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1.
Int J Pharm ; 642: 123136, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37311498

RESUMO

Exemestane (EXE), an irreversible aromatase inhibitor, is primarily used as a first-line therapy for estrogen receptor-positive breast cancer patients. However, complex physicochemical characteristics of EXE limit its oral bioavailability (<10%) and anti-breast cancer efficacy. The present study aimed to develop a novel nanocarrier system to improve the oral bioavailability and anti-breast cancer efficacy of EXE. In this perspective, EXE-loaded TPGS-based polymer lipid hybrid nanoparticles (EXE-TPGS-PLHNPs) were prepared by the nanoprecipitation method and evaluated for their potential in improving oral bioavailability, safety, and therapeutic efficacy in the animal model. EXE-TPGS-PLHNPs showed significantly higher intestinal permeation in comparison to EXE-PLHNPs (without TPGS) and free EXE. After oral administration, EXE-TPGS-PLHNPs and EXE-PLHNPs revealed 3.58 and 4.69 times higher oral bioavailability in Wistar rats compared to the conventional EXE suspension. The results of the acute toxicity experiment suggested that the developed nanocarrier was safe for oral administration. Furthermore, EXE-TPGS-PLHNPs and EXE-PLHNPs represented much better anti-breast cancer activity in Balb/c mice bearing MCF-7 tumor xenograft with tumor inhibition rate of 72.72% and 61.94% respectively in comparison with the conventional EXE suspension (30.79%) after 21 days of oral chemotherapy. In addition, insignificant changes in the histopathological examination of vital organs and hematological analysis further confirm the safety of the developed PLHNPs. Therefore, the findings of the present investigation advocated that the encapsulation of EXE in PLHNPs can be a promising approach for oral chemotherapy of breast cancer.


Assuntos
Neoplasias da Mama , Nanopartículas , Humanos , Ratos , Animais , Camundongos , Feminino , Polímeros/uso terapêutico , Disponibilidade Biológica , Ratos Wistar , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Androstadienos/farmacologia , Androstadienos/uso terapêutico , Lipídeos
2.
J Biomol Struct Dyn ; 41(2): 538-549, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34856883

RESUMO

H2 receptor antagonists are the medication given for treating stomach ulcers, but lately, reports have shown their role in healing several malignant ulcers. The present work entails the interaction of H2 blocker nizatidine with calf thymus (ct)-DNA for determining the binding mode and energetics of the interaction. Multi-spectroscopic, calorimetric, viscometric and bioinformatic analysis revealed that nizatidine interacted with ct-DNA via groove-binding mode and is characterised by exothermic reaction. Moreover, assessment of genotoxic potential of nizatidine in vitro was carried out in peripheral human lymphocytes by alkaline comet assay. DNA damage occurred at high concentrations of nizatidine. Genotoxicity of nizatidine was also evaluated in vivo by assessing cytogenetic biomarkers viz. micronuclei formation and chromosomal aberration test. Nizatidine was able to induce micronuclei formation and chromosomal damage at high dose. Additionally, cytotoxic activity of nizatidine was determined in cancer cell lines, namely HeLa and HCT-116 and compared with the normal human cell line HEK-293 employing MTT assay. It was observed that nizatidine was more toxic towards HeLa and HCT-116 than HEK-293. Cell morphology analysis by compound inverted microscopy further strengthens the finding obtained through MTT assay.


