Journal: PLOS Biology
Article Title: The mTORC2 subunit RICTOR drives breast cancer progression by promoting ganglioside biosynthesis through transcriptional and epigenetic mechanisms
doi: 10.1371/journal.pbio.3003362
Figure Lengend Snippet: (A) A schematic diagram showing the workflow to identify RICTOR-regulated transcription factors that bind to the UGCG promoter. (B) Results from qRT-PCR (mean ± SEM, n = 3) confirm reduced expression of RICTOR-regulated ELF1 , ZFX , and CTCF transcription factors in MCF-7_RICTOR SH cells. (C) ChIP-qPCR (mean ± SEM, n = 3) results show reduced binding of ZFX to UGCG promoter in MCF-7_RICTOR SH cells. (D) EMSA shows the binding of ZFX to UGCG promoter (lanes 2 and 3) in MCF-7_ZFX OE cells, shift-ablation assay in MCF-7_ZFX OE cells (lane 4), competition assay with specific (lane 5) and unrelated oligo as a control (lane 6). “*” denotes nonspecific complexes. (E) EMSA comparing endogenous ZFX-DNA binding activity in MCF-7_SCRAM SH and MCF-7_RICTOR SH cells. (F, G) Immunoblots (F) and their quantification (mean ± SEM, n = 3) (G) confirm downregulation of ZFX in MCF-7_RICTOR SH cells. ( H , I ) Immunoblots (H) and their quantification (mean ± SEM, n = 3) (I) confirm overexpression and silencing of ZFX in MCF-7_ZFX OE and MCF-7_ZFX SL cells. (J, K) Immunoblots (J) and their quantification (mean ± SEM, n = 3) (K) show upregulation and downregulation of UGCG upon overexpression and silencing of ZFX in MCF-7_ZFX OE and MCF-7_ZFX SL cells. (L, M) Fold change (mean ± SEM, n = 5) in ceramides (L) and glucosylceramides (M) confirms a decrease in ceramides and an increase in glucosylceramides in MCF-7_ZFX OE cells. In contrast, MCF-7_ZFX SL cells show higher ceramides and reduced glucosylceramides. (N–R) Absolute quantification (mean ± SEM, n = 3-5) of GM3 (N), GD3 (O), GD2 (P), GM2 (Q), and GM1 (R) gangliosides shows an increase in GM3, GD3, and GM2 gangliosides and attenuated GM1 gangliosides on ZFX overexpression in MCF-7 cells. (S) Cell proliferation (mean ± SEM, n = 4) demonstrates increased proliferation of MCF-7_ZFX OE cells, whereas MCF-7_ZFX SL cells show reduced cell proliferation. (T) Tumor growth kinetics recorded a significantly higher growth of MCF-7_ZFX OE (mean ± SEM, n = 4-6) than MCF-7_VECT OE tumors. ( U , V ) Cell proliferation demonstrates a decrease in proliferation of MCF-7_ZFX OE cells on UGCG silencing (U) (mean ± SEM, n = 4), whereas MCF-7_ZFX SH cells show enhanced cell proliferation on UGCG overexpression (mean ± SEM, n = 3) (V). ( W ) siRNA-mediated silencing of UGCG leads to reduced tumor growth kinetics in MCF-7_ZFX OE tumors. Data among two groups were analyzed using an unpaired Student t test, among multiple groups using One-way ANOVA, and by Two-way ANOVA in time-dependent studies. p -value: * p < 0.05, ** p < 0.01, *** p < 0.0005, **** p < 0.0001. Numerical data can be found in .
Article Snippet: MCF-7, BT-474, MDA-MB-453, HCT-116, HEK-293 cells (ATCC, USA), DMEM media (Cat# D5648) Sigma, USA, MEBM media (Cat# CC-3151) Lonza, Switzerland, MEM media (Cat# AL081) HiMedia, USA, DPBS (Cat# D5652) Sigma, USA, FBS (Cat# 10270) Gibco, USA, lipid-free FBS (Cat# S148L) Biowest, USA, Penicillin-Streptomycin (Cat# 113-98-43810-74-0) HyClone, USA, Lipofectamine 2000, (Cat# 11668019) Invitrogen, USA, Lipofectamine 3000 (Cat# L3000015) Invitrogen, USA, Trypsin (Cat# TCL007) HiMedia, USA, Puromycin (Cat# P7255) Sigma, USA, G418 (Cat# A1720) Sigma, USA, Haemocytometer (Cat# Z359629) Bright-Line, USA, shRNA Control (Cat# SHC202V) Sigma, USA, shRNA RICTOR Virus Particles (Cat# SHCLNV, TRCN0000289691, TRCN0000307119, TRCN0000296313, TRCN0000307122) Sigma, USA, shRNA RICTOR Glycerol stocks (SHCLNG, TRCN0000296313, TRCN0000307122,), Sigma, USA, shRNA UGCG Glycerol stocks (SHCLNG, TRCN0000036128, TRCN0000036126, TRCN0000300623) Sigma, USA, ZFX Glycerol stocks (Cat# SHCLNG TRCN0000017308, TRCN0000017309, TRCN0000017310), Sigma, USA, shRNA ST8SIA1 (Cat# SHCLNG TRCN0000417447, TRCN0000036044, TRCN0000036046), Sigma, USA, UGCG siRNA (Cat# AM51331) Ambion, USA, ZFX siRNA (Cat# L-006572-00-0005) Dharmacon, USA, Scrambled siRNA (Cat# D-001810-10-05) Dharmacon, USA, GD3 Synthase (ST8SIA1) siRNA (Cat# EHU025731-20UG) Merck, USA, 5-Aza-2′-deoxycytidine (DAC) (Cat#A3656-10MG) Sigma, USA, KDOAM25 Hydrochloride hydrate (Cat# SML2774-5MG) Sigma, USA, MK-2206 dihydrochloride (Cat# HY-10358) MedChem Express, USA, Eliglustat (Cat# HY-14885) MedChem Express, USA, Hygromycin (Cat# PCT1503), HiMedia, USA, Puromycin (Cat# P8833), Sigma, USA.
Techniques: Quantitative RT-PCR, Expressing, ChIP-qPCR, Binding Assay, Competitive Binding Assay, Control, Activity Assay, Western Blot, Over Expression, Quantitative Proteomics