CRISPR/Cas9-based genome editing tools have enormous potential for the development of various therapeutic treatments due to their reliability and broad applicability. A central requirement of CRISPR/Cas9 is the efficient intracellular delivery of the editing machinery, which remains a well-recognized challenge, notably to deliver Cas9 in its native protein form. Herein, a phase-separating peptide with intracellular redox-triggered release properties is employed to encapsulate and deliver all three forms of CRISRP-Cas9 editing machinery, namely, pDNA, mRNA/sgRNA, and the ribonucleoprotein complex. These modalities are readily recruited within peptide coacervates during liquid-liquid phase separation by simple mixing and exhibit higher transfection and editing efficiency compared to highly optimized commercially available transfection reagents currently used for genome editing.
Breast cancer is the most common cancer in women in the world. Statistics revealed the number of breast cancer patients less than 40 years of age increased over time. Clinical studies found there is a trend of yearly illness happening in younger patients, whose needs related to the illness are different from older patients. The purpose of this study was to explore the uncertainty and needs of patients in different age groups who were newly diagnosed with breast cancer. A descriptive cross-sectional survey study was adopted to recruit 128 patients. The Mishel’s Uncertainty in Illness Scale (MUIS, Chinese version) and the Cancer Needs Questionnaire (short-form, CNQ-SF) were used to collect data. The results revealed that a patient’s age and religion negatively correlated with illness uncertainty. A patient’s age, educational level, work or not, and children’s age correlated with needs for care. Age, illness uncertainty, and educational level were important predictors of the needs of care, with an explanatory power of 29.0%. In Conclusion, patients ≤40 years of age had greater illness uncertainty and needs for care than those who were >40 years of age. For younger patients newly diagnosed with cancer, medical professionals should take the initiative to provide detailed and complete information on breast cancer treatment plans, prognosis, and home self-care, which helps clarify the possible future treatments and results and further enables patients to acquire self-care skills and knowledge.
We report the transmetallation of hydrocarbyl fragments (Me, Bn, Ph) from a variety of organo-metallic complexes relevant to C-H activation (Ir, Rh, W, Mo) to Pt(II) electrophiles. The scope of suitable hydrocarbyl donors is remarkable in that three different classes of organometallics with widely varying reactivity all undergo the same general reaction with Pt(II) electrophiles. A competitive substituent effect experiment reveals faster transmetallation of more electron rich hydrocarbyl groups. A sterochemical probe reveals that transmetallation to Hg(II) proceeds with retention of stereochemistry. This study suggests that transmetallation could provide a viable path for catalytic function- alization of stable complexes resulting from C-H bond activation and other processes.
Many genetic diseases are caused by single-nucleotide polymorphisms. Base editors can correct these mutations at single-nucleotide resolution, but until recently, only allowed for transition edits, addressing four out of twelve possible DNA base substitutions. Here, we develop a class of C:G to G:C Base Editors to create single-base genomic transversions in human cells. Our C:G to G:C Base Editors consist of a nickase-Cas9 fused to a cytidine deaminase and base excision repair proteins. Characterization of >30 base editor candidates reveal that they predominantly perform C:G to G:C editing (up to 90% purity), with rAPOBEC-nCas9-rXRCC1 being the most efficient (mean 15.4% and up to 37% without selection). C:G to G:C Base Editors target cytidine in WCW, ACC or GCT sequence contexts and within a precise three-nucleotide window of the target protospacer. We further target genes linked to dyslipidemia, hypertrophic cardiomyopathy, and deafness, showing the therapeutic potential of these base editors in interrogating and correcting human genetic diseases.
A significant barrier to harnessing the power of cell-surface glycosaminoglycans (GAGs) to modulate glial cell-line-derived neurotrophic factor (GDNF) signaling is the difficulty in accessing key GAG structures involved. Here, we report tailored GDNF signaling using synthetic polyproline-based GAG mimetics (PGMs). PGMs deliver the much needed proactive programmability for GDNF recognition and effectively modulate GDNF-mediated neuronal processes in a cellular context.
