Classification and clinical significance of immunogenic cell death-related genes in Plasmodium falciparum infection determined by integrated bioinformatics analysis and machine learning.

BACKGROUND: Immunogenic cell death (ICD) is a type of regulated cell death that plays a crucial role in activating the immune system in response to various stressors, including cancer cells and pathogens. However, the involvement of ICD in the human immune response against malaria remains to be defined. METHODS: In this study, data from Plasmodium falciparum infection cohorts, derived from cross-sectional studies, were analysed to identify ICD subtypes and their correlation with parasitaemia and immune responses. Using consensus clustering, ICD subtypes were identified, and their association with the immune landscape was assessed by employing ssGSEA. Differentially expressed genes (DEGs) analysis, functional enrichment, protein-protein interaction networks, and machine learning (least absolute shrinkage and selection operator (LASSO) regression and random forest) were used to identify ICD-associated hub genes linked with high parasitaemia. A nomogram visualizing these genes' correlation with parasitaemia levels was developed, and its performance was evaluated using receiver operating characteristic (ROC) curves. RESULTS: In the P. falciparum infection cohort, two ICD-associated subtypes were identified, with subtype 1 showing better adaptive immune responses and lower parasitaemia compared to subtype 2. DEGs analysis revealed upregulation of proliferative signalling pathways, T-cell receptor signalling pathways and T-cell activation and differentiation in subtype 1, while subtype 2 exhibited elevated cytokine signalling and inflammatory responses. PPI network construction and machine learning identified CD3E and FCGR1A as candidate hub genes. A constructed nomogram integrating these genes demonstrated significant classification performance of high parasitaemia, which was evidenced by AUC values ranging from 0.695 to 0.737 in the training set and 0.911 to 0.933 and 0.759 to 0.849 in two validation sets, respectively. Additionally, significant correlations between the expressions of these genes and the clinical manifestation of P. falciparum infection were observed. CONCLUSION: This study reveals the existence of two ICD subtypes in the human immune response against P. falciparum infection. Two ICD-associated candidate hub genes were identified, and a nomogram was constructed for the classification of high parasitaemia. This study can deepen the understanding of the human immune response to P. falciparum infection and provide new targets for the prevention and control of malaria.

Stomata variation in the process of polyploidization in Chinese chive (Allium tuberosum).

BACKGROUND: Stomatal variation, including guard cell (GC) density, size and chloroplast number, is often used to differentiate polyploids from diploids. However, few works have focused on stomatal variation with respect to polyploidization, especially for consecutively different ploidy levels within a plant species. For example, Allium tuberosum, which is mainly a tetraploid (2n = 4x = 32), is also found at other ploidy levels which have not been widely studied yet. RESULTS: We recently found cultivars with different ploidy levels, including those that are diploid (2n = 2x = 16), triploid (2n = 3x = 24), pseudopentaploid (2n = 34-42, mostly 40) and pseudohexaploid (2n = 44-50, mostly 48). GCs were evaluated for their density, size (length and width) and chloroplast number. There was no correspondence between ploidy level and stomatal density, in which anisopolyploids (approximately 57 and 53 stomata/mm2 in triploid and pseudopentaploid, respectively) had a higher stomatal density than isopolyploids (approximately 36, 43, and 44 stomata/mm2 in diploid, tetraploid and pseudohexaploid, respectively). There was a positive relationship between ploidy level and GC chloroplast number (approximately 44, 45, 51, 72 and 90 in diploid to pseudohexaploid, respectively). GC length and width also increased with ploidy level. However, the length increased approximately 1.22 times faster than the width during polyploidization. CONCLUSIONS: This study shows that GC size increased with increasing DNA content, but the rate of increase differed between length and width. In the process of polyploidization, plants evolved longer and narrower stomata with more chloroplasts in the GCs.

Cavernous hemangioma of the ileum in a young man: A case report and review of literature.

