RESUMO
Preoperative progesterone intervention has been shown to confer a survival benefit to breast cancer patients independently of their progesterone receptor (PR) status. This observation raises the question how progesterone affects the outcome of PR-negative cancer. Here, using microarray and RNA-Seq-based gene expression profiling and ChIP-Seq analyses of breast cancer cells, we observed that the serum- and glucocorticoid-regulated kinase gene (SGK1) and the tumor metastasis-suppressor gene N-Myc downstream regulated gene 1 (NDRG1) are up-regulated and that the microRNAs miR-29a and miR-101-1 targeting the 3'-UTR of SGK1 are down-regulated in response to progesterone. We further demonstrate a dual-phase transcriptional and post-transcriptional regulation of SGK1 in response to progesterone, leading to an up-regulation of NDRG1 that is mediated by a set of genes regulated by the transcription factor AP-1. We found that NDRG1, in turn, inactivates a set of kinases, impeding the invasion and migration of breast cancer cells. In summary, we propose a model for the mode of action of progesterone in breast cancer. This model helps decipher the molecular basis of observations in a randomized clinical trial of the effect of progesterone on breast cancer and has therefore the potential to improve the prognosis of breast cancer patients receiving preoperative progesterone treatment.
Assuntos
Neoplasias da Mama/patologia , Proteínas de Ciclo Celular/metabolismo , Proteínas Imediatamente Precoces/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Progesterona/farmacologia , Proteínas Serina-Treonina Quinases/genética , Receptores de Progesterona/metabolismo , Fator de Transcrição AP-1/metabolismo , Regulação para Cima/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Receptores ErbB/metabolismo , Humanos , Proteínas Imediatamente Precoces/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Invasividade Neoplásica , Proteínas Serina-Treonina Quinases/metabolismoRESUMO
We describe the formulation of bovine serum albumin nanoparticles (BSA-NPs) by the coacervation method using surfactants. Plasmids (pUC18, pUC18egfp and pBBR1MCS-2) isolated from E. coli were incorporated into the BSA matrix by incubating in albumin solution prior to formulation of NPs. Plasmid incorporation was calculated by % yield, entrapment efficiency, DNA loading capacity and release of entrapped DNA by comparing with blank NPs. BSA-DNA binding studies were carried out by using fluorescence spectroscopy and Fourier Transform Infra Red Spectroscopy (FT-IR). The surface charge distribution of the NPs loaded with plasmid was calculated using zeta potential. The photoluminescence of BSA-NPs was quenched when loaded with pDNA, confirming the interaction of DNA with BSA. Altogether, these results provide evidences for the excellent DNA carrying efficiency of BSA-NPs without loss of plasmid's integrity. The NPs were used to transfect E. coli DH5α strain lacking ampicillin resistance. They, however, showed ampicillin resistance subsequent to transfection with plasmid encoding ampicillin resistance gene. Effect of transfection was confirmed by confocal microscopy and by the isolation of the plasmid by agarose gel electrophoresis from the transfected bacterial culture. This study clearly demonstrates the efficacy of BSA-NPs as delivery vehicle for pDNA transfection.
Assuntos
Escherichia coli/genética , Nanopartículas/química , Soroalbumina Bovina/química , Transfecção/métodos , DNA/administração & dosagem , DNA/metabolismo , Medições Luminescentes , Microscopia Eletrônica de Transmissão , Plasmídeos , Soroalbumina Bovina/metabolismo , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Rhizosphere microorganisms possessing phytase activity are considered important for rendering phytate-P available to plants. In the present study, Citrobacter braakii phytase gene (appA) was over-expressed in rhizobacteria possessing plant growth promoting (PGP) traits for increasing their potential as bioinoculants. AppA was cloned under the lac promoter in the broad host-range expression vector pBBR1MCS2. Transformation of the recombinant construct pCBappA resulted in high constitutive phytase activity in all of the eight rhizobacterial strains belonging to genera Pantoea, Citrobacter, Enterobacter, Pseudomonas (two strains), Rhizobium (two strains) and Ensifer that were studied. Transgenic rhizobacterial strains were found to display varying level of phytase activity, ranging from 10 folds to 538 folds higher than the corresponding control strains. Transgenic derivative of Pseudomonas fluorescens CHA0, a well-characterized plant growth promoting rhizobacterium, showed highest expression of phytase (~8 U/ mg) activity in crude extracts. Although all transformants showed high phytase activity, rhizobacteria having ability to secrete organic acid, showed significantly higher release of P from Ca-phytate in buffered minimal media. AppA over-expressing rhizobacteria showed increased P content, dry weight (shoot) or shoot/ root ratio of mung bean (Vigna radiata) plants, to different extents, when grown in semi solid agar (SSA) medium containing Na-phytate or Ca-phytate as the P sources. This is the first report of over-expression of phytase in rhizobacterial strains and its exploitation for plant growth enhancement.
