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1.
J Oral Maxillofac Pathol ; 27(3): 585-591, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38033940

RESUMO

Background: The most important step in identifying an unknown person is determining one's gender and as a dentist, the oral tissues are potential sources of information in this aspect. A study was carried out to assess and evaluate the accuracy of cheiloscopy, pulp tissue, and fingerprints in determining gender. Material and Methods: A study comprising of 160 individuals (80 males and 80 females) was conducted. After obtaining informed written consent and recording their bio-data; lip prints, and fingerprints were recorded. The patients' extracted tooth was collected, their pulp extirpated, for assessment of the Barr body. Results: We found that every lip pattern was unique and hence can be used to identify an unknown individual. The occurrence of the Barr body was determined, and all female samples were found to be positive for the existence of the Barr body. In fingerprint patterns, a significant difference was noted between both sexes with ulnar loops and whorl patterns only. A highly significant difference was observed in the fingerprint ridge density between genders. Conclusions: We conclude that the Barr body in pulpal tissue can be considered as the best possible technique for gender determination within the dental tissues. Lip prints did not show any differences in genders and had no role to play in gender determination. Fingerprint ridge density can also be used to determine gender.

2.
ACS Med Chem Lett ; 14(7): 977-985, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37465292

RESUMO

The AAA+ ATPase p97 (valosin-containing protein, VCP) is a master regulator of protein homeostasis and therefore represents a novel target for cancer therapy. Starting from a known allosteric inhibitor, NMS-873, we systematically optimized this scaffold, in particular, by applying a benzene-to-acetylene isosteric replacement strategy, specific incorporation of F, and eutomer/distomer identification, which led to compounds that exhibited nanomolar biochemical and cell-based potency. In cellular pharmacodynamic assays, robust effects on biomarkers of p97 inhibition and apoptosis, including increased levels of ubiquitinated proteins, CHOP and cleaved caspase 3, were observed. Compound (R)-29 (UPCDC-30766) represents the most potent allosteric inhibitor of p97 reported to date.

3.
Redox Biol ; 61: 102650, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36870109

RESUMO

Growing cancer cells effectively evade most programs of regulated cell death, particularly apoptosis. This necessitates a search for alternative therapeutic modalities to cause cancer cell's demise, among them - ferroptosis. One of the obstacles to using pro-ferroptotic agents to treat cancer is the lack of adequate biomarkers of ferroptosis. Ferroptosis is accompanied by peroxidation of polyunsaturated species of phosphatidylethanolamine (PE) to hydroperoxy- (-OOH) derivatives, which act as death signals. We demonstrate that RSL3-induced death of A375 melanoma cells in vitro was fully preventable by ferrostatin-1, suggesting their high susceptibility to ferroptosis. Treatment of A375 cells with RSL3 caused a significant accumulation of PE-(18:0/20:4-OOH) and PE-(18:0/22:4-OOH), the biomarkers of ferroptosis, as well as oxidatively truncated products - PE-(18:0/hydroxy-8-oxo-oct-6-enoic acid (HOOA) and PC-(18:0/HOOA). A significant suppressive effect of RSL3 on melanoma growth was observed in vivo (utilizing a xenograft model of inoculation of GFP-labeled A375 cells into immune-deficient athymic nude mice). Redox phospholipidomics revealed elevated levels of 18:0/20:4-OOH in RSL3-treated group vs controls. In addition, PE-(18:0/20:4-OOH) species were identified as major contributors to the separation of control and RSL3-treated groups, with the highest variable importance in projection predictive score. Pearson correlation analysis revealed an association between tumor weight and contents of PE-(18:0/20:4-OOH) (r = -0.505), PE-18:0/HOOA (r = -0.547) and PE 16:0-HOOA (r = -0.503). Thus, LC-MS/MS based redox lipidomics is a sensitive and precise approach for the detection and characterization of phospholipid biomarkers of ferroptosis induced in cancer cells by radio- and chemotherapy.