BACKGROUND: Small intestinal cavernous hemangioma is a rare disease, especially in the ileum. It is difficult to accurately diagnose due to its hidden location and nonspecific clinical symptoms. Here, we reported a case of ileal cavernous hemangioma with chronic hemorrhage in a 20-year-old man and review the literature to gain a better understanding of this disease. CASE SUMMARY: The patient complained of intermittent melena and hematochezia for > 3 mo. The lowest hemoglobin level revealed by laboratory testing was 3.4 g/dL (normal range: 12-16 g/dL). However, the gastroscopy, colonoscopy and peroral double-balloon enteroscopy (DBE) showed no signs of bleeding. The transanal DBE detected a lesion at about 340 cm proximal to the ileocecal valve. Thus, we performed an exploratory laparoscopy and the lesion was resected. After the operation, the patient had no melena. Finally, the pathological examination identified the neoplasm as an ileal cavernous hemangioma, thereby resulting in gastrointestinal hemorrhage. CONCLUSION: This report might improve the diagnosis and treatment of ileal cavernous hemangioma.

Cigarette smoke extract affects methylation status and attenuates Sca-1 expression of mouse endothelial progenitor cell in vitro.

INTRODUCTION: Endothelial dysfunction appears in many smoking-related diseases, it is also an important pathophysiological feature. Endothelial progenitor cells (EPCs) are precursors of endothelial cells and have a crucial effect on the repair and maintenance of endothelial integrity. Sca-1 is not only common in bone marrow-derived hematopoietic stem cells (HSCs), but it is also expressed in nonhematopoietic organs by tissue-resident stem and progenitor cells. The aim of this study is to investigate the impact of cigarette smoke extract (CSE) on the function of bone marrow-derived EPCs and the expression level of Sca-1 in EPCs, and also whether the methylation of Sca-1 is involved in EPC dysfunction. METHODS: We measured EPC capacities including adhesion, secretion and proliferation, the concentration of endothelial nitric oxide synthase (eNOS) and apoptosis-inducing factor (AIF) in cell culture supernatant, and also Sca-1 expression and promoter methylation in EPCs induced by CSE. Decitabine (Dec) was applied to test whether it could alter the impact caused by CSE. RESULTS: The adhesion, proliferation and secretion ability of EPCs can be induced to be decreased by CSE in vitro, accompanied by decreased concentrations of AIF and eNOS in cell culture supernatant and decreased Sca-1 expression in EPCs. In addition, Dec could partly attenuate the impact described above. There were no significant differences in the quantitative analysis of Sca-1 promoter methylation among different groups. CONCLUSIONS: The decreased Sca-1 expression was related to EPC dysfunction induced by CSE. EPC dysfunction resulting from CSE may be related to methylation mechanism, but not the methylation of Sca-1 promoter.

The role of MYB proto-oncogene like 2 in tamoxifen resistance in breast cancer.

Despite the efficacy of tamoxifen in preventing disease relapse, a large portion of breast cancer patients show intrinsic or acquired resistance to tamoxifen, leading to treatment failure and unfavorable clinical outcome. MYB proto-oncogene like 2 (MYBL2) is a transcription factor implicated in the initiation and progression of various human cancers. However, its role in tamoxifen resistance in breast cancer remained largely unknown. In the present study, by analyzing public transcriptome dataset, we found that MYBL2 is overexpressed in breast cancer and is associated with the poor prognosis of breast cancer patients. By establishing tamoxifen-resistant breast cancer cell lines, we also provided evidence that MYBL2 overexpression contributes to tamoxifen resistance by up-regulating its downstream transcriptional effectors involved in cell proliferation (PLK1, PRC1), survival (BIRC5) and metastasis (HMMR). In contrast, inhibiting those genes via MYBL2 depletion suppresses cancer progression, restores tamoxifen and eventually reduces the risk of disease recurrence. All these findings revealed a critical role of MYBL2 in promoting tamoxifen resistance and exacerbating the progression of breast cancer, which may serve as a novel therapeutic target to overcome drug resistance and improve the prognosis of breast cancer patients.

Association of tricellulin expression with poor colorectal cancer prognosis and metastasis.

