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1.
J Natl Compr Canc Netw ; 22(7): 447-453, 2024 09.
Artículo en Inglés | MEDLINE | ID: mdl-39236758

RESUMEN

BACKGROUND: Adolescent and young adult (AYA) patients with cancer have historically been understudied. Few studies have examined survival disparities associated with racial/ethnic and socioeconomic status (SES) and do not account for the influence of insurance status and access to care. We evaluated the association of SES and race/ethnicity with overall mortality for AYA patients who were members of an integrated health system with relatively equal access to care. METHODS: AYA patients diagnosed with the 15 most common cancer types during 2010 through 2018 at Kaiser Permanente Southern California were included. Neighborhood Deprivation Index (NDI) quartile (Q1: least deprived; Q4: most deprived) was used as a measure of SES. Mortality rate per 1,000 person-years was calculated for each racial/ethnic and NDI subgroup. Multivariable Cox model was used to estimate hazard ratios (HRs) for all-cause mortality adjusting for sex, age and stage at diagnosis, cancer type, race/ethnicity, and NDI. RESULTS: Data for 6,379 patients were tracked for a maximum of 10 years. Crude mortality rates were higher among non-White racial/ethnic patients compared with non-Hispanic (NH)-White patients. In the Cox model, Hispanic (HR, 1.31; P=.004) and NH-Black (HR, 1.34; P=.05) patients experienced significantly higher all-cause mortality risk compared with NH-White patients. Patients from more deprived neighborhoods had higher mortality risk. In the Cox model, there was no significant difference in all-cause mortality between Q1 and Q2 through Q4 (Q2: HR, 0.88; P=.26, Q3: HR, 0.94; P=.56, and Q4: HR, 0.95; P=.70). CONCLUSIONS: For AYAs with cancer with similar access to care, Hispanic and NH-Black patients have higher risk of all-cause mortality than NH-White patients, whereas no significant SES-associated survival disparities were observed. These findings warrant further investigation, awareness, and intervention to address inequities in cancer care among vulnerable populations.


Asunto(s)
Disparidades en Atención de Salud , Neoplasias , Adolescente , Adulto , Femenino , Humanos , Masculino , Adulto Joven , California/epidemiología , Etnicidad , Disparidades en Atención de Salud/estadística & datos numéricos , Neoplasias/mortalidad , Neoplasias/terapia , Clase Social , Factores Socioeconómicos , Grupos Raciales , Mortalidad
2.
JCO Oncol Pract ; 20(2): 254-261, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38060993

RESUMEN

PURPOSE: The Inflation Reduction Act (IRA) includes provisions for price negotiations of certain high-spending drugs in Medicare Parts B and D. This provision received considerable attention from those interested in the costs of cancer care since Medicare covers most patients with cancer and many cancer drugs are expensive. We simulate how many cancer drugs may be eligible for IRA price negotiations and examine the reasons that many are likely to be excluded from negotiation. METHODS: This study uses 2021 Medicare Fee-for-Service Part B and Part D prescription drugs expenditure data. Cancer drugs were identified using the SEER Program list of cancer medications. Our measures included total spending, beneficiary users, and spending-per-beneficiary for all cancer drugs covered under Medicare. Each drug was evaluated for eligibility on the basis of IRA negotiation provisions, including estimated loss of patent exclusivity, current competitors, and orphan drug designation. RESULTS: We found that very few cancer drugs will meet the IRA eligibility thresholds to be included in negotiations. We estimate that only 2.2% of beneficiaries with cancer will see lower costs because of the IRA negotiations. The main reason for this is that although novel cancer drug treatments are priced high, they generally treat relatively few beneficiaries and thus do not meet negotiation eligibility criteria, which are primarily based on a ranking of total spending. CONCLUSION: The IRA negotiation provisions will have limited impact on cancer drug prices and will likely leave most patients with cancer exposed to high drug costs.


