Tumor metastasis suppressor functions of Ets transcription factor through integrin ß3-mediated signaling pathway.

Prostate-derived Ets transcription factor (PDEF) is a member of the Ets transcription factor family originally identified in prostate tissue. PDEF functions like a tumor metastasis suppressor. Although the underlying mechanism is not very clear. In this study, a significantly higher expression level of integrin ß3 was observed in aggressive prostate cancer (PCa) cells; PC3, that lack the expression of PDEF, was confirmed by quantitative real-time polymerase chain reaction and the immunoblot analysis. Dual immunofluorescence studies have confirmed the lower expression of PDEF and higher expression level of integrin ß3 in PCa cells compared with non-tumorigenic prostate epithelial RWPE-1 cells. Then, it was attempted to identify integrin ß3-mediated downstream signaling pathways that modulate actin cytoskeleton remodeling in PCa cells. Inhibition of PDEF by RNA interference (PDEFKD ) in DU145 cells confirmed by transcript and western blot analysis, exhibited significantly higher expression level of integrin ß3 and its downstream signaling molecules talin and paxillin, associated with promoting migration and invasion of cells. Given the involvement of integrin-mediated invasion of cells, PDEFKD DU145 cells were treated with Echistatin, a potent integrin ß3-specific antagonist and found that the cells significantly reduced the transcript and protein expression levels of talin and paxillin; and reduced the invasion of cells. Overall, the cytoskeleton remodeling by integrin ß3, modulated by PDEF, may represent a novel molecular link with cell adhesion and migration leading to the suppression of metastasis in PCa cells.

The basics of epithelial-mesenchymal transition (EMT): A study from a structure, dynamics, and functional perspective.

Epithelial-mesenchymal transition (EMT) is a key step in transdifferentiation process in solid cancer development. Forthcoming evidence suggest that the stratified program transforms polarized, immotile epithelial cells to migratory mesenchymal cells associated with enhancement of breast cancer stemness, metastasis, and drug resistance. It involves primarily several signaling pathways, such as transforming growth factor-ß (TGF-ß), cadherin, notch, plasminogen activator protein inhibitor, urokinase plasminogen activator, and WNT/beta catenin pathways. However, current understanding on the crosstalk of multisignaling pathways and assemblies of key transcription factors remain to be explored. In this review, we focus on the crosstalk of signal transduction pathways linked to the current therapeutic and drug development strategies. We have also performed the computational modeling on indepth the structure and conformational dynamic studies of regulatory proteins and analyze molecular interactions with their associate factors to understand the complicated process of EMT in breast cancer progression and metastasis. Electrostatic potential surfaces have been analyzed that help in optimization of electrostatic interactions between the protein and its ligand. Therefore, understanding the biological implications underlying the EMT process through molecular biology with biocomputation and structural biology approaches will enable the development of new therapeutic strategies to sensitize tumors to conventional therapy and suppress their metastatic phenotype.

Diagnostic and Prognostic Biomarkers in ovarian cancer and the potential roles of cancer stem cells - An updated review.

Ovarian carcinomas relate to highest death rate in gynecologic malignancies as absence of symptoms shield the disease in the early stage. Current evidences have been devoted to discovering early effective screening mechanism prior to the onset of clinical symptoms. Therefore, biomarkers are the crucial tools that are capable of predicting progression, risk stratification and overall therapeutic benefit to fight against this deadly disease. Although recent studies have revealed serum protein markers, CA-125, HE4, mesothelin etc. have higher sensitivity and specificity at the early stages of the cancer; the critical questions arise regarding the applicability and reproducibility of genomic profiling across different patient groups. Hence, our hypothesis is that the panels of signature biomarkers will be much more effective to improve the diagnosis and prediction of patient survival outcome with high sensitivity and specificity. Ovarian cancer is heterogeneous in nature and contain a sub-population of stem cell-like characteristics that has the ability to grow as anchorage-independent manner and subsequently is able to metastasize. Highly tumorigenic and chemotherapy-resistant cancer stem cells (CSCs)-specific biomarkers therefore reflects the interesting possibilities to be targeted to minimize the high frequency of relapse and resistance to drugs. Several putative ovarian CSC markers such as CD24, CD44, CD133, SSEA have already been proposed in recent studies, yet, a large panel of updated biomarkers have high clinical relevance to define the prospective isolation of viable circulating CSCs. Therefore, this review highlights current evidence based updated ovarian cancer specific prognostic and diagnostic biomarkers and potential importance of CSCs in context of tumorigenicity and metastatic activity for fundamental biological and clinical implications.

