Thermodynamic Controlled Regioselective C1-Functionalization of Indolizines with 3-Hydroxyisoindolinones via Brønsted Acid Catalyzed aza-Friedel-Crafts Reaction

A Brønsted acid catalyzed aza-Friedel-Crafts reaction of indolizines with 3-hydroxyisoindolinones has been established, which constructs isoindolinone derivatives bearing a tetrasubstituted stereocenter in good to high yields and enantioselectivities. Notably, this strategy provides a new access to C1-functionalization of indolizines with excellent regioselectivities. Moreover, this intriguing C1-regioselective transformation was induced under thermodynamic control.

Organocatalytic regio- and enantioselective C1-arylation of β,γ-alkynyl-α-imino esters with pyrrolo[2,1-a]isoquinolines

We herein report regio- and enantioselective arylation of β,γ-alkynyl-α-imino esters with pyrroloisoquinolines. Using chiral phosphoric acid catalysts, a wide range of novel axially chiral tetrasubstituted α-amino allenoates were accessed in good yields with excellent enantioselectivities. Notably, this transformation occurred preferentially at the sterically more hindered C1-position of pyrroloisoquinolines. The potential scalability and late-stage functionalization demonstrated the utility of the current protocol.

Bifunctional Squaramide-Catalyzed Asymmetric Cascade Reaction of Benzothiazoles with 2-Nitroallylic Acetates or Nitroenynes

We describe here an organocatalytic asymmetric cascade formal [3 + 3] cycloaddition of benzothiazoles with 2-nitroallylic acetates and nitroenynes. This dearomative methodology provided a facile and efficient strategy for the construction of a broad range of valuable benzothiazolopyridines bearing two adjacent stereogenic centers in moderate to good yields with good to excellent stereocontrol.

Prediction of Radiomics-Based Machine Learning for Specific Dosimetric Verification of Pelvic Intensity Modulated Radiotherapy

PURPOSE/OBJECTIVE(S)

To establish the different machine learning classification predict models of gamma pass rates for specific dosimetric verification of pelvic intensity modulated radiotherapy plan which based on the radiomic features and to explore the best prediction model.

MATERIALS/METHODS

Retrospective analysis of the 3D dosimetric verification results based on measurements with gamma pass rate criteria of 3%/2 mm and 10% dose threshold of 196 pelvic intensity-modulated radiotherapy plans was carried. Prediction models were established by extracting radiomic features data. Four machine learning algorithms, random forest, support vector machine, adaptive boosting and gradient boosting decision trees, were used to calculate the AUC value, sensitivity and specificity respectively. The classification performance of the four prediction models were evaluated.

RESULTS

The sensitivity and specificity of the random forest, support vector machine, adaptive boosting, and gradient boosting decision trees models were 0.93,0.85,0.93,0.96, and 0.38,0.69,0.46, and 0.46, respectively. The AUC values for the random forest model and the adaptive boosting model were 0.81 and 0.82, respectively, and the AUC values for the support vector machine and gradient boosting decision tree models were 0.87.

CONCLUSION

Machine learning methods based on radiomics can be used to establish a prediction model of gamma pass rate for specific dosimetric verification of pelvic intensity modulated radiotherapy. The classification performance of support vector machine model and gradient boosting decision trees model is better than that of random forest model and adaptive boosting model. The prediction model for a specific site is helpful to improve the performance of the model.

B-Cell-Derived TGF-β1 Inhibits Osteogenesis and Contributes to Bone Loss in Periodontitis