Asunto(s)
Antineoplásicos , Medicare Part D , Neoplasias , Anciano , Humanos , Estados Unidos , Negociación , Costos y Análisis de Costo , Gastos en Salud , Neoplasias/tratamiento farmacológico
3.
JCO Oncol Pract ; 19(4): e476-e483, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36638330

RESUMEN

PURPOSE: Numerous biologic drugs will soon be facing biosimilar competition. We study the case of trastuzumab, a revolutionary drug approved in 1998 to treat human epidermal growth factor receptor 2-positive breast cancer, to understand how trends in the price and treatment cost of the originator brand and biosimilar forms of trastuzumab evolved following biosimilar entry. METHODS: We use average sales price data from the Centers for Medicare and Medicaid Services, adjusted for inflation to real 2020 dollars using the consumer price index, to describe price changes for the originator biologic and biosimilar versions of trastuzumab between 2019, when the first biosimilar was covered by Medicare, and 2022, when a total of five biosimilar competitors were on the market. We also estimate total treatment costs of biologic and biosimilar forms of trastuzumab from 2005 to 2022 and describe changes in their market share. RESULTS: We find that the first biosimilar entrant's price was 15% lower than the originator brand in 2019, and the fifth biosimilar entrant's price in 2022 was 58% lower than the originator brand in 2019. Contrary to expectations from prior research, the originator biologic price in 2022 decreased 29% from its 2019 average sales price. Average treatment cost for the biologic and biosimilar versions of trastuzumab combined was $45,659 US dollars lower in 2022 compared with the year before biosimilar entry, 2018. Finally, biosimilar market share grew from only 7% in the first year of entry to 32% in the second year, when three biosimilars were on the market. CONCLUSION: Biosimilar entry may be an effective means of decreasing the cost of biologic cancer treatments. Our findings suggest that policies that support biosimilar entry and encourage use may expand access to necessary treatment and reduce health care costs.


Asunto(s)
Biosimilares Farmacéuticos , Neoplasias de la Mama , Anciano , Humanos , Estados Unidos , Femenino , Trastuzumab/farmacología , Trastuzumab/uso terapéutico , Biosimilares Farmacéuticos/farmacología , Biosimilares Farmacéuticos/uso terapéutico , Medicare , Neoplasias de la Mama/tratamiento farmacológico
4.
ACS Med Chem Lett ; 13(3): 377-387, 2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-35300079

RESUMEN

Aberrant gene-silencing through dysregulation of polycomb protein activity has emerged as an important oncogenic mechanism in cancer, implicating polycomb proteins as important therapeutic targets. Recently, an inhibitor targeting EZH2, the methyltransferase component of PRC2, received U.S. Food and Drug Administration approval following promising clinical responses in cancer patients. However, the current array of EZH2 inhibitors have poor brain penetrance, limiting their use in patients with central nervous system malignancies, a number of which have been shown to be sensitive to EZH2 inhibition. To address this need, we have identified a chemical strategy, based on computational modeling of pyridone-containing EZH2 inhibitor scaffolds, to minimize P-glycoprotein activity, and here we report the first brain-penetrant EZH2 inhibitor, TDI-6118 (compound 5). Additionally, in the course of our attempts to optimize this compound, we discovered TDI-11904 (compound 21), a novel, highly potent, and peripherally active EZH2 inhibitor based on a 7 member ring structure.

5.
Cancer Res ; 81(8): 2002-2014, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33632898

RESUMEN

Pancreatic adenocarcinoma (PDAC) epitomizes a deadly cancer driven by abnormal KRAS signaling. Here, we show that the eIF4A RNA helicase is required for translation of key KRAS signaling molecules and that pharmacological inhibition of eIF4A has single-agent activity against murine and human PDAC models at safe dose levels. EIF4A was uniquely required for the translation of mRNAs with long and highly structured 5' untranslated regions, including those with multiple G-quadruplex elements. Computational analyses identified these features in mRNAs encoding KRAS and key downstream molecules. Transcriptome-scale ribosome footprinting accurately identified eIF4A-dependent mRNAs in PDAC, including critical KRAS signaling molecules such as PI3K, RALA, RAC2, MET, MYC, and YAP1. These findings contrast with a recent study that relied on an older method, polysome fractionation, and implicated redox-related genes as eIF4A clients. Together, our findings highlight the power of ribosome footprinting in conjunction with deep RNA sequencing in accurately decoding translational control mechanisms and define the therapeutic mechanism of eIF4A inhibitors in PDAC. SIGNIFICANCE: These findings document the coordinate, eIF4A-dependent translation of RAS-related oncogenic signaling molecules and demonstrate therapeutic efficacy of eIF4A blockade in pancreatic adenocarcinoma.