Assuntos
Melanoma , Espectrometria de Massas em Tandem , Animais , Camundongos , Humanos , Peroxidação de Lipídeos , Morte Celular , Camundongos Nus , Cromatografia Líquida , Oxirredução
4.
Mol Cancer Ther ; 21(10): 1510-1523, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-35876604

RESUMO

Pet dogs with naturally occurring cancers play an important role in studies of cancer biology and drug development. We assessed tolerability, efficacy, and pharmacokinetic/pharmacodynamic relationships with a first-in-class small molecule inhibitor of valosin-containing protein (VCP/p97), CB-5339, administered to 24 tumor-bearing pet dogs. Tumor types assessed included solid malignancies, lymphomas, and multiple myeloma. Through a stepwise dose and schedule escalation schema, we determined the maximum tolerated dose to be 7.5 mg/kg when administered orally on a 4 days on, 3 days off schedule per week for 3 consecutive weeks. Adverse events were minimal and mainly related to the gastrointestinal system. Pharmacokinetic/pharmacodynamic data suggest a relationship between exposure and modulation of targets related to induction of the unfolded protein response, but not to tolerability of the agent. An efficacy signal was detected in 33% (2/6) of dogs with multiple myeloma, consistent with a mechanism of action relating to induction of proteotoxic stress in a tumor type with abundant protein production. Clinical trials of CB-5339 in humans with acute myelogenous leukemia and multiple myeloma are ongoing.


Assuntos
Antineoplásicos , Linfoma , Mieloma Múltiplo , Proteína com Valosina , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Cães , Inibidores Enzimáticos/uso terapêutico , Linfoma/tratamento farmacológico , Linfoma/patologia , Linfoma/veterinária , Dose Máxima Tolerável , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Mieloma Múltiplo/veterinária , Resposta a Proteínas não Dobradas , Proteína com Valosina/antagonistas & inibidores
5.
World J Surg Oncol ; 19(1): 349, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930342

RESUMO

BACKGROUND: Previous studies on sternocleidomastoid flaps, have defined the importance of preserving sternocleidomastoid (SCM) branch of superior thyroid artery (STA). This theory drew criticism, as this muscle is known to be a type II muscle, i.e., the muscle has one dominant pedicle (branches from the occipital artery at the superior pole) and smaller vascular pedicles entering the belly of muscle (branches from STA and thyrocervical trunk) at the middle and lower pole respectively. It was unlikely for the SCM branch of STA to supply the upper and lower thirds of the muscle. We undertook a cadaveric angiographic study to investigate distribution of STA supply to SCM muscle. METHODS: It is a cross-sectional descriptive study on 10 cadaveric SCM muscles along with ipsilateral STA which were evaluated with angiography using diatrizoate (urograffin) dye. Radiographic films were interpreted looking at the opacification of the muscle. Results were analyzed using frequency distribution and percentage. RESULTS: Out of ten specimens, near complete opacification was observed in eight SCM muscle specimens. While one showed poor uptake in the lower third of the muscle, the other showed poor uptake in the upper third segment of muscle. CONCLUSION: Based on the above findings we suggest to further investigate sternocleidomastoid muscle as a type III flap, as the STA branch also supplies the whole muscle along with previously described pedicle from occipital artery. However, this needs to be further corroborated intra-operatively using scanning laser doppler. This also explains better survival rates of superior thyroid artery based sternomastoid flaps.


Assuntos
Pescoço , Retalhos Cirúrgicos , Estudos Transversais , Humanos , Artéria Subclávia , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/cirurgia
6.
J Pharm Biomed Anal ; 203: 114185, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34111734

