Epigenetic modulations in triple-negative breast cancer: Therapeutic implications for tumor microenvironment.

Triple-negative breast cancer (TNBC) is an aggressive subtype lacking estrogen receptors, progesterone receptors and lacks HER2 overexpression. This absence of critical molecular targets poses significant challenges for conventional therapies. Immunotherapy, remarkably immune checkpoint blockade, offers promise for TNBC treatment, but its efficacy remains limited. Epigenetic dysregulation, including altered DNA methylation, histone modifications, and imbalances in regulators such as BET proteins, plays a crucial role in TNBC development and resistance to treatment. Hypermethylation of tumor suppressor gene promoters and the imbalance of histone methyltransferases such as EZH2 and histone deacetylases (HDACs) profoundly influence tumor cell proliferation, survival, and metastasis. In addition, epigenetic alterations critically shape the tumor microenvironment (TME), including immune cell composition, cytokine signaling, and immune checkpoint expression, ultimately contributing to immune evasion. Targeting these epigenetic mechanisms with specific inhibitors such as EZH2 and HDAC inhibitors in combination with immunotherapy represents a compelling strategy to remodel the TME, potentially overcoming immune evasion and enhancing therapeutic outcomes in TNBC. This review aims to comprehensively elucidate the current understanding of epigenetic modulation in TNBC, its influence on the TME, and the potential of combining epigenetic therapies with immunotherapy to overcome the challenges posed by this aggressive breast cancer subtype.

Understand the Chinese Z Generation consumers' Green hotel visit intention: An Extended Theory of Planned Behavior Model.

In the context of growing environmental concerns and a shift towards sustainable tourism, understanding the behaviors of younger generations, particularly Generation Z, becomes crucial for the hotel industry. This study investigates the intentions of Chinese Generation Z consumers to visit green hotels, using an extended Theory of Planned Behavior (TPB) model incorporating multi-dimensional green perceived value. A questionnaire survey with 436 participants was conducted, and structural equation modeling was employed for data analysis. The study reveals that Functional value significantly shapes the inclination towards green hotels among Chinese Generation Z. Emotional value and Subjective norms also positively influence visit intentions, whereas social value, although not a significant driver, provides insights into the distinct nature of green consumption behaviors. This study's findings offer strategic insights for green hotel operators and policymakers to attract this demographic segment, emphasizing Chinese Generation Z consumers' unique preferences and values.

CyHV-2 infection triggers mitochondrial-mediated apoptosis in GiCF cells by upregulating the pro-apoptotic gene ccBAX.

Apoptosis is a physiological cell death phenomenon, representing one of the fundamental physiological mechanisms for maintaining homeostasis in living organisms. Previous studies have observed typical apoptotic features in Carassius auratus gibelio caudal fin cell (GiCF) infected with Cyprinid herpesvirus 2 (CyHV-2), and found a significant up-regulation of ccBAX expression in these infected cells. However, the specific apoptotic mechanism involved remains unclear. In this study, we utilized the GiCF cell line to investigate the apoptotic mechanism during CyHV-2 infection. Immunofluorescence staining revealed translocation of ccBAX into mitochondria upon CyHV-2 infection. Flow cytometry analysis demonstrated that overexpression of ccBAX expedited virus-induced apoptosis, characterized by heightened mitochondrial depolarization, increased transcriptional levels of Cytochrome c (Cyto c) in both the cytoplasm and mitochondria, and augmented Caspase 3/7 enzyme activity. Bax inhibitor peptide V5 (BIP-V5), an inhibitor interfering with the function of Bax proteins, inhibited Bax-mediated apoptotic events through the mitochondrial pathway and attenuated apoptosis induced by CyHV-2. In this study, it was identified for the first time that CyHV-2 induces apoptosis via the mitochondrial pathway in GiCF cells, bridging an important gap in our understanding regarding cell death mechanisms induced by herpesvirus infections in fish species. These findings provide a theoretical basis for comprehending viral apoptotic regulation mechanisms and the prevention and control of cellular pathologies caused by CyHV-2 infection.

Habitual Expressive Suppression of Positive, but not Negative, Emotions Consistently Predicts Lower Well-being across Two Culturally Distinct Regions.

