Boyden Chamber Invasion Assay Research Articles

Hypoxia- and Postirradiation reoxygenation-induced HMHA1/ARHGAP45 expression contributes to cancer cell invasion in a HIF-dependent manner

BackgroundCancer cells in severely hypoxic regions have been reported to invade towards tumour blood vessels after surviving radiotherapy in a postirradiation reoxygenation- and hypoxia-inducible factor (HIF)-dependent manner and cause recurrence. However, how HIF induces invasiveness of irradiated and reoxygenated cancer cells remains unclear.MethodsHere, we identified human minor histocompatibility antigen 1 (HMHA1), which has been suggested to function in cytoskeleton dynamics and cellular motility, as a responsible factor and elucidated its mechanism of action using molecular and cellular biology techniques.ResultsHMHA1 expression was found to be induced at the transcription initiation level in a HIF-dependent manner under hypoxia. Boyden chamber invasion assay revealed that the induction of HMHA1 expression is required for the increase in invasion of hypoxic cancer cells. Reoxygenation treatment after ionising radiation in vitro that mimics dynamic changes of a microenvironment in hypoxic regions of tumour tissues after radiation therapy further enhanced HMHA1 expression and invasive potential of HMHA1 wildtype cancer cells in ROS- and HIF-dependent manners, but not of HMHA1 knockout cells.ConclusionThese results together provide insights into a potential molecular mechanism of the acquisition of invasiveness by hypoxic cancer cells after radiotherapy via the activation of the ROS/HIF/HMHA1 axis.

Abstract 3353: The emerging role of extracellular HSP90 in prostate cancer progression to a metastatic phenotype

Abstract Background: Metastasis is the central cause of lethal prostate cancer (PCa). Mechanisms regulating metastasis represent high-potential therapeutic targets for preventing development of lethal PCa. Inhibitors of extracellular heat shock protein 90 (eHSP90) have been shown to inhibit prostate cell motility. In contrast to the intracellular HSP90 (iHSP90), whose biology has been extensively studied, and whose therapeutic targeting is associated with systemic toxicity, the biology of extracellular HSP90 is not well understood. We undertook a series of investigations to better understand eHSP90 biology in PCa. Methods: Human PCa cells were subjected to cellular stress by heat shock combined with serum starvation. Resultant conditioned media was probed for matrix metalloproteinase 2 (MMP-2) by zymography and subject to scratch-wound and Boyden chamber invasion assays. Expression of HSP90 and CDC37 was measured by Western blot. Plasma from patients with PCa and healthy controls was probed for eHSP90 by ELISA. Results: We have examined expression of iHSP90 and eHSP90 after cellular stress, induced by heat shock and serum starvation, in human PC3, LNCaP, C4-2B, 1532NPTX and 1532CPTX PCa cell lines. Cell stress induces increased eHSP90 in all PCa cell lines examined. This is associated with a decrease in MMP-2 activity in conditioned media. Conditioned media from stressed cells was also shown to decrease invasion of PC3 cells, consistent with changes in MMP-2. Of high interest, the addition of protease inhibitors to conditioned media led to a complete reversal of the MMP-2 response: its activity increased with cellular stress. When measuring HSP90α in plasma from healthy controls (N = 20) and patients with PCa (N = 40, 20 localized and 20 metastatic), we demonstrated a significant (p=.001) >2 fold increase in PCa compared to control. Further, a significant increase in HSP90α was observed when low versus high T stage lesions were compared. There was no statistically significant difference in HSP90α for those with metastasis to regional lymph nodes, non-regional lymph nodes, bone, or liver. Conclusion: We demonstrate that increased eHSP90 due to cellular stress is a response observed across all PCa cell lines examined and should be considered typical. Its association with extracellular MMP-2 activity is dependent on the presence of other proteases and indicates a complex regulatory mechanism. Examination of eHSP90 in humans supports its association with aggressive disease. These factors support further investigation of underlying biology and therapeutic opportunities. Citation Format: Katelyn O'Neill, Johnny Zigmond, Raymond Bergan. The emerging role of extracellular HSP90 in prostate cancer progression to a metastatic phenotype [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3353.

Receptor tyrosine kinase-like orphan receptor 1 inhibitor strictinin exhibits anti-cancer properties against highly aggressive androgen-independent prostate cancer