Cadherin profiling for therapeutic interventions in Epithelial Mesenchymal Transition (EMT) and tumorigenesis.

The major hallmarks of Epithelial-Mesenchymal Transition (EMT) is the loss of epithelial cell polarity and loss of expression of the cell- cell adhesion molecule like E-cadherin and acquired mesenchymal cells marker called N-Cadherin. This phenotypical changes of E-M plasticity of cells is extensively considered to be a crucial factor for tumor cells invasion and cancer metastasis; landmark events for transforming a locally growing tumor (benign tumor) into a systemic and live-threatening disease (malignant tumor). Cadherin molecules are adherens junction proteins and expressed as multiple isoforms. Cadherin switching occurs during normal tissue developmental processes; also recapitulates the increasing aggressive behavior and metastatic nature of cancer cells when E-Cadherin converts to N-Cadherin, in particular. There are several mechanisms established that cadherin switching and some of the underlying pathways involves multiple steps associated with migration and invasion of cancer cells, and finally colonization of micro metastatic lesions to form macro-metastasis. Inhibition of metastasis is complicated by the plasticity of cancer cells behaviors and the evolving nature of microenvironment. Although there is no clear evidence how that dynamic structural switching of cadherin family member occurs, stabilized and eventually influence cell behavior, phenotypic transformations and initiate tumorigenesis. Therefore, we emphasize here the major functions of over 20 existing human cadherins in tissue integrity and stability as well as mechanistic understanding on recent work of cadherin ectodomain-mediated adhesion, functional studies of the cell-cell adhesion through key signaling intermediates interacting with other binding partners. We hope understanding on how the dynamic all existing cadherins influence the cell behavior can be targeted to design possible therapeutic interventions to combat its activity and prevent tumor cell growth, invasion and metastasis.

Understanding the role of structural integrity and differential expression of integrin profiling to identify potential therapeutic targets in breast cancer.

Breast cancer is found to be the most prevalent neoplasm in women worldwide. Despite the function of physically tethering cells to the matrix, transmembrane protein integrins are crucially involved in diverse cellular functions such as cell differentiation, proliferation, invasion, migration, and metastasis. Dysregulation of integrins and their interactions with the cells and their microenvironment can trigger several signaling cues that determine the cell fate decision. In this review, we spotlight all pre-existing integrin molecules, their structure, molecular interactions motifs, and function through several cross talks with kinase receptors. We also discuss the role of these integrins as potential prognostic and therapeutic targets and also in the regulation of breast cancer cells differentiation. Understanding of integrin structure and their motifs for ligand interactions in this context will enable the development of new therapeutic approaches to sensitize the tumors and their microenvironment to conventional therapy and overall suppress their metastatic phenotype.

Graphene oxide layer decorated gold nanoparticles based immunosensor for the detection of prostate cancer risk factor.

In this work, we report a novel electrochemical immunosensor based on gold nanoparticles deposited on the surface of graphene oxide layers and was used for immobilization of monoclonal anti-PSA antibody via EDC/NHS coupling method to detect prostate-specific antigen (PSA), a valuable biomarker for early detection of prostate cancer. To confirm the functionality of the antibody, we performed immunofluorescence staining using human prostate adenocarcinoma cells, LNCaP. Scanning Electron Microscopy (SEM), cyclic voltammetry, and other electrochemical techniques were used to characterize the resulting electrode surface. Unlike the previous research, this novel immunosensor functions very well with a low detection limit of 0.24 fgmL-1 at signal to noise ratio of 3; furthermore, it exhibits a significantly increased electron transfer and high sensitivity of 5.4 µA fgmL-1 with regression coefficient (R2 = 0.99) toward PSA. The immunosensor was verified for selective and accurate detection of PSA in human serum with recovery of 97.67%. Overall, data suggested that our developed biosensor holds great promise as a useful alternative diagnostic tool for the detection of different cancer biomarkers, in particular PSA present in biological samples.

