Ex vivo expansion potential of murine hematopoietic stem cells is a rare property only partially predicted by phenotype.

The scarcity of hematopoietic stem cells (HSCs) restricts their use in both clinical settings and experimental research. Here, we examined a recently developed method for expanding rigorously purified murine HSCs ex vivo. After 3 weeks of culture, only 0.1% of cells exhibited the input HSC phenotype, but these accounted for almost all functional long-term HSC activity. Input HSCs displayed varying potential for ex vivo self-renewal, with alternative outcomes revealed by single-cell multimodal RNA and ATAC sequencing profiling. While most HSC progeny offered only transient in vivo reconstitution, these cells efficiently rescued mice from lethal myeloablation. The amplification of functional HSC activity allowed for long-term multilineage engraftment in unconditioned hosts that associated with a return of HSCs to quiescence. Thereby, our findings identify several key considerations for ex vivo HSC expansion, with major implications also for assessment of normal HSC activity.

A temporal developmental map separates human NK cells from noncytotoxic ILCs through clonal and single-cell analysis.

ABSTRACT: Natural killer (NK) cells represent the cytotoxic member within the innate lymphoid cell (ILC) family that are important against viral infections and cancer. Although the NK cell emergence from hematopoietic stem and progenitor cells through multiple intermediate stages and the underlying regulatory gene network has been extensively studied in mice, this process is not well characterized in humans. Here, using a temporal in vitro model to reconstruct the developmental trajectory of NK lineage, we identified an ILC-restricted oligopotent stage 3a CD34-CD117+CD161+CD45RA+CD56- progenitor population, that exclusively gave rise to CD56-expressing ILCs in vitro. We also further investigated a previously nonappreciated heterogeneity within the CD56+CD94-NKp44+ subset, phenotypically equivalent to stage 3b population containing both group-1 ILC and RORγt+ ILC3 cells, that could be further separated based on their differential expression of DNAM-1 and CD161 receptors. We confirmed that DNAM-1hi S3b and CD161hiCD117hi ILC3 populations distinctively differed in their expression of effector molecules, cytokine secretion, and cytotoxic activity. Furthermore, analysis of lineage output using DNA-barcode tracing across these stages supported a close developmental relationship between S3b-NK and S4-NK (CD56+CD94+) cells, whereas distant to the ILC3 subset. Cross-referencing gene signatures of culture-derived NK cells and other noncytotoxic ILCs with publicly available data sets validated that these in vitro stages highly resemble transcriptional profiles of respective in vivo ILC counterparts. Finally, by integrating RNA velocity and gene network analysis through single-cell regulatory network inference and clustering we unravel a network of coordinated and highly dynamic regulons driving the cytotoxic NK cell program, as a guide map for future studies on NK cell regulation.

Evaluation of moisture-related attenuation coefficient and water diffusion velocity in human skin using optical coherence tomography.

In this study, time-resolved optical coherence tomography (OCT) scanning images of the process of water diffusion in the skin that illustrate the enhancement in the backscattered intensities due to the increased water concentration are presented. In our experiments, the water concentration in the skin was increased by soaking the hand in water, and the same region of the skin was scanned and measured with the OCT system and a commercial moisture monitor every three minutes. To quantitatively analyze the moisture-related optical properties and the velocity of water diffusion in human skin, the attenuation coefficients of the skin, including the epidermis and dermis layers, were evaluated. Furthermore, the evaluated attenuation coefficients were compared with the measurements made using the commercial moisture monitor. The results demonstrate that the attenuation coefficient increases as the water concentration increases. Furthermore, by evaluating the positions of center-of mass of the backscattered intensities from OCT images, the diffusion velocity can be estimated. In contrast to the commercial moisture monitor, OCT can provide three-dimensional structural images of the skin and characterize its optical property, which together can be used to observe morphological changes and quantitatively evaluate the moisture-related attenuation coefficients in different skin layers.

A fetal tumor suppressor axis abrogates MLL-fusion-driven acute myeloid leukemia.

