Mass Spec Roundup: Proteoforms, PFAS, and Volatilomics…

Profiling Pancreatic Cancer with Proteomics

A new study published in PNAS has delivered the first system-level view of how protein conformational changes and phosphorylation interact during communication between pancreatic cancer cells and their surrounding stromal cells – an interaction known to promote drug resistance. The research, led by Lingjun Li, focuses on cocultures of pancreatic ductal adenocarcinoma cells and pancreatic stellate cells, a central component of the tumor microenvironment.

“This study provides the first system-level analysis of the interplay between protein conformational changes and phosphorylation events during cell–cell communication between pancreatic cancer cells and stromal cells using a coculture system,” the authors write. Using a mass spectrometry–based structural proteomics strategy, the team identified 435 proteins that underwent conformational changes during coculture, many associated with core metabolic pathways such as glycolysis and the tricarboxylic acid cycle.

The authors report “a strong association between protein conformational changes and phosphorylation,” showing that phosphorylation can directly influence protein structure and accessibility. Notably, they identify five conformationally regulated metabolic enzymes – ACLY, ACO1, ACO2, IDH1, and OGDH – that “may provide valuable insights into the molecular pathways underlying gemcitabine resistance in pancreatic cancer.”

The team concluded that their findings “provide a framework for understanding tumor–stroma interactions and open avenues for structure-guided, targeted interventions in pancreatic cancer.”

Wipe Test Detects PFAS on Firefighter Gear

A simple, non-destructive wipe test can reveal invisible cancer-linked “forever chemicals” lingering on firefighter gear, according to new research from the University of Miami Miller School of Medicine. The study found per- and polyfluoroalkyl substances (PFAS) on every set of protective equipment tested – including inside breathing masks – highlighting a hidden exposure risk for firefighters.

Led by researchers at Sylvester Comprehensive Cancer Center, the work introduces a practical way to identify contamination without damaging gear. “Think of it as turning on a blacklight in a dark room,” said Alberto Caban-Martinez, co-author of the study. “Suddenly, you see what’s been hiding all along.”

Researchers swabbed high-contact areas of turnout gear and SCBA masks, then analyzed the samples using LC-MS/MS to detect PFAS at nanogram-per-gram levels. The chemicals persisted even in areas intended to deliver clean air. “It’s like smoke that never clears,” said Erin Kobetz. “These chemicals ride home on gear, settle in firehouses, and can end up in the bloodstream.”

Because the method does not harm textiles, it could be used routinely to guide cleaning, storage, and decontamination decisions. “A quick wipe test helps crews make smarter choices – before invisible hazards become lifelong burdens,” said Natasha Schaefer Solle.

High-Resolution Volatilomics Reveals Diet-Microbiome Metabolic Signatures

Researchers have demonstrated that comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOFMS) can systematically map diet-driven changes in the human gut volatilome, offering a detailed view of microbial metabolism that is largely inaccessible using conventional approaches.

In the study, led by Chiara Cordero and published in Analytical and Bioanalytical Chemistry, the team applied GC×GC-TOFMS with optimized headspace solid-phase microextraction to fecal samples from individuals with non-celiac gluten/wheat sensitivity undergoing dietary intervention. The approach resolved approximately 1,000 volatile features per sample, reflecting the chemical diversity of gut-derived metabolites.

From these data, the researchers structurally annotated around 270 compounds, expanding the catalog of known fecal volatiles by roughly 20 percent. Many of the detected molecules were associated with microbial fermentation, including short-chain fatty-acid esters, aldehydes, alcohols, and aromatic compounds.

Multivariate analysis revealed clear metabolic signatures associated with probiotic supplementation. Partial least squares discriminant analysis distinguished probiotic-treated individuals from placebo controls with close to 90 percent classification accuracy, demonstrating that the method can sensitively track functional changes in gut chemistry.

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