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The effectiveness of methods to prevent stroke recurrence and of education focusing on learners' needs has not been fully explored. The aims of this study were to assess the effects of such interventions among stroke patients and their primary caregivers and to evaluate the feasibility of a web-based stroke education program. The participants were 36 patients with a clinical diagnosis of ischemic stroke within 12 months post-stroke and their primary caregivers. The participants were randomly assigned to either an experimental or a control group. The primary measures included blood chemistry, self-reported health behaviors, sense of control, and health motivation for stroke patients, and caregiver mastery for caregivers. To test the feasibility of the intervention program, the rates of participation and occurrence of technical problems were calculated. The experimental group tended to improve significantly more than the control group in terms of exercise, diet, sense of control and health motivation for the stroke patients and in terms of caregiver mastery for the primary caregivers. The rate of participation in the web-based program was 63.1%. This program, which focuses on recurrence prevention in stroke patients and caregivers, has the potential to improve health behaviors for stroke patients.

Introduction: Hyperprogressive disease (HPD), characterized by accelerated tumor progression, has been proposed as a new pattern of progression after immune checkpoint inhibitor (ICI) treatment. The aim of this study was to describe the characteristics of HPD and investigate its predictive markers. Methods: Clinical and radiological findings of 335 patients with advanced NSCLC treated with ICI monotherapy were retrospectively analyzed. Radiological data were quantitatively and longitudinally analyzed for tumor size and volume by comparing baseline and follow-up computerized tomography results. The findings were matched with individual genomic profiles generated by deep sequencing of 380 genes.

The hepatitis B virus (HBV) X protein (pX) is impli-Patients chronically infected with hepatitis B virus develop hepatocellular carcinoma (HCC) 1 in their 4th or 5th decade (1). The 16.5-kDa X protein, encoded by HBV, is implicated in HCC pathogenesis (2). Despite numerous studies describing pX activities, the molecular mechanism by which pX affects hepatocyte transformation is unknown. This study addresses aspects of the pX-mediated mechanism of hepatocyte transformation.It is well accepted that pX is a multifunctional protein affecting transcription (2, 3), cell growth (4, 5), and apoptosis (6 -8). Although not DNA binding, pX is a promiscuous transactivator of diverse cis-acting elements, including AP-1 (9 -12), NF-B (13-15), AP-2 (11), and CRE (16 -18) sites. This transcriptional promiscuity of pX is understood to be due to its dual mechanism of action (19). pX interacts directly with specific components of the basal transcriptional apparatus (20 -24) and with bZip (CREB/ATF) transcription factors (16 -18), resulting in enhanced CRE/bZip-mediated transcription (16,18). In addition to affecting direct transcriptional induction, pX activates the RAS-RAF-MAPK (19, 25) and JNK (26) pathways, resulting in enhanced transcription from AP-1 and NF-B cis-acting elements.pX-mediated activation of the RAS-RAF-MAPK pathway has been linked to accelerated entry of cells into S phase (4); however, the significance of the pX-dependent activation of this mitogenic pathway in hepatocyte transformation has not been demonstrated directly. Furthermore, the significance of the pX-dependent activation of the JNK pathway also remains unclear, since JNK pathway activation in some cases has been linked to transformation (27-29) and in other cases to apoptosis (30 -33).To understand the significance of pX-induced reprogramming of the mitogenic process in hepatocyte transformation, we employed a new cellular model, composed of immortalized hepatocytes, AML12 cells (34), expressing pX via the tetracycline-regulated expression system (35). We have characterized two hepatocyte lineages derived from AML12 cells as follows: 1) a differentiated hepatocyte (3pX-1) cell line, similar to the parental AML12 cells, and 2) a de-differentiated hepatocyte (4pX-1) cell line. We have demonstrated that conditional expression of pX leads to transformation in the differentiated 3pX-1 hepatocyte cell line; by contrast, expression of pX in the de-differentiated 4pX-1 cell line does not lead to transformation (35). Importantly, our observations agree with clinical data reporting the majority of HCC is derived from differentiated hepatocytes (36) versus the progenitor "oval cells." Thus, our cellular model system is ideal for investigating physiologically relevant, early signaling events activated by pX during hepatocyte transformation, and for comparing these to signaling events occurring in a cellular environment refractory to pXmediated cellular transformation.Herein, we characterize the mitogenic status of the 3pX-1 and 4pX-1 cell lines affected by pX, t...