The transcription factor sterile alpha motif (SAM) pointed domain-containing ETS transcription factor (SPDEF) is required for E-cadherin expression in prostate cancer cells.

Loss of E-cadherin is one of the key steps in tumor progression. Our previous studies demonstrate that SAM pointed domain-containing ETS transcription factor (SPDEF) inhibited prostate cancer metastasis in vitro and in vivo. In the present study, we evaluated the relationship between SPDEF and E-cadherin expression in an effort to better understand the mechanism of action of SPDEF in prostate tumor cell invasion and metastasis. The results presented here demonstrate a direct correlation between expression of E-cadherin and SPDEF in prostate cancer cells. Additional data demonstrate that modulation of E-cadherin and SPDEF had similar effects on cell migration/invasion. In addition, siRNA-mediated knockdown of E-cadherin was sufficient to block the effects of SPDEF on cell migration and invasion. We also show that stable forced expression of SPDEF results in increased expression of E-cadherin, whereas down-regulation of SPDEF decreased E-cadherin expression. In addition, we demonstrate that SPDEF expression is not regulated by E-cadherin. Moreover, our chromatin immunoprecipitation and luciferase reporter assay revealed that SPDEF occupies E-cadherin promoter site and acts as a direct transcriptional inducer of E-cadherin in prostate cancer cells. Taken together, to the best of our knowledge, these studies are the first demonstrating requirement of SPDEF for expression of E-cadherin, an essential epithelial cell junction protein. Given that loss of E-cadherin is a central tenant in tumor metastasis, the results of our studies, by providing a new mechanism for regulation of E-cadherin expression, could have far reaching impact.

Oxalate upregulates expression of IL-2Rß and activates IL-2R signaling in HK-2 cells, a line of human renal epithelial cells.

The role of inflammation in oxalate-induced nephrolithiasis is debated. Our gene expression study indicated an increase in interleukin-2 receptor ß (IL-2Rß) mRNA in response to oxalate (Koul S, Khandrika L, Meacham RB, Koul HK. PLoS ONE 7: e43886, 2012). Herein, we evaluated IL-2Rß expression and its downstream signaling pathway in HK-2 cells in an effort to understand the mechanisms of oxalate nephrotoxicity. HK-2 cells were exposed to oxalate for various time points in the presence or absence of SB203580, a specific p38 MAPK inhibitor. Gene expression data were analyzed by Ingenuity Pathway Analysis software. mRNA expression was quantitated via real-time PCR, and changes in protein expression/kinase activation were analyzed by Western blotting. Exposure of HK-2 cells to oxalate resulted in increased transcription of IL-2Rß mRNA and increased protein levels. Oxalate treatment also activated the IL-2Rß signaling pathway (JAK1/STAT5 phosphorylation). Moreover, the increase in IL-2Rß protein was dependent upon p38 MAPK activity. These results suggest that oxalate-induced activation of the IL-2Rß pathway may lead to a plethora of cellular changes, the most common of which is the induction of inflammation. These results suggest a central role for the p38 MAPK pathway in mediating the effects of oxalate in renal cells, and additional studies may provide the key to unlocking novel biochemical targets in stone disease.

Polyamidoamine dendrimer decorated graphene oxide as a pH-sensitive nanocarrier for the delivery of hydrophobic anticancer drug quercetin: a remedy for breast cancer.

