Cell biology of the movement of breast cancer cells: intracellular signalling and the actin cytoskeleton

Stable overexpression of the epithelial sodium channel alpha subunit reduces migration and proliferation in breast cancer cells

PURPOSE

Breast cancer is the most common cancer diagnosed in women worldwide. Ion channels have emerged as novel regulators of cancer cell functions, including proliferation and migration. The epithelial sodium channel (ENaC) has a key role in blood pressure regulation, and ENaC levels affect the characteristics of several types of cancer. In breast cancer, a role for αENaC has not been investigated in migration previously nor the effect of stable overexpression of αENaC on proliferation.

METHODS

Correlations of the mRNA levels for the four ENaC subunits and breast cancer survival outcomes were assessed in publicly available data and the association between αENaC and migration-related genes. Three isogenic monoclonal derivatives of MDA-MB-231 breast cancer cell lines were created with stable αENaC overexpression. Migration assays (scratch wound assay and Boyden chamber assays) and a proliferation assay (EdU) were used to determine the effect of αENaC overexpression compared to control MDA-MB-231 cells.

RESULTS

Higher α- or δENaC expression was correlated with improved patient survival. Higher αENaC expression correlated with lower expression of migration-associated genes. Stable overexpression of αENaC in MDA-MB-231 cells resulted in reduced in vitro migration and proliferation of all three clones compared to parental control cells.

CONCLUSION

Higher αENaC expression correlates with improved patient outcomes, and overexpression in breast cancer cells reduces both cell migration and proliferation. These results highlight the possibility of ENaC as a target for future breast cancer treatments.

Assessing sarcoma cell cytoskeleton remodeling in response to varying collagen concentration

Sarcomas, rare malignant tumors of mesenchymal origin, are often underdiagnosed and have face diagnostic ambiguities and limited treatment options. The main objective of this study was to define the nanomechanical and biophysical properties of sarcoma cells, particularly examining how the cytoskeleton's remodeling and related cellular processes such as cell migration and invasion in response to environmental stimuli due to collagen content. Utilizing one murine fibrosarcoma and one osteosarcoma cell line we employed atomic force microscopy, immunostaining, advanced image processing, in vitro cellular assays, and molecular techniques to investigate cells' cytoskeleton remodeling in response to varying collagen concentration. Our study focused on how alterations in collagen content affects the cytoskeletal dynamics and correlate with changes in gene expression profiles relevant to metastasis and an aggressive cancer phenotypes. Our findings indicate that despite their shared classification, fibrosarcoma and osteosarcoma cells display distinct biophysical properties and respond differently to mechanical forces. Notably, this difference in cellular behavior renders mechanical properties a potent novel biomarkers. Furthermore, the metastasis-related identified genes related to metastatic capability, could be potential therapeutic targets. This study highlights the significance of understanding the unique traits of sarcoma cells to improve diagnostic precision and expand therapeutic strategies, for this rare type of cancer.

Upregulation of CALD1 predicted a poor prognosis for platinum-treated ovarian cancer and revealed it as a potential therapeutic resistance target

BACKGROUND

Ovarian cancer (OC) has the worst prognosis among gynecological malignancies, most of which are found to be in advanced stage. Cell reduction surgery based on platinum-based chemotherapy is the current standard of treatment for OC, but patients are prone to relapse and develop drug resistance. The objective of this study was to identify a specific molecular target responsible for platinum chemotherapy resistance in OC.

RESULTS

We screened the protein-coding gene Caldesmon (CALD1), expressed in cisplatin-resistant OC cells in vitro. The prognostic value of CALD1 was evaluated using survival curve analysis in OC patients treated with platinum therapy. The diagnostic value of CALD1 was verified by drawing a Receiver Operating Characteristic (ROC) curve using clinical samples from OC patients. This study analyzed data from various databases including Gene Expression Omnibus (GEO), Human Protein Atlas (HPA), The Cancer Cell Line Encyclopedia (CCLE), The Cancer Genome Atlas (TCGA), GEPIA 2, UALCAN, Kaplan-Meier (KM) plotter, LinkedOmics database, and String. Different expression genes (DEGs) between cisplatin-sensitive and cisplatin-resistant cells were acquired respectively from 5 different datasets of GEO. CALD1 was selected as a common gene from 5 groups DEGs. Online data analysis of HPA and CCLE showed that CALD1 was highly expressed in both normal ovarian tissue and OC. In TCGA database, high expression of CALD1 was associated with disease stage and venous invasion in OC. Patients with high CALD1 expression levels had a worse prognosis under platinum drug intervention, according to Kaplan-Meier (KM) plotter analysis. Analysis of clinical sample data from GEO showed that CALD1 had superior diagnostic value in distinguishing patients with platinum "resistant" and platinum "sensitive" (AUC = 0.816), as well as patients with worse progression-free survival (AUC = 0.741), and those with primary and omental metastases (AUC = 0.811) in ovarian tumor. At last, CYR61 was identified as a potential predictive molecule that may play an important role alongside CALD1 in the development of platinum resistance in OC.

CONCLUSIONS

CALD1, as a member of cytoskeletal protein, was associated with poor prognosis of platinum resistance in OC, and could be used as a target protein for mechanism study of platinum resistance in OC.

Dexamethasone targets actin cytoskeleton signaling and inflammatory mediators to reverse sulfur mustard-induced toxicity in rabbit corneas

PURPOSE

Sulfur mustard (SM), a bi-functional alkylating agent, was used during World War I and the Iran-Iraq war. SM toxicity is ten times higher in eyes than in other tissues. Cornea is exceptionally susceptible to SM-injuries due to its anterior positioning and mucous-aqueous interphase. Ocular SM exposure induces blepharitis, photosensitivity, dry eye, epithelial defects, limbal ischemia and stem cell deficiency, and mustard gas keratopathy leading to temporary or permanent vision impairments. We demonstrated that dexamethasone (Dex) is a potent therapeutic intervention against SM-induced corneal injuries; however, its mechanism of action is not well known. Investigations employing proteomic profiling (LC-MS/MS) to understand molecular mechanisms behind SM-induced corneal injury and Dex efficacy were performed in the rabbit cornea exposed to SM and then received Dex treatment. PEAKS studio was used to extract, search, and summarize peptide identity. Ingenuity Pathway Analysis was used for pathway identification. Validation was performed using immunofluorescence. One-Way ANOVA (FDR < 0.05; p < 0.005) and Student's t-test (p < 0.05) were utilized for analyzing proteomics and IF data, respectively. Proteomic analysis revealed that SM-exposure upregulated tissue repair pathways, particularly actin cytoskeleton signaling and inflammation. Prominently dysregulated proteins included lipocalin2, coronin1A, actin-related protein2, actin-related protein2/3 complex subunit2, actin-related protein2/3 complex subunit4, cell division cycle42, ezrin, bradykinin/kininogen1, moesin, and profilin. Upregulated actin cytoskeleton signaling increases F-actin formation, dysregulating cell shape and motility. Dex reversed SM-induced increases in the aforementioned proteins levels to near control expression profiles. Dex aids corneal wound healing and improves corneal integrity via actin cytoskeletal signaling and anti-inflammatory effects following SM-induced injuries.

Mechanism of synergistic inhibitory effect of benzyl isothiocyanate and zoledronic acid combination on breast cancer induction of osteoclast differentiation

Bone is the most favored site for metastasis for each major subtype of breast cancer. Therapeutic modalities for alleviation of clinical symptoms associated with bone metastasis include surgical resection, radiation, and bone-targeted therapies, including bisphosphonates (e.g., zoledronic acid; ZA) and a humanized antibody against receptor activator of nuclear factor-κB ligand (denosumab). However, the bone-targeted therapies are expensive, and have poor pharmacokinetic attributes and/or serious adverse effects. Therefore, novel strategies are needed for treatment of bone metastasis or to increase effectiveness of existing bone-targeted therapies. We have shown previously that benzyl isothiocyanate (BITC) is a novel inhibitor of osteoclast differentiation in vitro and bone metastasis in vivo. The present study shows that BITC + ZA combination synergistically inhibits osteoclast differentiation induced by addition of conditioned media from breast cancer cells. These effects were associated with a significant increase in levels of several antiosteoclastogenic cytokines, including interferons, interleukin (IL)-3, IL-4, and IL-27. Kyoto Encyclopedia of Genes and Genomes pathway analysis of RNA-seq data from BITC and/or ZA-treated cells revealed downregulation of genes of many pathways (e.g., actin cytoskeleton, Hippo signaling, etc.) by treatment with BITC + ZA combination, but not by BITC alone or ZA alone. Confocal microscopy confirmed severe disruption of actin cytoskeleton upon treatment of MCF-7 and MDA-MB-231 cells with the BITC + ZA combination. This combination also decreased the nuclear level of yes-associated protein, a core component of Hippo signaling. In conclusion, the present study offers a novel combination for prevention or treatment of bone metastasis of breast cancer.