Habitual expressive suppression (i.e., a tendency to inhibit the outward display of one's emotions; hereafter suppression) is often conceptualized as a maladaptive emotion regulation strategy. Yet, is this equally true for suppression of positive and of negative emotions? Across three studies and seven samples (total N > 1300 people) collected in two culturally distinct regions (i.e., Taiwan and the US), we examined the separability and distinct well-being effects of suppressing positive vs. negative emotions. Results consistently showed that (a) people suppressed their positive (vs. negative) emotions less, (b) the construct of suppression of positive (vs. negative) emotions was conceptually farther away from that of suppression of emotions in general, (c) suppression of positive and of negative emotions were only moderately correlated, and (d) only suppression of positive, but not negative, emotions, predicted lower well-being. An internal meta-analysis (k = 52 effect sizes) showed that these associations were robust to the inclusion of age, gender, and region as covariates. Future research may further probe the respective links between suppression of positive and of negative emotions and well-being across more cultural regions and across the life-span.

The loss of B7-H4 expression in breast cancer cells escaping from T cell cytotoxicity contributes to epithelial-to-mesenchymal transition.

BACKGROUND: B7 homology 4 (B7-H4), a potential target for cancer therapy, has been demonstrated to inhibit T cell cytotoxicity in the early stages of breast cancer. However, B7-H4 manipulating breast tumor immune microenvironment (TIME) in the tumor progression remains unknown. METHODS: We engineered T cells with B7-H4-specific chimeric antigen receptors (CARs) and performed a T cell co-culture assay to characterize B7-H4 expression level in breast cancer cells escaping from T cell cytotoxicity. We generated B7-H4 knockout (KO) and overexpression (OE) breast cancer cells to determine the epithelial-to-mesenchymal transition (EMT) and stemness characteristics in vitro and in vivo, including tumor proliferation, migration, metastasis and chemoresistance. The Cancer Genome Atlas breast cancer database was accessed to investigate the correlation between B7-H4 expression levels and EMT characteristics in patients with breast cancer. RESULTS: Our result found that B7-H4 expression level was significantly reduced in a subset of breast cancer cells that escaped from the cytotoxicity of B7-H4 CAR-T cells. Compared with wild type cells, B7-H4 KO cells prompt EMT and stemness characteristics, including migration, invasion and metastasis, and OE cells vice versa. The increase in H3K27me3 in KO cells confirmed the epigenetic reprogramming of cancer stem cells. The IC50 of doxorubicin or oxaliplatin significantly increased in KO cells, which was in agreement with a decrease in OE cells. Moreover, a trend of downregulated B7-H4 from stage I to stage II breast cancer patients indicates that the low-expressing B7-H4 breast cancer cells escaping from TIME have spread to nearby breast lymph nodes in the cancer progression. CONCLUSIONS: Our study illuminates the novel role of renouncing B7-H4 in breast cancer cells through immune escape, which contributes to EMT processes and provides new insights for breast cancer treatments.

Believe, express, and enjoy: utility beliefs about social emotion expression consistently predict satisfactory outcomes.

The present study investigates the association between people's beliefs about emotion and their overall satisfaction with a social interaction. We focus on three specific aspects to examine this association: (a) utility beliefs-a dimension of emotion beliefs; (b) emotion expression-an emotion channel; and (c) four social emotions-anger, other-embarrassment, gratitude, and other-pride. We examine whether people's utility beliefs about expressing a social emotion can predict their evaluation of a social interaction when they express (vs. suppress) their social emotion. Results (N = 209) consistently show that when people express their social emotion, their utility beliefs positively predict their satisfaction with an event. However, when people suppress their gratitude, their utility beliefs negatively predict their satisfaction, an effect not observed in the other three emotion events. These findings corroborate the claim that emotion beliefs impact people's emotional lives. Implications for research on emotion beliefs and motivated emotion regulation are discussed.

Generation and Characterization of ORF55/ORF57-Deleted Recombinant Cyprinid herpesvirus 2 Mutants with Chimeric Capsid Protein Gene of Grouper Nervous Necrosis Virus.