Asunto(s)
Adenocarcinoma/metabolismo , Factor 4A Eucariótico de Iniciación/metabolismo , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , ARN Mensajero/metabolismo , Ribosomas/metabolismo , Regiones no Traducidas 5' , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adenocarcinoma/tratamiento farmacológico , Animales , Línea Celular Tumoral , Cicloheximida/farmacología , Factor 4A Eucariótico de Iniciación/antagonistas & inhibidores , G-Cuádruplex , Genes ras/genética , Humanos , Ratones , Ratones Desnudos , Mutación , Trasplante de Neoplasias , Oxidación-Reducción , Neoplasias Pancreáticas/tratamiento farmacológico , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Polirribosomas/metabolismo , Biosíntesis de Proteínas , Inhibidores de la Síntesis de la Proteína/farmacología , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas c-met/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , ARN Helicasas , Análisis de Secuencia de ARN , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transcriptoma , Triterpenos/farmacología , Proteínas Señalizadoras YAP , Proteínas de Unión al GTP rac/genética , Proteínas de Unión al GTP rac/metabolismo , Proteínas de Unión al GTP ral/genética , Proteínas de Unión al GTP ral/metabolismo , Proteína RCA2 de Unión a GTP
6.
ACS Pharmacol Transl Sci ; 2(6): 387-401, 2019 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-32259072

RESUMEN

The integrin αVß3 receptor has been implicated in several important diseases, but no antagonists are approved for human therapy. One possible limitation of current small-molecule antagonists is their ability to induce a major conformational change in the receptor that induces it to adopt a high-affinity ligand-binding state. In response, we used structural inferences from a pure peptide antagonist to design the small-molecule pure antagonists TDI-4161 and TDI-3761. Both compounds inhibit αVß3-mediated cell adhesion to αVß3 ligands, but do not induce the conformational change as judged by antibody binding, electron microscopy, X-ray crystallography, and receptor priming studies. Both compounds demonstrated the favorable property of inhibiting bone resorption in vitro, supporting potential value in treating osteoporosis. Neither, however, had the unfavorable property of the αVß3 antagonist cilengitide of paradoxically enhancing aortic sprout angiogenesis at concentrations below its IC50, which correlates with cilengitide's enhancement of tumor growth in vivo.

7.
J Med Chem ; 61(8): 3491-3502, 2018 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-29617572

RESUMEN

BACE1 is responsible for the first step in APP proteolysis, leading to toxic Aß production, and has been indicated to play a key role in the pathogenesis of Alzheimer's disease. The related isoform BACE2 is thought to be involved in processing of the pigment cell-specific melanocyte protein. To avoid potential effects on pigmentation, we investigated the feasibility for developing isoform-selective BACE1 inhibitors. Cocrystal structures of 47 compounds were analyzed and clustered according to their selectivity profiles. Selective BACE1 inhibitors were found to exhibit two distinct conformational features proximal to the flap and the S3 subpocket. Several new molecules were designed and tested to make use of this observation. The combination of a pyrimidinyl C-ring and a methylcyclohexyl element resulted in lead molecule 28, which exhibited ∼50-fold selectivity. Compared to a nonselective BACE1/2 inhibitor, 28 showed significantly less inhibition of PMEL processing in human melanocytes, indicating good functional selectivity of this inhibitor class.


Asunto(s)
Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Ácido Aspártico Endopeptidasas/antagonistas & inhibidores , Inhibidores de Proteasas/farmacología , Secretasas de la Proteína Precursora del Amiloide/química , Péptidos beta-Amiloides/metabolismo , Animales , Ácido Aspártico Endopeptidasas/química , Encéfalo/metabolismo , Dominio Catalítico , Perros , Femenino , Humanos , Células de Riñón Canino Madin Darby , Masculino , Ratones Endogámicos C57BL , Estructura Molecular , Oxazoles/síntesis química , Oxazoles/química , Oxazoles/farmacocinética , Oxazoles/farmacología , Fragmentos de Péptidos/metabolismo , Inhibidores de Proteasas/síntesis química , Inhibidores de Proteasas/química , Inhibidores de Proteasas/farmacocinética , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/química , Ratas , Compuestos de Espiro/síntesis química , Compuestos de Espiro/química , Compuestos de Espiro/farmacocinética , Compuestos de Espiro/farmacología , Relación Estructura-Actividad , Antígeno gp100 del Melanoma/metabolismo
9.
Bioorg Med Chem Lett ; 27(2): 171-175, 2017 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-27939174

RESUMEN

This letter describes the chemical optimization of a novel series of M4 positive allosteric modulators (PAMs) based on a 5-amino-thieno[2,3-c]pyridazine core, developed via iterative parallel synthesis, and culminating in the highly utilized rodent in vivo tool compound, VU0467154 (5). This is the first report of the optimization campaign (SAR and DMPK profiling) that led to the discovery of VU0467154, and details all of the challenges faced in allosteric modulator programs (steep SAR, species differences in PAM pharmacology and subtle structural changes affecting CNS penetration).