Remodeled tumor immune microenvironment (TIME) parade via natural killer cells reprogramming in breast cancer

Breast cancer (BC) is the main cause of cancer-related mortality among women globally. Despite substantial advances in the identification and management of primary tumors, traditional therapies including surgery, chemotherapy, and radiation cannot completely eliminate the danger of relapse and metastatic illness. Metastasis is controlled by microenvironmental and systemic mechanisms, including immunosurveillance. This led to the evolvement of immunotherapies that has gained much attention in the recent years for cancer treatment directed to the innate immune system. The long forgotten innate immune cells known as natural killer (NK) cells have emerged as novel targets for more effective therapeutics for BC. Normally, NK cells has the capacity to identify and eradicate tumor cells either directly or by releasing cytotoxic granules, chemokines and proinflammatory cytokines. Yet, NK cells are exposed to inhibitory signals by cancer cells, which causes them to become dysfunctional in the immunosuppressive tumor microenvironment (TME) in BC, supporting tumor escape and spread. Potential mechanisms of NK cell dysfunction in BC metastasis have been recently identified. Understanding these immunologic pathways driving BC metastasis will lead to improvements in the current immunotherapeutic strategies. In the current review, we highlight how BC evades immunosurveillance by rendering NK cells dysfunctional and we shed the light on novel NK cell- directed therapies.

Chorein sensitive microtubule organization in tumor cells

Background

The purpose of this study is to analyzed the involvement of chorein in microtubules organization of three types of malignant; rhabdomyosarcoma tumor cells (ZF), rhabdomyosarcoma cells (RH30), and rhabdomyosarcoma cells (RD). ZF are expressing high chorein levels. Previous studies revealed that chorein protein silencing in ZF tumor cells persuaded apoptotic response followed by cell death. In addition, in numerous malignant and non-malignant cells this protein regulates actin cytoskeleton structure and cellular signaling. However, the function of chorein protein in microtubular organization is yet to be established.

Methods

In a current research study, we analyzed the involvement of chorein in microtubules organization by using three types of malignant rhabdomyosarcoma cells. We have applied confocal laser-scanning microscopy to analyze microtubules structure and RT-PCR to examine cytoskeletal gene transcription.

Results

We report here that in rhabdomyosarcoma cells (RH30), chorein silencing induced disarrangement of microtubular network. This was documented by laser scanning microscopy and further quantified by FACS analysis. Interestingly and in agreement with previous reports, tubulin gene transcription in RH cells was unchanged upon silencing of chorein protein. Equally, confocal analysis showed minor disordered microtubules organization with evidently weakened staining in rhabdomyosarcoma cells (RD and ZF) after silencing of chorein protein.

Conclusion

These results disclose that chorein silencing induces considerable structural disorganization of tubulin network in RH30 human rhabdomyosarcoma tumor cells. Additional studies are now needed to establish the role of chorein in regulating cytoskeleton architecture in tumor cells.

Molecular characterization of breast cancer cell pools with normal or reduced ability to respond to progesterone: a study based on RNA-seq

BACKGROUND

About one-third of patients with estrogen receptor alpha (ERα)-positive breast cancer have tumors which are progesterone receptor (PR) negative. PR is an important prognostic factor in breast cancer. Patients with ERα-positive/PR-negative tumors have shorter disease-free and overall survival than patients with ERα-positive/PR-positive tumors. New evidence has shown that progesterone (P4) has an anti-proliferative effect in ERα-positive breast cancer cells. However, the role of PR in breast cancer is only poorly understood.

METHODS

We disrupted the PR gene (PGR) in ERα-positive/PR-positive T-47D cells using the CRISPR/Cas9 system. This resulted in cell pools we termed PR-low as P4 mediated effects were inhibited or blocked compared to control T-47D cells. We analyzed the gene expression profiles of PR-low and control T-47D cells in the absence of hormone and upon treatment with P4 alone or P4 together with estradiol (E2). Differentially expressed (DE) genes between experimental groups were characterized based on RNA-seq and Gene Ontology (GO) enrichment analyses.

RESULTS

The overall gene expression pattern was very similar between untreated PR-low and untreated control T-47D cells. More than 6000 genes were DE in control T-47D cells upon stimulation with P4 or P4 plus E2. When PR-low pools were subjected to the same hormonal treatment, up- or downregulation was either blocked/absent or consistently lower. We identified more than 3000 genes that were DE between hormone-treated PR-low and control T-47D cells. GO analysis revealed seven significantly enriched biological processes affected by PR and associated with G protein-coupled receptor (GPCR) pathways which have been described to support growth, invasiveness, and metastasis in breast cancer cells.

CONCLUSIONS

The present study provides new insights into the complex role of PR in ERα-positive/PR-positive breast cancer cells. Many of the genes affected by PR are part of central biological processes of tumorigenesis.

Integrated molecular modeling and dynamics approaches revealed potential natural inhibitors of NF-κB transcription factor as breast cancer therapeutics

Breast cancer is a silent killer malady among women and a serious economic burden in health care management. A case of breast cancer is diagnosed among women every 19 s, and every 74 s, a woman dies of breast cancer somewhere in the world. Despite the pop-up of progressive research, advanced treatment approaches, and preventive measures, breast cancer remains amplifying ailment. The nuclear factor kappa B (NF-κB) is a key transcription factor that links inflammation with cancer and is demonstrated as being involved in the tumorigenesis of breast cancer. The NF-κB transcription factor family in mammals consists of five proteins; c-Rel, RelA(p65), RelB, NF-κB1(p50), and NF-κB2(p52). The antitumor effect of NF-κB has also been explored in breast cancer, however, the actual treatment for breast cancer is yet to be discovered. This study is attributed to the identification of novel drug targets against breast cancer by targeting c-Rel, RelA(p65), RelB, NF-κB1(p50), and NF-κB2(p52) proteins. To identify the putative active compounds, a structure-based 3D pharmacophore model to the protein active site cavity was generated followed by virtual screening, molecular docking, and molecular dynamics (MD) simulation. Initially, a library of 45000 compounds were docked against the target protein and five compounds namely Z56811101, Z653426226, Z1097341967, Z92743432, and Z464101066 were selected for further analysis. The relative binding affinity of Z56811101, Z653426226, Z1097341967, Z92743432, and Z464101066 with NF-κB1 (p50), NF-κB2 (p52), RelA (p65), RelB, and c-Rel proteins were -6.8, -8, -7.0, -6.9, and -7.2 kcal/mol, respectively which remained stable throughout the simulations of 200 ns. Furthermore, all of these compounds depict maximum drug-like properties. Therefore, the proposed compounds can be a potential candidate for patients with breast cancer, but, experimental validation is needed to ensure their safety.Communicated by Ramaswamy H. Sarma.

Screening ANLN and ASPM as bladder urothelial carcinoma-related biomarkers based on weighted gene co-expression network analysis

Introduction: Bladder cancer (BLCA) is one of the most common malignancies in the urinary system with a poor prognosis and high treatment costs. Identifying potential prognostic biomarkers is significant for exploring new therapeutic and predictive targets of BLCA.

Methods: In this study, we screened differentially expressed genes using the GSE37815 dataset. We then performed a weighted gene co‐expression network analysis (WGCNA) to identify the genes correlated with the histologic grade and T stage of BLCA using the GSE32548 dataset. Subsequently, Kaplan Meier survival analysis and Cox regression were used to further identify prognosis‐related hub genes using the datasets GSE13507 and TCGA‐BLCA. Moreover, we detected the expression of the hub genes in 35 paired samples, including BLCA and paracancerous tissue, from the Shantou Central Hospital by qRT‐polymerase chain reaction.

Results: This study showed that Anillin (ANLN) and Abnormal spindle-like microcephaly-associated gene (ASPM) were prognostic biomarkers for BLCA. High expression of ANLN and ASPM was associated with poor overall survival.The qRT‐PCR results revealed that ANLN and ASPM genes were upregulated in BLCA, and there was a correlation between the expression of ANLN and ASPM in cancer tissues and paracancerous tissue. Additionally, the increasing multiples in the ANLN gene was obvious in high-grade BLCA.

Discussion: In summary, this preliminary exploration indicated a correlation between ANLN and ASPM expression. These two genes, serving as the risk factors for BLCA progression, might be promising targets to improve the occurrence and progression of BLCA.

CircSTK3 drives the metastasis of colorectal cancer by regulating epithelial-mesenchymal transition

Circular RNAs (circRNAs) play crucial roles in malignancies. We aimed to delineate the functions and clinical importance of dysregulated circRNAs in colorectal cancer (CRC). We determined the circRNA expression profile from five CRC and paired adjacent normal tissues using circRNA microarray. We found that a novel circRNA, hsa_circ_0004592 (named circSTK3), was significantly upregulated in CRC tissues and correlated with decreased survival. Loss- and gain-of-function assays revealed that circSTK3 promoted the migration and invasion but not proliferation of cells. Whole genome expression microarray identified potential downstream targets and the regulatory networks of circSTK3; Gene Ontology analysis confirmed circSTK3 involvement in the CRC metastasis phenotype. Abnormal circSTK3 expression affected a subset of genes associated with CRC metastasis and triggered epithelial-mesenchymal transition programming, maintaining a tumor-promoting signature. Moreover, circSTK3 was transcriptionally regulated by CTCF. These findings reveal the functional and prognostic roles of circSTK3 and expose circRNAs as key players in metastasis.