Cyprinid herpesvirus 2 (CyHV-2) is a pathogen that causes significant losses to the global aquaculture industry due to mass mortality in crucian carp and goldfish. This study demonstrates that the ORF55/ORF57 deletion mutants CyHV-2-Δ55-CP and CyHV-2-Δ57-CP obtained through homologous recombination replicate effectively within the caudal fin of Carassius auratus gibelio (GiCF) cells and exhibit morphologies similar to the CyHV-2 wild-type strain. Both mutants demonstrated a decrease in virulence, with CyHV-2-Δ57-CP exhibiting a more significant reduction. This serves as a reference for the subsequent development of recombinant attenuated vaccines against CyHV-2. Additionally, both mutants expressed the inserted RGNNV-CP (capsid protein of Redspotted grouper nervous necrosis virus) fusion protein gene, and inoculation with CyHV-2-Δ57-CP-infected GiCF cell lysates elicited an antibody response in the grouper. These results indicate that, while ORF55 and ORF57 genes of CyHV-2 are not required for viral replication in vitro, they do play a role in virulence in vivo. Additionally, expression of foreign protein in CyHV-2 suggests that the fully attenuated mutant of CyHV-2 could potentially function as a viral vector for developing subunit vaccines or multivalent recombinant attenuated vaccines.

Chemokine CCL5 immune subtypes of human liver cancer with prognostic significance.

The immunogenicity of the liver tumor microenvironment is clinically heterogeneous and mysterious. The insight into the role of immune cells including tumor-infiltrating lymphocytes (TILs) and chemokine networks, might enable optimal patient selection for immunotherapy. In this study, we aimed at characterizing the liver cancer immune subtypes linked to chemokines and associating with the patient characteristics and clinical outcomes. We analyzed the immune cells and chemokine signatures of human liver cancer using GTEx and TCGA profiling of 110 normal liver tissues and 369 liver tumor patients. We performed hierarchical clustering to the chemokine expression by applying immune cells status to categorize the CCL5-related chemokine in liver tumors. The separation was characterized by dividing the liver tumor patients into CCL5-high and low subtypes. Our results showed that the high expression of myeloid-derived suppressor cells (MDSCs) is associated with a decrease in effector T cells expressing PRF1 in liver tumor progression. Our data demonstrated that the CCL5-high subtype significantly improved OS (p = 0.0379, hazard ratio (HR) 0.67; 95 % CI 0.43, 0.98), DFI (p = 0.0104, HR 0.63; 95 % CI 0.44, 0.90), PFI (p = 0.0066, HR 0.64; 95 % CI 0.46, 0.89) and working performance status. Our findings provide a novel perspective of liver cancer chemokine subtypes linked to immune cells. The therapy that can effectively activate effector T cells and inhibit MDSCs targeting chemokine networks might support the magnitude of TILs in liver tumors. The chemokine signatures in the CCL5-subtype are a valuable resource for future research to identify clinically relevant biomarkers.

An experimental model for ovarian cancer: propagation of ovarian cancer initiating cells and generation of ovarian cancer organoids.

BACKGROUND: Ovarian cancer (OC) is the most lethal gynecological cancer due to the recurrence of drug-resistance. Cancer initiating cells (CICs) are proposed to be responsible for the aggressiveness of OC. The rarity and difficulty of in vitro long-term cultivation of CICs challenge the development of CIC-targeting therapeutics. Reprogramming cancer cells into induced cancer initiating cell (iCICs) could be an approach to solve these. Several inducible CICs have been acquired by activating the expression of stemness genes in different cancer cells. However, few reports have demonstrated the feasibility in OC. METHODS: Patients with primary OC receiving surgery were enrolled. Tumor tissue were collected, and OCT4, SOX2, and NANOG expressions were assessed by immunohistochemistry (IHC) staining to investigate the association of stemness markers with overall survival (OS). An high-grade serous ovarian cancer (HGSOC) cell line, OVCAR-3 was reprogrammed by transducing Yamanaka four factors OCT4, SOX2, KLF4 and MYC (OSKM) to establish an iOCIC model, iOVCAR-3-OSKM. CIC characteristics of iOVCAR-3-OSKM were evaluated by RT-PCR, sphere formation assay and animal experiments. Drug-resistance and migration ability were accessed by dye-efflux activity assay, MTT assay and migration assay. Gene profile was presented through RNA-sequencing. Lineage differentiation ability and organoid culture were determined by in vitro differentiation assays. RESULTS: In OC patients, the co-expression of multiple stem-related transcription factors (OCT4, SOX2, and NANOG) was associated with worse OS. iOVCAR-3-OSKM cells generated by reprogramming successfully exhibited stemness characteristics with strong sphere-forming and tumorigenesis ability. iOVCAR-3-OSKM cells also showed malignant potential with higher drug resistance to chemodrug, Paclitaxel (PTX) and migration ability. iOVCAR-3-OSKM was maintainable and expandable on feeder-dependent culture condition, it also preserved ovarian lineage differentiation abilities, which could well differentiate into OC cells with CK-7 and CA125 expressions and develop into an organoid mimic poor prognostic OC histological feature. CONCLUSIONS: The establishment of iOVCAR-3-OSKM not only allows us to fill the gap in the information on induced CICs in OC but also provides a potential strategy to develop personalized CICs and organoid models for treating OC in the near future.

