Agrin-Lrp4 pathway in hippocampal astrocytes restrains development of temporal lobe epilepsy through adenosine signaling.

BACKGROUND: Human patients often experience an episode of serious seizure activity, such as status epilepticus (SE), prior to the onset of temporal lobe epilepsy (TLE), suggesting that SE can trigger the development of epilepsy. Yet, the underlying mechanisms are not fully understood. The low-density lipoprotein receptor related protein (Lrp4), a receptor for proteoglycan-agrin, has been indicated to modulate seizure susceptibility. However, whether agrin-Lrp4 pathway also plays a role in the development of SE-induced TLE is not clear. METHODS: Lrp4f/f mice were crossed with hGFAP-Cre and Nex-Cre mice to generate brain conditional Lrp4 knockout mice (hGFAP-Lrp4-/-) and pyramidal neuron specific knockout mice (Nex-Lrp4-/-). Lrp4 was specifically knocked down in hippocampal astrocytes by injecting AAV virus carrying hGFAP-Cre into the hippocampus. The effects of agrin-Lrp4 pathway on the development of SE-induced TLE were evaluated on the chronic seizure model generated by injecting kainic acid (KA) into the amygdala. The spontaneous recurrent seizures (SRS) in mice were video monitored. RESULTS: We found that Lrp4 deletion from the brain but not from the pyramidal neurons elevated the seizure threshold and reduced SRS numbers, with no change in the stage or duration of SRS. More importantly, knockdown of Lrp4 in the hippocampal astrocytes after SE induction decreased SRS numbers. In accord, direct injection of agrin into the lateral ventricle of control mice but not mice with Lrp4 deletion in hippocampal astrocytes also increased the SRS numbers. These results indicate a promoting effect of agrin-Lrp4 signaling in hippocampal astrocytes on the development of SE-induced TLE. Last, we observed that knockdown of Lrp4 in hippocampal astrocytes increased the extracellular adenosine levels in the hippocampus 2 weeks after SE induction. Blockade of adenosine A1 receptor in the hippocampus by DPCPX after SE induction diminished the effects of Lrp4 on the development of SE-induced TLE. CONCLUSION: These results demonstrate a promoting role of agrin-Lrp4 signaling in hippocampal astrocytes in the development of SE-induced development of epilepsy through elevating adenosine levels. Targeting agrin-Lrp4 signaling may serve as a potential therapeutic intervention strategy to treat TLE.

Periostin drives extracellular matrix degradation, stemness, and chemoresistance by activating the MAPK/ERK signaling pathway in triple-negative breast cancer cells.

BACKGROUND: Adipose tissue, which is mainly composed of adipocytes, is a crucial component of the tumor microenvironment, particularly in breast cancer. Adipocytes surround breast cancer cells and may participate in cell‒cell interactions in the breast microenvironment. However, little is currently known about how adipocytes influence the biological behavior of the surrounding breast cancer cells. Hence, this study sought to investigate the role and underlying mechanisms of periostin in triple-negative breast cancer (TNBC) cells cocultured with adipogenic conditioned medium (ACM) and palmitic acid (PA). METHODS: Human TNBC cell lines (MDA‒MB‒231 and SUM159PT) were treated with ACM and PA, then the expression of periostin, matrix metalloproteinases (MMPs) and stemness-related molecules were assessed by Western blotting and RT‒qPCR. The cellular viability was assessed using CCK‒8 assay. Plasmid transfection, RNA sequencing, and pathway inhibitor were used to explore the specific mechanisms of periostin. RESULTS: ACM and PA elevated the expression of both MMPs and stemness-related molecules in TNBCs. MMPs can promote tumor cell infiltration and migration by degrading the extracellular matrix, and stemness expression increases the development of tumor chemoresistance. Additionally, ACM and PA increased periostin expression, while inhibiting periostin disrupted the involvement of ACM and PA in promoting extracellular matrix degradation, stemness, and chemoresistance in TNBCs. Furthermore, this study found that periostin promoted TNBC progression by activating the MAPK/ERK signaling pathway and that inhibition of MAPK/ERK signaling reduced the phenotype caused by periostin upregulation in TNBCs treated with ACM or PA. Finally, the present results showed that the high expression of POSTN, which encodes periostin, was substantially related to worse survival in TNBC patients. CONCLUSIONS: The results of the study elucidated for the first time how periostin is the key protein secreted in TNBCs in response to the adipocyte-regulated tumor microenvironment, while periostin-neutralizing antibodies may serve as potential therapeutic agents in relation to TNBC progression.