Aim: It is important to identify anti-cancer compounds that can inhibit specific molecular targets to eradicate androgen-receptor negative (ARneg), androgen-independent (AI) prostate cancer, which is an aggressive form of prostate cancer with limited treatment options. The goal of this study was to selectively target prostate cancer cells that have high levels of oncogenic protein Receptor tyrosine kinase-like orphan receptor 1 (ROR1) by using strictinin, a small molecule ROR1 inhibitor. Methods: The methods performed in this study include western blots, methyl thiazolyl tetrazolium (MTT) proliferation assays, phosphatidylserine apoptosis assays, apoptosis flow cytometry (Annexin V, caspase 3/7), migration scratch assays, Boyden chamber invasion assays, and cell cycle flow cytometry. Results: Strictinin was most lethal against PC3 [half-maximal drug inhibitory concentration (IC50) of 277.2 µmol/L], an ARneg-AI cell type that expresses the highest levels of ROR1. Strictinin inhibited ROR1 expression, downstream phosphatidylinositol 3-kinase (PI3K)-protein kinase B (AKT)-glycogen synthase kinase 3beta (GSK3β) pro-survival signaling, and epithelial-to-mesenchymal transition markers in PC3 cells. Additionally, strictinin decreased PC3 cell migration and invasion, while increasing S-phase cell cycle arrest. In ARneg-AI DU145 cells, strictinin inhibited ROR1 expression and modulated downstream AKT-GSK3β signaling. Furthermore, strictinin exhibited anti-migratory, anti-invasive, but minimal pro-apoptotic effects in DU145 cells likely due to DU145 having less ROR1 expression in comparison to PC3 cells. Throughout the study, strictinin minimally impacted the phenotype of normal prostatic epithelial cells RWPE-1 (IC50 of 658.5 µmol/L). Strictinin was further identified as synergistic with docetaxel [combination index (CI) = 0.311] and the combination therapy was found to reduce the IC50 of strictinin to 38.71 µmol/L in PC3 cells. Conclusions: ROR1 is an emerging molecular target that can be utilized for treating prostate cancer. The data from this study establishes strictinin as a potential therapeutic agent that targets ARneg-AI prostate cancer with elevated ROR1 expression to reduce the migration, invasion, cell cycle progression, and survival of prostate cancer.

HERPUD1, a Member of the Endoplasmic Reticulum Protein Quality Control Mechanism, may be a Good Target for Suppressing Tumorigenesis in Breast Cancer Cells.

Breast cancer is the most frequently diagnosed cancer type and the second leading cause of cancer-related death in women. Recent studies have highlighted the importance of the endoplasmic reticulum (ER) protein quality control mechanism for the survival of many cancers. It has also been recommended as a good target for the treatment of many cancer types. Homocysteine inducible ER protein with ubiquitin-like domain 1 (HERPUD1) functions as one of the main components of ER-associated degradation, which is an ER-resident protein quality mechanism. Today, the association of HERPUD1 with breast carcinogenesis is still not fully understood. Herein, we evaluated the possibility of HERPUD1 as a potential therapeutic target for breast cancer. The effects of HERPUD1 silencing on epithelial-mesenchymal transition (EMT), angiogenesis, and cell cycle proteins were analyzed by immunoblotting studies. To test the role of HERPUD1 on tumorigenic features, WST-1-based cell proliferation assay, wound-healing assay, 2D colony formation assay, and Boyden-Chamber invasion assay were performed in human breast cancer cell line MCF-7. The statistical significance of the differences between the groups was determined by Student's t-test. Our results displayed that suppressing HERPUD1 expression reduced the cell cycle-related protein levels, including cyclin A2, cyclin B1, and cyclin E1 in MCF-7 cells. Also, silencing of HERPUD1 remarkably decreased expression levels of EMT-related N-cadherin and angiogenesis marker vascular endothelial growth factor A. Moreover, we determined that cell proliferation, migration, invasion, and colony formation of MCF-7 cells were significantly limited by silencing of HERPUD1. Present data suggest that HERPUD1 may be an effective target for biotechnological and pharmacological strategies to be developed to treat breast cancer.

Role of senescent tumor cells in building a cytokine shield in the tumor microenvironment: mathematical modeling.

Cellular senescence can induce dual effects (promotion or inhibition) on cancer progression. While immune cells naturally respond and migrate toward various chemotactic sources from the tumor mass, various factors including senescent tumor cells (STCs) in the tumor microenvironment may affect this chemotactic movement. In this work, we investigate the mutual interactions between the tumor cells and the immune cells that either inhibit or facilitate tumor growth by developing a mathematical model that consists of taxis-reaction-diffusion equations and receptor kinetics for the key players in the interaction network. We apply a mathematical model to a transwell Boyden chamber invasion assay used in the experiments to illustrate that STCs can play a pivotal role in negating immune attack through tight regulation of intra- and extra-cellular signaling molecules. In particular, we show that senescent tumor cells in cell cycle arrest can block intratumoral infiltration of CD8+ T cells by secreting a high level of CXCL12, which leads to significant reduction its receptors, CXCR4, on T cells, and thus impaired chemotaxis. The predictions of nonlinear responses to CXCL12 were in good agreement with experimental data. We tested several hypotheses on immune-tumor interactions under various biochemical conditions in the tumor microenvironment and developed new concepts for anti-tumor strategies targeting senescence induced immune impairment.

Investigation of the Molecular Mechanisms Underlying the Antiatherogenic Actions of Kaempferol in Human THP-1 Macrophages.