Rapid visual detection of Micropterus salmoides rhabdovirus using recombinase polymerase amplification combined with lateral flow dipsticks.

Largemouth bass (Micropterus salmoides) is an important freshwater-cultured species in China. Recently, a lethal and epidemic disease caused by Micropterus salmoides rhabdovirus (MSRV) results in huge economic losses to the largemouth bass industry. Current diagnostics for detecting MSRV are limited in sensitivity and speed and are inconvenient to be used for non-laboratory detection. In this study, three rapid and convenient detection assays of MSRV by recombinase polymerase amplification (RPA) and lateral flow dipsticks (LFD), targeting the conserved sequences of the MSRV-SS N gene, are described. With these RPA methods, the detection could achieve within 50 min at 38°C. Both methods of RPA-AGE and RPA-LFD could detect the viral DNA as low as 170 copies/µl of the MSRV standard plasmid and were 100-fold more sensitive than that in the method of routine PCR. Meanwhile, these RPA methods were highly specific for the detection of MSRV and can be feasibly applied to the diagnostic of MSRV infection. In brief, RPA-AGE, RPA-LFD and RT-RPA-LFD provide convenient, rapid, sensitive and reliable methods that could improve field diagnosis of MSRV with limited machine resources, and would enhance the production of largemouth bass.

Identification of unanimous immune subtypes for different hormone receptor phenotypes of human breast cancer with potential prognostic significance.

The immunogenicity of the breast tumor microenvironment is clinically heterogeneous. The insight into the role of tumor-infiltrating lymphocytes (TILs) might serve as a biomarker to predict a survival benefit and enable optimal patient selection for immunotherapy. In this study, we aimed at characterizing the breast cancer immune subtypes linked to CD8 T cells and associating with the patient characteristics and clinical outcomes. We analyzed the immune gene signatures of human breast cancer using The Genotype-Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) database profiling of 1092 breast tumor patients. We performed hierarchical clustering to the immune gene expression by applying hormone receptor status including triple negative breast cancer to categorize 66 immune-related genes in breast tumors. The separation was characterized by dividing the breast tumors into two major immune subtypes: predominant immune (PI) subtype and low immune subtype (LI). Our results showed that both PI and LI subtypes can be observed in the different hormone receptor phenotypes of breast tumors, and PI subtype accounted for 16% and LI subtype 20% in the breast tumor patients. The estimated odds for LI subtype breast tumors were significantly higher than PI subtype breast tumors in primary tumor stages. Our data demonstrated that the PI subtype breast tumors have significantly improved survival compared with LI subtype. Our findings provide a novel perspective of breast cancer immune subtypes linked to CD8 T cells. The immune subtypes will be a valuable resource for future research to identify clinically relevant biomarkers for precision immunotherapy.

Evaluation of inhibitors of intestinal UDP-glucuronosyltransferases 1A8 and 1A10 using raloxifene as a substrate in Caco-2 cells: Studies with four flavonoids of Scutellaria baicalensis.

