EPAC inhibitor suppresses angiogenesis and tumor growth of triple-negative breast cancer

AIMS

Exchange protein directly activated by cAMP 1 (EPAC1), a major isoform of guanine nucleotide exchange factors, is highly expressed in vascular endothelia cells and regulates angiogenesis in the retina. High intratumor microvascular densities (MVD) resulting from angiogenesis is responsible for breast cancer development. Downregulation of EPAC1 in tumor cell reduces triple-negative breast cancer (TNBC)-induced angiogenesis. However, whether Epac1 expressed in vascular endothelial cells contributes to angiogenesis and tumor development of TNBC remains elusive.

MAIN METHODS

We employed NY0123, a previously identified potent EPAC inhibitor, to explore the anti-angiogenic biological role of EPAC1 in vitro and in vivo through vascular endothelial cells, rat aortic ring, Matrigel plug, and chick embryo chorioallantoic membrane (CAM) and yolk sac membrane (YSM) assays, as well as the in vivo xenograft tumor models of TNBC in both chick embryo and mice.

KEY FINDINGS

Inhibiting EPAC1 in vascular endothelial cells by NY0123 significantly suppresses angiogenesis and tumor growth of TNBC. In addition, NY0123 possesses a better inhibitory efficacy than ESI-09, a reported specific EPAC inhibitor tool compound. Importantly, inhibiting EPAC1 in vascular endothelia cells regulates the typical angiogenic signaling network, which is associated with not only vascular endothelial growth factor (VEGF)/vascular endothelial growth factor receptor-2 (VEGFR2) signaling, but also PI3K/AKT, MEK/ERK and Notch pathway.

CONCLUSIONS

Our findings support that EPAC1 may serve as an effective anti-angiogenic therapeutic target of TNBC, and EPAC inhibitor NY0123 has the therapeutic potential to be developed for the treatment of TNBC.

CYD0281, a Bcl-2 BH4 domain antagonist, inhibits tumor angiogenesis and breast cancer tumor growth

BACKGROUND

B-cell lymphoma 2 (Bcl-2) family proteins are key regulators of apoptosis, which possess four conserved Bcl-2 homologies (BH) domains. Among the BH domains, the BH3 domain is considered as a potent 'death domain' while the BH4 domain is required for anti-apoptotic activity. Bcl-2 can be converted to a pro-apoptotic molecule through the removal or mutation of the BH4 domain. Bcl-2 is considered as an inducer of angiogenesis, which can promote tumor vascular network formation and further afford nutrients and oxygen to promote tumor progression. However, whether disrupting the function of the BH4 domain to convert Bcl-2 into a pro-apoptotic molecule could make Bcl-2 possess the potential for anti-angiogenic therapy remains to be defined.

METHODS

CYD0281 was designed and synthesized according to the lead structure of BDA-366, and its function on inducing a conformational change of Bcl-2 was further evaluated via immunoprecipitation (IP) and immunofluorescence (IF) assays. Moreover, the function of CYD0281 on apoptosis of endothelial cells was analyzed via cell viability, flow cytometry, and western blotting assays. Additionally, the role of CYD0281 on angiogenesis in vitro was determined via endothelial cell migration and tube formation assays and rat aortic ring assay. Chick embryo chorioallantoic membrane (CAM) and yolk sac membrane (YSM) models, breast cancer cell xenograft tumor on CAM and in mouse models as well as the Matrigel plug angiogenesis assay were used to explore the effects of CYD0281 on angiogenesis in vivo.

RESULTS

We identified a novel potent small-molecule Bcl-2-BH4 domain antagonist, CYD0281, which exhibited significant anti-angiogenic effects both in vitro and in vivo, and further inhibited breast cancer tumor growth. CYD0281 was found to induce conformational changes in Bcl-2 through the exposure of the BH3 domain and convert Bcl-2 from an anti-apoptotic molecule into a cell death inducer, thereby resulting in the apoptosis of vascular endothelial cells.

CONCLUSIONS

This study has revealed CYD0281 as a novel Bcl-2-BH4 antagonist that induces conformational changes of Bcl-2 to convert to a pro-apoptotic molecule. Our findings indicate that CYD0281 plays a crucial role in anti-angiogenesis and may be further developed as a potential anti-tumor drug candidate for breast cancer. This work also provides a potential anti-angiogenic strategy for breast cancer treatment.

NF-κB Activator 1 downregulation in macrophages activates STAT3 to promote adenoma-adenocarcinoma transition and immunosuppression in colorectal cancer

BACKGROUND

Adenoma-adenocarcinoma transition is a key feature of colorectal cancer (CRC) occurrence and is closely regulated by tumor-associated macrophages (TAMs) and CD8⁺ T cells. Here, we investigated the effect of the NF-κB activator 1 (Act1) downregulation of macrophages in the adenoma-adenocarcinoma transition.

METHODS

This study used spontaneous adenoma-developing Apc^Min/+, macrophage-specific Act1-knockdown (anti-Act1), and Apc^Min/+; anti-Act1 (AA) mice. Histological analysis was performed on CRC tissues of patients and mice. CRC patients' data retrieved from the TCGA dataset were analyzed. Primary cell isolation, co-culture system, RNA-seq, and fluorescence-activated cell sorting (FACS) were used.

RESULTS

By TCGA and TISIDB analysis, the downregulation of Act1 expression in tumor tissues of CRC patients negatively correlated with accumulated CD68⁺ macrophages in the tumor. Relative expression of EMT markers in the tumor enriched ACT1^lowCD68⁺ macrophages of CRC patients. AA mice showed adenoma-adenocarcinoma transition, TAMs recruitment, and CD8⁺ T cell infiltration in the tumor. Macrophages depletion in AA mice reversed adenocarcinoma, reduced tumor amounts, and suppressed CD8⁺ T cell infiltration. Besides, macrophage depletion or anti-CD8a effectively inhibited metastatic nodules in the lung metastasis mouse model of anti-Act1 mice. CRC cells induced activation of IL-6/STAT3 and IFN-γ/NF-κB signaling and the expressions of CXCL9/10, IL-6, and PD-L1 in anti-Act1 macrophages. Anti-Act1 macrophages facilitated epithelial-mesenchymal-transition and CRC cells' migration via CXCL9/10-CXCR3-axis. Furthermore, anti-Act1 macrophages promoted exhaustive PD1⁺ Tim3⁺ CD8⁺ T cell formation. Anti-PD-L1 treatment repressed adenoma-adenocarcinoma transition in AA mice. Silencing STAT3 in anti-Act1 macrophages reduced CXCL9/10 and PD-L1 expression and correspondingly inhibited epithelial-mesenchymal-transition and CRC cells' migration.