MLL-rearrangements (MLL-r) are recurrent genetic events in acute myeloid leukemia (AML) and frequently associate with poor prognosis. In infants, MLL-r can be sufficient to drive transformation. However, despite the prenatal origin of MLL-r in these patients, congenital leukemia is very rare with transformation usually occurring postnatally. The influence of prenatal signals on leukemogenesis, such as those mediated by the fetal-specific protein LIN28B, remains controversial. Here, using a dual-transgenic mouse model that co-expresses MLL-ENL and LIN28B, we investigate the impact of LIN28B on AML. LIN28B impedes the progression of MLL-r AML through compromised leukemia-initiating cell activity and suppression of MYB signaling. Mechanistically, LIN28B directly binds to MYBBP1A mRNA, resulting in elevated protein levels of this MYB co-repressor. Functionally, overexpression of MYBBP1A phenocopies the tumor-suppressor effects of LIN28B, while its perturbation omits it. Thereby, we propose that developmentally restricted expression of LIN28B provides a layer of protection against MYB-dependent AML.

Bmi1 induction protects hematopoietic stem cells against pronounced long-term hematopoietic stress.

The Polycomb complex protein Bmi1 is regarded as a master regulator of hematopoietic stem cells (HSCs). In the blood system, HSCs express Bmi1 most abundantly, and Bmi1 expression wanes as cells differentiate. Furthermore, Bmi1 has been found to be overexpressed in several hematologic cancers. Most studies exploring the normal role of Bmi1 in HSC biology have used loss-of-function models, which have established Bmi1 as an important regulator for HSC maintenance. Additionally, gain-of-function studies using retroviral and lentiviral approaches have observed increased self-renewal of Bmi1-transduced HSCs. However, the clinical and biological relevance of such studies is typically hampered by uncontrolled transgenic integration and supraphysiological expression levels. Here, we describe how we developed a novel tetracycline-inducible gain-of-function Bmi1 (iBmi1) transgenic mouse model. We found that Bmi1 induction had minor, if any, effects on steady-state hematopoiesis or after 5-fluorouracil-induced cytostatic stress. On the contrary, secondary transplantation of iBmi1 HSCs into wild-type recipients resulted in marked increases in the number and chimerism of HSCs. These data, in concert with previous loss-of-function studies, suggest that although endogenous Bmi1 levels are required and sufficient for normal HSC maintenance, the stabilization of these levels over time protects HSCs from transplantation-associated stress.

Bioinformatic analysis identifies HPV-related tumor microenvironment remodeling prognostic biomarkers in head and neck squamous cell carcinoma.

Head and neck squamous cell carcinomas (HNSCCs) are highly aggressive tumors with rapid progression and poor prognosis. Human papillomavirus (HPV) infection has been identified as one of the most important carcinogens for HNSCC. As an early event in HNSCC, infection with HPV leads to altered immune profiles in the tumor microenvironment (TME). The TME plays a key role in the progression and transformation of HNSCC. However, the TME in HNSCC is a complex and heterogeneous mix of tumor cells, fibroblasts, different types of infiltrating immune cells, and extracellular matrix. Biomarkers relevant to the TME, and the biological role of these biomarkers, remain poorly understood. To this end, we performed comprehensive analysis of the RNA sequencing (RNA-Seq) data from tumor tissue of 502 patients with HNSCC and healthy tissue of 44 control samples. In total, we identified 4,237 differentially expressed genes, including 2,062 upregulated and 2,175 downregulated genes. Further in-depth bioinformatic analysis suggested 19 HNSCC tumor tissue-specific genes. In the subsequent analysis, we focused on the biomarker candidates shown to be significantly associated with unfavorable patient survival: ITGA5, PLAU, PLAUR, SERPINE1, TGFB1, and VEGFC. We found that the expression of these genes was negatively regulated by DNA methylation. Strikingly, all of these potential biomarkers are profoundly involved in the activation of the epithelial-mesenchymal transition (EMT) pathway in HNSCCs. In addition, these targets were found to be positively correlated with the immune invasion levels of CD4+ T cells, macrophages, neutrophils, and dendritic cells, but negatively correlated with B-cell infiltration and CD8+ T-cell invasion. Notably, our data showed that the expression levels of ITGA5, PLAU, PLAUR, SERPINE1, and TGFB1 were significantly overexpressed in HPV-positive HNSCCs compared to normal controls, indicating the potential role of these biomarkers as transformation and/or malignant progression markers for HNSCCs in patients with HPV infection. Taken together, the results of our study propose ITGA5, PLAU, PLAUR, SERPINE1, and TGFB1 as potential prognostic biomarkers for HNSCCs, which might be involved in the HPV-related TME remodeling of HNSCC. Our findings provide important implications for the development and/or improvement of patient stratification and customized immunotherapies in HNSCC.