Sodium alginate-based drug delivery for diabetes management: A review

Diabetes mellitus (DM) is among the biggest global health problems of the 21st century, which is characterised by insufficient insulin secretion and results in the augmentation of blood sugar levels. The current foundation of hyperglycemia therapy is oral antihyperglycemic medications like biguanides, sulphonylureas, α-glucosidase inhibitors, peroxisome proliferator-activated receptor gamma (PPAR-γ) agonists, sodium-glucose co-transporter 2 (SGLT-2) inhibitors, dipeptidyl peptidase-4 (DPP-4) inhibitors and others. Many naturally occurring substances have shown promise in treating hyperglycemia. Inadequate prologitivity of action, restricted bioavailability, site specificity, and dose-related side effects are some problems with currently available anti-diabetic medications. Sodium alginate has shown promise as a drug delivery mechanism, potentially solving issues with current therapies for several substances. This review summarizes the research on the efficacy of drug delivery systems based on alginate for transporting oral hypoglycemic medicines, phytochemicals, and insulin for treating hyperglycemia.

MicroRNA-206 in human cancer: Mechanistic and clinical perspectives

MicroRNAs (miRNAs), small non-coding RNAs approximately 20-25 nt in length, play important roles via directly binding to the corresponding 3' UTR of target mRNAs. Recent research has shown that miRNAs cover a wide range of diseases, including several types of cancer. It is interesting to note that miR-206 operates as a tumor suppressor and is downregulated in abundant cancer types, such as breast cancer, lung cancer, colorectal cancer, and so forth. Interestingly, a growing number of studies have also reported that miR-206 could function as an oncogene and promote tumor cell proliferation. Thereby, miR-206 may act as either oncogenes or tumor suppressors under certain conditions. In addition, it was widely acknowledged that restoring tumor-suppressor miR-206 has emerged as an unconventional cancer therapy strategy. Therefore, miR-206 might be a newfangled procedure for achieving a more significant treatment outcome for cancer patients. This review summarizes the role of miR-206 in several cancer types and the contributions made between miR-206 and the diagnosis, treatment, and drug resistance of solid tumors.

Copper-Dependent Kinases and Their Role in Cancer Inception, Progression and Metastasis

In recent years, copper function has been expanded beyond its consolidated role as a cofactor of enzyme catalysis. Recent papers have demonstrated a new dynamic role for copper in the regulation of cell signaling pathways through direct interaction with protein kinases, modulating their activity. The activation of these pathways is exacerbated in cancer cells to sustain the different steps of tumor growth and dissemination. This review will focus on a novel proposed role for the transition metal copper as a regulator of cell signaling pathways through direct interaction with known protein kinases, which exhibit binding domains for this metal. Activation of these pathways in cancer cells supports both tumor growth and dissemination. In addition to the description of the results recently reported in the literature on the subject, relevance will be given to the possibility of controlling the cellular levels of copper and its homeostatic regulators. Overall, these findings may be of central relevance in order to propose copper and its homeostatic regulators as possible targets for novel therapies, which may act synergistically to those already existing to control cancer growth and dissemination.

Deciphering the role of predicted miRNAs of polyomaviruses in carcinogenesis

Human polyomaviruses are relatively common in the general population. Polyomaviruses maintain a persistent infection after initial infection in childhood, acting as an opportunistic pathogen in immunocompromised populations and their association has been linked to carcinogenesis. A comprehensive understanding of the underlying molecular mechanisms of carcinogenesis in consequence of polyomavirus infection remains elusive. However, the critical role of viral miRNAs and their potential targets in modifying the transcriptome profile of the host remains largely unknown. Polyomavirus-derived miRNAs have the potential to play a substantial role in carcinogenesis. Employing computational approaches, putative viral miRNAs along with their target genes have been predicted and possible roles of the targeted genes in many significant biological processes have been obtained. Polyomaviruses have been observed to target intracellular signal transduction pathways through miRNA-mediated epigenetic regulation, which may contribute to cancer development. In addition, BKPyV-infected human renal cell microarray data was coupled with predicted target genes and analysis of the downregulated genes indicated that viruses target multiple signaling pathways (e.g. MAPK signaling pathway, PI3K-Akt signaling pathway, PPAR signaling pathway) in the host as well as turning off several tumor suppression genes (e.g. FGGY, EPHX2, CACNA2D3, CDH16) through miRNA-induced mechanisms, assuring cell transformation. This study provides a conceptual framework for the underlying molecular mechanisms involved in the course of carcinogenesis upon polyomavirus infection.

Proteomic Analysis of HCC-1954 and MCF-7 Cell Lines Highlights Crosstalk between αv and β1 Integrins, E-Cadherin and HER-2

Overexpression of human epidermal growth factor receptor-2 (HER-2) occurs in 20% of all breast cancer subtypes, especially those that present the worst prognostic outcome through a very invasive and aggressive tumour. HCC-1954 (HER-2+) is a highly invasive, metastatic cell line, whereas MCF-7 is mildly aggressive and non-invasive. We investigated membrane proteins from both cell lines that could have a pivotal biological significance in metastasis. Membrane protein enrichment for HCC-1954 and MCF-7 proteomic analysis was performed. The samples were analysed and quantified by mass spectrometry. High abundance membrane proteins were confirmed by Western blot, immunofluorescence, and flow cytometry. Protein interaction prediction and correlations with the Cancer Genome Atlas (TCGA) patient data were conducted by bioinformatic analysis. In addition, β1 integrin expression was analysed by Western blot in cells upon trastuzumab treatment. The comparison between HCC-1954 and MCF-7 membrane-enriched proteins revealed that proteins involved in cytoskeleton organisation, such as HER-2, αv and β1 integrins, E-cadherin, and CD166 were more abundant in HCC-1954. β1 integrin membrane expression was higher in the HCC-1954 cell line resistant after trastuzumab treatment. TCGA data analysis showed a trend toward a positive correlation between HER-2 and β1 integrin in HER-2+ breast cancer patients. Differences in protein profile and abundance reflected distinctive capabilities for aggressiveness and invasiveness between HCC-1954 and MCF-7 cell line phenotypes. The higher membrane β1 integrin expression after trastuzumab treatment in the HCC-1954 cell line emphasised the need for investigating the contribution of β1 integrin modulation and its effect on the mechanism of trastuzumab resistance.

Diltiazem inhibits breast cancer metastasis via mediating growth differentiation factor 15 and epithelial-mesenchymal transition

Migration and metastasis commonly happen to triple-negative breast cancer (TNBC) patients with advanced diseases. In many studies, it has been suggested that epithelial-mesenchymal transition (EMT) is one of the key mechanisms triggering cancer metastasis. Accumulating evidence has proven that calcium channel blockers mediate cell motility. Therefore, we attempt to investigate the effects of diltiazem, which has been selected from several FDA-approved clinical calcium channel blockers, on EMT in TNBC. By using both mouse and human TNBC cell lines, we found that diltiazem decreases colony formation and cell migration in breast cancer cells. The expression of epithelial markers such as E-cadherin and ZO-1 were increased dose-dependently by diltiazem, while mesenchymal markers such as Snail and Twist were decreased. In addition, we found that the expression of growth differentiation factor-15 (GDF-15) was also increased by diltiazem. Administering recombinant GDF-15 also reverses EMT, inhibits colony formation and migration in breast cancer cells. Moreover, treatment with diltiazem in tumor-bearing mice also decreases cancer metastasis and nodule formation, with more GDF-15 expression in diltiazem-treated mice than saline-treated mice, respectively. These findings suggest that diltiazem regulates EMT and cell motility through elevating GDF-15 expression in breast cancers in vitro and in vivo.

Breast Cancer Selective Disruption of Actin Cytoskeleton by Diallyl Trisulfide

Diallyl trisulfide (DATS) is an attractive anti-cancer phytochemical with in vitro and in vivo growth inhibitory effects against different solid tumors including breast cancer. We have shown previously that an immortalized mammary epithelial cell line (MCF-10A) is resistant to growth inhibition by DATS. In this study, we performed RNA-seq analysis using a breast cancer cell line (SK-BR-3) and MCF-10A cells to gain insights into cancer selective effects of DATS. The Gene Ontology analysis revealed upregulation of genes associated with actin cytoskeleton but downregulation of mitochondria-related genes in the SK-BR-3 human breast cancer cell line but not in the non-oncogenic MCF-10A cell line upon treatment with DATS. Quantitative real-time reverse transcription polymerase chain reaction confirmed DATS-mediated upregulation of several actin cytoskeleton-related genes in the SK-BR-3 cell line. The DATS treatment dose-dependently disrupted actin cytoskeleton in the SK-BR-3 cell line, whereas the MCF-10A cell line was more resistant to this effect. The DATS treatment caused a marked increase in phosphorylation of dynamin-1-like (DRP1) protein in the SK-BR-3 cell line. However, the DATS-mediated apoptosis was not affected by genetic deletion of DRP1 protein. The Reactome pathway analysis showed downregulation of genes associated with citric acid cycle in the SK-BR-3 cell line but not in the MCF-10A cells. However, expression of aconitase 2 or dihydrolipoamide S-succinyltransferase was not affected by DATS treatment. In conclusion, this study reveals that actin cytoskeleton is a novel target of DATS in the SK-BR-3 cell line, which may explain its inhibitory effect on breast cancer cell migration.

