ELL Protein-associated Factor 2 (EAF2) Inhibits Transforming Growth Factor β Signaling through a Direct Interaction with Smad3

Mechanism of ELL-associated factor 2 and vasohibin 1 regulating invasion, migration, and angiogenesis in colorectal cancer

BACKGROUND

As a novel endogenous anti-angiogenic molecule, vasohibin 1 (VASH1) is not only expressed in tumor stroma, but also in tumor tissue. Moreover, studies have shown that VASH1 may be a prognostic marker in colorectal cancer (CRC). Knockdown of VASH1 enhanced transforming growth factor-β1 (TGF-β1)/Smad3 pathway activity and type I/III collagen production. Our previous findings suggest that ELL-associated factor 2 (EAF2) may play a tumor suppressor and protective role in the development and progression of CRC by regulating signal transducer and activator of transcription 3 (STAT3)/TGF-β1 signaling pathway. However, the functional role and mechanism of VASH1-mediated TGF-β1 related pathway in CRC has not been elucidated.

AIM

To investigate the expression of VASH1 in CRC and its correlation with the expression of EAF2. Furthermore, we studied the functional role and mechanism of VASH1 involved in the regulation and protection of EAF2 in CRC cells in vitro.

METHODS

We collected colorectal adenocarcinoma and corresponding adjacent tissues to investigate the clinical expression of EAF2 protein and VASH1 protein in patients with advanced CRC. Following, we investigated the effect and mechanism of EAF2 and VASH1 on the invasion, migration and angiogenesis of CRC cells in vitro using plasmid transfection.

RESULTS

Our findings indicated that EAF2 was down-regulated and VASH1 was up-regulated in advanced CRC tissue compared to normal colorectal tissue. Kaplan-Meier survival analysis showed that the higher EAF2 Level group and the lower VASH1 Level group had a higher survival rate. Overexpression of EAF2 might inhibit the activity of STAT3/TGF-β1 pathway by up-regulating the expression of VASH1, and then weaken the invasion, migration and angiogenesis of CRC cells.

CONCLUSION

This study suggests that EAF2 and VASH1 may serve as new diagnostic and prognostic markers for CRC, and provide a clinical basis for exploring new biomarkers for CRC. This study complements the mechanism of EAF2 in CRC cells, enriches the role and mechanism of CRC cell-derived VASH1, and provides a new possible subtype of CRC as a therapeutic target of STAT3/TGF-β1 pathway.

Overexpression of ELL-associated factor 2 suppresses invasion, migration, and angiogenesis in colorectal cancer

BACKGROUND

The androgen responsive gene, ELL-associated factor 2 (EAF2), expressed in benign prostate tissues, has been shown to play an important role in tumor suppression in a variety of malignant tumors. In addition, some scholars found that EAF2 frameshift mutations are associated with intratumor heterogeneity in colorectal cancer (CRC) and inactivation of EAF2 in microsatellite instability-high CRC. However, the molecular mechanism by which EAF2 is involved in CRC invasion and metastasis remains unclear.

AIM

To determine the clinical value of expression of EAF2 protein in CRC, and to study the effects of EAF2 on the invasion, migration, and angiogenesis of CRC cells in vitro.

METHODS

In this study, we collected colorectal adenocarcinoma and corresponding adjacent tissues to investigate the clinical expression of EAF2 protein in patients with advanced CRC. Subsequently, we investigated the effect of EAF2 on the invasion, migration, and angiogenesis of CRC cells in vitro using plasmid transfection.

RESULTS

EAF2 protein was lowly expressed in cancer tissues of patients with advanced CRC. Kaplan-Meier survival analysis showed that the survival rate of the high EAF2 level group was higher than that of the low EAF2 level group.

CONCLUSION

Our results demonstrated that EAF2, as a tumor suppressor, may inhibit the invasion, metastasis, and angiogenesis of CRC cells by regulating the signal transducer and activator of transcription 3/transforming growth factor-β1 crosstalk pathway, and play a cancer suppressive and protective role in the occurrence and development of CRC. Our findings are of great significance to provide a new idea and theoretical basis for the targeted diagnosis and treatment of CRC.