Tricellulin is a tight­junction transmembrane protein that regulates cell­cell interactions. Altered tricellulin expression could promote tumor cell invasions and metastasis in human cancers. The present study assessed tricellulin expression in colorectal cancer tissues for any association with clinicopathological features of colorectal cancer patients and then investigated the underlying molecular events using quantitative proteomic analysis and in vitro experiments. Tissue samples from 98 colorectal cancer patients and 15 volunteers were collected for immunohistochemistry. Colorectal cell lines were used to overexpress or knockdown tricellulin expression in various assays. The data revealed that upregulated tricellulin expression was associated with lymph node and distant metastases and poor prognosis, while tricellulin overexpression promoted colorectal cancer cell migration and invasion in vitro. In contrast, tricellulin knockdown had positive effects on the tumor cells. Furthermore, TMT­LC­MS/MS and bioinformatics analyses revealed that tricellulin was involved in EMT and reduction of apoptosis through the NF­κB signaling pathway. These findings highlight for the first time the significance of tricellulin in colorectal cancer development and progression. Further study may validate tricellulin as a novel biomarker and target for colorectal cancer.

Mis-estimation of coronary lesions and rectification by SYNTAX score feedback for coronary revascularization appropriateness.

BACKGROUND: Imprecise interpretation of coronary angiograms was reported and resulted in inappropriate revascularization. Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score is a comprehensive system to evaluate the complexity of the overall lesions. We hypothesized that a real-time SYNTAX score feedback from image analysts may rectify the mis-estimation and improve revascularization appropriateness in patients with stable coronary artery disease (CAD). METHODS: In this single-center, historical control study, patients with stable CAD with coronary lesion stenosis ≥50% were consecutively recruited. During the control period, SYNTAX scores were calculated by treating cardiologists. During the intervention period, SYNTAX scores were calculated by image analysts immediately after coronary angiography and were provided to cardiologists in real-time to aid decision-making. The primary outcome was revascularization deemed inappropriate by Chinese appropriate use criteria for coronary revascularization. RESULTS: A total of 3245 patients were enrolled and assigned to the control group (08/2016-03/2017, n = 1525) or the intervention group (03/2017-09/2017, n = 1720). For SYNTAX score tertiles, 17.9% patients were overestimated and 4.3% were underestimated by cardiologists in the control group. After adjustment, inappropriate revascularization significantly decreased in the intervention group compared with the control group (adjusted odds ratio [OR]: 0.83; 95% confidence interval [CI]: 0.73-0.95; P = 0.007). Both inappropriate percutaneous coronary intervention (adjusted OR: 0.82; 95% CI: 0.74-0.92; P < 0.001) and percutaneous coronary intervention utilization (adjusted OR: 0.88; 95% CI: 0.79-0.98; P = 0.016) decreased significantly in the intervention group. There was no significant difference in 1-year adverse cardiac events between the control group and the intervention group. CONCLUSIONS: Real-time SYNTAX score feedback significantly reduced inappropriate coronary revascularization in stable patients with CAD. CLINICAL TRIAL REGISTRATION: Nos. NCT03068858 and NCT02880605; https://www.clinicaltrials.gov.

Tumor necrosis factor-like weak inducer of apoptosis regulates quadriceps muscle atrophy and fiber-type alteration in a rat model of chronic obstructive pulmonary disease.