A Resveratrol Phenylacetamide Derivative Perturbs the Cytoskeleton Dynamics Interfering with the Migration Potential in Breast Cancer

Chemotherapy is commonly used for cancer treatment, however the lack of selectivity on healthy cells and the development of resistance phenomena are the major issues. A better understanding of cancer genetics helped the development of new targeted anticancer treatments, which permit drug delivery with high specificity and lower toxicity. Moreover, the multi-target drug design concept represents the current trend for future drug research and development. Starting from good results previously obtained by our research group on the resveratrol (RSV) phenylacetamide derivative 2, which displayed an interesting anti-inflammatory and anti-proliferative activity towards the breast cancer cells MCF-7 and MDA-MB-231, we identified other features, as the ability to perturb the cytoskeleton dynamics and interfere with the migration and metastatic processes. In vitro and in silico studies demonstrate that the derivative 2 is a tubulin and actin polymerization inhibitor and an actin depolymerization promotor. In addition, it interferes with the metastatic potential in both the breast cancer cells, inhibiting the in vitro cell migration and decreasing the spheroids number. These promising results demonstrate that the RSV phenylacetamide derivative 2 could be an important starting point in the discovery and development of safer and more efficacy multi-targeted agents.

The antimetastatic breast cancer activity of the viral protein-derived peptide vCPP2319 as revealed by cellular biomechanics

The incidence of metastatic breast cancer (MBC) is increasing and the therapeutic arsenal available to fight it is insufficient. Brain metastases, in particular, represent a major challenge for chemotherapy as the impermeable nature of the blood-brain barrier (BBB) prevents most drugs from targeting cells in the brain. For their ability to transpose biological membranes and transport a broad spectrum of bioactive cargoes, cell-penetrating peptides (CPPs) have been hailed as ideal candidates to deliver drugs across biological barriers. A more ambitious approach is to have the CPP as a drug itself, capable of both killing cancer cells and interacting with the blood/brain interface, therefore blocking the onset of brain metastases. vCPP2319, a viral protein-derived CPP, has both properties as it: (a) is selective toward human breast cancer cells (MDA-MB-231) and increases cell stiffness compared to breast epithelial cells (MCF 10A) hindering the progression of metastases; and (b) adsorbs at the surface of human brain endothelial cells potentially counteracting metastatic cells from reaching the brain. Overall, the results reveal the selective anticancer activity of the peptide vCPP2319, which is also able to reside at the blood-brain interface, therefore counteracting brain penetration by metastatic cancer cells.

A novel role of ADGRF1 (GPR110) in promoting cellular quiescence and chemoresistance in human epidermal growth factor receptor 2-positive breast cancer

While G protein-coupled receptors (GPCRs) are known to be excellent drug targets, the second largest family of adhesion-GPCRs is less explored for their role in health and disease. ADGRF1 (GPR110) is an adhesion-GPCR and has an important function in neurodevelopment and cancer. Despite serving as a poor predictor of survival, ADGRF1's coupling to G proteins and downstream pathways remain unknown in cancer. We evaluated the effects of ADGRF1 overexpression on tumorigenesis and signaling pathways using two human epidermal growth factor receptor-2-positive (HER2+) breast cancer (BC) cell-line models. We also interrogated publicly available clinical datasets to determine the expression of ADGRF1 in various BC subtypes and its impact on BC-specific survival (BCSS) and overall survival (OS) in patients. ADGRF1 overexpression in HER2+ BC cells increased secondary mammosphere formation, soft agar colony formation, and % of Aldefluor-positive tumorigenic population in vitro and promoted tumor growth in vivo. ADGRF1 co-immunoprecipitated with both Gαs and Gαq proteins and increased cAMP and IP1 when overexpressed. However, inhibition of only the Gαs pathway by SQ22536 reversed the pro-tumorigenic effects of ADGRF1 overexpression. RNA-sequencing and RPPA analysis revealed inhibition of cell cycle pathways with ADGRF1 overexpression, suggesting cellular quiescence, as also evidenced by cell cycle arrest at the G0/1 phase and resistance to chemotherapy in HER2+ BC. ADGRF1 was significantly overexpressed in the HER2-enriched BC compared to luminal A and B subtypes and predicted worse BCSS and OS in these patients. Therefore, ADGRF1 represents a novel drug target in HER2+ BC, warranting discovery of novel ADGRF1 antagonists.

Role of Src/FAK in migration and invasion mediated by extracellular vesicles from MDA-MB-231 cells stimulated with linoleic acid

Linoleic acid (LA) is the most abundant polyunsaturated fatty acid in occidental diets, which mediate a variety of processes in human breast cancer cells, including migration and invasion. Extracellular vesicles (EVs) are vesicles released from endosomes and plasma membrane that are composed of a variety of molecules, including proteins, nucleic acids and lipids. EVs from cancer cells promote processes related with cancer progression. In the present study, we demonstrate that treatment of MDA-MB-231 cells with EVs from MDA-MB-231 cells stimulated with LA (LA EVs) promote migration and invasion via Src activity. LA EVs induce activation of FAK via Src activity and of Src and Akt2. LA EVs also induce the assembly of focal adhesions and MMP-9 secretion. These findings demonstrate that LA EVs mediate an autocrine and/or paracrine Src/FAK signaling pathway to promote migration and invasion.

Anillin is an emerging regulator of tumorigenesis, acting as a cortical cytoskeletal scaffold and a nuclear modulator of cancer cell differentiation

Remodeling of the intracellular cytoskeleton plays a key role in accelerating tumor growth and metastasis. Targeting different cytoskeletal elements is important for existing and future anticancer therapies. Anillin is a unique scaffolding protein that interacts with major cytoskeletal structures, e.g., actin filaments, microtubules and septin polymers. A well-studied function of this scaffolding protein is the regulation of cytokinesis at the completion of cell division. Emerging evidence suggest that anillin has other important activities in non-dividing cells, including control of intercellular adhesions and cell motility. Anillin is markedly overexpressed in different solid cancers and its high expression is commonly associated with poor prognosis of patient survival. This review article summarizes rapidly accumulating evidence that implicates anillin in the regulation of tumor growth and metastasis. We focus on molecular and cellular mechanisms of anillin-dependent tumorigenesis that include both canonical control of cytokinesis and novel poorly understood functions as a nuclear regulator of the transcriptional reprogramming and phenotypic plasticity of cancer cells.

Multiwalled carbon nanotubes inhibit cell migration and invasion by destroying actin cytoskeleton via mitochondrial dysfunction in ovarian cancer cells

Objective: This study aimed to investigate the effects of multiwalled carbon nanotubes (MWCNTs) on cytotoxicity and tumor metastasis in ovarian cancer cells, and further explored its mechanism.

Results: MWCNTs significantly inhibited cell viability and the clone number, increased the cell number of S phage, promoted cell apoptosis, as well as suppressed cell migration and invasion, and damaged the structure of actin cytoskeleton in a dose-dependent manner in SKOV3. Moreover, MWCNTs treatment obviously damaged the structure of actin cytoskeleton of SKOV3, and inhibited the activities of mitochondrial electron transfer chain complexes I-V.

Conclusions: MWCNTs might influence the assembly of actin cytoskeleton by disrupting mitochondrial function, thereby inhibiting migration and invasion of SKOV3.

Methods: The characterization of MWCNTs was analyzed by UV visible light absorption spectroscopy and transmission electron microscopy. SKOV3 cells were exposed to different doses of MWCNTs. Then, in vitro cytotoxicity of MWCNTs was evaluated by MTT assay, colony-forming assay, cell cycle, and cell apoptosis assay. Moreover, the effects of MWCNTs on cell migration and invasion as well as actin cytoskeleton were explored in SKOV3 cells. Furthermore, the mitochondrial membrane potential and the activities of mitochondrial electron transfer chain complexes I-V were measured.

Anti-metastatic action of an N 4-aryl substituted thiosemicarbazone on advanced triple negative breast cancer

Purpose

Advanced triple negative breast cancer (ATNBC) is defined by a lack of expression of hormones receptors as well as HER2/neu and its high probability of visceral metastasis. This pathology is associated with a poor prognosis. Previously, we found that T2, an N⁴-arylsubstituted thiosemicarbazone (N⁴-TSC), had cytotoxic effect on human breast cancer cells lines. Hence, in this study, we investigated the anti-metastasic action of T2 on ATNBC.

Methods

In order to deepen T2 action mode on ATNBC, we first confirmed T2 cytotoxicity on a panel of TNBC cells and then continued studying T2 effects in vitro an in vivo on the syngeneic 4T1 mouse model.

Results

We found that T2 had a cytotoxic effect comparable to chemotherapeutics used in present treatment schemes for ATNBC. T2 treatment not only induced apoptosis, but it also down-modulated 4T1 invasive and metastatic-associated capacities, such as clonogenicity, migration and metallo-proteases activity. Moreover, this agent reduced the number of 4T1 cancer stem cells. Finally, T2 treatment induced a more differentiated cell phenotype and the overexpression of the metastasis suppressor gene NDRG-1. In vivo assays showed that T2 reduced tumor burden, down modulated local tumor invasion and significantly reduced the number of lung metastases in the 4T1 advanced TNBC murine model, while the compound did not exhibit intolerable toxicity.