Asunto(s)
Piridazinas/farmacología , Receptor Muscarínico M4/agonistas , Tiofenos/farmacología , Animales , Humanos , Ligandos , Proteínas de Transporte de Nucleósidos/metabolismo , Piridazinas/administración & dosificación , Piridazinas/síntesis química , Piridazinas/farmacocinética , Ratas Sprague-Dawley , Relación Estructura-Actividad , Tiofenos/administración & dosificación , Tiofenos/síntesis química , Tiofenos/farmacocinética
10.
PLoS One ; 11(9): e0162384, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27598782

RESUMEN

The apolipoprotein E (APOE) gene is the most highly associated susceptibility locus for late onset Alzheimer's Disease (AD), and augmenting the beneficial physiological functions of apoE is a proposed therapeutic strategy. In a high throughput phenotypic screen for small molecules that enhance apoE secretion from human CCF-STTG1 astrocytoma cells, we show the chrysanthemic ester 82879 robustly increases expressed apoE up to 9.4-fold and secreted apoE up to 6-fold and is associated with increased total cholesterol in conditioned media. Compound 82879 is unique as structural analogues, including pyrethroid esters, show no effect on apoE expression or secretion. 82879 also stimulates liver x receptor (LXR) target genes including ATP binding cassette A1 (ABCA1), LXRα and inducible degrader of low density lipoprotein receptor (IDOL) at both mRNA and protein levels. In particular, the lipid transporter ABCA1 was increased by up to 10.6-fold upon 82879 treatment. The findings from CCF-STTG1 cells were confirmed in primary human astrocytes from three donors, where increased apoE and ABCA1 was observed along with elevated secretion of high-density lipoprotein (HDL)-like apoE particles. Nuclear receptor transactivation assays revealed modest direct LXR agonism by compound 82879, yet 10 µM of 82879 significantly upregulated apoE mRNA in mouse embryonic fibroblasts (MEFs) depleted of both LXRα and LXRß, demonstrating that 82879 can also induce apoE expression independent of LXR transactivation. By contrast, deletion of LXRs in MEFs completely blocked mRNA changes in ABCA1 even at 10 µM of 82879, indicating the ability of 82879 to stimulate ABCA1 expression is entirely dependent on LXR transactivation. Taken together, compound 82879 is a novel chrysanthemic ester capable of modulating apoE secretion as well as apoE-associated lipid metabolic pathways in astrocytes, which is structurally and mechanistically distinct from known LXR agonists.


Asunto(s)
Transportador 1 de Casete de Unión a ATP/genética , Apolipoproteínas E/genética , Astrocitos/efectos de los fármacos , Receptores X del Hígado/genética , Piretrinas/farmacología , Receptores de LDL/genética , Transportador 1 de Casete de Unión a ATP/agonistas , Transportador 1 de Casete de Unión a ATP/metabolismo , Animales , Apolipoproteínas E/agonistas , Apolipoproteínas E/metabolismo , Astrocitos/citología , Astrocitos/metabolismo , Línea Celular Tumoral , Ésteres , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Regulación de la Expresión Génica , Ensayos Analíticos de Alto Rendimiento , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Receptores X del Hígado/agonistas , Receptores X del Hígado/metabolismo , Ratones , Receptores Nucleares Huérfanos/genética , Receptores Nucleares Huérfanos/metabolismo , Cultivo Primario de Células , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de LDL/agonistas , Receptores de LDL/metabolismo , Transducción de Señal
11.
Med Care ; 51(6): 487-93, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23552431