B cells play a vital role in the elimination of periodontal pathogens, the regulation of the immune response, and the induction of tissue destruction. However, the role of B cells in the dysfunction of mesenchymal stem cell (MSC) differentiation to osteoblasts in periodontitis (PD) has been poorly studied. Here we show that the frequency of CD45^-CD105⁺CD73⁺ MSCs in inflamed periodontal tissues is significantly decreased in patients with PD compared with that of healthy controls. CD19⁺ B cells dominate the infiltrated immune cells in periodontal tissues of patients with PD. Besides, B-cell depletion therapy reduces the alveolar bone loss in a ligature-induced murine PD model. B cells from PD mice express a high level of TGF-β1 and inhibit osteoblast differentiation by upregulating p-Smad2/3 expression and downregulating Runx2 expression. The inhibitory effect of PD B cells on osteoblast differentiation is reduced by TGF-β1 neutralization or Smad2/3 inhibitor. Importantly, B-cell-specific knockout of TGF-β1 in PD mice significantly increases the number of CD45^-CD105⁺Sca1⁺ MSCs, ALP-positive osteoblast activity, and alveolar bone volume but decreases TRAP-positive osteoclast activity compared with that from control littermates. Lastly, CD19⁺CD27⁺CD38^- memory B cells dominate the B-cell infiltrates in periodontal tissues from both patients with PD and patients with PD after initial periodontal therapy. Memory B cells in periodontal tissues of patients with PD express a high level of TGF-β1 and inhibit MSC differentiation to osteoblasts. Thus, TGF-β1 produced by B cells may contribute to alveolar bone loss in periodontitis, in part, by suppressing osteoblast activity.

Diastereoselective and E/Z-Selective Synthesis of Functionalized Quinolizine Scaffolds via the Dearomative Annulation of 2-Pyridylacetates with Nitroenynes

An organocatalytic Michael/aza-Michael cascade reaction was developed to build the functionalized quinolizine scaffolds in 60-82% yields, excellent diastereoselectivities, and E/Z selectivities. This protocol involves the [3 + 3] annulations of 2-pyridylacetates with nitroenynes through the dearomative strategy in the presence of an organic base under mild conditions. The versatile late-stage derivatizations further demonstrated the synthetic utility of this methodology.

Chiral Phosphoric Acid-Catalyzed Asymmetric Arylation of Indolizines: Atroposelective Access to Axially Chiral 3-Arylindolizines

We report herein a highly straightforward strategy for the synthesis of a new axially chiral 3-arylindolizine scaffold via organocatalytic asymmetric arylation reactions of indolizines and p-quinone esters. Using the chiral phosphoric acid catalyst, a series of axially chiral 3-arylindolizines were accessed in good to excellent yields and atropo-enantioselectivities. This approach features a broad substrate scope, mild reaction conditions, good scalability, and facile derivatization. Moreover, preliminary investigations based on nonlinear effects and a thermal racemization study demonstrated the intrinsic pathway for the formation of axial chirality and its potential utility.

Chiral Phosphoric Acid Catalyzed Desymmetrization of Cyclopentendiones via Friedel-Crafts Conjugate Addition of Indolizines

An organocatalytic highly diastero- and enantioselective Friedel-Crafts conjugate addition of indolizines to prochiral cyclopentenediones has been successfully developed. This desymmetric transformation provides a direct access to the desired indolizine-substituted cyclopentanediones in yields of 62-91% and excellent stereoselectivities. The utility of the approach was demonstrated by diverse late-stage functionalizations through reduction or oxidation. Importantly, the direct sp² C-H functionalization with nitromethane in one-pot process resulted in the indolizine-linked axially chiral styrene bearing a remote chiral center.

Sentinel lymph node biopsy with carbon nanoparticle suspension after neoadjuvant chemotherapy for breast cancer patients

INTRODUCTION

The aim of the study was to explore the feasibility of performing sentinel lymph node biopsy (SLNB) using a carbon nanoparticle suspension (CNPS) after neoadjuvant chemotherapy in breast cancer patients.

METHODS

Some 152 patients diagnosed with primary breast cancer (cT1-3N0-2M0) were recruited. Patients were divided into two groups according to axillary lymph node (ALN) status after four to six cycles of neoadjuvant chemotherapy. All patients received a CNPS injection, after which SLNB and axillary lymph node dissection (ALND) were performed.

RESULTS

Sentinel lymph nodes (SLN) of 143 patients were identified; with an accuracy rate of 94.4% and a false-negative rate of 9.9%. Group A included 67 patients, and the detection, accuracy and false-negative rates within this group were 95.5%, 96.9% and 6.7%, respectively. The corresponding rates for group B (85 patients) were 92.9%, 92.4% and 11.8%, respectively.

CONCLUSIONS

CNPS is an ideal tracer for improving the detection rate of SLN and can be used to determine SLN status following neoadjuvant chemotherapy.