Cardiovascular disease (CVD) is causing high mortality worldwide (World Health Organization-WHO, 2015). Atherosclerosis, the hardening and narrowing of arteries caused by the accumulation of fatty acids and lipids (cholesterol plaques), is a main reason of stroke, myocardial infarction, and angina. Present therapies for cardiovascular disease basically use statins such as β-Hydroxy β-methylglutaryl-CoA, with <70% efficacy and multiple side effects. An in vitro investigation was conducted to evaluate the impact of kaempferol, a natural medication, in an atherosclerotic cell model. We used cytotoxicity assays, Boyden chamber invasion assays, and quantitative PCR. Affymetrix microarrays were used to profile the entire transcriptome of kaempferol-treated cell lines, and Partek Genomic Suite was used to interpret the results. Kaempferol was not cytotoxic to THP-1 macrophages. In comparison to the control, kaempferol reduced monocyte migration mediated by monocyte chemotactic protein 1 (MCP-1) by 80%. The qPCR results showed a 73.7-fold reduction in MCP-1 and a 2.5-fold reduction in intercellular adhesion molecule 1 (ICAM-1) expression in kaempferol-treated cells. In interferon gamma (IFN-γ) without kaempferol and IFN-γ with kaempferol treated cells, we found 295 and 168 differentially expressed genes (DEGs), respectively. According to DEG pathway analysis, kaempferol exhibits anti-atherosclerosis and anti-inflammatory characteristics. Kaempferol is an effective and safe therapy for atherosclerosis.

Sesquiterpene from Polygonum barbatum disrupts mitochondrial membrane potential to induce apoptosis and inhibits metastasis by downregulating matrix metalloproteinase and osteopontin in NCI-H460 cells.

Globally, lung cancer accounts for 18% of cancer-associated mortalities. Among the subtypes, non-small cell lung cancer (NSCLC) is the most prevalent. The increased resistance and poor survival rates signify disease aggressiveness and thus require a search for an alternative anticancer molecule. Earlier, the sesquiterpene, i.e., compound 3 ((E)-methyl 6-acetoxy-7-methoxy-1-(2-methylpropylidene)-1H-indene-3-carboxylate) from Polygonum barbatum, was isolated, characterized by us, and reported for preliminary anticancer activity. Therefore, based on these results, this study was designed to explore the underlying molecular mechanism of apoptosis and metastasis against NCI-H460 cells. The molecular mechanism of compound 3 inducing apoptosis and inhibiting metastasis was elucidated by analyzing mitochondrial membrane potential, DNA fragmentation, clonogenic assay, invasion assay, and expression of apoptotic (caspases 3, 6, 8, 9, and BAK) and metastatic markers (MMP 2, MMP 9, and osteopontin). Compound 3 significantly inhibited cell proliferation and induced apoptosis via the intrinsic route, i.e., the mitochondrial pathway, by disrupting mitochondrial membrane potential. The enhanced expression of caspases 6, 9, BAK, and HRK with downregulation of Bcl-2L1 and Ki67 further confirmed the involvement of the intrinsic apoptotic pathway. Moreover, compound 3 restricted the invasive nature of NCI-H460 cells evinced by reduced cell invasion in Boyden chamber invasion assay and downregulating the expression of metastatic markers, i.e., matrix metalloproteinase 2/9 and VEGF. It was also found to block osteopontin by negatively regulating its expression, a marker protein in cancer management. Conclusively, this sesquiterpene exhibited potent anticancer and antimetastatic activity and can be explored further as possible pharmacophores.

Gambogic acid inhibits epithelial–mesenchymal transition in breast cancer cells through upregulation of SIRT1 expression in vitro

AbstractGambogic acid (GA) is a natural product that selectively induces apoptosis of cancer cells in vitro with high efficiency and low toxicity. Our previous data have shown inhibitory effects of GA on breast cancer cells. However, the detailed mechanisms for GA remain largely unknown. This study aimed to investigate the effect of GA on TGF‐β1‐induced tumor invasion and EMT in MDA‐MB‐231 cells, and contribution of elevated SIRT1 to antitumor effects of GA. Human breast cell MDA‐MB‐231 and MDA‐MB‐231 were incubated with TGF‐β1 (100 ng/ml) and GA. Cell viability was determined by MTT assay, while tumor invasion was determined by Boyden chamber invasion assay. The mRNA levels of SIRT1 and TGF‐β1 were measured by quantitative real‐time polymerase chain reaction (qRT‐PCR). The protein expressions of SIRT1 and EMT‐associated mesenchymal marker Vimentin were measured by Western blotting. Interleukin‐6 (IL‐6) protein content was measured by enzyme linked immunosorbent assays (ELISAs). Our results showed that, GA showed decreased proliferation in MDA‐MB‐231 cells, especially in MDA‐MB‐231 cells with TGF‐β1 incubation. GA inhibited tumor invasion and EMT in TGF‐β1‐treated MDA‐MB‐231 cells. GA increased mRNA and protein expression of SIRT1 in MDA‐MB‐231 cells with and without TGF‐β1 treatment. SIRT1 mRNA level in MDA‐MB‐231 cells was increased by TGF‐β1 incubation and decreased by GA treatment. In addition, the production of IL‐6 was increased by TGF‐β1, and decreased by GA. In conclusion, GA inhibits tumor invasion and EMT in breast cancer, potentially through upregulating SIRT1 expression. This study provides a novel antitumor effect of GA in breast cancer.

