Journal: BMC Cancer

Article Title: FAT4 silencing promotes epithelial-to-mesenchymal transition and invasion via regulation of YAP and β-catenin activity in ovarian cancer

doi: 10.1186/s12885-020-06900-7

Figure Lengend Snippet: Pearson’s correlation between different gene expressions using samples from GEPIA database. a . FAT4 and E2F5 is negatively correlated ( p = 3.3e − 11 , r = − 0.29). b . Cyclin D1 expression was negatively correlated with FAT4 ( p = 3e − 6 , r = − 0.2). c . Pearson’s correlation demonstrating negative correlation between cdk4 and FAT4 ( p = 1.1e − 6 , r = − 0.21). d. FAT4 was positively correlated with caspase 9 ( p < 0.05, r = 0.56)

Article Snippet: Total RNA was extracted from the ovarian cancer cell lines using PureLink RNA mini kit (Invitrogen, CA, USA) according to the manufacturer’s protocol, and subsequently reverse transcribed to complementary DNA using high capacity reverse transcription kit (Invitrogen, CA, USA). qRT-PCR was performed using TaqMan pre-optimized probes ( FAT4 : Catalogue No. Hs01570499_m1, E2F5 : Catalogue No.Hs00231092_m1, GAPDH : Catalogue No. 402869; Thermo Scientific Fisher, USA) and run on ABI 7500 Fast real-time PCR machine (Applied Biosystems, Austin, TX).

Techniques: Expressing

Journal: BMC Cancer

Article Title: FAT4 silencing promotes epithelial-to-mesenchymal transition and invasion via regulation of YAP and β-catenin activity in ovarian cancer

doi: 10.1186/s12885-020-06900-7

Figure Lengend Snippet: a . FAT4 knockdown upregulated the expression of E2F5 suggesting a link between the two genes. b . A suggested mechanism of EMT and cell cycle regulation by FAT4 based on Western blot obtained data. Inhibition of FAT4 regulates the expression of EMT markers and promotes cell cycle progression via the suggested pathway. The solid lines indicate the results obtained from the previous study , while the dotted lines indicate results of our western blotting experiments

Article Snippet: Total RNA was extracted from the ovarian cancer cell lines using PureLink RNA mini kit (Invitrogen, CA, USA) according to the manufacturer’s protocol, and subsequently reverse transcribed to complementary DNA using high capacity reverse transcription kit (Invitrogen, CA, USA). qRT-PCR was performed using TaqMan pre-optimized probes ( FAT4 : Catalogue No. Hs01570499_m1, E2F5 : Catalogue No.Hs00231092_m1, GAPDH : Catalogue No. 402869; Thermo Scientific Fisher, USA) and run on ABI 7500 Fast real-time PCR machine (Applied Biosystems, Austin, TX).

Techniques: Knockdown, Expressing, Western Blot, Inhibition

Journal: Journal of Translational Medicine

Article Title: Exosomes loaded with the anti-cancer molecule mir-1-3p inhibit intrapulmonary colonization and growth of human esophageal squamous carcinoma cells

doi: 10.1186/s12967-024-05997-9

Figure Lengend Snippet: miR-1-3p directly targets and down-regulates E2F5 expression. The differentially expressed genes in the Exo-miR-1-3p group compared with the Exo-NC group, shown in the volcano plot ( A ), and the KEGG pathway analysis of differentially expressed genes ( B ). ( C ) Predicted target genes of miR-1-3p with TargetScan and miRWalk were cross-analyzed with significantly expression down-regulated genes. ( D ) E2F5 mRNA level after Exo-miR-1-3p incubation. ( E ) Putative binding sequence of miR-1-3p to the E2F5 mRNA 3’UTR and results of dual luciferase reporter assays. E2F5 protein expression of KYSE150 and Eca109 cells transfected with miR-1-3p mimics ( F ) or miR-1-3p inhibitor ( G ). Immunohistochemical staining ( H ) and H-scores ( I ) of E2F5 in mouse lung tissues. * P < 0.05, *** P < 0.001

Article Snippet: Antibodies information used in this study is provided below: anti-TSG101 (1:2000, 14497-1-AP, Proteintech), anti-CD81 (66866-1-Ig), anti-CD9 (60232-1-Ig), anti-E2F5 (1:2000, bs-1734R, Bioss), anti-GAPDH (1:5000, 60004-1-Ig, Proteintech), anti-p-p38 (1:1000, 4511, CST), anti-p38 (1:5000, 66234-1-lg, Proteintech), anti-p-ERK (1:1000, AP0974, ABclonal), anti-ERK (1:700, A4782, ABclonal), anti-p-Akt (1:2000, 28731-1-AP, Proteintech), anti-p-mTOR (1:500, AF3308, Affinity), HRP Goat anti-Rabbit IgG (1: 5000, AS014, ABclonal), HRP Goat anti-Mouse IgG (1: 5000, AS003, ABclonal).