Assuntos
Dano ao DNA , Nizatidina , Humanos , Células HEK293 , Ensaio Cometa , DNA
3.
Mol Cancer Ther ; 22(2): 264-273, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36399634

RESUMO

The canonical model of "small cell lung cancer" (SCLC) depicts tumors arising from dual inactivation of TP53 and RB1. However, many genomic studies have persistently identified tumors with no RB1 mutations. Here, we examined RB1 protein expression and function in SCLC. RB1 expression was examined by IHC analysis of 62 human SCLC tumors. These studies showed that ∼14% of SCLC tumors expressed abundant RB1 protein, which is associated with neuroendocrine gene expression and is enriched in YAP1 expression, but no other lineage proteins that stratify SCLC. SCLC cells and xenograft tumors with RB1 protein expression were sensitive to growth inhibition by the CDK4/6 inhibitor palbociclib, and this inhibition was shown to be dependent on RB1 expression by CRISPR knockout. Furthermore, a patient with biopsy-validated wild-type RB1 SCLC who received the CDK4/6 inhibitor abemaciclib demonstrated a dramatic decrease in mutant TP53 ctDNA allelic fraction from 62.1% to 0.4% and decreased tumor mass on CT scans. Importantly, IHC of the diagnostic biopsy specimen showed RB1 positivity. Finally, we identified a transcriptomics-based RB1 loss-of-function signature that discriminates between SCLC cells with or without RB1 protein expression and validated it in the patient who was responsive to abemaciclib, suggesting its potential use to predict CDK4/6 inhibitor response in patients with SCLC. Our study demonstrates that RB1 protein is an actionable target in a subgroup of SCLC, a cancer that exhibits no currently targetable mutations.


Assuntos
Neoplasias Pulmonares , Neoplasias da Retina , Retinoblastoma , Carcinoma de Pequenas Células do Pulmão , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/metabolismo , Proteína do Retinoblastoma/genética , Mutação , Quinase 4 Dependente de Ciclina/genética
4.
Biochim Biophys Acta Rev Cancer ; 1877(5): 188776, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35961620

RESUMO

Exosomes are 30 to 150 nm-diameter lipid bilayer-enclosed extracellular vesicles that enable cell-to-cell communication through secretion and uptake. The exosomal cargoes contain RNA, lipids, proteins, and metabolites which can be delivered to recipient cells in vivo. In a healthy lung, exosomes facilitate interaction between adaptive and innate immunity and help maintain normal lung physiology. However, tumor-derived exosomes in lung cancer (LC) can, on the other hand, restrict immune cell proliferation, cause apoptosis in activated CD8+ T effector cells, reduce natural killer cell activity, obstruct monocyte differentiation, and promote proliferation of myeloid-derived suppressor and regulatory T cells. In addition, exosomes in the tumor microenvironment may also play a critical role in cancer progression and the development of drug resistance. In this review, we aim to comprehensively examine the current updates on the role of exosomes in lung carcinogenesis and their potential application as a diagnostic, prognostic, and therapeutic tool in lung cancer.


Assuntos
Exossomos , Neoplasias Pulmonares , Exossomos/metabolismo , Humanos , Imunomodulação , Bicamadas Lipídicas/metabolismo , Neoplasias Pulmonares/patologia , RNA , Microambiente Tumoral
5.
Pharmaceuticals (Basel) ; 15(3)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35337078

RESUMO

Some (E)-3-(3-(4-(benzyloxy)phenyl)-1-phenyl-1H-pyrazol-4-yl)-1-phenylprop-2-en-1-one conjugates 5a-r were designed; synthesized; characterized by 1H, 13C NMR, and ESI-MS; and evaluated for tubulin polymerization inhibitory activity and in vitro cytotoxicity against breast (MCF-7), cervical (SiHa), and prostate (PC-3) cancer cell lines, as well as a normal cell line (HEK-293T). The compounds were also tested to determine their binding modes at the colchicine-binding site of tubulin protein (PDB ID-3E22), for in silico ADME prediction, for bioactivity study, and for PASS prediction studies. Among all the synthesized conjugates, compound 5o exhibited excellent cytotoxicity with an IC50 value of 2.13 ± 0.80 µM (MCF-7), 4.34 ± 0.98 µM (SiHa), and 4.46 ± 0.53 µM (PC-3) against cancer cell lines. The compound did not exhibit significant toxicity to the HEK cells. Results of the in silico prediction revealed that the majority of the conjugates possessed drug-like properties.

