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1.
Sci Transl Med ; 15(678): eabm6863, 2023 01 11.
Article de Anglais | MEDLINE | ID: mdl-36630480

RÉSUMÉ

Genome-wide fragmentation patterns in cell-free DNA (cfDNA) in plasma are strongly influenced by cellular origin due to variation in chromatin accessibility across cell types. Such differences between healthy and cancer cells provide the opportunity for development of novel cancer diagnostics. Here, we investigated whether analysis of cfDNA fragment end positions and their surrounding DNA sequences reveals the presence of tumor-derived DNA in blood. We performed genome-wide analysis of cfDNA from 521 samples and analyzed sequencing data from an additional 2147 samples, including healthy individuals and patients with 11 different cancer types. We developed a metric based on genome-wide differences in fragment positioning, weighted by fragment length and GC content [information-weighted fraction of aberrant fragments (iwFAF)]. We observed that iwFAF strongly correlated with tumor fraction, was higher for DNA fragments carrying somatic mutations, and was higher within genomic regions affected by copy number amplifications. We also calculated sample-level means of nucleotide frequencies observed at genomic positions spanning fragment ends. Using a combination of iwFAF and nine nucleotide frequencies from three positions surrounding fragment ends, we developed a machine learning model to differentiate healthy individuals from patients with cancer. We observed an area under the receiver operative characteristic curve (AUC) of 0.91 for detection of cancer at any stage and an AUC of 0.87 for detection of stage I cancer. Our findings remained robust with as few as 1 million fragments analyzed per sample, demonstrating that analysis of fragment ends can become a cost-effective and accessible approach for cancer detection and monitoring.


Sujet(s)
Acides nucléiques acellulaires , Tumeurs , Humains , ADN/génétique , Tumeurs/génétique , Chromatine , Nucléotides , Marqueurs biologiques tumoraux/génétique , Analyse de séquence d'ADN
2.
Hepatology ; 75(1): 43-58, 2022 01.
Article de Anglais | MEDLINE | ID: mdl-34407567

RÉSUMÉ

BACKGROUND AND AIMS: Biliary tract cancers (BTCs) are uncommon, but highly lethal, gastrointestinal malignancies. Gemcitabine/cisplatin is a standard-of-care systemic therapy, but has a modest impact on survival and harbors toxicities, including myelosuppression, nephropathy, neuropathy, and ototoxicity. Whereas BTCs are characterized by aberrations activating the cyclinD1/cyclin-dependent kinase (CDK)4/6/CDK inhibitor 2a/retinoblastoma pathway, clinical use of CDK4/6 inhibitors as monotherapy is limited by lack of validated biomarkers, diffident preclinical efficacy, and development of acquired drug resistance. Emerging studies have explored therapeutic strategies to enhance the antitumor efficacy of CDK4/6 inhibitors by the combination with chemotherapy regimens, but their mechanism of action remains elusive. APPROACH AND RESULTS: Here, we report in vitro and in vivo synergy in BTC models, showing enhanced efficacy, reduced toxicity, and better survival with a combination comprising gemcitabine/cisplatin and CDK4/6 inhibitors. Furthermore, we demonstrated that abemaciclib monotherapy had only modest efficacy attributable to autophagy-induced resistance. Notably, triplet therapy was able to potentiate efficacy through elimination of the autophagic flux. Correspondingly, abemaciclib potentiated ribonucleotide reductase catalytic subunit M1 reduction, resulting in sensitization to gemcitabine. CONCLUSIONS: As such, these data provide robust preclinical mechanistic evidence of synergy between gemcitabine/cisplatin and CDK4/6 inhibitors and delineate a path forward for translation of these findings to preliminary clinical studies in advanced BTC patients.


Sujet(s)
Protocoles de polychimiothérapie antinéoplasique/pharmacologie , Tumeurs des voies biliaires/traitement médicamenteux , Inhibiteurs de protéines kinases/pharmacologie , Animaux , Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Autophagie/effets des médicaments et des substances chimiques , Tumeurs des voies biliaires/mortalité , Tumeurs des voies biliaires/anatomopathologie , Cisplatine/pharmacologie , Cisplatine/usage thérapeutique , Kinase-4 cycline-dépendante/antagonistes et inhibiteurs , Kinase-6 cycline-dépendante/antagonistes et inhibiteurs , Désoxycytidine/analogues et dérivés , Désoxycytidine/pharmacologie , Désoxycytidine/usage thérapeutique , Synergie des médicaments , Humains , Souris , Inhibiteurs de protéines kinases/usage thérapeutique , Tests d'activité antitumorale sur modèle de xénogreffe ,
3.
Prostate Cancer Prostatic Dis ; 25(3): 479-483, 2022 09.
Article de Anglais | MEDLINE | ID: mdl-34294873

