Efficacy of Yisui granule(益髓颗粒)on myelodysplastic syndromes in SKM-1 mouse xenograft model through suppressing Wnt/β-catenin signaling pathway

OBJECTIVE:To unmask the underlying mechanisms of Yisui granule(益髓颗粒,YSG)for the treatment of Myelodysplastic syndromes(MDS).METHODS:Our study used an SKM-1 mouse xenograft model of MDS to explore the anti-tumor potential of YSG and its safety,assess its effect on overall survival(OS),and evaluate whether its mechanism is associated with the demethylation of the secreted frizzled related protein 5(s FRP5)gene and suppressing Wnt/β-catenin pathway.Bisulfite amplicon sequencing was applied to detect the level of methylation of the s FRP5 gene;western blotting,immunofluorescence staining,and real-time Polymerase Chain Reaction were performed to detect DNA methyltransferase 1(DNMT1),s FRP5,and other Wnt/β-catenin pathway-related m RNA and protein expression.RESULTS:The results showed that high-dosage YSG exerted an anti-tumor effect similar to that of decitabine,improved OS,and reduced long-term adverse effects in the long term.Mechanically,YSG reduced the expression of DNMT1 methyltransferase,decreased the methylation,and increased the expression of the Wnt/β-catenin pathway antagonist-s FRP5.Furthermore,components of the Wnt/β-catenin pathway,including Wnt3a,β-catenin,c-Myc,and cyclin D1,were down-regulated in response to YSG,suggesting that YSG could treat MDS by demethylating the s FRP5 gene and suppressing the Wnt/β-catenin pathway.CONCLUSIONS:Our findings demonstrated that YSG could be used alone or in combination with decitabine to improve outcomes in the MDS animal model,providing an alternative solution for treating MDS.

Bioinformatic identification of key candidate genes and pathways in axon regeneration after spinal cord injury in zebrafish

Zebrafish and human genomes are highly homologous;however,despite this genomic similarity,adult zebrafish can achieve neuronal proliferation,regeneration and functional restoration within 6–8 weeks after spinal cord injury,whereas humans cannot.To analyze differentially expressed zebrafish genes between axon-regenerated neurons and axon-non-regenerated neurons after spinal cord injury,and to explore the key genes and pathways of axonal regeneration after spinal cord injury,microarray GSE56842 was analyzed using the online tool,GEO2R,in the Gene Expression Omnibus database.Gene ontology and protein-protein interaction networks were used to analyze the identified differentially expressed genes.Finally,we screened for genes and pathways that may play a role in spinal cord injury repair in zebrafish and mammals.A total of 636 differentially expressed genes were obtained,including 255 up-regulated and 381 down-regulated differentially expressed genes in axon-regenerated neurons.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment results were also obtained.A protein-protein interaction network contained 480 node genes and 1976 node connections.We also obtained the 10 hub genes with the highest correlation and the two modules with the highest score.The results showed that spectrin may promote axonal regeneration after spinal cord injury in zebrafish.Transforming growth factor beta signaling may inhibit repair after spinal cord injury in zebrafish.Focal adhesion or tight junctions may play an important role in the migration and proliferation of some cells,such as Schwann cells or neural progenitor cells,after spinal cord injury in zebrafish.Bioinformatic analysis identified key candidate genes and pathways in axonal regeneration after spinal cord injury in zebrafish,providing targets for treatment of spinal cord injury in mammals.

Sonic hedgehog elevates N-myc gene expression in neural stem cells

Proliferation of neural stem cells is regulated by the secreted signaling molecule sonic hedgehog. In this study, neural stem cells were infected with recombinant adeno-associated virus expressing sonic hedgehog-N-enhanced green fluorescent protein. The results showed that overexpression of sonic hedgehog in neural stem cells induced the increased expression of Gill and N-myc, a target gene of sonic hedgehog. These findings suggest that N-myc is a direct downstream target of the sonic hedgehog signal pathway in neural stem cells. Sonic hedgehog and N-myc are important mediators of sonic hedgehog-induced proliferation of neural stem cells.

