PAK5-Egr1-MMP2 signaling controls the migration and invasion in breast cancer cell

p21-activated kinases (PAKs) are activated by various extracellular stimuli and, in turn, activate other kinases by phosphorylating them at specific serine/threonine residues or through protein–protein interaction. As a recently identified member of the group B PAK family, the role of PAK5 in cancer is poorly understood. In this study, we investigated the effect of PAK5 on the malignant phenotype, such as proliferation, cell cycle, apoptosis, migration, and invasion. Cell growth assay and cell cycle analysis consistently showed that knockdown of PAK5 could significantly inhibit the proliferation of breast cancer cells. Wound healing assay. migration assay, and invasion assay showed that PAK5 promoted cell migration. Furthermore, in order to elucidate the underlying mechanism of PAK5 on cellular growth and migration, we examined the protein expressions of cyclin D1, p21, early growth response protein 1 (Egr1), and matrix metalloproteinase 2 (MMP2). Our work further reveals the PAK5-Egr1-MMP2 signaling pathway to be a critical regulator of cell migration and invasion. These results suggest that PAK5 may be a potential therapeutic target for breast cancer.     

ADAM10 overexpression in human non-small cell lung cancer correlates with cell migration and invasion through the activation of the Notch1 signaling pathway

A disintegrin and metalloproteinase 10 (ADAM10) was identified as a key protease in the ectodomain shedding of various substrates, such as Notch1 protein, ErbB2 and E-cadherin, which are important in the development of non-small cell lung cancer (NSCLC). The aim of this study was to investi-gate the role of ADAM10 in NSCLC metastasis.We characterized the expression of ADAM10 and Notch1 in human NSCLC tissues in?vivo. Immunohistochemical analysis indicated that ADAM10 expression was significantly increased in the NSCLC tissues, particularly in the metastatic tissues. Futhermore, ADAM10 overexpression positively correlated with Notch1 expression in the NSCLC tissues. The in?vitro downregulation of ADAM10 expression using ADAM10 short hairpin RNA (shRNA) reduced the migration and invasion of NSCLC cells. We present further evidence that ADAM10 promotes NSCLC cell migration and invasion via the activation of the Notch1 signaling pathway. Taken together, our results suggest that ADAM10 may serve as a potential target for the therapeutic intervention of NSCLC metastasis. The data provided in this study may aid in the further understanding of the function of ADAM10 in the progression of NSCLC and open new perspectives for the diagnosis and treatment of NSCLC.     

Up-regulation of C1GALT1 promotes breast cancer cell growth through MUC1-C signaling pathway

Aberrant glycosylation is frequently observed in cancers. Core 1 β1,3-galactosyltransferase (C1GALT1) is an exclusive enzyme in humans that catalyzes the biosynthesis of core 1 O-glycan structure, Gal-GalNAc-O-Ser/Thr, whose expression is commonly up-regulated during tumorigenesis. Little is known about the function of C1GALT1 in breast cancer. This study aims to determine the correlation between C1GALT1 expression and breast cancer clinicopathological features and roles of C1GALT1 in breast cancer malignant phenotypes. Public databases and our data showed that C1GALT1 mRNA and C1GALT1 protein are frequently up-regulated in breast cancer; and increased C1GALT1 expression correlates with higher histological grade and advanced tumor stage. Overexpression of C1GALT1 enhanced breast cancer cell growth, migration, and invasion in vitro as well as tumor growth in vivo. Conversely, C1GALT1 knockdown suppressed these malignant phenotypes. Furthermore, C1GALT1 modulates O-glycan structures on Mucin (MUC) 1 and promotes MUC1-C/β-catenin signaling in breast cancer cells. These findings suggest that C1GALT1 enhances breast cancer malignant progression through promoting MUC1-C/β-catenin signaling pathway. Unveiling the function of C1GALT1 in breast cancer opens new insights to the roles of C1GALT1 and O-glycosylation in tumorigenesis and renders the potential of C1GALT1 as a target of novel therapeutic agent development.     

