Cross-waveband optical computing imaging.

A novel, to the best of our knowledge, cross-spectral optical computing imaging experiment has been achieved through a single exposure of a charge-coupled device. The experimental setup integrates single-pixel imaging (SPI) with ghost imaging (GI) through a photoelectric conversion circuit and a synchronous modulation system. The experimental process involves modulation in one wavelength band (in SPI) and demodulation using the GI algorithm in another. Significantly, our approach utilizes optical computing demodulation, a departure from the conventional electronic demodulation in GI (SPI), which involves the convolution between the bucket optical signals and the modulated patterns on the digital micromirror device. A proof-of-concept cross-band imaging experiment from near-infrared to visible light has been carried out. The results highlight the system's ability to capture images at up to 20 frames per second using near-infrared illumination, which are then reconstructed in the visible light spectrum. This success not only validates the feasibility of our approach but also expands the potential applications in the SPI or GI fields, particularly in scenarios where two-dimensional detector arrays are either unavailable or prohibitively expensive in certain electromagnetic spectra such as x-ray and terahertz.

Two-Phase Electrosynthesis of Dihydroxycoumestans: Discovery of a New Scaffold for Topoisomerase I Poison.

Coumestan represents a biologically relevant structural motif distributed in a number of natural products, and the rapid construction of related derivatives as well as the characterization of targets would accelerate lead compound discovery in medicinal chemistry. In this work, a general and scalable approach to 8,9-dihydroxycoumestans via two-electrode constant current electrolysis was developed. The application of a two-phase (aqueous/organic) system plays a crucial role for success, protecting the sensitive o-benzoquinone intermediates from over-oxidation. Based on the structurally diverse products, a primary SAR study on coumestan scaffold was completed, and compound 3 r exhibited potent antiproliferative activities and a robust topoisomerase I (Top1) inhibitory activity. Further mechanism studies demonstrates that compound 3 r was a novel Top1 poison, which might open an avenue for the development of Top1-targeted antitumor agent.

Electrochemical Synthesis of Phenothiazinone as Fluorophore and Its Application in Bioimaging.

Phenothiazinone is a promising yet underutilized fluorophore, possibly due to the lack of a general accessibility. This study reports a robust and scalable TEMPO-mediated electrochemical method to access a variety of phenothiazinones from 2-aminothiophenols and quinones. The electrosynthesis proceeds in a simple cell architecture under mild condition, and notably carbon-halogen bond in quinones remains compared to conventional methods, enabling orthogonal downstream functionalization. Mechanistic studies corroborate that TEMPO exerts a protective effect in avoiding product decomposition at the cathode. In particular, benzophenothiazinones show intriguing luminescence in both solid and solution state, and thus their photophysical properties are scrutinized in detail. Further bio-imaging of the lipid droplets in living cells highlights the considerable promise of benzophenothiazinones as fluorescent dye in the biomedical fields.

ß-Catenin-treated peptides effectively inhibit the proliferation of colorectal cancer.

To verify the inhibitory mechanism of ß-catenin-designed peptides in colorectal cancer(CRC) tumors, the following experiments were performed. In vitro colony formation, Transwell assays, and flow cytometry were performed to assess the biological effects of designed peptides (F18KD, F20A4-7k, F20A4-10k, and F20A3-9k + F20A4-10k + F20A5-9k) in HT-29 cells. In vivo xenograft experiments were performed and treated with peptides. Next, tumors were subjected to Hematoxylin and eosin staining (HE), immunohistochemical, and terminal deoxynucleotidyl transferase dUTP nick end labeling staining assays to evaluate the inhibitory effect of peptides on tumors. ß-Catenin levels were quantified via western blotting (WB) and quantitative real-time polymerase chain reaction, and ß-catenin was located using confocal laser scanning microscopy. T-cell factor-4 (TCF-4), C-myc, and CCND1 levels were quantified via WB. Results were obtained as following. First, the peptides reduced viability, migration, and invasion; promoted apoptosis; and stabilized the S phase of HT-29 cells. Second, peptides suppressed tumor growth and downregulated the expression of CD34, vascular endothelial growth factor, and ß-catenin in tumors. Furthermore, we found that peptides downregulated ß-catenin expression in both the cytoplasm and nucleus; TCF-4, C-myc, and CCND1 expression was also downregulated. Notably, ß-catenin-targeting peptides had a better inhibitory effect on CRC than non-ß-catenin-target peptides, and a combination of peptides exerted a more potent inhibitory effect on CRC than single peptides. It suggested that ß-Catenin-targeting peptides promote apoptosis in CRC tumors by inhibiting activation of the Wnt/ß-catenin pathway.