Epigenetic regulation of Wnt signaling pathway gene SRY-related HMG-box 17 in papillary thyroid carcinoma

Background SRY-related HMG-box 17 （SOX17） encodes a member of the SOX （SRY-related HMG-box） family of transcription factors involved in the regulation of embryonic development and in the determination of the cell fate. Recently, it was considered as a tumor suppressor gene to inhibit canonical Wnt/β-catenin signaling pathway in several malignancies. However, the function of SOX17 in thyroid cancer was unknown. Therefore, we investigated the epigenetic changes and the function of SOX17 in thyroid cancer. Methods The methylation status of the promoter region of SOX17 was detected using methylation-specific PCR in 63 papillary thyroid carcinoma （PTC） tissue, 10 normal thyroid tissue, and two thyroid cancer cell lines. Semi-quantitative RT-PCR was used to assess mRNA expression of SOX17 before and after 5-aza-2＇-deoxycytidine treatment in thyroid cancer cell lines. Expression of SOX17 and β-catenin were detected by immunohistochemistry in PTC and adjacent tissue. Luciferase reporter assay, colony formation, transfection, and Western blotting were employed to analyze the effect of SOX17 on thyroid cancer cell proliferation and the function of SOX17 in the Wnt signal pathway. Results Loss of SOX17 expression was correlated to the promoter region hypermethylation in thyroid cancer cell lines. Re-expression of SOX17 was found in TPC-1 cell line after 5-aza-2＇-deoxycytidine treatment. In primary thyroid cancer, 60.3% （38/63） were methylated and 39.7% （25/63） unmethylated. But no methylation was found in noncancerous thyroid tissues. Methylation of SOX17 was associated reversely with β-catenin expression in the cytoplasm or nucleus significantly in the PTC （P 〈0.05）. Colony formation was inhibited by re-expression of SOX17 in TPC-1 cells. SOX17 suppressed the Wnt signaling pathway and the HMG domain was essential for this effect. Conclusions SOX17 was frequently methylated in human PTC. Loss of SOX17 expression was induced by promoter region hypermethylation. SOX17 inhibited thyroid cancer proliferation. Methylation of SOX17 activated the Wnt signaling pathway in human thyroid cancer.

Research Progress on the Mechanism of Correlation Between Vitamin D and Thyroid Cancer

Vitamin D is a kind of fat-soluble vitamin,which is mainly involved in the metabolism of calcium and bone in the human body.As a metabolic substance,it also has a certain impact on the cellular microenvironment,and vitamin D also inhibits the proliferation of tumor cells.25(OH)D is considered the best index to evaluate the vitamin D level in the human body because of its relatively stable characteristics in the circulation.Thyroid cancer is a common malignant tumor that develops from malignant thyroid nodules.A large number of studies have found that the lower the serum 25(OH)D level,the higher the risk of thyroid nodules.A large number of studies have found that the lower the serum 25(OH)D level,the higher the risk of thyroid nodules.

Epigenetic inactivation of secreted frizzled-related protein 2 in esophageal squamous cell carcinoma