A somatic mutation in moesin drives progression into acute myeloid leukemia.

Acute myeloid leukemia (AML) arises when leukemia-initiating cells, defined by a primary genetic lesion, acquire subsequent molecular changes whose cumulative effects bypass tumor suppression. The changes that underlie AML pathogenesis not only provide insights into the biology of transformation but also reveal novel therapeutic opportunities. However, backtracking these events in transformed human AML samples is challenging, if at all possible. Here, we approached this question using a murine in vivo model with an MLL-ENL fusion protein as a primary molecular event. Upon clonal transformation, we identified and extensively verified a recurrent codon-changing mutation (Arg295Cys) in the ERM protein moesin that markedly accelerated leukemogenesis. Human cancer-associated moesin mutations at the conserved arginine-295 residue similarly enhanced MLL-ENL-driven leukemogenesis. Mechanistically, the mutation interrupted the stability of moesin and conferred a neomorphic activity to the protein, which converged on enhanced extracellular signal-regulated kinase activity. Thereby, our studies demonstrate a critical role of ERM proteins in AML, with implications also for human cancer.

Ultrasonographic Characteristics of Cortical Sulcus Development in the Human Fetus between 18 and 41 Weeks of Gestation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Fetal brain development is a complicated process that continues throughout pregnancy. Fetal sulcus development has typical morphological features. Assessment of fetal sulcus development to understand the cortical maturation and development by prenatal ultrasound has become widespread. This study aimed to explore a reliable method to assess cortical sulcus and to describe the normal sonographic features of cortical sulcus development in the human fetus between 18 and 41 weeks of gestation.</p><p><b>METHODS</b>A cross-sectional study was designed to examine the fetal cortical sulcus development at 18-41 weeks of gestation. Ultrasound was used to examine the insula, sylvian fissure (SF), parieto-occipital fissure (POF), and calcarine fissure (CF). Bland-Altman plots were used for assessing the concordance, and the intraclass correlation coefficient was used for assessing the reliability.</p><p><b>RESULTS</b>SF images were successfully obtained in 100% of participants at 22 weeks of gestation, while the POF images and CF images could be obtained in 100% at 23 weeks of gestation and 24 weeks of gestation, respectively. The SF width, temporal lobe depth, POF depth, and the CF depth increased with the developed gestation. The width of uncovered insula and the POF angle decreased with the developed gestation. By 23 weeks of gestation, the insula was beginning to be covered. Moreover, it completed at 35 weeks of gestation. The intra- and inter-observer agreements showed consistent reproducibility.</p><p><b>CONCLUSIONS</b>This study defined standard views of the fetal sulcus as well as the normal reference ranges of these sulcus measurements between 18 and 41 weeks of gestation. Such ultrasonographic measurements could be used to identify fetuses at risk of fetal neurological structural disorders.</p>

Combination therapy of FK228 with rapamycin synergistically promotes human breast cancer cell apoptosis by DNA damage and cell cycle arrest / 中国病理生理杂志