CONCLUSIONS

Act1 downregulation in macrophages activates STAT3 that promotes adenoma-adenocarcinoma transition via CXCL9/10-CXCR3-axis in CRC cells and PD-1/PD-L1-axis in CD8⁺ T cells.

Decylubiquinone Inhibits Colorectal Cancer Growth Through Upregulating Sirtuin2

Colorectal cancer (CRC) is one of the leading causes of cancer-related death worldwide. Decylubiquinone (DUb), a coenzyme Q10 analog, was reported to inhibit breast cancer growth and metastasis by us. However, the influence of DUb on CRC remains unclear. Herein, we found that DUb significantly inhibited CRC growth in the patient-derived xenograft (PDX) and CT26 xenograft models. DUb was further identified to significantly suppress CRC cell proliferation, colony formation, migration and invasion in a dose-dependent manner, while not inhibiting CRC cell apoptosis from flow cytometry assay. Sirtuin2 (SIRT2), a member of the sirtuin protein family, plays a critical role in growth and metastasis in various cancers. Moreover, DUb inhibited CRC progression by upregulating SIRT2. These findings reveal that DUb has the potential to a novel drug for the treatment of CRC by inhibiting CRC cell proliferation.

1H-NMR based metabolic study of MMTV-PyMT mice along with pathological progress to screen biomarkers for the early diagnosis of breast cancer

This study showed the common metabolic changes between BC patients and mice, which were related to pathological processes.

Testicular injury during SARS-CoV-2 infection may be neglected: An assessment from scRNA-seq profiling and protein detection of angiotensin-converting enzyme II

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), is outbreaking globally. SARS-CoV-2 invades host cells via angiotensin-converting enzyme II (ACE2) and causes multiple-organ injury. Autopsy studies indicated that the testis of patients with COVID-19 exhibited various degrees of spermatogenic cell reduction and injury, but the composition of ACE2-expressing cells and their proportion in the testes have remained to be determined. Recent clinical evidence suggested that the ratio of male sex hormones in males with COVID-19 was significantly changed. The present study aimed to explore whether SARS-CoV-2 is able to damage the male reproductive system. For this, the ACE2-expressing cell composition and proportion in male testes were analyzed using single-cell RNA sequencing (RNA-seq) datasets downloaded from the Gene Expression Omnibus (GEO) database and immunohistochemical (IHC) staining. The single-cell RNA-seq data indicated that ACE2 mRNA was highly expressed in myoid cells, Leydig cells and spermatogenic cells, accounting for 5.45, 1.24 and 0.423% of adult testicular cells. ACE2 mRNA-expressing Sertoli cells, spermatogenic cells and myoid cells accounted for 5.00, 0.56 and 0.73% of infant testicular cells. IHC demonstrated that ACE2 protein was also highly expressed in testicular tissues. In conclusion, the present results demonstrated that testicular injury may be missed by clinicians in patients with COVID-19 and male reproductive function should be closely followed up.

Glipizide Combined with ANP Suppresses Breast Cancer Growth and Metastasis by Inhibiting Angiogenesis through VEGF/VEGFR2 Signaling

BACKGROUND

Breast cancer is one of the most common cancers worldwide among women, and angiogenesis has an important effect on its growth and metastasis. Glipizide, which is a widely used drug for type 2 diabetes mellitus, has been reported to inhibit tumor growth and metastasis by upregulating the expression of natriuretic peptide receptor A (NPRA). Atrial natriuretic peptide (ANP), the receptor of NPRA, plays an important role in angiogenesis. The purpose of this study was to explore the effect of glipizide combined with ANP on breast cancer growth and metastasis.

METHODS

To investigate the effect of glipizide combined with ANP on breast cancer, glipizide, ANP or glipizide combined with ANP was intraperitoneally injected into MMTV-PyMT mice. To explore whether the anticancer efficacy of glipizide combined with ANP was correlated with angiogenesis, a tube formation assay was performed.

RESULTS

Glipizide combined with ANP was found to inhibit breast cancer growth and metastasis in MMTV-PyMT mice, which spontaneously develop breast cancer. Furthermore, the inhibitory effect of ANP combined with glipizide was better than that of glipizide alone. ANP combined with glipizide significantly inhibited tube formation of human umbilical vein endothelial cells (HUVECs) by suppressing vascular endothelial growth factor (VEGF)/VEGFR2 (vascular endothelial growth factor receptor 2) signaling.

CONCLUSIONS

These results demonstrate that glipizide combined with ANP has a greater potential than glipizide alone to be repurposed as effective agents for the treatment of breast cancer by targeting tumor-induced angiogenesis.

Andrographolide Suppresses the Growth and Metastasis of Luminal-Like Breast Cancer by Inhibiting the NF-κB/miR-21-5p/PDCD4 Signaling Pathway

Tumor growth and metastasis are responsible for breast cancer-related mortality. Andrographolide (Andro) is a traditional anti-inflammatory drug used in the clinic that inhibits NF-κB activation. Recently, Andro has been found in the treatment of various cancers. Andro inhibits breast cell proliferation and invasion and induces apoptosis via activating various signaling pathways. Therefore, the underlying mechanisms with regard to the antitumor effects of Andro still need to be further confirmed. Herein, a MMTV-PyMT spontaneous luminal-like breast cancer lung metastatic transgenic tumor model was employed to estimate the antitumor effects of Andro on breast cancer in vivo. Andro significantly inhibited tumor growth and metastasis in MMTV-PyMT mice and suppressed the cell proliferation, migration, and invasion of MCF-7 breast cancer cells in vitro. Meanwhile, Andro significantly inhibited the expression of NF-κB, and the downregulated NF-κB reduced miR-21-5p expression. In addition, miR-21-5p dramatically inhibited the target gene expression of programmed cell death protein 4 (PDCD4). In the current study, we demonstrated the potential anticancer effects of Andro on luminal-like breast cancer and indicated that Andro inhibits the expression of miR-21-5p and further promotes PDCD4 via NF-κB suppression. Therefore, Andro could be an antitumor agent for the treatment of luminal-like breast cancer in the clinic.