OBJECTIVES: The aim of this study was to investigate the potential of poly(amido amine) (PAMAM) dendrimer decorated graphene oxide (GO) based nanocarrier for targeted delivery of a hydrophobic anticancer drug, quercetin (QSR). METHODS: GO-PAMAM was successfully synthesized by covalent bonding between GO and NH2-terminated PAMAM dendrimer (zero generation). To investigate drug loading performance, QSR was loaded on the surface of GO as well as GO-PAMAM. Further, the release behaviour of QSR-loaded GO-PAMAM was studied. Finally, an in-vitro sulforhodamine B assay was performed in HEK 293T epithelial cells and MDA MB 231 breast cancer cells. KEY FINDINGS: It was observed that GO-PAMAM shows higher QSR loading capacity compared to GO. Also, synthesized nanocarrier exhibits controlled as well as pH-responsive release of QSR and the amount of QSR released at pH 4 was approximately two times higher than the release at pH 7.4. Furthermore, GO-PAMAM was found to be biocompatible for HEK 293T cells, and a high cytotoxic effect was observed for QSR-loaded GO-PAMAM on MDA MB 231 cells. CONCLUSIONS: The present investigation highlights the potential application of synthesized hybrid materials as a nanocarrier with excellent loading and controlled releasing efficiency for the delivery of the hydrophobic anticancer drug.

Falcipains: Biochemistry, target validation and structure-activity relationship studies of inhibitors as antimalarials.

Malaria is a tropical disease with significant morbidity and mortality burden caused by Plasmodium species in Africa, the Middle East, Asia, and South America. Pathogenic Plasmodium species have lately become increasingly resistant to approved chemotherapeutics and combination therapies. Therefore, there is an emergent need for identifying new druggable targets and novel chemical classes against the parasite. Falcipains, cysteine proteases required for heme metabolism in the erythrocytic stage, have emerged as promising drug targets against Plasmodium species that infect humans. This perspective discusses the biology, biochemistry, structural features, and genetics of falcipains. The efforts to identify selective or dual inhibitors and their structure-activity relationships are reviewed to give a perspective on the design of novel compounds targeting falcipains for antimalarial activity evaluating reasons for hits and misses for this important target.

Dual Drug Loaded Potassium-contained Graphene Oxide as a Nanocarrier in Cocktailed Drug Delivery for the Treatment of Human Breast Cancer.

BACKGROUND: The combinatorial use of anticancer drugs, dual or multiple, with a specific nanocarrier is one of the most promising attempts in drug delivery. The current work reports potassium contained graphene oxide (K-GO) as a nanocarrier in the drug delivery system of two anticancer drugs, gefitinib (GEF) and camptothecin (CPT), simultaneously. METHODS: To characterize K-GO, K-GO-related single and combined drug systems, different techniques have been performed and studied using the following spectroscopic tools, such as Thermo Gravimetric Analysis (TGA 4000), UV-visible spectroscopy, Raman spectroscopy, and Transmission electron microscopy (TEM). The in vitro cytotoxicity tests of K-GO, single drug system, and the combined drug system were also performed in the human breast cancer MDA-MB-231 cells. RESULTS: The release profile of the dual drug conjugates grafted onto the surface of K-GO was found to be up to 38% in PBS solution over 72 hours. The percentage of MDA-MB-231 cell viability was about 18% when treated with K-GO-GEF-CPT combined system; for K-GO, K-GO-GEF, and K-GO-CPT, the cell viability was 79%, 31%, and 32%, respectively. CONCLUSION: We studied the loading, release, and delivery of two anticancer drugs onto the fluorescent nanocarrier. Features, such as superb aqueous solubility, excellent biocompatibility, richness in potassium, and fluorescent nature, which can monitor the delivery of drugs, make them a promising nanocarrier for single or multiple drug delivery. Furthermore, our novel findings revealed that the loading capacity and cytotoxicity of the combined drug-loaded system are superior to the capacity of the individual drug system for human breast cancer cells.

Corrigendum: identification and validation of lncRNA-SNHG17 in lung adenocarcinoma: a novel prognostic and diagnostic indicator.

[This corrects the article DOI: 10.3389/fonc.2022.929655.].