Three important short-chain fatty acids (SCFAs) attenuate the inflammatory response induced by 5-FU and maintain the integrity of intestinal mucosal tight junction.

BACKGROUND: 5-Fluorouracil (5-FU) is a used chemotherapy drug for cancer, and its main side effect is intestinal mucositis which causes chemotherapy to fail. It was known that short-chain fatty acids (SCFAs) can inhibit immune cell release of various proinflammatory factors and inhibit excessive intestinal inflammation. However, the inhibitory effect of SCFAs on 5-FU-induced intestinal mucositis is still unclear. RESULTS: To simulate the effects of SCFAs on immune and intestinal epithelial cells, the cells (THP-1 cells and Caco-2 cells) were pretreated with sodium acetate (NaAc), sodium propionate (NaPc) and sodium butyrate (NaB), then inflammation was induced by 5-FU. The expressions of reactive oxygen species (ROS), Beclin-1, LC3-II, NF-κB p65, NLRP3 inflammasome, proinflammatory/anti-inflammatory cytokines and mucosal tight junction proteins were determined. In our results, the three SCFAs could inhibit ROS expressions, NLRP3, Caspase-1, IL-1ß, IL-6, IL-18, Beclin-1 and LC3-II, when induced by 5-FU. In a 5-FU-induced chemoentermuctis mouse model, Lactobacillus rhamnoides can increase the concentrations of three SCFAs in faeces and increase the concentrations of IL-1ß, IL-6 and IgA in serum, and decrease the expressions of NLRP3 and IL-17 in spleen cells. The expressions of ZO-1 and Occludin in intestinal mucosa were significantly increased. CONCLUSIONS: These results indicated that the three SCFAs can effectively suppress the inflammation of THP-1 cells and Caco-2 cells and maintain tight junction integrity in intestinal mucosal epithelial cells.

New C9 -Monoterpenoid Alkaloids Featuring a Rare Skeleton with Anti-Inflammatory and Antiviral Activities from Forsythia suspensa.

Forsyqinlingines C (1) and D (2), two C9 -monoterpenoid alkaloids bearing a rare skeleton, were isolated from the ripe fruits of Forsythia suspensa. Their structures, including absolute configurations, were fully elucidated by extensive spectroscopic data and ECD experiments. The plausible biogenetic pathway for compounds 1 and 2 was also proposed. In vitro, two C9 -monoterpenoid alkaloids showed anti-inflammatory activity performed by the inhibitory effect on the release of ß-glucuronidase in rat polymorphonuclear leukocytes (PMNs), as well as antiviral activity against influenza A (H1N1) virus and respiratory syncytial virus (RSV).

Three main short-chain fatty acids inhibit the activation of THP-1 cells by Mycoplasma pneumoniae.

The overactivation of macrophages causes chronic inflammatory diseases. Short-chain fatty acids (SCFAs), potential drugs for clinical treatment, are modulators of macrophage inflammatory reaction. Therefore, the modulation of macrophage-mediated cell activity is expected to become a new therapeutic strategy for inflammatory diseases caused by Mycoplasma pneumoniae. In this study, 2 kinds of SCFAs (propionate and butyrate) were found to have anti-inflammatory effects in M. pneumoniae-stimulated THP-1 cells inflammatory. They inhibited the expressions of IL-4, IL-6, ROS, and NLRP3 inflammasome, while enhancing the expressions of IL-10 and IFN-γ. Our study revealed these 2 agents to repress transcriptional activities of NF-κB, which are important modulators of inflammation. Meanwhile, SCFAs can significantly enhance the autophagy induced by M. pneumoniae. Considering that SCFAs have few side effects, they might be the promising adjuvant therapy for the prevention and/or treatment of various inflammatory diseases.