RÉSUMÉ

BACKGROUND: Altered tumor suppressor genes (TSG-alt) in prostate cancer are associated with worse outcomes. The prognostic value of TSG-alt in metastatic, hormone-sensitive prostate cancer (M1-HSPC) is unknown. We evaluated the effects of TSG-alt on outcomes in M1-HSPC and their prognostic impact by first-line treatment. METHODS: We retrospectively identified patients with M1-HSPC at our institution treated with first-line androgen deprivation therapy plus docetaxel (ADT + D) or abiraterone acetate (ADT + A). TSG-alt was defined as any alteration in one or more TSG. The main outcomes were Kaplan-Meier-estimated progression-free survival (PFS) and overall survival, analyzed with the log-rank test. Clinical characteristics were compared with the χ2 test and Kruskal-Wallis rank sum test. Cox regression was used for univariate and multivariable analyses. RESULTS: We identified 97 patients with M1-HSPC: 48 (49%) with ADT + A and 49 (51%) with ADT + D. Of 96 patients with data available, 33 (34%) had 1 TSG-alt, 16 (17%) had 2 TSG-alt, and 2 (2%) had 3 TSG-alt. The most common alterations were in TP53 (36%) and PTEN (31%); 6% had RB1 alterations. Median PFS was 13.1 (95% CI, 10.3-26.0) months for patients with normal TSGs (TSG-normal) vs. 7.8 (95% CI, 5.8-10.5) months for TSG-alt (P = 0.005). Median PFS was lower for patients with TSG-alt vs TSG-normal for those with ADT + A (TSG-alt: 8.0 [95% CI, 5.8-13.8] months vs. TSG-normal: 23.2 [95% CI, 13.1-not estimated] months), but not with ADT + D (TSG-alt: 7.8 [95% CI, 5.7-12.9] months vs. TSG-normal: 9.5 [95% CI, 4.8-24.7] months). On multivariable analysis, only TSG-alt predicted worse PFS (hazard ratio, 2.37; 95% CI, 1.42-3.96; P < 0.001). CONCLUSIONS: The presence of TSG-alt outperforms clinical criteria for predicting early progression during first-line treatment of M1-HSPC. ADT + A was less effective in patients with than without TSG-alt. Confirmation of these findings may establish the need for inclusion of molecular stratification in treatment algorithms.


Sujet(s)
Tumeurs de la prostate , Antagonistes des androgènes , Docetaxel , Gènes suppresseurs de tumeur , Hormones/usage thérapeutique , Humains , Mâle , Phosphohydrolase PTEN/génétique , Tumeurs de la prostate/traitement médicamenteux , Tumeurs de la prostate/génétique , Tumeurs de la prostate/anatomopathologie , Protéines de liaison à la protéine du rétinoblastome/génétique , Études rétrospectives , Résultat thérapeutique , Protéine p53 suppresseur de tumeur/génétique , Ubiquitin-protein ligases/génétique
4.
PLoS One ; 16(5): e0250518, 2021.
Article de Anglais | MEDLINE | ID: mdl-34033669

RÉSUMÉ

Gestational trophoblastic disease (GTD) is a heterogeneous group of lesions arising from placental tissue. Epithelioid trophoblastic tumor (ETT), derived from chorionic-type trophoblast, is the rarest form of GTD with only approximately 130 cases described in the literature. Due to its morphologic mimicry of epithelioid smooth muscle tumors and carcinoma, ETT can be misdiagnosed. To date, molecular characterization of ETTs is lacking. Furthermore, ETT is difficult to treat when disease spreads beyond the uterus. Here using RNA-Seq analysis in a cohort of ETTs and other gestational trophoblastic lesions we describe the discovery of LPCAT1-TERT fusion transcripts that occur in ETTs and coincide with underlying genomic deletions. Through cell-growth assays we demonstrate that LPCAT1-TERT fusion proteins can positively modulate cell proliferation and therefore may represent future treatment targets. Furthermore, we demonstrate that TERT upregulation appears to be a characteristic of ETTs, even in the absence of LPCAT1-TERT fusions, and that it appears linked to copy number gains of chromosome 5. No evidence of TERT upregulation was identified in other trophoblastic lesions tested, including placental site trophoblastic tumors and placental site nodules, which are thought to be the benign chorionic-type trophoblast counterpart to ETT. These findings indicate that LPCAT1-TERT fusions and copy-number driven TERT activation may represent novel markers for ETT, with the potential to improve the diagnosis, treatment, and outcome for women with this rare form of GTD.


