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1.
Semin Immunol ; 56: 101580, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34920941

RESUMO

Polyvalent interactions mediate the formation of higher-order macromolecular assemblies to improve the sensitivity, specificity, and temporal response of biological signals. In host defense, innate immune pathways recognize danger signals to alert host of insult or foreign invasion, while limiting aberrant activation from auto-immunity and cellular senescence. Of recent attention are the unique higher-order assemblies in the cGAS-STING pathway. Natural stimulation of cGAS enzymes by dsDNA induces phase separation and enzymatic activation for switchlike production of cGAMP. Subsequent binding of cGAMP to STING induces oligomerization of STING molecules, offering a scaffold for kinase assembly and signaling transduction. Additionally, the discovery of PC7A, a synthetic polymer which activates STING through a non-canonical biomolecular condensation, illustrates the engineering design of agonists by polyvalency principles. Herein, we discuss a mechanistic and functional comparison of natural and synthetic agonists to advance our understanding in STING signaling and highlight the principles of polyvalency in innate immune activation. The combination of exogenous cGAMP along with synthetic PC7A stimulation of STING offers a synergistic strategy in spatiotemporal orchestration of the immune milieu for a safe and effective immunotherapy against cancer.


Assuntos
Imunidade Inata , Proteínas de Membrana , Humanos , Imunoterapia , Proteínas de Membrana/agonistas , Proteínas de Membrana/metabolismo , Nucleotidiltransferases/metabolismo , Transdução de Sinais
2.
Cancer ; 128(1): 112-121, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34499355

RESUMO

BACKGROUND: Tobacco dependence, alcohol abuse, depression, distress, and other adverse patient-level influences are common in head and neck cancer (HNC) survivors. Their interrelatedness and precise burden in comparison with survivors of other cancers are poorly understood. METHODS: National Health Interview Survey data from 1997 to 2016 were pooled. The prevalence of adverse patient-level influences among HNC survivors and matched survivors of other cancers were compared using descriptive statistics. Multivariable logistic regressions evaluating covariate associations with the primary study outcomes were performed. These included 1) current cigarette smoking and/or heavy alcohol use (>14 drinks per week) and 2) high mental health burden (severe psychological distress [Kessler Index ≥ 13] and/or frequent depressive/anxiety symptoms). RESULTS: In all, 918 HNC survivors and 3672 matched survivors of other cancers were identified. Compared with other cancer survivors, more HNC survivors were current smokers and/or heavy drinkers (24.6% [95% CI, 21.5%-27.7%] vs 18.0% [95% CI, 16.6%-19.4%]) and exhibited a high mental health burden (18.6% [95% CI, 15.7%-21.5%] vs 13.0% [95% CI, 11.7%-14.3%]). In multivariable analyses, 1) a high mental health burden predicted for smoking and/or heavy drinking (odds ratio [OR], 1.4; 95% CI, 1.0-1.9), and 2) current cigarette smoking predicted for a high mental health burden (OR, 1.7; 95% CI, 1.2-2.3). Furthermore, nonpartnered marital status and uninsured/Medicaid insurance status were significantly associated with both cigarette smoking and/or heavy alcohol use (ORs, 1.9 [95% CI, 1.4-2.5] and 1.5 [95% CI, 1.0-2.1], respectively) and a high mental health burden (ORs, 1.4 [95% CI, 1.1 -1.8] and 3.0 [95% CI, 2.2-4.2], respectively). CONCLUSIONS: Stakeholders should allocate greater supportive care resources to HNC survivors. The interdependence of substance abuse, adverse mental health symptoms, and other adverse patient-level influences requires development of novel, multimodal survivorship care interventions.


