Resistencias del carcinoma basocelular a la terapia fotodinámica con metil-aminolevulinato

Introducción: la terapia fotodinámica (TFD) con metil-aminolevulinato (MAL), es uno de los tratamientos no invasivos más usados en el tratamiento del Carcinoma Basocelular (CBC). Sus principales ventajas son la alta tasa de respuestas completas, a los tres meses, del 91% y a los 5 años del 76% con un excelente resultado cosmético y una gran satisfacción por parte del paciente. Aunque las tasas de respuesta a la TFD son altas existen algunos CBCs que no responden adecuadamente. El estudio de las diferencias clínicas, histológicas y biológicas de los CBCs en su respuesta a la TFD nos ayudará a conocer mejor su mecanismo de acción, así como aumentar su eficacia y eficiencia permitiendo la selección de los pacientes.Material y métodos: estudio observacional con recopilación de datos de forma retrospectiva en el que se han utilizado lesiones de pacientes compatibles con CBC que fueron tratados con TFD con MAL en la Unidad de Dermatología del Hospital San Jorge de Huesca desde el 1 de Enero de 2006 al 31 de Diciembre de 2015. Hemos recogido variables demográficas (edad, sexo, localización del tumor, tamaño, fototipo, factores predisponentes), parámetros histológicos clásicos en aquellos que tenían biopsia previa y/o curetaje, siempre que hubiese material histológico suficiente, (espesor tumoral, estroma peritumoral, pérdida de empalizada periférica, pleomorfismo, ulceración, presencia del infiltrado linfocitario intratumoral, invasión perineural, así como la presencia de elastosis). A continuación, hemos realizado tinciones de P53, Ki-67, CD-31, COX2, EGFR, survivina y β-catenina. Posteriormente se ha evaluado la respuesta a TFD en las líneas celulares de cáncer de CBC de ratón, ASZ y células BSZ, ambas se aislaron de ratones heterocigotos para el gen Ptch+/- y las segundas carecen del gen P53.Resultados: se incluyeron en el estudio un total de 390 Carcinomas Basocelulares en 182 pacientes. La tasa de respuesta global fue de 82,8%, con un tiempo medio de seguimiento de 35,96 meses (DE=23,46), un mínimo de 3 meses y un máximo de 6 años. Las variables clínicas de los CBCs que se asocian con mala respuesta a la TFD con MAL son: la variante nodular, la localización en área H, edad más avanzada, los fototipos IV, V y VI de Fitzpatrick o los pacientes que han recibido un mayor número de sesiones. Se evaluó la histología de 63 casos de CBCs tratados con TFD con MAL, de estos 49 muestras pertenecían a CBCs respondedores y 14 a especímenes de CBCs no respondedores. En relación a las variables anatomo-patológicas, la presencia de infiltrado inflamatorio linfocítico peritumoral previo es un factor predictor de buena respuesta a la TFD con MAL. La inmunoreactividad positiva a P53 en CBC es un factor predictor de buena respuesta, por el contrario el patrón de tinción de β-catenina con refuerzo periférico de los islotes de células basaloides se asocia a resistencia del carcinoma basocelular a la TFD con MAL. La línea celular ASZ difiere de la línea celular BSZ en que expresa más P53 y al ser ambas líneas sometidas a tratamiento con TFD con MAL, la línea celular ASZ presenta una viabilidad menor que BSZ.Conclusiones: consideramos que hay evidencia suficiente para concluir que el subtipo histológico de CBC nodular frente a la variante superficial es un factor predictor de mala respuesta, sin embargo tener una edad inferior a 63 años, la inmunotinción positiva para P53 y la presencia de infiltrado inflamatorio linfocítico peritumoral son factores predictores de buena respuesta del CBC a la TFD con MAL.<br /

Selective Oxidative Dearomatization of Angular Tetracyclic Phenols by Controlled Irradiation under Air: Synthesis of an Angucyclinone-Type Double Peroxide with Anticancer Properties

Angular tetracyclic p-peroxyquinols, p-quinols and a pentacyclic double peroxide, showing anticancer properties, were Selective oxidative dearomatization of angular tetracyclic phenols by controlled irradiation under air: synthesis of an angucyclinone‐type double peroxide with anticancer properties María J. Cabrera-Afonso,a Silvia R. Lucena,b Ángeles Juarranz,b Antonio Urbano,*a,c M. Carmen Carreño*a,c aDepartamento de Química Orgánica, Universidad Autónoma de Madrid (UAM), Cantoblanco, 28049-Madrid, Spain. bDepartamento de Biología, UAM, Cantoblanco, 28049-Madrid, Spain. cInstitute for Advanced Research in Chemical Sciences (IAdChem), UAM, Cantoblanco, 28049-Madrid, Spain. Supporting Information Placeholder synthesized from the corresponding phenols by an environmentally friendly solvent- and wavelength-controlled irradiation under air in the absence of an external photosensitizerWe thank MINECO (Grants CTQ2017-83309-P, CTQ2014-53894R and FIS PI15/00974) for financial suppor

The effect of Fernblock® in preventing blue-light-induced oxidative stress and cellular damage in retinal pigment epithelial cells is associated with NRF2 induction

Blue light exposure of the ocular apparatus is currently rising. This has motivated a growing concern about potential deleterious effects on different eye structures. To address this, ARPE-19 cells were used as a model of the retinal pigment epithelium and subjected to cumulative expositions of blue light. The most relevant cellular events previously associated with bluelight-induced damage were assessed, including alterations in cell morphology, viability, cell proliferation, oxidative stress, inflammation, and the induction of DNA repair cellular mechanisms. Consistent with previous reports, our results provide evidence of cellular alterations resulting from repeated exposure to blue light irradiation. In this context, we explored the potential protective properties of the vegetal extract from Polypodium leucotomos, Fernblock® (FB), using the widely known treatment with lutein as a reference for comparison. The only changes observed as a result of the sole treatment with either FB or lutein were a slight but significant increase in γH2AX+ cells and the raise in the nuclear levels of NRF2. Overall, our f indings indicate that the treatment with FB (similarly to lutein) prior to blue light irradiation can alleviate blue-light-induced deleterious effects in RPE cells, specifically preventing the drop in both cell viability and percentage of EdU+ cells, as well as the increase in ROS generation, percentage of γH2AX+ nuclei (more efficiently with FB), and TNF-α secretion (the latter restored only by FB to similar levels to those of the control). On the contrary, the induction in the P21 expression upon blue light irradiation was not prevented neither by FB nor by lutein. Notably, the nuclear translocation of NRF2 induced by blue light was similar to that observed in cells pre-treated with FB, while lutein pre-treatment resulted in nuclear NRF2 levels similar to control cells, suggesting key differences in the mechanism of cellular protection exerted by these compounds. These results may represent the foundation ground for the use of FB as a new ingredient in the development of alternative prophylactic strategies for blue-light-associated diseases, a currently rising medical interes

Metformin overcomes metabolic reprogramming-induced resistance of skin squamous cell carcinoma to photodynamic therapy

Cancer metabolic reprogramming promotes resistance to therapies. In this study, we addressed the role of the Warburg effect in the resistance to photodynamic therapy (PDT) in skin squamous cell carcinoma (sSCC). Furthermore, we assessed the effect of metformin treatment, an antidiabetic type II drug that modulates metabolism, as adjuvant to PDT. Methods: For that, we have used two human SCC cell lines: SCC13 and A431, called parental (P) and from these cell lines we have generated the corresponding PDT resistant cells (10GT). Results: Here, we show that 10GT cells induced metabolic reprogramming to an enhanced aerobic glycolysis and reduced activity of oxidative phosphorylation, which could influence the response to PDT. This result was also confirmed in P and 10GT SCC13 tumors developed in mice. The treatment with metformin caused a reduction in aerobic glycolysis and an increase in oxidative phosphorylation in 10GT sSCC cells. Finally, the combination of metformin with PDT improved the cytotoxic effects on P and 10GT cells. The combined treatment induced an increase in the protoporphyrin IX production, in the reactive oxygen species generation and in the AMPK expression and produced the inhibition of AKT/mTOR pathway. The greater efficacy of combined treatments was also seen in vivo, in xenografts of P and 10GT SCC13 cells. Conclusions: Altogether, our results reveal that PDT resistance implies, at least partially, a metabolic reprogramming towards aerobic glycolysis that is prevented by metformin treatment. Therefore, metformin may constitute an excellent adjuvant for PDT in sSCCThis research was supported by Spanish grants from Instituto de Salud Carlos III MINECO and Feder Funds (FIS PI15/00974; PI18/00858 and PI18/00708) and Ministerio de Ciencia, Innovación y Universidades (PID2019-108674RB-100

Tumor microenvironment in non-melanoma skin cancer resistance to photodynamic therapy

Non-melanoma skin cancer has recently seen an increase in prevalence, and it is estimated that this grow will continue in the coming years. In this sense, the importance of therapy effectiveness has increased, especially photodynamic therapy. Photodynamic therapy has attracted much attention as a minimally invasive, selective and repeatable approach for skin cancer treatment and prevention. Although its high efficiency, this strategy has also faced problems related to tumor resistance, where the tumor microenvironment has gained a well-deserved role in recent years. Tumor microenvironment denotes a wide variety of elements, such as cancer-associated fibroblasts, immune cells, endothelial cells or the extracellular matrix, where their interaction and the secretion of a wide diversity of cytokines. Therefore, the need of designing new strategies targeting elements of the tumor microenvironment to overcome the observed resistance has become evident. To this end, in this review we focus on the role of cancer-associated fibroblasts and tumor-associated macrophages in the resistance to photodynamic therapy. We are also exploring new approaches consisting in the combination of new and old drugs targeting these cells with photodynamic therapy to enhance treatment outcomes of non-melanoma skin cance

In vitro 5-Fluorouracil resistance produces enhanced photodynamic therapy damage in SCC and tumor resistance in BCC

Non-melanoma skin cancer (NMSC) is the most common malignancy worldwide, with rising incidence in the recent years. It includes basal cell carcinoma (BCC), and squamous cell carcinoma (SCC). Several non-invasive therapies have been developed for its treatment such as topical 5-Fluorouracil (5FU) and photodynamic therapy (PDT), among others. Despite both are appropriated for NMSC treatment, recurrence cases have been reported. To prevent this, in this work we explore the potential of the combination of PDT and 5FU to treat SCC and BCC. First we evaluate the efficacy of PDT in cells resistant to 5FU. For this purpose, we use SCC-13 and CSZ-1 cells, obtained from a human SCC and a murine BCC, respectively. We first induced 5FU resistance in these cell lines by repeated treatments with the drug and then, the efficacy to PDT was evaluated. The results obtained indicated that SCC-5FU resistant cells were sensible to PDT administration, whereas BCC-5FU resistant cells were also resistant to PDT. The observed responses in both cell lines are in concordance to Protoporphyrin IX (PpIX) and reactive oxygen species (ROS) levels produced after the incubation with MAL and subsequent light exposure. The obtained data support the fact that PDT seems to be an appropriate therapeutic option to be administered after 5FU resistance in SCC. However, PDT would not be a choice therapy for resistant BCC cells to 5FUThis research was supported by Spanish grants from Instituto de Salud Carlos III Ministerio de Ciencia e innovacion, ´ and Feder Funds (FIS PI18/00708,PI21/00315 and PI21/00953

Tgfβ1 secreted by cancer-associated fibroblasts as an inductor of resistance to photodynamic therapy in squamous cell carcinoma cells

SIMPLE SUMMARY: Photodynamic therapy (PDT) is used for the treatment of in situ cutaneous squamous cell carcinoma (cSCC), the second most common form of skin cancer, as well as for its precancerous form, actinic keratosis. However, relapses after the treatment can occur. Transforming growth factor β1 (TGFβ1) produced by cancer-associated fibroblasts (CAFs) in the tumor microenvironment has been pointed as a key player in the development of cSCC resistance to other therapies, such as chemotherapy. Here, we demonstrate that TGFβ1 produced by CAFs isolated from patients with cSCC can drive resistance to PDT in SCC cells. This finding opens up novel possibilities for strategy optimization in the field of cSCC resistance to PDT and highlights CAF-derived TGFβ1 as a potential target to improve the efficacy of PDT. ABSTRACT: As an important component of tumor microenvironment, cancer-associated fibroblasts (CAFs) have lately gained prominence owing to their crucial role in the resistance to therapies. Photodynamic therapy (PDT) stands out as a successful therapeutic strategy to treat cutaneous squamous cell carcinoma. In this study, we demonstrate that the transforming growth factor β1 (TGFβ1) cytokine secreted by CAFs isolated from patients with SCC can drive resistance to PDT in epithelial SCC cells. To this end, CAFs obtained from patients with in situ cSCC were firstly characterized based on the expression levels of paramount markers as well as the levels of TGFβ1 secreted to the extracellular environment. On a step forward, two established human cSCC cell lines (A431 and SCC13) were pre-treated with conditioned medium obtained from the selected CAF cultures. The CAF-derived conditioned medium effectively induced resistance to PDT in A431 cells through a reduction in the cell proliferation rate. This resistance effect was recapitulated by treating with recombinant TGFβ1 and abolished by using the SB525334 TGFβ1 receptor inhibitor, providing robust evidence of the role of TGFβ1 secreted by CAFs in the development of resistance to PDT in this cell line. Conversely, higher levels of recombinant TGFβ1 were needed to reduce cell proliferation in SCC13 cells, and no induction of resistance to PDT was observed in this cell line in response to CAF-derived conditioned medium. Interestingly, we probed that the comparatively higher intrinsic resistance to PDT of SCC13 cells was mediated by the elevated levels of TGFβ1 secreted by this cell line. Our results point at this feature as a promising biomarker to predict both the suitability of PDT and the chances to optimize the treatment by targeting CAF-derived TGFβ1 in the road to a more personalized treatment of particular cSCC tumors