LncRNA Gas5 regulates Fn1 deposition via Creb5 in renal fibrosis

Aim: Although studies on lncRNAs in renal fibrosis have focused on target genes and functions of lncRNAs, a comprehensive interaction analysis of lncRNAs is lacking. Materials & methods: Differentially expressed genes in renal fibrosis were screened, and the interaction between lncRNAs and miRNAs was searched. Results: We constructed a ceRNA network associated with renal fibrosis, by which we found the transcription factor Creb5, a target gene of lncRNA Gas5 that might regulate extracellular Fn1 deposition. Conclusion: Our study not only provides a theoretical basis for the ceRNA regulation mechanism of Gas5 but also provides experimental evidence supporting the use of Gas5 targeting in the treatment of renal fibrosis.

ACE2 and Furin Expressions in Oral Epithelial Cells Possibly Facilitate COVID-19 Infection via Respiratory and Fecal-Oral Routes

Background: Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that mainly transfers from human to human via respiratory and gastrointestinal routes. The S-glycoprotein in the virus is the key factor for the entry of SARS-CoV-2 into the cell, which contains two functional domains: S1 is an angiotensin-converting enzyme 2 (ACE2) receptor binding domain, and S2 is necessary for fusion of the coronavirus and cell membranes. Moreover, it has been reported that ACE2 is likely to be the receptor for SARS-CoV-2. In addition, mRNA level expression of Furin enzyme and ACE2 receptor had been reported in airway epithelia, cardiac tissue, and enteric canals. However, the expression patterns of ACE2 and Furin in different cell types of oral tissues are still unclear. Methods: In order to investigate the potential infective channel of the new coronavirus via the oropharyngeal cavity, we analyze the expression of ACE2 and Furin in human oral mucosa using the public single-cell sequence datasets. Furthermore, immunohistochemistry was performed in mucosal tissue from different oral anatomical sites to confirm the expression of ACE2 and Furin at the protein level. Results: The bioinformatics results indicated the differential expression of ACE2 and Furin on epithelial cells from different oral anatomical sites. Immunohistochemistry results revealed that both the ACE2-positive and Furin-positive cells in the target tissues were mainly positioned in the epithelial layers, partly expressed in fibroblasts, further confirming the bioinformatics results. Conclusions: Based on these findings, we speculated that SARS-CoV-2 could invade oral mucosal cells through two possible routes: binding to the ACE2 receptor and fusion with cell membrane activated by Furin protease. Our results indicated that oral mucosa tissues are susceptible to SARS-CoV-2 that could facilitate COVID-19 infection via respiratory and fecal-oral routes.

Π electron-stabilized polymeric micelles potentiate docetaxel therapy in advanced-stage gastrointestinal cancer

Gastrointestinal (GI) cancers are among the most lethal malignancies. The treatment of advanced-stage GI cancer involves standard chemotherapeutic drugs, such as docetaxel, as well as targeted therapeutics and immunomodulatory agents, all of which are only moderately effective. We here show that Π electron-stabilized polymeric micelles based on PEG-b-p(HPMAm-Bz) can be loaded highly efficiently with docetaxel (loading capacity up to 23 wt%) and potentiate chemotherapy responses in multiple advanced-stage GI cancer mouse models. Complete cures and full tumor regression were achieved upon intravenously administering micellar docetaxel in subcutaneous gastric cancer cell line-derived xenografts (CDX), as well as in CDX models with intraperitoneal and lung metastases. Nanoformulated docetaxel also outperformed conventional docetaxel in a patient-derived xenograft (PDX) model, doubling the extent of tumor growth inhibition. Furthermore, micellar docetaxel modulated the tumor immune microenvironment in CDX and PDX tumors, increasing the ratio between M1-and M2-like macrophages, and toxicologically, it was found to be very well-tolerated. These findings demonstrate that Π electron-stabilized polymeric micelles loaded with docetaxel hold significant potential for the treatment of advanced-stage GI cancers.

Slit2/Robo1 Mitigates DSS-induced Ulcerative Colitis by Activating Autophagy in Intestinal Stem Cell

Ulcerative colitis (UC) is a recurrent intestinal inflammatory disease. Slit2, a secreted protein, interacts with its receptor Robo1 to regulate the differentiation of intestinal stem cells and participate in inflammation and tumor development. However, whether Slit2/Robo1involved in the pathogenesis of UC is not known. We investigated Slit2/Robo1-mediated UC using a dextran sodium sulfate (DSS)-induced model. Eight-week-old male Slit2-Tg (Slit2 transgene) mice, Robo1/2+/- (Robo1+/- Robo2+/-) mice, and their WT littermates were allocated into two groups: (I) control group (n=10), of mice fed a normal diet and tap water and (II) DSS group (n=10), of mice fed a normal diet and drinking water with 2% DSS for 7 days. Colon tissues were collected and analyzed by qPCR, immunohistochemistry, western blot, and immunofluorescence. Slit2-Tg DSS mice showed less body weight loss, less blood in the stool, and less viscous stool compared to those of WTSlit DSS mice. Robo1/2+/- DSS mice displayed a heavier degree of blood in the stool and a more apparent viscosity of the stool compared to those of WTRobo1/2 DSS mice. Slit2 overexpression maintained Lgr5+ stem cell proliferation in the crypt after DSS treatment, significantly increased the LC3II/I ratio, and slightly stimulated p62 expression in the crypt compared to those of DSS-induced WTSlit mice. Robo1/2 partial knockout reduced the number of Lgr5+ stem cells, decreased the LC3II/I ratio, and markedly increased p62 expression in the crypt compare to those of DSS-treated WTRobo1/2 mice. Our findings suggest that Slit2/Robo1 mediates DSS-induced UC probably by activating the autophagy of Lgr5+ stem cells.