Association of Thiamine Intake with Human Papillomavirus (HPV) Infection in American Women: A Secondary Data Analysis Based on the National Health and Nutrition Examination Survey from 2003 to 2016.

BACKGROUND Studies have shown that thiamine intake is associated with cervical cancer, but the relationship between thiamine and HPV infection remains unclear. In the present study, we used the National Health and Nutrition Examination Survey (NHANES) database to investigate whether HPV infection was associated with thiamine intake. MATERIAL AND METHODS A total of 13 471 women ages 18-59 years were selected from the NHANES database from 2003 to 2016. Using thiamine intake as the independent variable, HPV infection as the dependent variable, and sociodemographic data and other data as the covariates, we analyzed the relationship between thiamine and HPV infection by conducting a weighted logistic regression model in a cross-sectional research design. RESULTS The two-piecewise linear model indicated the inflection point of thiamine intake was 2.07 mg. On the left side of the inflection point, the difference in the thiamine intake of log2 conversion was related to the difference of 0.82 in HPV infection, which means that the increase of every 1 unit increase in thiamine intake is associated with the decrease of the HPV infection by 18%. On the right side of the inflection point, we did not observe a correlation between HPV infection and thiamine intake. CONCLUSIONS Thiamine intake is negatively correlated with HPV infection. Intake of an appropriate amount of thiamine can prevent HPV infection. The best preventive effect can be achieved when the intake is about 2 mg, and excessive intake will not increase the preventive effect.

Altered intrinsic brain activity and regional cerebral blood flow in patients with chronic neck and shoulder pain.

PURPOSE: To identify the changes of intrinsic brain activity and regional cerebral blood flow in patients with chronic neck and shoulder pain (CNSP) by using amplitude of low-frequency fluctuation (ALFF) analysis and arterial spin labelling study. MATERIAL AND METHODS: In total, 28 CNSP patients and 25 age-matched and sex-matched healthy controls (HCs) participated in the study. Resting-state functional magnetic resonance imaging (rs-fMRI) and arterial spin labelling (ASL) MRI were acquired. Correlations between ALFF and cerebral blood flow (CBF) were analysed. Subsequently, the differences in ALFF and CBF were compared in the two groups. Finally, the visual analogue scale (VAS) was also assessed in the CNSP group. RESULTS: Compared with HCs, CNSP patients showed significantly abnormal ALFF and CBF in several brain regions, including the cerebellum posterior lobe, middle orbitofrontal gyrus, medial superior frontal gyrus, middle temporal gyrus, precuneus, cingulate gyrus, middle occipital gyrus, middle frontal gyrus, postcentral gyrus, precentral gyrus, and superior parietal gyrus. Correlation analysis showed that the ALFF value of the medial superior frontal gyrus positively correlated with the VAS score. However, no correlation was found between the CBF values and the VAS score. CONCLUSIONS: The altered ALFF and CBF values in CNSP patients were observed in different pain-related brain regions that were involved in pain modulation and perception. The combination of rs-fMRI and ASL MRI might provide complementary information for increasing our understanding of the neuropathology in CNSP.

[Clinical application evaluation of Guidelines for the Diagnosis and Treatment of Common Diseases of Pediatrics in Traditional Chinese Medicine].

