Kinome-Wide siRNA Screening Identifies Src-Enhanced Resistance of Chemotherapeutic Drugs in Triple-Negative Breast Cancer Cells

Abstract

Background: Chemotherapy is the main treatment for triple-negative breast cancer (TNBC), which lack molecular markers for diagnosis and therapy. Cancer cells activate chemoresistant pathways and lead to therapeutic failure for patients with TNBC. Several kinases have been identified as chemoresistant genes. However, the involvement of kinases in the chemoresistance in TNBC cells is not fully understood.Methods: We employed a kinome siRNA library to screen whether targeting any kinases could increase the chemosensitivity of TNBC cell lines. The effects of kinase on cell viability in various breast cancer cells were validated with ATP level and colony formation. Protein expression and phosphorylation were determined by immunoblotting. The Cancer Genome Atlas (TCGA) dataset was collected to analyze the correlation of Src expression with prognosis of TNBC patients.Results: Primary screening and validation for the initial hits showed that Src kinase was a potential doxorubicin-resistant kinase in the TNBC cell lines MDA-MB-231 and Hs578T. Both siRNA against Src and the Src inhibitor dasatinib enhanced the cytotoxic effects of doxorubicin in TNBC cells. Moreover, phosphorylation of AKT and signal transducer and activator of transcription 3 (STAT3), downstream effectors of Src, were accordingly decreased in Src-silenced or -inhibited TNBC cells. Additionally, TCGA data analysis indicated that Src expression levels in tumor tissues were higher than those in tumor-adjacent normal tissues in patients with TNBC. High co-expression level of Src and STAT3 was also significantly correlated with poor prognosis in patients.Conclusion: Our results showed that Src-STAT3 axis might be involved in chemoresistance of TNBC cells.

Role of STAT3 signaling pathway in breast cancer

“…5. Tzeng et al have indicated that the Src/STAT3 signaling pathway is involved in multidrug resistance in triple negative breast cancer cells [64]. It is also found that crosstalk between breast cancer cells and macrophages can induce tamoxifen and ICI 182,780 resistance through the NF-κB/STAT3/ERK pathways [65].…”

Transcription Factors in Cancer Development and Therapy

“…This also involves Slug, MAPK and PI3K/AKT axes. Ovarian cancer Cisplatin [192] ID1 mediates resistance via STAT3-mediated induction of ATF6 transcription to induce autophagy Ovarian cancer Paclitaxel and cisplatin [193] Involvement of Src/STAT3 signaling pathway in chemotherapy resistance Triple negative breast cancer Camptothecin, Doxorubicin [194] HIF-1 HIF-1 induced carbonic anhydrase IX expression. Inhibition of carbonic anhydrase IX restored chemo-sensitivity against vinorelbine Lung cancer Vinorelbine [195] HIF-2α overexpression increased the expression of stem cell markers (c-Myc, OCT4, Nanog) and Paclitaxel-resistance.…”

A kinome‐wide screen using a NanoLuc LATS luminescent biosensor identifies ALK as a novel regulator of the Hippo pathway in tumorigenesis and immune evasion

“…Although the roles of individual kinases in various biologic and pathologic processes have been extensively studied in the past, few kinome-wide studies have been performed. Recently, siRNA or short hairpin RNA and clustered regularly interspaced short palindromic repeats functional genomic screens were used for a kinome-wide screen of kinases regulating biologic functions, such as cell proliferation and drug resistance (34)(35)(36)(37)(38). However, there are currently few kinome-wide screenings for kinases affecting the activity of a specific protein.…”