Knocking out matrix metalloproteinase 12 causes the accumulation of M2 macrophages in intestinal tumor microenvironment of mice

MMP12 is mainly secreted by macrophages, is involved in macrophage development, and decomposes the extracellular matrix. Herein, we investigated whether macrophages would change in the intestinal tumor microenvironment after MMP12 knockout. Apc^Min/+;MMP12^-/-mice were obtained by crossbreeding Apc^Min/+ mice with MMP12 knockout mice (MMP12^-/- mice). The data showed that the number and volume of intestinal tumors were significantly increased in Apc^Min/+;MMP12^-/- mice compared with Apc^Min/+ mice. Additionally, the tumor biomarkers CA19-9, CEA, and β-catenin appeared relatively early in intestinal tumors in Apc^Min/+;MMP12^-/- mice. The results demonstrated that knocking out MMP12 accelerated the tumor growth and pathological process. On further investigation of its mechanism, the proportions of M2 macrophages in the spleen and among peritoneal macrophages were significantly up-regulated in Apc^Min/+;MMP12^-/- mice. Expression of M2 macrophage-related genes was up-regulated in tumor and peritoneal macrophages. The M2-related cytokine levels of IL-4 and IL-13 were increased in the serum of Apc^Min/+;MMP12^-/-mice. In vitro, bone marrow-derived M2 macrophages were obtained by treating bone marrow cells with IL-4 and IL-13, and these M2 macrophages secreted cytokines being changed. This finding reveals the crucial role of MMP12 in macrophage development and provides a new target for the control of macrophage polarization. Knocking out MMP12 causes intestinal M2 macrophage accumulation in tumor microenvironment, promoting the growth of intestinal tumors in Apc^Min/+ mice.

Decylubiquinone suppresses breast cancer growth and metastasis by inhibiting angiogenesis via the ROS/p53/ BAI1 signaling pathway

Breast cancer is one of the most common cancers worldwide with a rising incidence, and is the leading cause of cancer-related death among females. Angiogenesis plays an important role in breast cancer growth and metastasis. In this study, we identify decylubiquinone (DUb), a coenzyme Q₁₀ analog, as a promising anti-breast cancer agent through suppressing tumor-induced angiogenesis. We screened a library comprising FDA-approved drugs and found that DUb significantly inhibits blood vessel formation using in vivo chick embryo chorioallantoic membrane (CAM) and yolk sac membrane (YSM) models. DUb was further identified to inhibit angiogenesis in the rat aortic ring and Matrigel plug assay. Moreover, DUb was found to suppress breast cancer growth and metastasis in the MMTV-PyMT transgenic mouse and human xenograft tumor models. To explore whether the anticancer efficacy of DUb was directly corrected with tumor-induced angiogenesis, the MDA-MB-231 breast cancer assay on the CAM was performed. Interestingly, DUb significantly inhibits the angiogenesis of breast cancer on the CAM. Brain angiogenesis inhibitor 1 (BAI1), a member of the G protein-coupled receptor (GPCR) adhesion subfamily, has an important effect on the inhibition of angiogenesis. Further studies demonstrate that DUb suppresses the formation of tubular structures by regulating the reactive oxygen species (ROS)/p53/BAI1 signaling pathway. These results uncover a novel finding that DUb has the potential to be an effective agent for the treatment of breast cancer by inhibiting tumor-induced angiogenesis.

R5, a neutralizing antibody to Robo1, suppresses breast cancer growth and metastasis by inhibiting angiogenesis via down-regulating filamin A

Breast cancer (BC) is one of the most common cancers among women in both developed and developing countries with a rising incidence. Using the MMTV-PyMT transgenic mouse model and xenografted breast cancer model, we found that R5, a neutralizing antibody to Robo1, significantly inhibited BC growth and metastasis. Angiogenesis is involved in the growth and metastasis of BC. Interestingly, R5 significantly decreases microvessel density in BC tissues, and inhibits blood vessel formation and development in in vivo chick embryo chorioallantoic membrane (CAM), yolk sac membrane (YSM) and Matrigel plug models. To investigate whether its anti-breast cancer efficacy is ascribed to its direct antiangiogenic properties, xenografted breast cancer model on CAM was established. Furthermore, R5 significantly reduces the tube formation of the vascular plexus on xenografted breast tumor on CAM. R5 also suppresses the migration and the tubular structure formation of human umbilical vein endothelial cells (HUVECs) by down-regulating the expression of filamin A (FLNA). These findings show that R5 has the potential to be a promising agent for the treatment of BC by suppressing the tumor-induced angiogenesis.

Activation of Slit2/Robo1 Signaling Promotes Tumor Metastasis in Colorectal Carcinoma through Activation of the TGF-β/Smads Pathway

Slit2 (slit guidance ligand 2), a ligand of the Roundabout1 (Robo1) transmembrane receptor, is often overexpressed in colorectal carcinomas (CRCs). In this study, we performed data mining in the Metabolic gEne RApid Visualizer (MERAV) database and found that Slit2 and TGF-β1 (Transforming growth factor-β1) are highly expressed in carcinomas relative to those in tumor-free tissues from healthy volunteers or wild type mice. Furthermore, expression of Slit2 and TGF-β1 in CRCs increases with pathological stages. Serum levels of Slit2 in patients with CRC and in ApcMin/+ mice with spontaneous intestinal adenoma were significantly increased compared with those in healthy controls. Specific blockage of Slit2 binding to Robo1 inactivated TGF-β/Smads signaling and inhibited tumor cell migration and metastasis, which can be partially restored by treatment with TGF-β1. However, specific inhibition of TGF-β1/Smads signaling reduced CRC tumor cell migration and invasion without affecting cell proliferation. This study suggests that activation of Slit2/Robo1 signaling in CRC induces tumor metastasis partially through activation of the TGF-β/Smads pathway.

HMGA1 Overexpression is Associated With the Malignant Status and Progression of Breast Cancer

Breast cancer is the most common malignant tumor among women, and the incidence and mortality of breast cancer has rapidly increased in recent years. Studies have indicated that high mobility group A1 (HMGA1), an important member of the HMGA family, plays a role in the pathogenesis and progression of malignant tumors, including breast cancer. This study aims to evaluate the effect of HMGA1 in breast cancer. Interestingly, we found that HMGA1 expression was significantly higher in breast cancer tissues than in adenoma tissues and closely correlated with the clinical stage and histological grade in breast cancer patients. Further study showed that HMGA1 knockdown inhibited the proliferation and migration of breast cancer cells. Thus, the results demonstrated that HMGA1 could act as an independent prognostic indicator in breast cancer. HMGA1 expression was closely correlated with the clinical stage, histological grade, and tumor size in breast cancer patients and breast cancer progression in transgenic MMTV-PyMT mice. Anat Rec, 301:1061-1067, 2018. © 2018 Wiley Periodicals, Inc.

