Granulocyte macrophage-colony stimulating factor and keratinocyte growth factor control of early stages of differentiation of oral epithelium.

Oral epithelial differentiation is known to be directed by underlying fibroblasts, but the responsible factor(s) have not been identified. We aimed here to identify fibroblast-derived factors responsible for oral epithelial differentiation. Primary normal human oral keratinocytes and fibroblasts were isolated from healthy volunteers after informed consent (n = 5) and 3D-organotypic (3D-OT) cultures were constructed.

Identification of two distinct carcinoma-associated fibroblast subtypes with differential tumor-promoting abilities in oral squamous cell carcinoma.

Heterogeneity of carcinoma-associated fibroblasts (CAF) has long been recognized, but the functional significance remains poorly understood. Here, we report the distinction of two CAF subtypes in oral squamous cell carcinoma (OSCC) that have differential tumor-promoting capability, one with a transcriptome and secretome closer to normal fibroblasts (CAF-N) and the other with a more divergent expression pattern (CAF-D). Both subtypes supported higher tumor incidence in nonobese diabetic/severe combined immunodeficient (NOD/SCID) Ilγ2(null) mice and deeper invasion of malignant keratinocytes than normal or dysplasia-associated fibroblasts, but CAF-N was more efficient than CAF-D in enhancing tumor incidence.

Cancer progression is associated with increased expression of basement membrane proteins in three-dimensional in vitro models of human oral cancer.

Background: Although basement membrane was traditionally considered an inert barrier that tumour cells had to cross before invasion into the surrounding stroma, recent studies suggest that basement membrane components are not only degraded during tumour progression, but also newly synthesised at the invasive front.

Objective: This study aimed at evaluating (1) the expression of basement membrane proteins in human oral carcinogenesis and (2) the role that epithelial-mesenchymal interactions play on it, by using an in vitro oral cancer progression model.

Material And Methods: In vitro three-dimensional (3D) organotypic cultures of normal, early neoplastic and neoplastic human oral mucosa were developed by growing primary normal human oral keratinocytes, dysplastic human oral keratinocytes (DOK cell line), and neoplastic human oral keratinocytes (PE/CA-PJ15 cell line) on type I collagen biomatrices, with or without primary fibroblasts isolated from normal human oral mucosa.