Factors associated with Scrub Typhus infection: A case-control study from Luhe, China

INTRODUCTION

Scrub typhus (ST) is an acute febrile infection and remains a significant health problem globally. This study aimed to determine the factors associated with ST infection in Luhe District, China.

MATERIAL AND METHODS

The case-control study was conducted among 116 cases identified through passive surveillance systems over three years.The control subjects were 232 living in the same village for more than six months without any history of ST infection were selected by matching to the age (within 5-years) and identified through active surveillance. Statistical analyses were performed using SPSS v. 25.0 for Windows (IBM SPSS, Chicago, IL, USA).

RESULTS

The mean age of confirmed persons was 58.1(SD=10.15) years, while control subjects were 56.14 (11.57).There is no significant difference in gender, age, education, and occupations between case and control. Farmers had the most significant number of cases among occupational groups. The three factors that were significantly associated with an increased odds of having ST infection are bundling or moving waste straw (OR: 1.94, 95%CI; 0.99,381), morning exercise in the park or field (OR: 4.74 95%CI; 1.19, 18.95), and working as labourer in the vegetable field (OR:1.02, 95%CI:1.02,3.19).

CONCLUSIONS

Our findings suggested establishing a prevention and control strategy for these groups to lower ST development risk.

Perceptions of animal welfare and exotic pet ownership in China

China plays a critical role in global biodiversity conservation, as both a biodiversity hotspot and for its role in international and domestic animal trade. Efforts to promote wildlife conservation have sparked interest in the attitudes held by Chinese citizens towards animals. Using a questionnaire, we sought to investigate the attitudes of 317 Chinese nationals across 22 provincial-level administrative units regarding their uses of animals, their perceived emotional capacities and views on exotic pets. We reduced the variables related to perceived uses of animals via Principal Component Analysis and ran Generalised Linear Models and Structural Equation Modelling to test relationships between questionnaire-derived variables. Perceptions of animals were divided into two Kellert categories — Utilitarian and Humanistic uses — and 97% of participants believed in animals capacities to have and express emotions. We found few interactions, with exotic pets, ie playing with or taking photographs, but the acceptability of owning an exotic pet influenced the likelihood of purchasing one. A belief that animals express emotions encouraged people to look for them as pets but thinking that pets make people happy made exotic pet ownership less acceptable. The shift in attitudes to include humanistic perceptions of animals, a belief in animals as emotive beings and understanding of terminology changed from the previous utilitarian views of pre-reform China, suggesting a readiness to embrace further conservation efforts in China. This deeper understanding of Chinese attitudes toward animals and drivers of the exotic pet trade within China may enable conservation efforts to better target future campaigns.

The distinctive characteristics of the micro-vasculature and immune cell infiltration in cystic pancreatic neuroendocrine tumors

PURPOSE

Hypervascularity is a main characteristic of pancreatic neuroendocrine tumors (PanNETs), and cystic PanNETs (CPanNETs) are unique type of PanNETs in which the microenvironment remains unknown. We aim to compare the micro-vasculature features and immune cell infiltration between CPanNETs and solid PanNETs (SPanNETs).

METHODS

Data of 301 SPanNET and 36 CPanNET patients from a high-volume institution were evaluated. CD4, CD8, CD11c, CD15, CD20, CD68, CD34 and α-SMA expression levels were assessed by immunohistochemistry and immunofluorescent double staining. The microvessel density (MVD) and microvessel integrity (MVI) were examined.

RESULTS

MVD and MVI expression levels in CPanNETs were significantly higher than those in SPanNETs (p = 0.025 and 0.0092, respectively). CPanNETs had higher proportions of T1 (p = 0.023) and G1 (p = 0.052) than SPanNETs. In SPanNETs, higher MVD occurred in stages T1, N0 and G1 than in the T2/T3, N1 and G2 subgroups. In CPanNETs, CD34-MVD was uncorrelated with the T stage or grade. Higher CD34-MVD, but not MVI, was associated with better DFS (HR 0.3209, 95% CI 0.1259-0.8176, p = 0.004). There were significantly more peritumoral infiltrating immune cells than their intratumoral counterparts (p < 0.001 for each) in CPanNETs and SPanNETs. The mean number of peritumoral CD68 + TAM in CPanNETs was significantly lower than that in SPanNETs (p = 0.008). The counts of other peritumoral immune cells did not significantly differ between CPanNETs and SPanNETs.

