Mechanism of ELL-associated factor 2 and vasohibin 1 regulating invasion,migration,and angiogenesis in colorectal cancer

BACKGROUND As a novel endogenous anti-angiogenic molecule, vasohibin 1(VASH1) is not only expressed in tumor stroma, but also in tumor tissue. Moreover, studies have shown that VASH1 may be a prognostic marker in colorectal cancer(CRC). Knockdown of VASH1 enhanced transforming growth factor-β1(TGF-β1)/Smad3 pathway activity and type Ⅰ/Ⅲ collagen production. Our previous findings suggest that ELL-associated factor 2(EAF2) may play a tumor suppressor and protective role in the development and progression of CRC by regulating signal transducer and activator of transcription 3(STAT3)/TGF-β1 signaling pathway. However, the functional role and mechanism of VASH1-mediated TGF-β1 related pathway in CRC has not been elucidated.AIM To investigate the expression of VASH1 in CRC and its correlation with the expression of EAF2. Furthermore, we studied the functional role and mechanism of VASH1 involved in the regulation and protection of EAF2 in CRC cells in vitro.METHODS We collected colorectal adenocarcinoma and corresponding adjacent tissues to investigate the clinical expression of EAF2 protein and VASH1 protein in patients with advanced CRC. Following, we investigated the effect and mechanism of EAF2 and VASH1 on the invasion, migration and angiogenesis of CRC cells in vitro using plasmid transfection.RESULTS Our findings indicated that EAF2 was down-regulated and VASH1 was upregulated in advanced CRC tissue compared to normal colorectal tissue. KaplanMeier survival analysis showed that the higher EAF2 Level group and the lower VASH1 Level group had a higher survival rate. Overexpression of EAF2 might inhibit the activity of STAT3/TGF-β1 pathway by up-regulating the expression of VASH1, and then weaken the invasion, migration and angiogenesis of CRC cells.CONCLUSION This study suggests that EAF2 and VASH1 may serve as new diagnostic and prognostic markers for CRC, and provide a clinical basis for exploring new biomarkers for CRC. This study complements the mechanism of EAF2 in CRC cells, enriches the role and mechanism of CRC cellderived VASH1, and provides a new possible subtype of CRC as a therapeutic target of STAT3/TGF-β1 pathway.

The gene expression patterns of BMPR2,EP300,TGFβ2,and TNFAIP3 in B-Lymphoma cells

Objective: The results of a previous study showed that a clear dysregulation was evident in the global gene expression of the BCL11A-suppressed B-lymphoma cells. In this study, the bone morphogenetic protein receptor, type II(BMPR2), E1 A binding protein p300(EP300), transforming growth factor-β2(TGFβ2), and tumor necrosis factor, and alpha-induced protein 3(TNFAIP3) gene expression patterns in B-cell malignancies were studied. Methods: The relative expression levels of BMPR2, EP300, TGFβ2, and TNFAIP3 mRNA in B-lymphoma cell lines, myeloid cell lines, as well as in cells from healthy volunteers, were determined by real-time quantitative reverse transcriptpolymerase chain reaction(qRT-PCR) with SYBR Green Dye. Glyceraldehyde-3-phosphate dehydrogenase(GAPDH) was used as reference. Results: The expression level of TGFβ2 mRNA in B-lymphoma cell lines was significantly higher than those in the cells from the healthy control(P<0.05). However, the expression level of TNFAIP3 mRNA in B-malignant cells was significantly lower than that of the healthy control(P<0.05). The expression levels of BMPR2 and EP300 mRNA showed no significant difference between B-malignant cell lines and the healthy group(P>0.05). In B-lymphoma cell lines, correlation analyses revealed that the expression of BMPR2 and TNFAIP3(r=0.882, P=0.04) had significant positive relation. The expression levels of BMPR2, EP300, and TNFAIP3 mRNA in cell lines from myeloid leukemia were significantly lower than those in the cells from the healthy control(P<0.05). The expression levels of TGFβ2 mRNA showed no significant difference between myeloid leukemia cell lines and the healthy control or B-malignant cell lines(P>0.05). The expression levels of BMPR2, EP300, and TNFAIP3 mRNA in B-lymphoma cells were significantly higher than those of the myeloid leukemia cells(P<0.05).Conclusion: Different expression patterns of BMPR2, EP300, TGFβ2, and TNFAIP3 genes in B-lymphoma cells exist.