BACKGROUND: In chronic obstructive pulmonary disease (COPD), weakness and muscle mass loss of the quadriceps muscle has been demonstrated to predict survival and mortality rates of patients. Tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK), as a member of the TNF superfamily, has recently been identified as a key regulator of skeletal muscle wasting and metabolic dysfunction. So our aim was to study the role of TWEAK during quadriceps muscle atrophy and fiber-type transformation in COPD model rats and its possible pathway. METHODS: Forty-four healthy male adult Wistar rats were randomly divided into two groups: A normal control group (n = 16) and a COPD model group (n = 28). The COPD group was exposed to cigarette smoke for 90 d and injected with porcine pancreatic elastase on day 15, whereas the control group was injected with saline alone. Following treatment, weights of the quadriceps muscles were measured and hematoxylin and eosin staining was performed to identify structural changes in lung and quadriceps muscle tissue. Immunohistochemical staining was also conducted to determine the localization of TWEAK, nuclear factor (NF)-κB, muscle ring finger (MuRF)-1 and proliferator-activated coactivator (PGC)-1a proteins in the quadriceps muscle, and western blotting was used to assess the level of protein expression. RESULTS: Compared with controls, COPD model rats exhibited significantly lower quadriceps muscle weight (P < 0.05) accompanied by fiber atrophy and disordered fiber arrangement, a wide gap between adjacent muscle fibers, a significant reduction in nuclear number (P < 0.05) and an uneven size distribution. The proportion of fiber types was also significantly altered (P < 0.05). In addition, TWEAK expression in the quadriceps muscle of COPD model rats was significantly higher than that in control rats (P < 0.05), and was significantly associated with quadriceps atrophy and fiber-type alteration (P < 0.05). Levels of NF-κB, MuRF1 and PGC-1α expression also significantly differed between the two groups (P < 0.05). CONCLUSIONS: Collectively these data suggest that increased levels of TWEAK may lead to skeletal muscle atrophy and fiber-type alteration, which in turn may be associated with activation of the ubiquitin-proteasome pathway, involving NF-κB, MuRF1 and PGC-1α as potential regulatory factors. These preliminary results in rats suggest that TWEAK may be a therapeutic target for the treatment of muscle atrophy in COPD.

Mechanisms of an increased level of serum iron in gamma-irradiated mice.

The potential mechanisms underlying the increase in serum iron concentration in gamma-irradiated mice were studied. The gamma irradiation dose used was 4 Gy, and cobalt-60 ((60)Co) source was used for the irradiation. The dose rate was 0.25 Gy/min. In the serum of irradiated mice, the concentration of ferrous ions decreased, whereas the serum iron concentration increased. The concentration of ferrous ions in irradiated mice returned to normal at 21 day post-exposure. The concentration of reactive oxygen species in irradiated mice increased immediately following irradiation but returned to normal at 7 day post-exposure. Serum iron concentration in gamma-irradiated mice that were pretreated with reduced glutathione was significant lower (p < 0.01) than that in mice exposed to gamma radiation only. However, the serum iron concentration was still higher than that in normal mice (p < 0.01). This change was biphasic, characterized by a maximal decrease phase occurring immediately after gamma irradiation (relative to the irradiated mice) and a recovery plateau observed during the 7th and 21st day post-irradiation, but serum iron recovery was still less than that in the gamma-irradiated mice (4 Gy). In gamma-irradiated mice, ceruloplasmin activity increased and serum copper concentration decreased immediately after irradiation, and both of them were constant during the 7th and 21st day post-irradiation. It was concluded that ferrous ions in irradiated mice were oxidized to ferric ions by ionizing radiation. Free radicals induced by gamma radiation and ceruloplasmin mutually participated in this oxidation process. The ferroxidase effect of ceruloplasmin was achieved by transfer of electrons from ferrous ions to cupric ions.

Enhancement of radiotherapy by ceria nanoparticles modified with neogambogic acid in breast cancer cells.

Radiotherapy is one of the main strategies for cancer treatment but has significant challenges, such as cancer cell resistance and radiation damage to normal tissue. Radiosensitizers that selectively increase the susceptibility of cancer cells to radiation can enhance the effectiveness of radiotherapy. We report here the development of a novel radiosensitizer consisting of monodispersed ceria nanoparticles (CNPs) covered with the anticancer drug neogambogic acid (NGA-CNPs). These were used in conjunction with radiation in MCF-7 breast cancer cells, and the efficacy and mechanisms of action of this combined treatment approach were evaluated. NGA-CNPs potentiated the toxic effects of radiation, leading to a higher rate of cell death than either treatment used alone and inducing the activation of autophagy and cell cycle arrest at the G2/M phase, while pretreatment with NGA or CNPs did not improve the rate of radiation-induced cancer cells death. However, NGA-CNPs decreased both endogenous and radiation-induced reactive oxygen species formation, unlike other nanomaterials. These results suggest that the adjunctive use of NGA-CNPs can increase the effectiveness of radiotherapy in breast cancer treatment by lowering the radiation doses required to kill cancer cells and thereby minimizing collateral damage to healthy adjacent tissue.