Kaempferol inhibits the cell migration of human hepatocellular carcinoma cells by suppressing MMP-9 and Akt signaling.

Metastasis is the most prevalent cause of cancer-related deaths and treatment failure in patients with hepatocellular carcinoma (HCC). Kaempferol is a natural flavonol belonging to the subgroup of flavonoids and exhibits potent anticancer activities. This study provides molecular evidence on the anti-invasive and anti-migratory effects of kaempferol on human HCC cells. The anti-invasive effect was investigated by applying kaempferol on two human HCC cell lines (Huh-7 and SK-Hep-1). Kaempferol reduced the invasion and migration of Huh-7 and SK-Hep-1 cells by Boyden chamber invasion assay and wound healing assay, respectively. A protease array analysis showed that Matrix Metalloproteinase-9 (MMP-9) was dramatically downregulated in HCC cells after kaempferol treatment. Gelatin zymography and Western blot assay showed that kaempferol reduced the activities and protein expression of MMP-9, respectively. Kaempferol also sufficiently suppressed the phosphorylation of the Akt expression. Overall, kaempferol inhibited the invasive properties of human HCC cells by targeting MMP-9 and Akt pathways. Hence, kaempferol could be used as an adjuvant therapeutic agent for the treatment of human HCC cells.

Abstract PS17-15: Targeting the PELP1 axis for treating ESR1 mutant driven breast cancer

Abstract Background: Mutations in ESR1 genes (30-40% frequency) play an important role in acquired endocrine therapy resistance and metastases. The most commonly observed are two ESR1 LBD mutations, D538G andY537S. These mutant ERα (MT) proteins have high constitutive transcriptional activity leading to therapy resistance. Furthermore, the ability of the constitutively active mutants to interact with coregulators is associated with the promotion of tumor growth. Proline, glutamic acid-, and leucine-rich protein 1 (PELP1), an oncogenic coregulator of ERα, plays a critical role in ERα signaling, and its dysregulated expression is a prognostic indicator for poorer breast cancer (BCa) survival. The objective of this study was to test the utility of Small Molecule Inhibitor of PELP1 (SMIP34) for treating ESR1 mutant (MT-ER) driven BCa. Methods: Four BCa models that express either ESR1 mutation D538G or Y537S and their respective wild-typeERα (WT-ER) controls were used to test the utility of targeting the PELP1 axis using PELP1-specific shRNA orSMIP34. Celltiter Glo, MTT, colony formation, and Boyden chamber invasion assays were used to test the efficacy of SMIP34. Western blot, RNA-Seq, and reporter gene assays were utilized to uncover the mechanistic insights. Pre-clinical evaluation was performed using MT-ER expressing xenograft explant (XDEX) and patient-derived explant (PDEX) assays. Results: BCa model cells expressing MT-ER showed increased cell proliferation, whilst PELP1 knock-down significantly reduced their proliferation. Immunoprecipitation results confirmed that PELP1 constitutively associates with MT-ER. PELP1 knock-down or treatment with PELP1 inhibitor SMIP34 significantly reduced proliferation of the four MT-ER models with an IC50 of 3-5μM. PELP1 knock-down or SMIP34 treatment significantly reduced the constitutive ERE reporter activity observed in MT-ER models. RTqPCR assays confirmed the downregulation of MT-ER target genes in PELP1 knock-down and SMIP34 treated cells. Furthermore, PELP1 knock-down or SMIP34 treatment significantly reduced the invasiveness and colony formation of MT-ER BCa models. Mechanistic studies using Western blot revealed that SMIP34 contributes to PELP1 degradation by its direct binding to PELP1. SMIP34 significantly decreased proliferation of MT-ER BCa cells in XDEX andPDEX assays, as measured by Ki67 staining. Conclusion: Our results suggest that PELP1 associates with MT-ER and targeting the PELP1 axis with SMIP34will have therapeutic utility in treating MT-ER driven BCa. Supported by CPRIT Predoctoral Fellowship CPRIT RTA; RP170345 (K.A. Altwegg) and VA grant I01BX004545(R.K.V) Citation Format: Kristin A Altwegg, Suryavathi Viswanadhapalli, Junhao Liu, Zexuan Liu, Uday P. Pratap, Benham Ebrahimi, Hariprasad Vankayalapati, Ratna K. Vadlamudi. Targeting the PELP1 axis for treating ESR1 mutant driven breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS17-15.

Ricinus communis Butanol Fraction Inhibits MCF-7 Breast Cancer Cell Migration, Adhesion, and Invasiveness.

