The Activation of ERK1/2 Via Tyrosine Kinase Pathway Attenuates TRAIL-induced Apoptosis in HeLa cell / 체질인류학회지

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) serves as an extracellular signal triggering apoptosis in tumor cells. To characterize the molecular events involved in TRAIL-induced apoptotic signaling, we investigated the role of extracellular signal-regulated kinase 1/2(ERK1/2) in the apoptosis using HeLa cells. Here we show that TRAIL pronounced ERK1/2 activation through a tyrosine kinase-dependent mechanism, subsequently elevated anti-apoptotic Bcl-2 protein levels. Pretreatment with Genistein, an inhibitor of tyrosine kinase, significantly attenuated ERK1/2 activation and enhanced cell death. Moreover, inhibition of ERK1/2 with PD98059 promoted apoptotic cell death through the down-regulation of ERK1/2 activity and Bcl-2 protein levels. Taken together, our results suggest that the activation of ERK1/2 via tyrosine kinase pathway plays a protective role as the mechanism of cellular defense through the up-regulation of Bcl-2 protein levels in TRAIL-induced apoptosis.

Relationship between normal heart size and body indices in Korean

We provided a curve-fit equation to predict the normal heart weight (g) in Koreans by examining 422 autopsies (215 males and 207 females, from newborn to age 77 yr) who were relatively in good general condition. Heart weight was well correlated with body surface area (m2), body weight (kg), and body height (cm) but poorly with age in both sex. Heart weight progressively increased from birth to the earlier 3rd and 4th decades in male and female, respectively, and then gradually decreased; mean heart weight of all age group was greater in male than in female and significantly different from birth to 4th decade. In both sex, heart weight exponentially increased in accordance with the increase of body height, body weight, and body surface (in male, heart weight=0.00312 x body height(2.239), r2=0.750, p<0.0001; in female, heart weight=0.00443 x body height(2170), r2=0.781, p<0.0001; in male, heart weight=9.22 x body weight(0.853), r2=0.770, p<0.0001; in female, heart weight=9.00 x body weight0.855, r2=0.820, p<0.0001; in male, heart weight=155.18 x body surface area1.290, r=0.808, p<0.0001; in female, heart weight=124.13 x body surface area1.242, r=0.834, p<0.0001). These results indicate that heart weight is better correlated with body surface area than with body weight; however, body weight should be a better determinant of a predicted heart weight, since body surface area is entirely dependent on body height and body weight.