Assuntos
Sobreviventes de Câncer , Neoplasias de Cabeça e Pescoço , Transtornos Relacionados ao Uso de Substâncias , Sobreviventes de Câncer/psicologia , Neoplasias de Cabeça e Pescoço/epidemiologia , Humanos , Saúde Mental , Inquéritos e Questionários
3.
Support Care Cancer ; 30(9): 7517-7525, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35666302

RESUMO

PURPOSE: Acute and chronic pain during and after radiotherapy is an important driver of poor quality of life. We aimed to identify risk factors associated with increased chronic opioid use in head and neck squamous cell cancer survivors. METHODS: We performed a retrospective cohort analysis on head and neck squamous cell cancer patients treated with definitive or adjuvant intensity-modulated radiotherapy. We tracked their oncologic opioid prescription profile from initial presentation to the last follow-up date. We determined the incidences of 1- and 2-year opioid use and performed multivariate logistic regression for both outcomes. RESULTS: Our analytic cohort consisted of 403 head and neck squamous cell cancer survivors. The numbers of patients requiring opioids at 3 months, 6 months, and 1 year after treatment were 316 (78%), 203 (50%), and 102 (25%), respectively. On multivariate logistic regression, positive smoking history (95% CI 1.86 [1.03, 3.43], p = 0.04), unemployment (95% CI 2.33 [1.16, 4.67], p = 0.02), prior psychiatric illness (95% CI 2.15 [1.05, 4.40], p = 0.03), and opiate use before radiotherapy (95% CI 2.75 [1.49, 5.20], p = 0.01) were independently associated with significantly greater odds of opioid use at 1 year. CONCLUSIONS: Our institutional analysis has shown that a substantial amount of head and neck cancer survivors are chronically dependent on opioids following radiotherapy. We have identified a cohort at highest risk for long-term use, for whom early interventions should be targeted.


Assuntos
Neoplasias de Cabeça e Pescoço , Transtornos Relacionados ao Uso de Opioides , Radioterapia de Intensidade Modulada , Analgésicos Opioides/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Transtornos Relacionados ao Uso de Opioides/etiologia , Qualidade de Vida , Radioterapia de Intensidade Modulada/efeitos adversos , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico
4.
Am J Otolaryngol ; 43(5): 103555, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36037765

RESUMO

PURPOSE: To characterize the significance of patient-level influences, including smoking history, on oncologic outcomes in human papillomavirus (HPV)-mediated oropharyngeal cancer (OPC). MATERIALS AND METHODS: A bi-institutional retrospective cohort study of previously untreated, HPV+ OPC patients who underwent curative treatment from 1/1/2008 to 7/1/2018 was performed. The primary outcome was disease-free survival (DFS) and the primary exposure was ≤10 versus >10-pack-year (PY)-smoking history. RESULTS: Among 953 OPC patients identified, 342 individuals with HPV+ OPC were included. The median patient age was 62 years, 33.0% had a > 10-PY-smoking history, 60.2% had AJCC8 stage I disease, and 35.0% underwent primary surgery. The median follow-up was 49 months (interquartile range [IQR] 32-75 months). Four-year DFS-estimates were similar among patients with ≤10-PY-smoking history (78.0%, 95% CI:71.7%-83.1%) compared to >10-PYs (74.8%; 95% CI:65.2%-82.0%; log-rank:p = 0.53). On univariate analysis, >10-PY-smoking history did not correlate with DFS (hazard ratio[HR]:1.15;95% CI:0.74-1.79) and remained nonsignificant when forced into the multivariable model. On adjusted analyses, stage, treatment paradigm, and age predicted DFS. Neither >10-PYs, nor any other definition of tobacco use (e.g., current smoker or > 20-PYs) was predictive of DFS, overall survival, or disease-specific survival. Conversely, age nonsignificantly and significantly predicted adjusted DFS (adjusted HR[aHR]:1.02,95% CI:0.997-1.05, p = 0.08), overall survival (aHR 1.05; 95% CI: 1.02-1.08; p = 0.002) and disease-specific survival (aHR 1.04;95% CI: 0.99-1.09;p = 0.09). CONCLUSION: Other than age, patient-level influences may not be primary drivers of HPV+ OPC outcomes. Although limited by its modest sample size, our study suggests the significance of smoking has been overstated in this disease. These findings and the emerging literature collectively do not support risk-stratification employing the >10-PY threshold. LEVEL OF EVIDENCE: Level 4.


