Transglutaminase 2 and NF-κB: an odd couple that shapes breast cancer phenotype

Area of Science:

• Molecular Biology
• Cancer Research
• Biochemistry

Background:

• Aberrant activation of the nuclear factor kappa B (NF-κB) transcription factor is linked to drug-resistant phenotypes and aggressive breast tumor behavior due to its pro-survival target genes.
• Transglutaminase 2 (TG2) is an enzyme that activates NF-κB via a non-conventional mechanism, inhibiting IκBα.
• The TG2 gene (TGM2) has been identified as a direct transcriptional target of NF-κB.

Purpose of the Study:

• To review the literature supporting the existence of the TG2/NF-κB signaling loop.
• To elucidate the signal transduction pathways that activate this loop.
• To discuss the phenotypic consequences of aberrant TG2/NF-κB signaling in breast cancer.

Main Methods:

• Literature review of studies investigating the TG2/NF-κB signaling pathway.
• Analysis of molecular mechanisms underlying TG2-mediated NF-κB activation.
• Examination of gene expression data and functional assays related to TGM2 and NF-κB.

Main Results:

• A novel positive feedback loop has been identified where TG2 activates NF-κB, which in turn upregulates TGM2 transcription.
• This TG2/NF-κB signaling loop contributes to the aggressive behavior and drug resistance of breast tumors.
• The aberrant activation of this loop involves specific signal transduction events detailed in the reviewed literature.

Conclusions:

• The TG2/NF-κB signaling loop represents a critical mechanism in breast cancer progression.
• Targeting this feedback loop may offer novel therapeutic strategies for overcoming drug resistance in breast cancer.
• Understanding the intricacies of this molecular loop is essential for developing effective breast cancer treatments.