OBJECTIVE:Cholangiocarcinoma (CCA) is a devastating disease. Interferon α-inducible protein 27 (IFI27), originally known to involve in innate immunity, is later found to intervene in cell proliferation, leading to inventive studies regarding the role of IFI27 in cancer treatment. We aimed to investigate the role of IFI27 in CCA. MATERIALS AND METHODS:Cell proliferation, migration, and invasion assays, Western blot, gene transfection and knockdown, immunofluorescent and immunohistochemical stains, and xenograft animal model were applied. RESULTS:IFI27 knockdown in CCA cells induced cell cycle arrest in S phase, resulting in lower cell proliferative rate in vitro and in vivo. IFI27 knockdown attenuated CCA cell migration and invasion through inhibition of epithelial-mesenchymal transition, which was supported by increased E-cadherin and decreased N-cadherin and fibronectin. Filamentous actin level was also reduced. IFI27 knockdown further repressed expression and secretion of vascular endothelial growth factor (VEGF-A), a strong stimulator of angiogenesis, through downregulation of c-jun and c-fos, which was supported in vitro by the finding that human vascular endothelial cells grew more slowly in conditioned medium of IFI27 knockdown on CCA cells and in vivo by the lower erythropoietin concentration found in the xenografted tumors derived from IFI27 knockdown on CCA cells. In addition, anti-VEGF-A antibody treatment was able to repress CCA cell growth. To the contrary, IFI27 overexpression could increase CCA cell proliferation, migration, and invasion. Clinically, higher IFI27 expression was linked to inferior overall survival of CCA patients. CONCLUSION:Our data strongly suggest that IFI27 could be deemed as a potential target for CCA treatment.
BACKGROUND:Breast cancer ranks second in the list of cancer-related deaths for women. Even under multidisciplinary treatment, 25-50% of patients with breast cancer still ultimately develop metastasis, leading to poor prognosis. In addition to inducing angiogenesis, vascular endothelial growth factor-A (VEGF-A) is believed to directly increase cancer cell metastatic potential and overexpression of VEGF-A is associated with higher invasiveness of breast cancer. 1α,25(OH)2D3, the active form of vitamin D, and its analogs have been widely applied as anticancer agents in the past.MATERIAL AND METHODS:Western blot, migration and invasion assays, enzyme-linked immunosorbent assay, and immunofluorescent stain were applied in this study.RESULT:VEGF-A increased cell migration and invasion in estrogen receptor-positive (ER+) breast cancer MCF-7 cells. VEGF-A induced an autocrine loop in MCF-7 cells as VEGF-A treatment increased both VEGF-A expression and secretion. The expression of VEGF receptor type 2 (VEGFR2) and neuropilin 1 was also up-regulated by VEGF-A in MCF-7 cells. In addition, F-actin synthesis and LIM domain kinase 1 (LIMK-1) phosphorylation were increased by VEGF-A. VEGF-A also increased β-catenin expression and nuclear translocation of both β-catenin and nuclear factor-ĸB (NF-ĸB), indicating increased β-catenin and NF-ĸB activity. 1α,25(OH)2D3 and MART-10, an analog of 1α,25(OH)2D3, effectively repressed VEGF-A-induced MCF-7 cell migration and invasion and other VEGF-A-induced effects on MCF-7 cells, with MART-10 being more potent than 1α,25(OH)2D3 Conclusion: MART-10 can be deemed as a promising agent for prevention and treatment of metastasis of ER+ breast cancer with VEGF-A overexpression.