Techniques: Expressing, Incubation, Binding Assay, Sequencing, Luciferase, Transfection, Immunohistochemical staining, Staining

Journal: Journal of Translational Medicine

Article Title: Exosomes loaded with the anti-cancer molecule mir-1-3p inhibit intrapulmonary colonization and growth of human esophageal squamous carcinoma cells

doi: 10.1186/s12967-024-05997-9

Figure Lengend Snippet: miR-1-3p inhibits proliferation and migration of ESCC cells in vitro by down-regulating E2F5. The miR-1-3p levels ( A ), E2F5 mRNA levels ( B ), and E2F5 protein levels in KYSE150 and Eca109 cells in vitro co-transfected with miR-1-3p mimics and E2F5 expression plasmids. The proliferation ( D ) and migration ( E and F ) of transfected cells. ns, no significance; * P < 0.05, *** P < 0.001

Article Snippet: Antibodies information used in this study is provided below: anti-TSG101 (1:2000, 14497-1-AP, Proteintech), anti-CD81 (66866-1-Ig), anti-CD9 (60232-1-Ig), anti-E2F5 (1:2000, bs-1734R, Bioss), anti-GAPDH (1:5000, 60004-1-Ig, Proteintech), anti-p-p38 (1:1000, 4511, CST), anti-p38 (1:5000, 66234-1-lg, Proteintech), anti-p-ERK (1:1000, AP0974, ABclonal), anti-ERK (1:700, A4782, ABclonal), anti-p-Akt (1:2000, 28731-1-AP, Proteintech), anti-p-mTOR (1:500, AF3308, Affinity), HRP Goat anti-Rabbit IgG (1: 5000, AS014, ABclonal), HRP Goat anti-Mouse IgG (1: 5000, AS003, ABclonal).

Techniques: Migration, In Vitro, Transfection, Expressing

Journal: Journal of Translational Medicine

Article Title: Exosomes loaded with the anti-cancer molecule mir-1-3p inhibit intrapulmonary colonization and growth of human esophageal squamous carcinoma cells

doi: 10.1186/s12967-024-05997-9

Figure Lengend Snippet: miR-1-3p inhibits invasion of ESCC cells in vitro by down-regulating E2F5, which may involve the MAPK/ERK signaling pathway. ( A and B ) The invasion of KYSE150 and Eca109 cells in vitro co-transfected with miR-1-3p mimics and E2F5 expression plasmids. ( C ) The protein levels of p-p38, p38, p-ERK, ERK in transfected cells, detected with western blot. ns, no significance; *** P < 0.001

Article Snippet: Antibodies information used in this study is provided below: anti-TSG101 (1:2000, 14497-1-AP, Proteintech), anti-CD81 (66866-1-Ig), anti-CD9 (60232-1-Ig), anti-E2F5 (1:2000, bs-1734R, Bioss), anti-GAPDH (1:5000, 60004-1-Ig, Proteintech), anti-p-p38 (1:1000, 4511, CST), anti-p38 (1:5000, 66234-1-lg, Proteintech), anti-p-ERK (1:1000, AP0974, ABclonal), anti-ERK (1:700, A4782, ABclonal), anti-p-Akt (1:2000, 28731-1-AP, Proteintech), anti-p-mTOR (1:500, AF3308, Affinity), HRP Goat anti-Rabbit IgG (1: 5000, AS014, ABclonal), HRP Goat anti-Mouse IgG (1: 5000, AS003, ABclonal).

Techniques: In Vitro, Transfection, Expressing, Western Blot

Journal:

Article Title: Analysis of promoter binding by the E2F and pRB families in vivo: distinct E2F proteins mediate activation and repression

doi:

Figure Lengend Snippet: In vivo detection of promoter occupancy by the E2F and pRB family using chromatin immunoprecipitations. (A) Outline of the in vivo cross-linking and chromatin immunoprecipitation (IP) protocol. (B) Promoters examined in this study. Solid ovals represent E2F-binding sites on the basis of previous studies; small arrows indicate primers used in PCR amplification reactions. Large arrows represent published major transcription start site. (C) Chromatin immunoprecipitations from asynchronously growing T98G cells. Input corresponds to PCR reactions containing 0.5% of total amount of chromatin used in immunoprecipitation reactions. Mock immunoprecipitations performed with irrelevant, control antibodies (anti-T Antigen pAb101) and control reactions lacking antibodies (No Ab) are shown. Amplified products were detected by autoradiography.

