Fate-mapping post-hypoxic tumor cells reveals a ROS-resistant phenotype that promotes metastasis

Abstract

Hypoxia is known to be detrimental in cancer and contributes to its development. In this work, we present an approach to fate-map hypoxic cells in vivo in order to determine their cellular response to physiological O2 gradients as well as to quantify their contribution to metastatic spread. We demonstrate the ability of the system to fate-map hypoxic cells in 2D, and in 3D spheroids and organoids. We identify distinct gene expression patterns in cells that experienced intratumoral hypoxia in vivo compared to cells exposed to hypoxia in vitro. The intratumoral hypoxia gene-signature is a better prognostic indicator for distant metastasis-free survival. Post-hypoxic tumor cells have an ROS-resistant phenotype that provides a survival advantage in the bloodstream and promotes their ability to establish overt metastasis. Post-hypoxic cells retain an increase in the expression of a subset of hypoxia-inducible genes at the metastatic site, suggesting the possibility of a ‘hypoxic memory.’

Functionalization of Ti substrate with pH‐responsive naringin‐ZnO nanoparticles for the reconstruction of large bony after osteosarcoma resection

“…Additionally, ROS produced by sublethal levels of antibiotics induces antibiotic resistance, but ROS triggered by lethal levels of antibiotics promotes bacterial killing and suppresses resistance (Van Acker & Coenye, 2017; Zhao, Hong, & Drlica, 2014). As a critical factor affecting several cancer hallmarks, ROS is also involved in the acquisition of self‐sufficiency in proliferation signals by a ligand‐independent receptor tyrosine kinase transactivation as well as the loss of contact inhibition and anchorage‐dependence cell growth (Godet et al, 2019; Ishikawa et al, 2008; Poillet‐Perez, Despouy, Delage‐Mourroux, & Boyer‐Guittaut, 2015; Wang, Hou, Su, Zhao, & Shi, 2017). Moreover, ROS can affect many signaling pathways, including mitogen‐activated protein kinases signaling pathways (MAPK) (Avisetti, Babu, & Kalivendi, 2014; Shen & Liu, 2006; Zibara et al, 2017).…”

A lineage-tracing tool to map the fate of hypoxic tumour cells

“…Because the MARCer construct is constitutively expressed, short episodes of hypoxia could induce labelling, but this may not be seen in proximity to EF5 due to re-oxygenation between the time tamoxifen was given and injection of EF5. Other research has also shown that hypoxic cells move out of hypoxic EF5 + or pimonidazole + areas (Harada et al, 2012;Erapaneedi et al, 2016;Conway et al, 2018;Godet et al, 2019) followed by random distribution. The transient nature of the hypoxic state may explain that the induction of tdTomato expression does not correlate with the level of acute hypoxia 2, 5, 9, 16, 21 days later.…”

“…This is likely due to the requirement of O2 for GFP folding and fluorescence (Heim et al, 1994;Kumagai et al, 2013), making it a suboptimal fluorescent marker to track current hypoxia. On the other hand, Godet et al were able to visualise GFP under 0.5% O2 (Godet et al, 2019). Also, processing of the samples exposes them to atmospheric oxygen, possibly introducing enough oxygen for GFP maturation ex vivo.…”

“…Although many of the molecular mechanisms of how cells respond to hypoxia are known, how the hypoxic cells may contribute to poor prognosis is still poorly understood. It is known that hypoxic cells are more resistant to treatment and more likely to disseminate and develop into metastases (Harada et al, 2012;Muz et al, 2015;Godet et al, 2019). However, a direct demonstration of the cell autonomous phenotypes of hypoxic tumour cells within the primary tumour and their interplay with the tumour microenvironment remains understudied.…”

“…Godet et al recently showed through an alternative hypoxia lineage tracing system, that post-hypoxic tumour cells in mice maintain a ROS-resistant phenotype. This provides a survival advantage in the blood stream therefore promoting their ability to form distant metastases (Godet et al, 2019). One limitation of the aforementioned systems is the relatively long time in continuous hypoxia needed before labelling of cells was achieved, limiting the systems predominantly to areas of sustained chronic hypoxia.…”