Identification and Validation of lncRNA-SNHG17 in Lung Adenocarcinoma: A Novel Prognostic and Diagnostic Indicator.

Background: Lung cancer has the highest death rate among cancers globally. Accumulating evidence has indicated that cancer-related inflammation plays an important role in the initiation and progression of lung cancer. However, the prognosis, immunological role, and associated regulation axis of inflammatory response-related gene (IRRGs) in non-small-cell lung cancer (NSCLC) remains unclear. Methods: In this study, we perform comprehensive bioinformatics analysis and constructed a prognostic inflammatory response-related gene (IRRGs) and related competing endogenous RNA (ceRNA) network. We also utilized the Pearson's correlation analysis to determine the correlation between IRRGs expression and tumor mutational burden (TMB), microsatellite instability (MSI), tumor-immune infiltration, and the drug sensitivity in NSCLC. Growth curve and Transwell assay used to verify the function of SNHG17 on NSCLC progression. Results: First, we found that IRRGs were significantly upregulated in lung cancer, and its high expression was correlated with poor prognosis; high expression of IRRGs was significantly correlated with the tumor stage and poor prognosis in lung cancer patients. Moreover, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment indicated that these IRRGs are mainly involved in the inflammatory and immune response-related signaling pathway in the progression of NSCLC. We utilized 10 prognostic-related genes to construct a prognostic IRRGs model that could predict the overall survival of lung adenocarcinoma (LUAD) patients possessing high specificity and accuracy. Our evidence demonstrated that IRRGs expression was significantly correlated with the TMB, MSI, immune-cell infiltration, and diverse cancer-related drug sensitivity. Finally, we identified the upstream regulatory axis of IRRGs in NSCLC, namely, lncRNA MIR503HG/SNHG17/miR-330-3p/regulatory axis. Finally, knockdown of SNHG17 expression inhibited lung adenocarcinoma (LUAD) cell proliferation and migration. Our findings confirmed that SNHG17 is a novel oncogenic lncRNA and may be a biomarker for the prognosis and diagnosis of LUAD. Conclusion: DNA hypomethylation/lncRNA MIR503HG/SNHG17/microRNA-330-3p/regulatory axis may be a valuable biomarker for prognosis and is significantly correlated with immune cell infiltration in lung cancer.

Current advances in prognostic and diagnostic biomarkers for solid cancers: Detection techniques and future challenges.

Solid cancers are one of the leading causes of cancer related deaths, characterized by rapid growth of tumour, and local and distant metastases. Current advances on multimodality care have substantially improved local control and metastasis-free survival of patients by resection of primary tumour. The major concern in disease prognosis is the timely detection of resectable or metastatic tumour, thus reinforcing the need for identification of biomarkers for premalignant lesions of solid cancer. This ultimately improves the outcome for the patients. Therefore, the purpose of this review is to update the recent advancements on prognostic and diagnostic biomarkers to enhance early detection of common solid cancers including, breast, lung, colorectal, prostate and stomach cancer. We also provide an insight into Food and Drug Administration (FDA)-approved solid cancers biomarkers; various conventional techniques used for detection of prognostic and diagnostic biomarkers and discuss approaches to turn challenges in this field into opportunities.

Polymer grafted magnetic graphene oxide as a potential nanocarrier for pH-responsive delivery of sparingly soluble quercetin against breast cancer cells.

In this work, polymer grafted magnetic graphene oxide (GO-PVP-Fe3O4) was successfully synthesized for efficient delivery of anticancer drug. Firstly, GO was functionalized with the hydrophilic and biocompatible polymer polyvinylpyrrolidone (PVP) and then grafted with magnetic nanoparticles (Fe3O4) through an easy and effective chemical co-precipitation method. Quercetin (QSR) as an anticancer drug was loaded onto the surface of GO-PVP-Fe3O4 via non-covalent interactions. The drug loading capacity was as high as 1.69 mg mg-1 and the synthesized magnetic nanocarrier shows pH-responsive controlled release of QSR. The cellular cytotoxicity of the synthesized nanocarrier with and without drugs was investigated in human breast cancer MDA MB 231 cells and their effects compared on non-tumorigenic epithelial HEK 293T cells. These results reveal that the drug loaded GO-PVP-Fe3O4 nanohybrid was found to be more toxic than the free drug towards MDA MB 231 cells and exhibits biocompatibility towards HEK 293T cells. Overall, a smart drug delivery system including polymer grafted magnetic graphene oxide as a pH-responsive potential nanocarrier could be beneficial for targeted drug delivery, controlled by an external magnetic field as an advancement in chemotherapy against cancer.