Assuntos
Alphapapillomavirus , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Humanos , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/cirurgia , Papillomaviridae , Infecções por Papillomavirus/complicações , Prognóstico , Estudos Retrospectivos , Fumar/efeitos adversos , Fumar/epidemiologia
5.
Cancer ; 127(6): 850-864, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33270909

RESUMO

BACKGROUND: Despite the significant societal burden of human papillomavirus (HPV)-associated cancers, clinical screening interventions for HPV-associated noncervical cancers are not available. Blood-based biomarkers may help close this gap in care. METHODS: Five databases were searched, 5687 articles were identified, and 3631 unique candidate titles and abstracts were independently reviewed by 2 authors; 702 articles underwent a full-text review. Eligibility criteria included the assessment of a blood-based biomarker within a cohort or case-control study. RESULTS: One hundred thirty-seven studies were included. Among all biomarkers assessed, HPV-16 E seropositivity and circulating HPV DNA were most significantly correlated with HPV-associated cancers in comparison with cancer-free controls. In most scenarios, HPV-16 E6 seropositivity varied nonsignificantly according to tumor type, specimen collection timing, and anatomic site (crude odds ratio [cOR] for p16+ or HPV+ oropharyngeal cancer [OPC], 133.10; 95% confidence interval [CI], 59.40-298.21; cOR for HPV-unspecified OPC, 25.41; 95% CI, 8.71-74.06; cOR for prediagnostic HPV-unspecified OPC, 59.00; 95% CI, 15.39-226.25; cOR for HPV-unspecified cervical cancer, 12.05; 95% CI, 3.23-44.97; cOR for HPV-unspecified anal cancer, 73.60; 95% CI, 19.68-275.33; cOR for HPV-unspecified penile cancer, 16.25; 95% CI, 2.83-93.48). Circulating HPV-16 DNA was a valid biomarker for cervical cancer (cOR, 15.72; 95% CI, 3.41-72.57). In 3 cervical cancer case-control studies, cases exhibited unique microRNA expression profiles in comparison with controls. Other assessed biomarker candidates were not valid. CONCLUSIONS: HPV-16 E6 antibodies and circulating HPV-16 DNA are the most robustly analyzed and most promising blood-based biomarkers for HPV-associated cancers to date. Comparative validity analyses are warranted. Variations in tumor type-specific, high-risk HPV DNA prevalence according to anatomic site and world region highlight the need for biomarkers targeting more high-risk HPV types. Further investigation of blood-based microRNA expression profiling appears indicated.


Assuntos
Anticorpos Antivirais/sangue , Neoplasias do Ânus/virologia , Biomarcadores/sangue , DNA Viral/sangue , Neoplasias Orofaríngeas/virologia , Infecções por Papillomavirus/complicações , Feminino , Papillomavirus Humano 16/isolamento & purificação , Humanos , Neoplasias do Colo do Útero/virologia
6.
Acc Chem Res ; 53(11): 2546-2557, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33063517

RESUMO

Immunotherapy has transformed the field of oncology and patient care. By leveraging the immune system of the host, immunostimulatory compounds exert a durable, personalized response against the patient's own tumor. Despite the clinical success, the overall response rate from current therapies (e.g., immune checkpoint inhibitors) remains low (∼20%) because tumors develop multiple resistance pathways at molecular, cellular, and microenvironmental levels. Unlike other oncologic therapies, harnessing antitumor immunity requires precise activation of a complex immunological system with multiple levels of regulation over its function. This requires the ability to exert control over immune cells in both intracellular compartments and various extracellular sites, such as the tumor microenvironment, in a spatiotemporally coordinated fashion.The immune system has evolved to sense and respond to nano- and microparticulates (e.g., viruses, bacteria) as foreign pathogens. Through the versatile control of composition, size, shape, and surface properties of nanoparticles, nano-immune-engineering approaches are uniquely positioned to mount appropriate immune responses against cancer. This Account highlights the development and implementation of ultra-pH-sensitive (UPS) nanoparticles in cancer immunotherapy with an emphasis on nanoscale cooperativity. Nanocooperativity has been manifested in many biological systems and processes (e.g., protein allostery, biomolecular condensation), where the system can acquire emergent properties distinct from the sum of individual parts acting in isolation.Using UPS nanoparticles as an example, we illustrate how all-or-nothing protonation cooperativity during micelle assembly/disassembly can be leveraged to augment the cancer-immunity cycle toward antitumor immunity. The cooperativity behavior enables instant and pH-triggered payload release and dose accumulation in acidic sites (e.g., endocytic organelles of antigen presenting cells, tumor microenvironment), intercepting specific immunological and tumor pathophysiological processes for therapy. These efforts include T cell activation in lymph nodes by coordinating cytosolic delivery of tumor antigens to dendritic cells with simultaneous activation of stimulator of interferon genes (STING), or tumor-targeted delivery of acidotic inhibitors to reprogram the tumor microenvironment and overcome T cell retardation. Each treatment strategy represents a nodal intervention in the cancer-immunity cycle, featuring the versatility of UPS nanoparticles. Overall, this Account aims to highlight nanoimmunology, an emerging cross field that exploits nanotechnology's unique synergy with immunology through nano-immune-engineering, for advancing cancer immunotherapy.


Assuntos
Imunoterapia , Nanopartículas/química , Neoplasias/terapia , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/metabolismo , Animais , Antígenos de Neoplasias/química , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Imunoterapia/métodos , Ativação Linfocitária , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Micelas , Nanopartículas/metabolismo , Nanotecnologia , Neoplasias/diagnóstico por imagem , Polímeros/química , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Microambiente Tumoral
7.
Ann Surg Oncol ; 27(8): 2591-2599, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32472408

RESUMO

BACKGROUND: The global pandemic of respiratory disease cause by the novel human coronavirus (SARS-CoV-2) has caused untold suffering, loss of life and upheaval in society. The pandemic has lead to massive redirection of health care resources to treat the surge of COVID-19 patients, and enforcement of social distancing to reduce the rate of transmission. METHODS: Editorial Board members provided observations of the implications of the pandemic on academic surgical oncology. RESULTS: Delivery of health care to other populations including cancer patients has been significantly disrupted. The implications both short term and long term threaten preservation of the academic mission in medicine at large, and certainly in the field of surgical oncology. CONCLUSIONS: The effects on surgical oncology training, research and clinical trials are major.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/complicações , Controle de Infecções/organização & administração , Neoplasias/cirurgia , Pneumonia Viral/complicações , Guias de Prática Clínica como Assunto/normas , Oncologia Cirúrgica/educação , Oncologia Cirúrgica/normas , COVID-19 , Infecções por Coronavirus/virologia , Humanos , Controle de Infecções/tendências , Neoplasias/epidemiologia , Neoplasias/virologia , Pandemias , Pneumonia Viral/virologia , SARS-CoV-2
8.
Oncology ; 98(3): 179-185, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31846962

RESUMO

BACKGROUND: HPV-positive head and neck squamous cell carcinoma (HPV+ HNSCC) demonstrates favorable outcomes compared to HPV-negative SCC, but distant metastases (DM) still occur. The pattern of DM in HPV+ HNSCC is unclear. METHODS: 1,494 HNSCC patients were treated from 2006 to 2012. Recurrence time and metastatic sites in HPV+ HNSCC (Group 1) were compared to patients with HPV-negative/unknown cancers arising in the hypopharynx, larynx, or glottis (Group 2) as well as to patients with HPV-negative/unknown cancers in theoral cavity, oropharynx, hard palate, or tonsil (Group 3). RESULTS: 7/109 (6.4%) patients with HPV+ HNSCC developed DM. The median time to metastases was 11 months. At a median follow-up of 18-25 months, there was no difference in the overall rate of DM for the HPV+ HNSCC group compared to Group 2 (HPV-/unknown) (p = 0.21) and Group 3 (HPV-/unknown) (p = 0.13). There was a significant difference in the rate of DM to the lung in the HPV+ HNSCC group compared to Group 2 (HPV-/unknown) (p = 0.012) and Group 3 (HPV-/unknown) (p = 0.002). CONCLUSIONS: There was no observed difference in the time to development of DM between the HPV-/unknown and HPV+ HNSCC groups. However, the HPV+ HNSCC group showed a higher rate of DM to the lung compared to the HPV-/unknown -HNSCC group (p = 0.002).


