PubMed Health⌕ Search

Biomedical subjects

J Luker

Publications and source records attributed to J Luker.

32 records · Page 2Linked to original sources
PubMed1988

The expression of MHC antigens on cultured oral keratinocytes and relationship to malignancy.

Major histocompatibility complex (MHC) antigen expression has been postulated to have an important role in host defences against tumour development. In this study the expression of MHC class I and class II antigens in vitro, both constitutive and in response to interferon gamma (IFN gamma), was examined in a series of cell lines established from a rat model of oral carcinogenesis. Constitutive expression of MHC class I and class II antigens was not related to the degree of malignancy of the cell lines, as reflected by their anchorage independence in agarose gels and their capacity to form tumours in athymic mice. MHC class I response to IFN gamma stimulation did not correlate with tumorigenicity, but the MHC class II response was significantly decreased in one of the four tumorigenic cell lines. The results show that the expression of MHC antigens in response to IFN gamma varied between different keratinocyte cell lines but did not consistently reflect the tumorigenic phenotype.

Animals↗
PubMed1986

Characterization of malignant rat keratinocytes in culture following the induction of oral squamous cell carcinomas in vivo.

An in vivo model of oral epithelial carcinogenesis in rats has been established successfully in cell culture. Oral carcinomas of the tongue and palate were induced in Sprague-Dawley male rats by painting their palates three times weekly for 7-8 months with 0.5% (w/v) 4-nitroquinoline-N-oxide. Oral keratinocytes from malignant and untreated control tissues were cultivated using 3T3 fibroblast support. Both the normal and malignant cells stained positively with an anti-human keratin polyclonal antibody but malignant keratinocytes were heterogeneous with regard to cell size, shape and intercellular packing, unlike the regular organization of the normal cultures. Malignant keratinocyte cultures differed markedly from their normal counterparts by an increase in their growth rate, the capacity for serial cultivation to the 25th passage (to date) and independence of 3T3 fibroblast support. In contrast, cultures established from healthy tissue showed signs of senescence usually by passage 4 and were totally reliant on 3T3 fibroblast support for growth. Malignant keratinocytes expressed anchorage independence when cultured in a semi-solid medium and gave rise to tumour formation in athymic mice. The development of this specialized cell culture system substantially increases the potential of the rat 4NQO model to investigate the pathogenesis of oral squamous cell carcinomas.

Animals↗