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1.
iScience ; 26(12): 108395, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38047085

RESUMO

Triple-negative breast cancer (TNBC) is the most elusive subtype of breast cancer that encounters treatment dilemmas owing to the paucity of druggable targets. We found hyperactivation of c-MET and ephrin type-A receptor 2 (EphA2) in patients treated with 5FU driven chemotherapy which correlated with lower disease-free survival. However, silencing of both these genes resulted in a marked decrease in the invasive, migratory, and tumorigenic potential of TNBC cells, indicating that a dual target strategy is actionable. Lupeol is a phytochemical, with potent anticancer efficacy and minimal side effects in preclinical studies. A synergistic strategy with 5FU and Lupeol elicited promising anticancer responses in vitro, in vivo, and in patient-derived ex vivo tumor culture models. This synergistic regimen is effective, even in the presence of HGF, which mechanistically orchestrates the activation of c-MET and EphA2. These data lay the foundation for the clinical validation of this combination therapy for TNBC patients.

2.
Anal Methods ; 15(22): 2745-2754, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-37248997

RESUMO

A diversified biphenyl thiosemicarbazide based chemosensor (HBMC) has been fabricated and reported for the specific detection of Cd2+ in a MeOH : H2O (4 : 1) solution. We observed a chromogenic change from colorless to light yellow colour, and it showed a "turn-on" fluorogenic change from non fluorescent to blooming cyan colour. In fluorometric titration a sharp "turn-on" emission for Cd2+ was observed with a ∼16 fold increase in fluorescence intensity value at 496 nm by incremental addition of Cd2+ ions in the MeOH : H2O (4 : 1) solution. The reversibility of the chemosensor (HBMC) was confirmed by a sequential addition of the EDTA solution. Again the binding stoichiometry of HBMC with Cd2+ was found to be 2 : 1, as confirmed by Job's plot analysis and HRMS spectra of the HBMC-Cd2+ complex. The mechanism for Cd2+ sensing in MeOH : H2O (4 : 1) is based upon the inhibition of CN isomerization and ESIPT process and simultaneously turning on the CHEF (chelation enhanced fluorescence) process. The limit of detection for Cd2+ was found to be in the order of 10-8 (M), which implies that HBMC is an efficient probe to detect Cd2+ at the microscopic level. A reusability study was performed and on-sight detection of cadmium ions by the chemosensor (HBMC) was established by dip-stick experiment. In vitro detection of Cd2+ in human breast cancer cells (MDA-MB-231) by HBMC discloses its cell permeability and biocompatible nature. Computational studies (DFT and TDDFT) with the probe HBMC and HBMC-Cd2+ complex were also performed.


Assuntos
Cádmio , Humanos , Cádmio/análise , Espectrometria de Fluorescência/métodos , Íons
3.
J Fluoresc ; 33(6): 2403-2414, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37084063

RESUMO

A new coumarin based fluorescent switch PCEH is fabricated which displays high selective sensing towards Al3+ among other metal cations at physiological pH. On gradual addition of Al3+, PCEH shows a brilliant "turn-on" emission enhancement in MeOH/H2O (4/1, v/v) solution. This new fluorescent switch is proven to be a reversible probe by gradual addition of F- into the PCEH-Al3+ solution. Detection limit as well as binding constant values are calculated to be in the order of 10-9 M and 104 M-1 respectively. We have also explored its potential as a biomarker in the application of live cell imaging using breast cancer cells (MDA-MB-231 cell).


Assuntos
Alumínio , Corantes Fluorescentes , Alumínio/metabolismo , Cátions , Microscopia de Fluorescência/métodos , Cumarínicos , Espectrometria de Fluorescência/métodos
4.
J Cell Commun Signal ; 17(3): 591-608, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36063341

RESUMO

Vasculogenic mimicry (VM), defined as an endothelial cell independent alternative mechanism of blood and nutrient supply by dysregulated tumor cells, is associated with poor prognosis in oral squamous cell carcinoma (OSCC). Here we aim to investigate the underlying molecular mechanism of the synergistic effect of phytochemical Lupeol and standard microtubule inhibitor Paclitaxel in reversing the hypoxia induced VM formation in OSCC. The results demonstrated that the hypoxia induced upregulation of HIF-1α led to augmentation of signaling cascade associated with extracellular matrix remodeling and EMT phenotypes that are mechanistically linked to VM. Induction of HIF-1α altered the expression of EMT/CSC markers (E-Cadherin, Vimentin, Snail, Twist and CD133) and enhanced the ability of cell migration/invasion and spheroid formation. Subsequently, the targeted knockdown of HIF-1α by siRNA led to the perturbation of matrigel mediated tube formation as well as of Laminin-5γ2 expression with the down-regulation of VE-Cadherin, total and phosphorylated (S-897) EphA2, pERK1/2 and MMP2. We also observed that Lupeol in association with Paclitaxel resulted to apoptosis and the disruption of VM associated phenotypes in vitro. We further validated the impact of this novel interventional approach in a patient derived tumor explant culture model of oral malignancy. The ex vivo tumor model mimicked the in vitro anti-VM potential of Lupeol-Paclitaxel combination through down-regulating HIF-1α/EphA2/Laminin-5γ2 cascade. Together, our findings elucidated mechanistic underpinning of hypoxia induced Laminin-5γ2 driven VM formation highlighting that Lupeol-Paclitaxel combination may serve as novel therapeutic intervention in perturbation of VM in human OSCC.