RESUMO

AIM: We developed a generic high-performance liquid chromatography mass spectrometry approach for quantitation of small molecule compounds without availability of isotopically labelled standard. METHODS: The assay utilized 50 µL of plasma and offers 8 potential internal standards (IS): acetaminophen, veliparib, busulfan, neratinib, erlotinib, abiraterone, bicalutamide, and paclitaxel. Preparation consisted of acetonitrile protein precipitation and aqueous dilution in a 96 well-plate format. Chromatographic separation was achieved with a Kinetex C18 reverse phase (2.6 µm, 2 mm x 50 mm) column and a gradient of 0.1 % formic acid in acetonitrile and water over an 8 min run time. Mass spectrometric detection was performed on an AB SCIEX4000QTRAP with electrospray, positive-mode ionization. Performance of the generic approach was evaluated with seven drugs (LMP744, olaparib, cabozantinib, triapine, ixabepilone, berzosertib, eribulin) for which validated assays were available. RESULTS: The 8 IS covered a range of polarity, size, and ionization; eluted over the range of chromatographic retention times; were quantitatively extracted; and suffered limited matrix effects. The generic approach proved to be linear for test drugs evaluated over at least 3 orders of magnitude starting at 1-10 ng/mL, with extension of assay ranges with analyte isotopologue MRM channels. At a bias of less than 16 % and precision within 15 %, the assay performance was acceptable. CONCLUSION: The generic approach has become a useful tool to further define the pharmacology of drugs studied in our laboratory and may be utilized as described, or as starting point to develop drug-specific assays with more extensive performance characterization.


Assuntos
Preparações Farmacêuticas , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Técnicas de Diluição do Indicador , Reprodutibilidade dos Testes
7.
Invest New Drugs ; 39(6): 1577-1586, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34180036

RESUMO

The vascular endothelial growth factor (VEGF)/VEGFR and hepatocyte growth factor (HGF)/c-MET signaling pathways act synergistically to promote angiogenesis. Studies indicate VEGF inhibition leads to increased levels of phosphorylated c-MET, bypassing VEGF-mediated angiogenesis and leading to chemoresistance. We conducted a phase 1 clinical trial with 32 patients with refractory solid tumors to evaluate the safety, pharmacokinetics, and pharmacodynamics of combinations of VEGF-targeting pazopanib and the putative c-MET inhibitor ARQ197 (tivantinib) at 5 dose levels (DLs). Patients either took pazopanib and tivantinib from treatment initiation (escalation phase) or pazopanib alone for 7 days, with paired tumor sampling, prior to starting combination treatment (expansion phase). Hypertension was the most common adverse event. No more than 1 dose limiting toxicity (DLT) occurred at any DL, so the maximum tolerated dose (MTD) was not determined; DL5 (800 mg pazopanib daily and 360 mg tivantinib BID) was used during the expansion phase. Twenty of 31 evaluable patients achieved stable disease lasting up to 22 cycles. Circulating VEGF, VEGFR2, HGF, and c-MET levels were assessed, and only VEGF levels increased. Tumor c-MET levels (total and phosphorylated) were determined in paired biopsies before and after 7 days of pazopanib treatment. Total intact c-MET decreased in 6 of 7 biopsy pairs, in contrast to previously reported c-MET elevation in response to VEGF inhibition. These results are discussed in the context of our previously reported analysis of epithelial-mesenchymal transition in these tumors.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Indazóis/uso terapêutico , Neoplasias/tratamento farmacológico , Pirimidinas/uso terapêutico , Pirrolidinonas/uso terapêutico , Quinolinas/uso terapêutico , Sulfonamidas/uso terapêutico , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/efeitos adversos , Inibidores da Angiogênese/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica , Área Sob a Curva , Relação Dose-Resposta a Droga , Esquema de Medicação , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Indazóis/administração & dosagem , Indazóis/efeitos adversos , Indazóis/farmacocinética , Dose Máxima Tolerável , Pessoa de Meia-Idade , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Pirimidinas/administração & dosagem , Pirimidinas/efeitos adversos , Pirimidinas/farmacocinética , Pirrolidinonas/administração & dosagem , Pirrolidinonas/efeitos adversos , Pirrolidinonas/farmacocinética , Quinolinas/administração & dosagem , Quinolinas/efeitos adversos , Quinolinas/farmacocinética , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos , Sulfonamidas/farmacocinética , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos
8.
Mol Cancer Ther ; 20(4): 749-760, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33536190