[Effects of PPAR-gamma agonist rosiglitazone on MMP-9 and TIMP-1 expression of monocyte-derived macrophages isolated from patients with acute coronary syndrome].

OBJECTIVE: Coronary arterial plaque rupture and secondary thrombosis are the major pathogenesis of acute coronary syndrome (ACS). Metalloprotease (MMPs) secreted by monocyte/macrophage was the main predisposing factor of the plaque rupture and peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is involved in a variety of inflammatory cytokine gene transcriptional regulations. We explored the possible role of PPAR-gamma in the regulation of MMP-9 and TIMP-1 expressed by peripheral monocyte-derived macrophages (MDMs) from patients with ACS. METHODS: Peripheral blood mononuclear cells were isolated from 48 patients with ACS and 28 healthy controls and stimulated by macrophage colony-stimulating factor (0.1 microg/ml for 24 hours) to form MDMs. MDMs were then incubated under various concentrations of rosiglitazone (0, 1, 10, 20 micromol/L) for 48 hours. The concentrations of MMP-9 and TIMP-1 in the supernatant were measured by enzyme linked immunosorbent assay, and the mRNA expression of PPAR-gamma, MMP-9 by RT-PCR and nuclear factor-kappaB P65 (NF-kappaB P65) expression by immunohistochemistry. RESULTS: PPAR-gamma mRNA expression was significantly lower while NF-kappaB P65 and MMP-9 expression as well as MMP-9 and TIMP-1 concentrations in supernatant were significantly higher in ACS group than those in control group (all P < 0.05). After rosiglitazone intervention, PPAR-gamma mRNA expression was significantly upregulated in both ACS and control groups in a dose-dependent manner. Both the MMP-9 concentration in the supernatant and MMP-9 mRNA expression were reduced post intervention with rosiglitazone in both groups. The TIMP-1 mRNA expression and concentration in supernatant were not affected by rosiglitazone in both groups. Rosiglitazone induced significant downregulation of NF-kappaB P65 expression in both groups. CONCLUSION: Rosiglitazone intervention may downregulate MMP-9 expression by upregulating PPAR-gamma expression, and by downregulating NF-kappaB expression in MDMs isolated from patients with ACS.

In vivo anti-tumor effect of hybrid vaccine of dendritic cells and esophageal carcinoma cells on esophageal carcinoma cell line 109 in mice with severe combined immune deficiency.

AIM: To develop a fusion vaccine of esophageal carcinoma cells and dendritic cells (DC) and observe its protective and therapeutic effect against esophageal carcinoma cell line 109 (EC109). METHODS: The fusion vaccine was produced by fusing traditional polyethyleneglycol (PEG), inducing cytokine, sorting CD34+ magnetic microbead marker and magnetic cell system (MACS). The liver, spleen and lung were pathologically tested after injection of the fusion vaccine. To study the therapeutic and protective effect of the fusion vaccine against tumor EC109, mice were divided immune group and therapeutic group. The immune group was divided into P, E, D and ED subgroups, immunized by phosphate buffered solution (PBS), inactivated EC109, DC and the fusion vaccine respectively, and attacked by EC109 cells. The tumor size, weight, latent period and mouse survival period were recorded and statistically analyzed. The therapeutic group was divided into four subgroups: P, inactivated EC109, D and ED subgroups, which were attacked by EC109 and then treated with PBS, inactivated EC109, DC, and EC109-DC respectively. Pathology and flow cytometry were also used to study the therapeutic effect of the fusion vaccine against EC109 cells. RESULTS: Flow cytometry showed that the expression of folate receptor (FR), EC109 (C), DCs (D) in human nasopharyngeal carcinoma cell line (HNE1) (B) was 78.21%, 89.50%, and 0.18%, respectively. The fusion cells (C) were highly expressed. No tumor was found in the spleen, lung and liver after injection of the fusion vaccine. Human IgG was tested in peripheral blood lymphocytes (PBL). In the immune group, the latent period was longer in EC109-DC subgroup than in other subgroups, while the tumor size and weight were also smaller than those in ED subgroup. In the therapeutic group, the tumor size and weight were smaller in ED subgroup than in P, inactivated EC109 and DC subgroups. CONCLUSION: Fusion cells are highly expressed not only in FR but also in CD80. The fusion vaccine has a distinctive protective effect against tumor EC109 and can inhibit the growth of tumor in mice, and its immune protection against tumor attack is more significant.