CONCLUSIONS

CPanNETs had a microenvironment distinct from that of SPanNETs, including higher CD34-MVD, higher MVI and lower TAM. This specific microenvironment structure may partially help predicting the prognosis of patients with PanNET.

Organocatalytic Asymmetric Synthesis of Aza-Spirooxindoles via Michael/Friedel-Crafts Cascade Reaction of 1,3-Nitroenynes and 3-Pyrrolyloxindoles

An asymmetric [3+3] cyclization of nitroenynes and 3-pyrrolyloxindoles has been realized with a chiral bifunctional squaramide catalyst. This Michael/Friedel-Crafts cascade strategy provides a facile and efficient access to enantioenriched polycyclic aza-spirooxindoles with 32-95% isolated yields and excellent stereocontrol under mild reaction conditions.

Age-related histological changes in rat tibial

BACKGROUND

At present, studies on osteochondral morphogenesis only focus on a certain period of time or only provide a pattern diagram, but lack of dynamic tracking observation from the initiation of development to maturity. This study was to dynamically observe the changes of skeleton morphology and structure from embryo to adult, to provide research data for enriching the knowledge of bone and cartilage tissue structure.

MATERIALS AND METHODS

In the intrauterine experiment, 5 normal pregnant Wistar rats were sacrificed under anesthesia at gestational day (GD) 14, 17, 20, respectively. One of their offspring was randomly selected, and a total of 5 offspring were obtained at each time point. In the postnatal experiment, on the 7th and 10th day after birth and at postnatal weeks (PW) 2, 3, 6, 12, 28, 5 offspring rats from 5 different pregnant Wistar rats were randomly selected and sacrificed under anesthesia at each time point. After obtaining the above offspring, the soft tissue was removed, and the tibia of hind limbs was retained for paraffin-embedded section. After stained with Safranin-O-fast-green and hematoxylin, the morphological development of the tibia was observed under an optical microscope.

RESULTS

At GD14, there was no obvious joint space, the whole hind limb was cartilage and bone tissue was not visible. At GD17, visible joint space was seen and the chondrocytes in the center region appeared to hypertrophy. At GD20, the primary ossification center was obvious, and a typical epiphysis growth plate structure could be seen. On the 7th day after birth, the chondrocytes in the center of epiphysis cartilage were hypertrophic and differentiated, the cartilage canal grow from the cartilage surface toward the center of the epiphysis cartilage, at postnatal day 14, the secondary ossification center was formed. At this time, the tibia had typical morphological characteristics of the metaphysis, however, there was no obvious layered structure of articular cartilage; the stratified structure of articular cartilage could be seen at PW6, but its mature marker (tidemark) was still not visible; however, at PW12, typical four layers of articular cartilage appeared, and the tidemark was visible. The growth plates were clearly visible at PW2, 6 and 12. At PW28, growth plates could still be observed, but its morphology is abnormal.

CONCLUSIONS

Our results, for the first time, dynamically observed the morphological changes of osteochondral at critical period of development from embryo to adult, especially the process of cartilage canal participating in the formation of secondary ossification center.

Access to substituted cyclobutenes by tandem [3,3]-sigmatropic rearrangement/[2 + 2] cycloaddition of dipropargylphosphonates under Ag/Co relay catalysis

We present herein an unconventional tandem [3,3]-sigmatropic rearrangement/[2 + 2] cycloaddition of simple dipropargylphosphonates to deliver a range of bicyclic polysubstituted cyclobutenes and cyclobutanes under Ag/Co relay catalysis. An interesting switch from allene–allene to allene–alkyne cycloaddition was observed based on the substitution of the substrates, which further diversified the range of compounds accessible from this practical method. Significantly, preliminary biological screening of these new compounds identified promising candidates as suppressors of cellular proliferation.

In situ generation of allenes through [3,3]-sigmatropic rearrangement of propargylphosphonates. Divergent allene–allene or allene–alkyne cycloaddition by Ag/Co relay catalysis. Products as promising suppressors of cellular proliferation.