A key limitation of the use of the CRISPR-Cas9 system for genome editing and other applications is the requirement that a protospacer adjacent motif (PAM) be present at the target site. For the most commonly used Cas9 from Streptococcus pyogenes (SpCas9), the required PAM sequence is NGG. No natural or engineered Cas9 variants that have been shown to function efficiently in mammalian cells offer a PAM less restrictive than NGG. Here we use phage-assisted continuous evolution to evolve an expanded PAM SpCas9 variant (xCas9) that can recognize a broad range of PAM sequences including NG, GAA and GAT. The PAM compatibility of xCas9 is the broadest reported, to our knowledge, among Cas9 proteins that are active in mammalian cells, and supports applications in human cells including targeted transcriptional activation, nuclease-mediated gene disruption, and cytidine and adenine base editing. Notably, despite its broadened PAM compatibility, xCas9 has much greater DNA specificity than SpCas9, with substantially lower genome-wide off-target activity at all NGG target sites tested, as well as minimal off-target activity when targeting genomic sites with non-NGG PAMs. These findings expand the DNA targeting scope of CRISPR systems and establish that there is no necessary trade-off between Cas9 editing efficiency, PAM compatibility and DNA specificity.
A high throughput method based on gas chromatography-triple quadrupole mass spectrometry(GC-MS/MS) was established for the determination of 25 kinds of organophosphate esters (OPEs) and phthalate esters(PAEs) compounds in baked foods and plastic packing materials.For baked foods,the samples were ultrasonically extracted with acetonitrile:acetone (8 ∶ 2,by volume),and then purified by QuEChERS with 50 mg C1s and 50 mg PSA.For plastic packaging materials,GC-MS/MS analysis was performed directly after dichloromethane-methanol extraction.All the samples were separated with a DB-5 ms chromatographic column,and detected in selected reaction monitoring (SRM) mode.The correlation coefficients for 25 compounds were not less than 0.997 5,and the method detection limits were in the range of 10-500 μg/kg.The average recoveries(n =6) ranged from 80.2%-119.6% with the RSDs of 1.5%-9.4%.The developed method,with the advantages of easy operation,satisfactory purification effect and favorable matrix effect elimination capacity,was suitable for the determination of OPEs and PAEs in different kinds of baked foods and plastic packing materials.
Cholangiocarcinoma (CCA) is a devastating disease without effective treatments. 1α,25(OH)2D3, the active form of Vitamin D, has emerged as a new anti-cancer regimen. However, the side effect of hypercalcemia impedes its systemic administration. 25(OH)D is biologically inert and needs hydroxylation by CYP27B1 to form 1α,25(OH)2D3, which is originally believed to only take place in kidneys. Recently, the extra-renal expression of CYP27B1 has been identified and in vitro conversion of 25(OH)D to 1α,25(OH)2D3 has been found in some cancer cells with CYP27B1 expression. In this study, CYP27B1 expression was demonstrated in CCA cells and human CCA specimens. 25(OH)D effectively represses SNU308 cells growth, which was strengthened or attenuated as CYP27B1 overexpression or knockdown. Lipocalcin-2 (LCN2) was also found to be repressed by 25(OH)D. After treatment with 800 ng/mL 25(OH)D, the intracellular 1α,25(OH)2D3 concentration was higher in SNU308 cells with CYP27B1 overexpression than wild type SNU308 cells. In a xenograft animal experiment, 25(OH)D, at a dose of 6 μg/kg or 20 μg/kg, significantly inhibited SNU308 cells’ growth without inducing obvious side effects. Collectively, our results indicated that SNU308 cells were able to convert 25(OH)D to 1α,25(OH)2D3 and 25(OH)D CYP27B1 gene therapy could be deemed as a promising therapeutic direction for CCA.