Activation of cytotoxic T lymphocytes against CML28-bearing tumors by dendritic cells transduced with a recombinant adeno-associated virus encoding the CML28 gene.

Induction of anti-tumor immune responses by dendritic cells (DCs) transduced with a recombinant adeno-associated virus type 2 (rAAV2) encoding tumor antigens is considered a promising approach for cancer vaccine development. CML28, a novel antigen with the properties of cancer/ testis (CT) antigens, is an attractive target for antigen-specific immunotherapy. Here we investigated the feasibility of inducing CML28-specific cytotoxic T lymphocyte (CTL) responses using DCs transduced with the rAAV2 vectors containing the CML28 gene (rAAV/CML28). Using an adenovirus-free packaging system, rAAV/CML28 was generated. The transduction efficiency of rAAV/CML28 in DCs increased in a multiplicity of infection (MOI)-dependent manner. The rAAV/CML28 transduction did not impair DC maturation, but even enhanced the CD80 expression. The rAAV/CML28-transduced DCs induced CML28-specific CTLs which exhibited a MHC class I-mediated antigen-specific lytic activity against CML28-bearing tumor cell lines (HepG2 and MCF-7) as well as the primary leukemia blasts. These findings suggest that rAAV/CML28-transduced DCs vaccine may serve as a feasible approach for the treatment of CML28-associated cancers.

[Determination of chemical components in tobacco leaves by FT-NIR spectroscopy: study of influence of spectral ranges on PLS modeling].

NIR spectra of tobacco leaves were measured in the range of 12000 to 4000 cm(-1) using a Bruker MPA FT-NIR spectrometer. PLS calibration models were developed and optimized for rapid quantitative analysis of nicotine alkaloids, total sugar and total nitrogen contents in tobacco leaves. It was found that the prediction errors of the same component were significantly different when different spectral regions were used for PLS modeling, and the best spectral range is also different for each component. The study demonstrated that wavelength range selection is one of the important keys to optimizing the NIR calibration model. In this study it was found that the optimized calibration ranges for nicotine alkaloids, total sugar and total nitrogen are 9500-4231.2 cm(-1), 7502.1-4246.7 cm(-1) and 7502.1-4597.7 cm(-1), respectively. The Root Mean Square Error of Cross Validation (RMSECV) of the three calibration models are 0.081 5, 0.808 and 0.056, respectively.

Biotransformation of pinoresinol diglucoside to mammalian lignans by human intestinal microflora, and isolation of Enterococcus faecalis strain PDG-1 responsible for the transformation of (+)-pinoresinol to (+)-lariciresinol.