Highly diastereoselective synthesis of 3-methylenetetrahydropyrans by palladium-catalyzed oxa-[4 + 2] cycloaddition of 2-alkenylbenzothiazoles

A highly diastereoselective synthesis of 3-methylenetetrahydropyrans via palladium-catalyzed oxa-[4 + 2] cycloaddition of 2-alkenylbenzothiazoles with allyl carbonates bearing a nucleophilic alcohol side chain is presented. This synthetic methodology tolerates a wide variety of 2-alkenylbenzothiazoles and afforded the desired 3-methylenetetrahydropyrans in good yields and excellent dr. In addition, further derivatizations resulted in new scaffolds, making them useful synthetic precursors.

Organocatalytic asymmetric [4+2] cyclization of 2-benzothiazolimines with azlactones: access to chiral benzothiazolopyrimidine derivatives

A squaramide catalyzed regiospecific and stereoselective [4+2] cyclization of 2-benzothiazolimines with azlactones has been established.

High Expression of Human Leukocyte Antigen-G is Associated with a Poor Prognosis in Patients with PDAC

Pancreatic Adenocarcinoma (PDAC) is one of the most deadly malignant tumors worldwide. A variety of mechanisms are involved in PDAC biological behaviors, of which, the mechanisms of immune escape may be a pivotal hallmark. HLA-G is a tolerant molecule implicated in tumor escape and serves as a prognostic biomarker in tumors. Our study evaluated the expression of HLA-G in PDAC and explored its clinical significance. In a cohort of 122 PDAC patients, 78 patents (63.9%) exhibited high level of HLA-G tumor tissues. Multivariate analysis suggested that HLA-G level was an independent predictor for OS (HR = 3.894, 95% CI = 2.380-6.370, p <0.001). High level of HLA-G significantly correlated with PDAC aggressive features, such as more advanced stage (TNM Stage II) (p<0.001), extrapancreatic infiltration (T3 stage) (p<0.001), lymph node involvement (p=0.019) and poor differentiation (p=0.010). In western blot analysis, almost all of the tumor cell lines (5/6) expressed high levels of HLA-G. In ELISA analysis, the level of plasma sHLA-G in PDAC patients were significantly increased than in healthy control (P=0.0037). Further analysis revealed the level of sHLA-G inversely related to numbers of peripheral activated T cells (CD8+CD28+ T cells), which may indicate that sHLA-G inactivates T cell responses resulting in tumor immune escape. In conclusion, tumor-derived HLA-G may indicate the mechanism of immune escape and impaired PDAC clinical outcome, especially in early-stage patients, which may also be a potential therapeutic target.

Asymmetric synthesis of cyclopentanes bearing four contiguous stereocenters via an NHC-catalyzed Michael/Michael/esterification domino reaction

An NHC-catalyzed Michael/Michael/esterification domino reaction via homoenolate/enolate intermediates for the asymmetric synthesis of tetrasubstituted cyclopentanes bearing four contiguous stereocenters is described. A variety of α,β-unsaturated aldehydes and 2-nitroallylic acetates react well with good domino yields and high stereoselectivities.

Curved focal plane extreme ultraviolet detector array for a EUV camera on CHANG E lander

A novel curved focal plane extreme ultraviolet (EUV) detector array designed for a moon-based EUV camera is demonstrated. The curved focal plane detector array operating in a pulse-counting mode consists of a curved microchannel plate (MCP) stack and an induced charge wedge-strip anode (WSA). The curved MCP is fabricated by firstly thermally slumping of the MCPs, and then followed by optical polishing and core glass etching. By using this technology, curved MCPs with a length-to-diameter (L/D) ratio of 80:1 and a radius of curvature of 150 mm have been successfully achieved. The performance of the curved MCP detector is fully characterized in terms of the background noise, pulse height distribution, gain, image linearity and spatial resolution. It is measured that a spatial resolution of 7.13 lp/mm can be achieved with a background noise of less than 0.3 counts/cm2⋅s. The characterization results indicate that the curved focal plane detector can fulfill the requirements of the moon-based EUV camera.

Regio- and stereoselective synthesis of benzothiazolo-pyrimidinones via an NHC-catalyzed Mannich/lactamization domino reaction

An NHC-catalyzed regio- and stereoselective Mannich/lactamization domino reaction of N-(benzothiazolyl)imines with α-chloroaldehydes has been developed.