6.
Nanotechnology ; 32(41)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34198267

RESUMO

Polymer-lipid hybrid nanoparticles (PLHNPs) are novel nanoplatforms for the effective delivery of a lipophilic drug in the management of a variety of solid tumors. The present work was designed to develop exemestane (EXE) encapsulated D-alpha-tocopheryl polyethylene glycol succinate (TPGS) based PLHNPs (EXE-TPGS-PLHNPs) for controlled delivery of EXE for breast cancer management. EXE-TPGS-PLHNPs were formulated by single-step nano-precipitation technique and statistically optimized by a 33Box-Behnken design using Design expert®software. The polycaprolactone (PCL;X1), phospholipon 90 G (PL-90G;X2), and surfactant (X3) were selected as independent factors while particles size (PS;Y1), polydispersity index (PDI;Y2), and %entrapment efficiency (%EE;Y3) were chosen as dependent factors. The average PS, PDI, and %EE of the optimized EXE-TPGS-PLHNPs was observed to be 136.37 ± 3.27 nm, 0.110 ± 0.013, and 88.56 ± 2.15% respectively. The physical state of entrapped EXE was further validated by Fourier-transform infrared spectroscopy, differential scanning calorimetry, and powder x-ray diffraction that revealed complete encapsulation of EXE in the hybrid matrix of PLHNPs with no sign of significant interaction between drug and excipients.In vitrorelease study in simulated gastrointestinal fluids revealed initial fast release for 2 h after that controlled release profile up to 24 h of study. Moreover, optimized EXE-TPGS-PLHNPs exhibited excellent stability in gastrointestinal fluids as well as colloidal stability in different storage concentrations. Furthermore, EXE-TPGS-PLHNPs exhibited distinctively higher cellular uptake and time and dose-dependent cytotoxicity against MCF-7 breast tumor cells compared to EXE-PLHNPs without TPGS and free EXE. The obtained results suggested that EXE-TPGS-PLHNPs can be a promising platform for the controlled delivery of EXE for the effective treatment of breast cancer.


Assuntos
Androstadienos/farmacologia , Antineoplásicos/farmacologia , Portadores de Fármacos/síntese química , Composição de Medicamentos/métodos , Lipossomos/química , Nanopartículas/química , Androstadienos/metabolismo , Antineoplásicos/metabolismo , Materiais Biomiméticos/química , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Análise Fatorial , Corantes Fluorescentes/química , Suco Gástrico/química , Humanos , Cinética , Lipossomos/ultraestrutura , Células MCF-7 , Nanopartículas/ultraestrutura , Fosfatidilcolinas/química , Poliésteres/química , Rodaminas/química , Vitamina E/química
7.
Biochim Biophys Acta Rev Cancer ; 1876(1): 188533, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33785381

RESUMO

Parkin, an E3 ubiquitin ligase has been found to be deregulated in a variety of human cancers. Our current understanding is endowed with strong evidences that Parkin plays crucial role in the pathogenesis of cancer by controlling/interfering with major hallmarks of cancer delineated till today. Consistent with the idea of mitophagy, the existing studies imitates the tumor suppressive potential of Parkin, resolved by its capacity to regulate cell proliferation, cell migration, angiogenesis, apoptosis and overall cellular survival. Dysfunction of Parkin has resulted in the loss of ubiquitination of cell cycle components followed by their accumulation leading to genomic instability, perturbed cell cycle and eventually tumor progression. In this review, we provide an overview of current knowledge about the critical role of Parkin in cancer development and progression and have focussed on its therapeutic implications highlighting the diagnostic and prognostic value of Parkin as a biomarker. We earnestly hope that an in-depth knowledge of Parkin will provide a linchpin to target in various cancers that will open a new door of clinical applications and therapeutics.