Clinical application evaluation research of Guidelines for the Diagnosis and Treatment of Common Diseases of Pediatrics in Traditional Chinese Medicine intends to evaluate the quality level and clinical application of the guideline. A questionnaire and prospective case survey methods were used to evaluate the applicability evaluation based on the clinician questionnaire and the application evaluation based on clinical case observation. The applicability evaluation, familiarity and utilization rate of doctors' guidelines were 85.06%, 62.76%; Sort by technical grade, intermediate grade doctors have a higher familiarity rate and utilization rate, while the junior grade doctor's is lower; Guide quality level of applicability evaluation, other items' rational percentage are better than 96% except the items of health preserving and prevention and other treatment is relatively low; Items' applicable percentage of applicability evaluation are more than 91% except the item of guide simplicity. Comprehensive applicability evaluation, The percentage of the guideline applicable to clinical practice accounted for 94.94%. The consistency rate of syndrome differentiation and clinical application is more than 96% in addition to prescription medication, other treatments and health preserving and prevention of the guidelines apply consistency of application evaluation. The percentage of good treatment effect accounted for 92.96% of application effect evaluation. The safety percentage is 99.89% and economy is 97.45%. The research shows that of Guidelines for the Diagnosis and Treatment of Common Diseases of Pediatrics in Traditional Chinese Medicine quality level is good and is basically applicable to pediatric clinical practice which can be used as a standardized recommendation of pediatric common diseases' treatment specification. A small part of the guidelines are not applicable and need to be further consummated. Health preserving and prevention and other treatment of the guideline need to be revised.

[Clinical application evaluation of Guidelines for Diagnosis and Treatment of Common Diseases of Otolaryngology in Traditional Chinese Medicine].

This study is to assess the Guidelines for Diagnosis and Treatment of Common Diseases of Otolaryngology in Traditional Chinese Medicine in clinical application and provide evidence for further guideline revision. The assessment was divided into applicability assessment and practicability assessment. The applicability assessment based on questionnaire survey and the traditional Chinese medicine (TCM) practitioners were asked to independently fill the Questionnaire for Applicability Assessment on the Guidelines for Diagnosis and Treatment in Traditional Chinese Medicine. The practicability assessment was based on prospective case investigation and analysis method and the TCM practitioners-in-charge filled the Case Investigation Questionnaire for Practicability Assessment on the Guidelines for Diagnosis and Treatment in Traditional Chinese Medicine. The data were analyzed in descriptive statistics. 151 questionnaires were investigated for applicability assessment and 1 016 patients were included for practicability assessment. The results showed that 88.74% of them were familiar with the guidelines and 45.70% used them. The guidelines quality and related items were similar in applicability assessment and practicability assessment, and scored highly as more than 85.00% except the "recuperating and prevention". The results suggested that the quality of Guidelines for Diagnosis and Treatment of Common Diseases of Otolaryngology in Traditional Chinese Medicine was high and could better guide the clinical practice. The "recuperating and prevention" part should be improved and the evidence data should be included in future guideline revision, so that the clinical utilization rate could be increased.

[Clinical application evaluation of Guidelines for Diagnosis and Treatment of Common Diseases of Coloproctology in Traditional Chinese Medicine].

To provide reference for revising the Guidelines for Diagnosis and Treatment of Common Diseases of Coloproctology in Traditional Chinese Medicine (TCM) through clinical research. 9 TCM hospitals worldwide have conducted a survey and questionnaires for 7 CPGs have been received. 263 cases clinical doctors accepted the applicability survey of guidelines. 89.35% is more familiar to the guidelines and 36.12% have been used the guidelines. In syndrome differentiation and treatment related contents, diagnostic point, treatment and syndrome differentiation are higher, accounted for 96.96%, 88.59%, 96.20%, respectively. Rationality of prevention is lower, accounted for 65.02%.88.21% clinical doctors believe that the Guidelines for Diagnosis and Treatment of Common Diseases of Coloproctology in Traditional Chinese Medicine is applicable. The application of the guidelines is evaluated by prospective observation of 1 309 cases. The higher consistency between guidelines and clinical practice is Western medicine disease diagnosis and traditional Chinese medicine disease diagnosis, accounted for 98.70%, 90.76%, respectively. The lower is rationality of prevention, accounted for 49.27%. The safety and economy of the guidelines are better, accounted for 97.02%, 95.11%, respectively. The comprehensive evaluation results showed that the overall treatment effect and technical level, satisfaction degree, applicability in clinical practice which were 7-9 points is 81.52%, 80.60%, 79.30%.The complex evaluation of diagnosis and treatment of common diseases of coloproctology in TCM guidelines is good, and suitable for clinical application with increase the content of rationality of prevention.