FMNL2通过Rho信号通路促进胃癌细胞的侵袭和迁移

目的:研究同源形成素样蛋白2（FMNL2）是否通过Rho信号通路促进胃癌细胞的侵袭和迁移。方法:利用Oncomine数据库中的大数据分析FMNL2在胃癌及癌旁组织中的表达水平。运用实时定量聚合酶链反应（RT-PCR）和蛋白质印迹法（Western blot）检测胃癌细胞系中FMNL2 mRNA和蛋白的表达情况,使用shFMNL2质粒和空载质粒转染胃癌细胞系,并分为敲减组和对照组。采用 CCK8法、划痕实验、Transwell侵袭实验分析细胞的生物学功能,包括增殖、迁移及侵袭能力,利用Western blot方法检测两组细胞经Rho信号通路抑制剂Y27632处理后的E-cadherin、Vimentin及Rho信号通路相关蛋白的表达情况。结果:经生物信息学分析发现FMNL2在胃癌组织中高表达。同样FMNL2在胃癌细胞中表达水平升高。划痕实验和Transwell侵袭实验结果表明敲减组的迁移和侵袭能力显著下降。Western blot结果显示与对照组相比,E-cadherin在敲减组表达上调,Vimentin、RhoA、ROCK在敲减组表达下调。加入通路抑制剂Y27632后,EMT相关蛋白表达可被逆转。结论:下调FMNL2的表达可抑制胃癌细胞的侵袭迁移能力,并且可通过抑制Rho信号通路来实现。     

CDO1通过PI3K/AKT信号通路调控胃癌细胞增殖及细胞周期

目的:探讨半胱氨酸双加氧酶1(CDO1)对胃癌细胞增殖、细胞周期的调控机制。方法:用脂质体法将si-NC组（转染si-NC）、si-CDO1组（转染si-CDO1）、pcDNA组（转染pcDNA）、pcDNA-CDO1组（转染pcDNA-CDO1）、pcDNA-CDO1+DMSO组（转染pcDNA-CDO1并用DMSO处理）、pcDNA-CDO1+IGF-1组（转染pcDNA-CDO1并用IGF-1处理）转染至AKG细胞。用实时荧光定量逆转录聚合酶链反应（qRT-PCR）、免疫印迹（Western blot）、细胞计数试剂盒（CCK-8）、流式细胞术检测细胞CDO1、PI3K、Akt、p-Akt蛋白的表达、细胞增殖、细胞周期。结果:与人胃黏膜上皮细胞GES-1相比,胃腺癌细胞AKG中CDO1的表达明显降低（P<0.05）;与si-NC组相比,si-CDO1组AKG细胞的增殖明显上调,细胞发生明显的S期、G2/M期阻滞,过表达CDO1则具有相反的作用。重要的是,敲减CDO1可上调PI3K/AKT信号通路关键基因PI3K、p-Akt的表达,而过表达CDO1具有相反的作用。激活PI3K/AKT信号通路后,过表达CDO1对胃癌细胞的增殖、细胞周期的调控作用可被部分逆转。结论:CDO1可抑制胃癌细胞的增殖,调控细胞周期,其机制与抑制PI3K/AKT信号通路的活性有关,将为胃癌的治疗提供参考。     

Notch信号转导通路与原发性肝癌

Notch信号转导通路由一组在进化上高度保守的细胞膜配体、受体及下游分子组成。细胞间受体配体作用可激活Notch信号转导过程,从而直接调节基因转录,使细胞基因表达受相邻细胞调控,Notch信号在细胞分化、胚胎发育、组织自我更新过程中均发挥了重要的作用,许多病理过程（包括肿瘤）都有Notch信号参与。Notch信号多作为癌基因促进肿瘤生长,但在某些组织也可起到诱导细胞分化、抑制肿瘤增殖的作用。肿瘤干细胞中Notch信号的改变可能发挥了关键性作用。目前认为,Notch在肝癌中作为抑癌基因抑制肿瘤的生长,其机制初步被认为是Notch1使JNK活化、p53高表达以及Bcl2表达下调,从而诱导肝癌细胞凋亡,但尚待更加深入的研究。鉴于针对Notch信号通路的干预措施已经成为治疗肿瘤的新方式,该通路也有望成为肝癌的生物治疗新的靶点。     

CTHRC1通过活化FAK-ERK1/2信号通路促进膀胱癌5637细胞迁移和侵袭

目的：探讨胶原三螺旋重复蛋白1(CTHRC1)在膀胱癌组织和细胞中的表达及其对膀胱癌5637细胞迁移和侵袭的影响及其机制。方法：利用TCGA和Arrayexpress数据库中膀胱癌基因表达数据,分析CTHRC1转录和翻译水平。收集2014年9月至2020年12月重庆医科大学附属第一医院手术切除的144例膀胱癌组织和25例全膀胱切除的癌旁组织标本,以及人膀胱癌细胞RT4、5637、T24、UMUC-3、TCCSUP和输尿管上皮永生化细胞SV-HUC-1。采用免疫组织化学染色法、qPCR法和WB法检测膀胱癌组织和细胞中CTHRC1的表达水平,通过Kaplan-Meier曲线分析CTHRC1表达对总生存期（OS）的影响。运用RNAi技术,敲降5637细胞CTHRC1表达后,通过细胞划痕实验和Transwell实验检测CTHRC1表达下调对5637细胞迁移和侵袭的影响。利用基因集富集分析（GSEA）预测CTHRC1相关的潜在信号通路,WB法检测敲降CTHRC1表达对FAK-ERK1/2通路相关蛋白表达的影响。结果：CTHRC1的转录和翻译水平在肌层浸润性膀胱癌（MIBC）组织和细胞中表达显著上...     