Assuntos
Neoplasias/enzimologia , Ubiquitina-Proteína Ligases/metabolismo , Animais , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Ativação Enzimática , Ativadores de Enzimas/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Humanos , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , Transdução de Sinais , Ubiquitina-Proteína Ligases/genética
8.
Anticancer Agents Med Chem ; 21(1): 42-60, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32718297

RESUMO

BACKGROUND: The Epidermal Growth Factor Receptor (known as EGFR) induces cell differentiation and proliferation upon activation through the binding of its ligands. Since EGFR is thought to be involved in the development of cancer, the identification of new target inhibitors is the most viable approach, which recently gained momentum as a potential anticancer therapy. OBJECTIVE: To assess various pyrazole linked pyrazoline derivatives with carbothioamide for EGFR kinase inhibitory as well as anti-proliferative activity against human cancer cell lines viz. A549 (non-small cell lung tumor), MCF-7 (breast cancer cell line), SiHa (cancerous tissues of the cervix uteri), and HCT-116 (colon cancer cell line). METHODS: In vitro EGFR kinase assay, in vitro MTT assay, Lactate dehydrogenase release, nuclear staining (DAPI), and flow cytometry cell analysis. RESULTS: Compounds 6h and 6j inhibited EGFR kinase at concentrations of 1.66µM and 1.9µM, respectively. Furthermore, compounds 6h and 6j showed the most potent anti-proliferative results against the A549 KRAS mutation cell line (IC50 = 9.3 & 10.2µM). Through DAPI staining and phase contrast microscopy, it was established that compounds 6h and 6j also induced apoptotic activity in A549 cells. This activity was further confirmed by FACS using Annexin-V-FITC and Propidium Iodide (PI) labeling. Molecular docking studies performed on 6h and 6j suggested that the compounds can bind to the hinge region of ATP binding site of EGFR tyrosine kinase in a similar pose as that of the standard drug gefitinib. CONCLUSION: The potential anticancer activity of compounds 6h and 6j was confirmed and need further exploration in cancer cell lines of different tissue origin and signaling pathways, as well as in animal models of cancer development.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/síntese química , Tioamidas/química , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/antagonistas & inibidores , Gefitinibe/farmacologia , Gefitinibe/normas , Humanos , Conformação Molecular , Simulação de Acoplamento Molecular , Terapia de Alvo Molecular , Ligação Proteica , Pirazóis/farmacologia , Relação Estrutura-Atividade
9.
Turk J Gastroenterol ; 31(3): 211-220, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32343233

RESUMO

BACKGROUND/AIMS: Alterations in Parkin (PRKN) have been described in many cancers; however, the molecular mechanism that contributes to loss of Parkin expression in colorectal cancer (CRC) remains unclear. The aim of this study was to investigate the involvement of PRKN mutation and loss of heterozygosity (LOH) in loss of Parkin expression. To understand the role of PRKN in cancer progression, we also evaluated the association of Parkin expression with clinicopathological parameters in North Indian population. MATERIALS AND METHODS: We studied 219 CRC samples and their adjacent normal tissues (control) obtained from North Indian patients with CRC. The expression of Parkin was analyzed by immunohistochemistry (IHC). PRKN mutations were analyzed by single-stranded conformational polymorphism (SSCP) and sequencing. For loss of heterozygosity (LOH), we employed two intragenic, D6S305 and D6S1599, and one telomeric marker, D6S1008. RESULTS: In our study, we found four novel somatic mutations, namely, C166G, K413N, R420P (exon 4), and V425E (exon 11). Both mutation in Parkin (p = 0.0014) and LOH (p = 0.0140) were significantly associated with loss of Parkin expression. Additionally, Parkin mutations were not associated with the clinicopathological parameters of the patients. Furthermore, both, LOH in Parkin and Parkin expression were significantly correlated with different clinicopathological variables (p<0.05). CONCLUSION: Our results indicate that Parkin expression is not regulated by a single mechanism, but both mutation and LOH contribute to loss of Parkin expression. We also provide evidence of involvement of Parkin in metastasis and cancer progression. We, therefore, suggest Parkin as a potential prognostic marker and warrant further analysis in this direction.


