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1.
Mol Cancer ; 23(1): 121, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38853277

RESUMO

BACKGROUND: Platinum resistance is the primary cause of poor survival in ovarian cancer (OC) patients. Targeted therapies and biomarkers of chemoresistance are critical for the treatment of OC patients. Our previous studies identified cell surface CD55, a member of the complement regulatory proteins, drives chemoresistance and maintenance of cancer stem cells (CSCs). CSCs are implicated in tumor recurrence and metastasis in multiple cancers. METHODS: Protein localization assays including immunofluorescence and subcellular fractionation were used to identify CD55 at the cell surface and nucleus of cancer cells. Protein half-life determinations were used to compare cell surface and nuclear CD55 stability. CD55 deletion mutants were generated and introduced into cancer cells to identify the nuclear trafficking code, cisplatin sensitivity, and stem cell frequency that were assayed using in vitro and in vivo models. Detection of CD55 binding proteins was analyzed by immunoprecipitation followed by mass spectrometry. Target pathways activated by CD55 were identified by RNA sequencing. RESULTS: CD55 localizes to the nucleus of a subset of OC specimens, ascites from chemoresistant patients, and enriched in chemoresistant OC cells. We determined that nuclear CD55 is glycosylated and derived from the cell surface pool of CD55. Nuclear localization is driven by a trafficking code containing the serine/threonine (S/T) domain of CD55. Nuclear CD55 is necessary for cisplatin resistance, stemness, and cell proliferation in OC cells. CD55 S/T domain is necessary for nuclear entry and inducing chemoresistance to cisplatin in both in vitro and in vivo models. Deletion of the CD55 S/T domain is sufficient to sensitize chemoresistant OC cells to cisplatin. In the nucleus, CD55 binds and attenuates the epigenetic regulator and tumor suppressor ZMYND8 with a parallel increase in H3K27 trimethylation and members of the Polycomb Repressive Complex 2. CONCLUSIONS: For the first time, we show CD55 localizes to the nucleus in OC and promotes CSC and chemoresistance. Our studies identify a therapeutic mechanism for treating platinum resistant ovarian cancer by blocking CD55 nuclear entry.


Assuntos
Antígenos CD55 , Núcleo Celular , Cromatina , Cisplatino , Resistencia a Medicamentos Antineoplásicos , Histonas , Células-Tronco Neoplásicas , Neoplasias Ovarianas , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/genética , Feminino , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Animais , Camundongos , Antígenos CD55/metabolismo , Antígenos CD55/genética , Linhagem Celular Tumoral , Histonas/metabolismo , Núcleo Celular/metabolismo , Cromatina/metabolismo , Metilação , Ensaios Antitumorais Modelo de Xenoenxerto , Antineoplásicos/farmacologia , Transporte Proteico
2.
Br J Cancer ; 118(11): 1442-1452, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29695771

RESUMO

BACKGROUND: Monoamine oxidases (MAO) are mitochondrial enzymes functioning in oxidative metabolism of monoamines. The action of MAO-A has been typically described in neuro-pharmacological domains. Here, we have established a co-relation between IL-6/IL-6R and MAO-A and their regulation in hypoxia induced invasion/angiogenesis. METHODS: We employed various in-vitro and in-vivo techniques and clinical samples. RESULTS: We studied a co-relation among MAO-A and IL-6/IL-6R and tumour angiogenesis/invasion in hypoxic environment in breast cancer model. Activation of IL-6/IL-6R and its downstream was found in hypoxic cancer cells. This elevation of IL-6/IL-6R caused sustained inhibition of MAO-A in hypoxic environment. Inhibition of IL-6R signalling or IL-6R siRNA increased MAO-A activity and inhibited tumour angiogenesis and invasion significantly in different models. Further, elevation of MAO-A with 5-azacytidine (5-Aza) modulated IL-6 mediated angiogenesis and invasive signatures including VEGF, MMPs and EMT in hypoxic breast cancer. High grade invasive ductal carcinoma (IDC) clinical specimen displayed elevated level of IL-6R and depleted MAO-A expression. Expression of VEGF and HIF-1α was unregulated and loss of E-Cadherin was observed in high grade IDC tissue specimen. CONCLUSIONS: Suppression of MAO-A by IL-6/IL-6R activation promotes tumour angiogenesis and invasion in hypoxic breast cancer environment.