Sujet(s)
1-Acylglycerophosphocholine acyltransferase/génétique , Cellules épithélioïdes/anatomopathologie , Maladie trophoblastique gestationnelle/étiologie , Protéines de fusion oncogènes/génétique , Telomerase/génétique , Tumeurs trophoblastiques/anatomopathologie , Tumeurs de l'utérus/anatomopathologie , 1-Acylglycerophosphocholine acyltransferase/métabolisme , Adulte , Marqueurs biologiques tumoraux/génétique , Prolifération cellulaire , Cellules épithélioïdes/métabolisme , Femelle , Maladie trophoblastique gestationnelle/anatomopathologie , Humains , Adulte d'âge moyen , Protéines de fusion oncogènes/métabolisme , Grossesse , Telomerase/métabolisme , Tumeurs trophoblastiques/génétique , Tumeurs trophoblastiques/métabolisme , Tumeurs de l'utérus/génétique , Tumeurs de l'utérus/métabolisme
5.
Prostate ; 81(7): 433-439, 2021 05.
Article de Anglais | MEDLINE | ID: mdl-33792945

RÉSUMÉ

BACKGROUND: The goal of this study is to evaluate germline genetic variants in African American men with metastatic prostate cancer as compared to those in Caucasian men with metastatic prostate cancer in an effort to understand the role of genetic factors in these populations. METHODS: African American and Caucasian men with metastatic prostate cancer who had germline testing using multigene panels were used to generate comparisons. Germline genetic results, clinical parameters, and family histories between the two populations were analyzed. RESULTS: A total of 867 patients were included in this retrospective study, including 188 African American and 669 Caucasian patients. There was no significant difference in the likelihood of a pathogenic or likely-pathogenic variants (PV/LPVs) between African American and Caucasian patients (p = .09). African American patients were more likely to have a variant of unknown significance than Caucasians (odds ratio [OR] = 1.95; p < .0001). BRCA1 PV/LPVs were higher in African Americans (OR = 4.86; p = .04). African American patients were less likely to have a PV/LPV in non-BRCA DNA repair genes (OR = 0.30; p = .008). Family history of breast (OR = 2.09; p = .002) or ovarian cancer (OR = 2.33; p = .04) predicted PV/LPVs in Caucasians but not African-Americans. This underscores the limitations of family history in AA men and the importance of personal history to guide germline testing in AA men. CONCLUSIONS: In metastatic prostate cancer patients, PV/LPVs of tested genes did not vary by race, BRCA1 PV/LPVs were more common in the African American subset. However, PV/LPVs in non-BRCA DNA repair genes were less likely to be encountered in African Americans. Family history associated with genetic testing results in Caucasians only.


Sujet(s)
Protéine BRCA2/génétique , /génétique , Mutation germinale , Métastase tumorale/génétique , Tumeurs de la prostate/génétique , /génétique , Humains , Mâle , Adulte d'âge moyen , Métastase tumorale/anatomopathologie , Tumeurs de la prostate/anatomopathologie
6.
AMIA Jt Summits Transl Sci Proc ; 2020: 750-759, 2020.
Article de Anglais | MEDLINE | ID: mdl-32477698

RÉSUMÉ

Phenome Wide Association Studies (PheWAS) enables phenome-wide scans to discover novel associations between genotype and clinical phenotypes via linking available genomic reports and large-scale Electronic Health Record (EHR). Data heterogeneity from different EHR systems and genetic reports has been a critical challenge that hinders meaningful validation. To address this, we propose an FHIR-based framework to model the PheWAS study in a standard manner. We developed an FHIR-based data model profile to enable the standard representation of data elements from genetic reports and EHR data that are used in the PheWAS study. As a proof-of-concept, we implemented the proposed method using a cohort of 1,595 pan-cancer patients with genetic reports from Foundation Medicine as well as the corresponding lab tests and diagnosis from Mayo EHRs. A PheWAS study is conducted and 81 significant genotype-phenotype associations are identified, in which 36 significant associations for cancers are validated based on a literature review.