BACKGROUND/AIM:Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) insufficiency is commonly found in breast cancer patients with metastasis. We investigated the mechanisms by which PTEN affects breast cancer metastatic behavior.MATERIALS AND METHODS:Migration and invasion assay, western blot, immunofluorescent staining and zebrafish animal model were applied.RESULTS:We showed that PTEN insufficiency induced an increase in MCF-7 cell migration and invasion through induction of epithelial-mesenchymal transition (EMT), which was triggered by up-regulation of the EMT-inducing transcriptional factors Zeb1, Zeb2, Snail, Slug and Twist. Simultaneously, E-cadherin expression was inhibited and P-cadherin was up-regulated. Further, WNT1 inducible signaling pathway protein 1 (WISP1) and lipocalin-2 (LCN2) expressions were increased after PTEN knockdown in MCF-7 cells, which also exhibited increased filamentous actin (F-actin) synthesis and extracellular matrix metalloproteinase-2 (MMP-2) and MMP-9 expression. We further showed that PTEN knockdown in MCF-7 cells could increase cell migration in the xenograft zebrafish model.CONCLUSION:Our findings reveal new therapeutic targets for breast cancer patients with PTEN insufficiency.
Regarding breast cancer treatment, triple negative breast cancer (TNBC) is a difficult issue. Most TNBC patients die of cancer metastasis. Thus, to develop a new regimen to attenuate TNBC metastatic potential is urgently needed. MART-10 (19-nor-2α-(3-hydroxypropyl)-1α,25(OH)2D3), the newly-synthesized 1α,25(OH)2D3 analog, has been shown to be much more potent in cancer growth inhibition than 1α,25(OH)2D3 and be active in vivo without inducing obvious side effect. In this study, we demonstrated that both 1α,25(OH)2D3 and MART-10 could effectively repress TNBC cells migration and invasion with MART-10 more effective. MART-10 and 1α,25(OH)2D3 induced cadherin switching (upregulation of E-cadherin and downregulation of N-cadherin) and downregulated P-cadherin expression in MDA-MB-231 cells. The EMT(epithelial mesenchymal transition) process in MDA-MB-231 cells was repressed by MART-10 through inhibiting Zeb1, Zeb2, Slug, and Twist expression. LCN2, one kind of breast cancer metastasis stimulator, was also found for the first time to be repressed by 1α,25(OH)2D3 and MART-10 in breast cancer cells. Matrix metalloproteinase-9 (MMP-9) activity was also downregulated by MART-10. Furthermore, F-actin synthesis in MDA-MB-231 cells was attenuated as exposure to 1α,25(OH)2D3 and MART-10. Based on our result, we conclude that MART-10 could effectively inhibit TNBC cells metastatic potential and deserves further investigation as a new regimen to treat TNBC.
BACKGROUND Neuroendocrine tumors (NETs) are the second most common digestive malignancy. For advanced NETs, survival is not satisfactory. Vitamin D has emerged as a promising anticancer drug. MATERIALS AND METHODS Cell proliferation assay, western blot, flow cytometry, and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assays were applied. RESULTS We demonstrated that RIN-m cells, neuroendocrine tumor cells, expressed vitamin D receptor (VDR) and VDR expression increased with increasing exposure to 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3] or MART-10, a 1α,25(OH)2D3 analog. MART-10 had anti-growth effect on RIN-m cells comparable to those of 1α,25(OH)2D3 The growth inhibition of both drugs was mediated by induction of cell-cycle arrest at G0/G1 phase and apoptosis. Western blot assay further revealed that this G0/G1 arrest was due to the up-regulation of p27 and down-regulation of cyclin dependent kinase 4 (CDK4), with MART-10 also reducing CDK6. Apoptosis induction was further supported by increased cleaved caspase-3 expression after treatment. CONCLUSION MART-10 appears to be a promising regimen for NET treatment.