Assuntos
Neoplasias da Mama/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Interleucina-6/metabolismo , Monoaminoxidase/metabolismo , Receptores de Interleucina-6/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Antígenos CD/metabolismo , Azacitidina/farmacologia , Neoplasias da Mama/irrigação sanguínea , Caderinas/metabolismo , Hipóxia Celular , Linhagem Celular Tumoral , Embrião de Galinha , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Modelos Biológicos , Invasividade Neoplásica
3.
Acta Pharmacol Sin ; 38(5): 591-613, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28317871

RESUMO

Glioma accounts for the majority of human brain tumors. With prevailing treatment regimens, the patients have poor survival rates. In spite of current development in mainstream glioma therapy, a cure for glioma appears to be out of reach. The infiltrative nature of glioma and acquired resistance substancially restrict the therapeutic options. Better elucidation of the complicated pathobiology of glioma and proteogenomic characterization might eventually open novel avenues for the design of more sophisticated and effective combination regimens. This could be accomplished by individually tailoring progressive neuroimaging techniques, terminating DNA synthesis with prodrug-activating genes, silencing gliomagenesis genes (gene therapy), targeting miRNA oncogenic activity (miRNA-mRNA interaction), combining Hedgehog-Gli/Akt inhibitors with stem cell therapy, employing tumor lysates as antigen sources for efficient depletion of tumor-specific cancer stem cells by cytotoxic T lymphocytes (dendritic cell vaccination), adoptive transfer of chimeric antigen receptor-modified T cells, and combining immune checkpoint inhibitors with conventional therapeutic modalities. Thus, the present review captures the latest trends associated with the molecular mechanisms involved in glial tumorigenesis as well as the limitations of surgery, radiation and chemotherapy. In this article we also critically discuss the next generation molecular therapeutic strategies and their mechanisms for the successful treatment of glioma.


Assuntos
Neoplasias Encefálicas/terapia , Encéfalo/patologia , Glioma/terapia , Terapia de Alvo Molecular/tendências , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Carcinogênese/genética , Carcinogênese/patologia , Glioma/genética , Glioma/patologia , Humanos , Terapia de Alvo Molecular/métodos
4.
Microvasc Res ; 107: 6-16, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27131831

RESUMO

Laser speckle contrast imaging (LSCI) provides a noninvasive and cost effective solution for in vivo monitoring of blood flow. So far, most of the researches consider changes in speckle pattern (i.e. correlation time of speckle intensity fluctuation), account for relative change in blood flow during abnormal conditions. This paper introduces an application of LSCI for monitoring wound progression and characterization of cutaneous wound regions on mice model. Speckle images are captured on a tumor wound region at mice leg in periodic interval. Initially, raw speckle images are converted to their corresponding contrast images. Functional characterization begins with first segmenting the affected area using k-means clustering, taking wavelet energies in a local region as feature set. In the next stage, different regions in wound bed are clustered based on progressive and non-progressive nature of tissue properties. Changes in contrast due to heterogeneity in tissue structure and functionality are modeled using LSCI speckle statistics. Final characterization is achieved through supervised learning of these speckle statistics using support vector machine. On cross evaluation with mice model experiment, the proposed approach classifies the progressive and non-progressive wound regions with an average sensitivity of 96.18%, 97.62% and average specificity of 97.24%, 96.42% respectively. The clinical information yield with this approach is validated with the conventional immunohistochemistry result of wound to justify the ability of LSCI for in vivo, noninvasive and periodic assessment of wounds.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Fluxometria por Laser-Doppler/métodos , Microcirculação , Imagem de Perfusão/métodos , Sarcoma 180/irrigação sanguínea , Sarcoma 180/diagnóstico por imagem , Pele/irrigação sanguínea , Aprendizado de Máquina Supervisionado , Animais , Área Sob a Curva , Velocidade do Fluxo Sanguíneo , Interpretação Estatística de Dados , Modelos Animais de Doenças , Imuno-Histoquímica , Fluxometria por Laser-Doppler/estatística & dados numéricos , Masculino , Camundongos , Imagem de Perfusão/estatística & dados numéricos , Valor Preditivo dos Testes , Curva ROC , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Sarcoma 180/patologia , Pele/patologia , Fatores de Tempo , Cicatrização
6.
Tumour Biol ; 36(12): 9829-37, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26159854