In this study, the potential of an n-butanol fraction from Ricinus communis to prevent metastasis in MCF-7 breast cancer cells was investigated. The effect of the fraction on BUD-8 and MCF-7 cell viability was assessed using the MTT assay. Apoptotic cell death was analyzed by Hoechst staining assay. The antimetastatic effect of the fraction on MCF-7 cell was evaluated using the wound healing, adhesion and Boyden chamber invasion assays. Gelatin-zymography was used to assess the effect of the fraction on MMP-2 and MMP-9 activity. The expression profile of proteins implicated in metastasis and angiogenesis was determined using the human angiogenesis antibody array kit, following treatment with the fraction. BUD-8 cell viability was significantly reduced at concentrations between 300 and 500 µg/ml of the extract. In contrast, a significant reduction in cell viability was seen in MCF-7 cells treated with 400 to 500 µg/ml of the fraction. At sub-lethal concentrations (100 and 200 µg/ml) of the fraction, no nuclei morphological changes associated with apoptotic cell death were observed in MCF-7 cells. In addition, the fraction showed to have an inhibitory effect on MCF-7 cell migration, adhesion, invasiveness, and MMP-2 activity. Moreover, the fraction was seen to modulate the expression of several proteins, such as MMP-9, uPA, VEGF, and TGF-β1, playing a role in the metastasis process. This study demonstrates that the n-butanol fraction of R. communis can inhibit major steps of the metastatic cascade and modulate metastasis regulatory proteins. Thus, the fraction can be considered a potential source of antimetastatic agents that could be useful in the treatment of malignant cancers.

The role of the androgen receptor in prostate cancer‐induced platelet aggregation and platelet‐induced invasion

BackgroundMetastatic prostate cancer progresses from a hormone sensitive androgen receptor expressing phenotype to a hormone insensitive androgen receptor‐independent subtype with low overall survival. Human platelets contribute to metastasis via tumor cell‐induced platelet aggregation, which in part enhances cancer cell invasion. Given the more aggressive nature of hormone insensitive prostate cancer, we hypothesized that androgen receptor‐negative prostate cancer cells exhibit higher platelet aggregation potency and invasive response compared to cells with androgen receptor. ObjectiveTo characterize the role of androgen receptors in prostate cancer‐induced platelet aggregation and platelet‐induced invasion. MethodsTumor cell‐induced platelet aggregation experiments were performed with platelets from healthy human donors and benign prostate (RWPE‐1) and prostate cancer cell lines positive (LNCaP) and negative for androgen receptor (DU145 and PC3). Immunoblot measured prostate cancer prothrombin. Modified Boyden chamber invasion assays and zymography were performed to assess the effects of platelets on prostate cancer cell invasion and matrix metalloproteinase (MMP) expression, respectively. ResultsAndrogen receptor‐positive prostate cancer cell lines failed to induce platelet aggregation. However, androgen receptor‐inhibited and ‐negative cell lines all induced platelet aggregation, which was abolished by dabigatran. Androgen receptor‐inhibited and ‐negative cell lines demonstrated greater expression of prothrombin than androgen receptor‐positive cells. Platelets enhanced invasion and MMP‐2 and ‐9 expression by androgen receptor‐inhibited and negative prostate cancer cells, but not that of the androgen receptor‐positive cells. ConclusionsAndrogen receptor loss within prostate cancer results in increased thrombogenicity due to upregulation of prothrombin expression. Reciprocally, platelets enhance invasion of androgen receptor‐negative prostate cancer cells via increased MMP expression.

Obesity and Breast Cancer: Unraveling the Role of Adipocyte‐Derived Exosomes

Excessive adiposity strongly influences risk, prognosis and progression of breast cancer. The revised concept of adipose tissue from an inert depot for body energy to an endocrine and immunologically active organ placed growing interest on the potential role of adipocyte secreted soluble factors and vesicles, particularly exosomes, as important players in cancer biology. In the last decades, several reports demonstrated that exosomes, small membrane‐derived vesicles, are able to modify target cell phenotype, by transferring bioactive molecules such as proteins, mRNAs, microRNAs, DNAs, lipids and transcriptional factors. However, whether adipose tissue‐derived exosomes, acting as a mode of cell‐to‐cell communication, might have a role in mediating the adverse effects of obesity on breast cancer is still not completely understood.Here, we evaluated the effects of exosomes derived from differentiated 3T3‐L1 adipocytes (3T3‐L1 A), a well recognized ‘in vitro’ model of white adipocytes, on breast cancer phenotype, using as experimental models both estrogen receptor α (ERα)‐positive MCF‐7 and triple negative MDA‐MB‐231 breast cancer cells.Exosomes from 3T3‐L1 A were isolated by sequential ultracentrifugation method, and characterized by Nanoparticle Tracking Analysis, Transmission Electron Microscopy and Immunoblotting analyses. 3T3‐L1 A‐ derived exosome uptake in both breast cancer cell lines was tested by monitoring internalization of exosomes labeled with PKH‐26. Treatment of MCF‐7 and MDA‐MB‐231 breast cancer cells with adipocyte‐derived exosomes did not modify anchorage‐dependent cell growth, while it significantly increased the ability of cells to form colonies in anchorage‐independent soft agar growth assays. In addition, we found that both breast cancer cells treated with adipocyte‐derived exosomes displayed increased migration and invasion capabilities as evidenced by wound healing, and Boyden Chamber migration and invasion assays. Accordingly, adipocyte‐derived exosomes significantly induce the expression of genes involved in Epithelial to Mesenchymal Transition (EMT) in both cell lines. Since migratory potential and EMT represent important features for breast cancer stem cells (BCSCs), we also explored the effect of 3T3L‐1 A‐derived exosomes on MCF‐7 and MDA‐MB‐231 BCSC activity. Interestingly, we found that adipocyte‐derived exosomes were able to increase Mammosphere Forming Efficiency and Self Renewal in breast cancer cells. In conclusion, our data highlight how adipocyte‐derived exosomes may contribute to a more aggressive breast cancer phenotype, providing novel insight in the link between obesity and breast cancer. This may open a new molecular window for preventive and therapeutic strategies to fight breast cancer in obese patients.Support or Funding InformationThis research was funded by Fondazione AIRC: IG #11595 to SA and IG #21414 to SC, and PRIN2017 #2017EKMFTN to SC; PRIN2017 #2017WNKSLR to IB

