Sox9 expression in canine epithelial skin tumors

Abstract

Sox9 is a master regulatory gene involved in developmental processes, stem cells maintenance and tumorigenesis. This gene is expressed in healthy skin but even in several skin neoplasms, where its expression patterns often resembles those of the developing hair follicle. In this study, samples from eleven different types of canine skin neoplasms (squamous papilloma, squamous cell carcinoma, infundibular keratinizing acanthoma, inferior tricholemmoma, isthmic tricholemmoma, trichoblastoma, trichoepithelioma, malignant trichoepithelioma, pilomatricoma, subungual keratoacanthoma, subungual squamous cell carcinoma) were immunohistochemically stained and evaluated for Sox9 with the aim to correlate tumor phenotype with molecular characteristics that may help to better define tumor development, contribute to its diagnosis and clinical management. Keratoacanthoma excluded, all the skin neoplasms examined showed a variable positivity to Sox9, especially in the basal layers, but with major intensity in neoplasms developing from the bulge region of the hair follicle, as trichoblastoma. According to our results, Sox9 could be employed as a stem cell marker to better assess the role of stem cells in canine epidermal and follicular tumors.

Canine Epithelial Skin Tumours: Expression of the Stem Cell Markers Lgr5, Lgr6 and Sox9 in Light of New Cancer Stem Cell Theories

“…The immunohistochemical expression pattern of Sox9 in canine normal HFs, as already previously reported by Gerhards et al [ 11 ], would confirm it as a marker of stem cells already committed to ORS differentiation, as in human HFs [ 29 ]. We observed a Sox9-positive cell subpopulation in both epidermal and HF tumours, confirming results reported by Fantinato et al [ 17 ]. Our results would indicate, in some canine HF tumours, such as IKA, TE and TB, as well as in SCC and BCC, the presence of ORS differentiation and/or a potential role of these cells in the development of these tumour types.…”

“…These findings suggest a potential implication of these molecules in the development, maintenance and/or progression of canine skin tumours. A few other published studies focused on the examination of selected putative stem cell markers to better classify canine cutaneous epithelial tumours and their cell of origin [ 17 , 18 ]. However, the exact role of these cells as TICs in canine skin tumour development and progression is not understood.…”

Histologic features of hair follicle neoplasms and cysts in dogs and cats: a diagnostic guide

“…4 SOX9 is reported to be expressed in variable levels in all HF tumors, but was expressed most strongly in trichoblastomas. 14…”

Is there still room for novelty, in histochemical papers?

“…In most of the published papers on Tumor biology & markers , 4-21 the expression of specific protein has been investigated (in hepatocellular carcinoma, 4-6 uterine lesions, 7,8 colorectal carcinoma, 9,10 and other neoplasms 11,15,21 ). The aim was either to originally define new diagnostic/prognostic markers, 4,6,8,10-12 or to identify proteins involved in tumor onset 7 or progression, 5,21 or to evaluate the effect of therapy.…”