RESUMO

Despite the recent advances in diagnostic and therapeutic strategies, oral squamous cell carcinoma (OSCC) remains a major health burden. Protein biomarker discovery for early detection will help to improve patient survival rate in OSCC. Mass spectrometry-based proteomics has emerged as an excellent approach for detection of protein biomarkers in various types of cancers. In the current study, we have used 4-Plex isobaric tags for relative and absolute quantitation (iTRAQ)-based shotgun quantitative proteomic approach to identify proteins that are differentially expressed in cancerous tissues compared to normal tissues. The high-resolution mass spectrometric analysis resulted in identifying 2,074 proteins, among which 288 proteins were differentially expressed. Further, it was noticed that 162 proteins were upregulated, while 125 proteins were downregulated in OSCC-derived cancer tissue samples as compared to the adjacent normal tissues. We identified some of the known molecules which were reported earlier in OSCC such as MMP-9 (8.4-fold), ZNF142 (5.6-fold), and S100A7 (3.5-fold). Apart from this, we have also identified some novel signature proteins which have not been reported earlier in OSCC including ras-related protein Rab-2A isoform, RAB2A (4.6-fold), and peroxiredoxin-1, PRDX1 (2.2-fold). The immunohistochemistry-based validation using tissue microarray slides in OSCC revealed overexpression of the RAB2A and PRDX1 gene in 80 and 68 % of the tested clinical cases, respectively. This study will not only serve as a resource of candidate biomarkers but will contribute towards the existing knowledge on the role of the candidate molecules towards disease progression and therapeutic potential.


Assuntos
Biomarcadores Tumorais/biossíntese , Carcinoma de Células Escamosas/genética , Neoplasias Bucais/genética , Peroxirredoxinas/biossíntese , Proteínas rab de Ligação ao GTP/biossíntese , Idoso , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Peroxirredoxinas/genética , Proteoma/genética , Proteômica , Espectrometria de Massas em Tandem , Proteínas rab de Ligação ao GTP/genética
8.
Cancer Cell Int ; 15: 74, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26225121

RESUMO

BACKGROUND: Squamous cell carcinoma of the oral cavity (SCCOC) is the dominant origin of cancer associated mortality. Previous findings by our study reported that acquisition of anoikis resistance has a significant role in tumor progression of oral cavity. Several genes were over-expressed in anoikis-resistant cells under detached conditions which we confirmed earlier by microarray. Normal oral squamous epithelia grow adherent to a basement membrane, and when detached from the extracellular matrix, undergoes programmed cell death. The acquisition of anoikis-resistance is crucial phenomena in oral tumor advancement. In the current study, we have identified S100A7 expression as contributing factor for anoikis resistance and tumorigenicity in human oral cancer cells. Further, we have explored that elevated S100A7 expression in anoikis-sensitive oral keratinocytes and cancer cells reshape them more resistant to anoikis and apoptosis inducers via activation of cellular intrinsic and extrinsic avenue. METHODS: A subset of human cancer cell lines TU167, JMAR, JMARC39, JMARC42 and MDA-MB-468 were utilized for the generation of resistant stable cell lines. Further, immunohistochemistry, western blot and immunoprecipitation, assays of apoptosis, soft agar assay, orthotopic animal model and signaling elucidation were performed to establish our hypothesis. RESULTS: S100A7 gene is found to be responsible for anoikis resistance and tumorigenicity in human oral cancer cells. We have observed up-regulation of S100A7 in anoikis resistant cell lines, orthotropic model and patients samples with head and neck cancer. It is also noticed that secretion of S100A7 protein in conditioned medium by anoikis resistant head & neck cancer cell and in saliva of head and neck cancer patients. Up-regulation of S100A7 expression has triggered enhanced tumorigenicity and anchorage-independent growth of cancer cells through Akt phosphorylation leading to development of aniokis resistance in head and neck cancer cells. CONCLUSIONS: These data have led us to conclude that S100A7 is the major contributing factor in mediating anoikis-resistance of oral cancer cells and local tumor progression, and S100A7 might be useful as diagnostic marker for early detection of primary and recurrent squamous cell cancer.

