overcoming chemo-resistant CCA.

Cytolytic Activity of Effector T-lymphocytes Against Hepatocellular Carcinoma is Improved by Dendritic Cells Pulsed with Pooled Tumor Antigens.

Cellular immunotherapy is a promising new therapeutic approach for hepatocellular carcinoma (HCC), which has a high recurrence rate, irrespective of the treatment administered. In this study, we attempted to improve the cytolytic activity of effector T-lymphocytes against HCC. T-lymphocytes were activated by monocyte-derived dendritic cells (DCs) pulsed with cell lysate or RNA prepared from HCC cell lines. Monocytes were activated for differentiation into DCs by treatment with the IL4 and GM-CSF. DCs were pulsed with cell lysate or RNA prepared from a single cell line or combinations of two or three HCC cell lines, and then co-cultured with autologous T-lymphocytes with the intent of creating specific cytotoxicity. We discovered that DCs pulsed with total RNA effectuated greater T-lymphocyte function than DCs pulsed with total cell lysate, as evidenced by greater cytolytic activities against HCC target cells. The percentage of Huh7, HepG2, and SNU449 cell apoptosis at effector:target ratio of 10:1 was 42.6 ± 4.5% (p = 0.01), 33.6 ± 3.1% (p = 0.007), and 21.4 ± 1.4% (p < 0.001), respectively. DCs pulsed with pools of antigens prepared from three cell lines improved the cytolytic function of effector T-lymphocytes by approximately two-fold (p < 0.001), which suggests that this approach be further developed and applied for adoptive transfer treatment of HCC.

Sirtuin Family Members Selectively Regulate Autophagy in Osteosarcoma and Mesothelioma Cells in Response to Cellular Stress.

The class III NAD+ dependent deacetylases-sirtuins (SIRTs) link transcriptional regulation to DNA damage response and reactive oxygen species generation thereby modulating a wide range of cellular signaling pathways. Here, the contribution of SIRT1, SIRT3, and SIRT5 in the regulation of cellular fate through autophagy was investigated under diverse types of stress. The effects of sirtuins' silencing on cell survival and autophagy was followed in human osteosarcoma and mesothelioma cells exposed to DNA damage and oxidative stress. Our results suggest that the mitochondrial sirtuins SIRT3 and 5 are pro-proliferative under certain cellular stress conditions and this effect correlates with their role as positive regulators of autophagy. SIRT1 has more complex role which is cell type specific and can affect autophagy in both positive and negative ways. The mitochondrial sirtuins (SIRT3 and SIRT5) affect both early and late stages of autophagy, whereas SIRT1 acts mostly at later stages of the autophagic process. Investigation of potential crosstalk between SIRT1, SIRT3, and SIRT5 revealed several feedback loops and a significant role of SIRT5 in regulating SIRT3 and SIRT1. Results presented here support the notion that sirtuin family members play important as well as differential roles in the regulation of autophagy in osteosarcoma vs. mesothelioma cells exposed to DNA damage and oxidative stress, and this can be exploited in increasing the response of cancer cells to chemotherapy.

Inhibition of IL-10 and TGF-ß receptors on dendritic cells enhances activation of effector T-cells to kill cholangiocarcinoma cells.

Tumor escapes host immune responses by producing immunosuppressive cytokines, such as IL-10 and TGF-ß, secreted into the tumor microenvironment. These cytokines play important roles in the suppression of dendritic cell (DC) function, leading to decreased immune responses of the effector CD4+ and CD8+ T cells. To improve DC functions and enhance cytolytic activity of activated effector T-cells, we suppressed the effect of these cytokines on DCs by using specific neutralizing antibodies that inhibit IL-10 and TGF-ß receptors. Monocyte-derived DCs generated in vitro showed up-regulation of MHC (HLA-DR) and co-stimulatory molecules (CD40 and CD86). The IL-10 and TGF-ß receptors were expressed and localized on cell membrane of DCs, as shown by Western blot analysis and immunofluorescence staining, whereas the IL-10 and TGF-ß ligands were detected in the culture supernatants of DCs and cholangiocarcinoma (CCA) cell line, respectively. Inhibition of the IL-10 and TGF-ß receptors on DCs by specific neutralizing antibodies significantly increased level of IFN-γ and enhanced cytolytic activity of the DC-activated effector T-cells against CCA cell line. These results indicate that the IL-10 and TGF-ß receptors are the targets for inhibition to increase DC functions and enhance cytolytic activity of the DC-activated effector T-cells against CCA cells. Thus, inhibition of the IL-10 and TGF-ß receptors on DCs is crucial in the preparation of DC-activated effector T cells for adoptive T-cell therapy.

Changes in the NS1 gene of avian influenza viruses isolated in Thailand affect expression of type I interferon in primary chicken embryonic fibroblast cells.

The non-structural protein 1 (NS1) of avian influenza virus was defined as one of the virulent factors. To understand the effect of NS1 protein of influenza virus H5N1 isolated in Thailand on type I (α/ß) interferon (IFN) synthesis, five reverse genetic viruses were constructed and used as models. The viruses were generated using NS genomic segment from A/Peurto Rico/8/1934 (H1N1) and four avian influenza viruses isolated from the first outbreak in Thailand. All the viruses have the rest of the genome from A/Peurto Rico/8/1934 (H1N1). The constructed viruses were named (1) NS1 PR8/34, (2) NS1 wild type, (3) NS1 L15FD53G, (4) NS1 N171I and (5) NS1 E71K, respectively. The type I (α/ß) IFN gene expression in control and infected primary chicken embryonic fibroblast cells were analyzed by quantitative polymerase chain reaction. The results show that the inhibition of IFN-ß gene expression by NS1 wild type infected cells is stronger than NS1 N171I, NS1 E71K, NS1 PR8/34 and NS1 L15FD53G, respectively. The data suggest that the difference of amino acid sequence of NS1 protein contributes to the IFN-ß antagonist. In contrast, the difference of the NS1 protein does not influence in the IFN-α antagonistic activity.