Lean adipocyte oxylipin signaling restrains breast cancer through ferroptosis.

September 10, 2026| Source: Science (New York, N.Y.)

Obesity increases breast cancer risk and tumor aggressiveness, yet the mechanisms underlying this association remain unclear. In this work, we identify a tumor-suppressive lipid signaling pathway in which mammary adipocytes secrete the oxylipin 9S-hydroxyoctadecadienoic acid (9S-HODE). 9S-HODE induces ferroptosis in breast cancer cells by disrupting iron homeostasis. Adipocytes in obese mammary tissue produce less 9S-HODE, and tumors in obese mice exhibit reduced ferroptosis. Accordingly, ferroptosis inhibition accelerates tumor growth in lean mice, and restoring 9S-HODE suppresses tumor growth in obese mice. In humans, mammary 9S-HODE content is inversely correlated with body mass index, and 9S-HODE inhibits patient-derived breast cancer organoid growth. These findings identify the loss of adipocyte-derived 9S-HODE as a mechanism by which obesity promotes breast cancer and suggest that the restoration of ferroptosis-inducing lipid signaling may be a therapeutic strategy.

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PLASTID ENVELOPE ION CHANNELS (PEC1/2) link Ca 2+ and jasmonic acid signaling in plant cells.

Plants constantly encounter adverse environmental interactions. One organelle is particularly specialized in stress signaling and phytohormone synthesis: the plastid. Calcium (Ca 2+ ), a key second messenger, is known to intersect with cellular phytohormone signaling networks. While cytosolic Ca 2+ dynamics have been studied extensively, the physiological relevance of stromal Ca 2+ transients and the identity of channels mediating rapid Ca 2+ flux into plastids remain largely unexplored. In this

Health & MedicineSeptember 28, 2026

Structural insights into fosfomycin efflux by a streptococcal ABC transporter.

Gram-positive bacteria encode a broad array of ABC transporters that mediate substrate translocation across the cell membrane, with some contributing to their survival under environmental stresses such as antimicrobial exposure. While several of these transporters have been shown to exhibit multidrug efflux activity, the functional roles of many others remain unknown. Here, using an efflux pump screen in the opportunistic human pathogen Streptococcus pneumoniae , we identified a previously uncha

Health & MedicineSeptember 26, 2026

Detection of "hidden" mitotic crossovers by long-read DNA sequencing.

Mitotic crossovers in diploid organisms are usually detected by looking for loss of heterozygosity (LOH) for a marker. Assuming the crossover occurs between two duplicated chromatids, a single reciprocal crossover will result in two recombinant chromatids and two nonrecombinant chromatids. LOH will only be observed when a recombinant chromatid cosegregates with a nonrecombinant chromatid. Cells containing both recombinant chromosomes will not result in LOH. Below, we use long-range DNA sequencin

Health & MedicineSeptember 26, 2026

Amino acid homeostasis by CORVET/HOPS: A metabolic and stress resilience checkpoint for T cells.

Amino acid sufficiency is critical for T cell metabolic reprogramming, yet how T cells maintain amino acid homeostasis remains poorly defined. Here, we identify the CORVET and HOPS (CORVET/HOPS) tethering complexes as essential upstream regulators. In activated T cells, they sustain intracellular amino acid levels by promoting macropinocytosis to acquire extracellular nutrients. This function enables dual signaling outcomes: suppression of the integrated stress response (ISR) and activation of m

Health & MedicineSeptember 25, 2026

Bright monomeric fluorescent protein elite-niRFP704 for two-channel near-infrared STED nanoscopy.

The near-infrared (NIR) spectral region is attractive for live-cell imaging, due to low autofluorescence and reduced phototoxicity. Some phytochrome-derived fluorescent proteins absorb and emit fluorescence in the NIR, but have short fluorescence lifetimes and relatively low quantum yields, requiring higher laser powers thus limiting their usefulness for live-cell superresolution microscopy. Using the bacterial phytochrome miRFP703 as a template, we screened for variants with longer fluorescence