GATA3 acetylation at K119 by CBP inhibits cell migration and invasion in lung adenocarcinoma

GATA3 is a transcriptional factor involved in the development of multiple organs. Post translational modifications of GATA3 are critical to its function. Here, we report that GATA3 interacts with and is acetylated by the acetyltransferase CBP. Class I deacetylases HDAC1, HDAC2 and HDAC3 deacetylate GATA3. The major acetylated site of GATA3 in lung adenocarcinoma cells was determined at lysine 119 (AcK119). Functionally, GATA3-acetylation mimics K119Q mutant was found to inhibit lung adenocarcinoma cell migration and invasion with concomitant downregulation of EMT-controlling transcriptional factors Slug, Zeb1 and Zeb2. Taken together, we demonstrated that GATA3 acetylation at lysine 119 by CBP hinders the migration and invasion of lung adenocarcinoma cells.

Regulation of cyclic adenosine monophosphate response element binding protein on renin expression in kidney via complex cyclic adenosine monophosphate response element-binding-protein-binding protein/P300 recruitment

INTRODUCTION

Renin synthesis and release is the rate-limiting step in the renin-angiotensin system, because cyclic adenosine monophosphate (cAMP) has been identified as dominant pathway for renin gene expression, and cAMP response element-binding protein (CREB) is found in the human and mouse renin promoter. This study aimed to evaluate the role of CREB in expression of the renin gene.

MATERIALS AND METHODS

We created conditional deletion of CREB in mice with low-sodium diet, specifically in renin cells of the kidney. To assess the effect of CREB on renin expression, immunostaining of renin was used in samples from wild-type mice and mice with gene knock-down of CREB. Cyclic AMP response element-binding-protein-binding protein (CBP) and p300 were measured in cultured renin cells of the mice, and RNA detection was done with real-time polymerase chain reaction.

RESULTS

With low-sodium diet, renin was expressed along the whole wall of the afferent glomerular arterioles in wild-type mice, while there was no increase or even decrease in renin expression in CREB-specific deletion mice; RNA level of renin in cultured cells decreased by 50% with single knock-down of CREB, CBP, or p300, and decreased 70% with triple knock-down of CREB, CBP, and p300.

CONCLUSIONS

This study found that CREB was important for renin synthesis and the role of CREB can be achieved through the recruitment of co-activators CBP and p300.

Expression of p300 and CBP is associated with poor prognosis in small cell lung cancer

PURPOSE

To investigate the correlation among p300, CBP and MLL expression and the clinicopathological characteristics in resected SCLC patients.

METHODS

Two hundred and twenty-two resected SCLC patients were included in this study. We evaluated p300, CBP and MLL expression by immunohistochemistry.

RESULTS

Patients with high p300 expression had shorter OS and DFS than those with low p300 expression (p = 0.01; p = 0.009, respectively). The patients with CBP-positive tumors had significantly lower OS and DFS than those with CBP-negative tumors (p = 0.005 and p = 0.007, respectively). Moreover, the p300- and CBP-positive (+) group had a significantly poor OS and DFS. The multivariate Cox regression analysis showed that high p300 and CBP expression are independent markers of poor overall survival (p = 0.006; p = 0.017, respectively) in operable SCLC patients.

CONCLUSIONS

High p300 and CBP expression are independent prognostic markers of poor overall survival for resected SCLC patients. The combination of p300 and CBP expression may be useful in identifying patients with increased risks of cancer recurrence of SCLC.

Nuclear receptor coactivators function in estrogen receptor- and progestin receptor-dependent aspects of sexual behavior in female rats

The ovarian hormones, estradiol (E) and progesterone (P) facilitate the expression of sexual behavior in female rats. E and P mediate many of these behavioral effects by binding to their respective intracellular receptors in specific brain regions. Nuclear receptor coactivators, including Steroid Receptor Coactivator-1 (SRC-1) and CREB Binding Protein (CBP), dramatically enhance ligand-dependent steroid receptor transcriptional activity in vitro. Previously, our lab has shown that SRC-1 and CBP modulate estrogen receptor (ER)-mediated induction of progestin receptor (PR) gene expression in the ventromedial nucleus of the hypothalamus (VMN) and hormone-dependent sexual receptivity in female rats. Female sexual behaviors can be activated by high doses of E alone in ovariectomized rats, and thus are believed to be ER-dependent. However, the full repertoire of female sexual behavior, in particular, proceptive behaviors such as hopping, darting and ear wiggling, are considered to be PR-dependent. In the present experiments, the function of SRC-1 and CBP in distinct ER- (Exp. 1) and PR- (Exp. 2) dependent aspects of female sexual behavior was investigated. In Exp. 1, infusion of antisense oligodeoxynucleotides to SRC-1 and CBP mRNA into the VMN decreased lordosis intensity in rats treated with E alone, suggesting that these coactivators modulate ER-mediated female sexual behavior. In Exp. 2, antisense to SRC-1 and CBP mRNA around the time of P administration reduced PR-dependent ear wiggling and hopping and darting. Taken together, these data suggest that SRC-1 and CBP modulate ER and PR action in brain and influence distinct aspects of hormone-dependent sexual behaviors. These findings support our previous studies and provide further evidence that SRC-1 and CBP function together to regulate ovarian hormone action in behaviorally-relevant brain regions.

ERK1/2 control phosphorylation and protein level of cAMP-responsive element-binding protein: a key role in glucose-mediated pancreatic beta-cell survival

cAMP-responsive element-binding protein (CREB) is required for beta-cell survival by regulating expression of crucial genes such as bcl-2 and IRS-2. Using MIN6 cells and isolated rat pancreatic islets, we investigated the signaling pathway that controls phosphorylation and protein level of CREB. We observed that 10 mmol/l glucose-induced CREB phosphorylation was totally inhibited by the protein kinase A (PKA) inhibitor H89 (2 micromol/l) and reduced by 50% with the extracellular signal-regulated kinase (ERK)1/2 inhibitor PD98059 (20 micromol/l). This indicates that ERK1/2, reported to be located downstream of PKA, participates in the PKA-mediated CREB phosphorylation elicited by glucose. In ERK1/2-downregulated MIN6 cells by siRNA, glucose-stimulated CREB phosphorylation was highly reduced and CREB protein content was decreased by 60%. In MIN6 cells and islets cultured for 24-48 h in optimal glucose concentration (10 mmol/l), which promotes survival, blockade of ERK1/2 activity with PD98059 caused a significant decrease in CREB protein level, whereas CREB mRNA remained unaffected (measured by real-time quantitative PCR). This was associated with loss of bcl-2 mRNA and protein contents, caspase-3 activation, and emergence of ultrastructural apoptotic features detected by electron microscopy. Our results indicate that ERK1 and -2 control the phosphorylation and protein level of CREB and play a key role in glucose-mediated pancreatic beta-cell survival.