Conclusion

This study provided evidence that T2 not only exerted an anti-tumor activity but it also showed anti-invasive and anti-metastatic actions on ATNBC in vivo and in vitro, suggesting that T2 could be considered as a promising therapy that deserves further analysis.

Graphene oxide inhibits cell migration and invasion by destroying actin cytoskeleton in cervical cancer cells

OBJECTIVE

To investigate the antitumor effects of Graphene oxide (GO) on tumor invasion and metastasis in human cervical cancer Hela cells.

RESULTS

GO significantly inhibited cell viability and the number of clones, promoted cell apoptosis, as well as suppressed cell migration and invasion, and destroyed the structure of actin cytoskeleton of Hela cells in a dose-dependent manner in. Moreover, the expression of metastasis-related proteins, including MMP2 and Cdc42, were significantly suppressed by the treatment of GO. And the expression of MMP3 was remarkably increased by Smad inhibitor and the protein levels of MMP3 and ICAM were elevated by the JNK inhibitor in GO-treated Hela cells.

CONCLUSION

GO exhibited inhibitory effects on cell migration and invasion possibly by destroying actin cytoskeleton in Hela cells, which is a potential component of the Smad and JNK signalling pathways.

METHODS

GO was prepared and chracterized by UV visible light absorption spectroscopy and atomic force microscopy. Hela cells were treated with Go at different dose levels. Then, in vitro cytotoxicity of GO was evaluated by the MTT assay, colony-forming assay and cell apoptosis assay. The inhibitory effects of GO on tumor cell migration and invasion as well as actin cytoskeleton were explored using Hela cells.

Synthesis, Characterization and Anti-Cancer Therapeutic Potential of Withanolide-A with 20nm sAuNPs Conjugates Against SKBR3 Breast Cancer Cell Line

Background

Nanotechnology is gaining emerging interest in advanced drug discovery therapeutics due to their tremendous properties including enhanced delivery of therapeutic payload, extensive surface to volume ratio, high permeability, retention behaviors, etc. The gold nanoparticles (AuNPs) are favored due to their advanced features, such as biogenic, tunable physiochemical response, ease in synthesis, and wide range of biomedical applications. The phytochemicals have been focused to design Au nano-carrier-based conjugation for active-targeting drug delivery due to their nano conjugation ability.

Aim

The present study describes the facile synthesis of 20nm spherical AuNPs and their conjugation with reported anti-cancer phytocompound Withanolide-A (1).

Methods

The 20nm sAuNPs were synthesized chemically and characterized their phytochemical gold nanoconjugates through UV-visible spectroscopy, dynamic light scattering (DLS) and transmission electron microscopy (TEM) imaging techniques. The anti-cancer therapeutic potentials were tested with both nanoconjugates and pure WithanolideA (1) by using SKBR3 breast cancer cells line.

Results

The synthesized sAuNPs showed significant conjugation with Withanolide-A and showed stability. Furthermore, these Au nanoconjugates with Withanolide-A (1) significantly induce blockage of SKBR3 cell growth at half maximal active concentration that compared to pure Withanolide-A (1).

Conclusion

Our findings provide a foundation to further progress how they can overcome cancer drug resistance by conjugating active drugs in combination with AuNPs through optimizing the effective drug concentration and removing the surface barrier.

Self-Assembled Peptide-Based Biocomposites for Near-Infrared Light Triggered Drug Release to Tumor Cells

Peptide-based nanomaterials are increasingly gaining popularity due to their specificity, biocompatibility, and biodegradability. In this work, a new multi-layered peptide-based biocomposite for targeting MCF-7 breast cancer cells is developed. The amphipathic Fluorenylmethyloxycarbonyl (Fmoc)-Leu-Ser peptide is synthesized, which is conjugated to a tumor-targeting peptide sequence Gly-Cys-Gly-Asn-Ser to form Fmoc-L-S-G-C-G-N-S (FLS) assemblies. To the FLS assemblies, gold nanorods are then attached to develop drug delivery vehicles (DDVs). The DDVs are entrapped with the anti-cancer drug fulvestrant. Entrapment efficiency is found to be 50.6%. Release studies indicate that irradiating the gold nanorod bound DDVs at NIR wavelength (785 nm) increases drug release by fourfold compared to assemblies that are not irradiated. These results also show higher cytotoxicity and lower cell invasion due to photo-triggered drug release. Furthermore, distinct actin cytoskeletal changes are observed. Such novel peptide-based gold nanorod bound DDVs demonstrate potential in dual targeting of MCF-7 breast cancer cells.

Ribosomes as a nexus between translation and cancer progression: Focus on ribosomal Receptor for Activated C Kinase 1 (RACK1) in breast cancer

Ribosomes coordinate spatiotemporal control of gene expression, contributing to the acquisition and maintenance of cancer phenotype. The link between ribosomes and cancer is found in the roles of individual ribosomal proteins in tumorigenesis and cancer progression, including the ribosomal protein, receptor for activated C kinase 1 (RACK1). RACK1 regulates cancer cell invasion and is localized in spreading initiation centres, structural adhesion complexes containing RNA binding proteins and poly-adenylated mRNAs that suggest a local translation process. As RACK1 is a ribosomal protein directly involved in translation and in breast cancer progression, we propose a new molecular mechanism for breast cancer cell migration and invasion, which considers the molecular differences between epithelial and mesenchymal cell profiles in order to characterize and provide novel targets for therapeutic strategies. Hence, we provide an analysis on how ribosomes translate cancer progression with a final focus on the ribosomal protein RACK1 in breast cancer.

Coordinate β-adrenergic inhibition of mitochondrial activity and angiogenesis arrest tumor growth

Mitochondrial metabolism has emerged as a promising target against the mechanisms of tumor growth. Herein, we have screened an FDA-approved library to identify drugs that inhibit mitochondrial respiration. The β1-blocker nebivolol specifically hinders oxidative phosphorylation in cancer cells by concertedly inhibiting Complex I and ATP synthase activities. Complex I inhibition is mediated by interfering the phosphorylation of NDUFS7. Inhibition of the ATP synthase is exerted by the overexpression and binding of the ATPase Inhibitory Factor 1 (IF1) to the enzyme. Remarkably, nebivolol also arrests tumor angiogenesis by arresting endothelial cell proliferation. Altogether, targeting mitochondria and angiogenesis triggers a metabolic and oxidative stress crisis that restricts the growth of colon and breast carcinomas. Nebivolol holds great promise to be repurposed for the treatment of cancer patients.

ZNF750 represses breast cancer invasion via epigenetic control of prometastatic genes

Breast cancer is the second leading cause of cancer-related deaths among women, largely due to the progression of a significant fraction of primary tumours to the metastatic stage. Here, we show that zinc-finger protein 750 (ZNF750) opposes the migration and invasion of breast cancer cells by repressing a prometastatic transcriptional programme, which includes genes involved in focal adhesion and extracellular matrix interactions, such as LAMB3 and CTNNAL1. Mechanistically, ZNF750 recruits the epigenetic modifiers KDM1A and HDAC1 to the promoter regions of LAMB3 and CTNNAL1, influencing histone marks and transactivating these genomic sites. Gene expression analysis in cancer patient datasets indicated that ZNF750 and its targets were negative prognostic factors in breast cancer. Together, our findings shed light on the molecular mechanism by which ZNF750 regulates cell migration and invasion, suggesting a role in breast cancer metastasis.

SETD3 acts as a prognostic marker in breast cancer patients and modulates the viability and invasion of breast cancer cells

In several carcinomas, the SET Domain Containing 3, Actin Histidine Methyltransferase (SETD3) is associated with oncogenesis. However, there is little knowledge about the role of SETD3 in the progression and prognosis of breast cancer. In this study, we first analyzed the prognostic value of SETD3 in breast cancer patients using the database of the public Kaplan-Meier plotter. Moreover, in vitro assays were performed to assess the role of SETD3 in the viability and capacity of invasion of human breast cancer cell lines. We observed that the high expression of SETD3 was associated with better relapse-free survival (RFS) of the whole collective of 3,951 patients, of Estrogen Receptor-positive, and of Luminal A-type breast cancer patients. However, in patients lacking expression of estrogen-, progesterone- and HER2-receptor, and those affected by a p53-mutation, SETD3 was associated with poor RFS. In vitro analysis showed that SETD3 siRNA depletion affects the viability of triple-negative cells as well as the cytoskeletal function and capacity of invasion of highly invasive MDA-MB-231 cells. Interestingly, SETD3 regulates the expression of other genes associated with cancer such as β-actin, FOXM1, FBXW7, Fascin, eNOS, and MMP-2. Our study suggests that SETD3 expression can act as a subtype-specific biomarker for breast cancer progression and prognosis.

Anillin regulates breast cancer cell migration, growth, and metastasis by non-canonical mechanisms involving control of cell stemness and differentiation

Background

Breast cancer metastasis is driven by a profound remodeling of the cytoskeleton that enables efficient cell migration and invasion. Anillin is a unique scaffolding protein regulating major cytoskeletal structures, such as actin filaments, microtubules, and septin polymers. It is markedly overexpressed in breast cancer, and high anillin expression is associated with poor prognosis. The aim of this study was to investigate the role of anillin in breast cancer cell migration, growth, and metastasis.