RESUMEN

BACKGROUND: The patient-centered medical home (PCMH) has increasingly been looked to by policy makers, health care providers, and private insurers as a potential solution to the fragmented and inefficient US health care system. Whether the PCMH achieves these goals is not known. OBJECTIVES: To evaluate a PCMH demonstration project implemented in 2011 in 8 New Jersey primary care practices covering over 10,000 plan members. RESEARCH DESIGN: We conduct difference-in-differences analysis, comparing changes in outcomes at 8 medical home practices to a group of 24 comparison practices before (2010) and after (2011) the medical home implementation occurred. We use Mahalanobis distance matching to select the 24 comparison practices, matching on practice characteristics. We focus on the effect of the PCMH pilot on 3 groups of outcomes: health care utilization, costs, and quality. RESULTS: The study cohort included 35,059 members during the study period 2010-2011-10,004 in the 8 PCMH practices and 25,055 in the 24 comparison practices. Health care utilization and costs did not significantly change with adoption of the PCMH model. In testing for changes in Healthcare Effectiveness and Data Information Set (HEDIS) quality measures, rates of mammography increased in PCMH practices after PCMH implementation compared to non-PCMH practices, by 2.2 percentage points on a base of 69.5% (P<0.001). Rates of nephropathy screening also increased (by 6.6 percentage points on a base of 51.8%; P=0.05). Changes in 7 other HEDIS quality measures following PCMH implementation were not statistically significant. CONCLUSIONS: We find little evidence of reductions in health care utilization or cost and minimal evidence of improvements in quality of care. Ongoing work is needed to understand why this model of care seems to work in some cases and not others and to evaluate how to improve the medical home.


Asunto(s)
Atención Dirigida al Paciente , Atención Primaria de Salud , Sistema de Pago Simple , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Organizacionales , New Jersey , Innovación Organizacional , Proyectos Piloto , Calidad de la Atención de Salud
12.
J Biol Chem ; 285(22): 17054-64, 2010 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-20356837

RESUMEN

Selective androgen receptor modulators (SARMs) are androgen receptor (AR) ligands that induce anabolism while having reduced effects in reproductive tissues. In various experimental contexts SARMs fully activate, partially activate, or even antagonize the AR, but how these complex activities translate into tissue selectivity is not known. Here, we probed receptor function using >1000 synthetic AR ligands. These compounds produced a spectrum of activities in each assay ranging from 0 to 100% of maximal response. By testing different classes of compounds in ovariectomized rats, we established that ligands that transactivated a model promoter 40-80% of an agonist, recruited the coactivator GRIP-1 <15%, and stabilized the N-/C-terminal interdomain interaction <7% induced bone formation with reduced effects in the uterus and in sebaceous glands. Using these criteria, multiple SARMs were synthesized including MK-0773, a 4-aza-steroid that exhibited tissue selectivity in humans. Thus, AR activated to moderate levels due to reduced cofactor recruitment, and N-/C-terminal interactions produce a fully anabolic response, whereas more complete receptor activation is required for reproductive effects. This bimodal activation provides a molecular basis for the development of SARMs.


Asunto(s)
Andrógenos/metabolismo , Azaesteroides/farmacología , Antagonistas de Hormonas/farmacología , Receptores Androgénicos/química , Transcripción Genética , Animales , Azaesteroides/química , Células COS , Línea Celular Tumoral , Química Farmacéutica/métodos , Chlorocebus aethiops , Diseño de Fármacos , Femenino , Humanos , Ligandos , Masculino , Modelos Biológicos , Estructura Terciaria de Proteína , Ratas , Receptores Citoplasmáticos y Nucleares/metabolismo , Esteroides/metabolismo , Activación Transcripcional
13.
J Biol Chem ; 284(52): 36367-36376, 2009 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-19846549