Overexpression of ELL-associated factor 2 suppresses invasion,migration,and angiogenesis in colorectal cancer

BACKGROUND The androgen responsive gene,ELL-associated factor 2(EAF2),expressed in benign prostate tissues,has been shown to play an important role in tumor suppression in a variety of malignant tumors.In addition,some scholars found that EAF2 frameshift mutations are associated with intratumor heterogeneity in colorectal cancer(CRC)and inactivation of EAF2 in microsatellite instability-high CRC.However,the molecular mechanism by which EAF2 is involved in CRC invasion and metastasis remains unclear.AIM To determine the clinical value of expression of EAF2 protein in CRC,and to study the effects of EAF2 on the invasion,migration,and angiogenesis of CRC cells in vitro.METHODS In this study,we collected colorectal adenocarcinoma and corresponding adjacent tissues to investigate the clinical expression of EAF2 protein in patients with advanced CRC.Subsequently,we investigated the effect of EAF2 on the invasion,migration,and angiogenesis of CRC cells in vitro using plasmid transfection.RESULTS EAF2 protein was lowly expressed in cancer tissues of patients with advanced CRC.Kaplan-Meier survival analysis showed that the survival rate of the high EAF2 level group was higher than that of the low EAF2 level group.CONCLUSION Our results demonstrated that EAF2,as a tumor suppressor,may inhibit the invasion,metastasis,and angiogenesis of CRC cells by regulating the signal transducer and activator of transcription 3/transforming growth factor-β1 crosstalk pathway,and play a cancer suppressive and protective role in the occurrence and development of CRC.Our findings are of great significance to provide a new idea and theoretical basis for the targeted diagnosis and treatment of CRC.

Therapeutic Effect and Mechanism of New Maixian Powder on DSS-induced UC Rats

[Objectives] To study the therapeutic effect and mechanism of New Maixian Powder on ulcerative colitis( UC) rats through observing its regulatory effect on the protein kinase R-like endoplasmic reticulum kinase( PERK)/eukaryotic translation initiation factor-2α( e IF-2α)/nuclear transcription factor-kappa B( NF-κB) signaling pathway. [Methods]First,60 SD rats were randomly divided into normal group,model group,mesalazine group,and New Maixian Powder low,medium and high dose groups,10 rats each group. Then,dextran sulfate sodium( DSS) was used to induce UC rats. The mesalazine group was given 0. 42 g/( kg·d) of mesalazine sustained-release granule suspension,New Maixian Powder low,medium and high dose groups were given 1. 5,3,and 6 g/( kg·d) of New Maixian Powder suspension,respectively,and other groups were given an equal volume of physiological saline,continuous intragastric administration for 14 d. Next,the disease activity index( DAI) of UC rats was evaluated; the expression of NF-κB in serum was measured by enzyme-linked immunosorbent assay( ELISA); the expression of PERK and e IF-2α protein and m RNA in colon tissue was detected by Western blot and real-time quantitative polymerase chain reaction( RT q-PCR). [Results] Compared with the normal group,the DAI score and serum NF-κB level in the model group were significantly higher( P < 0. 05),and PERK and e IF-2α protein and m RNA levels in the colon tissue were increased( P < 0. 05); compared with the model group,the DAI score decreased and serum NF-κB level declined in the New Maixian Powder group,and the expression of PERK and e IF-2α protein and m RNA in New Maixian Powder medium dose and high dose groups declined( P < 0. 05). [Conclusions]New Maixian Powder has good therapeutic effect on UC rats,and its mechanism may be connected with the inhibition of the activation of PERK/e IF-2α/NF-κB signaling pathway.

S100A8 promotes epithelial-mesenchymal transition and metastasis under TGF-β/USF2 axis in colorectal cancer

Background:The transforming growth factor-β(TGF-β)pathway plays a pivotal role in inducing epithelial-mesenchymal transition(EMT),which is a key step in cancer invasion and metastasis.However,the regulatory mechanism of TGF-βin inducing EMT in colorectal cancer(CRC)has not been fully elucidated.In previous studies,it was found that S100A8 may regulate EMT.This study aimed to clarify the role of S100A8 in TGF-β-induced EMT and explore the underlying mechanism in CRC.Methods:S100A8 and upstream transcription factor 2(USF2)expression was detected by immunohistochemistry in 412 CRC tissues.Kaplan-Meier survival analysis was performed.In vitro,Western blot,and migration and invasion assays were performed to investigate the effects of S100A8 and USF2 on TGF-β-induced EMT.Mouse metastasis models were used to determine in vivo metastasis ability.Luciferase reporter and chromatin immunoprecipitation assay were used to explore the role of USF2 on S100A8 transcription.Results:During TGF-β-induced EMT in CRC cells,S100A8 and the transcription factor USF2 were upregulated.S100A8 promoted cell migration and invasion and EMT.USF2 transcriptionally regulated S100A8 expression by directly binding to its promoter region.Furthermore,TGF-βenhanced the USF2/S100A8 signaling axis of CRC cells whereas extracellular S100A8 inhibited the USF2/S100A8 axis of CRC cells.S100A8 expression in tumor cells was associated with poor overall survival in CRC.USF2 expression was positively related to S100A8 expression in tumor cells but negatively related to S100A8-positive stromal cells.Conclusions:TGF-βwas found to promote EMT and metastasis through the USF2/S100A8 axis in CRC while extracellular S100A8 suppressed the USF2/S100A8 axis.USF2 was identified as an important switch on the intracellular and extracellular S100A8 feedback loop.