Human kallikrein overexpression alleviates cardiac aging by alternatively regulating macrophage polarization in aged rats

Cardiac aging is characterized by myocardial hypertrophy, fibrosis, and diastolic dysfunction. Human kallikrein (hKLK1) protects against fibrosis in various pathogenic states. However, the effects of hKLK1 overexpression on cardiac aging-related fibrosis and the underlying mechanisms remain unknown. Moreover, the role of hKLK1 in regulating macrophage function leading to cardiac fibrosis has not been investigated. Thus, in this study, we determined the effects of hKLK1 on cardiac aging and explored the mechanisms through which hKLK1 regulated aging-related fibrosis. Echocardiographic measurements showed that aging caused significant alternations in cardiac morphology, hypertrophy, and fibrosis in rats, and hKLK1 overexpression protected against aging-induced cardiac dysfunction. Compared with wild-type hearts, the hKLK1 transgene decreased the expression of monocyte chemoattractant protein 1 and suppressed mitochondrial dysfunction and excess oxidative stress, leading to decreased recruitment and retention of alternatively activated (M2) macrophages and reduced secretion of profibrotic cytokines mediated by the TGF-β1-Smad3 signaling pathway in hearts of aging rats. Furthermore, these cardioprotective effects of hKLK1 overexpression were associated with the Janus kinase-signal transducer and activator of transcription 3 signaling pathway. H₂O₂-induced senescence promoted the differentiation of RAW264.7 cells into M2-type cells induced by IL-4 treatment. Bradykinin treatment relieved the migratory capacity of macrophages induced by H₂O₂. Thus, hKLK1 overexpression reduced cardiac fibrosis and improved aging-related cardiac dysfunction through reduced shift of macrophages to M2 macrophages, indicating that hKLK1 may alleviate aging-related cardiac dysfunction.-Hu, D., Dong, R., Yang, Y., Chen, Z., Tang, Y., Fu, M., Wang, D. W., Xu, X., Tu, L. Human kallikrein overexpression alleviates cardiac aging by alternatively regulating macrophage polarization in aged rats.

Deletion of the fih gene encoding an inhibitor of hypoxia-inducible factors increases hypoxia tolerance in zebrafish

Many aerobic organisms have developed molecular mechanism to tolerate hypoxia, but the specifics of these mechanisms remain poorly understood. It is important to develop genetic methods that confer increased hypoxia tolerance to intensively farmed aquatic species, as these are maintained in environments with limited available oxygen. As an asparaginyl hydroxylase of hypoxia-inducible factors (HIFs), factor inhibiting HIF (FIH) inhibits transcriptional activation of hypoxia-inducible genes by blocking the association of HIFs with the transcriptional coactivators CREB-binding protein (CBP) and p300. Therefore, here we sought to test whether fih is involved in regulating hypoxia tolerance in the commonly used zebrafish model. Overexpressing the zebrafish fih gene in epithelioma papulosum cyprini (EPC) cells and embryos, we found that fih inhibits the transcriptional activation of zebrafish HIF-α proteins. Using CRISPR/Cas9 to obtain fih-null zebrafish mutants, we noted that the fih deletion makes zebrafish more tolerant of hypoxic conditions than their WT siblings, but does not result in oxygen consumption rates that significantly differ from those of WT fish. Of note, we identified fewer apoptotic cells in adult fih-null zebrafish brains and in fih-null embryos, possibly explaining why the fih-null mutant had greater hypoxia tolerance than the WT. Moreover, the fih deletion up-regulated several hypoxia-inducible genes in fih-null zebrafish exposed to hypoxia. The findings of our study suggest that fih plays a role in hypoxia tolerance by affecting the rate of cellular apoptosis in zebrafish.

Synergistic immunologic targets for the treatment of prostate cancer

Prostate cancer is a common disease and, while detection and treatment have advanced, it remains a significant cause of morbidity and mortality in men. Research suggests significant involvement of the immune system in the pathogenesis and progression of prostate cancer, indicating that immunologic therapies may benefit patients. Two immunologic factors, interleukin-2 and transforming growth factor-β, may be especially attractive therapeutic targets for prostate cancer. Specifically, an increase in interleukin-2 signaling and a decrease in transforming growth factor-β signaling might help improve immunologic recognition and targeting of tumor cells. The purpose of this review is to highlight the evidence that interleukin-2 and blockade of transforming growth factor-β could be used to target prostate cancer based on current understanding of immune function in the context of prostate cancer. Additionally, current treatments related to these two factors for prostate and other cancers will be used to strengthen the argument for this strategy.