Hepatitis B virus (HBV) X protein (pX) is implicated in Epidemiological evidence (1) links chronic hepatitis B virus (HBV)1 infection in humans to development of hepatocellular carcinoma (HCC). Evidence derived from comparative studies of mammalian and avian hepadnaviruses, transgenic animal studies, and cell culture transformation studies collectively (2, 3) support a role for the 16.5-kDa HBV X protein (pX) as a weak oncogene, implicated in HCC development. However, the mechanism(s) by which pX effects hepatocyte transformation is not yet understood. Also not entirely understood is the cell type in the liver, which is the precancerous precursor giving rise to HBV-mediated HCC. The accumulating evidence derived from rat models of hepatocarcinogenesis (4 -7), woodchuck hepatitis virus-mediated HCC (8), and human liver pathologies (9, 10) point to the undifferentiated (oval cell) or less-differentiated (transitional) hepatocyte as the precancerous precursor in HCC development.Activities ascribed to pX probably linked to HBV-mediated pathology include activation of the Ras-Raf-MAPK (11-14), JNK (15), and STAT3 pathways (16, 17); direct interactions with specific components of the basal transcriptional apparatus (18 -21) and with the CREB/ATF family of transcription factors (22-25); interaction with DNA repair proteins (26); and activation of the proteasome complex (27). Importantly, many studies have demonstrated that pX expression in different cell types (Chang cells, NIH3T3 cells, immortalized differentiated AML12 hepatocytes) results in distinct and opposing cellular responses, including cell cycle progression (28), G 1 /S phase arrest (29, 30), transformation (31, 32), and apoptosis (32-35). However, despite evidence supporting the growth-promoting (36) versus the antiproliferative or apoptotic function of pX (37), the molecular mechanisms by which pX effects these processes, for the most part, remain to be deciphered. Likewise, the significance of these pX-mediated processes in HCC development is poorly understood.In our studies, we employ a cellular model system linked to pX-mediated hepatocyte transformation (32) and suitable to molecular analyses. It is composed of two tetracycline-regulated, pX-expressing cell lines, a differentiated hepatocyte 3pX-1 cell line, and a dedifferentiated hepatocyte 4pX-1 cell line. Conditional pX expression selectively transforms the 3pX-1 cell line. We recently demonstrated (36) that an early pX-mediated event in 3pX-1 cells is sustained activation of the Ras-Raf-MAPK pathway, an activation that is causally linked to pX-mediated transformation. In the pX-nontransforming 4pX-1 cell line, pX expression results in sustained activation of the JNK pathway and only transient activation of the Ras-Raf-MAPK pathway. Since pX expression mediates distinct growth characteristics between the 3pX-1 and 4pX-1 cell lines (i.e. transformation in the differentiated 3pX-1 cells versus absence of transformation in the less differentiated 4pX-1 cells and differential activation of the Ras-Raf-M...

The bZIP transcription factor C/EBP␤ is a target of Ras signaling that has been implicated in Ras-induced transformation and oncogene-induced senescence (OIS). To gain insights into Ras-C/EBP␤ signaling, we investigated C/EBP␤ activation by oncogenic Ras. We show that C/EBP␤ DNA binding is autorepressed and becomes activated by the Ras-Raf-MEK-ERK-p90 RSK cascade. Inducible phosphorylation by RSK on Ser273 in the leucine zipper was required for DNA binding. In addition, three other modifications (phosphorylation on Tyr109 [p-Tyr109], p-Ser111, and monomethylation of Arg114 [me-Arg114]) within an N-terminal autoinhibitory domain were important for Ras-induced C/EBP␤ activation and cytostatic activity. Apart from its role in DNA binding, Ser273 phosphorylation also creates an interhelical g7e salt bridge with Lys268 that increases attractive electrostatic interactions between paired leucine zippers and promotes homodimerization. Mutating Ser273 to Ala or Lys268 to Glu decreased C/EBP␤ homodimer formation, whereas heterodimerization with C/EBP␥ was relatively unaffected. The S273A substitution also reduced the antiproliferative activity of C/EBP␤ in Ras V12 -expressing fibroblasts and decreased binding to target cell cycle genes, while a phosphomimetic substitution (S273D) maintained growth arrest function. Our findings identify four novel C/EBP␤-activating modifications, including RSK-mediated phosphorylation of a bifunctional residue in the leucine zipper that regulates DNA binding and homodimerization and thereby promotes cell cycle arrest.

C/EBPβ is an auto‐repressed protein that becomes post‐translationally activated by Ras‐MEK‐ERK signalling. C/EBPβ is required for oncogene‐induced senescence (OIS) of primary fibroblasts, but also displays pro‐oncogenic functions in many tumour cells. Here, we show that C/EBPβ activation by H‐RasV12 is suppressed in immortalized/transformed cells, but not in primary cells, by its 3′ untranslated region (3′UTR). 3′UTR sequences inhibited Ras‐induced cytostatic activity of C/EBPβ, DNA binding, transactivation, phosphorylation, and homodimerization, without significantly affecting protein expression. The 3′UTR suppressed induction of senescence‐associated C/EBPβ target genes, while promoting expression of genes linked to cancers and TGFβ signalling. An AU‐rich element (ARE) and its cognate RNA‐binding protein, HuR, were required for 3′UTR inhibition. These components also excluded the Cebpb mRNA from a perinuclear cytoplasmic region that contains activated ERK1/2, indicating that the site of C/EBPβ translation controls de‐repression by Ras signalling. Notably, 3′UTR inhibition and Cebpb mRNA compartmentalization were absent in primary fibroblasts, allowing Ras‐induced C/EBPβ activation and OIS to proceed. Our findings reveal a novel mechanism whereby non‐coding mRNA sequences selectively regulate C/EBPβ activity and suppress its anti‐oncogenic functions.

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