FOXQ1 inhibits breast cancer ferroptosis and progression via the circ_0000643/miR-153/SLC7A11 axis.

Dysregulation of ferroptosis is involved in breast cancer progression and therapeutic responses. Inducing ferroptosis can be a potential therapeutic strategy for breast cancer treatment. Forkhead box Q1 (FOXQ1) is an oncogenic transcription factor that highly expressed and related with poor outcomes in various tumors. However, the specific effects of FOXQ1 on ferroptosis in breast cancer is unclear. In this study, we intended to explore the functions and potential mechanisms of FOXQ1 in breast cancer ferroptosis. By CCK-8, colony formation, wound healing, transwell and ferroptosis related assays, we explored the functions of FOXQ1 in breast cancer ferroptosis and progression. Through bioinformatics analysis of public database, luciferase reporter assay, RIP and ChIP assay, we investigated the potential mechanisms of FOXQ1 in breast cancer ferroptosis and progression. We found that FOXQ1 was overexpressed in breast cancer and associated with worse survival. Additionally, inhibition of FOXQ1 suppressed breast cancer ferroptosis and progression. Mechanically, we confirmed that FOXQ1 could bind to the promoter of circ_0000643 host gene to increase the levels of circ_0000643, which could sponge miR-153 and enhance the expression of SLC7A11, leading to reduced cell ferroptosis in breast cancer cells. Targeting the FOXQ1/circ_0000643/miR-153/SLC7A11 axis could be a promising strategy in breast cancer treatment.

IFT20 Confers Paclitaxel Resistance by Triggering ß-arrestin-1 to Modulate ASK1 Signaling in Breast Cancer.

ABSTRACT: System paclitaxel-based chemotherapy is the first-line treatment regimen of defense against breast cancer, but inherent or acquired chemotherapy resistance remains a major obstacle in breast cancer therapy. Elucidating the molecular mechanism of chemoresistance is essential to improve the outcome of patients with breast cancer. Here, we demonstrate that intraflagellar transport 20 (IFT20) is positively associated with shorter relapse-free survival in patients with system paclitaxel-based chemotherapy. High-expressed IFT20 in breast cancer cells increases resistance to cell death upon paclitaxel treatment; in contrast, IFT20 knockdown enhances apoptosis in breast cancer cells in response to paclitaxel. Mechanistically, IFT20 triggers ß-arrestin-1 to bind with apoptosis signal-regulating kinase 1 (ASK1) and promotes the ubiquitination of ASK1 degradation, leading to attenuating ASK1 signaling and its downstream JNK cascades, which helps cells to escape from cell death during paclitaxel treatment. Our results reveal that IFT20 drives paclitaxel resistance through modulating ASK1 signaling and identifies IFT20 as a potential molecular biomarker for predicting the response to paclitaxel therapeutic in breast cancer. IMPLICATIONS: IFT20 drives paclitaxel resistance through modulating ASK1 signaling and IFT20 may act as a potential molecular biomarker for predicting the response to paclitaxel therapeutic in breast cancer.

Smoke-induced SAV1 Gene Promoter Hypermethylation Disrupts YAP Negative Feedback and Promotes Malignant Progression of Non-small Cell Lung Cancer.

