Journal: Journal of Cancer Prevention

Article Title: Nuclear Localization of Fibroblast Growth Factor Receptor 1 in Breast Cancer Cells Interacting with Cancer Associated Fibroblasts

doi: 10.15430/jcp.2022.27.1.68

Figure Lengend Snippet: Figure 1. Involvement of FGF2-FGFR1 axisin Akt activation. (A) The effect of CAF-CM on proliferation of breast cancer (MCF-7, MDA-MB-231, and MDA-MB-468) cells was determined by the MTT assay. Cells were incubated with or without CAF-CM for 72 hours. ***Significantly different be- tween the groups compared (P < 0.001). (B) MDA-MB-231 cells were incubated with CAF-CM for the indicated time periods. Phosphorylation of Akt and STAT3 were detected by Western blot analysis. (C) MDA-MB-231 cells were exposed to CAF-CM with or without FGF-2-neutralizing antibody for 3 hours. Phosphorylation of Akt was detected by Western blot analysis. *,***Significantly different between the groups compared (*P < 0.05; ***P < 0.001). (D) MDA-MB-231 cells were treated with 20 ng/mL of FGF2 for the indicated time periods. The phosphorylation of FRS2α as well as Akt was analyzed by Western blot. (E) RNA-seq data set of TCGA breast invasive carcinoma was downloaded from XenaBrower (https://xenabrowser.net). mRNA expression levels of total 1,097 samples (Illumina HiSeq log [normalized counts + 1]) were prepared by quantile normalization. Pearson cor- relation coefficient was calculated to assess the relationship between FGF2 and FGFR1. (F, G) Correlation of FGFR1 protein expression with FGF2 (F) and Akt (G), based on 105 breast invasive carcinoma protein specimens (TCGA, Pan-Cancer Atlas) from the cBioportal database (www.cbiopor- tal.org). FGF2, fibroblast growth factor 2; FGFR1, FGF receptor 1; CAFs, cancer-associated fibroblasts; NFs, normal fibroblasts; CM, conditioned medium; ns, not significantly different; FRS2, FGFR substrate 2; TCGA, The Cancer Genome Atlas; CPTAC, the Clinical Proteomic Tumor Analysis Consortium.

Article Snippet: For neutralization of FGF2 in the CM of CAFs, CM was pre-incubated with 25 μg/mL of human FGF2 antibody or its IgG control (R&D Systems, Inc., Minneapolis, MN, USA) for 1 hour at room temperature prior to use.

Techniques: Activation Assay, MTT Assay, Incubation, Phospho-proteomics, Western Blot, RNA Sequencing, Expressing

Journal: Journal of Cancer Prevention

Article Title: Nuclear Localization of Fibroblast Growth Factor Receptor 1 in Breast Cancer Cells Interacting with Cancer Associated Fibroblasts

doi: 10.15430/jcp.2022.27.1.68

Figure Lengend Snippet: Figure 2. Role of FGFR1 in Akt phosphorylation and breast cancer cell growth and progression. (A) MDA-MB-231 cells were transfected with scrambled or FGFR1 si-RNA for 24 hours. Cells were then incubated with 20 ng/mL of FGF2 for 15 minutes to measure phosphorylated FRS2α. (B) Mice were subjected to xenograft co-injecting with fibroblasts and MDA-MB-231 breast cancer cells. A complex collagen network was detected in H&E-stained tumors by an intense pink and in Masson’s trichrome stain by a blue stain (arrows). Stromal compartment was also detected by α-SMA immunostaining. Magnification, x100. Bars, 100 μm. (C) Phosphorylated Akt in the xenograft tumors was determined by Western blot analysis. *Sig- nificantly different between the groups compared (P < 0.05). (D) Enrichment plots of hallmark gene sets in the high FGFR1-expressing group. FGF2, fibroblast growth factor 2; FGFR1, FGF receptor 1; FRS2, FGFR substrate 2; α-SMA, alpha-smooth muscle actin; CONT, control; EMT, epithelial- mesenchymal transition.