RESUMEN

Androgen replacement therapy is a promising strategy for the treatment of frailty; however, androgens pose risks for unwanted effects including virilization and hypertrophy of reproductive organs. Selective Androgen Receptor Modulators (SARMs) retain the anabolic properties of androgens in bone and muscle while having reduced effects in other tissues. We describe two structurally similar 4-aza-steroidal androgen receptor (AR) ligands, Cl-4AS-1, a full agonist, and TFM-4AS-1, which is a SARM. TFM-4AS-1 is a potent AR ligand (IC(50), 38 nm) that partially activates an AR-dependent MMTV promoter (55% of maximal response) while antagonizing the N-terminal/C-terminal interaction within AR that is required for full receptor activation. Microarray analyses of MDA-MB-453 cells show that whereas Cl-4AS-1 behaves like 5alpha-dihydrotestosterone (DHT), TFM-4AS-1 acts as a gene-selective agonist, inducing some genes as effectively as DHT and others to a lesser extent or not at all. This gene-selective agonism manifests as tissue-selectivity: in ovariectomized rats, Cl-4AS-1 mimics DHT while TFM-4AS-1 promotes the accrual of bone and muscle mass while having reduced effects on reproductive organs and sebaceous glands. Moreover, TFM-4AS-1 does not promote prostate growth and antagonizes DHT in seminal vesicles. To confirm that the biochemical properties of TFM-4AS-1 confer tissue selectivity, we identified a structurally unrelated compound, FTBU-1, with partial agonist activity coupled with antagonism of the N-terminal/C-terminal interaction and found that it also behaves as a SARM. TFM-4AS-1 and FTBU-1 represent two new classes of SARMs and will allow for comparative studies aimed at understanding the biophysical and physiological basis of tissue-selective effects of nuclear receptor ligands.


Asunto(s)
Anabolizantes/farmacocinética , Andrógenos , Congéneres de la Testosterona/farmacología , Anabolizantes/química , Animales , Antígenos Virales de Tumores/metabolismo , Masculino , Regiones Promotoras Genéticas , Próstata/crecimiento & desarrollo , Próstata/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores Androgénicos/metabolismo , Congéneres de la Testosterona/química , Proteínas del Núcleo Viral/metabolismo
14.
J Med Chem ; 52(15): 4578-81, 2009 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-19606870

RESUMEN

A novel series of 16-substituted-4-azasteroids has been identified as potential tissue-selective androgen receptor modulators. These ligands display potent hAR binding and agonist activity, low virilizing potential, and good pharmacokinetic profiles in dogs. On the basis of its in vitro profile, 21 was evaluated in the OVX and ORX rat models and exhibited an osteoanabolic, tissue-selective profile.


Asunto(s)
Azaesteroides/síntesis química , Receptores Androgénicos/efectos de los fármacos , Andrógenos , Animales , Azaesteroides/farmacología , Perros , Diseño de Fármacos , Canal de Potasio ERG1 , Canales de Potasio Éter-A-Go-Go/metabolismo , Femenino , Humanos , Masculino , Especificidad de Órganos , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad
17.
Mol Cancer Ther ; 4(2): 271-9, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15713898

RESUMEN

Recent studies indicate that dysregulation of the Akt/PKB family of serine/threonine kinases is a prominent feature of many human cancers. The Akt/PKB family is composed of three members termed Akt1/PKBalpha, Akt2/PKBbeta, and Akt3/PKBgamma. It is currently not known to what extent there is functional overlap between these family members. We have recently identified small molecule inhibitors of Akt. These compounds have pleckstrin homology domain-dependent, isozyme-specific activity. In this report, we present data showing the relative contribution that inhibition of the different isozymes has on the apoptotic response of tumor cells to a variety of chemotherapies. In multiple cell backgrounds, maximal induction of caspase-3 activity is achieved when both Akt1 and Akt2 are inhibited. This induction is not reversed by overexpression of functionally active Akt3. The level of caspase-3 activation achieved under these conditions is equivalent to that observed with the phosphatidylinositol-3-kinase inhibitor LY294002. We also show that in different tumor cell backgrounds inhibition of mammalian target of rapamycin, a downstream substrate of Akt, is less effective in inducing caspase-3 activity than inhibition of Akt1 and Akt2. This shows that the survival phenotype conferred by Akt can be mediated by signaling pathways independent of mammalian target of rapamycin in some tumor cell backgrounds. Finally, we show that inhibition of both Akt1 and Akt2 selectively sensitizes tumor cells, but not normal cells, to apoptotic stimuli.


Asunto(s)
Apoptosis/fisiología , Neoplasias/enzimología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Quinasas Dependientes de 3-Fosfoinosítido , Antibióticos Antineoplásicos/farmacología , Caspasa 3 , Caspasas/metabolismo , Cromonas/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Activación Enzimática , Humanos , Morfolinas/farmacología , Isoformas de Proteínas/química , Isoformas de Proteínas/farmacología , Proteínas Serina-Treonina Quinasas/fisiología , Proteínas Proto-Oncogénicas/fisiología , Proteínas Proto-Oncogénicas c-akt , Sirolimus/farmacología , Células Tumorales Cultivadas
18.
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