Peroxiredoxin 1 controls prostate cancer growth through Toll-like receptor 4-dependent regulation of tumor vasculature

In recent years a number of studies have implicated chronic inflammation in prostate carcinogenesis. However, mitigating factors of inflammation in the prostate are virtually unknown. Toll-like receptor 4 (TLR4) activity is associated with inflammation and is correlated with progression risk in prostate cancer (CaP). TLR4 ligands include bacterial cell wall proteins, danger signaling proteins, and intracellular proteins such as heat shock proteins and peroxiredoxin 1 (Prx1). Here we show that Prx1 is overexpressed in human CaP specimens and that it regulates prostate tumor growth through TLR4-dependent regulation of prostate tumor vasculature. Inhibiting Prx1 expression in prostate tumor cells reduced tumor vascular formation and function. Furthermore, Prx1 inhibition reduced levels of angiogenic proteins such as VEGF within the tumor microenvironment. Lastly, Prx1-stimulated endothelial cell proliferation, migration, and differentiation in a TLR4- and VEGF-dependent manner. Taken together, these results implicate Prx1 as a tumor-derived inducer of inflammation, providing a mechanistic link between inflammation and TLR4 in prostate carcinogenesis. Our findings implicate Prx1 as a novel therapeutic target for CaP.     

TRPM7 mediates breast cancer cell migration and invasion through the MAPK pathway

Metastasis is an inherent feature of breast cancer and transient receptor potential (TRP) channels were found to be potentially implicated in this process. Particularly, TRPM7 may regulate cell motility. We therefore examined the expression of TRPM7 mRNA in the Oncomine database and found that TRPM7 is correlated to metastasis and invasive breast cancer. Silencing TRPM7 with RNA interference resulted in a significant decrease in migration and invasion capability of MDA-MB-435 breast cancer cells, and phosphorylation levels of Src and MAPK but not AKT. Our results suggest that TRPM7 regulates migration and invasion of metastatic breast cancer cells via MAPK pathway.     

Characterization of TRIP6-dependent nasopharyngeal cancer cell migration

Nasopharyngeal carcinoma (NPC) is a leading malignancy most often reported in endemic areas such as in Southeast Asia and the Mediterranean area. NPC remains as a major challenge for clinical management largely due to its high propensity for cancer invasion, metastasis, and recurrence. Therefore, control of NPC cell motility stands as a major obstacle for successful NPC management. The current study sought to identify a new regulator for NPC cell motility in light of previous data showing a similar role of thyroid receptor interactor protein 6 (TRIP6) in other cancer cell types. Results showed that TRIP6 is up-regulated in NPC cells as compared to normal nasopharyngeal epithelial cells. Moreover, TRIP6 overexpression/knockdown results in significant enhancement/inhibition of NPC cell migration, respectively. Interestingly, data also suggested that TRIP6 Y55E (tyrosine 55 to glutamic acid) mutant can promote cell migration more efficiently than wild type does, while Y55A (tyrosine 55 to alanine) mutant has no effects on cell migration as demonstrated with different methodology. Consistently, we also found that c-Src physically interacts with TRIP6, which suggests its potential role as a TRIP6 kinase. Taken together, these data suggested that TRIP6 is involved in the regulation of NPC cell motility, and phosphorylation of tyrosine 55 residue plays an important regulatory role for this event. These data highlight the importance of TRIP6 as a novel regulator of NPC cell motility, which warrants a good basis for further investigation on the underlying mechanism by which TRIP6 exerts this effect and the pathophysiological role TRIP6 plays in vivo.     

