Anupama Modi1, Purvi Purohit2, Dipayan Roy1, Jeewan Ram Vishnoi3, Puneet Pareek4, Poonam Elhence5, Priyanka Singh6, Shailja Sharma1, Praveen Sharma1, Sanjeev Misra3. 1. Department of Biochemistry, All India Institute of Medical Sciences (AIIMS), Jodhpur, Rajasthan, India. 2. Department of Biochemistry, All India Institute of Medical Sciences (AIIMS), Jodhpur, Rajasthan, India. purohitp@aiimsjodhpur.edu.in. 3. Department of Surgical Oncology, All India Institute of Medical Sciences (AIIMS), Jodhpur, Rajasthan, India. 4. Department of Radiotherapy, All India Institute of Medical Sciences (AIIMS), Jodhpur, Rajasthan, India. 5. Department of Pathology and Lab Medicine, All India Institute of Medical Sciences (AIIMS), Jodhpur, Rajasthan, India. 6. Department of Bioscience and Bioengineering, Indian Institute of Technology (IIT), Jodhpur, Rajasthan, India.
Abstract
BACKGROUND: Stemness, a key component of breast cancer (BC) heterogeneity, is responsible for chemoresistance. Growth differentiation factor-15 (GDF-15) induces drug resistance and stemness in BC cells. In this study, the expressions and interactions of GDF-15, FOXM1, and stemness (OCT4 and SOX2), and drug resistance (ABCC5) markers were evaluated in BC. METHODS AND RESULTS: 40 diagnosed BC patients and 40 healthy controls were included in this study. Serum GDF-15 was significantly raised (p < 0.001) in BC patients. Expressions of GDF-15, OCT4, SOX2, and FOXM1 in BC tissue and cell lines (MCF-7 and MDA-MB-231) were determined by RT-PCR, while phosphorylated AKT (p-AKT) was analyzed by Western blot. Not only were the fold change expressions higher in cancer tissue as compared to surrounding control tissue, but a higher expression was observed for all the genes along with p-AKT in MDA-MB-231 cells compared to MCF-7. Tissue GDF-15 was significantly associated with ABCC5 (p < 0.001), OCT4 (p = 0.002), SOX2 (p < 0.001), and FOXM1 (p < 0.001). To further analyze the signaling pathway involved in stemness and drug resistance in BC, GDF-15 knockdown was performed, which reduced the expression of p-AKT, FOXM1, OCT4 and SOX2, and ABCC5, whereas recombinant GDF-15 treatment reversed the same. In silico analyses in UALCAN revealed a similar picture for these genes to that of BC tissue expression. CONCLUSIONS: GDF-15 promotes stemness and intrinsic drug resistance in BC, possibly mediated by the p-AKT/FOXM1 axis.
BACKGROUND: Stemness, a key component of breast cancer (BC) heterogeneity, is responsible for chemoresistance. Growth differentiation factor-15 (GDF-15) induces drug resistance and stemness in BC cells. In this study, the expressions and interactions of GDF-15, FOXM1, and stemness (OCT4 and SOX2), and drug resistance (ABCC5) markers were evaluated in BC. METHODS AND RESULTS: 40 diagnosed BC patients and 40 healthy controls were included in this study. Serum GDF-15 was significantly raised (p < 0.001) in BC patients. Expressions of GDF-15, OCT4, SOX2, and FOXM1 in BC tissue and cell lines (MCF-7 and MDA-MB-231) were determined by RT-PCR, while phosphorylated AKT (p-AKT) was analyzed by Western blot. Not only were the fold change expressions higher in cancer tissue as compared to surrounding control tissue, but a higher expression was observed for all the genes along with p-AKT in MDA-MB-231 cells compared to MCF-7. Tissue GDF-15 was significantly associated with ABCC5 (p < 0.001), OCT4 (p = 0.002), SOX2 (p < 0.001), and FOXM1 (p < 0.001). To further analyze the signaling pathway involved in stemness and drug resistance in BC, GDF-15 knockdown was performed, which reduced the expression of p-AKT, FOXM1, OCT4 and SOX2, and ABCC5, whereas recombinant GDF-15 treatment reversed the same. In silico analyses in UALCAN revealed a similar picture for these genes to that of BC tissue expression. CONCLUSIONS: GDF-15 promotes stemness and intrinsic drug resistance in BC, possibly mediated by the p-AKT/FOXM1 axis.
Authors: Sangita Sridharan; Cory M Howard; Augustus M C Tilley; Boopathi Subramaniyan; Amit K Tiwari; Randall J Ruch; Dayanidhi Raman Journal: Front Oncol Date: 2019-10-16 Impact factor: 6.244