Assuntos
Neoplasias Colorretais/etnologia , Neoplasias Colorretais/genética , Perda de Heterozigosidade/genética , Ubiquitina-Proteína Ligases/genética , População Branca/genética , Adulto , Progressão da Doença , Feminino , Humanos , Índia/etnologia , Masculino , Pessoa de Meia-Idade , Mutação/genética
10.
Arch Pharm (Weinheim) ; 353(4): e1900262, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32003485

RESUMO

Pyrazoline-linked carboxamide derivatives were designed, synthesized, and evaluated for potential epidermal growth factor receptor (EGFR) kinase inhibition, anticancer activity, and apoptotic and cardiomyopathy toxicity. Compounds 6m and 6n inhibit EGFR kinase at a concentration of 6.5 ± 2.91 and 3.65 ± 0.54 µM, respectively. Some of these compounds showed effects on proliferation, which were also then evaluated against four different human cancer cell lines, that is, MCF-7 (breast cancer), A549 (non-small-cell lung tumor), HCT-116 (colon cancer), and SiHa cells (cancerous tissues of the cervix uteri). The results showed that certain synthetic compounds showed significant inhibitor activity; compounds 6m and 6n were more cytotoxic than doxorubicin against A549 cancer cells, with IC50 values of 10.3 ± 1.07 and 4.6 ± 0.57 µM, respectively. Additionally, compounds 6m and 6n induced apoptosis in A549 cancer cells, as evidenced by 4',6-diamidino-2-phenylindole (DAPI) staining and phase-contrast microscopy. Potency to induce apoptosis by compound 6n was further confirmed by fluorescence-activated cell sorting using Annexin V-FITC and propidium iodide labeling. Compound 6n showed normal cardiomyocytes with no marked sign of pyknotic nuclei in cardiomyopathy and also normal histological appearance of the renal cortex when compared with that of control. Results of molecular docking studies suggested that compounds 6m and 6n can bind to the hinge region of the adenosine triphosphate-binding site of EGFR kinase, like the standard drug erlotinib. Therefore, the present study suggests that compounds 6m and 6n have potent in vitro antitumor activities against the human non-small-cell lung tumor cell line A549, which can be further explored in other cancer cell lines and in animal studies.


Assuntos
Antineoplásicos/farmacologia , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Feminino , Células HEK293 , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Pirazóis/síntese química , Pirazóis/química , Ratos , Ratos Wistar , Relação Estrutura-Atividade
11.
Med Mycol ; 58(1): 93-106, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30843057

RESUMO

The pathogenicity of Candida albicans, an opportunistic human fungal pathogen, is attributed to several virulence factors. ß-citronellol is a monoterpenoid present in several plant essential oils. The present study explores the antifungal potential and mode of action of ß-citronellol against C. albicans ATCC 90028 (standard), C. albicans D-27 (FLC-sensitive), and C. albicans S-1 (FLC-resistant). Anti-Candida potential was studied by performing MIC, MFC, growth curves, disc diffusion, spot assay, and WST1 cytotoxic assay. Morphological transition was monitored microscopically in both solid and liquid hyphae inducing media. ß-citronellol inhibits yeast to hyphal transition in both liquid and solid hyphae inducing media. It had a significant inhibitory effect on biofilm formation and secretion of extracellular proteinases and phospholipases. We showed that it has an adverse effect on membrane ergosterol levels and modulates expression of related ERG genes. Expression profiles of selected genes associated with C. albicans pathogenicity displayed reduced expression in treated cells. This work suggests that ß-citronellol inhibits morphological transition in C. albicans and decreases the secretion of hydrolytic enzymes involved in the early stage of infection as well as modulates the expression of associated genes. Pleiotropic phenotype shown by ß-citronellol treated Candida cells suggests various modes of action. Further studies will assess the clinical application of ß-citronellol in the treatment of fungal infections.