YAP (gene symbol YAP1) as a potential oncoprotein, is positively correlated with the malignancy of various tumors. However, overexpression of YAP alone in multiple normal tissue cells has failed to induce tumor formation and the underlying mechanism is poorly understood. Herein, we show that YAP activation directly induces transcription of its negative regulator, SAV1, to constitute a negative feedback loop, which plays a vital role in maintaining lung epithelial cell homeostasis and was dysregulated in non-small cell lung cancer (NSCLC). Notably, smoking promotes the hypermethylation of the SAV1 promoter region, which disrupts YAP negative feedback by inactivating the Hippo pathway. Besides, exogenous overexpression of SAV1 can act as a traffic protein, activating the Hippo signaling and concurrently inhibiting the WNT pathway to decrease cancer cell growth. Furthermore, using the lung cancer organoids, we found that lentivirus-mediated SAV1 gene transfer combined with methylation inhibitor and YAP-TEAD inhibitor is a potential feasible clinical medication regimen for the lung cancer patient, especially among the smoking population. Thus, this SAV1 mediated feedback loop provides an efficient mechanism to establish the robustness and homeostasis of YAP regulation and as a potential target of gene therapy for the smoking NSCLC population.

Mechanisms of catapol inhibiting differentiation and glycolysis of Thl7 cells through MiR-143-3p / 中国药理学通报

Aim To investigate the mechanism of eata- pol (CAT) inhibiting differentiation and glyeolysis of Thl7 eel Is through miR-143-3p.Method The peripheral hloorl CD4 ∗ T eells of HA patients were obtained to deteet the expression of miR-143-3p and the mRNA levels of key glycolytic enzymes, ineluding glucose transporter 1 ( Glutl ) , hexokinase 2 ( HK2 ) , pyruvate kinase 2 (PKM2) , laetate dehydrogenase A ( LDHA).The differentiation of Thl7 eells was induced in vitro, and the ShRNA/lentivirus was applied to achieve the overexpression or knockdown of miR- 143-3 p.Un-transfected eells were divided into control group and CAT group (20, 40, 80 mg • L 1 ) , and transfected eells were divided into four groups: negative control group, miR-143-3p inhibitor group, miR- 143-3p mimies group, miR-143-3p inhibitor + CAT group.The percentage of Thl7 eells was deteeted by flow cytometry, and the level of IL-17A was detected by EL1SA.Quantitative real-time PCR was used to detect the mRNA expression of miR-143-3p and key glycolytic enzymes, and the levels of pyruvate and lactate were also detected.Results The mRNA expression of miR-143-3p in RA peripheral blood CD4 ∗ T cells was negatively correlated with disease severity ( DAS28 ) , transcription factor ROR-yt, and the key glycolytic enzymes Glutl/HK2/LDHA.Compared with negative control group, the down-expression of miR-143-3p markedly elevated the mRNA expression of ROR-yt, Glutl, HK2, LDHA, and the levels of IL-17A, pyruvate, lactate.Catalpol groups significantly up-regula- ted the expression of miR-143-3p, decreased the mRNA expression of HK2/LDHA and the levels of pvru- vate/lactate, and inhibited Thl7 cells differentiation.Compared with miR - 1 4 3 - 3 p inhibitor group , catapol could significantly inhibit the abnormal up-regulated of HK2/LDHA mRNA relative expression, pyruvate/lactate levels and the abnormal differentiation of Thl7 eells.Conclusion MiR-143-3p inhibits the differentiation and glycolysis of Thl7 cells.Catalpol could sup-press the glycolysis and differentiation of Thl7 eells by regulating mill-143-3p.

Disruption of FOXO3a-miRNA feedback inhibition of IGF2/IGF-1R/IRS1 signaling confers Herceptin resistance in HER2-positive breast cancer.

Resistance to Herceptin represents a significant challenge for successful treatment of HER2-positive breast cancer. Here, we show that in Herceptin-sensitive cells, FOXO3a regulates specific miRNAs to control IGF2 and IRS1 expression, retaining basic IGF2/IGF-1R/IRS1 signaling. The basic activity maintains expression of PPP3CB, a subunit of the serine/threonine-protein phosphatase 2B, to restrict FOXO3a phosphorylation (p-FOXO3a), inducing IGF2- and IRS1-targeting miRNAs. However, in Herceptin-resistant cells, p-FOXO3a levels are elevated due to transcriptional suppression of PPP3CB, disrupting the negative feedback inhibition loop formed by FOXO3a and the miRNAs, thereby upregulating IGF2 and IRS1. Moreover, we detect significantly increased IGF2 in blood and IRS1 in the tumors of breast cancer patients with poor response to Herceptin-containing regimens. Collectively, we demonstrate that the IGF2/IGF-1R/IRS1 signaling is aberrantly activated in Herceptin-resistant breast cancer via disruption of the FOXO3a-miRNA negative feedback inhibition. Such insights provide avenues to identify predictive biomarkers and effective strategies overcoming Herceptin resistance.