RESUMO

Ras/Raf/MEK/ERK (MAPK) and PI3K/AKT signaling pathways influence several cell functions involved in oncogenesis, making them attractive drug targets. We describe a novel multiplex immunoassay to quantitate isoform-specific phosphorylation of proteins in the PI3K/AKT and MAPK pathways as a tool to assess pharmacodynamic changes. Isoform-specific assays measuring total protein and site-specific phosphorylation levels of ERK1/2, MEK1/2, AKT1/2/3, and rpS6 were developed on the Luminex platform with validated antibody reagents. The multiplex assay demonstrated satisfactory analytic performance. Fit-for-purpose validation was performed with xenograft models treated with selected agents. In PC3 and HCC70 xenograft tumors, the PI3Kß inhibitor AZD8186 suppressed phosphorylation of AKT1, AKT2, and rpS6 for 4 to 7 hours post single dose, but levels returned to baseline by 24 hours. AKT3 phosphorylation was suppressed in PC3 xenografts at all doses tested, but only at the highest dose in HCC70. The AKT inhibitor MK-2206 reduced AKT1/2/3 phosphorylation in SW620 xenograft tumors 2 to 4 hours postdose, and the MEK inhibitor selumetinib reduced MEK1/2 and ERK1/2 phosphorylation by up to 50% and >90%, respectively. Clinical utility was demonstrated by analyzing biopsies from untreated patients with plexiform neurofibromas enrolled in a clinical trial of selumetinib (NCT02407405). These biopsies showed MEK and ERK phosphorylation levels sufficient for measuring up to 90% inhibition, and low AKT and rpS6 phosphorylation. This validated multiplex immunoassay demonstrates the degree and duration of phosphorylation modulation for three distinct classes of drugs targeting the PI3K/AKT and MAPK pathways.


Assuntos
Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Feminino , Humanos , Camundongos , Camundongos Nus , Fosforilação , Isoformas de Proteínas , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Cancer Res ; 80(2): 304-318, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31732654

RESUMO

The significance of the phenotypic plasticity afforded by epithelial-mesenchymal transition (EMT) for cancer progression and drug resistance remains to be fully elucidated in the clinic. We evaluated epithelial-mesenchymal phenotypic characteristics across a range of tumor histologies using a validated, high-resolution digital microscopic immunofluorescence assay (IFA) that incorporates ß-catenin detection and cellular morphology to delineate carcinoma cells from stromal fibroblasts and that quantitates the individual and colocalized expression of the epithelial marker E-cadherin (E) and the mesenchymal marker vimentin (V) at subcellular resolution ("EMT-IFA"). We report the discovery of ß-catenin+ cancer cells that coexpress E-cadherin and vimentin in core-needle biopsies from patients with various advanced metastatic carcinomas, wherein these cells are transitioning between strongly epithelial and strongly mesenchymal-like phenotypes. Treatment of carcinoma models with anticancer drugs that differ in their mechanism of action (the tyrosine kinase inhibitor pazopanib in MKN45 gastric carcinoma xenografts and the combination of tubulin-targeting agent paclitaxel with the BCR-ABL inhibitor nilotinib in MDA-MB-468 breast cancer xenografts) caused changes in the tumor epithelial-mesenchymal character. Moreover, the appearance of partial EMT or mesenchymal-like carcinoma cells in MDA-MB-468 tumors treated with the paclitaxel-nilotinib combination resulted in upregulation of cancer stem cell (CSC) markers and susceptibility to FAK inhibitor. A metastatic prostate cancer patient treated with the PARP inhibitor talazoparib exhibited similar CSC marker upregulation. Therefore, the phenotypic plasticity conferred on carcinoma cells by EMT allows for rapid adaptation to cytotoxic or molecularly targeted therapy and could create a form of acquired drug resistance that is transient in nature. SIGNIFICANCE: Despite the role of EMT in metastasis and drug resistance, no standardized assessment of EMT phenotypic heterogeneity in human carcinomas exists; the EMT-IFA allows for clinical monitoring of tumor adaptation to therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma/tratamento farmacológico , Plasticidade Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Animais , Antígenos CD/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/metabolismo , Biópsia com Agulha de Grande Calibre , Caderinas/metabolismo , Carcinoma/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Indazóis , Masculino , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Vimentina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/metabolismo
10.
Front Endocrinol (Lausanne) ; 11: 628079, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33679610

