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1.
Vet Sci ; 8(12)2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34941828

RESUMO

First-line treatments of cancer do not always work, and even when they do, they cure the disease at unequal rates mostly owing to biological and clinical heterogeneity across patients. Accurate prediction of clinical outcome and survival following the treatment can support and expedite the process of comparing alternative treatments. We describe the methodology to dynamically determine remission probabilities for individual patients, as well as their prospects of progression-free survival (PFS). The proposed methodology utilizes the ex vivo drug sensitivity of cancer cells, their immunophenotyping results, and patient information, such as age and breed, in training machine learning (ML) models, as well as the Cox hazards model to predict the probability of clinical remission (CR) or relapse across time for a given patient. We applied the methodology using the three types of data obtained from 242 canine lymphoma patients treated by (L)-CHOP chemotherapy. The results demonstrate substantial enhancement in the predictive accuracy of the ML models by utilizing features from all the three types of data. They also highlight superior performance and utility in predicting survival compared to the conventional stratification method. We believe that the proposed methodology can contribute to improving and personalizing the care of cancer patients.

2.
Vet Comp Oncol ; 19(1): 160-171, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33025640

RESUMO

We report a precision medicine platform that evaluates the probability of chemotherapy drug efficacy for canine lymphoma by combining ex vivo chemosensitivity and immunophenotyping assays with computational modelling. We isolated live cancer cells from fresh fine needle aspirates of affected lymph nodes and collected post-treatment clinical responses in 261 canine lymphoma patients scheduled to receive at least 1 of 5 common chemotherapy agents (doxorubicin, vincristine, cyclophosphamide, lomustine and rabacfosadine). We used flow cytometry analysis for immunophenotyping and ex vivo chemosensitivity testing. For each drug, 70% of treated patients were randomly selected to train a random forest model to predict the probability of positive Veterinary Cooperative Oncology Group (VCOG) clinical response based on input variables including antigen expression profiles and treatment sensitivity readouts for each patient's cancer cells. The remaining 30% of patients were used to test model performance. Most models showed a test set ROC-AUC > 0.65, and all models had overall ROC-AUC > 0.95. Predicted response scores significantly distinguished (P < .001) positive responses from negative responses in B-cell and T-cell disease and newly diagnosed and relapsed patients. Patient groups with predicted response scores >50% showed a statistically significant reduction (log-rank P < .05) in time to complete response when compared to the groups with scores <50%. The computational models developed in this study enabled the conversion of ex vivo cell-based chemosensitivity assay results into a predicted probability of in vivo therapeutic efficacy, which may help improve treatment outcomes of individual canine lymphoma patients by providing predictive estimates of positive treatment response.


Assuntos
Antineoplásicos/uso terapêutico , Doenças do Cão/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Imunofenotipagem/veterinária , Linfoma/veterinária , Animais , Doenças do Cão/patologia , Cães , Feminino , Linfonodos/patologia , Linfoma/tratamento farmacológico , Linfoma/patologia , Aprendizado de Máquina , Masculino , Modelos Biológicos , Valor Preditivo dos Testes
3.
Nat Microbiol ; 4(3): 429-437, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30617349

RESUMO

Severe fever with thrombocytopenia syndrome phlebovirus (SFTSV), listed in the World Health Organization Prioritized Pathogens, is an emerging phlebovirus with a high fatality1-4. Owing to the lack of therapies and vaccines5,6, there is a pressing need to understand SFTSV pathogenesis. SFSTV non-structural protein (NSs) has been shown to block type I interferon induction7-11 and facilitate disease progression12,13. Here, we report that SFTSV-NSs targets the tumour progression locus 2 (TPL2)-A20-binding inhibitor of NF-κB activation 2 (ABIN2)-p105 complex to induce the expression of interleukin-10 (IL-10) for viral pathogenesis. Using a combination of reverse genetics, a TPL2 kinase inhibitor and Tpl2-/- mice showed that NSs interacted with ABIN2 and promoted TPL2 complex formation and signalling activity, resulting in the marked upregulation of Il10 expression. Whereas SFTSV infection of wild-type mice led to rapid weight loss and death, Tpl2-/- mice or Il10-/- mice survived an infection. Furthermore, SFTSV-NSs P102A and SFTSV-NSs K211R that lost the ability to induce TPL2 signalling and IL-10 production showed drastically reduced pathogenesis. Remarkably, the exogenous administration of recombinant IL-10 effectively rescued the attenuated pathogenic activity of SFTSV-NSs P102A, resulting in a lethal infection. Our study demonstrates that SFTSV-NSs targets the TPL2 signalling pathway to induce immune-suppressive IL-10 cytokine production as a means to dampen the host defence and promote viral pathogenesis.