9.
Mol Pharm ; 12(12): 4214-25, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26505213

RESUMO

Akt overexpression in cancer causes resistance to traditional chemotherapeutics. Silencing Akt through siRNA provides new therapeutic options; however, poor in vivo siRNA pharmacokinetics impede translation. We demonstrate that acidic milieu-sensitive multilamellar gold niosomes (Nio-Au) permit targeted delivery of both Akt-siRNA and thymoquinone (TQ) in tamoxifen-resistant and Akt-overexpressing MCF7 breast cancer cells. Octadecylamine groups of functionalized gold nanoparticles impart cationic attribute to niosomes, stabilized through polyethylene glycol. TQ's aqueous insolubility renders its encapsulation within hydrophobic core, and negatively charged siRNA binds in hydrophilic region of cationic niosomes. These niosomes were exploited to effectively knockdown Akt, thereby sensitizing cells to TQ. Immunoblot studies revealed enhanced apoptosis by inducing p53 and inhibiting MDM2 expression, which was consistent with in vivo xenograft studies. This innovative strategy, using Nio-Au to simultaneously deliver siRNA (devoid of any chemical modification) and therapeutic drug, provides an efficacious approach for treating therapy-resistant cancers with significant translational potential.


Assuntos
Benzoquinonas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ouro/administração & dosagem , Nanopartículas/administração & dosagem , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/genética , Apoptose/efeitos dos fármacos , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Feminino , Humanos , Células MCF-7 , Tamoxifeno/farmacologia
10.
J Ovarian Res ; 16(1): 122, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37370140

RESUMO

Poly-ADP Ribose Polymerase (PARP) targeted therapy is clinically approved for the treatment of homologous recombination (HR) repair deficient tumors. The remarkable success of this therapy in the treatment of HR repair deficient cancers has not translated to HR-proficient cancers. Our studies identify the novel role of non-receptor lymphocyte-specific protein tyrosine kinase (LCK) in the regulation of HR repair in endometrioid epithelial ovarian cancer (eEOC) model. We show that DNA damage leads to direct interaction of LCK with the HR repair proteins RAD51 and BRCA1 in a kinase dependent manner RAD51 and BRCA1 stabilization. LCK expression is induced and activated in the nucleus in response to DNA damage insult. Disruption of LCK expression attenuates RAD51, BRCA1, and BRCA2 protein expression by hampering there stability and results in inhibition of HR-mediated DNA repair including suppression of RAD51 foci formation, and augmentation of γH2AX foci formation. In contrast LCK overexpression leads to increased RAD51 and BRCA1 expression with a concomitant increase in HR DNA damage repair. Importantly, attenuation of LCK sensitizes HR-proficient eEOC cells to PARP inhibitor in cells and pre-clinical mouse studies. Collectively, our findings identify a novel therapeutic strategy to expand the utility of PARP targeted therapy in HR proficient ovarian cancer.


Assuntos
Carcinoma Endometrioide , Neoplasias Ovarianas , Animais , Feminino , Humanos , Camundongos , Proteína BRCA1/genética , Carcinoma Endometrioide/tratamento farmacológico , Carcinoma Epitelial do Ovário/tratamento farmacológico , Linhagem Celular Tumoral , Dano ao DNA , Reparo do DNA , Recombinação Homóloga , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo
11.
Cancer Lett ; 551: 215935, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36216147

RESUMO

CD55, or decay accelerating factor, is a membrane lipid microdomain-associated, GPI-anchored protein implicated in the shielding of cells from complement-mediated attack via accelerating decay of C3 and C5. Loss of CD55 is associated with a number of pathologies due to hyperactivation of the complement system. CD55 is also implicated in cancer progression thought to be driven via its role in cell shielding mechanisms. We now appreciate that CD55 can signal intracellularly to promote malignant transformation, cancer progression, cell survival, angiogenesis, and inhibition of apoptosis. Outside-in signaling via CD55 is mediated by signaling pathways including JNK, JAK/STAT, MAPK/NF-κB, and LCK. Moreover, CD55 is enriched in the cancer stem cell (CSC) niche of multiple tumors including breast, ovarian, cervical, and can be induced by chemotherapeutics and hypoxic environments. CSCs are implicated in tumor recurrence and chemoresistance. Here, we review the unexpected roles of CD55 in cancer including the roles of canonical and noncanonical pathways that CD55 orchestrates. We will highlight opportunities for therapeutic targeting CD55 and gaps in the field that require more in-depth mechanistic insights.