The inhibition of AGTR1 and Aromatase as a new potential therapeutic strategy for Glioblastoma treatment.

IntroductionGlioblastoma multiforme (GBM) is the most malignant form of glioma causing 3–4% of all cancer‐related deaths. Specific cancer treatment for GBM includes surgery, radiotherapy and chemotherapy with temozolomide. Despite the continuous development of new clinical therapies, the prognosis and survival of GBM patients remain dismal. Thus, the deregulated growth, the migratory and invasive capabilities of glioma cells remain the most important obstacles to the development of effective GBM treatments. Angiotensin II (Ang II)/Ang II receptor 1 (AGTR1) axis is expressed in normal and tumoral tissues, including human GBM. It has been reported in different experimental models that Ang II is able to stimulate aromatase expression through the AGTR1 activation. Different studies have demonstrated that aromatase enzyme is expressed in GBM cells and local estrogen production may act as an autocrine or paracrine factor in enhancing glioblastoma growth and progression. In the present study, we investigated if Ang II/AGTR1 signalling may modulate aromatase expression and consequently local estrogen production, thus influencing glioblastoma survival and growth.MethodsThe Aromatase expression role under treatment with Ang II has been assessed by RT‐PCR, Western blotting, Aromatase activity assay, Transient transfection assays, ELISA assay, cell proliferation assay (Thymidine incorporation), Boyden chamber migration and invasion assays, in the GBM cell line U‐87 MG.ResultsWe identified in U‐87 MG cells that the Ang II up‐regulates the aromatase expression in terms of mRNA, protein levels, and its enzymatic activity. In order to evaluate if Ang II may activate aromatase at transcriptional level we transiently transfected U‐87 MG cells with a vector containing human aromatase promoter I.4, broadly distributed around the brain and widely expressed in glioblastoma cells. Ang II treatment induces an increased aromatase promoter transcriptional activity. Mutagenesis studies and chromatin immunoprecipitation analysis reveal that the integrity of specificity protein 1 (SP1) and interferon‐gamma activation site (GAS) binding sites, within the aromatase promoter is required for Ang II modulation of human aromatase I.4 promoter activity in U87‐MG cells. The enhanced aromatase activity was paralleled by an higher estradiol production concomitant with an increase in cell proliferation, migration and invasion in U‐87 MG cells. These effects are reversed by treatment with an AGTR1 antagonist and/or an aromatase inhibitor, such as Losartan and Anastrozole respectively.ConclusionsAng II/AGTR1 signalling through Aromatase enhances local estrogen production which in turn promotes tumor growth and invasiveness. Therefore, their combined inhibitory targeting may prospectively provide a novel therapeutic strategy for Glioblastoma treatment.

Paeonol Inhibits Pancreatic Cancer Cell Migration and Invasion Through the Inhibition of TGF-β1/Smad Signaling and Epithelial-Mesenchymal-Transition.

PurposePaeonol, a natural product derived from the root of Cynanchum paniculatum (Bunge) K. Schum and the root of Paeonia suffruticosa Andr. (Ranunculaceae) has attracted extensive attention for its anti-cancer proliferation effect in recent years. The present study examined the role of paeonol in suppressing migration and invasion in pancreatic cancer cells by inhibiting TGF-β1/Smad signaling.MethodsCell viability was evaluated by MTT and colonial formation assay. Migration and invasion capabilities were examined by cell scratch-wound healing assay and the Boyden chamber invasion assay. Western Blot and qRT-PCR were used to measure the protein and RNA levels of vimentin, E-cadherin, N-cadherin, and TGF-β1/Smad signaling.ResultsAt non-cytotoxic dose, 100 μΜ and 150 μΜ of paeonol showed significant anti-migration and anti-invasion effects on Panc-1 and Capan-1 cells (p<0.01). Paeonol inhibited epithelial-mesenchymal-transition by upregulating E-cadherin, and down regulating N-cadherin and vimentin expressions. Paeonol inhibited TGF-β1/Smad signaling pathway by downregulating TGF-β1, p-Smad2/Smad2 and p-Smad3/Smad3 expressions. Further, TGF-β1 attenuated the anti-migration and anti-invasion capacities of paeonol in Panc-1 and Capan-1 cells.ConclusionThese findings revealed that paeonol could suppress proliferation and inhibit migration and invasion in Panc-1 and Capan-1 cells by inhibiting the TGF-β1/Smad pathway and might be a promising novel anti-pancreatic cancer drug.