Methods

CRISPR/Cas9 technology was used to deplete anillin in highly metastatic MDA-MB-231 and BT549 cells and to overexpress it in poorly invasive MCF10AneoT cells. The effects of anillin depletion and overexpression on breast cancer cell motility in vitro were examined by wound healing and Matrigel invasion assays. Assembly of the actin cytoskeleton and matrix adhesion were evaluated by immunofluorescence labeling and confocal microscopy. In vitro tumor development was monitored by soft agar growth assays, whereas cancer stem cells were examined using a mammosphere formation assay and flow cytometry. The effects of anillin knockout on tumor growth and metastasis in vivo were determined by injecting control and anillin-depleted breast cancer cells into NSG mice.

Results

Loss-of-function and gain-of-function studies demonstrated that anillin is necessary and sufficient to accelerate migration, invasion, and anchorage-independent growth of breast cancer cells in vitro. Furthermore, loss of anillin markedly attenuated primary tumor growth and metastasis of breast cancer in vivo. In breast cancer cells, anillin was localized in the nucleus; however, knockout of this protein affected the cytoplasmic/cortical events, e.g., the organization of actin cytoskeleton and cell-matrix adhesions. Furthermore, we observed a global transcriptional reprogramming of anillin-depleted breast cancer cells that resulted in suppression of their stemness and induction of the mesenchymal to epithelial trans-differentiation. Such trans-differentiation was manifested by the upregulation of basal keratins along with the increased expression of E-cadherin and P-cadherin. Knockdown of E-cadherin restored the impaired migration and invasion of anillin-deficient breast cancer cells.

Conclusion

Our study demonstrates that anillin plays essential roles in promoting breast cancer growth and metastatic dissemination in vitro and in vivo and unravels novel functions of anillin in regulating breast cancer stemness and differentiation.

PTBP1-mediated regulation of AXL mRNA stability plays a role in lung tumorigenesis

AXL is expressed in many types of cancer and promotes cancer cell survival, metastasis and drug resistance. Here, we focus on identifying modulators that regulate AXL at the mRNA level. We have previously observed that the AXL promoter activity is inversely correlated with the AXL expression levels, suggesting that post-transcriptional mechanisms exist that down-regulate the expression of AXL mRNA. Here we show that the RNA binding protein PTBP1 (polypyrimidine tract-binding protein) directly targets the 5′-UTR of AXL mRNA in vitro and in vivo. Moreover, we also demonstrate that PTBP1, but not PTBP2, inhibits the expression of AXL mRNA and the RNA recognition motif 1 (RRM1) of PTBP1 is crucial for this interaction. To clarify how PTBP1 regulates AXL expression at the mRNA level, we found that, while the transcription rate of AXL was not significantly different, PTBP1 decreased the stability of AXL mRNA. In addition, over-expression of AXL may counteract the PTBP1-mediated apoptosis. Knock-down of PTBP1 expression could enhance tumor growth in animal models. Finally, PTBP1 was found to be negatively correlated with AXL expression in lung tumor tissues in Oncomine datasets and in tissue micro-array (TMA) analysis. In conclusion, we have identified a molecular mechanism of AXL expression regulation by PTBP1 through controlling the AXL mRNA stability. These findings may represent new thoughts alternative to current approaches that directly inhibit AXL signaling and may eventually help to develop novel therapeutics to avoid cancer metastasis and drug resistance.

Identification of genes of four malignant tumors and a novel prediction model development based on PPI data and support vector machines

Triple-negative breast cancer (TNBC), colon adenocarcinoma (COAD), ovarian cancer (OV), and glioblastoma multiforme (GBM) are common malignant tumors, in which significant challenges are still faced in early diagnosis, treatment, and prognosis. Therefore, further identification of genes related to those malignant tumors is of great significance for the improvement of management of the diseases. The database of the National Center for Biotechnology Information (NCBI) Gene Expression Omnibus (GEO) repository was used as the data source of gene expression profiles in this study. Malignant tumors genes were selected using a feature selection algorithm of maximal relevance and minimal redundancy (mRMR) and the protein-protein interaction (PPI) network. And finally selected 20 genes as potential related genes. Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were performed on the potential related genes, and different tumor-specific genes and similarities and differences between network modules and pathways were analyzed. Further, using the potential cancer-related genes found above in this study as features, a support vector machine (SVM) model was developed to predict high-risk malignant tumors. As a result, the prediction accuracy reached more than 85%, indicating that such a model can effectively predict the four types of malignant tumors. It is demonstrated that such genes found above in this study indeed play important roles in the differentiation of the four types of malignant tumors, providing basis for future experimental biological validation and shedding some light on the understanding of new molecular mechanisms related to the four types of tumors.

Prognostic role of GPER/Ezrin in triple-negative breast cancer is associated with menopausal status

The role of G protein-coupled estrogen receptor 1 (GPER) signaling, including promotion of Ezrin phosphorylation (which could be activated by estrogen), has not yet been clearly identified in triple-negative breast cancer (TNBC). This study aimed to evaluate the prognostic value of GPER and Ezrin in TNBC patients. Clinicopathologic features including age, menopausal status, tumor size, nuclear grade, lymph node metastasis, AJCC TNM stage, and ER, PR and HER-2 expression were evaluated from 249 TNBC cases. Immunohistochemical staining of GPER and Ezrin was performed on TNBC pathological sections. Kaplan-Meier analyses, as well as logistic regressive and Cox regression model tests were applied to evaluate the prognostic significance between different subgroups. Compared to the GPER-low group, the GPER-high group exhibited higher TNM staging (P = 0.021), more death (P < 0.001), relapse (P < 0.001) and distant events (P < 0.001). Kaplan-Meier analysis showed that GPER-high patients had a decreased OS (P < 0.001), PFS (P < 0.001), LRFS (P < 0.001) and DDFS (P < 0.001) than GPER-low patients. However, these differences in prognosis were not statistically significant in post-menopausal patients (OS, P = 0.8617; PFS, P = 0.1905; LRFS, P = 0.4378; DDFS, P = 0.2538). There was a significant positive correlation between GPER and Ezrin expression level (R = 0.508, P < 0.001) and the effect of Ezrin on survival prognosis corresponded with GPER. Moreover, a multivariable analysis confirmed that GPER and Ezrin level were both significantly associated with poor DDFS (HR: 0.346, 95% CI 0.182-0.658, P = 0.001; HR: 0.320, 95% CI 0.162-0.631, P = 0.001). Thus, overexpression of GPER and Ezrin may contribute to aggressive behavior and indicate unfavorable prognosis in TNBC; this may correspond to an individual's estrogen levels.

Novel secretome-to-transcriptome integrated or secreto-transcriptomic approach to reveal liquid biopsy biomarkers for predicting individualized prognosis of breast cancer patients

Background

Presently, a 50-gene expression model (PAM50) serves as a breast cancer (BC) subtype classifier that is insufficient to distinguish, within each single PAM50-classified subtype, patient subpopulations having different prognosis. There is a pressing need for inexpensive and minimally invasive biomarker tests to easily and accurately predict individuals’ clinical outcomes and response to treatments. Although quantitative proteomic approaches have been developed to identify/profile proteins secreted (secretome) from various cancer cell lines in vitro, missing are the clinicopathological relevance and the associated prognostic value of these secretomic identifications.

Methods

To discover biomarkers to predict individualized prognosis we introduce a new multi-omics (secreto-transcriptomics) method that identifies, in their oncogenically secreted states, candidate markers of BC subtypes whose genes bear patient-specific mRNA expression alterations of prognostic significance. First, we used label-free quantitative (LFQ) proteomics to identify the proteins showing BC-subtypic secretion from a series of BC cell lines representing major BC-subtypes. To determine and externally validate the prognostic value of these secreted proteins, we developed a secreto-transcriptomic approach that discovered a PAM50-subtypic Secretion-Correlated mRNA Expression Pattern (SeCEP) wherein the PAM50-subtypic secretion of select proteins statistically correlated with cis-mRNA expression of their encoding genes in patients of the corresponding PAM50-subtypes. Kaplan-Meier analysis of SeCEP genes was used to identify new liquid biopsy biomarkers for predicting individualized prognosis.

Results

The mRNA expression-to-secretion correlation (SeCEP) pinpointed multiple genes that are fully translated into the oncogenically active secretome in a PAM50-subtypic manner. Further, multiple SeCEP genes in distinct combinations or panels of multiple SeCEP genes were identified as ‘systems prognostic markers’ that showed mRNA co-overexpression patterns in the distinct subpopulations of PAM50-subtypic patients with poor prognosis or high-risk of relapse. Thus, our secreto-transcriptomic approach statistically linked BC subtypic secretome genes with patient-specific information about their mRNA expression alterations and significantly improved the sensitivity and specificity in patient stratification in the context of clinical outcomes or prognosis.

Conclusions

By combining LFQ secretome screening with proteo-transcriptomic retrospective analysis of patient data our integrated multi-omics approach bypasses costly, tedious, genome-wide fishing and predictive modeling that are commonly required to distinguish a few prognostically altered genes from thousands of other non-BC related genes in a genome.

Electronic supplementary material

The online version of this article (10.1186/s12920-019-0530-7) contains supplementary material, which is available to authorized users.