12.
Acta Pol Pharm ; 68(2): 155-60, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21485287

RESUMO

This study describes development and subsequent validation of a reversed phase high performance liquid chromatographic (RP-HPLC) method for the estimation of nandrolone phenylpropionate, an anabolic steroid, in bulk drug, in conventional parenteral dosage formulation and in prepared nanoparticle dosage form. The chromatographic system consisted of a Luna Phenomenex, CN (250 mm x 4.6 mm, 5 microm) column, an isocratic mobile phase comprising 10 mM phosphate buffer and acetonitrile (50:50, v/v) and UV detection at 240 nm. Nandrolone phenylpropionate was eluted about 6.3 min with no interfering peaks of excipients used for the preparation of dosage forms. The method was linear over the range from 0.050 to 25 microg/mL in raw drug (r2 = 0.9994). The intra-day and inter-day precision values were in the range of 0.219-0.609% and 0.441-0.875%, respectively. Limits of detection and quantitation were 0.010 microg/mL and 0.050 microg/mL, respectively. The results were validated according to International Conference on Harmonization (ICH) guidelines in parenteral and prepared nanoparticle formulation. The validated HPLC method is simple, sensitive, precise, accurate and reproducible.


Assuntos
Anabolizantes/análise , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Nandrolona/análogos & derivados , Tecnologia Farmacêutica/métodos , Soluções Tampão , Química Farmacêutica , Cromatografia Líquida de Alta Pressão/normas , Cromatografia de Fase Reversa/normas , Formas de Dosagem , Composição de Medicamentos , Injeções , Nandrolona/análise , Nanopartículas , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Tecnologia Farmacêutica/normas
13.
J Ovarian Res ; 14(1): 55, 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888137

RESUMO

BACKGROUND: Ovarian cancer is the most fatal gynecologic malignancy in the United States. While chemotherapy is effective in the vast majority of ovarian cancer patients, recurrence and resistance to standard systemic therapy is nearly inevitable. We discovered that activation of the non-receptor tyrosine kinase Lymphocyte Cell-Specific Protein-Tyrosine Kinase (LCK) promoted cisplatin resistance. Here, we hypothesized that treating high grade, platinum resistant endometrioid cancer cells with an LCK inhibitor (LCKi) followed by co-treatment with cisplatin would lead to increased cisplatin efficacy. Our objective was to assess clinical outcomes associated with increased LCK expression, test our hypothesis of utilizing LCKi as pre-treatment followed by co-treatment with cisplatin in platinum resistant ovarian cancer in vitro, and evaluate our findings in vivo to assess LCKi applicability as a therapeutic agent. RESULTS: Kaplan-Meier (KM) plotter data indicated LCK expression is associated with significantly worse median progression-free survival (HR 3.19, p = 0.02), and a trend toward decreased overall survival in endometrioid ovarian tumors with elevated LCK expression (HR 2.45, p = 0.41). In vitro, cisplatin resistant ovarian endometrioid cells treated first with LCKi followed by combination LCKi-cisplatin treatment showed decreased cell viability and increased apoptosis. Immunoblot studies revealed LCKi led to increased expression of phosphorylated H2A histone family X ([Formula: see text]-H2AX), a marker for DNA damage. In vivo results demonstrate treatment with LCKi followed by LCKi-cisplatin led to significantly slowed tumor growth. CONCLUSIONS: We identified a strategy to therapeutically target cisplatin resistant endometrioid ovarian cancer leading to chemosensitization to platinum chemotherapy via treatment with LCKi followed by co-treatment with LCKi-cisplatin.


