Increased epithelial cell proliferation in nasal polyps.
OBJECTIVE
To detect, quantify, and compare respiratory epithelial cell proliferation in nasal mucosa and polyps from patients with nasal polyposis.


METHODS
Cohort study.


METHODS
Patients and samples were selected at the Hôpital Intercommunal de Créteil (France). Flow cytofluorometry and immunohistochemistry were performed at Hôpitaux Tenon and Mondor (Université Paris [France] VI et XII).


METHODS
Twenty-one patients undergoing endoscopic ethmoidectomy for treatment of nasal polyposis.


METHODS
In 10 cases, epithelial cells were removed from frozen inferior turbinate mucosa and polyps by mechanical disaggregation and were then analyzed by flow cytofluorometry, providing the cell DNA content (propidium iodide labeling) and the percentage of S-phase cells. In 11 cases, inferior turbinate mucosa and polyps were fixed in formaldehyde and embedded in paraffin. Proliferating cell nuclear antigen expression in the epithelium was quantified by immunohistochemistry; a proliferating cell nuclear antigen index was calculated for each sample in the basal area, suprabasal area, and full height of the epithelium.


RESULTS
All cell populations studied were diploid, and percentages of S-phrase cells were significantly higher in nasal polyps than in mucosa. Proliferating cell nuclear antigen indexes were significantly higher in nasal polyps than in the suprabasal area and full height of the mucosal epithelium.


CONCLUSIONS
Cell proliferation is increased in epithelium from nasal polyps. Epithelial damage caused by inflammatory mediators could induce this increased cell proliferation via epithelial repair processes. Inflammatory cells could up-regulate epithelial cell proliferation by secreting growth factors.
Coste
A
A
Department of Oto-Rhino-Laryngology and Head and Neck Surgery, Henri Mondor and Interncommunal University Hospitals, University of Paris XII, Creteil, France.
Rateau
J G
JG
Roudot-Thoraval
F
F
Chapelin
C
C
Gilain
L
L
Poron
F
F
Peynegre
R
R
Bernaudin
J F
JF
Escudier
E
E
D002455:Cell Division; D002467:Cell Nucleus / Q000737:chemistry; D015331:Cohort Studies; D004247:DNA / Q000032:analysis; D004171:Diploidy; D004848:Epithelium / Q000254:growth & development; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D008940:Mitotic Index; D009297:Nasal Mucosa / Q000473:pathology*; D009298:Nasal Polyps / Q000473:pathology*; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D016196:S Phase
D018809:Proliferating Cell Nuclear Antigen; D004247:DNA