Long Noncoding RNA Expression Profiles of Periodontal Ligament Stem Cells from the Periodontitis Microenvironment in Response to Static Mechanical Strain.

During the period of orthodontic tooth movement, periodontal ligament stem cells (PDLSCs) play an important role in transducing mechanical stimulation and tissue remodeling. However, our previous studies verified that the periodontitis microenvironment causes damage to the biological functions of PDLSCs and abnormal mechanical sensitivity. Long noncoding RNAs (lncRNAs) participate in the inflammatory pathogenesis and development of many diseases. Whether lncRNAs are abnormally expressed in PDLSCs obtained from periodontal tissues of periodontitis patients (PPDLSCs) and whether putative lncRNAs participate in the mechanotransductive process in PDLSCs remain poorly understood. First, we subjected PDLSCs obtained from healthy periodontal tissues (HPDLSCs) and PPDLSCs to static mechanical strain (SMS) with 12% elongation at 0.1 Hz frequency using an FX-4000T system and screened overall lncRNA profiles in both cell types by microarray. Among lncRNAs with a fold change (FC) > 20.0, 27 lncRNAs were upregulated in strained HPDLSCs, and 16 lncRNAs (9 upregulated and 7 downregulated) were detected in strained PPDLSCs. For mRNAs with FC > 20.0, we detected 25 upregulated mRNAs and one downregulated mRNA in strained HPDLSCs and 7 upregulated and 5 downregulated mRNAs in strained PPDLSCs. Further enrichment analysis showed that, unlike HPDLSCs with annotations principally involving transduction-associated signaling pathways, dysregulated mRNAs in PPDLSCs are mainly responsible for pathological conditions. Moreover, coexpressed lncRNA-mRNA networks confirmed the pathological state and exacerbated inflammatory conditions in strained PPDLSCs. Taken together, when compared with strained HPDLSCs, various lncRNAs and mRNAs were dysregulated in PPDLSCs under mechanical forces, implicating the response of lncRNAs in PPDLSCs to mechanical stress. Moreover, we provide potential lncRNA targets, which may contribute to future intervention strategies for orthodontic treatment in periodontitis patients.

Association between the genetic polymorphisms of the pharmacokinetics of anthracycline drug and myelosuppression in a patient with breast cancer with anthracycline-based chemotherapy.

AIMS: Exploring the genetic polymorphisms involved in the metabolism of anthracyclines can explain the causes of individual differences in myelosuppression during anthracycline-based chemotherapy. MAIN METHODS: By PCR and Sanger sequencing, SNP of candidate genes participating into the pharmacokinetics of anthracycline, including chemotherapeutic drug intake (SLC22A16 rs6907567), metabolism (AKR1A1 rs2088102, CBR1 rs20572) and transfer (ABCG2 rs2231142) are detected in 194 breast cancer patients undergoing anthracycline-based postoperative adjuvant chemotherapy. KEY FINDINGS: The CBR1 rs20572 (C>T) polymorphic allele, the ABCG2 rs2231142 (G>T) polymorphic allele, or the two polymorphic allele in combination significantly reduced the risk of leukopenia (OR 0.412, 95% CI 0.187-0.905, p = 0.025) and neutropenia (OR 0.354, 95% CI 0.148-0.846, p = 0.018). Either polymorphic allele T of CBR1 rs20572, or polymorphic allele C of AKR1A1 rs2088102 combined with the presence of both ABCG2 rs2231142(G>T) and SLC22A16 rs6907567(A>G) mutations were at extremely low risk of severe anemia of grades 3 and 4 (OR 0.058, 95% CI 0.006-0.554, p = 0.008, OR 0.065, 95% CI 0.006-0.689, p = 0.022, OR 0.037, 95% CI 0.004-0.36, p = 0.015, respectively). SIGNIFICANCE: These results suggested CBR1 rs20572, ABCG2 rs2231142, SLC22A16 rs6907567 and AKR1A1 rs2088102 might be potential protective factors for the reduction of hematologic toxicity incidence during anthracycline-based chemotherapy in breast cancer patients.