Article Snippet: For neutralization of FGF2 in the CM of CAFs, CM was pre-incubated with 25 μg/mL of human FGF2 antibody or its IgG control (R&D Systems, Inc., Minneapolis, MN, USA) for 1 hour at room temperature prior to use.

Techniques: Phospho-proteomics, Transfection, Incubation, Staining, Immunostaining, Western Blot, Expressing, Control

Journal: Journal of Cancer Prevention

Article Title: Nuclear Localization of Fibroblast Growth Factor Receptor 1 in Breast Cancer Cells Interacting with Cancer Associated Fibroblasts

doi: 10.15430/jcp.2022.27.1.68

Figure Lengend Snippet: Figure 3. The involvement of FGF2-induced ROS generation in nuclear localization of FGFR1. (A) MDA-MB-231 cells were co-cultured with NFs or CAFs for 24 hours. MDA-MB-231 (5 x 10 3 cells) and NFs or CAFs (5 x 10 3 cells) were mixed prior to seeding and incubated for 24 hours. Immunocytochemical analysis was performed using anti-FGFR1 antibody. Cells were then stained with DAPI for detection of nuclei. Magnification, x100. Bars, 200 μm. (B) MDA-MB-231 cells were incubated with FGF2 for 1 hour. Immunocytochemical analysis was performed using anti-FGFR1 antibody. Cells were then stained with PI for detection of nuclei. Magnification, x100. Bars, 200 μm. (C) MDA-MB-231 cells were treated with 20 ng/ mL of FGF2 for 1 hour, followed by Western blot analysis of FGFR1 in cytosolic and nuclear extracts. Lamin B was used as a nuclear marker. *Sig- nificantly different between the groups compared (P < 0.05). (D, E) MDA-MD-231 cells were incubated with CAF-CM or FGF2 for 3 hours and 1 hour, respectively. After staining with DCF-DA for 30 minutes, fluorescent microscopic (D) or flow cytometric (E) analysis was performed to detect intracellu- lar ROS accumulation. Magnification, x40. (F) After pretreatment with NAC for 3 hours, cells were exposed to FGF2 for additional 1 hour. Nuclear ex- tracts were subjected to Western blot analysis to detect the presence of FGFR1 and Nrf2 in the nucleus. **Significantly different between the groups compared (P < 0.01). (G) MDA-MB-231 cells were exposed to FGF2 (20 ng/mL) for 1 hour. Cell lysates were subjected to immunoprecipitation using CBP antibody for 16 hours followed by immunoblotting with. FGFR1 or Nrf2 antibody. FGF2, fibroblast growth factor 2; FGFR1, FGF receptor 1; ROS, reactive oxygen species; CAFs, cancer-associated fibroblasts; CM, conditioned medium; NFs, normal fibroblasts; DAPI, 4′,6-diamidino-2-phenylindole; PI, propidium iodide; CONT, cotrol; DCF-DA, 2’,7’-dichlorodihydrofluorescein diacetate; NAC, N-acetylcysteine; CBP, CREB-binding protein.

Article Snippet: For neutralization of FGF2 in the CM of CAFs, CM was pre-incubated with 25 μg/mL of human FGF2 antibody or its IgG control (R&D Systems, Inc., Minneapolis, MN, USA) for 1 hour at room temperature prior to use.