7.
Cancer Chemother Pharmacol ; 85(6): 1063-1078, 2020 06.
Article de Anglais | MEDLINE | ID: mdl-32440762

RÉSUMÉ

PURPOSE: NUC1031 is a first-in-class ProTide, that is a gemcitabine pro-drug designed to overcome putative mechanisms of resistance, including decreased expression of hENT/hCNT transporters, absence of activating enzymes such as deoxycytidine kinase (dCK) and presence of degrading enzymes such as cytidine deaminase (CDA). We undertook comprehensive pre-clinical evaluation of NUC1031 in biliary tract cancer (BTC) models, given that gemcitabine/cisplatin is a standard first-line therapy in advanced BTC. METHODS: Here, we compared the in vitro activity of NUC1031 in comparison to gemcitabine, validate putative mechanism(s) of action, assessed potential biomarkers of sensitivity or resistance, and performed combination studies with cisplatin. We also evaluated the in vivo efficacy of NUC1031 and gemcitabine using a CDA-high cholangiocarcinoma patient-derived xenograft (PDX) model. RESULTS: In a panel of BTC cell lines (N = 10), NUC1031 had less potency than gemcitabine in multiple cellular assays. NUC1031 did not demonstrate evidence of greater synergy over gemcitabine in combination with cisplatin. Surprisingly, efficacy of both gemcitabine and NUC1031 was not found to be correlated with hENT/hCTN, dCK or CDA transcript levels. Gemcitabine and NUC1031 showed equivalent efficacy in a CDA-high PDX model in vivo contradicting the primary rationale of NUC1031 design. CONCLUSION: NUC1031 did not exhibit evidence of superior activity over gemcitabine, as a single-agent, or in combination with cisplatin, in either our in vivo or in vitro BTC models. Given that the largest Phase 3 study (ClinicalTrials.gov: NCT0314666) to date in BTC is underway (N = 828) comparing NUC1031/cisplatin to gemcitabine/cisplatin, our results suggest that a more conservative clinical evaluation path would be more appropriate.


Sujet(s)
Protocoles de polychimiothérapie antinéoplasique/pharmacologie , Tumeurs des voies biliaires/traitement médicamenteux , Synergie des médicaments , Animaux , Apoptose , Tumeurs des voies biliaires/anatomopathologie , Prolifération cellulaire , Cisplatine/administration et posologie , Cytidine monophosphate/administration et posologie , Cytidine monophosphate/analogues et dérivés , Désoxycytidine/administration et posologie , Désoxycytidine/analogues et dérivés , Femelle , Humains , Souris , Souris de lignée NOD , Souris SCID , Cellules cancéreuses en culture , Tests d'activité antitumorale sur modèle de xénogreffe ,
8.
Bioinformatics ; 36(6): 1712-1717, 2020 03 01.
Article de Anglais | MEDLINE | ID: mdl-32176769

RÉSUMÉ

MOTIVATION: Functions of cancer driver genes vary substantially across tissues and organs. Distinguishing passenger genes, oncogenes (OGs) and tumor-suppressor genes (TSGs) for each cancer type is critical for understanding tumor biology and identifying clinically actionable targets. Although many computational tools are available to predict putative cancer driver genes, resources for context-aware classifications of OGs and TSGs are limited. RESULTS: We show that the direction and magnitude of somatic selection of protein-coding mutations are significantly different for passenger genes, OGs and TSGs. Based on these patterns, we develop a new method (genes under selection in tumors) to discover OGs and TSGs in a cancer-type specific manner. Genes under selection in tumors shows a high accuracy (92%) when evaluated via strict cross-validations. Its application to 10 172 tumor exomes found known and novel cancer drivers with high tissue-specificities. In 11 out of 13 OGs shared among multiple cancer types, we found functional domains selectively engaged in different cancers, suggesting differences in disease mechanisms. AVAILABILITY AND IMPLEMENTATION: An R implementation of the GUST algorithm is available at https://github.com/liliulab/gust. A database with pre-computed results is available at https://liliulab.shinyapps.io/gust. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Sujet(s)
Gènes suppresseurs de tumeur , Tumeurs/génétique , Algorithmes , Humains , Mutation , Oncogènes
9.
Sci Rep ; 9(1): 3586, 2019 03 05.
Article de Anglais | MEDLINE | ID: mdl-30837548

RÉSUMÉ

Post-pubertal testicular germ-cell tumours (TGCTs) can present with a variety of distinct histologies which are nevertheless lineage related and often co-occurring. The exact lineage relationships and developmental pathways leading to the different histologies is debated. In order to investigate the relationship of histologic populations, mate-pair sequencing (MPseq) and exome sequencing (ExomeSeq) were conducted on different histological populations within the same tumour. Ten TGCTs with 1-3 histologic types/tumour were sequenced. Junctions of somatic chromosomal rearrangements were identified on a per genome basis, with germ cell neoplasia in situ possessing the least (median 1, range 0-4) and embryonal carcinoma the most (median 8.5, range 6-12). Copy number variation revealed gains and losses, including isoform 12p (i12p) (10/10 samples), and chromosomes 7, 8, and 21 gains (7/10 samples). Mapping of shared junctions within a tumour revealed lineage relationships, but only i12p was shared between patients. ExomeSeq from two cases demonstrated a high level of copy-neutral loss of heterozygosity. Parallel assessment of separate histologies within a single TGCT demonstrated cumulative and divergent changes, suggesting the importance of parallel sequencing for detection of relevant biomarkers.