[Clinical application evaluation of Guidelines for Diagnosis and Treatment of Common Diseases of Gynecology in Traditional Chinese Medicine].

To evaluate the clinical applicability and application of Guidelines for Diagnosis and Treatment of Common Diseases of Gynecology in Traditional Chinese Medicine, 11 diseases from Guidelines for Diagnosis and Treatment of Common Diseases of Gynecology in Traditional Chinese Medicine were evaluated by methods of questionnaire and prospective case study at 16 construction units for traditional Chinese medicine standards research and extension. Results showed that 361 clinical doctors accepted the applicability survey of guidelines, and 87.26% of them were more familiar to the guideline and 25.21% of them used the guideline. In syndrome differentiation and treatment related contents, rationality of prescription medication and syndrome classification was higher, accounted for 91.69% and 86.98% respectively, but the rationality of recuperation prevention was lower, accounted for 44.6%. 75.62% clinical doctors believed that the Guidelines for Diagnosis and Treatment of Common Diseases of Gynecology in Traditional Chinese Medicine was applicable. The application of the guidelines is evaluated by prospective observation of 2 935 cases. The higher compliance between the guideline and clinical practice was present in TCM (traditional Chinese medicine) disease diagnosis and WM (western medicine) disease diagnosis, accounted for 98.30% and 94.11% respectively. The lower compliance was present in recuperation prevention, accounted for 59.39%. The safety and economy of the guideline was higher, accounting for 95.64%, 94.75%, respectively. The comprehensive evaluation results showed that the rate of the overall treatment effect with technical level, satisfaction degree or applicability in clinical practice which were 7-9 points is 77.38%, 74.00%, 76.90% respectively. This guideline has a high clinical compliance and can be used as a standard for common diseases of gynecology, but there are also some conditions with poor applicability, which does not conform to the actual situation, and needs to be further revised.

[Clinical application evaluation of Guidelines for Diagnosis and Treatment of Common Diseases of Dermatology in Traditional Chinese Medicine].

To assess the quality and application effect of Guidelines for Diagnosis and Treatment of Common Diseases of Dermatology in Traditional Chinese Medicine(Guidelines) through the applicability and applicability evaluation respectively. The questionnaire survey was adopted to evaluate the applicability of the Guidelines, including the utilization, quality, and clinical application conditions. The results showed that the familiarity rate and utilization rate of the Guidelines were 85.37%, 48.78%, respectively. The data showed that the familiarity and the utilization rates were different in the working staff with different professional titles. The evaluation level was the lowest given by the staff with junior professional title (70.97%, 29.03%) in comparison. The assessment showed the overall quality of the Guideline was good and slightly low level for the rationality scores of the other therapeutic methods as well as for the recuperation and prevention (80.49%, 85.37%), which was in line with the clinical compliance of the Guideline. The perspective observation of clinical cases was used for the applicability evaluation, including clinical compliance of the Guideline, effect evaluation, and comprehensive assessment, et al. The results showed that the safety score was the highest, followed by the economic issue and efficacy. For the comprehensive evaluation of the applicability, complete applicability accounted for 29.27%, and the general applicability accounted for 87.80%. It was showed in the three index scores of the applicability evaluation that the accumulative score 7-9 scores were 75.65%, 73.89%, 71.12%. Through the applicability and applicability evaluation, the Guideline was satisfactory in the overall quality, high in the safety of clinical application and good in efficacy and economic issues. There are some limits on the development method and technical issues in the Guideline, which is required to be supplemented in the revision. Additionally, the strategy study on the promotion of the Guideline should be enhanced so as to expedite the recognition and utilization of the Guideline.