Techniques: Cell Culture, Incubation, Staining, Western Blot, Marker, Immunoprecipitation, Binding Assay

Journal: Journal of Cancer Prevention

Article Title: Nuclear Localization of Fibroblast Growth Factor Receptor 1 in Breast Cancer Cells Interacting with Cancer Associated Fibroblasts

doi: 10.15430/jcp.2022.27.1.68

Figure Lengend Snippet: Figure 4. Possible association between nuclear FGFR1 and Nrf2. (A) TNBC patient cohorts were validated based on the mean expression value of the indicated single genes (FGFR1 or NFE2L2) or as a signature of two genes together and patient survival was analyzed (n = 255). (B, C) MDA- MB-231 cells were transfected with scrambled or Nrf2 si-RNA for 24 hours. Cells were then incubated with 20 ng/mL of FGF2 for 3 hours. The mRNA (B) and protein (C) expression of cyclin D1 was assessed by RT-PCR and Western blot analyses, respectively. The expression of cyclin D1 was mea- sured by RT-PCR (B) and Western blot (C) analyses. (D) In tumor microenvironment, fibroblasts are activated to form CAFs, which secrete FGF2. CAF-derived FGF2 could induces nuclear translocation as well as de novo synthesis of FGFR1, ultimately contributing to cancer cell proliferation, mi- gration and tumor growth. While membrane bound FGFR1 may translocate to nucleus as a complex with FGF2 which has nuclear localization signal (NLS), the complex is likely rather to stimulate the intracellular signaling via FRS2α, which induces transcription of FGFR-1 gene. On the other hand, newly synthesized FGFR-1 is speculated to enter the nucleus as a complex with a cargo protein harboring NLS. FGFR-1 is translocated to the inner nuclear membrane through the nuclear pore complexes (NPCs), which is regulated by importin β. FGF2, fibroblast growth factor 2; FGFR1, FGF receptor 1; TNBC, triple negative breast cancer; HR, hazard ratio; CAFs, cancer-associated fibroblasts; ER, endoplasmic reticulum; FRS2, FGFR substrate 2; CBP, CREB-binding protein.

Article Snippet: For neutralization of FGF2 in the CM of CAFs, CM was pre-incubated with 25 μg/mL of human FGF2 antibody or its IgG control (R&D Systems, Inc., Minneapolis, MN, USA) for 1 hour at room temperature prior to use.

Techniques: Expressing, Transfection, Incubation, Reverse Transcription Polymerase Chain Reaction, Western Blot, Derivative Assay, Translocation Assay, Membrane, Synthesized, Binding Assay

Journal: The FASEB Journal

Article Title: Loss of the RNA Binding Protein HuR in Early Murine Limb Mesenchyme Does Not Affect Development but Leads to Impaired Bone Homeostasis in Adulthood

doi: 10.1096/fj.202500780RR

Figure Lengend Snippet: Effect of germline Cre recombination in HuR fl/fl mice (Elavl1 KO) through maternal inheritance of Prx1‐Cre. (A) Whole‐mount embryos at E13.5 stained with alcian blue. (B) Toluidine blue‐stained sections of E13.5 embryo forelimbs and hindlimbs. (C) Immunofluorescence detection of HuR in limb sections from E13.5 embryos. (D) Brightfield micrographs demonstrating morphology changes in Control and Elavl1 KO embryos isolated from E9.5 to E11.5. Scale bar = 500 μm. (E) Whole‐mount in situ hybridization chain reaction detection of limb bud markers mRNA in E10.5 and E11.5 embryos. Asterisk: Limb bud, Triangle: Apical ectodermal ridge, Arrowhead: The zone of polarizing activity. Scale bar = 150 μm. (F) Whole‐mount immunofluorescence detection of Fgf8 protein in E10.5 embryos. Asterisk: Limb bud, Triangle: Apical ectodermal ridge. Scale bar = 150 μm.

Article Snippet: Embryos were fixed in 4% formaldehyde for 1 h at 4°C, washed, and stored in 0.0025% Triton X‐100 in PBS (PBS‐Tr) at 4° C. Prior to immunofluorescence staining, embryos were permeabilized with 0.25% Triton X‐100 in PBS for 30 min and then blocked with 2% bovine serum albumin in PBS solution for 1 h before incubation with 1:100 Fgf8 antibody (MAB323, R&D Systems, UK) overnight at 4°C.

Techniques: Staining, Immunofluorescence, Control, Isolation, In Situ Hybridization, Activity Assay