Suppression of LIM Kinase 1 and LIM Kinase 2 Limits Glioblastoma Invasion.

The aggressive brain tumor glioblastoma (GBM) is characterized by rapid cellular infiltration of brain tissue, raising the possibility that disease progression could potentially be slowed by disrupting the machinery of cell migration. The LIM kinase isoforms LIMK1 and LIMK2 (LIMK1/2) play important roles in cell polarization, migration, and invasion and are markedly upregulated in GBM and many other infiltrative cancers. Yet, it remains unclear whether LIMK suppression could serve as a viable basis for combating GBM infiltration. In this study, we investigated effects of LIMK1/2 suppression on GBM invasion by combining GBM culture models, engineered invasion paradigms, and mouse xenograft models. While knockdown of either LIMK1 or LIMK2 only minimally influenced invasion in culture, simultaneous knockdown of both isoforms strongly reduced the invasive motility of continuous culture models and human GBM tumor-initiating cells (TIC) in both Boyden chamber and 3D hyaluronic acid spheroid invasion assays. Furthermore, LIMK1/2 functionally regulated cell invasiveness, in part, by disrupting polarized cell motility under confinement and cell chemotaxis. In an orthotopic xenograft model, TICs stably transduced with LIMK1/2 shRNA were implanted intracranially in immunocompromised mice. Tumors derived from LIMK1/2 knockdown TICs were substantially smaller and showed delayed growth kinetics and more distinct margins than tumors derived from control TICs. Overall, LIMK1/2 suppression increased mean survival time by 30%. These findings indicate that LIMK1/2 strongly regulate GBM invasive motility and tumor progression and support further exploration of LIMK1/2 as druggable targets. SIGNIFICANCE: Targeting the actin-binding proteins LIMK1 and LIMK2 significantly diminishes glioblastoma invasion and spread, suggesting the potential value of these proteins as therapeutic targets.

Nuclear receptor 4A2 (NR4A2) is a druggable target for glioblastomas.

The orphan nuclear receptor 4A2 (NR4A2) has been extensively characterized in subcellular regions of the brain and is necessary for the function of dopaminergic neurons. The NR4A2 ligand, 1,1-bis (31-indoly1)-1-(p-chlorophenyl)methane (DIM-C-pPhCl) inhibits markers of neuroinflammation and degeneration in mouse models and in this study we investigated expression and function of NR4A2 in glioblastoma (GBM). Established and patient-derived cell lines were used as models and the expression and functions of NR4A2 were determined by western blots and NR4A2 gene silencing by antisense oligonucleotides respectively. Effects of NR4A2 knockdown and DIM-C-pPhCl on cell growth, induction of apoptosis (Annexin V Staining) and migration/invasion (Boyden chamber and spheroid invasion assay) and transactivation of NR4A2-regulated reporter genes were determined. Tumor growth was investigated in athymic nude mice bearing U87-MG cells as xenografts. NR4A2 knockdown and DIM-C-pPhCl inhibited GBM cell and tumor growth, induced apoptosis and inhibited migration and invasion of GBM cells. DIM-C-pPhCl and related analogs also inhibited NR4A2-regulated transactivation (luciferase activity) confirming that DIM-C-pPhCl acts as an NR4A2 antagonist and blocks NR4A2-dependent pro-oncogenic responses in GBM. We demonstrate for the first time that NR4A2 is pro-oncogenic in GBM and thus a potential druggable target for patients with tumors expressing this receptor. Moreover, our bis-indole-derived NR4A2 antagonists represent a novel class of anti-cancer agents with potential future clinical applications for treating GBM.

Marine natural compound cyclo(L-leucyl-L-prolyl) peptide inhibits migration of triple negative breast cancer cells by disrupting interaction of CD151 and EGFR signaling

