Dataset Information

Hypoxia restores the acidosis-induced inhibition of cancer cell dissemination

ABSTRACT: Acidosis is a hallmark of the tumor microenvironment and has been linked to aggressive cancer behavior, characterized by increased migration, invasion, and metastasis. We herein demonstrate that short-term exposure (24-72 h) to acidic extracellular pH (pHe=6.4) suppresses cell proliferation, metabolism, dissociation from tumor spheroids, and migration in vitro as well as extravasation in chick embryos and mice. Acidosis acutely inhibits motility by downregulating the activity of sodium-hydrogen exchanger isoform-1 (NHE1), which in turn suppresses phosphatidylinositol 3‑kinase (PI3K)/Akt. PI3K/Akt inhibition blocks Yes-associated protein (YAP) translocation to the nucleus, reducing NHE1 and integrin-linked kinase (ILK) expression. The resulting reduction in NHE1-/ILK-dependent migration and ATP production is rescued by hypoxia across cell types. While certain cancer cells can adapt to long-term (>3 weeks) acidosis and acquire an aggressive phenotype, acidosis-induced adaptation is not universal and depends on the cell’s ability to restrain reactive oxygen species overproduction via fatty acid oxidation.

ORGANISM(S): Homo sapiens

PROVIDER: GSE315655 | GEO | 2026/01/11

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:Lactic acidosis and hypoxia are two prominent tumor microenvironmental stresses that are both known to exert important influences on gene expression and phenotypes of cancer cells. But very little is known about the cross-talk and interaction between these two stresses. We performed gene expression analysis of MCF7 cells exposed to lactic acidosis, hypoxia and combined lactic acidosis and hypoxia. We found the hypoxia response elicited under hypoxia was mostly abolished upon simultaneous exposure to lactic acidosis. The repression effects are due to loss of HIF-1Î± protein synthesis under lactic acidosis. In addition, we showed lactic acidosis strongly synergizes with hypoxia to activate the unfold protein response (UPR) and inflammation response which are highly similar to amino acid deprivation responses (AAR). The statistical factor analysis of hypoxia and lactic acidosis responses indicated that ATF4 locus, an important activator in the UPR/AAR pathway, is amplified in subsets of breast tumors and cancer cell lines. Varying ATF4 levels dramatically affect the ability to survive the post-stress recovery from hypoxia and lactic acidosis and may suggest its selection of ATF4 amplification in human cancers. These data suggest that lactic acidosis interacts with hypoxia by both inhibiting the canonical hypoxia response and while activating the UPR and inflammation response. Gain of ATF4 locus may offer survival advantages to allow successful adaptation to frequent fluctuations of oxygen and acidity in tumor microenvironment. Collectively, our studies have provided linkage between the short-term transcriptional responses to the long term selection of the DNA copy number alterations (CNAs) under tumor microenvironmental stresses. RNAs from MCF7 cells exposed to control condition (ambient air ~21% O2, no lactate and neutral pH), lactic acidosis (ambient air, 10 mM Lactate and pH 6.7), hypoxia (1% pO2, no lactate and neutral pH) and the combined lactic acidosis and hypoxia (1% pO2, 10 mM Lactate and pH 6.7) condition for 24 hours were extracted by miRVana kits (Ambion) and hybridized to Affymetrix Human genome 133A 2.0 arrays with standard protocol.

Dataset Information

Hypoxia restores the acidosis-induced inhibition of cancer cell dissemination

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets