# MiRNAs in Interstitial Skin Fluid Sampled with Swellable Hydrogel Microneedles Are Locally Deregulated Near Malignant Skin Lesions in Early Stages of Cutaneous Squamous Cell Carcinoma

## TL;DR

Researchers found that miRNAs in skin fluid near early-stage skin cancer are deregulated, suggesting a new way to detect skin cancer early.

## Contribution

The study introduces a minimally invasive method using hydrogel microneedles to sample miRNAs in skin fluid for early skin cancer detection.

## Key findings

- miRNAs in perilesional skin fluid show greater deregulation compared to blood in mouse models of skin cancer.
- Hydrogel microneedles effectively capture and recover miRNAs from human skin.
- Extracellular skin fluid offers a new opportunity for early diagnosis of skin cancers.

## Abstract

Interrogating molecular
biomarkers in bodily fluids has emerged
as a clinically useful strategy for the early diagnosis of many cancer
types. Interstitial skin fluid is currently being explored as a possible
alternative to blood, containing the same types of biomarkers but
lacking cells and debris that hold little or no clinical value. The
discovery and validation of molecular biomarkers with diagnostic or
prognostic value and the development of clinical tests based on their
detection require minimally invasive technologies capable of sampling
this fluid in a pain-free manner. Biomarkers must also be easily recoverable
for follow-on analysis. Herein, we combine standard genomic approaches
with innovative bioengineering technologies to demonstrate that short
noncoding miRNAs are significantly deregulated in extracellular skin
fluid surrounding malignant skin lesions, providing a yet largely
unexplored window of opportunity for early diagnosis of skin cancers.
Hydrogel-based microneedle patches offering clinically useful sampling
capacity were developed that enable the rapid capture and recovery
of endogenous miRNAs from human skin through deformation of the epidermal–dermal
junction. Using mouse models of cutaneous squamous cell carcinoma,
a significantly greater level of deregulation of selected miRNAs was
observed in perilesional skin fluid compared to that in blood levels.