Identifying the Transcriptional Response of Cancer and Inflammation-Related Genes in Lung Cells in Relation to Ambient Air Chemical Mixtures in Houston, Texas

Atmospheric pollution represents
a complex mixture of air chemicals
that continually interact and transform, making it difficult to accurately
evaluate associated toxicity responses representative of real-world
exposure. This study leveraged data from a previously published article
and reevaluated lung cell transcriptional response induced by outdoor
atmospheric pollution mixtures using field-based exposure conditions
in the industrialized Houston Ship Channel. The tested hypothesis
was that individual and co-occurring chemicals in the atmosphere relate
to altered expression of critical genes involved in inflammation and
cancer-related processes in lung cells. Human lung cells were exposed
at an air–liquid interface to ambient air mixtures for 4 h,
with experiments replicated across 5 days. Real-time monitoring of
primary and secondary gas-phase pollutants, as well as other atmospheric
conditions, was simultaneously conducted. Transcriptional analysis
of exposed cells identified critical genes showing differential expression
associated with both individual and chemical mixtures. The individual
pollutant identified with the largest amount of associated transcriptional
response was benzene. Tumor necrosis factor (TNF)
and interferon regulatory factor 1 (IRFN1) were identified
as key upstream transcription factor regulators of the cellular response
to benzene. This study is among the first to measure lung cell transcriptional
responses in relation to real-world, gas-phase air mixtures.