Image-Based Quantification of Benzoporphyrin Derivative Uptake, Localization, and Photobleaching in 3D Tumor Models, for Optimization of PDT Parameters

Photodynamic therapy (PDT) is a light-based treatment modality in which wavelength specific activation of a photosensitizer (PS) generates cytotoxic response in the irradiated region. PDT response is critically dependent on several parameters including light dose, PS dose, uptake time, fluence rate, and the mode of light delivery. While the systematic optimization of these treatment parameters can be complex, it also provides multiple avenues for en- hancement of PDT efficacy under diverse treatment conditions, provided that a rational framework is established to quantify the impact of parameter selection upon treatment re- sponse. Here we present a theranostic technique, combining the inherent ability of the PS to serve simultaneously as a therapeutic and imaging agent, with the use of image-based treatment assessment in three dimensional (3D) in vitro tumor models, to comprise a platform to evaluate the impact of PDT parameters on treatment outcomes. We use this approach to visualize and quantify the uptake, localization, and photobleaching of the PS benzoporphyrin derivative monoacid ring-A (BPD) in a range of treatment conditions with varying uptake times as well as continuous and fractionated light delivery regimens in 3D cultures of AsPC-1 and PANC-1 cells. Informed by photobleaching patterns and correlation with cytotoxic re- sponse, asymmetric fractionated light delivery at 4 hours BPD uptake was found to be the most effective regimen assessed. Quantification of the spatial profile of cell killing within multicellular nodules revealed that these conditions also achieve the highest depth of cyto- toxicity along the radial axis of 3D nodules. The framework introduced here provides a means for systematic assessment of PDT treatment parameters in biologically relevant 3D tumor models with potential for broader application to other systems

Impact of Treatment Response Metrics on Photodynamic Therapy Planning and Outcomes in a Three-Dimensional Model of Ovarian Cancer

Common methods to characterize treatment efficacy based on morphological imaging may misrepresent outcomes and exclude effective therapies. Using a three-dimensional model of ovarian cancer, two functional treatment response metrics are used to evaluate photodynamic therapy (PDT) efficacy: total volume, calculated from viable and nonviable cells, and live volume, calculated from viable cells. The utility of these volume-based metrics is corroborated using independent reporters of photodynamic activity: viability, a common fluorescence-based ratiometric analysis, and photosensitizer photobleaching, which is characterized by a loss of fluorescence due in part to the production of reactive species during PDT. Live volume correlated with both photobleaching and viability, suggesting that it was a better reporter of PDT efficacy than total volume, which did not correlate with either metric. Based on these findings, live volume and viability are used to probe the susceptibilities of tumor populations to a range of PDT dose parameters administered using 0.25, 1, and 10 μM benzoporphyrin derivative (BPD). PDT with 0.25 μM BPD produces the most significant reduction in live volume and viability and mediates a substantial shift toward small nodules. Increasingly sophisticated bioengineered models may complement current treatment planning approaches and provide unique opportunities to critically evaluate key parameters including metrics of therapeutic response

An imaging-based platform for high-content, quantitative evaluation of therapeutic response in 3D tumour models

While it is increasingly recognized that three-dimensional (3D) cell culture models recapitulate drug responses of human cancers with more fidelity than monolayer cultures, a lack of quantitative analysis methods limit their implementation for reliable and routine assessment of emerging therapies. Here, we introduce an approach based on computational analysis of fluorescence image data to provide high-content readouts of dose-dependent cytotoxicity, growth inhibition, treatment-induced architectural changes and size-dependent response in 3D tumour models. We demonstrate this approach in adherent 3D ovarian and pancreatic multiwell extracellular matrix tumour overlays subjected to a panel of clinically relevant cytotoxic modalities and appropriately designed controls for reliable quantification of fluorescence signal. This streamlined methodology reads out the high density of information embedded in 3D culture systems, while maintaining a level of speed and efficiency traditionally achieved with global colorimetric reporters in order to facilitate broader implementation of 3D tumour models in therapeutic screening

Displasia diastrófica: diagnóstico pré-natal e revisão da literatura

CONTEXT Diastrophic dysplasia is a type of osteochondrodysplasia caused by homozygous mutation in the gene DTDST (diastrophic dysplasia sulfate transporter gene). Abnormalities occurring particularly in the skeletal and cartilaginous system are typical of the disease, which has an incidence of 1 in 100,000 live births. CASE REPORT The case of a pregnant woman, without any consanguineous relationship with her husband, whose fetus was diagnosed with skeletal dysplasia based on ultrasound findings and DNA tests, is described. An obstetric ultrasound scan produced in the 16th week of gestation revealed characteristics that guided the clinical diagnosis. Prominent among these characteristics were rhizomelia of the lower and upper limbs (shortening of the proximal portions) and mesomelia (shortening of the intermediate portions). Both upper limbs showed marked curvature, with the first finger of the upper limbs in abduction and clinodactyly of the fifth finger. Molecular analysis using the polymerase chain reaction (PCR) and gene sequencing detected mutations that had already been described in the literature for the gene DTDST, named c.862C > T and c.2147_2148insCT. Therefore, the fetus was a compound heterozygote, carrying two different mutations. CONCLUSIONS Prenatal diagnosis of this condition allowed a more realistic interpretation of the prognosis, and of the couple's reproductive future. This case report shows the contribution of molecular genetics towards the prenatal diagnosis, for which there are few descriptions in the literature.CONTEXTO A displasia diastrófica é uma osteocondrodisplasia causada por mutação homozigótica no gene DTDST (diastrophic dysplasia sulfate transporter gene). As alterações, principalmente nos sistemas esquelético e cartilaginoso, são típicas dessa doença, que tem uma incidência de 1 em 100.000 nascidos vivos. RELATO DO CASO Descreve-se o caso de uma mulher gestante, sem relação consanguínea com o seu marido, cujo feto foi diagnosticado com displasia esquelética baseado na ultrassonografia e em testes de DNA. A ultrassonografia obstétrica, realizada na 16a semana, revelou características que guiaram o diagnóstico clínico. Entre elas, se destacam os membros inferiores e superiores com rizomelia (encurtamento das porções proximais) e mesomelia (encurtamento das porções intermediárias), ambos os membros superiores mostraram acentuada flexão, o primeiro dedo em abdução nas extremidades superiores e clinodactilia do quinto dedo. A análise molecular pela reação em cadeia da polimerase (PCR) e o sequenciamento gênico detectou mutações já descritas na literatura para o gene DTDST, chamado c.862C > T e c.2147_2148insCT. Portanto, o feto é um heterozigoto composto, carreando duas mutações diferentes. CONCLUSÕES O diagnóstico pré-natal dessa condição permite uma interpretação mais realista do prognóstico e do futuro reprodutivo do casal. Este relato de caso mostra a contribuição da genética molecular no diagnóstico pré-natal, com poucas descrições na literatura.Faculdades Integradas do Brasil (UniBrasil)Universidade Federal do Paraná (UFPR) Department of Gynecology and ObstetricsCentro de Diagnósticos (CEDUS)Pontifícia Universidade Católica do Paraná (PUCPR) Health and Biosciences School (ESB) Graduate Program in Health Science (PPGCS)Faculdades Integradas do Brasil (UniBrasil) Biomedicine CourseUniversidade Federal de São Paulo (UNIFESP) Department of ObstetricsUNIFESP, Department of ObstetricsSciEL

Neoadjuvant photodynamic therapy augments immediate and prolonged oxaliplatin efficacy in metastatic pancreatic cancer organoids

Effective treatment of advanced metastatic disease remains the primary challenge in the management of inoperable pancreatic cancer. Current therapies such as oxaliplatin (OxPt)-based chemotherapy regimens (FOLFIRINOX) provide modest short-term survival improvements, yet with significant toxicity. Photodynamic therapy (PDT), a light-activated cancer therapy, demonstrated clinical promise for pancreatic cancer treatment and enhances conventional chemotherapies with non-overlapping toxicities. This study investigates the capacity of neoadjuvant PDT using a clinically-approved photosensitizer, benzoporphyrin derivative (BPD, verteporfin), to enhance OxPt efficacy in metastatic pancreatic cancer. Treatment effects were evaluated in organotypic three-dimensional (3D) cultures, clinically representative models that bridge the gap between conventional cell cultures and in vivo models. The temporally-spaced, multiparametric analyses demonstrated a superior efficacy for combined PDT+OxPt compared to each monotherapy alone, which was recapitulated on different organotypic pancreatic cancer cultures. The therapeutic benefit of neoadjuvant PDT to OxPt chemotherapy materialized in a time-dependent manner, reducing residual viable tissue and tumor viability in a manner not achievable with OxPt or PDT alone. These findings emphasize the need for intelligent combination therapies and relevant models to evaluate the temporal kinetics of interactions between mechanistically-distinct treatments and highlight the promise of PDT as a neoadjuvant treatment for disseminated pancreatic cancer

Clinical assessment of a low-cost, hand-held, smartphone-attached intraoral imaging probe for 5-aminolevulinic acid photodynamic therapy monitoring and guidance

SIGNIFICANCE: India has one of the highest rates of oral squamous cell carcinoma (OSCC) in the world, with an incidence of 15 per 100,000 and more than 70,000 deaths per year. The problem is exacerbated by a lack of medical infrastructure and routine screening, especially in rural areas. New technologies for oral cancer detection and timely treatment at the point of care are urgently needed. AIM: Our study aimed to use a hand-held smartphone-coupled intraoral imaging device, previously investigated for autofluorescence (auto-FL) diagnostics adapted here for treatment guidance and monitoring photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) fluorescence (FL). APPROACH: A total of 12 patients with 14 buccal mucosal lesions having moderately/well-differentiated micro-invasive OSCC lesions (1.65 at the time of treatment were associated with successful outcomes. CONCLUSION: These results indicate the utility of a low-cost, handheld intraoral imaging probe for image-guided PDT and treatment monitoring while also laying the groundwork for an integrated approach, combining cancer screening and treatment with the same hardware