[Clinical application evaluation of Guidelines for Diagnosis and Treatment of Cancer in Traditional Chinese Medicine].

This study aims to evaluate the adaptability and applicability of Guidelines for the Diagnosis and Treatment of Cancer in Traditional Chinese Medicine. The assessment methods included adaptability assessment and applicability assessment. The adaptability assessment was based on the questionnaire survey to evaluate the familiarity, utilization, quality, and clinical application of the Guidelines; applicability assessment was based on the prospective observation of 853 clinical cases to investigate the applicability and effect of the Guidelines, including effectiveness, economy and safety. Statistical analysis for basic description, construction of different comparison groups for cross or hierarchical statistical test, multi-factor analysis, and confounding factors were used in the study. Adaptability assessment results showed that 63.03% of TCM doctors considered guidelines as good or very good applicability and 4.24% of TCM doctors considered guidelines with very poor applicability in clinical practice. For the applicability evaluation, TCM doctors considered that the "overall efficacy and technology level", "satisfactory degree" and "adaptability in clinical practice" of the guideline were 85.46%, 80.43% and 69.40% respectively. The results showed that guideline was well known among TCM doctors, especially junior TCM doctors. Adaptability and applicability of Guidelines were totally good but the quality and adaptability of the intervention schemes were still week, so the quality of Guidelines should be improved by revision.

[The Study on the Characteristics of Organic Pollution in Typical Herbicide Plant Wastewater].

Herbicide wastewater is one of tne industrial wastewater, it has high salt content, poor biodegradability, biodegradable characteristics. Nitrogen-containing organic compounds are dominated in dissolved organic matter and dissolved organic matter of wastewater, BOD: COD = 0.045, C:N:P = 692:426:1. Applying static headspace, purg and trap, solid-phase extraction, solid-phase microextraction and liquid-liquid extraction as pretreatment methods combined with gas chromatography/mass spectrometry (GC/MS), which qualitatively analyzed the organic components of the Atrazine, acetochlor herbicide production wastewater and researched the UV spectrum, three-dimensional fluorescence spectroscopy of the wastewater and its major pollutants. The study of GC/MS indicated that Wastewater contained chlorinated hydrocarbons, BTEX and triazines, amides herbicides etc. 38 kinds of volatile and semi-volatile organic compounds, atrazine and acetochlor herbicides accounted for 87. 99%. Affected monocyclic or heterocyclic substances, the ultraviolet absorption spectrum of the wastewater in 210-230 and 250-270 nm in that the amino group lead to the UV absorption red shift 20 nm. Wastewater generated 5 fluorescence peak in λ(ex)/λ(em) = 200-280/300-400 nm, such as a(225/305 nm), b(265/365 nm), c(275/305 nm), d(285/390 nm), e(320/375 nm). Based on three-dimensional fluorescence results of the different functional groups of the characteristics organic, fluorescent area of unsaturated bond is in λ(ex)/λ(em) = 215-230/290-340 nm, the main contribution of the fluorescent substance in the region were olefins, benzene, heterocyclic in the wastewater; fluorescent area of Phenolic hydroxyl and carbonyl is in λ(ex)/λ(em) = 270/300 nm, the main contribution of the fluorescent substance in the region were phenols, ketones.

[Diterpenoids from Scutellaria strigillosa].

By means of preparative HPTLC and column chromatography over silica gel and Sephadex LH-20, nine diterpenoids were isolated and purified from the whole plants of Scutellaria strigillosa. Based on the physico-chemical properties and spectral data, their structures were elucidated as: 6-O-acetyl-7-O-nicotinoylscutebarbatine G(1), 6-O-nicotinoyl-7-O-acetylscutebarbatine G(2), 6,7-di-O-nicotinoylscutebarbatine G(3), scutebarbatine K(4), scutebarbatine B(5), 6-O-acetylscutehenanine A(6), 6-O-nicotinoylbarba- tin A(7), 6,7-di-O-acetoxylbarbatin A(8), scutebarbatine F(9). Compound 1 is a new diterpenoid, and compounds 2-9 were isolated from Scutellaria strigillosa for the first time.