超声萃取结合超高效液相色谱(UPLC)技术,建立了食品塑料包装材料中14种紫外吸收剂及抗氧化剂(UV-0,UV-9,UV-71,UV-329,UV-326,UV-327,UV-234,UV-360,抗氧化剂2246,抗氧化剂425,TH-1790,抗氧化剂3114,抗氧化剂1010和抗氧化剂1076)的高通量检测方法.样品经三氯甲烷-甲醇超声提取,C18色谱柱分离后,乙腈和0.1%甲酸水为流动相梯度洗脱,二极管阵列检测器测定.14种物质在一定的浓度范围内线性关系良好,相关系数(r2)均不低于0.999 2,方法定量下限(S/N=10)为8.0~33.0 mg/kg,平均回收率为83.6% ~ 116.2%,相对标准偏差(RSD,n=6)为1.3% ~9.5%.方法具有前处理简单、净化效果好等特点,适用于食品塑料包装中14种紫外吸收剂及抗氧化剂的同时测定.
A proof-of-principle demonstration of a one-way polarization encoding quantum key distribution (QKD) system is demonstrated. This approach can automatically compensate for birefringence and phase drift. This is achieved by constructing intrinsically stable polarization-modulated units (PMUs) to perform the encoding and decoding, which can be used with four-state protocol, six-state protocol, and the measurement-device-independent (MDI) scheme. A polarization extinction ratio of about 30 dB was maintained for several hours over a 50 km optical fiber without any adjustments to our setup, which evidences its potential for use in practical applications.
产品质量安全风险监测是质监部门严把质量安全关的望远镜和探照灯。它是政府部门产品质量监督工作的重要组成部分,风险监测和监督抽查双轮驱动,互相补充,是目前质监部门进行质量安全监管的两大利器,在保证产品质量安全方面发挥着无可替代的作用。风险监测工作也一直是广东省广州市质量监督检测研究院重点发展的方向,院领导高度重视,不断完善各项制度,为风险监测保驾护航。同时在技术力量、研究资
Background: Angiogenesis is the hall marker for cancer growth and metastasis. Thus, anti-angiogenesis emerges as a new way to treat cancer. 1 alpha,25(OH)(2)D-3 is recently getting popular due to the non-mineral functions, which have been applied fore cancer treatment. The newly-synthesized 1 alpha,25(OH)(2)D-3 analog, MART-10, has been proved to be much more potent than 1 alpha,25(OH)(2)D-3 regarding inhibiting cancer cells growth and metastasis without inducing hypercalcemia in vivo. In this study, we aimed to investigate the effect of MART-10 and 1 alpha,25(OH)(2)D-3 on angiogenesis in vitro and in vivo.Methods and results: MART-10 and 1 alpha,25(OH)(2)D-3 were able to repress VEGFA-induced human umbilical vein endothelial cells (HUVECs) migration, invasion and tube formation, but not proliferation, with MART-10 much more potent than 1 alpha,25(OH)(2)D-3. The Chick Chorioallantoic Membrane (CAM) assay and matrigeal angiogenesis assay further confirmed the in vivo more potent anti-angiogenesis effect of MART-10. MART-10 inhibited the VEGFA-induced HUVECs angiogenesis process through downregulation of Akt and Erk 1/2 phosphorylation. The VEGFA-VEGFR2 (VEGF receptor 2) axis is the main signal transducing pathway to stimulate angiogenesis. A positive autocrine manner was found for the first time in HUVECs as treated by VEGFA, which induced VEGFA expression and secretion, and VEGFR2 expression. MART-10 and1 alpha,25(OH)(2)D-3 were demonstrated to be able to repress this positive autocrine manner, thus inhibiting angiogenesis.Conclusions: MART-10 and 1 alpha,25(OH)(2)D-3 both are effective anti-angiogenesis agents. Given MART-10 is much more potent than 1 alpha,25(OH)(2)D-3 and active in vivo without obvious side effect, MART-10 should be deemed as a promising anti-cancer agent. (C) 2015 Elsevier Ltd. All rights reserved.