[ ABSTRACT] AIM:To investigate the depressant effect of FK228 combined with rapamycin on the human breast cancer cell line MCF-7 and MDA-MB-435.METHODS:FK228, a new histone deacetylase inhibitor, and rapamycin, the specific inhibitor of the mammalian target of rapamycin ( mTOR) protein, were used in the study.MCF-7 cells and MDA-MB-435 cells were exposed to different concentrations of FK228 and rapamycin.The inhibitory rate of cell growth was de-termined by SRB assay.Combination index ( CI) was used to evaluate the interaction between FK228 and rapamycin.The expression of the apoptotic proteins, cycle proteins and nucleic acid proteins were detected by Western blotting.The cell cycle was analyzed by flow cytometry.RESULTS: Both FK228 and rapamycin showed growth inhibitory effects on the breast cancer cell lines in a time-and dose-dependent manner.CI of the 2 drugs was less than 1 when the inhibitory rate of the cell growth was 50%effective dose (ED50)~ED70, indicating a synergistic effect.The combination therapy of FK228 with rapamycin increased the apoptotic proteins, and induced the down-regulation of phosphorylated Akt and over-expres-sion of caspase-3 compared with a single use of the drugs.The combination therapy of FK228 with rapamycin reduced the cycle proteins, and the cell cycle was arrested in G2/M.The levels of phosphorylated H2AX and acetylated H3 were ob-viously increased after combination therapy.CONCLUSION:The combination therapy of FK228 with rapamycin inhibits the cell proliferation and increases apoptosis with a synergistic effect, which may become a new trend for treating endometri-al cancer.

Treatment of two chronic myeloid leukemia patients with V299L mutation by using nilotinib / 中国实验血液学杂志

This study was aimed to enhance clinical understanding the effect of nilotinib on CML patients with V299L mutation who were resistant to imatinib. Bone marrow specimens from 2 cases of CML with V299L mutation were collected before and after the treatment with nilotinib. ABL mutation was detected by nested reverse transcription polymerase chain reaction (PCR) followed by direct sequencing. The clinical characteristics of the two cases were analyzed. The results showed that both cases were resistant to imatinib presented V299L mutation. Out of them 1 case achieved complete haematological response (CHR) after treatment with nilotinib for 6 months and another case abstained obvious molecular response after using nilotinib for 7 month. V299L mutation of both cases was turned into negative after the treatment with nilotinib. It is concluded that the nilotinib can safely and effectively override tyrosine kinase inhibitor (TKI) resistance mediated by the V299L mutation. The safety and efficacy of nilotinib for treatment of CML patients with TKI resistance and V299L mutation are satisfactory.

Prenatal diagnosis of dural sinus malformation by ultrasound / 中华医学超声杂志（电子版）

Objective To assess the prenatal features of dural sinus malformation (DSM) by ultrasound. Methods The prenatal ultrasonography and MRI examination were applied in three fetuses who were suspected as brain abnormalities and transferred to Shenzhen Maternity and Child Healthcare Hospital for detailed antenatal ultrasound examination. Comparative analysis was performed on MRI, autopsy and prenatal ultrasonography. The prenatal characteristics were summarized. Results In the sonograms of all three cases, the torcular Herophili and superior sagittal sinus were dilated. No blood lfow was detected within or around lesions by color Doppler imaging. Posterior intracranial dual sinus thrombosis was detected in one case. MRI examinations were applied in two fetuses. The results of prenatal ultrasonography were consisted with those of MRI, MRI imaging showed dilated torcular Herophili and superior sagittal sinus with short T1 and short T2 signal. The thrombosis was presented as iso-hypointense with focal eccentric hyperintense. One case was undertook autopsy and the result was consisted with the prenatal sonographic findings. Conclusions The typical sonographic features of DSM is dilated torcular Herophili and superior sagittal sinus with no blood lfow in color Doppler imaging. DSM should be excluded when anechoic area was detected at the rear part of midline.

Effect of magnesium isoglycyrrhizinate on PLA2 during liver tissue injury following limb ischemia/reperfusion in rats / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the effects of magnesium isoglycyrrhizinate (MI) on the changes of phospholipase A2 (PLA2) induced during liver tissue injury following limb ischemia/reperfusion (I/R) in rats.</p><p><b>METHOD</b>Twenty-four healthy male Sprague-Dawley rats weighing (230+/-30) g were randomly divided into three groups (n = 8 each) as follows: control (Group C: anesthetization without any ischemia); I/R injury (Group I/R: 4 h ischemia induced by rubber band ligation of the left hind limb around the roots of the hind limb, followed by 6 h of reperfusion, with 1 mL normal saline given via tail vein prior to reperfusion); MI-treated group (Group MI: underwent ischemia and reperfusion, with 1 mL MI (30 mg/kg) infused prior to reperfusion). Levels of TNFa and PLA2 in plasma and liver tissue were measured by enzyme-linked immunosorbent assay (ELISA). Levels of plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase (CK), myeloperoxidase (MPO), and malondialdehyde (MDA), and activities of MPO and MDA in liver tissue were measured by colorimetry. Ultrastructural changes of liver tissue were observed by electron microscopy.</p><p><b>RESULTS</b>The MI group had significantly lower PLA2 and TNFa in liver homogenates and serum than the I/R group (both P less than 0.05). Serum ALT, AST, LDH, and CK were significantly lower in the MI group than in the I/R group (all P less than 0.05), as were the levels of MPO and MDA in liver homogenates and serum (all P less than 0.05). The I/R group showed significantly more liver tissue damage, which appeared to be attenuated in the MI group.</p><p><b>CONCLUSION</b>MI treatment can inhibit the I/R-induced TNFa, PLA2, and MDA in plasma and liver tissue, as well as decrease the I/R-induced MPO activity in rats. Thus, MI may have protective effects against liver tissue injury following limb ischemia/reperfusion.</p>