Assuntos
Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/virologia , Infecções por Papillomavirus/virologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/secundário , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Idoso , Progressão da Doença , Feminino , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/terapia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Fatores de Tempo , Resultado do Tratamento
9.
Cancer Invest ; 35(1): 23-31, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-27892728

RESUMO

Nab-paclitaxel might impact efficacy of radiation for head and neck (H&N) cancer. Nab-paclitaxel, cisplatin, cetuximab, and radiation were evaluated in patients with locally advanced head and neck cancer in this phase I/II trial. Median follow-up was 24 months for 34 patients. The maximum tolerated dose of nab-paclitaxel was 20 mg/m2 with 20 mg/m2 cisplatin and 250 mg/m2 cetuximab. The 2-year progression-free survival (PFS) was 60% (95% confidence interval (CI) 0.42, 0.78), local control 71% (95% CI 0.55, 0.87), and overall survival 68% (95% CI 0.50, 0.86). This is the first study evaluating these agents with radiation in humans, with similar 2-year PFS as historic control.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Idoso , Albuminas/administração & dosagem , Albuminas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cetuximab/administração & dosagem , Cetuximab/uso terapêutico , Cisplatino/administração & dosagem , Cisplatino/uso terapêutico , Terapia Combinada , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Paclitaxel/uso terapêutico , Análise de Sobrevida , Resultado do Tratamento
10.
AJR Am J Roentgenol ; 209(2): 289-303, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28731808

RESUMO

OBJECTIVE: The purpose of this article is to summarize the evidence for the value of PET/CT for the management of patients with head and neck squamous cell cancer and suggest best clinical practices. CONCLUSION: FDG PET/CT is a valuable imaging tool for identifying unknown primary tumors in patients with known cervical node metastases leading to management change and is the standard of care for the initial staging of stage III and IV head and neck squamous cell carcinomas (HNSCCs), for assessing therapy response when performed at least 12 weeks after chemoradiation therapy, and for avoiding unnecessary planned neck dissection. Neck dissection is avoided if PET/CT findings are negative-regardless of the size of the residual neck nodes-because survival outcomes are not compromised. FDG PET/CT is valuable in detecting recurrences and metastases during follow-up when suspected because of clinical symptoms and serves as a prognostic marker for patient survival outcomes, for 5 years. Using FDG PET/CT for routine surveillance of HNSCC after 6 months of treatment without any clinical suspicion should be discouraged.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/terapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Carcinoma de Células Escamosas/patologia , Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Metástase Neoplásica , Estadiamento de Neoplasias , Compostos Radiofarmacêuticos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Resultado do Tratamento
11.
J Appl Clin Med Phys ; 18(1): 157-163, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28291932

RESUMO

PURPOSE: We have initiated a multi-institutional phase I trial of 5-fraction stereotactic body radiotherapy (SBRT) for Stage III-IVa laryngeal cancer. We conducted this pilot dosimetric study to confirm potential utility of online adaptive replanning to preserve treatment quality. METHODS: We evaluated ten cases: five patients enrolled onto the current trial and five patients enrolled onto a separate phase I SBRT trial for early-stage glottic larynx cancer. Baseline SBRT treatment plans were generated per protocol. Daily cone-beam CT (CBCT) or diagnostic CT images were acquired prior to each treatment fraction. Simulation CT images and target volumes were deformably registered to daily volumetric images, the original SBRT plan was copied to the deformed images and contours, delivered dose distributions were re-calculated on the deformed CT images. All of these were performed on a commercial treatment planning system. In-house software was developed to propagate the delivered dose distribution back to reference CT images using the deformation information exported from the treatment planning system. Dosimetric differences were evaluated via dose-volume histograms. RESULTS: We could evaluate dose within 10 minutes in all cases. Prescribed coverage to gross tumor volume (GTV) and clinical target volume (CTV) was uniformly preserved; however, intended prescription dose coverage of planning treatment volume (PTV) was lost in 53% of daily treatments (mean: 93.9%, range: 83.9-97.9%). Maximum bystander point dose limits to arytenoids, parotids, and spinal cord remained respected in all cases, although variances in carotid artery doses were observed in a minority of cases. CONCLUSIONS: Although GTV and CTV SBRT dose coverage is preserved with in-room three-dimensional image guidance, PTV coverage can vary significantly from intended plans and dose to critical structures may exceed tolerances. Online adaptive treatment re-planning is potentially necessary and clinically applicable to fully preserve treatment quality. Confirmatory trial accrual and analysis remains ongoing.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Tomografia Computadorizada de Feixe Cônico/métodos , Neoplasias Laríngeas/cirurgia , Radiocirurgia/métodos , Planejamento da Radioterapia Assistida por Computador/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional , Neoplasias Laríngeas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Sistemas On-Line , Projetos Piloto , Prognóstico , Estudos Prospectivos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos
15.
Nat Mater ; 13(2): 204-12, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24317187

RESUMO

Stimuli-responsive nanomaterials are increasingly important in a variety of applications such as biosensing, molecular imaging, drug delivery and tissue engineering. For cancer detection, a paramount challenge still exists in the search for methods that can illuminate tumours universally regardless of their genotypes and phenotypes. Here we capitalized on the acidic, angiogenic tumour microenvironment to achieve the detection of tumour tissues in a wide variety of mouse cancer models. This was accomplished using ultra pH-sensitive fluorescent nanoprobes that have tunable, exponential fluorescence activation on encountering subtle, physiologically relevant pH transitions. These nanoprobes were silent in the circulation, and then strongly activated (>300-fold) in response to the neovasculature or to the low extracellular pH in tumours. Thus, we have established non-toxic, fluorescent nanoreporters that can nonlinearly amplify tumour microenvironmental signals, permitting the identification of tumour tissue independently of histological type or driver mutation, and detection of acute treatment responses much more rapidly than conventional imaging approaches.


Assuntos
Corantes Fluorescentes , Aumento da Imagem/métodos , Microscopia de Fluorescência/métodos , Imagem Molecular/métodos , Nanocápsulas , Neoplasias Experimentais/patologia , Microambiente Tumoral , Animais , Linhagem Celular Tumoral , Feminino , Corantes Fluorescentes/química , Camundongos , Camundongos Nus , Nanocápsulas/química , Dinâmica não Linear
16.
J Am Chem Soc ; 136(31): 11085-92, 2014 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-25020134

RESUMO

pH is an important physiological parameter that plays a critical role in cellular and tissue homeostasis. Conventional small molecular pH sensors (e.g., fluorescein, Lysosensor) are limited by broad pH response and restricted fluorescent emissions. Previously, we reported the development of ultra-pH-sensitive (UPS) nanoprobes with sharp pH response using fluorophores with small Stokes shifts (<40 nm). In this study, we expand the UPS design to a library of nanoprobes with operator-predetermined pH transitions and wide fluorescent emissions (400-820 nm). A copolymer strategy was employed to fine tune the hydrophobicity of the ionizable hydrophobic block, which led to a desired transition pH based on standard curves. Interestingly, matching the hydrophobicity of the monomers was critical to achieve a sharp pH transition. To overcome the fluorophore limitations, we introduced copolymers conjugated with fluorescence quenchers (FQs). In the micelle state, the FQs effectively suppressed the emission of fluorophores regardless of their Stokes shifts and further increased the fluorescence activation ratios. As a proof of concept, we generated a library of 10 nanoprobes each encoded with a unique fluorophore. The nanoprobes cover the entire physiologic range of pH (4-7.4) with 0.3 pH increments. Each nanoprobe maintained a sharp pH transition (on/off < 0.25 pH) and high fluorescence activation ratio (>50-fold between on and off states). The UPS library provides a useful toolkit to study pH regulation in many pathophysiological indications (e.g., cancer, lysosome catabolism) as well as establishing tumor-activatable systems for cancer imaging and drug delivery.


