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1.
J Insect Sci ; 24(3)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38913611

RESUMO

Tracking of soil-dwelling insects poses greater challenges compared to aboveground-dwelling animals in terrestrial systems. A metal detector system consisting of a commercially available detector and aluminum tags was developed for detecting dung beetle, Copris ochus Motschulsky (Coleoptera: Scarabaeidae). First, detection efficacy of the system was evaluated by varying volumes of aluminum tags attached on a plastic model of the insect and also by varying angles. Then, detection efficacy was evaluated by varying depths of aluminum-tagged models under soil in 2 vegetation types. Finally, the effects of tag attachment on C. ochus adults were assessed for survivorship, burrowing depth, and horizontal movement. Generally, an increase in tag volume resulted in greater detection distance in semi-field conditions. Maximum detection distance of aluminum tag increased up to 17 cm below soil surface as the tag size (0.5 × 1.0 cm [width × length]) and thickness (16 layers) were maximized, resulting in a tag weight of 31.4 mg, comprising ca. 9% of average weight of C. ochus adult. Furthermore, the detection efficacy did not vary among angles except for 90°. In the field, metal detectors successfully detected 5 aluminum-tagged models in 20 × 10 m (W × L) arena within 10 min with detection rates ≥85% for up to depth of 10 cm and 45%-60% at depth of 20 cm. Finally, aluminum tagging did not significantly affect survivorship and behaviors of C. ochus. Our study indicates the potential of metal detector system for tracking C. ochus under soil.


Assuntos
Alumínio , Besouros , Animais , Alumínio/análise , Solo/química , Entomologia/métodos , Entomologia/instrumentação , Sistemas de Identificação Animal/instrumentação
2.
BMC Vet Res ; 20(1): 233, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38807154

RESUMO

Canine mammary gland tumors (MGT) have a poor prognosis in intact female canines, posing a clinical challenge. This study aimed to establish novel canine mammary cancer cell lines from primary tumors and characterize their cellular and molecular features to find potential therapeutic drugs. The MGT cell lines demonstrated rapid cell proliferation and colony formation in an anchorage-independent manner. Vimentin and α-SMA levels were significantly elevated in MGT cell lines compared to normal canine kidney (MDCK) cells, while CDH1 expression was either significantly lower or not detected at all, based on quantitative real-time PCR (qRT-PCR) analysis. Functional annotation and enrichment analysis revealed that epithelial-mesenchymal transition (EMT) phenotypes and tumor-associated pathways, particularly the PI3K/Akt signaling pathway, were upregulated in MGT cells. BYL719 (Alpelisib), a PI3K inhibitor, was also examined for cytotoxicity on the MGT cell lines. The results show that BYL719 can significantly inhibit the proliferation of MGT cell lines in vitro. Overall, our findings suggest that the MGT cell lines may be valuable for future studies on the development, progression, metastasis, and management of tumors.


Assuntos
Doenças do Cão , Neoplasias Mamárias Animais , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Animais , Cães , Feminino , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Doenças do Cão/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/genética , Proliferação de Células/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transdução de Sinais , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia
3.
IEEE Pulse ; 15(1): 15-19, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38619929

RESUMO

The Center for Bioengineering Innovation and Design (CBID) at Johns Hopkins University (JHU) has established a comprehensive approach to addressing global health challenges. Central to CBID's modality on global health is a strategy that integrates education, research, and collaboration. Through its graduate program, CBID trains the next generation of health care innovators to address the specific needs of low- and middle-income countries (LMICs). Graduate student teams at CBID begin their year with a focus on a health care thematic area associated with a target country.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/terapia , Uganda , Atenção à Saúde , Estudantes , Engenharia Biomédica , Países em Desenvolvimento
4.
Transl Lung Cancer Res ; 13(2): 280-291, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38496698

RESUMO

Background: Limited disease (LD) small cell lung cancer (SCLC) treated with definitive concurrent chemoradiotherapy (CCRT) potentially experience disease recurrence. We investigated the feasibility of circulating-tumor DNA (ctDNA)-based genomic and fragmentome analyses to assess the risk of recurrence. Methods: Targeted sequencing was conducted using pre-treatment and on-treatment blood samples from definitive CCRT-treated patients with LD-SCLC (n=50). Based on 12-month recurrence-free survival (RFS), patients were categorized into persistent-response (PeR, n=29) and non-PeR (n=21) groups. Fragmentome analysis was conducted using ctDNA fragments of different lengths: P1 (100-155 bp) and P2 (160-180 bp). Results: Patients with TP53 (n=15) and RB1 (n=11) mutation in on-treatment samples demonstrated significantly shorter RFS than patients with wild-type (WT) (P=0.05, P=0.0014, respectively). Fragmentome analysis of all available on-treatment samples (n=26) revealed that the non-PeR group (n=10) had a significantly higher P1 range (P=0.003) and lower P2 range (P=0.002). The areas under the curves for P1, P2, and the fragmentation ratio (P1/P2) in distinguishing the PeR and non-PeR were 0.850, 0.725, and 0.900, respectively. Using optimal cut-off, longer RFSs were found with the low-fragmentation-ratio group than with the high-fragmentation-ratio group (not reached vs. 7.6 months, P=0.002). Patients with both WT RB1 and a low-fragmentation-ratio (n=10) showed better outcomes than patients with both mutated RB1 and a high-fragmentation-ratio (n=10; hazard ratio, 7.55; 95% confidence interval: 2.14-26.6; P=0.002). Conclusions: RB1 mutations and high fragmentation ratios correlated with early disease recurrence. Analyzing ctDNA could help in predicting early treatment failure and making clinical decisions for high-risk patients.

5.
Cancer Res Treat ; 56(3): 765-773, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38186238

RESUMO

PURPOSE: There have been needs to improve the sensitivity of liquid biopsy. This report aims to report the analytical and clinical validation of a next-generation sequencing (NGS)-based circulating tumor DNA (ctDNA) assay. MATERIALS AND METHODS: Analytical validation was conducted in vitro by evaluating the limit of detection (LOD), precision, and specificity for various genomic aberrations. The real-world performance in non-small cell lung cancer (NSCLC) was assessed by comparing the results of AlphaLiquid100 to the tissue-based results. RESULTS: The LODs with 30 ng input DNA were 0.11%, 0.11%, 0.06%, 0.21%, and 2.13 copies for detecting single nucleotide variants, insertions, deletions, fusions, and copy number alterations (CNA), respectively. Quantitatively, single nucleotide variants/insertions and deletions, fusions, and CNAs showed a good correlation (R2=0.91, 0.40, and 0.65; y=0.95, 1.06, and 1.19) to the manufacturer's values, and per-base specificities for all types of variants were near 100%. In real-world NSCLC (n=122), key actionable mutations in NSCLC were detected in 60.7% (74/122) with the ctDNA assay. Comparative analysis against the NGS-based tissue results for all key mutations showed positive percent agreement (PPA) of 85.3%. For individual genes, the PPA was as high as 95.7% for epidermal growth factor receptor (EGFR) mutations and 83.3% for ALK translocations. AlphaLiquid100 detected drug-sensitive EGFR mutation at a variant allele frequency as low as 0.02% and also identified an EGFR mutation in a case where tissue sample missed. Blood samples collected post-targeted therapies revealed additional acquired mutations. CONCLUSION: The AlphaLiquid100 ctDNA assay demonstrates robust analytical validity, offering clinically important information for NSCLC patients.


Assuntos
Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas , DNA Tumoral Circulante , Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/sangue , DNA Tumoral Circulante/genética , DNA Tumoral Circulante/sangue , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/sangue , Mutação , Biópsia Líquida/métodos , Variações do Número de Cópias de DNA , Masculino , Feminino , Limite de Detecção , Sensibilidade e Especificidade , Pessoa de Meia-Idade
6.
Exp Mol Med ; 55(11): 2445-2460, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37907748

RESUMO

Cell-free DNA (cfDNA) sequencing has demonstrated great potential for early cancer detection. However, most large-scale studies have focused only on either targeted methylation sites or whole-genome sequencing, limiting comprehensive analysis that integrates both epigenetic and genetic signatures. In this study, we present a platform that enables simultaneous analysis of whole-genome methylation, copy number, and fragmentomic patterns of cfDNA in a single assay. Using a total of 950 plasma (361 healthy and 589 cancer) and 240 tissue samples, we demonstrate that a multifeature cancer signature ensemble (CSE) classifier integrating all features outperforms single-feature classifiers. At 95.2% specificity, the cancer detection sensitivity with methylation, copy number, and fragmentomic models was 77.2%, 61.4%, and 60.5%, respectively, but sensitivity was significantly increased to 88.9% with the CSE classifier (p value < 0.0001). For tissue of origin, the CSE classifier enhanced the accuracy beyond the methylation classifier, from 74.3% to 76.4%. Overall, this work proves the utility of a signature ensemble integrating epigenetic and genetic information for accurate cancer detection.


Assuntos
Ácidos Nucleicos Livres , Neoplasias , Humanos , Detecção Precoce de Câncer , Variações do Número de Cópias de DNA , Neoplasias/diagnóstico , Neoplasias/genética , Metilação de DNA , Biomarcadores Tumorais/genética
7.
Br J Cancer ; 129(2): 374-381, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37280413

RESUMO

BACKGROUND: Postoperative minimal residual disease (MRD) detection using circulating-tumour DNA (ctDNA) requires a highly sensitive analysis platform. We have developed a tumour-informed, hybrid-capture ctDNA sequencing MRD assay. METHODS: Personalised target-capture panels for ctDNA detection were designed using individual variants identified in tumour whole-exome sequencing of each patient. MRD status was determined using ultra-high-depth sequencing data of plasma cell-free DNA. The MRD positivity and its association with clinical outcome were analysed in Stage II or III colorectal cancer (CRC). RESULTS: In 98 CRC patients, personalised panels for ctDNA sequencing were built from tumour data, including a median of 185 variants per patient. In silico simulation showed that increasing the number of target variants increases MRD detection sensitivity in low fractions (<0.01%). At postoperative 3-week, 21.4% of patients were positive for MRD by ctDNA. Postoperative positive MRD was strongly associated with poor disease-free survival (DFS) (adjusted hazard ratio 8.40, 95% confidence interval 3.49-20.2). Patients with a negative conversion of MRD after adjuvant therapy showed significantly better DFS (P < 0.001). CONCLUSION: Tumour-informed, hybrid-capture-based ctDNA assay monitoring a large number of patient-specific mutations is a sensitive strategy for MRD detection to predict recurrence in CRC.


Assuntos
DNA Tumoral Circulante , Neoplasias Colorretais , Humanos , DNA Tumoral Circulante/genética , Neoplasia Residual/genética , Intervalo Livre de Doença , Mutação , Biomarcadores Tumorais/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética
8.
Cancers (Basel) ; 15(10)2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37345184

RESUMO

Traditional tissue-based assessments of genomic alterations in castration-resistant prostate cancer (CRPC) can be challenging. To evaluate the real-world clinical utility of liquid biopsies for the evaluation of genomic alterations in CRPC, we preemptively collected available plasma samples and archival tissue samples from patients that were being treated for clinically confirmed CRPC. The cell-free DNA (cfDNA) and tumor tissue DNA were analyzed using the AlphaLiquid®100-HRR panel. Plasma samples from a total of 87 patients were included in this study. Somatic mutations from cfDNA were detected in 78 (89.7%) patients, regardless of the presence of overt metastasis or concomitant treatment given at the time of plasma sample collection. Twenty-three patients were found to have known deleterious somatic or germline mutations in HRR genes from their cfDNA. Archival tissue samples from 33 (37.9%) patients were available for comparative analysis. Tissue sequencing was able to yield an NGS result in only 51.5% of the tissue samples. The general sensitivity of cfDNA for detecting somatic mutations in tissues was 71.8%, but important somatic/germline mutations in HRR genes were found to have a higher concordance (100%). Liquid biopsies can be a reasonable substitute for tissue biopsies in CRPC patients when evaluating genomic alterations.

9.
Cancers (Basel) ; 15(10)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37345205

RESUMO

Patients with hematuria are commonly given an invasive cystoscopy test to detect bladder cancer (BC). To avoid the risks associated with cystoscopy, several urine-based methods for BC detection have been developed, the most prominent of which is the deep sequencing of urine DNA. However, the current methods for urine-based BC detection have significant levels of false-positive signals. In this study, we report on uAL100, a method to precisely detect BC tumor DNA in the urine without tumor samples. Using urine samples from 43 patients with BC and 21 healthy donors, uAL100 detected BC with 83.7% sensitivity and 100% specificity. The mutations identified in the urine DNA by uAL100 for BC detection were highly associated with BC tumorigenesis and progression. We suggest that uAL100 has improved accuracy compared to other urine-based methods for early BC detection and can reduce unnecessary cystoscopy tests for patients with hematuria.

10.
Int J Cancer ; 153(3): 571-583, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37194418

RESUMO

Emerging new mutations after treatment can provide clues to acquired resistant mechanisms. Circulating tumor DNA (ctDNA) sequencing has enabled noninvasive repeated tumor mutational profiling. We aimed to investigate newly emerging mutations in ctDNA after disease progression in metastatic colorectal cancer (mCRC). Blood samples were prospectively collected from mCRC patients receiving palliative chemotherapy before treatment and at radiological evaluations. ctDNA from pretreatment and progressive disease (PD) samples were sequenced with a next-generation sequencing panel targeting 106 genes. A total of 712 samples from 326 patients were analyzed, and 381 pretreatment and PD pairs (163 first-line, 85 second-line and 133 later-line [≥third-line]) were compared. New mutations in PD samples (mean 2.75 mutations/sample) were observed in 49.6% (189/381) of treatments. ctDNA samples from later-line had more baseline mutations (P = .002) and were more likely to have new PD mutations (adjusted odds ratio [OR] 2.27, 95% confidence interval [CI]: 1.40-3.69) compared to first-line. RAS/BRAF wild-type tumors were more likely to develop PD mutations (adjusted OR 1.87, 95% CI: 1.22-2.87), independent of cetuximab treatment. The majority of new PD mutations (68.5%) were minor clones, suggesting an increasing clonal heterogeneity after treatment. Pathways involved by PD mutations differed by the treatment received: MAPK cascade (Gene Ontology [GO]: 0000165) in cetuximab and regulation of kinase activity (GO: 0043549) in regorafenib. The number of mutations revealed by ctDNA sequencing increased during disease progression in mCRC. Clonal heterogeneity increased after chemotherapy progression, and pathways involved were affected by chemotherapy regimens.


Assuntos
DNA Tumoral Circulante , Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , DNA Tumoral Circulante/genética , Cetuximab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Progressão da Doença , Mutação , Biomarcadores Tumorais/genética , Análise Mutacional de DNA
11.
J Korean Med Sci ; 38(19): e146, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37191849