RESUMO

A huge diversification of phospholipids, forming the aqueous interfaces of all biomembranes, cannot be accommodated within a simple concept of their role as membrane building blocks. Indeed, a number of signaling functions of (phospho)lipid molecules has been discovered. Among these signaling lipids, a particular group of oxygenated polyunsaturated fatty acids (PUFA), so called lipid mediators, has been thoroughly investigated over several decades. This group includes oxygenated octadecanoids, eicosanoids, and docosanoids and includes several hundreds of individual species. Oxygenation of PUFA can occur when they are esterified into major classes of phospholipids. Initially, these events have been associated with non-specific oxidative injury of biomembranes. An alternative concept is that these post-synthetically oxidatively modified phospholipids and their adducts with proteins are a part of a redox epiphospholipidome that represents a rich and versatile language for intra- and inter-cellular communications. The redox epiphospholipidome may include hundreds of thousands of individual molecular species acting as meaningful biological signals. This review describes the signaling role of oxygenated phospholipids in programs of regulated cell death. Although phospholipid peroxidation has been associated with almost all known cell death programs, we chose to discuss enzymatic pathways activated during apoptosis and ferroptosis and leading to peroxidation of two phospholipid classes, cardiolipins (CLs) and phosphatidylethanolamines (PEs). This is based on the available LC-MS identification and quantitative information on the respective peroxidation products of CLs and PEs. We focused on molecular mechanisms through which two proteins, a mitochondrial hemoprotein cytochrome c (cyt c), and non-heme Fe lipoxygenase (LOX), change their catalytic properties to fulfill new functions of generating oxygenated CL and PE species. Given the high selectivity and specificity of CL and PE peroxidation we argue that enzymatic reactions catalyzed by cyt c/CL complexes and 15-lipoxygenase/phosphatidylethanolamine binding protein 1 (15LOX/PEBP1) complexes dominate, at least during the initiation stage of peroxidation, in apoptosis and ferroptosis. We contrast cell-autonomous nature of CLox signaling in apoptosis correlating with its anti-inflammatory functions vs. non-cell-autonomous ferroptotic signaling facilitating pro-inflammatory (necro-inflammatory) responses. Finally, we propose that small molecule mechanism-based regulators of enzymatic phospholipid peroxidation may lead to highly specific anti-apoptotic and anti-ferroptotic therapeutic modalities.


Assuntos
Apoptose/fisiologia , Ácidos Graxos Insaturados/metabolismo , Lipidômica/métodos , Fosfolipídeos/metabolismo , Transdução de Sinais/fisiologia , Animais , Catálise , Morte Celular/fisiologia , Ferroptose/fisiologia , Humanos , Oxirredução
11.
J Exp Ther Oncol ; 13(1): 9-14, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30658021

RESUMO

BACKGROUND: Periodontal diseases are of microbial etiology and are globally causing loss of teeth in adult population. Many severe oral diseases have been recently associated to Herpes viruses, of which Epstein Barr Virus (EBV) and human cytomegalovirus (HCMV) have been indicated in the etiology of periodontal diseases. AIM: The purpose of the study was to compare the effect of EBV in different types of periodontal diseases namely acute gingivitis, chronic gingivitis, acute and chronic, localized and generalized aggressive (juvenile) periodontitis and apical periodontitis. MATERIAL AND METHOD: 70 individuals were included in this study. Supragingival plaque and plaque from two deepest sites of the periodontal pockets were collected then stored at 70° c and prepared for nucleic acid extraction. For EBV detection, DNA were extracted from the plaque samples with the QIAamp DNA mini kit. Q-PCR was performed by targeting the non-polymorphic Epstein-Barr nuclear antigen-1 (EBNA-1) gene using Corbett Research 6000 Q-PCR instrument and Rotor gene 6000 software. RESULTS: Overall prevalence of EBV in the disease group was 60% (27/45 patients) as compared to only 8% (4/25 people) in the normal population. The mean copy number of EBV DNA was found to be significantly higher in periodontitis (2234 ± 1811.34) when compared to gingivitis (554 ± 537.64, p = .001) and normal patients (370 ± 161.03, p < .001). CONCLUSION: Here, we found that the prevalence of EBV as well as copy number of EBV was significantly higher in periodontitis patients as compared to gingivitis patients or normal population.


