Developmental patterns of Ki-67, bcl-2 and caspase-3 proteins expression in the human upper jaw.
The distribution of the Ki-67, bcl-2 and caspase-3 proteins was immunohistochemically analyzed in the developing human upper jaw (5th-10th gestational weeks). During this period, proliferative activity gradually decreased from higher levels at the earliest stages (50-52%) to lower levels, both in the jaw ectomesenchyme and in the epithelium. The highest expression of bcl-2 protein was found in the epithelium and ectomesenchyme of areas displaying lower rates of cell proliferation. High levels of caspase-3 protein were detected during the earliest stages of jaw development, indicating an important role for apoptosis in morphogenesis of early derivatives of the maxillary prominences. The number of Ki-67, bcl-2 and caspase-3 positive cells changed in a temporally and spatially restricted manner, coincidently with upper jaw differentiation. While apoptosis might control cell number, bcl-2 could act in suppression of apoptosis and enhancement of cell differentiation. A fine balance between cell proliferation (Ki-67), death (caspase-3) and cell survival (bcl-2) characterized early human upper jaw development. A rise in the number of apoptotic cells always temporally coincided with the decrease in number of surviving bcl-2 positive cells within the palatal region. Therefore, the upper jaw development seems to be controlled by the precisely defined expression of genes for proliferation, apoptosis and cell survival.
Novakovic
Josip
J
Department of Anatomy, Histology and Embryology, School of Medicine, University of Mostar, Bosnia and Herzegovina.
Mardesic-Brakus
Snjezana
S
Vukojevic
Katarina
K
Saraga-Babic
Mirna
M
D017209:Apoptosis; D053148:Caspase 3 / Q000378:metabolism*; D002454:Cell Differentiation; D049109:Cell Proliferation; D004848:Epithelium / Q000196:embryology / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism*; D008437:Maxilla / Q000166:cytology / Q000196:embryology* / Q000502:physiology; D008648:Mesoderm / Q000196:embryology / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*
D019394:Ki-67 Antigen; D019253:Proto-Oncogene Proteins c-bcl-2; C505407:CASP3 protein, human; D053148:Caspase 3