UDP glucuronosyltransferases (UGTs) of the gastrointestinal tract play a crucial role in protection against the toxic effects of xenobiotics in the environment. UGTs such as UGT1A8 and UGT1A10 are predominantly expressed in gastrointestinal tissues. In this study, we examined the phase II metabolism of raloxifene in differentiated Caco-2 monolayers by inducing UGT1A8 and UGT1A10 expression in these cells. The present study evaluated the following four flavonoids of Scutellaria baicalensis as model herbal compounds: scutellarein, salvigenin, baicalein, and wogonin. All test compounds, endpoint substrates, and their metabolites were quantified using liquid chromatography and high-resolution mass spectrometry. The transepithelial electrical resistance values for the individual compounds were comparable regardless of whether they were measured individually. Salvigenin significantly inhibited UGT1A8 and UGT1A10 activities in a concentration-dependent manner. All individual compounds except scutellarein inhibited UGT1A8 and UGT1A10 activity at a concentration of 100 µM. In addition, all individual flavonoids at 100 µM, except wogonin, significantly increased the amount of raloxifene in the basolateral chambers. The positive control, canagliflozin, significantly inhibited both UGT1A8 and UGT1A10 activities. These findings suggest that the Caco-2 assay can be utilized for identifying UGT1A8 and UGT1A10 inhibitors and indicate the potential of salvigenin for enhancing the pharmacological effects of UGT substrate drugs.

Comparative global immune-related gene profiling of somatic cells, human pluripotent stem cells and their derivatives: implication for human lymphocyte proliferation.

Human pluripotent stem cells (hPSCs), including embryonic stem cells (ESCs) and induced PSCs (iPSCs), represent potentially unlimited cell sources for clinical applications. Previous studies have suggested that hPSCs may benefit from immune privilege and limited immunogenicity, as reflected by the reduced expression of major histocompatibility complex class-related molecules. Here we investigated the global immune-related gene expression profiles of human ESCs, hiPSCs and somatic cells and identified candidate immune-related genes that may alter their immunogenicity. The expression levels of global immune-related genes were determined by comparing undifferentiated and differentiated stem cells and three types of human somatic cells: dermal papilla cells, ovarian granulosa cells and foreskin fibroblast cells. We identified the differentially expressed genes CD24, GATA3, PROM1, THBS2, LY96, IFIT3, CXCR4, IL1R1, FGFR3, IDO1 and KDR, which overlapped with selected immune-related gene lists. In further analyses, mammalian target of rapamycin complex (mTOR) signaling was investigated in the differentiated stem cells following treatment with rapamycin and lentiviral transduction with specific short-hairpin RNAs. We found that the inhibition of mTOR signal pathways significantly downregulated the immunogenicity of differentiated stem cells. We also tested the immune responses induced in differentiated stem cells by mixed lymphocyte reactions. We found that CD24- and GATA3-deficient differentiated stem cells including neural lineage cells had limited abilities to activate human lymphocytes. By analyzing the transcriptome signature of immune-related genes, we observed a tendency of the hPSCs to differentiate toward an immune cell phenotype. Taken together, these data identify candidate immune-related genes that might constitute valuable targets for clinical applications.

Dual role of fatty acid-binding protein 5 on endothelial cell fate: a potential link between lipid metabolism and angiogenic responses.

Fatty acid-binding proteins (FABP) are small molecular mass intracellular lipid chaperones that are expressed in a tissue-specific manner with some overlaps. FABP4 and FABP5 share ~55 % amino acid sequence homology and demonstrate synergistic effects in regulation of metabolic and inflammatory responses in adipocytes and macrophages. Recent studies have shown that FABP4 and FABP5 are also co-expressed in a subset of endothelial cells (EC). FABP4, which has a primarily microvascular distribution, enhances angiogenic responses of ECs, including proliferation, migration, and survival. However, the vascular expression of FABP5 has not been well characterized, and the role of FABP5 in regulation of angiogenic responses in ECs has not been studied to date. Herein we report that while FABP4 and FABP5 are co-expressed in microvascular ECs in several tissues, FABP5 expression is also detected in ECs of larger blood vessels. In contrast to FABP4, EC-FABP5 levels are not induced by VEGF-A or bFGF. FABP5 deficiency leads to a profound impairment in EC proliferation and chemotactic migration. These effects are recapitulated in an ex vivo assay of angiogenesis, the aortic ring assay. Interestingly, in contrast to FABP4-deficient ECs, FABP5-deficient ECs are significantly more resistant to apoptotic cell death. The effect of FABP5 on EC proliferation and survival is mediated, only in part, by PPARδ-dependent pathways. Collectively, these findings demonstrate that EC-FABP5, similar to EC-FABP4, promotes angiogenic responses under certain conditions, but it can also exert opposing effects on EC survival as compared to EC-FABP4. Thus, the balance between FABP4 and FABP5 in ECs may be important in regulation of angiogenic versus quiescent phenotypes in blood vessels.

Fatty acid binding protein 4 deficiency protects against oxygen-induced retinopathy in mice.