Assuntos
Gengivite , Herpesvirus Humano 4 , Periodontite , Adulto , Citomegalovirus , Gengivite/virologia , Herpesvirus Humano 4/isolamento & purificação , Humanos , Bolsa Periodontal , Periodontite/virologia
12.
Oman Med J ; 33(5): 401-408, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30210719

RESUMO

OBJECTIVES: Obesity increases the risk of numerous chronic diseases. Obesity is classified clinically using body mass index (BMI), waist-to-hip ratio, and body fat percentage. The lipoprotein lipase (LPL) gene has been linked to lipoprotein metabolism and obesity. We performed a case-control study to determine the association between LPL gene polymorphisms and obesity-associated phenotypes such as insulin resistance (IR). METHODS: We examined the different LPL gene variants for association in 642 individuals segregated by BMI and IR. Genotyping of the LPL gene -93 and -53 promoter gene polymorphisms were analyzed using polymerase chain reaction-restriction fragment length polymorphism. RESULTS: A substantial association was observed for -93 gene polymorphism of the LPL gene with obesity, while -53 promoter gene polymorphism showed association with IR. CONCLUSIONS: We found a significant association between -93 and -53 promoter gene polymorphisms of the LPL gene with obesity and associated phenotypes in the studied population.

13.
Mol Cancer Ther ; 17(3): 698-709, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29444985

RESUMO

The development of molecularly targeted agents has benefited from use of pharmacodynamic markers to identify "biologically effective doses" (BED) below MTDs, yet this knowledge remains underutilized in selecting dosage regimens and in comparing the effectiveness of targeted agents within a class. We sought to establish preclinical proof-of-concept for such pharmacodynamics-based BED regimens and effectiveness comparisons using MET kinase small-molecule inhibitors. Utilizing pharmacodynamic biomarker measurements of MET signaling (tumor pY1234/1235MET/total MET ratio) in a phase 0-like preclinical setting, we developed optimal dosage regimens for several MET kinase inhibitors and compared their antitumor efficacy in a MET-amplified gastric cancer xenograft model (SNU-5). Reductions in tumor pY1234/1235MET/total MET of 95%-99% were achievable with tolerable doses of EMD1214063/MSC2156119J (tepotinib), XL184 (cabozantinib), and XL880/GSK1363089 (foretinib), but not ARQ197 (tivantinib), which did not alter the pharmacodynamic biomarker. Duration of kinase suppression and rate of kinase recovery were specific to each agent, emphasizing the importance of developing customized dosage regimens to achieve continuous suppression of the pharmacodynamic biomarker at the required level (here, ≥90% MET kinase suppression). The customized dosage regimen of each inhibitor yielded substantial and sustained tumor regression; the equivalent effectiveness of customized dosage regimens that achieve the same level of continuous molecular target control represents preclinical proof-of-concept and illustrates the importance of proper scheduling of targeted agent BEDs. Pharmacodynamics-guided biologically effective dosage regimens (PD-BEDR) potentially offer a superior alternative to pharmacokinetic guidance (e.g., drug concentrations in surrogate tissues) for developing and making head-to-head comparisons of targeted agents. Mol Cancer Ther; 17(3); 698-709. ©2018 AACR.


Assuntos
Desenvolvimento de Medicamentos/métodos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Neoplasias Gástricas/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto , Anilidas/farmacologia , Animais , Linhagem Celular Tumoral , Humanos , Camundongos Nus , Inibidores de Proteínas Quinases/farmacocinética , Proteínas Proto-Oncogênicas c-met/metabolismo , Piridazinas/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Quinolinas/farmacologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos
14.
PLoS One ; 12(8): e0182739, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28771597