An NHC-catalyzed regio- and stereoselective Mannich/lactamization domino reaction of N-(benzothiazolyl)imines with α-chloroaldehydes has been developed. This new protocol provides a facile approach for the asymmetric synthesis of benzothiazolo-pyrimidinones and a pyrrolo[1,2-a]indolone in moderate to good yields (34–78%) and excellent stereoselectivities (87–99% ee, up to >20 : 1 d.r.).

N-Heterocyclic Carbene Catalyzed Enantioselective Annulation of Benzothiazolyl Ethyl Acetates with 2-Bromoenals

An N-heterocyclic carbene catalyzed enantioselective [3+3] annulation of benzothiazolyl acetates with 2-bromoenals has been developed. The protocol provides a direct asymmetric synthesis of dihydro-1H-benzothiazolopyridinones in good to very good yields and medium ee values. In many cases, the virtually enantiopure heterocycles are available through a single recrystallization (99% ee).

NHC-Catalyzed Asymmetric Synthesis of Functionalized Succinimides from Enals and α-Ketoamides

The efficient asymmetric synthesis of highly substituted succinimides from α,β-unsaturated aldehydes and α-ketoamides via NHC-catalyzed [3+2] cycloaddition has been developed. The new scalable protocol significantly expands the utility of NHC catalysis for the synthesis of heterocycles and provides easy access to assemble a wide range of succinimides from simple starting materials.

NHC-catalyzed activation of α,β-unsaturated N-acyltriazoles: an easy access to dihydropyranones

Employing the NHC-catalyzed activation of α,β-unsaturated N-acyltriazoles an efficient enantioselective synthesis of dihydropyranones via a formal [3+3] cycloaddition with 1,3-dicarbonyl compounds is described.

Asymmetric N-Heterocyclic Carbene Catalyzed Annulation of 2-Alkenylbenzothiazoles with α-Chloro Aldehydes

Diastereo- and enantioselective N-heterocyclic carbene catalyzed 1-azadiene Diels-Alder reactions of (E)-2-styrylbenzothiazoles with α-chloro aldehydes are reported. This annulation strategy provides an efficient access to medicinally important dihydrobenzothiazolopyridin-1-ones in good to excellent yields (44-97%) with very good to excellent stereoselectivities (up to 9:1 dr, 98% ee) and tolerates quite a range of substituents.

Severe and moderate haemophilia A and B in US females

Haemophilia A and B are rare X-lined hemorrhagic disorders that typically affect men. Women are usually asymptomatic carriers, but may be symptomatic and, rarely, also express severe (factor VIII (FVIII) or factor IX (FIX) <0.01 U mL(-1)) or moderately severe (FVIII/FIX 0.01-0.05 U mL(-1)) phenotypes. However, data on clinical manifestations, genotype and the psychosocial ramifications of illness in severely affected females remain anecdotal. A national multi-centre retrospective study was conducted to collect a comprehensive data set on affected US girls and women, and to compare clinical observations to previously published information on haemophilic males of comparable severity and mildly affected haemophilic females. Twenty-two severe/moderate haemophilia A/B subjects were characterized with respect to clinical manifestations and disease complications; genetic determinants of phenotypic severity; and health-related quality of life (HR-QoL). Clinical data were compared as previously indicated. Female patients were older than male patients at diagnosis, but similarly experienced joint haemorrhage, disease- and treatment-related complications and access to treatment. Gynaecological and obstetrical bleeding was unexpectedly infrequent. F8 or F9 mutations, accompanied by extremely skewed X-chromosome inactivation pattern (XIP), were primary determinants of severity. HR-QoL was diminished by arthropathy and viral infection. Using systematic case verification of participants in a national surveillance registry, this study elucidated the genetics, clinical phenotype and quality of life issues in female patients with severe/moderate haemophilia. An ongoing international case-controlled study will further evaluate these observations. Novel mechanistic questions are raised about the relationship between XIP and both age and tissue-specific FVIII and FIX expression.

siRNA targeting prohibitins inhibits proliferation and promotes apoptosis of gastric carcinoma cell line SGC7901 in vitro and in vivo