Biosensors based detection of novel biomarkers associated with COVID-19: Current progress and future promise.

The pandemic situation of COVID-19 has caused global alarm in health care, devastating loss of lives, strangled economy, and paralysis of normal livelihood. The high inter-individual transmission rate created havoc in the global community. Although tremendous efforts are pitching in from across the globe to understand this disease, the clinical features seemed to have a wide range including fever, cough, and fatigue are the prominent features. Congestion, rhinorrhea, sore throat, and diarrhea are other less common features observed. The challenge of this disease lies in the difficulty in maneuvering the clinical course causing severe complications. One of the major causative factors for multi-organ failure in patients with severe COVID-19 complications is systemic vasculitis and cytokine-mediated coagulation disorders. Hence, effective markers trailing the disease severity and disease prognosis are urgently required for prompt medical treatment. In this review article, we have emphasized currently identified inflammatory, hematological, immunological, and biochemical biomarkers of COVID-19. We also discussed currently available biosensors for the detection of COVID-19-associated biomarkers & risk factors and the detection methods as well as their performances. These could be effective tools for rapid and more promising diagnoses in the current pandemic situation. Effective biomarkers and their rapid, scalable, & sensitive detection might be beneficial for the prevention of serious complications and the clinical management of the disease.

Angiopoietin-like 4 interacts with matrix proteins to modulate wound healing.

A dynamic cell-matrix interaction is crucial for a rapid cellular response to changes in the environment. Appropriate cell behavior in response to the changing wound environment is required for efficient wound closure. However, the way in which wound keratinocytes modify the wound environment to coordinate with such cellular responses remains less studied. We demonstrated that angiopoietin-like 4 (ANGPTL4) produced by wound keratinocytes coordinates cell-matrix communication. ANGPTL4 interacts with vitronectin and fibronectin in the wound bed, delaying their proteolytic degradation by metalloproteinases. This interaction does not interfere with integrin-matrix protein recognition and directly affects cell-matrix communication by altering the availability of intact matrix proteins. These interactions stimulate integrin- focal adhesion kinase, 14-3-3, and PKC-mediated signaling pathways essential for effective wound healing. The deficiency of ANGPTL4 in mice delays wound re-epithelialization. Further analysis revealed that cell migration was impaired in the ANGPTL4-deficient keratinocytes. Altogether, the findings provide molecular insight into a novel control of wound healing via ANGPTL4-dependent regulation of cell-matrix communication. Given the known role of ANGPTL4 in glucose and lipid homeostasis, it is a prime therapeutic candidate for the treatment of diabetic wounds. It also underscores the importance of cell-matrix communication during angiogenesis and cancer metastasis.

Angiopoietin-like 4 interacts with integrins beta1 and beta5 to modulate keratinocyte migration.