Sujet(s)
Aberrations des chromosomes , ADN tumoral/analyse , Variation structurale du génome , Mutation , Protéines tumorales/génétique , Tumeurs embryonnaires et germinales/classification , Tumeurs embryonnaires et germinales/génétique , Tumeurs du testicule/classification , Tumeurs du testicule/génétique , Adolescent , Adulte , ADN tumoral/génétique , Séquençage nucléotidique à haut débit , Humains , Adulte d'âge moyen , Tumeurs embryonnaires et germinales/anatomopathologie , Tumeurs du testicule/anatomopathologie , Jeune adulte
10.
Hepatology ; 69(1): 131-142, 2019 01.
Article de Anglais | MEDLINE | ID: mdl-30067876

RÉSUMÉ

About 15% of intrahepatic cholangiocarcinomas (ICCs) express constitutively active fibroblast growth factor receptor 2 (FGFR2) fusion proteins (FFs) generated by chromosomal translocations. FFs have been nominated as oncogenic drivers because administration of FGFR tyrosine kinase inhibitors (F-TKIs) can elicit meaningful objective clinical responses in patients carrying FF-positive ICC. Thus, optimization of FF targeting is a pressing clinical need. Herein, we report that three different FFs, previously isolated from ICC samples, are heat shock protein 90 (HSP90) clients and undergo rapid degradation upon HSP90 pharmacological blockade by the clinically advanced HSP90 inhibitor ganetespib. Combining catalytic suppression by the F-TKI BGJ398 with HSP90 blockade by ganetespib suppressed FGFR2-TACC3 (transforming acidic coiled-coil containing protein 3) signaling in cultured cells more effectively than either BGJ398 or ganetespib in isolation. The BGJ398 + ganetespib combo was also superior to single agents when tested in mice carrying subcutaneous tumors generated by transplantation of FGFR2-TACC3 NIH3T3 transformants. Of note, FF mutants known to enforce clinical resistance to BGJ398 in ICC patients retained full sensitivity to ganetespib in cultured cells. Conclusion: Our data provide a proof of principle that upfront treatment with the BGJ398 + ganetespib combo improves therapeutic targeting of FGFR2 fusions in an experimental setting, which may be relevant to precision medicine approaches to FF-driven ICC.


Sujet(s)
Tumeurs des canaux biliaires/traitement médicamenteux , Cholangiocarcinome/traitement médicamenteux , Protéines du choc thermique HSP90/antagonistes et inhibiteurs , Protéines associées aux microtubules/métabolisme , Phénylurées/administration et posologie , Pyrimidines/administration et posologie , Récepteur FGFR2/métabolisme , Triazoles/administration et posologie , Animaux , Cellules cultivées , Association médicamenteuse , Femelle , Humains , Souris
11.
Oncolytic Virother ; 6: 39-49, 2017.
Article de Anglais | MEDLINE | ID: mdl-29184854

RÉSUMÉ

With the advancement of a growing number of oncolytic viruses (OVs) to clinical development, drug delivery is becoming an important barrier to overcome for optimal therapeutic benefits. Host immunity, tumor microenvironment and abnormal vascularity contribute to inefficient vector delivery. A number of novel approaches for enhanced OV delivery are under evaluation, including use of nanoparticles, immunomodulatory agents and complex viral-particle ligands along with manipulations of the tumor microenvironment. This field of OV delivery has quickly evolved to bioengineering of complex nanoparticles that could be deposited within the tumor using minimal invasive image-guided delivery. Some of the strategies include ultrasound (US)-mediated cavitation-enhanced extravasation, magnetic viral complexes delivery, image-guided infusions with focused US and targeting photodynamic virotherapy. In addition, strategies that modulate tumor microenvironment to decrease extracellular matrix deposition and increase viral propagation are being used to improve tumor penetration by OVs. Some involve modification of the viral genome to enhance their tumoral penetration potential. Here, we highlight the barriers to oncolytic viral delivery, and discuss the challenges to improving it and the perspectives of establishing new modes of active delivery to achieve enhanced oncolytic effects.