In the present study we investigate the effects of small interfering RNA (siRNA)-mediated silencing of prohibitins (Phbs) gene expressions on gastric carcinoma cell proliferation and apoptosis in vitro and in vivo. Firstly, Phbs proteins in five human gastric carcinoma cell lines were evaluated by Western blotting. Then three siRNA sequences targeting Phbs were designed and transfected into the cancer cell line with the highest Phbs protein expressions. The cell proliferation and apoptosis were analyzed by MTT and flow cytometry methods. In vivo, the effects of siRNAs on the proliferation and apoptosis were assayed in xenografted tumors of nude mice. Phbs proteins were expressed highest in gastric carcinoma cell line SGC7901. The cell proliferation significantly decreased upon Phbs silencing. The cell percentage in S phase was significantly lower in Phbs silenced groups, and the apoptotic cell ratio was significantly higher. siRNA targeting Phbs significantly inhibited the growth of the xenografted tumors. Further, Bcl-2 and Bax was respectively downregulated and upregulated after the Phbs silencing in the xenografted tumors. Caspase-3 and caspase-9 activities were significantly enhanced in the Phbs-silenced tumors. In summary, siRNA-mediated silencings of Phbs inhibit proliferation and promotes apoptosis of gastric carcinoma cells SGC7901 in vitro and in vivo, suggesting key roles of Phbs in the development of SGC7901 cell line.

Profilin 1 potentiates apoptosis induced by staurosporine in cancer cells

The correlation between the loss of Profilin 1 (Pfn1) with tumor progression indicated that Pfn1 is a tumor suppressor in human carcinoma. The molecular mechanisms underlying Pfn1 tumor suppression has yet to be elucidated. In this study, we showed that Pfn1 overexpression sensitizes cancer cells to apoptosis through the typical intrinsic apoptotic pathway. Mechanistically, the increased Pfn1 expression mediated the upregulation of p53R273H, one of the most common tumor-associated hotspot mutations of p53, with transactivation deletion in tumorigenesis and increased localization of p53R273H in cytoplasm. Further studies showed that mutant p53R273H was involved in apoptosis induced by Staurosporine (STS) via transcription-independent mitochondrial functions. We observed (i) the increased cytosolic localization of p53R273H, (ii) the activation of phosphorylation at Ser15, (iii) its mitochondrial localization; Pfn1 acted as a positive regulator of these processes. We also found that Pfn1 interacted with p53R273H and thus facilitated its exertion over the transcription-independent activity in the cytoplasm during drug action. Our results define a new function and mechanism of Pfn1 demonstrating that the combined effect with apoptotic agents led to a synergistic increase in apoptosis. In addition, p53R273H abrogating DNA binding was found to play a major role in the Pfn1- sensitized apoptosis through a transactivation-independent and cytosolic activity.

Up-regulation of MBD1 promotes pancreatic cancer cell epithelial-mesenchymal transition and invasion by epigenetic down-regulation of E-cadherin

Methyl-CpG binding domain protein 1 (MBD1) has been implicated in transcriptional regulation, heterochromatin formation, genomic stability, cell-cycle progression and development. It is also predicted that MBD1 might be involved in tumor development and progression. However, whether and how MBD1 is involved in tumorigenesis, especially in pancreatic cancer (PC), is currently unknown. We found that MBD1 was significantly up-regulated in PC tissues compared with the surrounding normal tissues according to RT-PCR data. Tissue microarray (TMA) based immunohistochemical study from 58 surgically resected PC specimens indicated that higher MBD1 expression correlated with lymph node metastasis and poor survival in PC patients. Gain- and loss-of-function studies in vitro validated MBD1 as a potent oncogene promoting PC cell invasion as well as epithelial-mesenchymal transition (EMT). Mechanistically, MBD1 is associated with Twist and NAD-dependent deacetylase sirtuin-1 (SIRT1), thereby forming the Twist-MBD1-SIRT1 complex on the CDH1 promoter, which resulted in reduced E-cadherin transcription activity and increased cell EMT ability. Significantly, targeting MBD1 reversed the EMT phenotype of PC and restored sensitivity to chemotherapy. Taken together, the results of our study revealed a novel function of MBD1 in PC invasion and metastasis by providing a molecular mechanism underlying MBD1-promoted EMT. Thus MBD1 may serve as a potential therapeutic target for PC.