Retinopathy of prematurity (ROP) is a leading cause of blindness in children worldwide due to increasing survival rates of premature infants. Initial suppression, followed by increased production of the retinal vascular endothelial growth factor-A (VEGF) expression are key events that trigger the pathological neovascularization in ROP. Fatty acid binding protein 4 (FABP4) is an intracellular lipid chaperone that is induced by VEGF in a subset of endothelial cells. FABP4 exhibits a pro-angiogenic function in cultured endothelial cells and in airway microvasculature, but whether it plays a role in modulation of retinal angiogenesis is not known. We hypothesized that FABP4 deficiency could ameliorate pathological retinal vascularization and investigated this hypothesis using a well-characterized mouse model of oxygen-induced retinopathy (OIR). We found that FABP4 was not expressed in retinal vessels, but was present in resident macrophages/microglial cells and endothelial cells of the hyaloid vasculature in the immature retina. While FABP4 expression was not required for normal development of retinal vessels, FABP4 expression was upregulated and localized to neovascular tufts in OIR. FABP4-/- mice demonstrated a significant decrease in neovessel formation as well as a significant improvement in physiological revascularization of the avascular retinal tissues. These alterations in retinal vasculature were accompanied by reduced endothelial cell proliferation, but no effect on apoptosis or macrophage/microglia recruitment. FABP4-/- OIR samples demonstrated decreased expression of genes involved in angiogenesis, such as Placental Growth Factor, and angiopoietin 2. Collectively, our findings suggest FABP4 as a potential target of pathologic retinal angiogenesis in proliferative retinopathies.

Fatty acid binding protein 4 regulates VEGF-induced airway angiogenesis and inflammation in a transgenic mouse model: implications for asthma.

Neovascularization of the airways occurs in several inflammatory lung diseases, including asthma. Vascular endothelial growth factor (VEGF) plays an important role in vascular remodeling in the asthmatic airways. Fatty acid binding protein 4 (FABP4 or aP2) is an intracellular lipid chaperone that is induced by VEGF in endothelial cells. FABP4 exhibits a proangiogenic function in vitro, but whether it plays a role in modulation of angiogenesis in vivo is not known. We hypothesized that FABP4 promotes VEGF-induced airway angiogenesis and investigated this hypothesis with the use of a transgenic mouse model with inducible overexpression of VEGF165 under a CC10 promoter [VEGF-TG (transgenic) mice]. We found a significant increase in FABP4 mRNA levels and density of FABP4-expressing vascular endothelial cells in mouse airways with VEGF overexpression. FABP4(-/-) mouse airways showed a significant decrease in neovessel formation and endothelial cell proliferation in response to VEGF overexpression. These alterations in airway vasculature were accompanied by attenuated expression of proinflammatory mediators. Furthermore, VEGF-TG/FABP4(-/-) mice showed markedly decreased expression of endothelial nitric oxide synthase, a well-known mediator of VEGF-induced responses, compared with VEGF-TG mice. Finally, the density of FABP4-immunoreactive vessels in endobronchial biopsy specimens was significantly higher in patients with asthma than in control subjects. Taken together, these data unravel FABP4 as a potential target of pathologic airway remodeling in asthma.

Endothelial cell-fatty acid binding protein 4 promotes angiogenesis: role of stem cell factor/c-kit pathway.

Fatty acid binding protein 4 (FABP4) plays an important role in regulation of glucose and lipid homeostasis as well as inflammation through its actions in adipocytes and macrophages. FABP4 is also expressed in a subset of endothelial cells, but its role in this cell type is not known. We found that FABP4-deficient human umbilical vein endothelial cells (HUVECs) demonstrate a markedly increased susceptibility to apoptosis as well as decreased migration and capillary network formation. Aortic rings from FABP4(-/-) mice demonstrated decreased angiogenic sprouting, which was recovered by reconstitution of FABP4. FABP4 was strongly regulated by mTORC1 and inhibited by Rapamycin. FABP4 modulated activation of several important signaling pathways in HUVECs, including downregulation of P38, eNOS, and stem cell factor (SCF)/c-kit signaling. Of these, the SCF/c-kit pathway was found to have a major role in attenuated angiogenic activity of FABP4-deficient ECs as provision of exogenous SCF resulted in a significant recovery in cell proliferation, survival, morphogenesis, and aortic ring sprouting. These data unravel a novel pro-angiogenic role for endothelial cell-FABP4 and suggest that it could be exploited as a potential target for diseases associated with pathological angiogenesis.