Cyclo (L-Leucyl-L-Prolyl) peptide/CLP is a marine natural metabolite and well recognized as an antimicrobial and antioxidant agent with limited studies on anticancer activity. The current study aims to determine the effect of CLP on migration and growth of triple negative breast cancer cell lines. The anti-growth potential was evaluated by MTT, BrdU and TUNEL assays; DNA damage by γH2AX and Dead green assays; antimigration activity by Boyden chamber invasion and wound healing assays. Interaction of CLP with CD151 was resolved by PatchDock. Effect of CLP on the expression of transmembrane CD151 was evaluated by cell-based ELISA assay. The interaction between CD151 and EGFR was predicted by using FireDoc Web server. Impact of CLP on the interaction of CD151 with EGFR was evaluated by co-immunoprecipitation assay. The effect of CLP on the cell cycle and its controlling proteins was determined by Western blotting. CLP reduced the viability of MDA-MB-231 and MDA-MB-468 TNBC cell lines but not human breast healthy epithelial cell line (MCF-12A) similar to eribulin, standard. CLP also inhibited proliferation; cell cycle and migration. It induced DNA strand breaks, DNA damage, and cell death. It showed the most favorable interactions with CD151 in in silico docking and significantly reduced the expression of membrane-bound CD151 proteins. FireDoc Web study predicted the association between CD151 and EGFR with −29.13 kcal/mol of binding energy. CLP reduced the interaction of CD151 with EGFR along with the expression of cyclin D, CDK4, PAK, RAC1, and P27kiP1.This study concludes that CLP suppresses growth and migration by attenuating cell cycle of TNBC cell lines via EGFR and CD151 signaling. Thus, exploring the EGFR and CD151 signaling pathway targeted by CLP may provide a new approach in the treatment of TNBC.

Dual effects of an anti-CD147 antibody for Esophageal cancer therapy

ABSTRACTBackground: Esophageal cancer is a highly aggressive neoplasm. Targeted therapy has been proven to be a promising way for cancer therapy. Here, we report a novel anti-CD147 antibody for esophageal cancer therapy, which is a chimeric antibody with modified glycoform in Fc region.Methods: ADCC assay was used to explore the antitumor efficacy of Metuzumab against esophageal cancer in vitro. Wound healing assay and Boyden Chamber invasion assay were performed to explore whether Metuzumab could inhibit migration and invasion of esophageal cancer in vitro. Insulin-like growth factors 1 (IGF-1) and PI3k/Akt was assayed for elaborating antagonistic mechanism of Metuzumab in migration and invasion of esophageal cancer cells. Subcutaneous xenograft nude mouse model was used to investigate the antitumor efficacy of Metuzumab against esophageal cancer in vivo. The esophageal cancer tissue microarrays (TMA) was examined for identification of association of CD147 with lymph node metastasis, and the footpad xenograft nude mouse model was used to explore whether Metuzumab could inhibit lymph node metastasis of esophageal cancer in vivo.Results: The results showed that Metuzumab exhibited higher ADCC compared to the wild type antibody cHAb18. Metuzumab inhibited migration and invasion of esophageal cancer through blockade of CD147 in vitro. The results of Western blot showed Metuzumab might inhibit migration and invasion of esophageal cancer cells through suppressing activation of PI3k/Akt and expression of IGF-1. Experiments in vivo showed that Metuzumab exhibited significant antitumor efficacy and inhibited lymph node metastasis of esophageal cancer in xenograft models. The immunochemical staining of TMA showed CD147 was high-expressed on various kinds of esophageal cancer tissues and associated with the grade of lymph node-metastasis.Conclusions: The in vitro and in vivo study demonstrated dual effects of Metuzumab in effectively mediating ADCC by activating effector cells, and inhibiting metastasis of esophageal cancer through blockade the function of CD147, providing justification for moving Metuzumab forward to clinical development in esophageal cancer.

Induction of ALP and MMP9 activity facilitates invasive behavior in heterogeneous human BMSC and HNSCC 3D spheroids.

Mesenchymal stem cells (MSCs) are multipotent progenitor cells capable of differentiating into adipocytic, osteogenic, chondrogenic, and myogenic lineages. There is growing evidence that MSCs home into the tumor microenvironment attracted by a variety of signals such as chemokines, growth factors, and cytokines. Tumor-homing stem cells may originate from bone marrow-derived MSCs (BMSCs) or adipose tissue-derived MSCs. Recent scientific data suggest that MSCs in combination with tumor cells can either promote or inhibit tumorigenic behavior. In head and neck squamous cell carcinoma (HNSCC), BMSCs are reported to be enriched with a potential negative role. Here, we evaluated the effect of BMSCs from 4 different donors in combination with 4 HNSCC cell lines in a 3-dimensional multicellular spheroid model. Heterogeneous combinations revealed an up-regulation of gene and protein expression of osteogenic markers runt-related transcription factor 2 (RUNX2) and alkaline phosphatase (ALP) together with a substantial secretion of matrix metalloproteinase 9. Moreover, heterogenous BMSC/tumor spheroids showed increased invasion compared with homogenous spheroids in a Boyden chamber invasion assay. Furthermore, inhibition of ALP resulted in a substantially decreased spreading of heterogeneous spheroids on laminin-rich matrix. In summary, our data suggest a prometastatic effect of BMSCs combined with HNSCC.-Wessely, A., Waltera, A., Reichert, T. E., Stöckl, S., Grässel, S., Bauer, R. J. Induction of ALP and MMP9 activity facilitates invasive behavior in heterogeneous human BMSC and HNSCC 3D-spheroids.