Hypoxia-induced apoptosis is blocked by adrenomedullin via upregulation of Bcl-2 in human osteosarcoma cells.

Oncol Rep

Department of Orthopedics, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China.

Published: August 2015

Adrenomedullin (ADM), a multifunctional regulatory peptide, is potentially induced by hypoxia in physiological and pathological tissues, including many types of malignant tumors. Recent research has demonstrated that ADM expression is highly associated with the prognosis and disease severity of human osteosarcoma. However, the effect of ADM on the apoptosis of osteosarcoma cells and its possible mechanism remain to be elucidated. In the present study, we observed that mRNA and protein levels of ADM were increased in human osteosarcoma SOSP-F5M2 cells under a hypoxic microenvironment induced by cobalt chloride (CoCl2) in a time-dependent manner. Treatment with ADM significantly blunted hypoxic-induced apoptosis, evaluated by Hoechst 33342 staining and Annexin V-FITC/PI labeling. The expression of B-cell lymphoma-2 (Bcl-2) was increased by administration of ADM; meanwhile, this effect was reversed by exogenously adding U0126, a selective inhibitor of MEK or ADM22-52 (ADM-specific receptor antagonist). These results demonstrated that ADM acted as a survival factor to inhibit hypoxic-induced apoptosis via interacting with its receptors CRLR-RAMP (2,3) in osteosarcoma cells. The anti-apoptotic function of ADM was found to be mediated by upregulation of the expression of Bcl-2 partially through activation of the MEK/ERK1/2 signaling pathway. Therefore, targeting of the ADM/ADM acceptors/ERK1/2/Bcl-2 pathway may provide a potential strategy through which to induce the apoptosis of osteosarcoma cells.

Download full-text PDF

Source
http://dx.doi.org/10.3892/or.2015.4011DOI Listing

Publication Analysis

Top Keywords

osteosarcoma cells
16
human osteosarcoma
12
adm
8
demonstrated adm
8
apoptosis osteosarcoma
8
hypoxic-induced apoptosis
8
osteosarcoma
6
cells
5
hypoxia-induced apoptosis
4
apoptosis blocked
4

Similar Publications

Introduction: This study utilized a injectable curcumin (Cur)-infused calcium phosphate silicate cement (CPSC) for addressing defects caused by bone cancer, and evaluated its promoting bone regeneration and exerting cytotoxic effects on osteosarcoma cells.

Methods: The material's physicochemical properties, biocompatibility with osteoblasts, and cytotoxicity toward osteosarcoma cells were rigorously analyzed.

Results: The findings demonstrate that CPSC-Cur signicantly prolongs the setting time, which can be optimized by adding silanized cellulose nanober (CNF-SH) to achieve a balance between workability and mechanical strength.

View Article and Find Full Text PDF

Design, synthesis, and biological evaluation of Flavokavain B derivatives as potent TRF2 inhibitors for the treatment of Osteosarcoma.

Eur J Med Chem

January 2025

Chemical Biology Research Center at School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, People's Republic of China. Electronic address:

Telomere repeat-binding factor 2 (TRF2) is a crucial component of the shelterin complex, commonly overexpressed in osteosarcoma (OS) and positively correlated with its progression. To date, effective TRF2 inhibitors for in vivo applications remain limited. In this study, a series of Flavokavain B derivatives were designed and synthesized, and their TRF2 inhibition and antitumor activity were evaluated.

View Article and Find Full Text PDF

Enzyme-enzyme interactions are fundamental to the function of cells. Their atomistic mechanisms remain elusive mainly due to limitations of in-cell measurements. We address this challenge by atomistically modeling, for a total of ≈80 μs, a slice of the human cell cytoplasm that includes three successive enzymes along the glycolytic pathway: glyceraldehyde-3-phosphate dehydrogenase (GAPDH), phosphoglycerate kinase (PGK), and phosphoglycerate mutase (PGM).

View Article and Find Full Text PDF

Background: Osteosarcoma is the most common malignant bone tumour with limited treatment options and poor outcomes in advanced metastatic cases. Current immunotherapies show limited efficacy, highlighting the need for novel therapeutic approaches. Systemic immune activation by Toll-like receptor 4 (TLR4) immunostimulants has shown great promise; however, current TLR4 agonists' toxicity hinders this systemic approach in patients with osteosarcoma.

View Article and Find Full Text PDF

iRGD-Targeted Biosynthetic Nanobubbles for Ultrasound Molecular Imaging of Osteosarcoma.

Int J Nanomedicine

January 2025

Department of Ultrasound, The second People's Hospital of Shenzhen, The First Affiliated Hospital of Shenzhen University, Shenzhen, 518061, People's Republic of China.

Purpose: Osteosarcoma is the most common primary malignant tumor of the bone. However, there is a lack of effective means for early diagnosis due to the heterogeneity of tumors and the complexity of tumor microenvironment. αvβ3 integrin, a crucial role in the growth and spread of tumors, is not only an effective biomarker for cancer angiogenesis, but also highly expressed in many tumor cells.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!