Phosphatase and tensin homolog (PTEN), a well-known tumor suppressor gene and frequently mutated or lost in breast cancer, possesses the negative regulation function over the PI3K/Akt/mTOR pathway. PTEN insufficiency has been associated with advanced breast cancer and poor prognosis of breast cancer patients. Recently, target therapies aimed at PI3K/Akt/mTOR pathway to treat breast cancer have got popularity. However, the exact effect of PTEN on breast cancer cells is still not well understood. This study demonstrated that PTEN knockdown in MCF-7 cells strengthened the downstream gene expressions, including p-Akt, p-ERK1/2, p-mTOR, p-p70s6k, and p-GSK3β. PTEN knockdown MCF-7 cells had increased cell growth and Ki-67 expression. Further Western blot demonstrated that p27 was repressed obviously with p21 slightly inhibited and CDK1, 2, 4, 6, cyclin A, and Cdc25C were upregulated in MCF-7 PTEN knockdown cells, leading to the higher growth rate. More importantly, PTEN knockdown MCF-7 cells had higher tumorigenesis and tumor growth in vivo. From our current work, we provided more detailed PTEN-mediated mechanisms to stimulate ER+ breast cancer cell growth. Our result may pave the way for further target therapy development used alone or in combination with other drugs for ER+ breast cancer with PTEN insufficiency.
Hepatocellular carcinoma (HCC) is the most diagnosed liver cancer without effective treatments available for advanced HCC. Vitamin D is getting popular due to its anti-cancer characteristics. However, the clinical application of 1α,25(OH)2D, the active form of vitamin, is hampered by its hypercalcemia side effect. 1α,25(OH)2D is converted from 25(OH)D, the index of serum vitamin D status, by CYP27B1, which is originally found in kidneys but recently detected in non-renal tissues. 25(OH)D has been shown to repress some cancers expressing CYP27B1 due to the local conversion of 25(OH)D to 1α,25(OH)2D, which works in a intra-, auto-, or paracrine manner and thus minimizes the risk of hypercalcemia. In this study, we found CYP27B1 expression in human hepatocyte, HCC, and HepG2 cells. As we treated HepG2 cells with 25(OH)D, the 1α,25(OH)2D target gene CYP24A1 expression was increased and was further upregulated as CYP27B1 transfection or downregulated as CYP27B1 knockdown. Other 1α,25(OH)2D target genes in HepG2 cells, p21 and p27 were also stimulated by 25(OH)D after CYP27B1 transfection. Further, 25(OH)D could inhibit HepG2 cells growth, which was potentiated by CYP27B1 transfection. Collectively, we showed for the first time that HCC expressed CYP27B1 and was able to covert 25(OH)D to 1α,25(OH)2D in vitro, thus responsive to 25(OH)D treatment. Our data justifies the application of 25(OH)D and CYP27B1 gene transfection therapy in further HCC treatment studies.
The survival rate of anaplastic thyroid cancer (ATC) is still very poor due to its fast growth and high metastatic potential. Currently, no effective treatment is available. The active form of vitamin D3, 1α,25(OH)2D3, has been shown to have a anti-metastatic effect in pre-clinical studies, however induction of hypercalcemia hampered its clinical application. The new class of less-calcemic vitamin D analog, 19-nor-2α-(3-hydroxypropyl)-1α,25-dihydroxyvitamin D3 (MART-10), is much more potent than 1α,25(OH)2D3 to repress cancer growth and metastasis in a variety of cancers. In this study, we demonstrated that both 1α,25(OH)2D3 and MART-10 could effectively inhibit the migration and invasion of ATC cells, 8305C and 8505C, with MART-10 much more potent than 1α,25(OH)2D3. The anti-metastatic effect of 1α,25(OH)2D3 and MART-10 on ATC cells is mediated by reversal of cadherin switch (upregulation of E-cadherin and downregulation of N-cadherin), which led to the attenuation of EMT process, and decrease of F-actin formation. We further showed that the expressions of Slug, the EMT-related transcriptional factor, and MMP-9 were inhibited by 1α,25(OH)2D3 and MART-10 in 8505C cells, but not in 8303C cells. Since metastasis is the important cause of ATC-related death, our results strongly encourage the further in vivo study of MART-10 application against ATC.