RESUMO

Cancer therapies can provide substantially improved survival in some patients while other seemingly similar patients receive little or no benefit. Strategies to identify patients likely to respond well to a given therapy could significantly improve health care outcomes by maximizing clinical benefits while reducing toxicities and adverse effects. Using a glycan microarray assay, we recently reported that pretreatment serum levels of IgM specific to blood group A trisaccharide (BG-Atri) correlate positively with overall survival of cancer patients on PROSTVAC-VF therapy. The results suggested anti-BG-Atri IgM measured prior to treatment could serve as a biomarker for identifying patients likely to benefit from PROSTVAC-VF. For continued development and clinical application of serum IgM specific to BG-Atri as a predictive biomarker, a clinical assay was needed. In this study, we developed and validated a Luminex-based clinical assay for measuring serum IgM specific to BG-Atri. IgM levels were measured with the Luminex assay and compared to levels measured using the microarray for 126 healthy individuals and 77 prostate cancer patients. This assay provided reproducible and consistent results with low %CVs, and tolerance ranges were established for the assay. IgM levels measured using the Luminex assay were found to be highly correlated to the microarray results with R values of 0.93-0.95. This assay is a Laboratory Developed Test (LDT) and is suitable for evaluating thousands of serum samples in CLIA certified laboratories that have validated the assay. In addition, the study demonstrates that discoveries made using neoglycoprotein-based microarrays can be readily migrated to a clinical assay.


Assuntos
Vacinas Anticâncer/uso terapêutico , Imunoglobulina M/sangue , Testes Imunológicos/métodos , Oligossacarídeos/imunologia , Neoplasias da Próstata/terapia , Sistema ABO de Grupos Sanguíneos , Biomarcadores/metabolismo , Humanos , Masculino , Oligossacarídeos de Cadeias Ramificadas , Polissacarídeos/metabolismo , Neoplasias da Próstata/imunologia , Análise Serial de Proteínas , Análise de Sobrevida , Resultado do Tratamento
15.
Cancer Res ; 77(13): 3564-3576, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28446463

RESUMO

To date, over 100 small-molecule oncology drugs have been approved by the FDA. Because of the inherent heterogeneity of tumors, these small molecules are often administered in combination to prevent emergence of resistant cell subpopulations. Therefore, new combination strategies to overcome drug resistance in patients with advanced cancer are needed. In this study, we performed a systematic evaluation of the therapeutic activity of over 5,000 pairs of FDA-approved cancer drugs against a panel of 60 well-characterized human tumor cell lines (NCI-60) to uncover combinations with greater than additive growth-inhibitory activity. Screening results were compiled into a database, termed the NCI-ALMANAC (A Large Matrix of Anti-Neoplastic Agent Combinations), publicly available at https://dtp.cancer.gov/ncialmanac Subsequent in vivo experiments in mouse xenograft models of human cancer confirmed combinations with greater than single-agent efficacy. Concomitant detection of mechanistic biomarkers for these combinations in vivo supported the initiation of two phase I clinical trials at the NCI to evaluate clofarabine with bortezomib and nilotinib with paclitaxel in patients with advanced cancer. Consequently, the hypothesis-generating NCI-ALMANAC web-based resource has demonstrated value in identifying promising combinations of approved drugs with potent anticancer activity for further mechanistic study and translation to clinical trials. Cancer Res; 77(13); 3564-76. ©2017 AACR.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , National Cancer Institute (U.S.) , Estados Unidos , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Ann Transl Med ; 5(1): 3, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28164088

RESUMO

MET tyrosine kinase (TK) dysregulation is significantly implicated in many types of cancer. Despite over 20 years of drug development to target MET in cancers, a pure anti-MET therapeutic has not yet received market approval. The failure of two recently concluded phase III trials point to a major weakness in biomarker strategies to identify patients who will benefit most from MET therapies. The capability to interrogate oncogenic mutations in MET via circulating tumor DNA (ctDNA) provides an important advancement in identification and stratification of patients for MET therapy. However, a wide range in type and frequency of these mutations suggest there is a need to carefully link these mutations to MET dysregulation, at least in proof-of-concept studies. In this review, we elaborate how we can utilize recently developed and validated pharmacodynamic biomarkers of MET not only to show target engagement, but more importantly to quantitatively measure MET dysregulation in tumor tissues. The MET assay endpoints provide evidence of both canonical and non-canonical MET signaling, can be used as "effect markers" to define biologically effective doses (BEDs) for molecularly targeted drugs, confirm mechanism-of-action in testing combination of drugs, and establish whether a diagnostic test is reporting MET dysregulation. We have established standard operating procedures for tumor biopsy collections to control pre-analytical variables that have produced valid results in proof-of-concept studies. The reagents and procedures are made available to the research community for potential implementation on multiple platforms such as ELISA, quantitative immunofluorescence assay (qIFA), and immuno-MRM assays.