Sp1 acetylation is associated with loss of DNA binding at promoters associated with cell cycle arrest and cell death in a colon cell line.

Butyrate, a known histone deacetylase inhibitor (HDACi) and product of fibre fermentation, is postulated to mediate the protective effect of dietary fibre against colon cancer. The transcription factor Sp1 is a target of acetylation and is known to be associated with class I HDACs, including HDAC1. Sp1 is a ubiquitous transcription factor and Sp1-regulated genes include those involved in cell cycle regulation, apoptosis and lipogenesis: all major pathways in cancer development. The only known acetylated residue of Sp1 is lysine703 which resides in the DNA binding domain. Here we show that acetylated Sp1 loses p21- and bak-promoter -binding function in vitro. Furthermore treatment with a panel of HDAC inhibitors showed clustering of activities for a subset of inhibitors, causing G2 cell cycle arrest, Sp1 acetylation, p21 and Bak over-expression, all with very similar EC50 concentrations. These HDACi activities were not distributed according to the molecular class of compound. In order to mimic loss of binding, an siRNA strategy was used to reduce Sp1 expression. This resulted in altered expression of multiple elements of the p53/p21 pathway. Taken together our data suggest a mechanistic model for the chemopreventive actions of butyrate in colon epithelial cells, and provide new insight into the differential activities some classes of HDAC inhibitors.

Up-regulation of interleukin-17 expression by human papillomavirus type 16 E6 in nonsmall cell lung cancer.

BACKGROUND: Human papillomavirus (HPV) 16/18 infection is associated with nonsmoking lung cancer. In this study, the authors investigated a putative correlation between interleukin (IL)-17 expression and HPV infection in clinical nonsmall cell lung cancer (NSCLC) tissues and examined the effects of HPV infection on a human NSCLC cell line. METHODS: IL-17 expression was investigated in 79 NSCLC tumor tissues by immunohistochemistry. Growth rate, IL-17 mRNA, and secreting protein levels were also examined in HPV 16/18 E6-transfected H1299 human NSCLC cells. RESULTS: Immunohistochemical data showed that 48.1% of lung tumors had IL-17 staining, which was significantly associated with patients' sex (P = .03), HPV infection (P = .002), and tumor stage (P = .03). Significant correlations of IL-17 with IL-6 (P < .001) and IL-17 with Mcl-1 (P < .001) expression were also observed. Cell growth rate was increased, and IL-17/Mcl-1 expression levels were elevated in HPV 16 E6-transfected H1299 cells. The transfected E6 oncoproteins can significantly up-regulate expression levels of IL-17 and antiapoptotic protein Mcl-1. CONCLUSIONS: The study suggests that HPV infection-induced IL-17 levels can stimulate Mcl-1 expression through the PI3K pathway and promote lung tumor cell progression through a p53- and IL-6-independent pathway.

Spontaneous differentiation of adult rat marrow stromal cells in a long-term culture.

It is well recognized that bone marrow stromal cells (MSCs) can differentiate into neuron-like cells when supplemented with growth factors and/or chemical treatments. We demonstrated that primary MSCs obtained from adult rats could spontaneously differentiate into neural precursor cells after long-term culture. During the outset of in vitro culture, less than 0.1% of adult rat primary MSCs expressed nestin, the common protein of neural precursors. These MSCs didn't show neuronal morphology nor express neuronal antigens. In contrast, after continuous maintenance for 6 weeks, a significant subpopulation of MSCs formed cellular clumps and expressed nestin (32.3 +/- 6.3%). Less than 0.1% of cells expressing immature neuron marker betaIII-tubulin could be detected in these prolonged cultured MSCs. After serum deprivation and growth factor supplement, these nestin-positive cells could express neuron-like morphology and neuron-specific markers NF-H, betaIII-tubulin, tau, and neurotransmitter GABA. In contrast, the MSCs without prolonged culture didn't show neuronal morphology nor neuronal markers even after serum withdrawal and growth factors stimulation. These results demonstrated that neural precursors could be obtained from long-term cultured MSCs, and suggested that MSCs should be useful as a potential source for treatment of neurological disease.