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Abstract INTRODUCTION:
Ovarian cancer is the deadliest gynecologic malignancy, with high-grade serous carcinoma (HGSC) accounting for ~70% of cases. HGSC originates in the fallopian tube epithelium and metastasizes to the ovaries and then the omentum. We have found that epinephrine enhances lipid release from omental adipocytes, creating a pro-metastatic microenvironment. Using mass spectrometry imaging (MSI) of 3D co-cultures of HGSC cells, murine omental tissues or adipocyte spheroids, alongside LC-MS(/MS) lipidomic profiling and invasion assays, we investigated this metabolic crosstalk. Our findings support that epinephrine acts as an autocrine signal in the tumor microenvironment to enhance lipid release, fostering HGSC invasion and disease progression. Understanding these interactions offers insight into tumor-microenvironment dynamics and could guide the development of targeted therapies to inhibit HGSC metastasis.
METHODS:
A 3D agarose-based co-culture system was used to model interactions among murine omental tissue or adipocytes, and murine oviductal epithelial (MOE) cells with different mutations, MOE PTENshRNA or MOE SCRshRNA. MALDI-MSI was performed using a Bruker timsTOF fleX at 50 µm spatial resolution in positive reflectron mode. A 50:50 CHCA matrix was applied using an HTX TM-Sprayer. Spatial features enriched in cancer–omentum/adipocyte interaction regions were prioritized for further analysis using SCiLS Lab.
For lipidomic profiling, reverse-phase LC-MS/MS was performed in both positive and negative ionization mode to characterize adipocyte-conditioned media (ACM) generated under β-adrenergic receptor agonist (epinephrine), antagonist (propranolol), or vehicle control treatments. Detected lipid features were annotated by subclass and compared across treatment groups using univariate and multivariate analyses.
Conditioned media were further evaluated for functional effects on tumor cell phenotypes, including proliferation, migration, and invasion assays.
RESULTS:
MSI revealed increased epinephrine signal intensity in 3D co-cultures containing HGSC cells, omental tissue or adipocyte spheroids. Adipocyte-conditioned media generated under epinephrine treatment modestly increased HGSC cell invasion, consistent with a pro-metastatic role of β-adrenergic signaling. In contrast, propranolol treatment reduced this invasive phenotype.
Following optimization of lipid extraction from adipocyte-conditioned media, LC-MS/MS data acquired in positive and negative ionization modes were used to profile lipid subclasses across treatments. Thirteen lipid classes were detected, with sterols (ST) and fatty acids (FA) representing the most abundant classes by lipid counts. While a number of classes were detected, further analysis highlighted that there were limited differences in lipid counts among treatment groups. However, multivariate analyses, including principal component analysis (PCA) and heatmaps, revealed clear treatment-dependent shifts in lipid abundance profiles. Therefore the amount of specific lipids is differentially regulated, rather than presence or absence of a specific species or class. Application of directionality filters identifying reciprocal trends between epinephrine- or propranolol-treated samples relative to vehicle control was used to prioritize biologically relevant features for further validation.
This analysis identified a putative subset of sterol-derived lipids consistently enriched in epinephrine treatment, suggesting a link between β-adrenergic activation and sterol metabolism, whereas fatty acids showed less consistent regulation. Two-dimensional lipid composition maps integrating carbon chain length, unsaturation, and oxygenation further revealed enrichment of oxidized sterol specie, including putative estrogen-related derivatives, supporting a role for β-adrenergic signaling in oxidative lipid remodeling.
CONCLUSION:
Our findings highlight a potential role for epinephrine in modulating lipid dynamics within the HGSC tumor microenvironment. By integrating MALDI MSI and lipidomics, we provide evidence that β-adrenergic signaling promotes lipid release from omental tissues and adipocyte cells, contributing to a pro-metastatic lipid-rich niche. HGSC is typically diagnoses after metastasis with almost all women having omental tumors, which highlights that these results support further investigation of metabolic pathways as potential therapeutic vulnerabilities.
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= Discovery stage. (57.21%, 2026)
= Translation stage. (23.38%, 2026)
= Clinically available. (19.40%, 2026)