Assuntos
Carcinoma Endometrioide/tratamento farmacológico , Cisplatino/uso terapêutico , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/antagonistas & inibidores , Neoplasias Ovarianas/tratamento farmacológico , Animais , Carcinoma Endometrioide/mortalidade , Cisplatino/farmacologia , Feminino , Humanos , Camundongos , Neoplasias Ovarianas/mortalidade , Análise de Sobrevida
14.
Regul Toxicol Pharmacol ; 58(2): 196-207, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20580917

RESUMO

The purpose of this study was to investigate the potential toxicity of gemifloxacin by 28-day repeated oral dose in Wistar albino rats. The test article, was administered daily by gavage to male and female rats at dose levels of 0, 50, 100, 200 mg/kg/day. At the end of treatment period, 12 rats/sex/group was sacrificed, while six extra rats/sex in the vehicle control and highest dose groups sacrificed after 14 days recovery period. During the treatment and recovery periods, clinical signs, mortality, body weights, food and water consumption, ophthalmoscopy, urinalysis, phototoxicity, hematology, serum biochemistry, synovial fluid biochemistry, electrocardiogram (ECG), gross findings, organ weights, microscopic examination of synovial fluid, and histopathology were examined. Hematological and serum biochemical investigations revealed a dose-dependent increase in the total white blood cell (WBC), total bilirubin (T-BIL), glucose (GLU), alanine aminotransferase (ALT) and significant decreases in total protein (TP) were observed in both sexes at the same dose, at the end of treatment period, but the levels returned toward normal during the recovery period. Histopathology of talar joint showed that erosion of the articular surface of that joint in both sexes at the end of treatment period at the dose level of 200 mg/kg/day. Degenerative changes in tendinocytes were observed in Achilles tendon of both sexes at the high dose level at the end of treatment period. In histopathological study shows partial effacement of liver architecture and focal ulceration in gastric mucosa at the high dose level at the end of treatment period. Based on these results, it was concluded that 28 days repeated oral dose of gemifloxacin caused increases in the liver weight, WBC count, T-BIL, glucose level, ALT, decreasing the TP, cause chronic hepatitis and acute gastritis, erosion of the articular surface of joint and histopathologic changes in Achilles tendon in rats at the dose level of 200 mg/kg/day.


Assuntos
Antibacterianos/toxicidade , Fluoroquinolonas/toxicidade , Naftiridinas/toxicidade , Administração Oral , Animais , Antibacterianos/administração & dosagem , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Fluoroquinolonas/administração & dosagem , Gastrite/induzido quimicamente , Gemifloxacina , Masculino , Naftiridinas/administração & dosagem , Ratos , Ratos Wistar , Fatores Sexuais , Testes de Toxicidade
15.
J Mol Model ; 26(7): 173, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32524411

RESUMO

The keto-enol tautomerisation in homophthalic anhydride (HA) is investigated in the ground (S0) and excited (S1) electronic states. The keto form with a dicarbonyl structure is found to be the most stable form in S0 and enol form with a monocarbonyl structure in S1 indicating an excited state intramolecular proton transfer (ESIPT) process. The computed results show consistency with the change in basis sets and methods of calculations. Apart from the two tautomers, transition states are also identified. The barrier to interconversion is found to reduce substantially in S1. Internal reaction coordinate (IRC) calculations confirm the pathway of interconversion between the two forms in S0 and S1. The observed FT-IR spectra corroborate well with our computed spectra. The appearance of two strong lines around 1800 cm-1 confirms the lowest energy structure to be the keto tautomer with a dicarbonyl form in S0. Our computations corroborate well with the crystal structure data for an analogous molecule. Electron distribution in HOMO and LUMO indicate the excitation process as π → π* in nature. The qualitative chemical concepts like hardness and electrophilicity are calculated to estimate the stability of the tautomers. The energy and hardness profiles with the variation of IRC are opposite to each other, verifying the principle of maximum hardness.