人参皂苷Rh2通过Egr-1/TRL4/mTOR信号通路抑制食管癌细胞Eca-109增殖、迁移和EMT

目的:研究人参皂苷Rh2对食管癌细胞Eca-109增殖、迁移和上皮间质转化（epithelial-mesenchymal transition,EMT）的作用以及作用机制。方法:CCK-8法检测人参皂苷Rh2对食管癌细胞Eca-109增殖的影响;细胞划痕实验检测人参皂苷Rh2对食管癌Eca-109细胞迁移的影响;Western blot检测EMT相关蛋白E-cadherin、Vimentin和Slug的蛋白表达水平。结果:人参皂苷Rh2能够显著抑制Eca-109细胞的增殖,且呈剂量依赖性;此外,人参皂苷Rh2显著抑制E-cadherin、Vimentin和Slug的蛋白表达,并抑制Eca-109细胞迁移;人参皂苷Rh2显著抑制Egr-1、TRL4和mTOR的蛋白表达;进一步的研究结果表明人参皂苷Rh2通过抑制Egr-1/TRL4/mTOR信号通路抑制食管癌细胞Eca-109增殖、迁移和EMT。结论:人参皂苷Rh2能够抑制食管癌细胞Eca-109的增殖、迁移和EMT,其作用机制是通过介导Egr-1/TRL4/mTOR信号通路来实现的。这一结果能够为治疗食管癌的进一步研究提供分子基础。     

PAK1-dependent MAPK pathway activation is required for colorectal cancer cell proliferation

P21-activated protein kinase1 (PAK1), a main downstream effector of small Rho GTPases, Rac1, and Cdc42, plays an important role in the regulation of cell morphogenesis, motility, mitosis, and angiogenesis. Despite its importance, the molecular mechanisms of PAK1 that contributed to colorectal carcinogenesis remain unclear. Our immunohistochemistry showed that PAK1 expression was increased with colorectal cancer (CRC) progression through the adenoma to carcinoma sequence. Furthermore, our results suggested a relationship between PAK1 nuclear localization and the Dukes staging. In the present study, we showed that PAK1 knockdown decreased proliferation and delayed the G1/S cell-cycle transition, and increased apoptosis in vivo and in vitro. In addition, PAK1 knock-down downregulated c-Jun amino terminal kinases (JNK) activity and the levels of cyclinD1, CDK4/6. Inhibition of the JNK activity by chemical inhibitor (SP600125) significantly reduced the effects of PAK1 on CRC proliferation via accumulation of phosphatase and tensin homolog deleted on chromosome 10 (PTEN). In conclusion, our results demonstrate that knockdown of PAK1 could enhance the chemosensitivity of CRCs to 5-fluorouracil through G1 arrest. The mechanism by which PAK1 induced cancer growth might involve activation of JNK as well as downregulation of PTEN. Targeting PAK1 may represent a novel treatment strategy for developing novel chemotherapeutic agents.     

Wnt信号转导通路与肿瘤干细胞

随着肿瘤干细胞学说的证实,调节干细胞自我更新及分化功能的信号调节网络越来越成为研究的热点.在复杂的结节网络中,Wnt信号通路的作用日益突出,对该信号通路的生物学行为的了解有利于深入了解肿瘤干细胞,也有利于针对肿瘤干细胞的分子靶向治疗的研究.本文就有关wnt信号通路在这方面的研究进展作一综述.     

TRPV3 inhibits colorectal cancer cell proliferation and migration by regulating the MAPK signaling pathway

BackgroundThe aim of this study was to investigate the inhibiting effect of transient receptor potential vanilloid 3 (TRPV3) on the proliferation and migration of colorectal cancer (CRC) cells and to explore the underlying mechanism.MethodsA microarray dataset from the publicly available Gene Expression Omnibus (GEO) database was used to investigate the prognostic value of TRPV3 in CRC. In addition, 100 CRC tissue samples were collected at our center to further validate its prognostic value at the protein level. Cell proliferation ability was detected by Cell Counting Kit-8 (CCK-8) assay, and cell migration ability was detected by transwell assay. Gene set variation analysis (GSVA) was performed to identify the potential pathways regulated by TRPV3.ResultsBased on the largest microarray dataset ({"type":"entrez-geo","attrs":{"text":"GSE39582","term_id":"39582"}}GSE39582), low expression of TRPV3 was found to be significantly associated with poor prognosis in CRC patients, and this result was successfully validated at our cancer center. Functional experiments showed that knockdown of TRPV3 enhanced cell proliferation and migration, while enforced TRPV3 expression exhibited the opposite effect. GSEA based on public microarray data revealed that the mitogen-activated protein kinase (MAPK) signaling pathway was notably activated in patients with low expression of TRPV3. Further experiments in vivo confirmed that TRPV3 silencing promoted cell proliferation and migration by activating the MAPK signaling pathway.ConclusionsLow expression of TRPV3, which stimulates cell proliferation and migration by provoking the MAPK signaling pathway, indicated poor prognosis in CRC patients.     

