A rare case of meloxicam-induced pseudoporphyria.

Drug-induced pseudoporphyria is commonly linked to nonsteroidal anti-inflammatory drugs (NSAIDs) such as naproxen, oxaprozin, ketoprofen, and ibuprofen. The NSAID meloxicam is not a commonly reported inciting agent. We report a case of meloxicam-induced pseudoporphyria in a 55-year-old woman with a past medical history of hypertension, hyperlipidemia, gastroesophageal reflux disease, and osteoarthritis. She presented to the clinic with tense and denuded bullae on her dorsal feet, which was diagnosed as pseudoporphyria after further workup. Upon evaluating the patient's medication history, meloxicam was identified as the most likely inciting agent. The patient's condition resolved with the discontinuation of this medication. Our findings can help dermatologists effectively diagnose and treat meloxicam-induced pseudoporphyria in patients with similar cases.

Nonlinear response to cancer nanotherapy due to macrophage interactions revealed by mathematical modeling and evaluated in a murine model via CRISPR-modulated macrophage polarization.

Tumor-associated macrophages (TAMs) have been shown to both aid and hinder tumor growth, with patient outcomes potentially hinging on the proportion of M1, pro-inflammatory/growth-inhibiting, to M2, growth-supporting, phenotypes. Strategies to stimulate tumor regression by promoting polarization to M1 are a novel approach that harnesses the immune system to enhance therapeutic outcomes, including chemotherapy. We recently found that nanotherapy with mesoporous particles loaded with albumin-bound paclitaxel (MSV-nab-PTX) promotes macrophage polarization towards M1 in breast cancer liver metastases (BCLM). However, it remains unclear to what extent tumor regression can be maximized based on modulation of the macrophage phenotype, especially for poorly perfused tumors such as BCLM. Here, for the first time, a CRISPR system is employed to permanently modulate macrophage polarization in a controlled in vitro setting. This enables the design of 3D co-culture experiments mimicking the BCLM hypovascularized environment with various ratios of polarized macrophages. We implement a mathematical framework to evaluate nanoparticle-mediated chemotherapy in conjunction with TAM polarization. The response is predicted to be not linearly dependent on the M1:M2 ratio. To investigate this phenomenon, the response is simulated via the model for a variety of M1:M2 ratios. The modeling indicates that polarization to an all-M1 population may be less effective than a combination of both M1 and M2. Experimental results with the CRISPR system confirm this model-driven hypothesis. Altogether, this study indicates that response to nanoparticle-mediated chemotherapy targeting poorly perfused tumors may benefit from a fine-tuned M1:M2 ratio that maintains both phenotypes in the tumor microenvironment during treatment.