16.
ACS Appl Mater Interfaces ; 11(37): 33599-33611, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31429277

RESUMO

In the present scenario, the invention of bacteria-selective antimicrobial agent comprising negligible toxicity and hemolytic effect is a great challenge. To surmount this challenge, here, a series of polypeptide nanogels (PNGs) have been fabricated by a coordination-assisted self-assembly of a mannose-conjugated antimicrobial polypeptide, poly(arginine-r-valine)-mannose (poly(Arg-r-Val)-M2), with Zn2+ ions. The fabricated PNGs are spherical in shape with a unique structural appearance similar to that of Taxus baccata fruits. PNGs, with a unique structural arrangement and threshold surface charge density, selectively interact with the bacterial membrane and exhibit potent antimicrobial activity, as reflected in their lower minimum inhibitory concentration values (varies from 2 to 16 µg/mL). PNGs show a remarkably high binding constant, 6.02 × 105 M-1 (from isothermal titration calorimetry, ITC), with the bacterial membrane which manifests its potent bactericidal effect. PNGs are nontoxic against mammalian and red blood cells as reflected from their higher cell viability and insignificant hemolytic effect. PNGs are taken up by the bacterial membrane and selectively undergo structural deformation (scrutinized by ITC) followed by an exposure of free poly(Arg-r-Val)-M2 molecules. The free poly(Arg-r-Val)-M2 molecules are enforced to lyse the bacterial membrane (visualized by cryo-transmission electron microscopy) followed by the diffusion of the cytoplasmic component out of the membrane which culminates in the final death of the bacterium.


Assuntos
Antibacterianos , Peptídeos Catiônicos Antimicrobianos , Bactérias/metabolismo , Infecções Bacterianas/tratamento farmacológico , Membrana Celular/metabolismo , Nanogéis/química , Adulto , Antibacterianos/química , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bactérias/ultraestrutura , Infecções Bacterianas/metabolismo , Membrana Celular/ultraestrutura , Feminino , Humanos , Masculino
17.
ACS Biomater Sci Eng ; 5(1): 149-164, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33405857

RESUMO

Tissue engineering has a major emphasis in creating tissue specific extracellular ambiance by altering chemical functionalities of scaffold materials. Heterogeneity of osteochondral tissue necessitates tailorable bone and cartilage specific extracellular environment. Carboxylate- and sulfate-functionalized glycosaminoglycans (GAGs) in cartilage extracellular matrix (ECM) create an acidic ambience to support chondrogenic activity, whereas phosphate-rich environment in bone enables chelation of calcium leading to the formation of mineralized matrix along with an alkaline environment to support osteogenesis. In this study, chitosan, a naturally occurring GAGs, was functionalized with phosphate/sulfate groups analogous to bone/cartilage ECM and incorporated in thermogelling agarose hydrogel for delivery to osteochondral defects. In vitro studies revealed significantly higher adhesion and proliferation of adipose derived mesenchymal stem cells (ADMSCs) with blended hydrogels as compared to that of native agarose. Cell differentiation and RT-PCR studies of the phosphorylated hydrogels revealed higher osteogenic potential, while sulfated hydrogels demonstrated enhanced chondrogenic activity in comparison to agarose. Recovery of osteochondral defects after delivery of the thermoresponsive agarose-based hydrogels decorated with phosphorylated derivatives showed significantly higher bone formation. On the other hand, cartilage formation was significant with chitosan sulfate decorated hydrogels. The study highlights the role of chitosan derivatives in osteochondral defect healing, especially phosphorylated ones as bone promoter, whereas sulfated ones act as cartilage enhancer, which was quantitatively distinguished through micro-CT-based noninvasive imaging and analysis.

18.
Biomater Sci ; 7(3): 1161-1178, 2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30652182

RESUMO

Melanoma is a highly aggressive skin cancer. A paclitaxel formulation of solid lipid nanoparticles modified with Tyr-3-octreotide (PSM) is employed to treat melanoma that highly expresses somatostatin receptors (SSTRs). PSM exerts more apoptotic and anti-invasive effects in B16F10 mice melanoma cells as compared to dacarbazine (DTIC), an approved chemotherapeutic drug for treating aggressive melanoma. Besides, PSM induces one of the biomarkers of immunogenic cell death in vitro and in vivo as confirmed by calreticulin exposure on the B16F10 cell surface. We observed a significant number of CD8 positive T cells in the tumor bed of the PSM treated group. As a result, PSM effectively reduces tumor volume in vivo as compared to DTIC. PSM also induces a favorable systemic immune response as determined in the spleen and sera of the treated animals. Importantly, PSM can reduce the number of nodule formations in the experimental lung metastasis model. Our experimentations indicate that the metronomic PSM exhibits remarkable anti-melanoma activities without any observable toxicity. This immune modulation behavior of PSM can be exploited for the therapy of melanoma and probably for other malignancies.