FOXO3a-driven miRNA signatures suppresses VEGF-A/NRP1 signaling and breast cancer metastasis.

Metastasis remains the major obstacle to improved survival for breast cancer patients. Downregulation of FOXO3a transcription factor in breast cancer is causally associated with the development of metastasis through poorly understood mechanisms. Here, we report that FOXO3a is functionally related to the inhibition of VEGF-A/NRP1 signaling and to the consequent suppression of breast cancer metastasis. We show that FOXO3a directly induces miR-29b-2 and miR-338 expression. Ectopic expression of miR-29b-2/miR-338 significantly suppresses EMT, migration/invasion, and in vivo metastasis of breast cancer. Moreover, we demonstrate that miR-29b-2 directly targets VEGF-A while miR-338 directly targets NRP1, and show that regulation of miR-29b-2 and miR-338 mediates the ability of FOXO3a to suppress VEGF-A/NRP1 signaling and breast cancer metastasis. Clinically, our results show that the FOXO3a-miR-29b-2/miR-338-VEGF-A/NRP1 axis is dysregulated and plays a critical role in disease progression in breast cancer. Collectively, our findings propose that FOXO3a functions as a metastasis suppressor, and define a novel signaling axis of FOXO3a-miRNA-VEGF-A/NRP1 in breast cancer, which might be potential therapeutic targets for breast cancer.

Asymmetrical dimethylarginine induces dysfunction of insulin signal transduction via endoplasmic reticulum stress in the liver of diabetic rats.

AIMS: Endoplasmic reticulum stress (ERS) as an emerging factor is involved in insulin resistance (IR), which is the pathological basis of diabetes mellitus. Accumulation of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase is associated with IR, but the underlying mechanisms have not been elucidated. This study was to reveal the important role of ADMA in IR and determine whether endogenous ADMA accumulation contributes to hepatic IR via ERS in diabetic rats and hepatocytes. MATERIALS AND METHODS: Diabetic rat model was induced by a single intraperitoneal injection of streptozotocin (50 mg/kg). Phosphorylation of insulin receptor substrate 1 (IRS1) and protein kinase B (Akt) was detected to evaluate IR. The protein kinase PKR-like ER kinase (PERK) and eukaryotic initiation factor 2α kinase (eIF2α) phosphorylation, x-box binding protein-1 (XBP-1) splicing, glucose-regulated protein 78 (GRP78) and C/EBP homologues protein (CHOP) expressions were measured to assess ERS. KEY FINDINGS: Endogenous ADMA content was significantly increased and positively correlated with either IR as evidenced by increased IRS1 at serine and reduced Akt phosphorylation or ERS as indicated by upregulations of PERK and eIF2α phosphorylation, XBP-1 splicing, GRP78 and CHOP expressions in the liver of diabetic rats compared with control rats. Exogenous ADMA directly caused IR and ERS in dose- and time-dependent manners in primary mouse hepatocytes. Pretreatment with ERS inhibitor 4-phenylbutyrate or ADMA antagonist L-arginine not only improved ADMA-associated or -induced hepatic IR but also attenuated ADMA-associated or -induced ERS in diabetic rats or hepatocytes. SIGNIFICANCE: These findings indicate that endogenous ADMA accumulation contributes to hepatic IR via ERS in diabetic rats.

Quantitative multiplex immunofluorescence analysis identifies infiltrating PD1+ CD8+ and CD8+ T cells as predictive of response to neoadjuvant chemotherapy in breast cancer.

