American Association for Cancer Research
15417786mcr140088t-sup-127105_2_supp_2537942_n7t5qh.docx (348.46 kB)

Data Supplement from Unbiased Proteomic and Transcript Analyses Reveal that Stathmin-1 Silencing Inhibits Colorectal Cancer Metastasis and Sensitizes to 5-Fluorouracil Treatment

Download (348.46 kB)
journal contribution
posted on 2023-04-03, 16:20 authored by Wei Wu, Xing Fei Tan, Hwee Tong Tan, Teck Kwang Lim, Maxey Ching Ming Chung

Figure S1: Caspase 6 silencing in STMN1 KD cells abrogates 5FU sensitisation. Figure S2: Caspase 6 is the apical caspase in STMN1 silencing-induced 5FU sensitization.



Colorectal cancer metastasis is a major cause of mortality worldwide, which may only be controlled with novel methods limiting tumor dissemination and chemoresistance. High stathmin-1 (STMN1) expression was previously established as a hallmark of colorectal cancer progression and predictor of poor survival; however, the mechanism of action is less clear. This work demonstrates that STMN1 silencing arrests tumor-disseminative cascades by inhibiting multiple metastatic drivers, and repressing oncogenic and mesenchymal transcription. Using a sensitive iTRAQ labeling proteomic approach that quantified differential abundance of 4562 proteins, targeting STMN1 expression was shown to reinstate the default cellular program of metastatic inhibition, and promote cellular adhesion via amplification of hemidesmosomal junctions and intermediate filament tethering. Silencing STMN1 also significantly improved chemoresponse to the classical colorectal cancer therapeutic agent, 5FU, via a novel caspase-6 (CASP6)–dependent mechanism. Interestingly, the prometastatic function of STMN1 was independent of p53 but required phosphorylations at S25 or S38; abrogating phosphorylative events may constitute an alternative route to achieving metastatic inhibition. These findings establish STMN1 as a potential target in antimetastatic therapy, and demonstrate the power of an approach coupling proteomics and transcript analyses in the global assessment of treatment benefits and potential side-effects.Implications: Stathmin-1 is a potential candidate in colorectal cancer therapy that targets simultaneously the twin problems of metastatic spread and chemoresistance. Mol Cancer Res; 12(12); 1717–28. ©2014 AACR.