Analysis of proliferation, apoptosis and keratin expression in cultured normal and immortalized human buccal keratinocytes.
The current study was undertaken to analyse growth and differentiation-related functions of normal keratinocytes (NOK) and an SV40T-immortalized keratinocyte line (SVpgC2a) from buccal mucosa, viewing the latter cell line as a model of a dysplastic epithelium. Morphological and immunohistochemical assessments of organotypic epithelia generated from 10 or 17 d of culture showed three- to five-fold higher apoptotic and proliferative activity in SVpgC2a relative to NOK. Conditions with or without serum (up to 10%) did not significantly influence these parameters in NOK whereas serum supported proliferation of SVpgC2a. Both cell types showed basal expression of collagen IV and laminin 1, indicating basal lamina, as well as vimentin, indicating an activated, proliferative state. Reduced expression of keratin, including the non-keratinizing marker K13, was seen in SVpgC2a. Assessment of proliferative monolayer cultures by microarray showed that NOK transcribed tissue-specific keratins, but also the epidermal keratin K2a, several simple epithelial keratins and low levels of hair keratins. SVpgC2a transcribed keratins seen in epithelial dysplasia, and K2a and hair keratins, albeit at low level. Overall, the results implied aberrant apoptosis, proliferation and keratin expression in the immortalized state of SVpgC2a. Comparison of NOK and SVpgC2a under identical culture conditions may serve to model the progression from a normal to a pre-neoplastic state of buccal epithelium.
Hansson
Annette
A
Experimental Carcinogenesis Group, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
Bloor
Balvinder K
BK
Sarang
Zsolt
Z
Haig
Ylva
Y
Morgan
Peter R
PR
Stark
Hans-Jürgen
HJ
Fusenig
Norbert E
NE
Ekstrand
Jan
J
Grafström
Roland C
RC
D017209:Apoptosis; D018929:Cell Culture Techniques; D002454:Cell Differentiation; D002455:Cell Division; D002461:Cell Line, Transformed / Q000502:physiology; D002471:Cell Transformation, Neoplastic / Q000378:metabolism*; D002478:Cells, Cultured; D024141:Collagen Type IV / Q000096:biosynthesis; D016895:Culture Media, Serum-Free; D006801:Humans; D007124:Immunoenzyme Techniques; D015603:Keratinocytes / Q000166:cytology* / Q000378:metabolism*; D007633:Keratins / Q000096:biosynthesis*; D007797:Laminin / Q000096:biosynthesis; D009061:Mouth Mucosa / Q000166:cytology*; D020411:Oligonucleotide Array Sequence Analysis; D009928:Organ Specificity; D012333:RNA, Messenger / Q000032:analysis; D014746:Vimentin / Q000096:biosynthesis
D024141:Collagen Type IV; D016895:Culture Media, Serum-Free; D007797:Laminin; D012333:RNA, Messenger; D014746:Vimentin; C121346:laminin 1; D007633:Keratins