RESUMO

BACKGROUND: While the importance of mental health is well-recognized in the field of occupational health, implementation of effective strategies in the workplace has been limited by gaps in infrastructure, program comprehensiveness, coverage, and adherence. The authors developed a Screening, Brief Intervention, and Referral to Treatment (SBIRT) model based occupational mental health intervention, and implemented in a web-based format with a smartphone application. METHODS: The SBIRT-based intervention was developed by a multidisciplinary team, including occupational health physicians, nurses, psychiatrists, and software developers. The following mental health areas were included, based on outcomes of an epidemiological survey conducted: insomnia, depression, anxiety, problematic alcohol use, and suicidal risk. The viability of the two-step evaluation process utilizing a combination of the brief version and the full-length version of the questionnaire was examined using responses from the survey. The intervention was adjusted according to the survey results and expert opinions. RESULTS: The epidemiological survey included 346 employees who completed the long-form version of mental health scales. These data were the used to confirm the diagnostic value of using a combination of short-form and long-form version of the scales for screening in the SBIRT model. The model uses a smartphone application for screening, provision of psychoeducation, and for surveillance. The universal methods of the model ensure it can be implemented by all occupational managers, regardless of their specialization in mental health. In addition to the two-step screening procedure to identify employees at-risk for mental health problems, the model includes a stepped care approach, based on risk stratification, to promote mental health education, management, and follow-up for continuous care. CONCLUSION: The SBIRT model-based intervention provides an easy-to-implement approach for the management of mental health in the workplace. Further studies are required to examine the effectiveness and feasibility of the model.


Assuntos
Saúde Ocupacional , Transtornos Relacionados ao Uso de Substâncias , Humanos , Intervenção em Crise , Smartphone , Saúde Mental , Encaminhamento e Consulta , Inquéritos e Questionários , Internet , Programas de Rastreamento/métodos , Transtornos Relacionados ao Uso de Substâncias/diagnóstico
12.
Cancer Res Treat ; 55(3): 927-938, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36915247

RESUMO

PURPOSE: Circulating tumor DNA (ctDNA) is emerging as a valuable non-invasive tool to identify tumor heterogeneity and tumor burden. This study investigated ctDNA dynamics in metastatic colorectal cancer patients treated with regorafenib. Materials and Methods: In this prospective biomarker study, plasma cell-free DNA (cfDNA) samples obtained at baseline, at the first response evaluation after 2 cycles of treatment, and at the time of progressive disease were sequenced using a targeted next-generation sequencing platform which included 106 genes. RESULTS: A total of 285 blood samples from 110 patients were analyzed. Higher baseline cfDNA concentration was associated with worse progression-free survival (PFS) and overall survival (OS). After 2 cycles of treatment, variant allele frequency (VAF) in the majority of ctDNA mutations decreased with a mean relative change of -31.6%. Decreases in the VAF of TP53, APC, TCF7L2, and ROS1 after 2 cycles of regorafenib were associated with longer PFS. We used the sum of VAF at each time point as a surrogate for the overall ctDNA burden. A reduction in sum (VAF) of ≥ 50% after 2 cycles was associated with longer PFS (6.1 vs. 2.7 months, p=0.002), OS (11.3 vs. 5.9 months, p=0.001), and higher disease control rate (86.3% vs. 51.1%, p < 0.001). VAF of the majority of the ctDNA mutations increased at the time of disease progression, and VAF of BRAF increased markedly. CONCLUSION: Reduction in ctDNA burden as estimated by sum (VAF) could be used to predict treatment outcome of regorafenib.


Assuntos
Ácidos Nucleicos Livres , DNA Tumoral Circulante , Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , DNA Tumoral Circulante/genética , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Resultado do Tratamento , Neoplasias do Colo/patologia , Biomarcadores Tumorais/genética , Mutação , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética
13.
Clin Epigenetics ; 15(1): 34, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36859282