β1 Integrin is essential for fascin-mediated breast cancer stem cell function and disease progression

Breast cancer remains the second cause of tumor‐related mortality in women worldwide mainly due to chemoresistance and metastasis. The chemoresistance and metastasis are attributed to a rare subpopulation with enriched stem‐like characteristics, thus called Cancer Stem Cells (CSCs). We have previously reported aberrant expression of the actin‐bundling protein (fascin) in breast cancer cells, which enhances their chemoresistance, metastasis and enriches CSC population. The intracellular mechanisms that link fascin with its downstream effectors are not fully elucidated. Here, loss and gain of function approaches in two different breast cancer models were used to understand how fascin promotes disease progression. Importantly, findings were aligned with expression data from actual breast cancer patients. Expression profiling of a large breast cancer dataset (TCGA, 530 patients) showed statistically significant correlation between fascin expression and a key adherence molecule, β1 integrin (ITGB1). In vitro manipulation of fascin expression in breast cancer cells exhibited its direct effect on ITGB1 expression. Fascin‐mediated regulation of ITGB1 was critical for several breast cancer cell functions including adhesion to different extracellular matrix, self‐renewability and chemoresistance. Importantly, there was a significant relationship between fascin and ITGB1 co‐expression and short disease‐free as well as overall survival in chemo‐treated breast cancer patients. This novel role of fascin effect on ITGB1 expression and its outcome on cell self‐renewability and chemoresistance strongly encourages for dual targeting of fascin‐ITGB1 axis as a therapeutic approach to halt breast cancer progression and eradicate it from the root.

What's new?

Residual cancer stem cells (CSCs) have the ability to regrow tumors and to metastasize to distant organs, resulting in disease relapse and increased cancer mortality. In breast cancer, CSC populations are enriched by aberrant expression of the actin‐bundling protein fascin, induction of which is also associated with chemoresistance and metastasis. In this study, fascin was found to upregulate β1 integrin (ITGB1) expression, an effect that proved critical to breast cancer cell adhesion and self‐renewal. Coexpression of fascin and ITGB1 was associated with decreased survival in chemotherapy‐treated breast cancer patients. The findings identify the fascin‐ITGB1 axis as a potential therapeutic target.

Girdin/GIV regulates collective cancer cell migration by controlling cell adhesion and cytoskeletal organization

Pathological observations show that cancer cells frequently invade the surrounding stroma in collective groups rather than through single cell migration. Here, we studied the role of the actin-binding protein Girdin, a specific regulator of collective migration of neuroblasts in the brain, in collective cancer cell migration. We found that Girdin was essential for the collective migration of the skin cancer cell line A431 on collagen gels as well as their fibroblast-led collective invasion in an organotypic culture model. We provide evidence that Girdin binds to β-catenin that plays important roles in the Wnt signaling pathway and in E-cadherin-mediated cell-cell adhesion. Girdin-depleted cells displayed scattering and impaired E-cadherin-specific cell-cell adhesion. Importantly, Girdin depletion led to impaired cytoskeletal association of the β-catenin complex, which was accompanied by changes in the supracellular actin cytoskeletal organization of cancer cell cohorts on collagen gels. Although the underlying mechanism is unclear, this observation is consistent with the established role of the actin cytoskeletal system and cell-cell adhesion in the collective behavior of cells. Finally, we showed the correlation of the expression of Girdin with that of the components of the E-cadherin complex and the differentiation of human skin cancer. Collectively, our results suggest that Girdin is an important modulator of the collective behavior of cancer cells.

Application of kinomic array analysis to screen for altered kinases in atrial fibrillation remodeling

BACKGROUND

Dysregulation of protein kinase-mediated signaling is an early event in many diseases, including the most common clinical cardiac arrhythmia, atrial fibrillation (AF). Kinomic profiling represents a promising technique to identify candidate kinases.

OBJECTIVE

In this study we used kinomic profiling to identify kinases altered in AF remodeling using atrial tissue from a canine model of AF (atrial tachypacing).

METHODS

Left atrial tissue obtained in a previous canine study was used for kinomic array (containing 1024 kinase pseudosubstrates) analysis. Three groups of dogs were included: nonpaced controls and atrial tachypaced dogs, which were contrasted with geranylgeranylacetone-treated dogs with AF, which are protected from AF promotion, to enhance specificity of detection of putative kinases.

RESULTS

While tachypacing changed activity of 50 kinases, 40 of these were prevented by geranylgeranylacetone and involved in differentiation and proliferation (SRC), contraction, metabolism, immunity, development, cell cycle (CDK4), and survival (Akt). Inhibitors of Akt (MK2206) and CDK4 (PD0332991) and overexpression of a dominant-negative CDK4 phosphorylation mutant protected against tachypacing-induced contractile dysfunction in HL-1 cardiomyocytes. Moreover, patients with AF show down- and upregulation of SRC and Akt phosphorylation, respectively, similar to findings of the kinome array.

CONCLUSION

Contrasting kinomic array analyses of controls and treated subjects offer a versatile tool to identify kinases altered in atrial remodeling owing to tachypacing, which include Akt, CDK4, and SRC. Ultimately, pharmacological targeting of altered kinases may offer novel therapeutic possibilities to treat clinical AF.

IntLIM: integration using linear models of metabolomics and gene expression data

BACKGROUND

Integration of transcriptomic and metabolomic data improves functional interpretation of disease-related metabolomic phenotypes, and facilitates discovery of putative metabolite biomarkers and gene targets. For this reason, these data are increasingly collected in large (> 100 participants) cohorts, thereby driving a need for the development of user-friendly and open-source methods/tools for their integration. Of note, clinical/translational studies typically provide snapshot (e.g. one time point) gene and metabolite profiles and, oftentimes, most metabolites measured are not identified. Thus, in these types of studies, pathway/network approaches that take into account the complexity of transcript-metabolite relationships may neither be applicable nor readily uncover novel relationships. With this in mind, we propose a simple linear modeling approach to capture disease-(or other phenotype) specific gene-metabolite associations, with the assumption that co-regulation patterns reflect functionally related genes and metabolites.

RESULTS

The proposed linear model, metabolite ~ gene + phenotype + gene:phenotype, specifically evaluates whether gene-metabolite relationships differ by phenotype, by testing whether the relationship in one phenotype is significantly different from the relationship in another phenotype (via a statistical interaction gene:phenotype p-value). Statistical interaction p-values for all possible gene-metabolite pairs are computed and significant pairs are then clustered by the directionality of associations (e.g. strong positive association in one phenotype, strong negative association in another phenotype). We implemented our approach as an R package, IntLIM, which includes a user-friendly R Shiny web interface, thereby making the integrative analyses accessible to non-computational experts. We applied IntLIM to two previously published datasets, collected in the NCI-60 cancer cell lines and in human breast tumor and non-tumor tissue, for which transcriptomic and metabolomic data are available. We demonstrate that IntLIM captures relevant tumor-specific gene-metabolite associations involved in known cancer-related pathways, including glutamine metabolism. Using IntLIM, we also uncover biologically relevant novel relationships that could be further tested experimentally.

CONCLUSIONS

IntLIM provides a user-friendly, reproducible framework to integrate transcriptomic and metabolomic data and help interpret metabolomic data and uncover novel gene-metabolite relationships. The IntLIM R package is publicly available in GitHub ( https://github.com/mathelab/IntLIM ) and includes a user-friendly web application, vignettes, sample data and data/code to reproduce results.

RAC1 GTP-ase signals Wnt-beta-catenin pathway mediated integrin-directed metastasis-associated tumor cell phenotypes in triple negative breast cancers

The acquisition of integrin-directed metastasis-associated (ID-MA) phenotypes by Triple-Negative Breast Cancer (TNBC) cells is caused by an upregulation of the Wnt-beta-catenin pathway (WP). We reported that WP is one of the salient genetic features of TNBC. RAC-GTPases, small G-proteins which transduce signals from cell surface proteins including integrins, have been implicated in tumorigenesis and metastasis by their role in essential cellular functions like motility. The collective percentage of alteration(s) in RAC1 in ER+ve BC was lower as compared to ER-ve BC (35% vs 57%) (brca/tcga/pub2015). High expression of RAC1 was associated with poor outcome for RFS with HR=1.48 [CI: 1.15-1.9] p=0.0019 in the Hungarian ER-veBC cohort. Here we examined how WP signals are transduced via RAC1 in the context of ID-MA phenotypes in TNBC. Using pharmacological agents (sulindac sulfide), genetic tools (beta-catenin siRNA), WP modulators (Wnt-C59, XAV939), RAC1 inhibitors (NSC23766, W56) and WP stimulations (LWnt3ACM, Wnt3A recombinant) in a panel of 6-7 TNBC cell lines, we studied fibronectin-directed (1) migration, (2) matrigel invasion, (3) RAC1 and Cdc42 activation, (4) actin dynamics (confocal microscopy) and (5) podia-parameters. An attenuation of WP, which (a) decreased cellular levels of beta-catenin, as well as its nuclear active-form, (b) decreased fibronectin-induced migration, (c) decreased invasion, (d) altered actin dynamics and (e) decreased podia-parameters was successful in blocking fibronectin-mediated RAC1/Cdc42 activity. Both Wnt-antagonists and RAC1 inhibitors blocked fibronectin-induced RAC1 activation and inhibited the fibronectin-induced ID-MA phenotypes following specific WP stimulation by LWnt3ACM as well as Wnt3A recombinant protein. To test a direct involvement of RAC1-activation in WP-mediated ID-MA phenotypes, we stimulated brain-metastasis specific MDA-MB231BR cells with LWnt3ACM. LWnt3ACM-stimulated fibronectin-directed migration was blocked by RAC1 inhibition in MDA-MB231BR cells. In the light of our previous report that WP upregulation causes ID-MA phenotypes in TNBC tumor cells, here we provide the first mechanism based evidence to demonstrate that WP upregulation signals ID-MA tumor cell phenotypes in a RAC1-GTPase dependent manner involving exchange-factors like TIAM1 and VAV2. Our study demonstrates for the first time that beta-catenin-RAC1 cascade signals integrin-directed metastasis-associated tumor cell phenotypes in TNBC.