Assuntos
6-Fitase/genética , Bactérias/genética , Proteínas de Bactérias/genética , Citrobacter/enzimologia , Fabaceae/metabolismo , Fósforo/metabolismo , Ácido Fítico/metabolismo , Rizosfera , 6-Fitase/metabolismo , Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Fabaceae/crescimento & desenvolvimento , Fabaceae/microbiologia , Expressão Gênica , Microbiologia do Solo , Transformação BacterianaRESUMO
Tamoxifen (TAM) is the choice of a drug approved by the Food and Drug Administration (FDA) for the treatment of estrogen-positive receptor (ER+) breast cancer. Sulphoraphane (SFN), a natural plant antioxidant compound, also acts on estrogen-positive breast cancer receptor. Thus, a combination of TAM with SFN is preferred as it helps to minimize the drug-related toxicity and increases the therapeutic efficacy by providing synergistic anticancer effects of both drugs. In the present study, a new simple, sensitive, precise, and selective UPLC-MS/MS method was developed for the simultaneous quantification of tamoxifen and sulphoraphane using propranolol as an internal standard (IS) in rat plasma. Chromatographic separation was achieved on reverse phase Acquity UPLC BEH C18 column (50 mm × 2.1 mm, i.d., 1.7 µm) with an isocratic mobile phase composed of solvent A (0.1% formic acid in acetonitrile) and B (0.1% formic acid in water) (80:20, v/v) at a flow-rate of 0.4 mL/min. The detection and quantification of analytes was performed on Waters ZsprayTM Xevo TQD using selected-ion monitoring operated under a positive electrospray ionization mode. The transitions were m/z = 372.0 [M+H]+ â 71.92 for tamoxifen, m/z = 177.9 [M+H]+ â 113.9 for sulphoraphane and m/z = 260.3 [M+H]+ â 116.1 for propranolol. The method was linear over the concentration range of 8-500 ng/mL (r2 = 0.9996) for tamoxifen, 30-2000 ng/mL (r2 = 0.9998) for sulphoraphane with insignificant matrix effect and high extraction recovery on spiked quality control (QC) samples. The intra- and inter-batch precisions and accuracy were within the acceptable limits, and both the analytes were found to be stable throughout the short term, long term and freeze thaw stability studies. The validated method was successfully applied for the simultaneous estimation of TAM and SFN in an oral pharmacokinetic study in female Wistar rats. This developed UPLC-MS/MS method could be a valuable tool for future pharmacokinetic interaction, therapeutic drug monitoring and pharmacokinetic characterization of novel formulations.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Isotiocianatos/sangue , Sulfóxidos/sangue , Tamoxifeno/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Estabilidade de Medicamentos , Feminino , Isotiocianatos/química , Isotiocianatos/farmacocinética , Modelos Lineares , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sulfóxidos/química , Sulfóxidos/farmacocinética , Tamoxifeno/química , Tamoxifeno/farmacocinéticaRESUMO
Severe acute respiratory syndrome coronavirus (CoV)-2 (SARS-CoV-2), previously called 2019 novel CoV, emerged from China in late December 2019. This virus causes CoV disease-19 (COVID-19), which has been proven a global pandemic leading to a major outbreak. As of June 19, 2020, the data from the World Health Organization (WHO) showed more than 8.7 million confirmed cases in over 200 countries/regions. The WHO has declared COVID-19 as the sixth public health emergency of international concern on January 30, 2020. CoVs cause illnesses that range in severity from the common cold to severe respiratory illnesses and death. Nevertheless, with technological advances and imperative lessons gained from prior outbreaks, humankind is better outfitted to deal with the latest emerging group of CoVs. Studies on the development of in vitro diagnostic tests, vaccines, and drug re-purposing are being carried out in this field. Currently, no approved treatment is available for SARS-CoV-2 given the lack of evidence. The results from preliminary clinical trials have been mixed as far as improvement in the clinical condition and reduction in the duration of treatment are concerned. A number of new clinical trials are currently in progress to test the efficacy and safety of various approved drugs. This review focuses on recent advancements in the field of development of diagnostic tests, vaccines, and treatment approaches for COVID-19.
Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19/diagnóstico , COVID-19/prevenção & controle , Teste para COVID-19 , China/epidemiologia , HumanosRESUMO
OBJECTIVE: Hormonal therapy is an important component of first line of treatment for breast cancer. Response to hormonal therapy is influenced by the progesterone receptor (PR)-status of breast cancer patients. However as an early effect, exposure to progesterone decreases expression of PR in breast cancer cells. An understanding of the mechanism underlying down-regulation of PR could help improve response to hormonal therapy. METHODS: We performed small RNA sequencing of breast cancer cells for identification of microRNAs targeting PR in response to progesterone treatment. Biochemical approaches were used to validate the findings in breast cancer cells. RESULTS: Analysis of small RNA sequencing of four breast cancer cell lines treated with progesterone revealed an up-regulation of miR-129-2 independent of the PR status of the cells. We show that miR-129-2 targets 3'UTR of PR to down-regulate its expression. Furthermore, inhibition of miR-129-2 expression rescues the down-regulation of PR in breast cancer cells. Also, the expression levels of miR-129-2 was observed to be elevated in patients with low expression of PR in the TCGA cohort (n = 359). CONCLUSION: miR-129-2 mediates down-regulation of PR in breast cancer cells in response to progesterone, while anti-miR-129-2 could potentiate PR expression levels among patients with inadequate PR levels. Thus, modulation of activity of miR-129-2 could stabilize PR expression and potentially improve response to hormonal therapy under adjuvant or neo-adjuvant settings.
Assuntos
Neoplasias da Mama/tratamento farmacológico , MicroRNAs/metabolismo , Progesterona/farmacologia , Progestinas/farmacologia , Receptores de Progesterona/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Quimioterapia Adjuvante/métodos , Conjuntos de Dados como Assunto , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/antagonistas & inibidores , Progesterona/uso terapêutico , Progestinas/uso terapêutico , Análise de Sequência de RNARESUMO
Molecular diagnostics has changed the way lung cancer patients are treated worldwide. Of several different testing methods available, PCR followed by directed sequencing and amplification refractory mutation system (ARMS) are the two most commonly used diagnostic methods worldwide to detect mutations at KRAS exon 2 and EGFR kinase domain exons 18-21 in lung cancer. Compared to ARMS, the PCR followed by directed sequencing approach is relatively inexpensive but more cumbersome to perform. Moreover, with a limiting amount of genomic DNA from clinical formalin-fixed, paraffin-embedded (FFPE) specimens or fine biopsies of lung tumors, multiple rounds of PCR and sequencing reactions often get challenging. Here, we report a novel and cost-effective single multiplex-PCR based method, CRE (for Co-amplification of five K RAS and E GFR exons), followed by concatenation of the PCR product as a single linear fragment for direct sequencing. CRE is a robust protocol that can be adapted for routine use in clinical diagnostics with reduced variability, cost and turnaround time requiring a minimal amount of template DNA extracted from FFPE or fresh frozen tumor samples. As a proof of principle, CRE is able to detect the activating EGFR L858R and T790M EGFR mutations in lung cancer cell line and primary tumors.