Human colorectal cancer progression correlates with LOX-induced ECM stiffening

Some solid tumors are characterized by extracellular matrix (ECM) remodeling and stiffening, which is related to solid tumor progression and aggression. However, the relationship between ECM stiffness and colorectal cancer (CRC) remains unclear. In this study, we investigated the relevance of ECM stiffness to clinicopathologic features using human CRC tissue microarrays. The results demonstrate that the expression of ECM components in CRC tissues is closely correlated with CRC progression and poor prognosis, which indicates that ECM stiffness may be associated with CRC development. We further studied lysyl oxidase (LOX) expression in CRC tissue and demonstrated that LOX expression is closely correlated with CRC progression. Previous studies showed that P-selectin-mediated platelet accumulation in CRC tissue may up-regulate LOX expression. Our findings indicate that P-selectin-mediated platelet aggregation may up-regulate LOX expression and enhance the remodeling and stiffening of the tumor ECM, which may promote the progression of colorectal cancer. Therefore, LOX may be a potential effective therapeutic target to treat colorectal cancer.

[The value of urinary neutrophil gelatinase-associated lipocalin for early diagnosis of contrast-induced nephropathy]

Objective: To explore the value of urinary neutrophil gelatinase-associated lipocalin (NGAL) for early diagnosis of contrast-induced nephropathy (CIN) in patients who underwent percutaneous coronary angiography (CAG) or percutaneous coronary intervention (PCI). Methods: From May 2015 to January 2016, 506 consecutive patients who underwent CAG or PCI in our hospital were enrolled in this prospective study. Patients were divided into CIN group (n=47) and non-CIN group (n=459). Clinical and interventional data were compared between the two groups. Spearman ranking correlation coefficient was used to define the relation between NGAL and CIN, and multivariable logistic regression analysis was performed to identif independent predictors of CIN. Receiver-operator characteristic (ROC) curve was generated, and area under the curve (AUC) was calculated and sensitivity and specificity for CIN diagnosis were analyzed. Results: (1) Basic clinical and interventional data including age, incidence of diabetes, hypertension and chronic heart failure, level of systolic blood pressure, serum creatine before procedure, use of isotonic contrast agent, contrast volume, Mehran score, operation time, treatment number of coronary artery, hydration and medication were all similar between two groups (all P>0.05). (2) Urinary NAGL level at 24 and 48 h after procedure, serum creatinine (Scr) level at 48 h after procedure, and ΔNGAL_{24-0 h} were significantly higher in CIN group than in non-CIN group (all P<0.01), but the differences of urinary NGAL level before procedure, Scr level 24 h after procedure, and ΔNGAL_{48-24 h} were similar between two groups (all P>0.05). (3)The positive correlation was found by Spearman ranking correlation between ΔNGAL_{24-0 h} and CIN (r=0.478, P<0.001). (4) Multivariable logistic regression analysis showed that estimated glomerular filtration rate(OR=1.020, 95%CI 1.005-1.035, P=0.007) and ΔNGAL_{24-0 h} (OR=1.020, 95%CI 1.014-1.027, P<0.001) were the independent predictors of CIN.(5) ROC curve showed that the AUC of NGAL with the cutoff value 4.65 was 0.899(0.854, 0.944)for diagnosis of CIN (sensitivity 93.6%, and specificity 0.944). Conclusion: The rise of urinary NGAL level at 24 and 48 hours after CAG or PCI is suggestive of CIN and could be used as a reliable parameter for the early diagnose of CIN.

P-selectin-mediated LOX expression promotes insulinoma growth in Rip1-Tag2 mice by increasing tissue stiffness

P-selectin, a cell adhesion molecule, is an important member of the selectin family. Recent studies have shown that P-selectin deletion inhibits tumor growth in Rip1-Tag2 mice by suppressing platelet accumulation in tumor tissues. This study aimed to evaluate whether and how P-selectin affects tumor stiffness in Rip1-Tag2 mice. To explore the role of P-selectin in tissue stiffness, we demonstrated that tumor progression in Rip1-Tag2 mice was correlated with tissue stiffness using immunofluorescence and histological staining. Furthermore, we showed that P-selectin deficiency significantly decreased tissue stiffness by inhibiting lysyl oxidase (LOX) expression. Our experiments involving Rip1-Tag2 mice treated with the LOX inhibitor BAPN showed that BAPN significantly abolished collagen deposition to decrease tumor stiffness and thus inhibit tumor growth. These results indicate that P-selectin deletion significantly decreases tumor stiffness in Rip1-Tag2 mice by inhibiting LOX expression. Further study demonstrated that P-selectin-mediated platelet accumulation increases tissue stiffness mainly by increasing LOX expression and thus promotes tumor growth. Therefore, P-selectin may be an effective therapeutic targeting for treating human insulinomas.

Glipizide suppresses prostate cancer progression in the TRAMP model by inhibiting angiogenesis

Drug repurposing of non-cancer drugs represents an attractive approach to develop new cancer therapy. Using the TRAMP transgenic mouse model, glipizide, a widely used drug for type 2 diabetes mellitus, has been identified to suppress prostate cancer (PC) growth and metastasis. Angiogenesis is intimately associated with various human cancer developments. Intriguingly, glipizide significantly reduces microvessel density in PC tumor tissues, while not inhibiting prostate cancer cell proliferation from the MTT assay and flow cytometry investigation. Moreover, glipizide inhibits the tubular structure formation of human umbilical vein endothelial cells by regulating the HMGIY/Angiopoietin-1 signaling pathway. Taken together, these results demonstrate that glipizide has the potential to be repurposed as an effective therapeutic for the treatment of PC by targeting tumor-induced angiogenesis.

Activation of Slit2-Robo1 signaling promotes liver fibrosis

BACKGROUND & AIMS

The secretory protein Slit2 and its receptor Robo1 are believed to regulate cell growth and migration. Here, we aimed to determine whether Slit2-Robo1 signaling mediates the pathogenesis of liver fibrosis.