BACKGROUND: This study aimed to explore the potentially predictive role and dynamic changes of immune checkpoints on T cell subsets in patients with breast cancer receiving neoadjuvant chemotherapies. METHODS: Fluorescent multiplex immunohistochemistry (mIHC) was used to stain CD4, CD8, PD1, TIM3, and cytokeratins simultaneously in paired breast cancer samples before and after neoadjuvant therapies (NAT) in a prospective cohort (n = 50). Singleplex IHC was conducted to stain for CD3 in 100 cases with inclusion of extra retrospective 50 cases. Cell levels were correlated with clinicopathological parameters and pathological complete response (pCR). RESULTS: In pretreatment tumors, the percentages of infiltrating CD8+ , PD1+ , PD1+ CD8+ , and the ratio of PD1+ CD8+ /CD8+ cells, were higher in pCR than non-pCR patients in either the stromal or intratumoral area, but PD1+ CD4+ , TIM3+ CD4+ , TIM3+ CD8+ cells and CD4+ /CD8+ ratio was not. Multivariate analyses showed that the percentage of intratumoral CD8+ cells (OR, 1.712; 95% CI: 1.052-2.786; P = 0.030) and stromal PD1+ CD8+ /CD8+ ratio (OR, 1.109; 95% CI: 1.009-1.218; P = 0.032) were significantly associated with pCR. Dynamically, reduction in the percentages of PD1+ , CD8+ and PD1+ CD8+ cells after therapy strongly correlated with pCR. Notably, incremental percentages of PD1+ CD8+ cells, rather than TIM3+ CD8+ , were shown in tumors from non-pCR patients after NAT. CD3 staining confirmed the percentage of T cells were associated with pCR. CONCLUSIONS: PD1+ CD8+ rather than TIM3+ CD8+ cells are main predictive components within tumor-infiltrating T cells in NAT breast cancer patients. Dynamically incremental levels of PD1+ CD8+ cells occurred in non-pCR cases after NAT, suggesting the combination of chemotherapy with PD1 inhibition might benefit these patients. KEY POINTS: SIGNIFICANT FINDINGS OF THE STUDY: PD1+ CD8+ , rather than TIM3+ CD8+ , T cells are the main component to predict the response of neoadjuvant therapies in breast cancer. WHAT THIS STUDY ADDS: Incremental levels of PD1+ CD8+ T cells in non-pCR post-NAT tumors suggest PD1 inhibition might benefit in the neoadjuvant setting.

[Research Advance on the Role of Spleen Tyrosine Kinase Inhibitors in Hematologic Malignancies].

Abstract　　Spleen tyrosine kinase (SYK) is not only a key kinase in the B-cell receptor (BCR) signaling pathway, but also a critical component of other signal transduction pathways such as Fc receptor, complement receptor and integrin. Abnormal activation of SYK closely related to the occurrence and development of hematological malignancies, thus targeting SYK has become a research hotspot. Several SYK inhibitors including Fostamatinib, Entospletinib and Cerdulatinib were being evaluated in clincal trials. As a second generation SYK inhibitor, Entospletinib has achieved good efficacy in lymphoid and myeloid hematologic tumors. Furthermore, Entospletinib can significantly relieve hematopoietic stem cell transplantation(HCT) related graft versus host disease (GVHD). In this review the role of SYK inhibitors in treatment of hematological malignancies is summarized brifely.

[Reaserch Advance on Inhibitor Targeting at the B-Cell Receptor Pathway in Chronic Lymphocytic Leukemia --Review].

Abstract　　Disregulated BCR signaling pathway plays an important role in the occurence and progress of chronic lymphocytic leukemia (CLL). As key kinases of BCR pathway, the Bruton tyrosine kinase (BTK), phosphoinositide 3-kinase (PI3K) and spleen tyrosine kinase (SYK) have become the focus of CLL targeted therapy. Over the past decade, drugs targeting of BCR pathway for CLL treatment have been continuously developed, including BTK inhibitors, PI3K inhibitors and SYK inhibitors. To date, the BTK inhibitor Ibrutinib, PI3K inhibitors Idelalisib and Duvelisib have been approved for CLL treatment, and some novel inhibitors are still in clinical trials. These targeted drugs are much less toxic than chemoimmunotherapy and show better efficacy in certain high-risk patients such as del 17P. These inhibitors targeted BCR pathway are increasingly prominent in CLL treatment and gradually replace traditional chemoimmunotherapy.

