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.

Case of an Intracystic (Encysted) Papillary Carcinoma of the Breast

Intracystic (encysted) papillary carcinoma of the breast (IPC) is a rare tumor with predilection for elderly postmenopausal women and has distinctive pathological features that should be distinguished from those of ductal carcinoma in situ (DCIS) of the papillary type and invasive papillary carcinoma. IPC can appear in a pure form or can be associated with DCIS or invasive carcinoma. It is usually a low-grade carcinoma with overall good prognosis, presenting low or intermediate nuclear grade, no necrosis, high positivity to estrogen receptors, and the negativity for c-erbB-2. We report here a case of IPC managed by lumpectomy with ipsilateral axillary lymph node dissection