Phospho-proteomics identifies a critical role of ATF2 in pseudorabies virus replication

Pseudorabies virus(PRV),an etiological agent of pseudorabies in livestock,has negatively affected the porcine industry all over the world.Epithelial cells are reported as the first site of PRV infection.However,the role of host proteins and its related signaling pathways in PRV replication is largely unclear.In this study,we performed a quantitative phosphoproteomics screening on PRV-infected porcine kidney(PK-15)epithelial cells.Totally 5723phosphopeptides,corresponding to 2180 proteins,were obtained,and the phosphorylated states of 810 proteins were significantly different in PRV-infected cells compared with mock-infected cells(P<0.05).GO and KEGG analysis revealed that these differentially expressed phosphorylated proteins were predominantly related to RNA transport and MAPK signaling pathways.Further functional studies of NF-κB,transcription activator factor-2(ATF2),MAX and SOS genes in MAPK signaling pathway were analyzed using RNA interference(RNAi)knockdown.It showed that only ATF2-knockdown reduces both PRV titer and viral genome copy number.JNK pathway inhibition and CRISPR/Cas9 gene knockout showed that ATF2 was required for the effective replication of PRV,especially during the biogenesis of viral genome DNA.Subsequently,by overexpression of the ATF2 gene and point mutation of the amino acid positions 69/71 of ATF2,it was further demonstrated that the phosphorylation of ATF2 promoted PRV replication.These findings suggest that ATF2 may provide potential therapeutic target for inhibiting PRV infection.

TGF-β1-regulated miR-3691-3p targets E2F3 and PRDM1 to inhibit prostate cancer progression

Transforming growth factor-β1(TGF-β1)acts as a tumor promoter in advanced prostate cancer(PCa).We speculated that microRNAs(miRNAs)that are inhibited by TGF-β1 might exert anti-tumor effects.To assess this,we identified several miRNAs downregulated by TGF-β1 in PCa cell lines and selected miR-3691-3p for detailed analysis as a candidate anti-oncogene miRNA.miR-3691-3p was expressed at significantly lower levels in human PCa tissue compared with paired benign prostatic hyperplasia tissue,and its expression level correlated inversely with aggressive clinical pathological features.Overexpression of miR-3691-3p in PCa cell lines inhibited proliferation,migration,and invasion,and promoted apoptosis.The miR-3691-3p target genes E2F transcription factor 3(E2F3)and PR domain containing 1,with ZNF domain(PRDM1)were upregulated in miR-3691-3p-overexpressing PCa cells,and silencing of E2F3 or PRDM1 suppressed PCa cell proliferation,migration,and invasion.Treatment of mice bearing PCa xenografts with a miR-3691-3p agomir inhibited tumor growth and promoted tumor cell apoptosis.Consistent with the negative regulation of E2F3 and PRDM1 by miR-3691-3p,both proteins were overexpressed in clinical PCa specimens compared with noncancerous prostate tissue.Our results indicate that TGF-β1-regulated miR-3691-3p acts as an anti-oncogene in PCa by downregulating E2F3 and PRDM1.These results provide novel insights into the mechanisms by which TGF-β1 contributes to the progression of PCa.

Emerging targets in cancer drug resistance

Drug resistance is a complex phenomenon that frequently develops as a failure to chemotherapy during cancer treatment.Malignant cells increasingly generate resistance to various chemotherapeutic drugs through distinct mechanisms and pathways.Understanding the molecular mechanisms involved in drug resistance remains an important area of research for identification of precise targets and drug discovery to improve therapeutic outcomes.This review highlights the role of some recent emerging targets and pathways which play critical role in driving drug resistance.