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Merging Absolute and Relative Quantitative PCR Data to Quantify STAT3 Splice Variant Transcripts
Published on: October 9, 2016
Serpin B3/B4, activated by STAT3, promote survival of squamous carcinoma cells
Simi T Ahmed1, James E Darnell
1Laboratory of Molecular Cell Biology, The Rockefeller University, New York, NY 10065, USA.
Abstract:
Persistently activated STAT3 contributes to cell survival in many different human cancers. Cancer cell secretion of IL-6 is a frequent basis for persistent STAT3 activation; we show that antibodies against IL-6 or gp-130, the signaling unit of the IL-6 receptor, can abruptly remove persistently activated STAT3 causing prompt disappearance of cysteine proteases of serpin B3/B4 mRNAs, known as squamous cell carcinoma antigens 1 and 2. STAT3 occupies the promoter of serpin B3/B4 before removal and siRNA removal of B3/B4 mRNA caused cell death in HN13 head and neck cancer cells. Thus persistently activated STAT3 is a required part of the continuous activation of B3/B4 genes, which protects tumor cells from dying.
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