METHODS

Serum levels of Slit2 in patients with liver fibrosis were determined by ELISA. Liver fibrosis was induced in wild-type (WT), Slit2 transgenic (Slit2-Tg) and Robo1(+/-)Robo2(+/-) double heterozygotes (Robo1/2(+/-)) mice by carbon tetrachloride (CCl4). The functional contributions of Slit2-Robo1 signaling in liver fibrosis and activation of hepatic stellate cells (HSCs) were investigated using primary mouse HSCs and human HSC cell line LX-2.

RESULTS

Significantly increased serum Slit2 levels and hepatic expression of Slit2 and Robo1 were observed in patients with liver fibrosis. Compared to WT mice, Slit2-Tg mice were much more vulnerable to CCl4-induced liver injury and more readily develop liver fibrosis. Development of hepatic fibrosis in Slit2-Tg mice was associated with a stronger hepatic expression of collagen I and α-smooth muscle actin (α-SMA). However, liver injury and hepatic expression of collagen I and α-SMA were attenuated in CCl4-treated Robo1/2(+/-) mice in response to CCl4 exposure. In vitro, Robo1 neutralizing antibody R5 and Robo1 siRNA downregulated phosphorylation of Smad2, Smad3, PI3K, and AKT in HSCs independent of TGF-β1. R5 and Robo1 siRNA also inhibited the expression of α-SMA by HSCs. Finally, the protective effect of R5 on the CCl4-induced liver injury and fibrosis was further verified in mice.

CONCLUSIONS

Slit2-Robo1 signaling promotes liver injury and fibrosis through activation of HSCs.

Glipizide, an antidiabetic drug, suppresses tumor growth and metastasis by inhibiting angiogenesis

Angiogenesis is involved in the development, progression and metastasis of various human cancers. Herein, we report the discovery of glipizide, a widely used drug for type 2 diabetes mellitus, as a promising anticancer agent through the inhibition of tumor angiogenesis. By high-throughput screening (HTS) of an FDA approved drug library utilizing our in vivo chick embryo chorioallantoic membrane (CAM) and yolk sac membrane (YSM) models, glipizide has been identified to significantly inhibit blood vessel formation and development. Moreover, glipizide was found to suppress tumor angiogenesis, tumor growth and metastasis using xenograft tumor and MMTV-PyMT transgenic mouse models. We further revealed that the anticancer capability of glipizide is not attributed to its antiproliferative effects, which are not significant against various human cancer cell lines. To investigate whether its anticancer efficacy is associated with the glucose level alteration induced by glipizide application, glimepiride, another medium to long-acting sulfonylurea antidiabetic drug in the same class, was employed for the comparison studies in the same fashion. Interestingly, glimepiride has demonstrated no significant impact on the tumor growth and metastasis, indicating that the anticancer effects of glipizide is not ascribed to its antidiabetic properties. Furthermore, glipizide suppresses endothelial cell migration and the formation of tubular structures, thereby inhibiting angiogenesis by up-regulating the expression of natriuretic peptide receptor A. These findings uncover a novel mechanism of glipizide as a potential cancer therapy, and also for the first time, provide direct evidence to support that treatment with glipizide may reduce the cancer risk for diabetic patients.

Increased permeability of the blood-brain barrier and Alzheimer's disease-like alterations in slit-2 transgenic mice

Alzheimer's disease (AD) is a progressive neurological disorder that primarily affects memory, and its prevalence is rising. Increasing evidence suggests that dysfunction of the blood-brain barrier (BBB) may be involved in AD and other neurodegenerative diseases. Herein, we report that the permeability of the BBB is increased and that AD-like alterations are present in Slit-2 overexpressing transgenic mice. We found that behavioral change and the corresponding molecular diagnostic markers of AD, such as hippocampal neuron apoptosis, amyloid-β (Aβ) protein deposition, and acetylcholinesterase expression, were increased in the Slit-2 transgenic mice. Moreover, the endothelial cells were dysfunctional, the size of the lateral ventricle cavity increased, and the permeability of the BBB increased. Additionally, there was an increased serum level of glutamate indicating that the BBB is related to AD. Finally, histopathological analysis of other organs in the Slit-2 overexpressing mice did not show any marked abnormalities. These findings demonstrate that Slit2 overexpression may be responsible for AD-like alterations and the increased BBB permeability in these mice. Our study provides a potential novel mechanism for the development of AD.

MicroRNA-29b attenuates non-small cell lung cancer metastasis by targeting matrix metalloproteinase 2 and PTEN

BACKGROUND

Our pilot study using miRNA PCR array found that miRNA-29b (miR-29b) is differentially expressed in primary cultured CD133-positive A549 cells compared with CD133-negative A549 cells.

METHODS

Ten human non-small cell lung cancer (NSCLC) cell lines and samples from thirty patients with NSCLC were analyzed for the expression of miR-29b by quantitative RT-PCR. Bioinformatics analysis combined with tumor metastasis PCR array showed the potential target genes for miR-29b. miR-29b lentivirus and inhibitors were transfected into NSCLC cells to investigate its role on regulating cell proliferation which was measured by CCK-8 assay in vitro and nude mice xenograft tumor assay in vivo. Cell motility ability was evaluated by transwell assay. The target genes of miR-29b were determined by luciferase assay, quantitative RT-PCR and western blot.

RESULTS

Bioinformatics analysis combined with tumor metastasis PCR array showed that matrix metalloproteinase 2 (MMP2) and PTEN could be important target genes of miR-29b. The expression of miR-29b was down regulated in NSCLC tissues compared to the normal tissues. Clinicopathological analysis demonstrated that miR-29b had significant negative correlation with lymphatic metastasis. The gain-of-function studies revealed that ectopic expression of miR-29b decreased cell proliferation, migration and invasion abilities of NSCLC cells. In contrasts, loss-of-function studies showed that inhibition of miR-29b promoted cell proliferation, migration and invasion of NSCLC cells in vitro. Nude mice xenograft tumor assay confirmed that miR-29b inhibited lung cancer growth in vivo. High-invasion (A549-H) and low-invasion (A549-L) NSCLC cell sublines from A549 cells were created by using the repeated transwell assay aimed to confirm the effect of miR-29b on migration and invasion of NSCLC. Furthermore, the dual-luciferase reporter assay demonstrated that miR-29b inhibited the expression of the luciferase gene containing the 3'-UTRs of MMP2 and PTEN mRNA. Western blotting and quantitative RT-PCR indicated that miR-29b down-regulated the expression of MMP2 at the protein and mRNA levels.