12.
Oncotarget ; 8(16): 27145-27154, 2017 Apr 18.
Article de Anglais | MEDLINE | ID: mdl-28423702

RÉSUMÉ

BACKGROUND: The ability to analyze the genomics of malignancies has opened up new possibilities for off-label targeted therapy in cancers that are refractory to standard therapy. At Mayo Clinic these efforts are organized through the Center for Individualized Medicine (CIM). RESULTS: Prior to GTB, datasets were analyzed and integrated by a team of bioinformaticians and cancer biologists. Therapeutically actionable mutations were identified in 65% (92/141) of the patients tested with 32% (29/92) receiving genomically targeted therapy with FDA approved drugs or in an independent clinical trial with 45% (13/29) responding. Standard of care (SOC) options were continued by 15% (14/92) of patients tested before exhausting SOC options, with 71% (10/14) responding to treatment. Over 35% (34/92) of patients with actionable targets were not treated with 65% (22/34) choosing comfort measures or passing away. MATERIALS AND METHODS: Patients (N = 165) were referred to the CIM Clinic between October 2012 and December 2015. All patients received clinical genomic panel testing with selected subsets receiving array comparative genomic hybridization and clinical whole exome sequencing to complement and validate panel findings. A genomic tumor board (GTB) reviewed results and, when possible, developed treatment recommendations. CONCLUSIONS: Treatment decisions driven by tumor genomic analysis can lead to significant clinical benefit in a minority of patients. The success of genomically driven therapy depends both on access to drugs and robustness of bioinformatics analysis. While novel clinical trial designs are increasing the utility of genomic testing, robust data sharing of outcomes is needed to optimize clinical benefit for all patients.


Sujet(s)
Marqueurs biologiques tumoraux , Génomique , Tumeurs/génétique , Médecine de précision , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Antinéoplasiques/pharmacologie , Antinéoplasiques/usage thérapeutique , Enfant , Enfant d'âge préscolaire , Biologie informatique/méthodes , Femelle , Prédisposition génétique à une maladie , Génomique/méthodes , Humains , Nourrisson , Mâle , Adulte d'âge moyen , Thérapie moléculaire ciblée , Mutation , Tumeurs/traitement médicamenteux , Tumeurs/métabolisme , Médecine de précision/méthodes , Transduction du signal/effets des médicaments et des substances chimiques , Résultat thérapeutique , Jeune adulte
13.
Oncotarget ; 8(3): 5426-5438, 2017 Jan 17.
Article de Anglais | MEDLINE | ID: mdl-28076839

RÉSUMÉ

Morbidly obese patients who accomplish substantial weight loss often display a long-term decline in their resting metabolism, causing even relatively restrained caloric intake to trigger a relapse to the obese state. Paradoxically, we observed that morbidly obese mice receiving chemotherapy for cancer experienced spontaneous weight reduction despite unabated ingestion of their high fat diet (HFD). This response to chemotherapy could also be achieved in morbidly obese mice without cancer. Optimally dosed methotrexate (MTX) or cyclophosphamide (CY) enabled the mice to completely and safely normalize their body weight despite continued consumption of obesogenic quantities of HFD. Weight reduction was not attributable to decreased HFD intake, enhanced energy expenditure or malabsorption. MTX or CY dosing significantly depleted both adipose tissue and preadipocyte progenitors. Remarkably, however, despite continued high fat feeding, a compensatory increase in hepatocyte lipid storage was not observed, but rather the opposite. Gene microarray liver analyses demonstrated that HFD mice receiving MTX or CY experienced significantly inhibited lipogenesis and lipid storage, whereas Enho (energy homeostasis) gene expression was significantly upregulated. Further metabolic studies employing a human hepatocellular line revealed that MTX treatment preserved robust oxidative phosphorylation, but also promoted mitochondrial uncoupling with a surge in proton leak. This is the first report that certain optimally dosed chemotherapeutic agents can induce weight loss in morbidly obese mice without reduced dietary intake, apparently by depleting stores of adipocytes and their progenitors, curtailment of lipogenesis, and inconspicuous disposal of incoming dietary lipid via a steady state partial uncoupling of mitochondrial oxidative phosphorylation.


Sujet(s)
Cyclophosphamide/pharmacologie , Métabolisme énergétique/effets des médicaments et des substances chimiques , Méthotrexate/pharmacologie , Obésité morbide , Adipocytes/effets des médicaments et des substances chimiques , Animaux , Alimentation riche en graisse/effets indésirables , Mâle , Souris , Souris de lignée C57BL , Répartition aléatoire
15.
Oncolytic Virother ; 7: 13-24, 2017.
Article de Anglais | MEDLINE | ID: mdl-29616200

RÉSUMÉ

Upper gastrointestinal tract malignancies are among the most challenging cancers with regard to response to treatment and prognosis. Cancers of the esophagus, stomach, pancreas, liver, and biliary tree have dismal 5-year survival, and very modest improvements in this rate have been made in recent times. Oncolytic viruses are being developed to address these malignancies, with a focus on high safety profiles and low off-target toxicities. Each viral platform has evolved to enhance oncolytic potency and the clinical response to either single-agent viral therapy or combined viral treatment with radiotherapy and chemotherapy. A panel of genomic alterations, chimeric proteins, and pseudotyped capsids are the breakthroughs for vector success. This article revisits developments for each viral platform to each tumor type, in an attempt to achieve maximum tumor selectivity. From the bench to clinical trials, the scope of this review is to highlight the beginnings of translational oncolytic virotherapy research in upper gastrointestinal tract malignancies and provide a bioengineering perspective of the most promising platforms.

