bims-stacyt 2018-10-28 papers

on Metabolism and the paracrine crosstalk between cancer and the organism

Issue of 2018–10–28
two papers selected by
Cristina Muñoz Pinedo, L’Institut d’Investigació Biomèdica de Bellvitge

Interleukin-6 (IL-6) triggers the malignancy of hemangioma cells via activation of HIF-1α/VEGFA signals.
YAP via interacting with STAT3 regulates VEGF-induced angiogenesis in human retinal microvascular endothelial cells.

Eur J Pharmacol. 2018 Oct 18. pii: S0014-2999(18)30609-5. [Epub ahead of print]

Interleukin-6 (IL-6) triggers the malignancy of hemangioma cells via activation of HIF-1α/VEGFA signals.

Xiaoyang Fu, Shuiting Zhai, Ji Yuan.

  Hemangioma (HA) is tumor formed by hyper-proliferation of vascular endothelial cells. The roles of interleukins on the progression of HA are not well illustrated. Our present study revealed that the expression of interleukin -6 (IL-6) and IL-8 in HA cells were significantly increased as compared with that in the human umbilical vein endothelial cell (HUVEC) cells. Targeted inhibition of IL-6, while not IL-8, can significantly suppress the proliferation and migration of HA cells. IL-6 treatment can increase the expression of vascular endothelial growth factor A (VEGFA), while had no significant effect on the expression of basic fibroblast growth factor (bFGF), in HA cells. Deletion of VEGFA can abolish IL-6 induced progression of HA, suggesting the essential role of VEGFA in IL-6 induced HA development. The specific inhibitor of hypoxia-inducible factor (HIF)-1α, while not Sp1, NF-κB, or AP1, abolished IL-6 induced VEGFA expression. Over expression of HIF-1α can attenuate anti-IL-6 suppressed expression of VEGFA in HA cells. Furthermore, IL-6 triggered the expression, nuclear translocation, and transcription activities of HIF-1α in HA cells via increasing its binding with the signal transducer and activator of transcription-3 (STAT3). STAT3 inhibitor CPA7 or si-STAT3 can abolish IL-6 induced upregulation of HIF-1α in HDEC cells. Collectively, our study revealed that IL-6 can trigger the malignancy of HA cells via induction of proliferation and migration. The activation of STAT3/HIF-1α/VEGFA signal was essential for this process. It suggested that IL-6/STAT3/HIF-1α/VEGFA signal may represent a novel therapeutic target for human HA treatment.

Keywords:  HIF-1α; Hemangioma; IL-6; invasion; proliferation

DOI:  https://doi.org/10.1016/j.ejphar.2018.10.022
Exp Cell Res. 2018 Oct 17. pii: S0014-4827(18)30696-7. [Epub ahead of print]

YAP via interacting with STAT3 regulates VEGF-induced angiogenesis in human retinal microvascular endothelial cells.

Manhui Zhu, Xiaojuan Liu, Ying Wang, Lili Chen, Li Wang, Xiao Qin, Jiaowen Xu, Lele Li, Yuanyuan Tu, Taohu Zhou, E Song, Aimin Sang.

Endothelial dysfunction is a main feature of retinal neovascular diseases which are the leading cause of blindness in developed countries. Yes-associated protein (YAP) and signal transducer and activator of transcription factor 3 (STAT3) participate in angiogenesis via vascular endothelial growth factor (VEGF) signaling. Additionally, YAP can bind STAT3 in endothelial cells. In the study, dimethyloxalylglycine (DMOG) stimulated human retinal microvascular endothelial cells (HRMECs) was used as retinal endothelial hypoxia model. The proliferation of HRMECs, as well as t-YAP, p-STAT3 (Tyr705) increased, while p-YAP (Ser127), p-YAP (Ser397) decreased following hypoxia. Meanwhile, YAP and STAT3 translocated to the nucleus. YAP knockdown inhibited the proliferation, migration and tube formation of HRMECs. YAP overexpression up-regulated phosphorylation of STAT3. The YAP overexpression-induced HRMECs proliferation, migration and tube formation were reversed by S3I-201, a selective STAT3 inhibitor. YAP interacted with STAT3 to promote STAT3 nuclear translocation. Additionally, YAP and STAT3 promoted the transcription of VEGF synergistically. Finally, inhibition of YAP alleviated retinal pathological neovascularization in mouse oxygen-induced retinopathy (OIR) model. In summary, activated YAP interacted with STAT3 to promote the activation and nuclear translocation of STAT3, hence boosted the proliferation, migration and tube formation of HRMECs via VEGF signaling following hypoxia. The data will further elucidate the mechanisms of retinal neovascular diseases.

DOI: https://doi.org/10.1016/j.yexcr.2018.10.007