Dataset Information

Brusatol, a Nrf2 Inhibitor Targets STAT3 Signaling Cascade in Head and Neck Squamous Cell Carcinoma.

ABSTRACT: STAT3 is a latent transcription factor that plays a vital role in the transmission of extracellular signal from receptors to the nucleus. It has been regarded as a master transcription factor due to its role in the regulation of a broad spectrum of genes, which can contribute to oncogenesis. Persistent activation of STAT3 and deregulation of its signaling has been observed in various human cancers including head and neck squamous cell carcinoma (HNSCC). In the present work, we identified brusatol (BT) as a potential blocker of STAT3 signaling pathway in diverse HNSCC cells. The data from the cell-based experiments suggested that BT-induced cytotoxicity and abrogated the activation of STAT3 and that of upstream kinases such as JAK1, JAK2, and Src. It reduced the levels of nuclear STAT3 and its DNA binding ability. BT treatment increased annexin-V-positive cells, promoted procaspase-3 and PARP cleavage, and downregulated the mRNA and protein expression of diverse proteins (Bcl-2, Bcl-xl, survivin) in HNSCC cells. Taken together, brusatol can function as a promising inhibitor targeting STAT3 signaling pathway in HNSCC.

SUBMITTER: Lee JH

PROVIDER: S-EPMC6843503 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Brusatol, a Nrf2 Inhibitor Targets STAT3 Signaling Cascade in Head and Neck Squamous Cell Carcinoma.

Lee Jong Hyun JH Rangappa Shobith S Mohan Chakrabhavi Dhananjaya CD Sethi Gautam G Lin Zhi-Xiu ZX Rangappa Kanchugarakoppal S KS Ahn Kwang Seok KS

Biomolecules 20190930 10

STAT3 is a latent transcription factor that plays a vital role in the transmission of extracellular signal from receptors to the nucleus. It has been regarded as a master transcription factor due to its role in the regulation of a broad spectrum of genes, which can contribute to oncogenesis. Persistent activation of STAT3 and deregulation of its signaling has been observed in various human cancers including head and neck squamous cell carcinoma (HNSCC). In the present work, we identified brusato ...[more]

PMID: 31575007

Similar Datasets

Project description:Patients who have undergone curative?intent therapy for head and neck squamous cell carcinoma (HNSCC) exhibit a high rate of development of second primary tumors (SPTs), which are frequently lethal. A chemoprevention strategy that prevents SPTs would have a major impact on patient outcomes. Sulforaphane, a naturally?occurring compound derived from cruciferous vegetables exhibits chemopreventive activity against HNSCC in a preclinical model. The effects of sulforaphane are considered to be mediated, in large part, through increased protein expression of the transcription factor nuclear factor erythroid 2?related factor 2 (NRF2). Development of sulforaphane chemoprevention for HNSCC would benefit from the identification of robust biomarkers of sulforaphane activity in HNSCC cells and normal mucosal epithelial cells. The present study revealed that sulforaphane potently induces multiple oxidative stress?associated genes at the RNA and protein levels, in HNSCC cells and Het?1A cells, a non?tumorigenic mucosal epithelial cell line. In the present analysis, HMOX1 and HSPA1A were identified as the most highly upregulated genes following sulforaphane treatment, suggesting their potential value as biomarkers to guide clinical trials. Sulforaphane induction of HMOX1 and HSPA1A was validated in vivo in murine tissues. Furthermore, the impact of sulforaphane treatment of HNSCC cells on the expression levels of natural killer group 2D (NKG2D) and DNAX accessory molecule?1 (DNAM?1) ligands, which are activators of natural killer (NK) cells, was examined. NRF2?dependent upregulation of the NKG2D ligand MICA/B was observed. However, only one of the six HNSCC cell lines studied exhibited enhanced sensitivity to NK cell?mediated killing following sulforaphane treatment, suggesting that this may not be a general mechanism of sulforaphane chemopreventive activity in HNSCC. In summary, the present study identified robust biomarkers of sulforaphane activity in HNSCC and normal tissues, supporting their application in the development of sulforaphane chemoprevention approaches for HNSCC.

Project description:BackgroundDrug resistance limits the treatment effect of cisplatin-based chemotherapy in head and neck squamous cell carcinoma (HNSCC), and the underlying mechanism is not fully understood. The aim of this study was to explore the cause of cisplatin resistance in HNSCC.MethodsWe performed survival and gene set variation analyses based on HNSCC cohorts and identified the critical role of tumor necrosis factor alpha-induced protein 2 (TNFAIP2) in cisplatin-based chemotherapy resistance. Half-maximal inhibitory concentration (IC50) examination, colony formation assays and flow cytometry assays were conducted to examine the role of TNFAIP2 in vitro, while xenograft models in nude mice and 4-nitroquinoline N-oxide (4NQO)-induced HNSCC models in C57BL/6 mice were adopted to verify the effect of TNFAIP2 in vivo. Gene set enrichment analysis (GSEA) and coimmunoprecipitation coupled with mass spectrometry (Co-IP/MS) were performed to determine the mechanism by which TNFAIP2 promotes cisplatin resistance.ResultsHigh expression of TNFAIP2 is associated with a poor prognosis, cisplatin resistance, and low reactive oxygen species (ROS) levels in HNSCC. Specifically, it protects cancer cells from cisplatin-induced apoptosis by inhibiting ROS-mediated c-JUN N-terminal kinase (JNK) phosphorylation. Mechanistically, the DLG motif contained in TNFAIP2 competes with nuclear factor-erythroid 2-related factor 2 (NRF2) by directly binding to the Kelch domain of Kelch-like ECH-associated protein 1 (KEAP1), which prevents NRF2 from undergoing ubiquitin proteasome-mediated degradation. This results in the accumulation of NRF2 and confers cisplatin resistance. Positive correlations between TNFAIP2 protein levels and NRF2 as well as its downstream target genes were validated in HNSCC specimens. Moreover, the small interfering RNA (siRNA) targeting TNFAIP2 significantly enhanced the cisplatin treatment effect in a 4NQO-induced HNSCC mouse model.ConclusionsOur results reveal the antioxidant and cisplatin resistance-regulating roles of the TNFAIP2/KEAP1/NRF2/JNK axis in HNSCC, suggesting that TNFAIP2 might be a potential target in improving the cisplatin treatment effect, particularly for patients with cisplatin resistance.

Dataset Information

Brusatol, a Nrf2 Inhibitor Targets STAT3 Signaling Cascade in Head and Neck Squamous Cell Carcinoma.

Publications

Brusatol, a Nrf2 Inhibitor Targets STAT3 Signaling Cascade in Head and Neck Squamous Cell Carcinoma.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets