2025-07-28 ミシガン大学
The silicone patch for at-home melanoma testing has star-shaped microneedles, just 0.6 millimeters long, that press into skin without drawing blood. A gel that coats the needles attracts exosomes that come from cancerous cells. Image credit: Jeremy Little, Michigan Engineering.
<関連情報>
- https://news.umich.edu/at-home-melanoma-testing-with-skin-patch-test/
- https://www.sciencedirect.com/science/article/abs/pii/S0956566325004348
星型シリコンマイクロニードルを用いた迅速なポイントオブケアメラノーマエクソソームの分離と検出(ラテラルフローアッセイによる) Stellate silicon microneedles for rapid point-of-care melanoma exosome isolation and detection via a lateral flow assay
Scott M. Smith, Abha Kumari, Joseph P. Marvar, Nna-Emeka Onukwugha, Yoon-Tae Kang, Sunitha Nagrath
Biosensors and Bioelectronics Available online 16 May 2025
DOI:https://doi.org/10.1016/j.bios.2025.117560
Abstract
Melanoma is the most aggressive type of skin cancer with high mortality rates. Early diagnosis is crucial because it significantly improves treatment outcomes, but conventional methods relying on dermoscopy and lesion biopsy have limitations in accuracy during early stages and are invasive. Liquid biopsies offer a minimally invasive alternative, particularly for routine screening. The abundance of cancer cell-driven extracellular vesicles in interstitial fluid can be utilized for point-of-care cancer diagnostics. Here, we developed a stellate silicon microneedle patch, the ExoPatch, coated with Annexin V functionalized hydrogel to isolate melanoma-specific exosomes. The ExoPatch captures exosomes directly from the skin, followed by dissolution of the hydrogel to release the exosomes, which are then detected using a lateral flow immunoassay specific to melanoma markers (MCAM and MCSP). After validating with cell line derived extracellular vesicles and testing with mouse tissue, the ExoPatch isolated 11.5 times more protein from melanoma tissue compared to healthy tissue. Additionally, the ExoPatch effectively distinguished between melanoma and healthy tissues, with its specificity confirmed through Western Blot and electron microscopy analysis. The ExoPatch with melanoma mouse samples produced a 3.5-fold higher signal in the lateral flow immunoassay compared to that of healthy controls. The ExoPatch presents a promising point-of-care diagnostic tool for melanoma, offering significant advantages in terms of rapidness, minimal invasiveness, and ease of use. It has the potential to enhance early detection and routine monitoring in melanoma patients, ultimately improving patient outcomes by reducing the reliance on traditional, invasive biopsies.