Clinical and genetic analysis of a pedigree of Kennedy disease / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To review the clinical and genetic features of a pedigree of Kennedy disease in China.</p><p><b>METHODS</b>The clinical data of patients from a Kennedy disease family were collected. The numbers of trinucleotide CAG repeats in exon 1 of the androgen receptor gene were determined by DNA sequencing and repeat fragment analysis.</p><p><b>RESULTS</b>In the pedigree, 4 patients were identified as Kennedy disease. Clinical manifested with adult-onset, progressive proximal limb muscle weakness and atrophy, gynecomastia, oligospermia were also presented. The number of trinucleotide CAG repeats in exon 1 of the androgen receptor gene was 51 in the proband. The electrophysiological study showed sensory and motor involvement and their serum triglycerides values were elevated significantly.</p><p><b>CONCLUSION</b>Androgen receptors gene testing is the most reliable diagnosing method, the patients suspected as Kennedy disease should have a gene testing of androgen receptors.</p>

Analysis of 993 cases of fetal malformations from 1999 to 2006 / 中国医学科学院学报

<p><b>OBJECTIVE</b>To study the value of prenatal ultrasound in the diagnosis of fetal malformations.</p><p><b>METHODS</b>We retrospectively analyzed the clinical data of 993 cases of neonates and induced babies with malformations who were labored in our hospital from January 1999 to October 2006.</p><p><b>RESULTS</b>The incidence rate of fetal malformation was 22.5 per thousand in our study group. The detection rate of prenatal ultrasound was 79.02% (1 062/1 344), among which the detection rate of the severe malformations (87.58%, 860/982) were significantly higher than that of the minor malformations (55.80%, 202/362) (P < 0.005). The false negative rate was high for the extremity malformations (39.46%) and facial malformations (31.91%), especially the acrosclerodermas, simple cleft palates, and ear deformities.</p><p><b>CONCLUSION</b>Prenatal ultrasound is sensitive for fetal severe malformations, while the detection rate is low for fetal minor malformations.</p>

Ultrasonographic evaluation of fetal facial anatomy (I): ultrasonographic features of normal fetal face in vitro study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Because of lacking skills in scanning the normal fetal facial structures and their corresponding ultrasonic features, misdiagnoses frequently occur. Therefore, we studied the appearance features and improved displaying skills of fetal facial anatomy in order to provide basis for prenatal diagnosis.</p><p><b>METHODS</b>Twenty fetuses with normal facial anatomy from induced labor because of other malformations except facial anomalies were immersed in a water bath and then scanned ultrasonographically on coronal, sagittal and transverse planes to define the ultrasonic image features of normal anatomy. The coronal and sagittal planes obtained from the submandibular triangle were used for displaying the soft and hard palate in particular.</p><p><b>RESULTS</b>Facial anatomic structures of the fetus can be clearly displayed through the three routine orthogonal planes. However, the soft and hard palate can be displayed on the planes obtained from the submandibular triangle only.</p><p><b>CONCLUSIONS</b>The superficial soft tissues and deep bony structures of the fetal face can be recognized and evaluated by routine ultrasonographic images, which is a reliable prenatal diagnostic technique to evaluate the fetal facial anatomy. The soft and hard palate can be well demonstrated by the submandibular triangle approach.</p>