RESUMO

BACKGROUND: A growing body of research has emphasized 5-hydroxymethylcytosine (5hmC) as an important epigenetic mark. High-resolution methods to detect 5hmC require high sequencing depth and are therefore expensive. Many studies have used enrichment-based methods to detect 5hmC; however, conventional enrichment-based methods have limited resolution. To overcome these limitations, we developed EBS-seq, a cost-efficient method for 5hmC detection with single-base resolution that combines the advantages of high-resolution methods and enrichment-based methods. RESULTS: EBS-seq uses selective labeling of 5hmC, deamination of cytosine and 5-methylcytosine, pull-down of labeled 5hmC, and C-to-T conversion during DNA amplification. Using this method, we profiled 5hmC in HEK293T cells and two colorectal cancer samples. Compared with conventional enrichment-based 5hmC detection, EBS-seq improved 5hmC signals by localizing them at single-base resolution. Furthermore, EBS-seq was able to determine 5hmC levels in CpG-dense regions where distortion of signals can occur, such as CpG islands and CpG shores. Comparing EBS-seq and conventional high-resolution 5hmC detection by ACE-seq, we showed that EBS-seq is more effective at finding 5hmC sites. Using EBS-seq, we found strong associations between gene expression and gene-body 5hmC content in both HEK293T cells and colorectal cancer samples. CONCLUSIONS: EBS-seq is a reliable and cost-efficient method for 5hmC detection because it simultaneously enriches 5hmC-containing DNA fragments and localizes 5hmC signals at single-base resolution. This method is a promising choice for 5hmC detection in challenging clinical samples with low 5hmC levels, such as cancer tissues.


Assuntos
5-Metilcitosina , Neoplasias Colorretais , Humanos , Células HEK293 , Metilação de DNA
14.
Cancer Res Treat ; 55(3): 1048-1052, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36731462

RESUMO

Poly(ADP-ribose) polymerase inhibitors have been shown dramatic responses in patients with BRCAness. However, clinical studies have been limited to breast cancer patients with germline mutations. Here, we describe a patient with metastatic breast cancer who had a rare BRCA1 somatic mutation (BRCA1 c.4336G>T (p.E1446*)) detected by cell-free DNA analysis after failing standard therapies. This tier III variant of unknown significance was predicted to be a pathogenic variant in our assessment, leading us to consider off-label treatment with olaparib. The patient responded well to olaparib for several months, with a decrease in allele frequency of this BRCA1 somatic mutation in cell-free DNA. Olaparib resistance subsequently developed with an increase in the allele frequency and new BRCA1 reversion mutations. To our knowledge, this is the first report confirming BRCA1 c.4336G>T (p.E1446*) as a mutation sensitive to olaparib in breast cancer and describing the dynamic changes in the associated mutations using liquid biopsy.


Assuntos
Neoplasias da Mama , Ácidos Nucleicos Livres , DNA Tumoral Circulante , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , DNA Tumoral Circulante/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Mutação , Ácidos Nucleicos Livres/uso terapêutico
15.
Bioact Mater ; 22: 112-126, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36203958

RESUMO

Inspired by erythrocytes that contain oxygen-carrying hemoglobin (Hb) and that exhibit photo-driven activity, we introduce homogenous-sized erythrocyte-like Hb microgel (µGel) systems (5-6 µm) that can (i) emit heat, (ii) supply oxygen, and (iii) generate reactive oxygen species (ROS; 1O2) in response to near-infrared (NIR) laser irradiation. Hb µGels consist of Hb, bovine serum albumin (BSA), chlorin e6 (Ce6) and erbium@lutetium upconverting nanoparticles (UCNPs; ∼35 nm) that effectively convert 808 nm NIR light to 660 nm visible light. These Hb µGels are capable of releasing oxygen to help generate sufficient reactive oxygen species (1O2) from UCNPs/Ce6 under severely hypoxic condition upon NIR stimulation for efficient photodynamic activity. Moreover, the Hb µGels emit heat and increase surface temperature due to NIR light absorption by heme (iron protoporphyrin IX) and display photothermal activity. By changing the Hb/UCNP/Ce6 ratio and controlling the amount of NIR laser irradiation, it is possible to formulate bespoke Hb µGels with either photothermal or photodynamic activity or both in the context of combined therapeutic effect. These Hb µGels effectively suppress highly hypoxic 4T1 cell spheroid growth and xenograft mice tumors in vivo.