SRGN crosstalks with YAP to maintain chemoresistance and stemness in breast cancer cells by modulating HDAC2 expression.

Background: Chemoresistance is a significant obstacle to the effective treatment of breast cancer (BC), resulting in more aggressive behavior and worse clinical outcome. The molecular mechanisms underlying breast cancer chemoresistance remain unclear. Our microarray analysis had identified the overexpression of a small molecular glycoprotein serglycin (SRGN) in multidrug-resistant BC cells. Here, we aimed to investigate the role of SRGN in chemoresistance of breast cancer and elucidate the underlying mechanisms. Methods: SRNG overexpression was identified using microarray analysis and its clinical relevance was analyzed. To investigate the role of SRGN, we performed various in vitro and in vivo studies, as well as characterization of serum and tissue samples from BC patients. Chemosensitivity measurement, gene expression interference, immunofluorescence staining, mammosphere assay, flow cytometry analysis, luciferase reporter assay, ChIP-qPCR, coimmunoprecipitation, and immunohistochemistry were performed to explore the potential functions and mechanisms of SRGN. Results: We confirmed overexpression of SRGN in chemoresistant BC cells and in serum and tissue samples from BC patients with poor response to chemotherapy. SRGN specifically predicted poor prognosis in BC patients receiving chemotherapy. Mechanistically, SRGN promoted chemoresistance both in vitro and in vivo by cross-talking with the transcriptional coactivator YES-associated protein (YAP) to maintain stemness in BC cells. Ectopic YAP expression restored the effects of SRGN knockdown. Inversely, YAP knockdown rescued the effects of SRGN overexpression. The secreted SRGN triggered ITGA5/FAK/CREB signaling to enhance YAP transcription. Reciprocally, YAP promoted SRGN transcription in a TEAD1-dependent manner to form a feed-forward circuit. Moreover, the YAP/RUNX1 complex promoted HDAC2 transcription to induce chemoresistance and stemness in BC cells. Importantly, the SRGN levels were positively correlated with the YAP and HDAC2 levels in chemoresistant BC tissues. YAP and HDAC2 acted downstream of SRNG and correlated with poor outcomes of BC patients receiving chemotherapy. Conclusions: Our findings clarify the roles and mechanisms of SRGN in mediating chemoresistance in breast cancer and suggest its use a potential biomarker for chemotherapeutic response. We believe that novel therapeutic strategies for breast cancer can be designed by targeting the signaling mediated by the crosstalk between SRGN and YAP.

[Reaserch Advance on Bruton Tyrosine Kinase Inhibitors in the Treatment of B-Cell Tumors--Review].

Abstract　　In recent years, development of the targeted drugs according to the biological characteristics of tumors have provided more treatment options for tumor patients. It was found that the overactivation or abnormality of B cell receptor (BCR) signal pathway closely related to the occurrence and development of various B cell tumors, such as chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL). As a key kinase in the BCR pathway, BTK inhibitors have obvious anti-tumor effect when its activity is being inhibitered. Currently, BTK inhibitors developed include the first-generation Ibrutinib and the second-generation Acalabrutinib, which can be targeted at the inhibition of BTK and its downstream signaling pathway, and have important therapeutic value for a variety of B-cell tumors, such as CLL and partial non-Hodgkin's lymphoma (NHL). However, its side effects and drug-resistance also gradually emerged, effective drug combination therapy has shown a certain clinical activity. This reviews summarizes briefly the mechanism and status of BTK inhibitors in the treatment of various B-cell tumors.