5.
Int J Exp Pathol ; 103(2): 54-64, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35170826

RESUMO

Vasculogenic mimicry (VM), an endothelial cell-independent alternative mechanism of blood supply to the malignant tumour, has long been considered as an adverse prognostic factor in many cancers. The correlation of VM with laminin-5γ2 and the assessment of their harmonized expression as an independent risk factor have not been elucidated yet in oral squamous cell carcinoma (OSCC). CD31/PAS staining stratified 116 clinically diagnosed OSCC specimens into VM+ and VM- cohorts. The expression pattern of laminin-5γ2 and its upstream modulator MMP2 was evaluated by immunohistochemistry and Western blot. The Kaplan-Meier and Cox regression analyses were performed to assess the survival and prognostic implications. The presence of VM demonstrated a significant correlation with the expression of laminin-5γ2 (p < .001) and MMP2 (p < .001). This pattern was mirrored by the significant upregulation of laminin-5γ2 and MMP2 in VM+ cohorts compared with the VM- ones. Furthermore, co-expression of VM and laminin-5γ2 was significantly associated with tumour grade (p = .010), primary tumour size (p < .001), lymph node metastasis (p = .001) and TNM stages (p < .001) but not with patients' age, gender, tobacco and alcohol consumption habit. Vasculogenic mimicry and laminin-5γ2 double-positive cohort displayed a significantly poorer disease-free survival (DFS) and overall survival (OS). Vasculogenic mimicry, laminin-5γ2 and their subsequent dual expression underlie a significant prognostic value for DFS [hazard ratio (HR) = 9.896, p = .028] and OS [HR = 21.401, p = .033] in OSCC patients. Together, our findings imply that VM along with laminin-5γ2 is strongly linked to the malignant progression in OSCC and VM and laminin-5γ2 coordination emerges as a critical prognostic biomarker for OSCC.


Assuntos
Laminina , Neoplasias Bucais , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Laminina/metabolismo , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Neovascularização Patológica/metabolismo , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia
6.
Breast Cancer Res Treat ; 179(2): 359-370, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31686261

RESUMO

PURPOSE: The occurrence of vasculogenic mimicry (VM) and EphA2-mediated tumour progression are associated with poor prognosis in various solid tumours. Here, we aimed to investigate the prognostic implications of VM and its association with phosphorylated EphA2 receptor in invasive carcinoma of the breast. METHODS: The patients were stratified based on CD-31/PAS dual staining and subsequently the expression status of phospho-EphA2 (S897), FAK, phospho-ERK1/2 and Laminin 5Ƴ2 was analysed by immunohistochemistry. Survival of patients was correlated within the stratified cohort. RESULTS: The pathologically defined VM phenotype and phospho-EphA2 (S897) expression status were significantly associated with lower disease-free survival (DFS) and overall survival (OS). Both the features were also found to be significantly associated with higher nodal status, poor Nottingham Prognostic Index (NPI) and were more prevalent in the triple-negative breast cancer (TNBC) group. Incidentally, there were no significant association between age of the patient, grade and size of the tumour with VM and phospho-EphA2 (S897). The effector molecules of phospho-EphA2 (S897) viz., Focal Adhesion Kinase (FAK), phospho-ERK1/2 and Laminin 5Ƴ2 were significantly upregulated in the VM-positive cohort. Survival analysis revealed that the VM and phospho-EphA2 (S897) dual-positive cohort had poorest DFS [mean time = 48.313 (39.992-56.633) months] and OS [mean time = 56.692 (49.055-64.328) months]. Individually, VM-positive [Hazard Ratio (HR) 6.005; 95% confidence interval (CI) 2.002-18.018; P = 0.001 for DFS and HR 11.654; 95% CI 3.195-42.508; P < 0.0001 for OS] and phospho-EphA2 (S897)-positive (HR 4.342; 95% CI 1.717-10.983; P = 0.002 for DFS and HR 5.853; 95% CI 1.663-20.602; P = 0.006 for OS) expression proved to be independent indicators of prognosis. CONCLUSION: This study evaluated tumour dependency on oncogenic EphA2 receptor regulation and VM in invasive carcinoma of the breast and their prognostic significance. Significant correlations between VM, phospho-EphA2 and several clinicopathologic parameters of breast cancer were found. Subsequently, the occurrence of VM or phospho-EphA2 expression proved to be major contributors for poor prognosis in patients with breast cancer but their simultaneous expression failed to be an independent risk factor.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neovascularização Patológica/metabolismo , Receptor EphA2/metabolismo , Adulto , Idoso , Biomarcadores Tumorais , Neoplasias da Mama/etiologia , Neoplasias da Mama/mortalidade , Linhagem Celular Tumoral , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fosforilação , Prognóstico , Modelos de Riscos Proporcionais , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia
7.
Microvasc Res ; 121: 52-62, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30381268