16.
Br J Cancer ; 127(5): 898-907, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35643791

RESUMO

BACKGROUND: Circulating tumour DNA (ctDNA) has been spotlighted as an attractive biomarker because of its easy accessibility and real-time representation of tumour genetic profile. However, the clinical utility of longitudinal ctDNA monitoring has not been clearly defined. METHODS: Serial blood samples were obtained from metastatic colorectal cancer patients undergoing first-line chemotherapy. ctDNA was sequenced using a targeted next-generation sequencing platform which included 106 genes. Changes in ctDNA profile and treatment outcome were comprehensively analysed. RESULTS: A total of 272 samples from 62 patients were analysed. In all, 90.3% of patients had detectable ctDNA mutation before treatment. ctDNA clearance after chemotherapy was associated with longer progression-free survival which was independent of radiological response (adjusted hazard ratio 0.22, 95% confidence interval 0.10-0.46). Longitudinal monitoring was able to detect ctDNA progression which preceded radiological progressive disease (PD) in 58.1% (median 3.3 months). Diverse resistant mutations (34.9%) and gene amplification (7.0%) at the time of PD were discovered. For 16.3% of the PD patients, the newly identified mutations could be potential candidates of targeted therapy or clinical trial. CONCLUSION: ctDNA profile provided a more accurate landscape of tumour and dynamic changes compared to radiological evaluation. Longitudinal ctDNA monitoring may improve personalised treatment decision-making.


Assuntos
DNA Tumoral Circulante , Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Biomarcadores Tumorais/genética , DNA Tumoral Circulante/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , DNA de Neoplasias/genética , Humanos , Mutação
17.
Oncogene ; 41(14): 2026-2038, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35173310

RESUMO

The emergence of RAS/RAF mutant clone is the main feature of EGFR inhibitor resistance in KRAS wild-type colon cancer. However, its molecular mechanism is thought to be multifactorial, mainly due to cellular heterogeneity. In order to better understand the resistance mechanism in a single clone level, we successfully isolated nine cells with cetuximab-resistant (CR) clonality from in vitro system. All CR cells harbored either KRAS or BRAF mutations. Characteristically, these cells showed a higher EMT (Epithelial to mesenchymal transition) signature, showing increased EMT markers such as SNAI2. Moreover, the expression level of CXCL1/5, a secreted protein, was significantly higher in CR cells compared to the parental cells. In these CR cells, CXCL1/5 expression was coordinately regulated by SNAI2/NFKB and transactivated EGFR through CXCR/MMPI/EGF axis via autocrine singling. We also observed that combined cetuximab/MEK inhibitor not only showed growth inhibition but also reduced the secreted amounts of CXCL1/5. We further found that serum CXCL1/5 level was positively correlated with the presence of RAS/RAF mutation in colon cancer patients during cetuximab therapy, suggesting its role as a biomarker. These data indicated that the application of serum CXCL1/5 could be a potential serologic biomarker for predicting resistance to EGFR therapy in colorectal cancer.


Assuntos
Neoplasias Colorretais , Transição Epitelial-Mesenquimal , Cetuximab/uso terapêutico , Quimiocina CXCL1/genética , Quimiocina CXCL1/metabolismo , Quimiocina CXCL5/genética , Quimiocina CXCL5/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Humanos , Mutação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética
18.
Mol Oncol ; 16(12): 2396-2412, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34850547

RESUMO

Patient-derived organoids are being considered as models that can help guide personalized therapy through in vitro anticancer drug response evaluation. However, attempts to quantify in vitro drug responses in organoids and compare them with responses in matched patients remain inadequate. In this study, we investigated whether drug responses of organoids correlate with clinical responses of matched patients and disease progression of patients. Organoids were established from 54 patients with colorectal cancer who (except for one patient) did not receive any form of therapy before, and tumor organoids were assessed through whole-exome sequencing. For comparisons of in vitro drug responses in matched patients, we developed an 'organoid score' based on the variable anticancer treatment responses observed in organoids. Very interestingly, a higher organoid score was significantly correlated with a lower tumor regression rate after the standard-of-care treatment in matched patients. Additionally, we confirmed that patients with a higher organoid score (≥ 2.5) had poorer progression-free survival compared with those with a lower organoid score (< 2.5). Furthermore, to assess potential drug repurposing using an FDA-approved drug library, ten tumor organoids derived from patients with disease progression were applied to a simulation platform. Taken together, organoids and organoid scores can facilitate the prediction of anticancer therapy efficacy, and they can be used as a simulation model to determine the next therapeutic options through drug screening. Organoids will be an attractive platform to enable the implementation of personalized therapy for colorectal cancer patients.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Progressão da Doença , Humanos , Organoides , Medicina de Precisão
19.
Sci Rep ; 11(1): 16333, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381078