17.
Am J Hum Biol ; 29(2)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27650258

RESUMO

OBJECTIVES: The aim of the study was to investigate the association of 55 SNPs in 28 genes with obesity risk in a North Indian population using a multianalytical approach. METHODS: Overall, 480 subjects from the North Indian population were studied using strict inclusion/exclusion criteria. SNP Genotyping was carried out by Sequenom Mass ARRAY platform (Sequenom, San Diego, CA) and validated Taqman® allelic discrimination (Applied Biosystems® ). Statistical analyses were performed using SPSS software version 19.0, SNPStats, GMDR software (version 6) and GENEMANIA. RESULTS: Logistic regression analysis of 55 SNPs revealed significant associations (P < .05) of 49 SNPs with BMI linked obesity risk whereas the remaining 6 SNPs revealed no association (P > .05). The pathway-wise G-score revealed the significant role (P = .0001) of food intake-energy expenditure pathway genes. In CART analysis, the combined genotypes of FTO rs9939609 and TCF7L2 rs7903146 revealed the highest risk for BMI linked obesity. The analysis of the FTO-IRX3 locus revealed high LD and high order gene-gene interactions for BMI linked obesity. The interaction network of all of the associated genes in the present study generated by GENEMANIA revealed direct and indirect connections. In addition, the analysis with centralized obesity revealed that none of the SNPs except for FTO rs17818902 were significantly associated (P < .05). CONCLUSIONS: In this multi-analytical approach, FTO rs9939609 and IRX3 rs3751723, along with TCF7L2 rs7903146 and TMEM18 rs6548238, emerged as the major SNPs contributing to BMI linked obesity risk in the North Indian population.


Assuntos
Obesidade/genética , Polimorfismo de Nucleotídeo Único , Adulto , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Índia , Masculino , Risco , Adulto Jovem
18.
Indian J Clin Biochem ; 31(4): 361-71, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27605733

RESUMO

Numerous classical genetic studies have proved that genes are contributory factors for obesity. Genes are directly responsible for obesity associated disorders such as Bardet-Biedl and Prader-Willi syndromes. However, both genes as well as environment are associated with obesity in the general population. Genetic epidemiological approaches, particularly genome-wide association studies, have unraveled many genes which play important roles in human obesity. Elucidation of their biological functions can be very useful for understanding pathobiology of obesity. In the near future, further exploration of obesity genetics may help to develop useful diagnostic and predictive tests for obesity treatment.

20.
Oman Med J ; 31(2): 99-106, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27168919

RESUMO

OBJECTIVES: Obesity is a common disorder that has a significant impact on morbidity and mortality. Twin and adoption studies support the genetic influence on variation of obesity, and the estimates of the heritability of body mass index (BMI) is significantly high (30 to 70%). Variants in the fat mass and obesity-associated (FTO) gene have been associated with obesity and obesity-related phenotypes in different populations. The aim of this study was to examine the association of FTO rs9939609 with obesity and related phenotypes in North Indian subjects. . METHODS: Gene variants were investigated for association with obesity in 309 obese and 333 non-obese patients. Genotyping of the FTO rs9939609 single nucleotide polymorphism (SNP) was analyzed using Restriction Fragment Length Polymorphism Analysis of PCR-Amplified Fragments. We also measured participants fasting glucose and insulin levels, lipid profile, percentage body fat, fat mass and fat free mass. . RESULTS: Waist to hip ratio, systolic blood pressure, diastolic blood pressure, percentage body fat, fat mass, insulin concentration, and homeostasis model assessment index (HOMA-Index) showed a significant difference between the study groups. Significant associations were found for FTO rs9939609 SNP with obesity and obesity-related phenotypes. The significant associations were observed between the rs9939609 SNP and blood pressure, fat mass, insulin, and HOMA-index under a different model. . CONCLUSION: This study presents significant association between FTO rs9939609 and obesity defined by BMI and also established the strong association with several measures of obesity in North Indian population.

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