16.
JCO Precis Oncol ; 20172017.
Article de Anglais | MEDLINE | ID: mdl-30761385

RÉSUMÉ

PURPOSE: Genomic testing has increased the quantity of information available to oncologists. Unfortunately, many identified sequence alterations are variants of unknown significance (VUSs), which thus limit the clinician's ability to use these findings to inform treatment. We applied a combination of in silico prediction and molecular modeling tools and laboratory techniques to rapidly define actionable VUSs. MATERIALS AND METHODS: Exome sequencing was conducted on 308 tumors from various origins. Most single nucleotide alterations within gene coding regions were VUSs. These VUSs were filtered to identify a subset of therapeutically targetable genes that were predicted with in silico tools to be altered in function by their variant sequence. A subset of receptor tyrosine kinase VUSs was characterized by laboratory comparison of each VUS versus its wild-type counterpart in terms of expression and signaling activity. RESULTS: The study identified 4,327 point mutations of which 3,833 were VUSs. Filtering for mutations in genes that were therapeutically targetable and predicted to affect protein function reduced these to 522VUSs of interest, including a large number of kinases. Ten receptortyrosine kinase VUSs were selected to explore in the laboratory. Of these, seven were found to be functionally altered. Three VUSs (FGFR2 F276C, FGFR4 R78H, and KDR G539R) showed increased basal or ligand-stimulated ERK phosphorylation compared with their wild-type counterparts, which suggests that they support transformation. Treatment of a patient who carried FGFR2 F276C with an FGFR inhibitor resulted in significant and sustained tumor response with clinical benefit. CONCLUSION: The findings demonstrate the feasibility of rapid identification of the biologic relevance of somatic mutations, which thus advances clinicians' ability to make informed treatment decisions.

17.
Sci Rep ; 6(1): 25, 2016 12 23.
Article de Anglais | MEDLINE | ID: mdl-28003660

RÉSUMÉ

DNA focused panel sequencing has been rapidly adopted to assess therapeutic targets in advanced/refractory cancer. Integrated Genomic Profiling (IGP) utilising DNA/RNA with tumour/normal comparisons in a Clinical Laboratory Improvement Amendments (CLIA) compliant setting enables a single assay to provide: therapeutic target prioritisation, novel target discovery/application and comprehensive germline assessment. A prospective study in 35 advanced/refractory cancer patients was conducted using CLIA-compliant IGP. Feasibility was assessed by estimating time to results (TTR), prioritising/assigning putative therapeutic targets, assessing drug access, ascertaining germline alterations, and assessing patient preferences/perspectives on data use/reporting. Therapeutic targets were identified using biointelligence/pathway analyses and interpreted by a Genomic Tumour Board. Seventy-five percent of cases harboured 1-3 therapeutically targetable mutations/case (median 79 mutations of potential functional significance/case). Median time to CLIA-validated results was 116 days with CLIA-validation of targets achieved in 21/22 patients. IGP directed treatment was instituted in 13 patients utilising on/off label FDA approved drugs (n = 9), clinical trials (n = 3) and single patient IND (n = 1). Preliminary clinical efficacy was noted in five patients (two partial response, three stable disease). Although barriers to broader application exist, including the need for wider availability of therapies, IGP in a CLIA-framework is feasible and valuable in selection/prioritisation of anti-cancer therapeutic targets.


Sujet(s)
Tests diagnostiques courants/méthodes , Résistance aux substances , Génomique/méthodes , Tumeurs/diagnostic , Tumeurs/traitement médicamenteux , Humains , Études prospectives
18.
PeerJ ; 3: e970, 2015.
Article de Anglais | MEDLINE | ID: mdl-26038725

RÉSUMÉ

Objective. Bringing together genomics, transcriptomics, proteomics, and other -omics technologies is an important step towards developing highly personalized medicine. However, instrumentation has advances far beyond expectations and now we are able to generate data faster than it can be interpreted. Materials and Methods. We have developed PANDA (Pathway AND Annotation) Explorer, a visualization tool that integrates gene-level annotation in the context of biological pathways to help interpret complex data from disparate sources. PANDA is a web-based application that displays data in the context of well-studied pathways like KEGG, BioCarta, and PharmGKB. PANDA represents data/annotations as icons in the graph while maintaining the other data elements (i.e., other columns for the table of annotations). Custom pathways from underrepresented diseases can be imported when existing data sources are inadequate. PANDA also allows sharing annotations among collaborators. Results. In our first use case, we show how easy it is to view supplemental data from a manuscript in the context of a user's own data. Another use-case is provided describing how PANDA was leveraged to design a treatment strategy from the somatic variants found in the tumor of a patient with metastatic sarcomatoid renal cell carcinoma. Conclusion. PANDA facilitates the interpretation of gene-centric annotations by visually integrating this information with context of biological pathways. The application can be downloaded or used directly from our website: http://bioinformaticstools.mayo.edu/research/panda-viewer/.