Resveratrol suppresses cell transformation and induces apoptosis through a p53-dependent pathway

Resveratrol, a plant constituent enriched in the skin of grapes, is one of the most promising agents for the prevention of cancer. However, the mechanism of the anti-carcinogenic activity of resveratrol is not well understood. Here we offer a possible explanation of its anti-cancer effect. Resveratrol suppresses tumor promoter-induced cell transformation and markedly induces apoptosis, transactivation of p53 activity and expression of p53 protein in the same cell line and at the same dosage. Also, resveratrol-induced apoptosis occurs only in cells expressing wild-type p53 (p53+/+), but not in p53-deficient (p53-/-) cells, while there is no difference in apoptosis induction between normal lymphoblasts and sphingomyelinase-deficient cell lines. These results demonstrate for the first time that resveratrol induces apoptosis through activation of p53 activity, suggesting that its anti-tumor activity may occur through the induction of apoptosis.     

Vascular endothelial growth factor regulates myeloid cell leukemia-1 expression through neuropilin-1-dependent activation of c-MET signaling in human prostate cancer cells

Background

Nuclear factor-κB (NF-κB) is constitutively activated in many cancers and plays a key role in promoting cell proliferation, survival, and invasion. Our understanding of NF-κB signaling in thyroid cancer, however, is limited. In this study, we have investigated the role of NF-κB signaling in thyroid cancer cell proliferation, invasion, and apoptosis using selective genetic inhibition of NF-κB in advanced thyroid cancer cell lines.

Results

Three pharmacologic inhibitors of NF-κB differentially inhibited growth in a panel of advanced thyroid cancer cell lines, suggesting that these NF-κB inhibitors may have off-target effects. We therefore used a selective genetic approach to inhibit NF-κB signaling by overexpression of a dominant-negative IκBα (mIκBα). These studies revealed decreased cell growth in only one of five thyroid cancer cell lines (8505C), which occurred through a block in the S-G2/M transition. Resistance to TNFα-induced apoptosis was observed in all cell lines, likely through an NF-κB-dependent mechanism. Inhibition of NF-κB by mIκBα sensitized a subset of cell lines to TNFα-induced apoptosis. Sensitive cell lines displayed sustained activation of the stress-activated protein kinase/c-Jun NH2-terminal kinase (SAPK/JNK) pathway, defining a potential mechanism of response. Finally, NF-κB inhibition by mIκBα expression differentially reduced thyroid cancer cell invasion in these thyroid cancer cell lines. Sensitive cell lines demonstrated approximately a two-fold decrease in invasion, which was associated with differential expression of MMP-13. MMP-9 was reduced by mIκBα expression in all cell lines tested.

Conclusions

These data indicate that selective inhibition of NF-κB represents an attractive therapeutic target for the treatment of advanced thyroid. However, it is apparent that global regulation of thyroid cancer cell growth and invasion is not achieved by NF-κB signaling alone. Instead, our findings suggest that other important molecular processes play a critical role in defining the extent of NF-κB function within cancer cells.     

Fas通路通过激活ERK1/2通路在结肠癌细胞中诱导上皮-间质转化

  目的   探索Fas通路在结肠癌细胞中诱导上皮间质转化(epithelial-mesenchymal transition, EMT)的分子机制。   方法   分别对结肠癌细胞SW480及DLD1予以低剂量FasL(12.5 ng/mL)处理。作用3d后分别提取实验组和对照组细胞的总蛋白、总RNA, 并进行Western blot、RT-PCR检测, 分析FasL作用下结肠癌细胞的上皮标记物、间质标记物以及EMT相关的转录因子的表达状况。在低剂量FasL作用3d后行免疫荧光检测, 观察EMT相关转录因子在细胞内的分布情况。建立稳定敲除Snail及Twist的结肠癌细胞系, 再予以低剂量FasL刺激, 采用Western blot、RT-PCR检测是否发生EMT过程。对结肠癌细胞SW480予以低剂量FasL(12.5 ng/mL)处理后, 通过Western blot检测实验组和对照组细胞ERK1/2通路及p38通路的激活状况。对SW480细胞进行信号通路抑制剂的预处理, 再予以低剂量FasL刺激, 采用Western blot、RT-PCR检测是否发生EMT过程, 从而探索Fas通路诱导EMT的可能机制。   结果   低剂量FasL可使结肠癌SW480和DLD1细胞的上皮标记物表达下调, 间质标记物表达上调, EMT相关转录因子在细胞核周聚集, 细胞发生梭形改变, 提示发生EMT。而将结肠癌细胞的Snail或Twist基因敲除后, FasL的上述诱导作用明显减弱。低剂量FasL可激活结肠癌细胞的ERK1/2通路激活, 而ERK抑制剂可减弱FasL诱导的EMT过程   结论   Fas通路可能通过激活ERK1/2通路诱导结肠癌细胞发生EMT。