CONCLUSION

Taken together, our results demonstrate that miR-29b serves as a tumor metastasis suppressor, which suppresses NSCLC cell metastasis by directly inhibiting MMP2 expression. The results show that miR-29b may be a novel therapeutic candidate target to slow NSCLC metastasis.

P-Selectin-Mediated Adhesion between Platelets and Tumor Cells Promotes Intestinal Tumorigenesis in Apc(Min/+) Mice

Studies have indicated that platelets play an important role in tumorigenesis, and an abundance of platelets accumulate in the ovarian tumor microenvironment outside the vasculature. However, whether cancer cells recruit platelets within intestinal tumors and how they signal adherent platelets to enter intestinal tumor tissues remain unknown. Here, we unexpectedly found that large numbers of platelets were deposited within human colorectal tumor specimens using immunohistochemical staining, and these platelets were fully associated with tumor development. We further report the robust adhesion of platelet aggregates to tumor cells within intestinal tumors, which occurs via a mechanism that is dependent on P-selectin (CD62P), a cell adhesion molecule that is abundantly expressed on activated platelets. Using spontaneous intestinal tumor mouse models, we determined that the genetic deletion of P-selectin suppressed intestinal tumor growth, which was rescued by the infusion of wild-type platelets but not P-selectin^-/- platelets. Mechanistically, platelet adhesion to tumor cells induced the secretion of vascular endothelial growth factor (VEGF) to promote angiogenesis and accelerate intestinal tumor cell proliferation. Our results indicate that the adherence of platelets to tumor cells could promote tumor growth and metastasis. By targeting this platelet-tumor cell interaction, recombinant soluble P-selectin may have therapeutic value for the treatment of intestinal tumors.

P-selectin-mediated platelet adhesion promotes tumor growth

Blood platelets foster carcinogenesis. We found that platelets are accumulated in human tumors. P-selectin deficiency and soluble P-selectin abolish platelet deposition within tumors, decreasing secretion of vascular endothelial growth factor and angiogenesis, thereby suppressing tumor growth. Binding of the P-selectin cytoplasmic tail to talin1 triggers the talin1 N-terminal head to interact with the β3 cytoplasmic tail. This activates αIIbβ3 and recruits platelets into tumors. Platelet infiltration into solid tumors occurs through a P-selectin-dependent mechanism.

Glipizide suppresses embryonic vasculogenesis and angiogenesis through targeting natriuretic peptide receptor A

Glipizide, a second-generation sulfonylurea, has been widely used for the treatment of type 2 diabetes. However, it is controversial whether or not glipizide would affect angiogenesis or vasculogenesis. In the present study, we used early chick embryo model to investigate the effect of glipizide on angiogenesis and vasculogenesis, which are the two major processes for embryonic vasculature formation as well as tumor neovascularization. We found that Glipizide suppressed both angiogenesis in yolk-sac membrane (YSM) and blood island formation during developmental vasculogenesis. Glipizide did not affect either the process of epithelial to mesenchymal transition (EMT) or mesoderm cell migration. In addition, it did not interfere with separation of smooth muscle cell progenitors from hemangioblasts. Moreover, natriuretic peptide receptor A (NPRA) has been identified as the putative target for glipizide׳s inhibitory effect on vasculogenesis. When NPRA was overexpressed or activated, blood island formation was reduced. NPRA signaling may play a crucial role in the effect of glipizide on vasculogenesis during early embryonic development.

Inactivation of PI3Kδ induces vascular injury and promotes aneurysm development by upregulating the AP-1/MMP-12 pathway in macrophages

OBJECTIVE

An aneurysm is an inflammatory vascular condition. Phosphatidylinositol 3-kinases δ is highly expressed in leukocytes, and play a key role in innate immunity. However, the link between phosphatidylinositol 3-kinases δ and aneurysm development has not yet been elucidated.

APPROACH AND RESULTS

Carotid ligation unexpectedly induced characteristic aneurysm formation beneath the ligation point in p110δ(D910A/D910A) mice (n=25; P<0.001 versus wild-type). Besides, p110δ inactivation exacerbated CaCl2-induced abdominal aortic aneurysms development. A reverse transcription polymerase chain reaction microarray revealed significant extracellular matrix components degradation and matrix metalloproteinases (MMPs) upregulation in the abdominal aorta of p110δ(D910A/D910A) mice. Similarly, the expression of both collagen I and IV was significantly decreased (n=10; P<0.05 versus wild-type) in carotid artery. Western blot assay confirmed that MMP-12 was significantly upregulated in arteries of p110δ(D910A/D910A) mice (n=10; P<0.01 versus wild-type). In vitro, p110δ inactivation marked increase peritoneal macrophages recruitment and synergistically enhance tumor necrosis factor-α-induced recruitment. A specific phosphatidylinositol 3-kinases δ inhibitor (IC87114) or genetic p110δ inactivation upregulated MMP-12 expression and c-Jun phosphorylation (n=6; P<0.05 versus wild-type macrophages). IC87114 also increased activator protein-1 DNA-binding activity (n=6; P<0.001 versus control) and enhanced the effect of tumor necrosis factor-α on activator protein-1-binding activity (n=5; P<0.01 versus tumor necrosis factor-α treatment groups). Knockdown of c-Jun suppressed the effect of the IC87114 and tumor necrosis factor-α on MMP-12 mRNA expression (n=5 in each group; P<0.01 versus scrRNA treatment groups).

CONCLUSIONS

Our findings demonstrate that p110δ inactivation leads to extracellular matrix degradation in vessels and promotes aneurysm development by inducing macrophages migration and upregulating the activator protein-1/MMP-12 pathway in macrophages.

[Type I collagen secreted by lung cancer cells promotes cancer cell growth in a three- dimensional culture system]

OBJECTIVE

To investigate the role of type I collagen as an autocrine protein in promoting the growth lung cancer cells in a three-dimensional (3D) culture system.