AIM： To investigate the expression and methylation status of the secreted frizzled-related protein 2 （SFRP2） in esophageal squamous cell carcinoma （ESCC） and ex- plore its role in ESCC carcinogenesis.METHODS： Seven ESCC cell lines （KYSE 30, KYSE150, KYSE410, KYSE510, EC109, EC9706 and TE-1） and one immortalized human esophageal epithelial cell line （Het- 1A）, 20 ESCC tissue samples and 20 paired adjacent non-tumor esophageal epithelial tissues were analyzed in this study. Reverse-transcription polymerase chain reaction （RT-PCR） was employed to investigate the expression of SFRP2 in cell lines, primary ESCC tumor tissue, and paired adjacent normal tissue. Methylation status was evaluated by methylation-specific PCR and bisulfite sequencing. The correlation between expres- sion and promoter methylation of the SFRP2 gene was confirmed with treatment of 5-aza-2＇-deoxycytidine. To assess the potential role of SFRP2 in ESCC, we es-tablished stable SFRP2-transfected cells and examined them with regard to cell proliferation, colony formation, apoptosis and cell cycle in vivo and in vitro.RESULTS： SFRP2 mRNA was expressed in the im- mortalized normal esophageal epithelial cell line but not in seven ESCC cell lines. By methylation-specific PCR, complete methylation was detected in three cell lines with silenced SFRP2 expression, and extensive methylation was observed in the other four ESCC cell lines. 5-aza-2＇-deoxycytidine could restore the expres- sion of SFRP2 mRNA in the three ESCC cell lines lack- ing SFRP2 expression. SFRP2 mRNA expression was obviously lower in primary ESCC tissue than in adjacent normal tissue （0.939 ± 0.398 vs 1.51 ± 0.399, P 〈 0.01）. SFRP2 methylation was higher in tumor tissue than in paired normal tissue （95% vs 65%, P 〈 0.05）. The DNA methylation status of the SFRP2 correlated inversely with the SFRP2 expression. To assess the potential role of SFRP2 in ESCC, we established stable SFRP2 transfectants and control counterparts by in- troducing pcDNA3.1/v5 hisA -SFRP2 or pcDNA3.1/v5 hisA -empty vector into KYSE30 cells lacking SFRP2 expression. After transfection, the forced-expression of SFRP2 was confirmed by the RT-PCR. In comparison with the control groups, stably-expressed SFRP2 in KYSE 30 cells significantly reduced colony formation in vitro （47.17% 4± 15.61% vs 17% ：1： 3.6%, P = 0.031） and tumor growth in nude mice （917.86：1：249.35 mm3 vs 337.23 ± 124.43 mm3, P 〈 0.05）. Using flow cytom- etry analysis, we found a significantly higher number of early apoptotic cells in SFRP2-transfected cells than in the control cells （P = 0.025）. The mean cell number in the S and G2-M phases of the cell cycle was also significantly lower in SFRP2-transfected KYSE30 cells compared with mock transfected counterparts. CONCLUSION： Silencing of SFRP2 expression through promoter hypermethylation may be a factor in ESCC carcinogenesis through loss of its tumor-suppressive activity.

Emerging agents that target signaling pathways to eradicate colorectal cancer stem cells

Colorectal cancer(CRC)represents the third most commonly diagnosed cancer and the second leading cause of cancer death worldwide.The modern concept of cancer biology indicates that cancer is formed of a small population of cells called cancer stem cells(CSCs),which present both pluripotency and self-renewal properties.These cells are considered responsible for the progression of the disease,recurrence and tumor resistance.Interestingly,some cell signaling pathways participate in CRC survival,proliferation,and selfrenewal properties,and most of them are dysregulated in CSCs,including the Wingless(Wnt)/β-catenin,Notch,Hedgehog,nuclear factor kappa B(NF-κB),Janus kinase/signal transducer and activator of transcription(JAK/STAT),peroxisome proliferator-activated receptor(PPAR),phosphatidyl-inositol-3-kinase/Akt/mechanistic target of rapamycin(PI3K/Akt/mTOR),and transforming growth factor-β(TGF-β)/Smad pathways.In this review,we summarize the strategies for eradicating CRC stem cells by modulating these dysregulated pathways,which will contribute to the study of potential therapeutic schemes,combining conventional drugs with CSC-targeting drugs,and allowing better cure rates in anti-CRC therapy.

胃复春治疗胃黏膜肠上皮化生的临床观察及机制研究

目的观察胃复春治疗慢性萎缩性胃炎肠上皮化生的病理疗效、中医症状疗效及作用机制。方法将48例慢性浅表性胃炎(CSG)病例及110例胃黏膜肠上皮化生(GIM)病例先分为CSG组与GIM总组,比较两组音猬因子(Shh)/Wnt信号通路蛋白(Wnt3A)表达的不同后,将GIM总组病例随机分为对照组与治疗组,每组55例。对照组口服叶酸片,治疗组在此基础上口服胃复春。两组疗程均为6个月,比较两组GIM病理分级、中医症状疗效和Shh/Wnt3A表达的变化情况。结果 1试验期间,CSG组无脱落;GIM总组脱落21例,最终完成试验者89例。2干预前Shh弱表达于GIM总组,而强表达于CSG组中,组间比较差异有统计学意义(P<0.05);而干预前GIM总组Wnt3A表达明显高于CSG组,组间比较差异有统计学意义(P<0.05)。3组间治疗后比较,GIM分级治疗组较对照组明显改善(P<0.05)。4治疗组、对照组中医症状的总有效率分别为85.42%、36.59%;组间中医症状疗效比较,治疗组明显优于对照组(P<0.05)。组间治疗后比较,中医症状总积分治疗组明显低于对照组(P<0.05)。5组间治疗后比较,Shh表达治疗组明显高于对照组,而Wnt3A表达明显低于对照组(P<0.05)。结论胃复春能较好改善GIM患者中医症状、减轻其病理分级,其机制可能是通过调控Hh-Wnt基因信号通路环来实现的。