Assuntos
Corantes Fluorescentes/química , Nanoestruturas/química , Concentração de Íons de Hidrogênio , Polimerização , Polímeros/química , Espectrometria de Fluorescência
18.
J Biomed Opt ; 29(1): 016005, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38239390

RESUMO

Significance: Polarized hyperspectral microscopes with the capability of full Stokes vector imaging have potential for many biological and medical applications. Aim: The aim of this study is to investigate polarized hyperspectral imaging (PHSI) for improving the visualization of collagen fibers, which is an important biomarker related to tumor development, and improving the differentiation of normal and tumor cells on pathologic slides. Approach: We customized a polarized hyperspectral microscopic imaging system comprising an upright microscope with a motorized stage, two linear polarizers, two liquid crystal variable retarders (LCVRs), and a compact SnapScan hyperspectral camera. The polarizers and LCVRs worked in tandem with the hyperspectral camera to acquire polarized hyperspectral images, which were further used to calculate four Stokes vectors: S0, S1, S2, and S3. Synthetic RGB images of the Stokes vectors were generated for the visualization of cellular components in PHSI images. Regions of interest of collagen, normal cells, and tumor cells in the synthetic RGB images were selected, and spectral signatures of the selected components were extracted for comparison. Specifically, we qualitatively and quantitatively investigated the enhanced visualization and spectral characteristics of dense fibers and sparse fibers in normal stroma tissue, fibers accumulated within tumors, and fibers accumulated around tumors. Results: By employing our customized polarized hyperspectral microscope, we extract the spectral signatures of Stokes vector parameters of collagen as well as of tumor and normal cells. The measurement of Stokes vector parameters increased the image contrast of collagen fibers and cells in the slides. Conclusions: With the spatial and spectral information from the Stokes vector data cubes (S0, S1, S2, and S3), our PHSI microscope system enhances the visualization of tumor cells and tumor microenvironment components, thus being beneficial for pathology and oncology.


Assuntos
Neoplasias de Cabeça e Pescoço , Microscopia , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Microscopia/métodos , Colágeno , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Microambiente Tumoral
19.
Artigo em Inglês | MEDLINE | ID: mdl-38711533

RESUMO

Head and neck squamous cell carcinoma (HNSCC) has a high mortality rate. In this study, we developed a Stokes-vector-derived polarized hyperspectral imaging (PHSI) system for H&E-stained pathological slides with HNSCC and built a dataset to develop a deep learning classification method based on convolutional neural networks (CNN). We use our polarized hyperspectral microscope to collect the four Stokes parameter hypercubes (S0, S1, S2, and S3) from 56 patients and synthesize pseudo-RGB images using a transformation function that approximates the human eye's spectral response to visual stimuli. Each image is divided into patches. Data augmentation is applied using rotations and flipping. We create a four-branch model architecture where each branch is trained on one Stokes parameter individually, then we freeze the branches and fine-tune the top layers of our model to generate final predictions. Our results show high accuracy, sensitivity, and specificity, indicating that our model performed well on our dataset. Future works can improve upon these results by training on more varied data, classifying tumors based on their grade, and introducing more recent architectural techniques.

20.
ACS Nano ; 18(26): 16632-16647, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38900677

RESUMO

While local nanoparticle delivery to lymph nodes is well studied, there are few design criteria for intravenous delivery to the entire lymph node repertoire. In this study, we investigated the effect of NP pH transition on lymph node targeting by employing a series of ultra-pH-sensitive (UPS) polymeric micelles. The UPS library responds to pH thresholds (pKa 6.9, 6.2, and 5.3) over a range of physiological pH. We observed a dependence of intravenous lymph node targeting on micelle pH transition. UPS6.9 (subscript indicates pKa) shows poor lymph node delivery, while UPS5.3 delivers efficiently to lymph node sets. We investigated targeting mechanisms of UPS5.3, observing an accumulation among lymph node lymphatics and a dependence on lymph node-resident macrophages. To overcome the pH-threshold barrier, which limits UPS6.9, we rationally designed a nanoparticle coassembly of UPS6.9 with UPS5.3, called HyUPS. The HyUPS micelle retains the constitutive pH transitions of each polymer, showing stepwise responses to discrete pH thresholds. We demonstrate that HyUPS improves UPS6.9 delivery to lymph nodes, extending this platform for disease detection of lymph node metastasis.


Assuntos
Linfonodos , Micelas , Concentração de Íons de Hidrogênio , Linfonodos/metabolismo , Animais , Camundongos , Nanopartículas/química , Polímeros/química , Feminino , Sistemas de Liberação de Medicamentos
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