Research Papers:

Differential silencing of STAT3 isoforms leads to changes in STAT3 activation

Inbal Shamir, Ilan Tsarfaty, Gidi Paret and Yael Nevo-Caspi _

PDF  |  Full Text  |  Supplementary Files  |  How to cite  |  Press Release

Oncotarget. 2023; 14:366-376. https://doi.org/10.18632/oncotarget.28412

Metrics: PDF 423 views  |   Full Text 1434 views  |   ?  


Inbal Shamir1, Ilan Tsarfaty2, Gidi Paret1,* and Yael Nevo-Caspi1,*

1 Department of Pediatric Critical Care Medicine, Safra Children’s Hospital, Sheba Medical Center, Ramat-Gan, Israel

2 Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel

* These authors contributed equally to this work

Correspondence to:

Yael Nevo-Caspi, email: [email protected]

Keywords: STAT3; STAT3 isoforms; breast cancer; cancer diagnosis; cancer therapy

Abbreviations: STAT3: Signal transducer and activator of transcription 3; ER: endoplasmic reticulum; TAD: transactivation domain; SH2: Src homology 2; RQ: Relative quantitative

Received: November 14, 2022     Accepted: April 13, 2023     Published: April 24, 2023

Copyright: © 2023 Shamir et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Signal transducer and activator of transcription 3 (STAT3) is a transcription factor involved in multiple fundamental biological processes and a key player in cancer development and progression. STAT3 is activated upon tyrosine phosphorylation and is constitutively active in various malignancies; therefore, the expression of pSTAT3 has been recognized as a predictor of poor survival. STAT3 encodes two alternatively-spliced STAT3 isoforms: the full-length STAT3α isoform and the truncated STAT3β isoform. These isoforms have been suggested as the reason for the occasionally observed opposing roles of STAT3 in cancer: an oncogene, on one hand, and a tumor suppressor on the other. To investigate their roles in aggressive breast cancer, we separately silenced each isoform and found that they affect each other’s activation, impacting cell viability, cytokine expression, and migration. Silencing specific isoforms can lead to a more favorable balance of activated STAT3 proteins in the cell. Distinguishing between the two isoforms and their active forms is crucial for STAT3-related cancer diagnosis and therapy.

Creative Commons License All site content, except where otherwise noted, is licensed under a Creative Commons Attribution 4.0 License.
PII: 28412