MicroRNA changes of bone marrow-derived mesenchymal stem cells differentiated into neuronal-like cells by Schwann cell-conditioned medium

Bone marrow-derived mesenchymal stem cells differentiate into neurons under the induction of Schwann cells. However, key microRNAs and related pathways for differentiation remain unclear. This study screened and identified differentially expressed microRNAs in bone marrow- derived mesenchymal stem cells induced by Schwann cell-conditioned medium, and explored targets and related pathways involved in their differentiation into neuronal-like cells. Primary bone marrow-derived mesenchymal stem cells were isolated from femoral and tibial bones, while primary Schwann cells were isolated from bilateral saphenous nerves. Bone marrow-derived mesenchymal stem cells were cultured in unconditioned (control group) and Schwann cell-conditioned medium (bone marrow-derived mesenchymal stem cell + Schwann cell group). Neuronal differentiation of bone marrow-derived mesenchymal stem cells induced by Schwann cell-conditioned medium was observed by time-lapse imaging. Upon induction, the morphology of bone marrow-derived mesencaymal stem cells changed into a neural shape with neurites. Results of quantitative reverse transcription-polymerase chain reaction revealed that nestin mRNA expression was upregulated from 1 to 3 days and downregulated from 3 to 7 days in the bone marrow-derived mesenchymal stem cell + Schwann cell group. Compared with the control group, microtubule-associated protein 2 mRNA expression gradually increased from 1 to 7 days in the bone marrow-derived mesenchymal stem cell + Schwann cell group. After 7 days of induction, microRNA analysis iden:ified 83 significantly differentially expressed microRNAs between the two groups. Gene Ontology analysis indicated enrichment of microRNA target genes for neuronal projection development, regulation of axonogenesis, and positive regulation of cell proliferation. Kyoto Encyclopedia of Genes and Genomes pathway analysis demonstrated that Hippo, Wnt, transforming growth factor-beta, and Hedgehog signaling pathv/ays were potentially associated with neural differentiation of bone marrow-derived mesenchymal stem cells. This study, which carried out successful microRNA analysis of neuronal-like cells differentiated from bone marrow-derived mesenchymal stem cells by Schwann cell induction, revealed key microRNAs and pathways involved in neural differentiation of bone marrow-derived mesenchymal stem cells. All protocols were approved by the Animal Ethics Committee of Institute of Radiation Medicine, Chinese Academy of Medical Sciences on March 12, 2017 (approval number: DWLI-20170311).

初级纤毛在牙发育中的分布及相关信号通路的研究进展

初级纤毛是位于大多数哺乳动物细胞表面,感受外环境刺激并传导信息的一种细胞器,在组织发育过程中参与调控各种信号通路。本文就初级纤毛在牙发育中的分布及相关信号通路的研究进展作一综述。文献复习结果表明,在牙发育过程中,初级纤毛在上皮与间充质的相互诱导中发挥重要作用,且随细胞不断增殖分化,初级纤毛的分布呈现出时间和空间依赖性。尽管此分布特征的原因尚不明确,但部分实验证据表明其与初级纤毛所分布的细胞与组织的功能相适应。初级纤毛在牙发育过程中主要参与调控Hedgehog和Wnt两种重要的信号通路,编码纤毛蛋白的基因(如Kif3a、Evc/Evc2和Ift等)可通过对这两种信号通路的调控来影响牙齿的发育,并且两种信号通路之间存在交互作用。相关基因(如Ofd1,Bbs等)的缺失也可通过损害纤毛的结构或功能破坏上下游信号的传导,引起多种类型的牙齿发育不良,包括小牙、釉质发育不全、牙齿缺失或颅面部畸形。