RESUMO

Vasculogenic mimicry, an endothelia-independent tumor microcirculation has been found in various cancers and is thought to be achieved by cancer stem like cells. Dacarbazine resistance is one of the most common features of melanoma and recent studies suggest that the mode of resistance is closely related to the formation of vasculogenic mimicry. In our work, we examined the anticancer effect of Lupeol, a novel phytochemical with Dacarbazine in vivo and in vitro. Results demonstrated adequate cytotoxicity followed by down regulation of CD 133 expression in Lupeol treated B16-F10 cell line. In solid tumor model the drug also inhibited vasculogenic mimicry along with angiogenesis by altering both the cancer stem cell as well as the endothelial progenitor cell population. Lupeol hindered the maturation of bone marrow derived endothelial progenitors and thus, retarded the formation of rudimentary tumor microvessels. Notably, Dacarbazine treatment demonstrated unresponsiveness to B16-F10 cells in both in vivo and in vitro model via upregulation of CD 133 expression and increased formation of vasculogenic mimicry tubes. Together, these data indicate that Lupeol alone can become a proficient agent in treating melanoma, inhibiting vasculogenic mimicry and might play a significant role in subduing Dacarbazine induced drug resistance.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Mimetismo Biológico , Progressão da Doença , Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/tratamento farmacológico , Triterpenos Pentacíclicos/farmacologia , Antígeno AC133/metabolismo , Animais , Antígenos CD/metabolismo , Antineoplásicos Alquilantes/farmacologia , Caderinas/metabolismo , Dacarbazina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Células Progenitoras Endoteliais/efeitos dos fármacos , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Masculino , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Neovascularização Patológica , Fenótipo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Carga Tumoral/efeitos dos fármacos
8.
Curr Mol Med ; 18(7): 459-474, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30539699

RESUMO

BACKGROUND: Madhuca indica belongs to the family sapotaceae, commonly known as Mahua. It is primarily known for alcoholic beverage production and is reported to have anti-inflammatory, analgesic and antipyretic properties. Madhuca indica has also been reported to be effective in several diseases. OBJECTIVE: This study was undertaken to check the anticancer efficacy and chemopreventive effect of methanolic extract of Mahua flower (ME) on human breast cancer cell lines MCF-7 and MDA-MB-468. METHOD: The cytotoxic and anti-proliferative effects on MCF-7 and MDA-MB-468 cells were studied by MTT, hexosaminidase and colony formation assay. Expression of caspase 3/7 was assessed by flow cytometry and western blot analysis. Expression of COX-2 was evaluated by western blot analysis, luciferase assay and mRNA analysis. RESULTS: ME inhibited the proliferation of breast cancer cells by inducing apoptosis through up-regulating the expression of Caspase 3/7 (P < 0.0001). Our results showed a decrease in the expression of COX-2 mRNA and COX-2 protein in both MCF-7 and MDA-MB-468 cells with an increase in ME concentration. Furthermore synergistic effect of ME and chemotherapeutic drug paclitaxel was also studied in MCF-7 and MDA-MB- 468 cells which were found to be more effective (P < 0.0001) than treatment of either ME or paclitaxel alone. Results were analyzed by ANOVA and Pearson correlation analysis. CONCLUSION: All these experiments suggest that ME inhibits breast cancer cell proliferation and apoptosis by inhibiting the expression of COX-2 in MCF-7 and MDAMB- 468 cells. This work further highlighted that ME may enhance the potentiality of paclitaxel in breast cancer treatment.


Assuntos
Neoplasias da Mama/enzimologia , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/biossíntese , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Madhuca/química , Proteínas de Neoplasias/biossíntese , Extratos Vegetais/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Feminino , Humanos , Células MCF-7 , Extratos Vegetais/química
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