RESUMO

Circulating tumor DNA (ctDNA) may reveal dynamic tumor status during therapy. We conducted serial ctDNA analysis to investigate potential association with clinical outcome in metastatic colorectal cancer (mCRC) patients receiving chemotherapy. Tissue KRAS/NRAS wild-type mCRC patients were enrolled and treated with first-line cetuximab-containing chemotherapy. ctDNA isolated from plasma were analyzed by next generation sequencing (NGS) with 16 targeted gene panel. Among 93 patients, 84 (90.3%) had at least 1 somatic mutation in baseline ctDNA samples (average 2.74). Five patients with KRAS or NRAS hotspot mutation in the ctDNA showed significantly worse progression-free survival (PFS) (p = 0.029). Changes in average variant allele frequency (VAF) in ctDNA showed significant correlation with tumor size change at the time of first response evaluation (p = 0.020) and progressive disease (PD) (p = 0.042). Patients whose average VAF decreased below cutoff (< 1%) at the first evaluation showed significantly better PFS (p < 0.001), and the average VAF change further discriminated the PFS in the patients in partial response (p = 0.018). At the time of PD, 54 new mutations including KRAS and MAP2K1 emerged in ctDNA. ctDNA sequencing can provide mutation profile that could better reflect tumor mutation status and predict treatment outcome.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , DNA Tumoral Circulante/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/uso terapêutico , Cetuximab/uso terapêutico , DNA Tumoral Circulante/sangue , Neoplasias Colorretais/sangue , Receptores ErbB/metabolismo , Feminino , Frequência do Gene/efeitos dos fármacos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/efeitos dos fármacos , Intervalo Livre de Progressão , Proteínas ras/genética
20.
PLoS One ; 16(2): e0246356, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33524032

RESUMO

In the present study, we developed a computational method and panel markers to assess microsatellite instability (MSI) using a targeted next-generation sequencing (NGS) platform and compared the performance of our computational method, mSILICO, with that of mSINGS to detect MSI in CRCs. We evaluated 13 CRC cell lines, 84 fresh and 119 formalin-fixed CRC tissues (including 61 MSI-high CRCs and 155 microsatellite-stable CRCs) and tested the classification performance of the two methods on 23, 230, and 3,154 microsatellite markers. For the fresh tissue and cell line samples, mSILICO showed a sensitivity of 100% and a specificity of 100%, regardless of the number of panel markers, whereas for the formalin-fixed tissue samples, mSILICO exhibited a sensitivity of up to 100% and a specificity of up to 100% with three differently sized panels ranging from 23 to 3154. These results were similar to those of mSINGS. With the application of mSILICO, the small panel of 23 markers had a sensitivity of ≥95% and a specificity of 100% in cell lines/fresh tissues and formalin-fixed tissues of CRC. In conclusion, we developed a new computational method and microsatellite marker panels for the determination of MSI that does not require paired normal tissues. A small panel could be integrated into the targeted NGS panel for the concurrent analysis of single nucleotide variations and MSI.


Assuntos
Neoplasias Colorretais/genética , Instabilidade de Microssatélites , Linhagem Celular Tumoral , Predisposição Genética para Doença/genética , Testes Genéticos/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Repetições de Microssatélites/genética , Sensibilidade e Especificidade
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