Assuntos
Antineoplásicos Alquilantes/química , Nanopartículas/química , Paclitaxel/química , Peptídeos/química , Animais , Antineoplásicos Alquilantes/metabolismo , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Apoptose/efeitos dos fármacos , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Calreticulina/química , Calreticulina/farmacologia , Linhagem Celular Tumoral , Citocinas/metabolismo , Dacarbazina/química , Dacarbazina/metabolismo , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , Modelos Animais de Doenças , Feminino , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/mortalidade , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Paclitaxel/metabolismo , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Taxa de Sobrevida , Distribuição Tecidual
19.
Cancer Lett ; 452: 254-263, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-30904616

RESUMO

Epithelial to mesenchymal transition (EMT) is compulsory for metastatic dissemination and is stimulated by TGF-ß. Although targeting EMT has significant therapeutic potential, very few pharmacological agents have been shown to exert anti-metastatic effects. BI-69A11, a competitive Akt inhibitor, displays anti-tumor activity toward melanoma and colon carcinoma. This study provides molecular and biochemical insights into the effects of BI-69A11 on EMT in colon carcinoma cells in vitro and in vivo. BI-69A11 inhibited metastasis-associated cellular migration, invasion and adhesion by inhibiting the Akt-ß-catenin pathway. The underlying mechanism of BI-69A11-mediated inhibition of EMT included suppression of nuclear transport of ß-catenin and diminished phosphorylation of ß-catenin, which was accompanied by enhanced E-cadherin-ß-catenin complex formation at the plasma membrane. Additionally, BI-69A11 caused increased accumulation of vinculin in the plasma membrane, which fortified focal adhesion junctions leading to inhibition of metastasis. BI-69A11 downregulated activation of the TGF-ß-induced non-canonical Akt/NF-κB pathway and blocked TGF-ß-induced enhanced expression of Snail causing restoration of E-cadherin. Overall, this study enhances our understanding of the molecular mechanism of BI-69A11-induced reversal of EMT in colorectal carcinoma cells in vitro, in vivo and in TGF-ß-induced model systems.


Assuntos
Antígenos CD/metabolismo , Antineoplásicos/farmacologia , Benzimidazóis/farmacologia , Caderinas/metabolismo , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Quinolonas/farmacologia , beta Catenina/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Humanos , Invasividade Neoplásica/patologia , Metástase Neoplásica/patologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Fator de Crescimento Transformador beta/metabolismo , Vinculina/metabolismo
20.
Int J Biol Macromol ; 112: 818-830, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29421493

RESUMO

Liver cancer is a leading cause of death related to cancer worldwide. Poly(d-l-lactide-co-glycolide) (PLGA) nanoparticles provide prolonged blood residence time and sustained drug release, desirable for cancer treatment. To achieve this, we have developed paclitaxel-loaded PLGA nanoparticles by emulsification solvent evaporation method and evaluated by in vitro and in vivo studies. The results obtained from in vitro study showed that drug loading efficiency was 84.25% with an initial burst release followed by sustained drug release. Cellular uptake and in vitro cytotoxicity of the formulated nanoparticles using HepG2, Huh-7 cancer cells and Chang liver cells were also investigated. The formulated nanoparticles showed more cytotoxic effect at lower concentration and were internalized well by HepG2 cells compared to free-drug and marketed formulation. Prolonged half-life and higher plasma and liver drug concentrations of the formulated nanoparticles were observed as compared to free drug and marketed formulation in rats. Thus, paclitaxel-loaded polymeric nanoparticle has shown its potential for the treatment of liver cancer.


Assuntos
Sistemas de Liberação de Medicamentos , Ácido Láctico/química , Fígado/metabolismo , Nanopartículas/química , Paclitaxel/farmacocinética , Ácido Poliglicólico/química , Animais , Varredura Diferencial de Calorimetria , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Células Hep G2 , Humanos , Hidrólise , Cinética , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Nanopartículas/ultraestrutura , Paclitaxel/administração & dosagem , Paclitaxel/sangue , Paclitaxel/farmacologia , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos Sprague-Dawley , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Distribuição Tecidual/efeitos dos fármacos
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