METHODS

Immunohistochemistry and RT-PCR were used to detect the expression of type I collagen in lung cancer specimens and 5 lung cancer cell lines. The lung cancer cell lines in 3D cultures were treated with vectors harboring short hairpin RNA (shRNA) targeting type I collagen, and the cell growth suppression was evaluated using MTT assay and colony formation assay. The lung cancer cells stimulated with supernatant from lung cancer-derived fibroblasts were tested for the expression of type I collagen mRNA.

RESULTS

Type I collagen expressions were detected in both the lung cancer tissues and the cell lines. In the 3D culture system, the growth of the cancer cell lines was obviously suppressed by shRNA-mediated type I collagen knockdown evidenced by lowered cell growth rate and colony formation ability. Stimulation with fibroblast culture supernatant resulted in enhanced expressions of type I collagen in the cancer cell lines.

CONCLUSION

Autocrine of type I collagen I is required for maintaining lung cancer cell growth in 3D cultures, and its expression is regulated by fibroblasts. These findings provide new insights into the role of type I collagen I in the tumor microenvironment and point a new direction for targeted therapy of tumors.

Micrometastasis expressing insulin arise in lung and spleen at advanced stage of rip1-tag2 transgenic mice

Rip1-Tag2 mice is one overt pancreatic β-cell tumor model, which is widely used for studying pancreas tumor angiogenesis and tumor development. However, tumor metastasis in Rip1-Tag2 mice had rarely been reported, in this present study, we find some micrometastasis in lung and spleen of the Rip1-Tag2 mice at advanced stage, which is important for uncovering metastasis cell characteristics and exploring how to survive in cancer microenvironment. To study the micrometastasis of Rip1-Tag2 mice in advanced pancreatic cancer, we first observed the pathology process of β cell tumor in Rip1-Tag2 mice through HE staining, then we performed immunohistochemistry with insulin antibody, T-antigen antibodies and C-petide antibody on lung and spleen tissues sections from advanced stage, comparing with background wild-type C57BL/6 mice sections. The results indicated that micrometastasis expressing insulin was found in the Rip1-Tag2 mice lung, and spleen. Further evidences demonstrate pathology structure of lung and spleen are damaged. Interestingly and importantly, the expression of T antigen and insulin antibodies are all decreased in advanced stage of primary β cell tumor, which suggest that the at least partly micrometastasis is derived from the early stage or from advanced stage of β cell tumor then return to undifferentiated state like cancer stem cell. The findings contributed to the study of cancer metastasis and cancer stem cell.

[Role of Slit-Robo signaling in the proliferation of human mucoepidermoid carcinoma Mc3 cells]

OBJECTIVE

To study the role of Slit-Robo signaling in the proliferation of human mucoepidermoid carcinoma Mc3 cells.

METHODS

We measured the expressions of Slit2 and Robo1 proteins in human mucoepidermoid carcinoma Mc3 cells using immunohistochemistry and flow cytometry. To test the role of Slit-Robo signaling in the proliferation of the cells, we treated the cells with the monoclonal antibody R5 against Robo1 receptor extracellular domain and observed the changes in the cell proliferation by cell counting and colonogenic assay; the expression of proliferating cell nuclear antigen (PCNA) in the cells following the treatment was measured with flow cytometry.

RESULTS

Treatment of Mc3 cells with the monoclonal antibody R5 caused significantly suppressed cell growth and proliferation and obviously lowered the expression of PCNA.

CONCLUSION

Slit-Robo signaling can suppress the proliferation of Mc3 cells possibly by up-regulating the expression of PCNA.

[Rational evaluation of different lymph node dissection]

To evaluate the effect and indication of different lymph node dissection (D1+, D2, D3), we performed radical operations for 371 cases of gastric cancer. The results showed that D1+ or D1 lymph node dissection was enough for gastric cancer of Ia stage, D2 was suitable for Ib stage. For localized or massive type gastric cancer of II + III stage, D3, D2 dissection was better than D1+ dissection. For the gastric cancer of the same type in IV stage, the 5-year survival rate after D3 + D2 dissection was 42.9%, but for the gastric cancer of infiltrative type or diffused growth pattern in II + III stage, the effect was not significantly increased even after the D3, D2 dissection. For the gastric cancer of this type in IV stage, the effect was not improved after the extended lymph node dissection. Extended dissection needn't be performed if there was no lymph node metastasis. D3, D2 dissection was better if there was little lymph node metastasis or the metastasis was limited to 1st group. For those metastasized to 2nd group or the quantity was more, D3 was better than D2, D1+. The effect of D3, D2 dissection was not significantly improved in the extensive metastasis case (more than 10 or to the 3rd group).

[Indication of radical surgery (R2, R3) based upon the pattern of lymph node metastasis from gastric cancer]

From Jan. 1980 to June. 1984, radical operation was performed in 156 patients with gastric cancer according to the "protocol" introduced by the Gastric Cancer Research Society of Japan. There were 24 early and 132 advanced gastric cancers. Seventy patients were treated by type R2, 86 by R+2 and R3. Radical distal subtotal gastrectomy was done in 116, proximal subtotal gastrectomy in 7, simple total gastrectomy in 13 and subtotal or total gastrectomy combined with neighbouring organ resection in 20. According to TNM staging, 24 (15.4%) lesions were stage I, 9 (5.8%) stage II, 100 (64.1%) stage III and 23 (14.7%) stage IV. Twenty four lesions were within the mucosa or submucosal layer, 11 in proprius muscle layer, 18 to subserosa, 15 to serosa, 46 beyond serosa, 42 involving the surrounding organs. Lymph node metastatic rate was 66% (103 cases), metastatic degree was 21.5% (558/2593). The metastatic degree of lymph node line I, II and III was 24.7%, 20% and 8.3%, respectively. Basing on lymph node metastatic rate and degree as well as the line degree, it is proposed that, in the early stage of gastric cancer, type R1 be performed for cancer limited to the mucosa, especially the minute type, R2 for cancer invading the submucosa, in which, R+2 be indicated for some isolated patients. In the advanced gastric cancer, type R+2 be performed in the majority of patients and R3 in a few. R3 or total gastrectomy combined with neighbouring organ resection be carried out only in a part of cases with the limited type infiltrating beyond the serosa or invading the neighbouring organs.