Adipose tissue secretes adipocytokines for energy homeostasis, but recent evidence indicates that some adipocytokines also have a profound local impact on wound healing. Upon skin injury, keratinocytes use various signaling molecules to promote reepithelialization for efficient wound closure. In this study, we identify a novel function of adipocytokine angiopoietin-like 4 (ANGPTL4) in keratinocytes during wound healing through the control of both integrin-mediated signaling and internalization. Using two different in vivo models based on topical immuno-neutralization of ANGPTL4 as well as ablation of the ANGPTL4 gene, we show that ANGPTL4-deficient mice exhibit delayed wound reepithelialization with impaired keratinocyte migration. Human keratinocytes in which endogenous ANGPTL4 expression was suppressed by either siRNA or a neutralizing antibody show impaired migration associated with diminished integrin-mediated signaling. Importantly, we identify integrins ß1 and ß5, but not ß3, as novel binding partners of ANGPTL4. ANGPTL4-bound integrin ß1 activated the FAK-Src-PAK1 signaling pathway, which is important for cell migration. The findings presented herein reveal an unpredicted role of ANGPTL4 during wound healing and demonstrate how ANGPTL4 stimulates intracellular signaling mechanisms to coordinate cellular behavior. Our findings provide insight into a novel cell migration control mechanism and underscore the physiological importance of the modulation of integrin activity in cancer metastasis.

Micropatterned matrix directs differentiation of human mesenchymal stem cells towards myocardial lineage.

Stem cell response can be influenced by a multitude of chemical, topological and mechanical physiochemical cues. While extensive studies have been focused on the use of soluble factors to direct stem cell differentiation, there are growing evidences illustrating the potential to modulate stem cell differentiation via precise engineering of cell shape. Fibronectin were printed on poly(lactic-co-glycolic acid) (PLGA) thin film forming spatially defined geometries as a means to control the morphology of bone marrow derived human mesenchymal stem cells (hMSCs). hMSCs that were cultured on unpatterned substrata adhered and flattened extensively (approximately 10,000 microm(2)) while cells grown on 20 microm micropatterend wide adhesive strips were highly elongated with much smaller area coverage of approximately 2000 microm(2). Gene expression analysis revealed up-regulation of several hallmark markers associated to neurogenesis and myogenesis for cells that were highly elongated while osteogenic markers were specifically down-regulated or remained at its nominal level. Even though there is clearly upregulated levels of both neuronal and myogenic lineages but at the functionally relevant level of protein expression, the myogenic lineage is dominant within the time scale studied as determined by the exclusive expression of cardiac myosin heavy chain for the micropatterned cells. Enforced cell shape distortion resulting in large scale rearrangement of cytoskeletal network and altered nucleus shape has been proposed as a physical impetus by which mechanical deformation is translated into biochemical response. These results demonstrated for the first time that cellular shape modulation in the absence of any induction factors may be a viable strategy to coax lineage-specific differentiation of stem cells.

Cytotoxic and apoptosis-inducing effects of novel 8-amido isocoumarin derivatives against breast cancer cells.

Isocoumarin is a lactone, a type of natural organic compound that is used as synthetic intermediates of several natural products and pharmaceutical compounds explored for their potential therapeutic applications like antifungal, antimicrobial, anti-inflammatory, and anticancer activities. In our previous work, we were the first group to report the use of amide C-N bond of isatins as the oxidizing directing group for the synthesis of 8-amido isocoumarin derivatives. Whereas in our present work, we have screened the cytotoxic effects of novel 8-amido isocoumarin derivatives (S1-S10) in human breast cancer MCF-7 and MDA-MB-231 cells. Our novel results revealed that N-(3-(4-methoxyphenyl)-1-oxo-4-(4-propylphenyl)-1H-isochromen-8yl)acetamide (S1) and N-(4-(3,5-difluorophenyl)-1-oxo-3-(p-tolyl)-1H-isochromen-8-yl) acetamide (S2) are the two potent compounds among the rest synthesized isocoumarin derivatives that are cytotoxic against MCF-7 and MDA-MB-231 cells, whereas less toxic to the non-tumorigenic IOSE-364 cells. Flow cytometry studies have confirmed the induction of apoptotic effects of compounds by Annexin V/PI double staining. We also observed the cytotoxic effects of S1 and S2, as evaluated by DAPI-PI immunostaining and H&E staining. The morphological alterations consistent with apoptotic blebs were observed in both cancer cells treated with compounds assessed by scanning electron microscopy. Overall, this present study strongly demonstrates that 8-amido isocoumarin derivatives have potent cytotoxic and apoptotic effects in breast cancer cells.