Noncanonical hedgehog pathway activation through SRF-MKL1 promotes drug resistance in basal cell carcinomas

Hedgehog pathway-dependent cancers can escape smoothened (SMO) inhibition through canonical pathway mutations, however, 50% of resistant BCCs lack additional variants in hedgehog genes. Here we use multi-dimensional genomics in human and mouse resistant BCCs to identify a non-canonical hedgehog activation pathway driven by the transcription factor, serum response factor (SRF). Active SRF along with its co-activator megakaryoblastic leukemia 1 (MKL1) form a novel protein complex and share chromosomal occupancy with the hedgehog transcription factor GLI1, causing amplification of GLI1 transcriptional activity. We show cytoskeletal activation by Rho and the formin family member Diaphanous (mDia) are required for SRF/MKL-driven GLI1 activation and tumor cell viability. Remarkably, we use nuclear MKL1 staining in mouse and human patient tumors to define drug responsiveness to MKL inhibitors highlighting the therapeutic potential of targeting this pathway. Thus, our studies illuminate for the first time cytoskeletal-driven transcription as a personalized therapeutic target to combat drug resistant malignancies.

MIEN1 drives breast tumor cell migration by regulating cytoskeletal-focal adhesion dynamics

Migration and invasion enhancer 1 (MIEN1) is an important regulator of cell migration and invasion. MIEN1 overexpression represents an oncogenic event that promotes tumor cell dissemination and metastasis. The underlying mechanism by which MIEN1 regulates migration and invasion has yet to be deciphered. Here, we demonstrate that MIEN1 acts as a cytoskeletal-signaling adapter protein to drive breast cancer cell migration. MIEN1 localization is concentrated underneath the actin-enriched protrusive structures of the migrating breast cancer cells. Depletion of MIEN1 led to the loss of actin-protrusive structures whereas the over-expression of MIEN1 resulted in rich and thick membrane extensions. Knockdown of MIEN1 also decreased the cell-substratum adhesion, suggesting a role for MIEN1 in actin cytoskeletal dynamics. Our results show that MIEN1 supports the transition of G-actin to F-actin polymerization and stabilizes F-actin polymers. Additionally, MIEN1 promotes cellular adhesion and actin dynamics by inducing phosphorylation of FAK at Tyr-925 and reducing phosphorylation of cofilin at Ser-3, which results in breast cancer cell migration. Collectively, our data show that MIEN1 plays an essential role in maintaining the plasticity of the dynamic membrane-associated actin cytoskeleton, which leads to an increase in cell motility. Hence, targeting MIEN1 might represent a promising means to prevent breast tumor metastasis.

The crosstalk between breast carcinoma-associated fibroblasts and cancer cells promotes RhoA-dependent invasion via IGF-1 and PAI-1

Carcinoma-associated fibroblasts (CAFs) can remodel the extracellular matrix to promote cancer cell invasion, but the paracrine signaling between CAFs and cancer cells that regulates tumor cell migration remains to be identified. To determine how the interaction between CAFs and cancer cells modulates the invasiveness of cancer cells, we developed a 3-dimensional co-culture model composed of breast cancer (BC) MDA-MB-231 cell spheroids embedded in a collagen gel with and without CAFs. We found that the crosstalk between CAFs and cancer cells promotes invasion by stimulating the scattering of MDA-MB-231 cells, which was dependent on RhoA/ROCK/phospho MLC signaling in cancer cells but independent of RhoA in CAFs. The activation of RhoA/ROCK in cancer cells activates MLC and increases migration, while the genetic-down-regulation of RhoA and pharmacological inhibition of ROCK reduced cell scattering and invasion. Two distinct mechanisms induced the activation of the RhoA/ROCK pathway in MDA-MB-231 cells, the secretion of IGF-1 by CAFs and the upregulation of PAI-1 in cancer cells. In an orthotopic model of BC, IGF-1R inhibition decreased the incidence of lung metastasis, while Y27632-inhibition of ROCK enhanced the lung metastasis burden, which was associated with an increased recruitment of CAFs and expression of PAI-1. Thus the crosstalk between CAFs and BC cells increases the secretion of IGF-1 in CAFs and PAI-1 activity in cancer cells. Both IGF1 and PAI-1 activate RhoA/ROCK signaling in cancer cells, which increases cell scattering and invasion.

Peroxiredoxin-1 promotes cell proliferation and metastasis through enhancing Akt/mTOR in human osteosarcoma cells

Osteosarcoma is characterized by high propensity for metastasis, especially to the lung, which is the main cause of death. Peroxiredoxin-1 (PRDX1) plays significant roles in multiple processes of initiation and progression of tumorogenesis. However, whether PRDX1 participates in metastasis of osteosarcoma remains unknown. Here, we demonstrate that PRDX1 overexpressed in osteosarcoma tissues comparing to adjacent non-tumor tissues. Two independent cohorts of patients showed high level of PRDX1 correlated with clinicopathological features such as larger tumor size and advanced tumor metastasis stage. While patients with high PRDX1 level have poor prognosis. Notably, expression level of PRDX1 especially increased in lung lesion of osteosarcoma patients, indicating that PRDX1 may promote lung metastasis. Ectopic expression of PRDX1 promotes osteosarcoma cell migration and metastasis in vitro and in vivo, whereas knockdown of PRDX1 expression suppresses cell metastatic behaviors such as invasion and migration. Furthermore, we found that PRDX1 promotes cells metastasis through enhancing Akt/mTOR signal pathway. Taken together, our findings prove the important role of PRDX1 in the molecular etiology of osteosarcoma and suggest that PRDX1 may be a novel prognostic biomarker and therapeutic target for osteosarcoma.

FSCN1 gene polymorphisms: biomarkers for the development and progression of breast cancer

Breast cancer is a major cause of cancer mortality worldwide. Fascin-1 (FSCN1) is an actin-binding protein found in mammalian cells, including endothelial, neuronal and mesenchymal cells. FSCN1 overexpression has been indicated in breast cancer patients. However, scant information is available regarding the association between FSCN1 single nucleotide polymorphisms (SNPs) and the risk or prognosis of breast cancer. We report on the association between 6 SNPs of the FSCN1 gene (rs56156320, rs8772, rs3801004, rs2966447, rs852479 and rs1640233) and breast cancer susceptibility as well as clinical outcomes in 316 patients with breast cancer and in 222 healthy controls. Carriers of the AC or AC + CC allele of the variant rs56156320 were at greater risk of breast cancer compared with wild-type (AA) carriers. Moreover, carriers of at least one G allele in rs3801004 were likely to progress to stage III/IV disease and lymph node metastasis. Individuals with at least one T allele at FSCN1 SNP rs2966447 were at higher risk of developing pathologic grade G3 disease. Furthermore, individuals bearing the C/C haplotype at SNPs rs56156320 and rs3801004 had nearly twice the risk of breast cancer. Our results indicate that genetic variations in the FSCN1 gene may serve as an important predictor of early-stage breast cancer.

The down-regulation of TAPP2 inhibits the migration of esophageal squamous cell carcinoma and predicts favorable outcome

Tandem pH domain-containing proteins TAPP1 and TAPP2 are adaptor proteins that specifically bind to phosphatidylinositol-3,4-bisphosphate, or PI(3,4)P2, a product of phosphoinositide 3-kinases (PI3K). Although PI3K enzymes have multiple functions in cell biology, including cell migration, the functions of PI (3, 4) P2 and its binding proteins are not well understood. Previously studies found that TAPP2 is highly expressed in primary leukemic B cells that have strong migratory capacity. However, the function and underlying mechanisms of TAPP2 in ESCC remain largely unknown. In the present study, we investigated the level of TAPP2 in human esophageal squamous cell carcinoma (ESCC) tissues and in corresponding adjacent non-tumor tissues by immunohistochemistry (IHC) and western blot analyses. TAPP2 protein level was increased in ESCC tissues compared with corresponding adjacent non-tumor tissues. In vitro experiments showed that under-expression of TAPP2 reduced ESCC cell TE1 migration by wound-healing assays and transwell migration assays, and it was concurrent with the decreased expression of the phosphorylation of AKT. Taken together, these findings suggested that TAPP2 serves as oncogenic gene in ESCC and may serve as a new target for ESCC therapy.