By anaerobic incubation of pinoresinol diglucoside (1) from the bark of Eucommia ulmoides with a fecal suspension of humans, eleven metabolites were formed, and their structures were identified as (+)-pinoresinol (2), (+)-lariciresinol (3), 3'-demethyl-(+)-lariciresinol (4), (-)-secoisolariciresinol (5), (-)-3-(3", 4"-dihydroxybenzyl)-2-(4'-hydroxy-3'-methoxybenzyl)butane-1, 4-diol (6), 2-(3', 4'-dihydroxybenzyl)-3-(3", 4"-dihydroxybenzyl)butane-1, 4-diol (7), 3-(3"-hydroxybenzyl)-2-(4'-hydroxy-3'-methoxybenzyl)butane-1, 4-diol (8), 2-(3', 4'-dihydroxybenzyl)-3-(3"-hydroxybenzyl)butane-1, 4-diol (9), (-)-enterodiol (10), (-)-(2R, 3R)-3-(3", 4"-dihydroxybenzyl)-2-(4'-hydroxy-3'-methoxybenzyl)butyrolactone (11), (-)-(2R, 3R)-2-(3', 4'-dihydroxybenzyl)-3-(3", 4"-dihydroxybenzyl)butyrolactone (12), (-)-(2R, 3R)-3-(3"-hydroxybenzyl)-2-(4'-hydroxy-3'-methoxybenzyl)butyrolactone (13), 2-(3', 4'-dihydroxybenzyl)-3-(3"-hydroxybenzyl)butyrolactone (14), 2-(3'-hydroxybenzyl)-3-(3", 4"-dihydroxybenzyl)butyrolactone (15) and (-)-(2R, 3R)-enterolactone (16) by various spectroscopic means, including two dimensional (2D)-NMR, mass spectrometry and circular dichroism. A possible metabolic pathway was proposed on the basis of their structures and time course experiments monitored by thin-layer chromatography. Furthermore, a bacterial strain responsible for the transformation of (+)-pinoresinol to (+)-lariciresinol was isolated from a human fecal suspension and identified as Enterococcus faecalis strain PDG-1.

Transformation of arctiin to estrogenic and antiestrogenic substances by human intestinal bacteria.

After anaerobic incubation of arctiin (1) from the seeds of Arctium lappa with a human fecal suspension, six metabolites were formed, and their structures were identified as (-)-arctigenin (2), (2R,3R)-2-(3',4'-dihydroxybenzyl)-3-(3",4"-dimethoxybenzyl)butyrolactone (3), (2R,3R)-2-(3'-hydroxybenzyl)-3-(3",4"-dimethoxybenzyl)butyrolactone (4), (2R,3R)-2-(3'-hydroxybenzyl)-3-(3"-hydroxy-4"-methoxybenzyl)butyrolactone (5), (2R,3R)-2-(3'-hydroxybenzyl)-3-(3",4"-dihydroxybenzyl)butyrolactone (6), and (-)-enterolactone (7) by various spectroscopic means including two dimensional (2D)-NMR, mass spectrometry, and circular dichroism. A possible metabolic pathway was proposed on the basis of their structures and the time course of the transformation. Enterolactones obtained from the biotransformation of arctiin and secoisolariciresinol diglucoside (SDG, from the seeds of Linum usitatissium) by human intestinal bacteria were proved to be enantiomers, with the (-)-(2R,3R) and (+)-(2S,3S) configurations, respectively. Compound 6 showed the most potent proliferative effect on the growth of MCF-7 human breast cancer cells in culture among 1 and six metabolites, while it showed inhibitory activity on estradiol-mediated proliferation of MCF-7 cells at a concentration of 10 microM. These results indicate that the transformation of 1 by intestinal flora might be essential for the manifestation of the estrogenic and antiestrogenic activity of 1.

[Generation of Dendritic Cells from Human Cord Blood CD34(+) Cells and Their Activation of T Cell-Dependent Antitumor Immune Response In Vitro]

To induce the growth and differentiation of dendritic cells (DCs) from human cord blood, CD34(+) cells isolated from human cord blood by mini-MACS were cultured in a liquid culture system with rhSCF, rhGM-CSF, rhTNF-alpha and rhFL for 10 days. Then the induced cells were characterized by DC's morphological and phenotypic properties. In addition, they stimulated the proliferation of allogeneic T cells and possessed an efficient capacity for initiating T cell-dependent antitumor immune responses in vitro. It is concluded that mature DCs could be obtained from human cord blood CD34(+) cells.