Assuntos
Monoterpenos Acíclicos/farmacologia , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Óleos Voláteis/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Candida albicans/genética , Candida albicans/patogenicidade , Proteínas Fúngicas/genética , Hifas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Fenótipo , Virulência , Fatores de Virulência/genética
12.
BMC Cancer ; 19(1): 820, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31429726

RESUMO

BACKGROUND: Progression of breast cancer involves both genetic and epigenetic factors. Parkin gene has been identified as a tumor suppressor gene in the pathogenesis of various cancers. Nevertheless, the putative role of Parkin in breast cancer remains largely unknown. Therefore, we evaluated the regulation of Parkin through both genetic and epigenetic mechanisms in breast carcinoma. METHOD: A total of 156 breast carcinoma and their normal adjacent tissue samples were included for mutational analysis through SSCP, and sequencing. MS-PCR was employed for methylation study whereas Parkin protein expression was evaluated using immunohistochemistry and western blotting. For the survival analysis, Kaplan-Meier curve and Cox's proportional hazard model were used. RESULTS: In expression analysis, Parkin protein expression was found to be absent in 68% cases of breast cancer. We found that aberrant promoter methylation of Parkin gene is a frequent incident in breast cancer tumors and cell lines. Our MS-PCR result showed that Parkin promoter methylation has a significant role (p = 0.0001) in reducing the expression of Parkin protein. Consistently, expression of Parkin was rectified by treatment with 5-aza-2-deoxycytidine. We also found significant associations of both Parkin negative expression and Parkin promoter methylation with the clinical variables. Furthermore, we found a very low frequency (5.7%) of Parkin mutation with no clinical significance. In survival analysis, patients having Parkin methylation and Parkin loss had a worse outcome compared to those harboring none of these events. CONCLUSION: Overall, these results suggested that promoter methylation-mediated loss of Parkin expression could be used as a prognostic marker for the survival of breast cancer.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Epigênese Genética/genética , Taxa de Mutação , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Biomarcadores Tumorais/genética , Neoplasias da Mama/patologia , Metilação de DNA , Análise Mutacional de DNA , Regulação para Baixo/genética , Éxons/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Estimativa de Kaplan-Meier , Células MCF-7 , Pessoa de Meia-Idade , Prognóstico , Regiões Promotoras Genéticas , Modelos de Riscos Proporcionais , Taxa de Sobrevida
13.
Asian Pac J Cancer Prev ; 20(1): 269-276, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30678449

RESUMO

Background: Breast cancer is a heterogeneous disease that can be subdivided on the basis of histopathological features, genetic alterations, and gene-expression profiles. PTEN gene is considered an established tumor suppressor gene in different types of cancer including breast cancer. However, the role of PTEN alterations in north Indian breast cancer has not been explored especially in defining a group with distinct histological factors. Methodology: 181 sporadic breast cancer and their adjacent normal tissues were included in the present study. We analyzed methylation and LOH through MS-PCR and microsatellite markers respectively. While, for PTEN protein expression, we used immunohistochemistry. All the molecular findings were correlated with the clinicopathological parameters of the patients to underline clinical relevance. Results: We found that LOH and methylation of the PTEN promoter were significantly associated with loss of PTEN protein expression, while, PTEN mutation was a rare event. Furthermore, out of 46 double hit cases (i.e., having both methylation and LOH), 70% (32/46) cases showed complete loss of PTEN expression (P= 0.0249). Both LOH and PTEN promoter methylation were associated significantly with age and clinical stage, while, methylation and loss of PTEN expression were associated with high grade and Her-2 negativity. In addition, a quadruple (ER/PR/ Her-2 and PTEN) negative group with distinct features was found. Conclusion: The pattern of PTEN expression and its correlation with the clinical parameters indicates that loss of PTEN expression defines a clinical group with distinct features. Hence, PTEN expression provides differential therapeutic strategies for north Indian breast cancer.


