Cyclooxygenase-2 promotes cell proliferation, migration and invasion in U2OS human osteosarcoma cells

Osteosarcoma is the most common primary bone tumor, but the pathogenesis is not well understood. While cyclooxygeanse-2 (COX-2) is known to be closely associated with tumor growth and metastasis in several kinds of human tumors, the function of COX-2 in osteosarcoma is unclear. Therefore, to investigate the function of COX-2 in osteosarcoma, we established stable cell lines overexpressing COX-2 in U2OS human osteosarcoma cells. COX-2 overexpression as well as prostaglandin E(2) treatment promoted proliferation of U2OS cells. In addition, COX-2 overexpression enhanced mobility and invasiveness of U2OS cells, which was accompanied by increases of matrix metalloproteinase-2 and -9 (MMP-2 and -9) activities. Selective COX-2 inhibitors, NS-398 and celecoxib, inhibited cell proliferation and abrogated the enhanced mobility, invasiveness and MMP activities induced by COX-2 overexpression. These results suggest that COX-2 is directly associated with cell proliferation, migration and invasion in human osteosarcoma cells, and the therapeutic value of COX-2 inhibitors should be evaluated continuously.

Indirect measurement of blood pressure in neonates using an automatic noninvasive oscillometric monitor

The measurement of blood pressure in neonates is an important diagnostic procedure. But the measurement of blood pressure has not been performed routinely because of difficulty in measuring blood pressure and variable normal range according to measuring apparatus. Recently some accurate and convenient apparatus of measuring blood pressure have been introduced in neonatal care, so the reference values of neonatal blood pressure may be obtainable. The authors measured systolic and diastolic blood pressure using a noninvasive oscillometric monitor instrument on 1,3,6,12,24,48,72 hours of life in 200 neonates born at Eulji General Hospital, Taejon. And we analysed the results according to birth weight, gestational age, delivery type, sex, meconium stain, preeclampsia and hypocalcemia. The following results were obtained: 1) On the 1st day of life, systolic and diastolic blood pressure were 65.611.7 mmHg and 36.7+/-5.8 mmHg in the normal birth weight neonates, and 56.2+/-6.7 mmHg and 34.14.2 mmHg in the low birth weight neonates, respectively. So the blood pressure of normal birth weight neonates were higher than that of low birth weight neonates. 2) On the 1st day of life, systolic and diastolic blood pressure were 65.5+/-11.8 mmHg and 36.6+/-5.8 mmHg in the fullterm neonates, and 57.6+/-5.2 mmHg and 35.6+/-3.8 mmHg in the preterm neonates, respectively. So the blood pressure of full term neonates were higher than that of preterm neonates. 3) The difference of blood pressure in analysis according to birth weight were wider than that according to gestational age. 4) The blood pressure of neonates were lowest on the 3 hours of life and increased gradually during 72 hours of life. 5) The blood pressure of neonates did not show any significant difference in analysis according to sex. delivery type, Meconium stain, preeclampsia, and hypocalcemia.