Targeting of mTORC1/2 by the mTOR kinase inhibitor PP242 induces apoptosis in AML cells under conditions mimicking the bone marrow microenvironment.

The interactions between the bone marrow (BM) microenvironment and acute myeloid leukemia (AML) is known to promote survival of AML cells. In this study, we used reverse phase-protein array (RPPA) technology to measure changes in multiple proteins induced by stroma in leukemic cells. We then investigated the potential of an mTOR kinase inhibitor, PP242, to disrupt leukemia/stroma interactions, and examined the effects of PP242 in vivo using a mouse model. Using RPPA, we confirmed that multiple survival signaling pathways, including the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR), were up-regulated in primary AML cells cocultured with stroma. PP242 effectively induced apoptosis in primary samples cultured with or without stroma. Mechanistically, PP242 attenuated the activities of mTORC1 and mTORC2, sequentially inhibited phosphorylated AKT, S6K, and 4EBP1, and concurrently suppressed chemokine receptor CXCR4 expression in primary leukemic cells and in stromal cells cultured alone or cocultured with leukemic cells. In the in vivo leukemia mouse model, PP242 inhibited mTOR signaling in leukemic cells and demonstrated a greater antileukemia effect than rapamycin. Our findings indicate that disrupting mTOR/AKT signaling with a selective mTOR kinase inhibitor can effectively target leukemic cells within the BM microenvironment.

Human extramedullary bone marrow in mice: a novel in vivo model of genetically controlled hematopoietic microenvironment.

The interactions between hematopoietic cells and the bone marrow (BM) microenvironment play a critical role in normal and malignant hematopoiesis and drug resistance. These interactions within the BM niche are unique and could be important for developing new therapies. Here, we describe the development of extramedullary bone and bone marrow using human mesenchymal stromal cells and endothelial colony-forming cells implanted subcutaneously into immunodeficient mice. We demonstrate the engraftment of human normal and leukemic cells engraft into the human extramedullary bone marrow. When normal hematopoietic cells are engrafted into the model, only discrete areas of the BM are hypoxic, whereas leukemia engraftment results in widespread severe hypoxia, just as recently reported by us in human leukemias. Importantly, the hematopoietic cell engraftment could be altered by genetical manipulation of the bone marrow microenvironment: Extramedullary bone marrow in which hypoxia-inducible factor 1α was knocked down in mesenchymal stromal cells by lentiviral transfer of short hairpin RNA showed significant reduction (50% ± 6%; P = .0006) in human leukemic cell engraftment. These results highlight the potential of a novel in vivo model of human BM microenvironment that can be genetically modified. The model could be useful for the study of leukemia biology and for the development of novel therapeutic modalities aimed at modifying the hematopoietic microenvironment.

Mechanisms of apoptosis sensitivity and resistance to the BH3 mimetic ABT-737 in acute myeloid leukemia.

BCL-2 proteins are critical for cell survival and are overexpressed in many tumors. ABT-737 is a small-molecule BH3 mimetic that exhibits single-agent activity against lymphoma and small-cell lung cancer in preclinical studies. We here report that ABT-737 effectively kills acute myeloid leukemia blast, progenitor, and stem cells without affecting normal hematopoietic cells. ABT-737 induced the disruption of the BCL-2/BAX complex and BAK-dependent but BIM-independent activation of the intrinsic apoptotic pathway. In cells with phosphorylated BCL-2 or increased MCL-1, ABT-737 was inactive. Inhibition of BCL-2 phosphorylation and reduction of MCL-1 expression restored sensitivity to ABT-737. These data suggest that ABT-737 could be a highly effective antileukemia agent when the mechanisms of resistance identified here are considered.