Assuntos
Neoplasias da Mama/genética , Epigênese Genética/genética , Mutação/genética , PTEN Fosfo-Hidrolase/genética , Biomarcadores Tumorais/genética , Metilação de DNA/genética , Epigenômica/métodos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica/métodos , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética
14.
Eur J Med Chem ; 163: 67-82, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30503944

RESUMO

A series of diketo esters and their pertinent bioisosteres were designed and synthesized as potent antibacterial agents by targeting methionine amino peptidases (MetAPs). In the biochemical assay against purified MetAPs from Streptococcus pneumoniae (SpMetAP1a), Mycobacterium tuberculosis (MtMetAP1c), Enterococcus faecalis (EfMetAP1a) and human (HsMetAP1b), compounds 3a, 4a and 5a showed more than 85% inhibition of all the tested MetAPs at 100 µM concentration. Compounds 4a and 5a also exhibited antibacterial potential with MIC values 62.5 µg/mL (S. pneumoniae), 31.25 µg/mL (E. faecalis), 62.5 µg/mL (Escherichia coli) and 62.5 µg/mL (S. pneumoniae), 62.5 µg/mL (E. coli), respectively. Moreover, 5a also significantly inhibited the growth of multidrug resistant E. coli strains at 512 µg/mL conc., while showing no cytotoxic effect towards healthy CHO cells and thus being selected. Growth kinetics study showed significant inhibition of bacterial growth when treated with different conc. of 5a. TEM analysis also displayed vital damage to bacterial cells by 5a at MIC conc. Moreover, significant inhibition of biofilm formation was observed in bacterial cells treated with MIC conc. of 5a as visualized by SEM micrographs. Interestingly, 5a did not cause an alteration in the hemocyte density in Galleria mellonella larvae which is considered in vivo model for antimicrobial studies and was non-toxic up to a conc. of 2.5 mg/mL.


Assuntos
Antibacterianos/síntese química , Cetoácidos/farmacologia , Animais , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Células CHO , Cricetulus , Enterococcus faecalis/efeitos dos fármacos , Hemócitos/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos
15.
ACS Omega ; 3(6): 6912-6930, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30023966

RESUMO

Despite the vast availability of antibiotics, bacterial infections remain a leading cause of death worldwide. In an effort to enhance the armamentarium against resistant bacterial strains, 1,2,3-triazole (5a-x) and sulfonate (7a-j) analogues of natural bioactive precursors were designed and synthesized. Preliminary screening against two Gram-positive (Streptococcus pneumoniae and Enterococcus faecalis) and four Gram-negative bacterial strains (Pseudomonas aeruginosa, Salmonella enterica, Klebsiella pneumoniae, and Escherichia coli) was performed to assess the potency of these analogues as antibacterial agents. Among all triazole analogues, 5e (derived from carvacrol) and 5u (derived from 2-hydroxy 1,4-naphthoquinone) bearing carboxylic acid functionality emerged as potent antibacterial agents against S. pneumoniae (IC50: 62.53 and 39.33 µg/mL), E. faecalis (IC50: 36.66 and 61.09 µg/mL), and E. coli (IC50: 15.28 and 22.57 µg/mL). Furthermore, 5e and 5u also demonstrated moderate efficacy against multidrug-resistant E. coli strains and were therefore selected for further biological studies. Compound 5e in combination with ciprofloxacin displayed a synergistic effect on multidrug-resistant E. coli MRA11 and MRC17 strains, whereas compound 5u was selective against E. coli MRA11 strain. Growth kinetic studies on S. pneumoniae and E. coli treated with 5e and 5u showed an extended lag phase. 5e and 5u did not show significant cytotoxicity up to 100 µg/mL concentration on human embryonic kidney (HEK293) cells. Transmission electron microscopic (TEM) analysis of bacterial cells (S. pneumoniae and E. coli) exposed to 5e and 5u clearly showed morphological changes and damaged cell walls. Moreover, these compounds also significantly inhibited biofilm formation in S. pneumoniae and E. coli strains, which was visualized by scanning electron microscopic (SEM) analysis. Treatment of larvae of Galleria mellonella (an in vivo model for antimicrobial studies) with 5e and 5u did not cause an alteration in the hemocyte density, thereby indicating lack of an immune response, and were nontoxic up to a concentration of 2.5 mg/mL.

