20,888 research outputs found
Breast cancer as photodynamic therapy target: Enhanced therapeutic efficiency by overview of tumor complexity
Photodynamic therapy is a minimally invasive and clinically approved procedure for eliminating selected malignant cells with specific light activation of a photosensitizer agent. Whereas interstitial and intra-operative approaches have been investigated for the ablation of a broad range of superficial or bulky solid tumors such as breast cancer, the majority of approved photodynamic therapy protocols are for the treatment of superficial lesions of skin and luminal organs. This review article will discuss recent progress in research focused mainly on assessing the efficacies of various photosensitizers used in photodynamic therapy, as well as the combinatory strategies of various therapeutic modalities for improving treatments of parenchymal and/or stromal tissues of breast cancer solid tumors. Cytotoxic agents are used in cancer treatments for their effect on rapidly proliferating cancer cells. However, such therapeutics often lack specificity, which can lead to toxicity and undesirable side effects. Many approaches are designed to target tumors. Selective therapies can be established by focusing on distinctive intracellular (receptors, apoptotic pathways, multidrug resistance system, nitric oxide-mediated stress) and environmental (glucose, pH) differences between tumor and healthy tissue. A rational design of effective combination regimens for breast cancer treatment involves a better understanding of the mechanisms and molecular interactions of cytotoxic agents that underlie drug resistance and sensitivity.Fil: Lamberti, MarĂa Julia. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas, FisicoquĂmicas y Naturales. Departamento de BiologĂa Molecular. SecciĂłn QuĂmica BiolĂłgica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Rumie Vittar, Natalia Belen. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas, FisicoquĂmicas y Naturales. Departamento de BiologĂa Molecular. SecciĂłn QuĂmica BiolĂłgica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Rivarola, Viviana. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas, FisicoquĂmicas y Naturales. Departamento de BiologĂa Molecular. SecciĂłn QuĂmica BiolĂłgica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentin
Populational adaptive evolution, chemotherapeutic resistance and multiple anti-cancer therapies
Resistance to chemotherapies, particularly to anticancer treatments, is an
increasing medical concern. Among the many mechanisms at work in cancers, one
of the most important is the selection of tumor cells expressing resistance
genes or phenotypes. Motivated by the theory of mutation-selection in adaptive
evolution, we propose a model based on a continuous variable that represents
the expression level of a resistance gene (or genes, yielding a phenotype)
influencing in healthy and tumor cells birth/death rates, effects of
chemotherapies (both cytotoxic and cytostatic) and mutations. We extend
previous work by demonstrating how qualitatively different actions of
chemotherapeutic and cytostatic treatments may induce different levels of
resistance. The mathematical interest of our study is in the formalism of
constrained Hamilton-Jacobi equations in the framework of viscosity solutions.
We derive the long-term temporal dynamics of the fittest traits in the regime
of small mutations. In the context of adaptive cancer management, we also
analyse whether an optimal drug level is better than the maximal tolerated
dose
Aerosolization of nanotherapeutics as a newly emerging treatment regimen for peritoneal carcinomatosis
Recent advances in locoregional chemotherapy have opened the door to new approaches for the clinical management of peritoneal carcinomatosis (PC) by facilitating the delivery of anti-neoplastic agents directly to the tumor site, while mitigating adverse effects typically associated with systemic administration. In particular, an innovative intra-abdominal chemotherapeutic approach, known as Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC), was recently introduced to the intraperitoneal (IP) therapy regimens as a palliative therapeutic option in patients with PC, presumably providing a better drug distribution pattern together with deeper drug penetration into tumor nodules within the peritoneal space. Furthermore, the progress of nanotechnology in the past few decades has prompted the application of different nanomaterials in IP cancer therapy, offering new possibilities in this field ranging from an extended retention time to sustained drug release in the peritoneal cavity. This review highlights the progress, challenges, and opportunities in utilizing cancer nanotherapeutics for locoregional drug delivery, with a special emphasis on the aerosolization approach for intraperitoneal therapies
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