19.
Br J Haematol ; 168(4): 507-10, 2015 Feb.
Article de Anglais | MEDLINE | ID: mdl-25302557

RÉSUMÉ

We constructed a multiple myeloma (MM)-specific gene panel for targeted sequencing and investigated 72 untreated high-risk (del17p) MM patients. Mutations were identified in 78% of the patients. While the majority of studied genes were mutated at similar frequency to published literature, the prevalence of TP53 mutation was increased (28%) and no mutations were found in FAM46C. This study provides a comprehensive insight into the mutational landscape of del17p high-risk MM. Additionally, our work demonstrates the practical use of a customized sequencing panel, as an easy, cheap and fast approach to characterize the mutational profile of MM.


Sujet(s)
ADN tumoral/génétique , Gènes tumoraux , Myélome multiple/génétique , Analyse de séquence d'ADN/méthodes , Aberrations des chromosomes , Chromosomes humains de la paire 17/ultrastructure , Analyse de mutations d'ADN/méthodes , Gènes p53 , Humains , Hybridation fluorescente in situ , Mutation , Risque
20.
PLoS Genet ; 10(2): e1004135, 2014 Feb.
Article de Anglais | MEDLINE | ID: mdl-24550739

RÉSUMÉ

Advanced cholangiocarcinoma continues to harbor a difficult prognosis and therapeutic options have been limited. During the course of a clinical trial of whole genomic sequencing seeking druggable targets, we examined six patients with advanced cholangiocarcinoma. Integrated genome-wide and whole transcriptome sequence analyses were performed on tumors from six patients with advanced, sporadic intrahepatic cholangiocarcinoma (SIC) to identify potential therapeutically actionable events. Among the somatic events captured in our analysis, we uncovered two novel therapeutically relevant genomic contexts that when acted upon, resulted in preliminary evidence of anti-tumor activity. Genome-wide structural analysis of sequence data revealed recurrent translocation events involving the FGFR2 locus in three of six assessed patients. These observations and supporting evidence triggered the use of FGFR inhibitors in these patients. In one example, preliminary anti-tumor activity of pazopanib (in vitro FGFR2 IC50≈350 nM) was noted in a patient with an FGFR2-TACC3 fusion. After progression on pazopanib, the same patient also had stable disease on ponatinib, a pan-FGFR inhibitor (in vitro, FGFR2 IC50≈8 nM). In an independent non-FGFR2 translocation patient, exome and transcriptome analysis revealed an allele specific somatic nonsense mutation (E384X) in ERRFI1, a direct negative regulator of EGFR activation. Rapid and robust disease regression was noted in this ERRFI1 inactivated tumor when treated with erlotinib, an EGFR kinase inhibitor. FGFR2 fusions and ERRFI mutations may represent novel targets in sporadic intrahepatic cholangiocarcinoma and trials should be characterized in larger cohorts of patients with these aberrations.


Sujet(s)
Tumeurs des canaux biliaires/traitement médicamenteux , Cholangiocarcinome/traitement médicamenteux , Récepteurs ErbB/métabolisme , Récepteur FGFR2/génétique , Transduction du signal/génétique , Tumeurs des canaux biliaires/génétique , Tumeurs des canaux biliaires/anatomopathologie , Conduits biliaires intrahépatiques/anatomopathologie , Lignée cellulaire tumorale , Cholangiocarcinome/génétique , Cholangiocarcinome/anatomopathologie , Récepteurs ErbB/antagonistes et inhibiteurs , Récepteurs ErbB/génétique , Chlorhydrate d'erlotinib , Génome humain , Humains , Imidazoles/administration et posologie , Indazoles , Thérapie moléculaire ciblée , Mutation , Pronostic , Inhibiteurs de protéines kinases , Pyridazines/administration et posologie , Pyrimidines/administration et posologie , Quinazolines/administration et posologie , Récepteur FGFR2/antagonistes et inhibiteurs , Récepteur FGFR2/métabolisme , Sulfonamides/administration et posologie , Transcriptome
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