Assuntos
Interações Hospedeiro-Patógeno , MAP Quinase Quinase Quinases/metabolismo , Phlebovirus/patogenicidade , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais , Proteínas não Estruturais Virais/genética , Proteínas Adaptadoras de Transdução de Sinal , Animais , Infecções por Bunyaviridae/imunologia , Infecções por Bunyaviridae/patologia , Feminino , Células HEK293 , Células HeLa , Humanos , Interleucina-10/administração & dosagem , Interleucina-10/genética , MAP Quinase Quinase Quinases/imunologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Phlebovirus/efeitos dos fármacos , Proteínas Proto-Oncogênicas/imunologia , Células RAW 264.7 , Genética Reversa
4.
J Biotechnol ; 260: 91-97, 2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-28935568

RESUMO

Oncolytic virotherapy is a promising novel approach that overcomes the limitations posed by radiation and chemotherapy. In this study, the oncolytic efficacy of a recombinant Newcastle disease virus (rNDV) BC-KLQL-GFP, against prostate cancer stem-like/tumor initiating cells was evaluated. Xenograft derived prostaspheres (XPS) induced tumor more efficiently than monolayer cell derived prostaspheres (MCPS) in nude mice. Primary and secondary XPS show enhanced self-renewal and clonogenic potential compared to MCPS. XPS also expressed embryonic stem cell markers, such as Nanog, CD44 and Nestin. Further, prostate specific antigen (PSA) activated recombinant Newcastle Disease Virus (rNDV) was selectively cytotoxic to tumor derived DU145 prostaspheres. An effective concentration (EC50) of 0.11-0.14 multiplicity of infection was sufficient to cause prostasphere cell death in serum free culture. DU145 tumor xenograft derived prostaspheres were used as tumor surrogates as they were enriched for a putative tumor initiating cell population. PSA activated rNDV was efficient in inducing cell death of cells and prostaspheres derived from primary xenografts ex-vivo, thus signifying a potential in vivo efficacy. The EC50 (∼0.1 MOI) for cytolysis of tumor initiating cells was slightly higher than that was required for the parental cell line, but within the therapeutic margin for safety and efficacy.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Engenharia Genética/métodos , Vírus da Doença de Newcastle/genética , Terapia Viral Oncolítica/métodos , Neoplasias da Próstata/metabolismo , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Feminino , Masculino , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Vet World ; 10(3): 348-352, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28435199

RESUMO

AIM: Sequence analysis and phylogenetic studies based on non-structural protein-3 (NS3) gene are important in understanding the evolution and epidemiology of bluetongue virus (BTV). This study was aimed at characterizing the NS3 gene sequence of Indian BTV serotype-2 (BTV2) to elucidate its genetic relationship to global BTV isolates. MATERIALS AND METHODS: The NS3 gene of BTV2 was amplified from infected BHK-21 cell cultures, cloned and subjected to sequence analysis. The generated NS3 gene sequence was compared with the corresponding sequences of different BTV serotypes across the world, and a phylogenetic relationship was established. RESULTS: The NS3 gene of BTV2 showed moderate levels of variability in comparison to different BTV serotypes, with nucleotide sequence identities ranging from 81% to 98%. The region showed high sequence homology of 93-99% at amino acid level with various BTV serotypes. The PPXY/PTAP late domain motifs, glycosylation sites, hydrophobic domains, and the amino acid residues critical for virus-host interactions were conserved in NS3 protein. Phylogenetic analysis revealed that BTV isolates segregate into four topotypes and that the Indian BTV2 in subclade IA is closely related to Asian and Australian origin strains. CONCLUSION: Analysis of the NS3 gene indicated that Indian BTV2 isolate is closely related to strains from Asia and Australia, suggesting a common origin of infection. Although the pattern of evolution of BTV2 isolate is different from other global isolates, the deduced amino acid sequence of NS3 protein demonstrated high molecular stability.

6.
Vet Microbiol ; 201: 208-215, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28284612

RESUMO

Genetic lineages of swine influenza A viruses (SIVs) have recently been established in Turkeys in the United States. To identify molecular determinants that are involved in virulence and transmission of SIVs to Turkeys, we sequentially passaged two triple reassortant H3N2 SIV isolates from Minnesota in ten day old specific-pathogen free (SPF) Turkey embryos and tested them in seven-day old Turkey poults. We found that SIV replication in Turkey embryos led to minimal mutations in and around the receptor binding and antigenic sites of the HA molecule, while other gene segments were unchanged. The predominant changes associated with Turkey embryo passage were A223V, V226A and T248I mutations in the receptor-binding and glycosylation sites of the HA molecule. Furthermore, Turkey embryo propagation altered receptor specificity in SIV strain 07-1145. Embryo passaged 07-1145 virus showed a decrease in α2, 6 sialic acid receptor binding compared to the wild type virus. Intranasal infection of wild type SIVs in one-week-old Turkey poults resulted in persistent diarrhea and all the infected birds seroconverted at ten days post infection. The 07-1145 wild type virus also transmitted to age matched in-contact birds introduced one-day post infection. Turkeys infected with embryo passaged viruses displayed no clinical signs and were not transmitted to in-contact poults. Our results suggest that Turkey embryo propagation attenuates recent TR SIVs for infectivity and transmission in one week old Turkeys. Our findings will have important implications in identifying molecular determinants that control the transmission and virulence of TR SIVs in Turkeys and other species.


Assuntos
Vírus da Influenza A Subtipo H3N2/patogenicidade , Infecções por Orthomyxoviridae/veterinária , Vírus Reordenados/patogenicidade , Doenças dos Suínos/virologia , Animais , Diarreia/veterinária , Diarreia/virologia , Feminino , Vírus da Influenza A Subtipo H3N2/fisiologia , Minnesota , Modelos Moleculares , Infecções por Orthomyxoviridae/transmissão , Infecções por Orthomyxoviridae/virologia , Óvulo/virologia , Vírus Reordenados/fisiologia , Organismos Livres de Patógenos Específicos , Suínos , Doenças dos Suínos/transmissão , Perus , Virulência
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