The studies of roles and mechanism of primary cilium in the progressing of multiple osteochondromas

Abstract

Objective To explore the pathological role of primary cilium in multiple osteochondromas by comparing the difference of primary cilium in the chondrocytes between multiple osteochondromas cartilage cap (MOCC)and normal epiphyseal growth plate cartilage (NEGPC). Methods Chondrocytes lines from MOCC and NEGPC were collected and cultured in vitro. The morphology and incidence of primary cilla in the MOCC and NEGPC were studied by laser confocal scanning microscope, Toluidine blue staining and Sulforhodamine B (SRB) was applied to display different cell morphology and growth rates between MOCC and NEGPC, and alcian blue and alkaline phosphatase (ALP) in MOCC and NEGPC were measured by histochemical staining. Results MOCC and NEGPC cultured in vitro were polygonal or fusiform and were stained with purple particles by toluidine blue staining. The incidence of primary cilla in MOCC [(25.265±1.766)%] was lower than in NEGPC [(53.943±3.631)%], the difference was significant (F=232.692, P=0.000). A values in MOCC were significantly lower than in NEGPC, while both of them were tended to increase with time. Alcian blue staining in MOCC were decreased compared to NEGPC. The area of ALP staining (7.387±2.045) mm2 in MOCC were decreased obviously compared with NEGPC (14.768±2.072) mm2, the difference was significant (F=16.835, P=0.020). Conclusion The primary cilium in chondrocyte was closely related to MO. When the expression of primary cilium in chondrocytes was suppressed, the proliferation, maturation and synthetic function of chondrocytes were delayed in epiphyseal growth plate cartilage. Key words: Multiple osteochondromas; Chondrocytes; Primary cilium; Cell culture