239 The expression of RGR and correlation with proliferation and aberrant differentiation in cutaneous squamous cell carcinomas

Abstract Background: Retinal G protein-coupled receptor (RGR), a photosensitive protein, serves retinal photoisomerase function under light condition in the human eyes. Recently, we found that RGR is highly expressed squamous cell carcinoma (SCC),which suggested photoreceptor may be associated with SCC tumorigenesis. However, cutaneous SCC, expression and of remain uncharacterized. Herein, performed analysis actinic keratosis (AK), Bowen's disease (BD) invasive skin. Objects Methods: In all, 237 samples normal skin (NS, n=28), AK (n=42), BD (n=35) (n=132) were tested for by immunohistochemistry RNAscope methods. Furthermore, evaluated associations clinic-pathological features. Also, PCNA, Ki67 involucrin examined to assess correlation between proliferation or aberrant differentiation using multiimmunofluorescence assays. Results: Invasive contrast NS, BD, had higher protein (p<0.0001). High score was presence increased tumor size, depth, Clark level, classification risk factors, degree as well histologic subtype (p=0.005, p=0.021, p=0.002, p=0.005, p=0.001, respectively). Additionally, inversely correlated (differentiation marker) expression, while it positively Proliferating nuclear antigen (PCNA), suggesting high reduced SCC. Conclusions: significantly tumorigenesis aggressive biology through regulating balance differentiation.