Research Advance on the Role of Spleen Tyrosine Kinase Inhibitors in Hematologic Malignancies / 中国实验血液学杂志

Abstract　　Spleen tyrosine kinase (SYK) is not only a key kinase in the B-cell receptor (BCR) signaling pathway, but also a critical component of other signal transduction pathways such as Fc receptor, complement receptor and integrin. Abnormal activation of SYK closely related to the occurrence and development of hematological malignancies, thus targeting SYK has become a research hotspot. Several SYK inhibitors including Fostamatinib, Entospletinib and Cerdulatinib were being evaluated in clincal trials. As a second generation SYK inhibitor, Entospletinib has achieved good efficacy in lymphoid and myeloid hematologic tumors. Furthermore, Entospletinib can significantly relieve hematopoietic stem cell transplantation(HCT) related graft versus host disease (GVHD). In this review the role of SYK inhibitors in treatment of hematological malignancies is summarized brifely.

Reaserch Advance on Bruton Tyrosine Kinase Inhibitors in the Treatment of B-Cell Tumors--Review / 中国实验血液学杂志

Abstract　　In recent years, development of the targeted drugs according to the biological characteristics of tumors have provided more treatment options for tumor patients. It was found that the overactivation or abnormality of B cell receptor (BCR) signal pathway closely related to the occurrence and development of various B cell tumors, such as chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL). As a key kinase in the BCR pathway, BTK inhibitors have obvious anti-tumor effect when its activity is being inhibitered. Currently, BTK inhibitors developed include the first-generation Ibrutinib and the second-generation Acalabrutinib, which can be targeted at the inhibition of BTK and its downstream signaling pathway, and have important therapeutic value for a variety of B-cell tumors, such as CLL and partial non-Hodgkin's lymphoma (NHL). However, its side effects and drug-resistance also gradually emerged, effective drug combination therapy has shown a certain clinical activity. This reviews summarizes briefly the mechanism and status of BTK inhibitors in the treatment of various B-cell tumors.

[Research Progress of m6A-Methylation in Acute Leukemia-Review].

OBJECTIVE: Epigenetic abnormalities play an important role in the pathogenesis of hematological malignancies, especially acute leukemia (AL). Similar to DNA methylation and histone modifications, RNA methylation is another important epigenetic modification. m6A methylation is one of the most prevalent and extensively studied RNA methylation. m6A methylation is involved in many biological and pathological process. Recent studies have found that m6A methylation is involved in the occurrence, development and drug-resistance of AL. This review focuses on the research progress of m6A methylation in AL.

Cullin7 enhances resistance to trastuzumab therapy in Her2 positive breast cancer via degrading IRS-1 and downregulating IGFBP-3 to activate the PI3K/AKT pathway.

Patients with Her2-positive breast cancer exhibit de novo resistance or develop acquired resistance in less than one year after Her2 targeting treatment, but the mechanism is not fully elucidated. Compensatory pathways such as the IGF-1R/IRS-1 pathway, are activated, leading to aberrant enhanced PI3K/Akt/mTOR pathway activity to attenuate the efficacy of trastuzumab. Cullin7 could participate in the degradation of IRS-1 in a mTOR/S6K dependent manner. Whether Cullin7 participates in trastuzumab resistance needs to be further investigated. Here, we reveals that Cullin7 is overexpressed in trastuzumab-resistant Her2 positive breast cancer cells. Knockdown of Cullin7 reduces degradation of Ser phosphorylation of IRS-1, attenuates activation of the PI3K/AKT pathway, and partly restores trastuzumab sensitivity in trastuzumab-resistant Her2 positive breast cancer cells. IGFBP-3 expression is decreased in trastuzumab-resistant Her2 positive breast cancer cells, which leads to release of the Wnt signaling pathway inhibition and an increase in Cullin7 expression, as mediated by TCF7L2. Overexpression of Cullin7 in Her2-amplified breast cancer tissues has clinical implications because it positively correlates with shorter disease-free survival (DFS) and inadequate response to trastuzumab. Thus, our results suggest a critical role for Cullin7 in response to trastuzumab, which has significant implications for selection of the optimal therapeutic strategy for Her2 positive breast cancers.