16.
Mol Neurobiol ; 55(8): 6788-6800, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29349575

RESUMO

Parkin for more than a decade has been portrayed as a neuroprotector gene is now increasingly emerging as a multifaceted gene that can exert entirely opposite effects i.e., both cell proliferation and apoptosis. Parkinson's disease, a neurological disease, progresses due to excess in cell death, while, in case of cancer, cell death normally fails to occur. Parkin, an E3 ubiquitin ligase, was first identified as a gene implicated in autosomal recessive juvenile Parkinsonism, but several evidences indicate that Parkin is a tumor suppressor gene, involved in a variety of cancers. It is hard to imagine that two entirely different classes of disease, like cancer and Parkinson's disease, can converge at a critical point attributable to a single gene, Parkin. This mysterious and hidden connection may prove a boon in disguise and has raised hopes that studying the biology of one disease may help to identify novel targets of therapy for the other. In this Parkinson's disease-cancer story, if the detail of Parkin pathway is unraveled and gaps in the storyline are properly filled up, we may end getting an entirely new therapeutic option. This review mainly highlights the recent literature which suggests how Parkin gene regulates the various hallmarks of both the Parkinson's disease and cancer.


Assuntos
Neoplasias/metabolismo , Doença de Parkinson/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Humanos , Mutação/genética , Neuroproteção , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/genética
17.
Tumour Biol ; 37(7): 9089-98, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26762413

RESUMO

Cervical cancer is a major cause of morbidity and mortality particularly in developing countries. Somatic mutations in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) gene is associated with increased sensitivity to tyrosine kinase inhibitors (TKIs). In this study, the presence of EGFR mutations in cervical cancer and its correlation with HPV were identified. EGFR mutations were found in 31 out of 95 patients (32.63 %). Results showed the presence of EGFR mutations in 5.263 % of patients in exon 19. In exon 20, mutations were predominant in 25.26 % patients. While in exon 21, 8.421 % of patients had mutations. HPV, which is associated with cervical cancer development, was found in 95.78 % (HPVL1), 92.63 % (HPV16), and 3.15 % (HPV18) of patients. No correlation was found between HPV16 and EGFR mutations (p = 0.0616). Overall, mutations like V742R, Q787Q, Q849H, E866E, T854A, L858R, E872Q, and E688Q were found. Next, impact of TKI inhibitor (gefitinib) was checked with respect to presence or absence of mutation considering Q787Q mutation in exon 20 (G/A genotype) which is present in 25.2 % patients. Mutated cervical cancer cell lines showed higher sensitivity to gefitinib. Overall, this study suggests the importance of mutations in EGFR gene and indicates their relevance with respect to TKIs treatment in Indian cervical cancer patients.


Assuntos
Receptores ErbB/genética , Papillomavirus Humano 16/patogenicidade , Papillomavirus Humano 18/patogenicidade , Mutação/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia , Adulto , Idoso , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Análise Mutacional de DNA/métodos , Éxons/genética , Feminino , Gefitinibe , Células HeLa , Humanos , Índia , Pessoa de Meia-Idade , Mutação/efeitos dos fármacos , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/virologia , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia , Neoplasias do Colo do Útero/tratamento farmacológico
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