Article Snippet: Antibodies that recognize E2F-1 (sc-193), E2F-2 (sc-633x), E2F-3 (sc-878x), E2F-4 (sc-1082x), E2F-5 (sc-999, sc-968), p107 (sc-318), pRB (sc-50, G99-549, G3-245), p130 (sc-317, Rb2), cdk2 (sc-163), and 12CA5 anti-flu hemagglutinin were obtained from Santa Cruz Biotechnology, Neomarkers, Pharmingen, Transduction Labs, and BabCo.

Techniques: In Vivo, Chromatin Immunoprecipitation, Binding Assay, Amplification, Immunoprecipitation, Autoradiography

Journal:

Article Title: Analysis of promoter binding by the E2F and pRB families in vivo: distinct E2F proteins mediate activation and repression

doi:

Figure Lengend Snippet: Cell cycle synchronization and gene expression analysis. (A) FACS analysis of T98G cells that were rendered quiescent by serum starvation (0 hr) and were subsequently restimulated with serum for the indicated lengths of time and allowed to enter the cell cycle. DNA content (propidium iodide intensity) is plotted vs. cell number. (B) Northern blot analysis of expression of the indicated genes during the synchronization experiment in A. To ensure equal loading of RNA, each blot was subsequently stripped and rehybridized with an ARPP P0 gene fragment, and a representative filter is shown. (C) Gel mobility shift analysis of E2F and pRB complexes. Whole cell extracts at each stage of the cell cycle (indicated at top) were incubated with a labeled probe containing an E2F site and each of the designated antibodies. The positions of E2F-pRB/p107/p130 complexes and free E2F (E2F) are shown at right. Each of these complexes was abrogated by a specific competitor oligonucleotide (data not shown). Asynchronous (AS) samples were prepared from cells entering a second cell cycle (with roughly equal percentages of G1, S, and G2 cells). Lanes marked − and control contained no antibody and 12CA5 (anti-flu hemagglutinin antibody), respectively. α-E2F-4 lanes contain two different monoclonal antibodies specific for E2F-4 (WUF3 and LLF4, respectively).

Article Snippet: Antibodies that recognize E2F-1 (sc-193), E2F-2 (sc-633x), E2F-3 (sc-878x), E2F-4 (sc-1082x), E2F-5 (sc-999, sc-968), p107 (sc-318), pRB (sc-50, G99-549, G3-245), p130 (sc-317, Rb2), cdk2 (sc-163), and 12CA5 anti-flu hemagglutinin were obtained from Santa Cruz Biotechnology, Neomarkers, Pharmingen, Transduction Labs, and BabCo.

Techniques: Expressing, Northern Blot, Mobility Shift, Incubation, Labeling

Journal:

Article Title: Analysis of promoter binding by the E2F and pRB families in vivo: distinct E2F proteins mediate activation and repression

doi:

Figure Lengend Snippet: The binding of E2F family of proteins changes during the cell cycle. Chromatin immunoprecipitations were performed with antibodies specific for individual E2F family members as indicated, and the resulting immunoprecipitates were amplified with primer pairs corresponding to the genes shown. G0, serum-starved cells; early G1, late G1, G1/S, and S-phase cells were stimulated with serum 4–8, 16, 20, and 24 hr, respectively. Antibodies tested in each case are listed in Materials and Methods.

Article Snippet: Antibodies that recognize E2F-1 (sc-193), E2F-2 (sc-633x), E2F-3 (sc-878x), E2F-4 (sc-1082x), E2F-5 (sc-999, sc-968), p107 (sc-318), pRB (sc-50, G99-549, G3-245), p130 (sc-317, Rb2), cdk2 (sc-163), and 12CA5 anti-flu hemagglutinin were obtained from Santa Cruz Biotechnology, Neomarkers, Pharmingen, Transduction Labs, and BabCo.

Techniques: Binding Assay, Amplification

Journal:

Article Title: Analysis of promoter binding by the E2F and pRB families in vivo: distinct E2F proteins mediate activation and repression

doi:

Figure Lengend Snippet: Antibodies against each pRB family member immunoprecipitate their chromatin-bound targets. (A) Schematic representing the position of chromatin in gradients relative to free DNA and protein under conditions in which cells were either fixed with formaldehyde (+ cross-linker) or left untreated (− cross-linker). Brackets indicate chromatin fractions selected for further analysis in B. (B) Fractions in A were immunoprecipitated with anti-pRB, anti-p107, and p130 antibodies as indicated and the resulting precipitates were probed with the same antibodies as indicated. (C) p107 and p130 are detected at similar levels in T98G cells entering a second cell cycle (32-hr time point in Fig. ​Fig.2).2). Chromatin immunoprecipitations were performed with the indicated antibodies, and E2F-1, cyclin A, and actin promoter fragments were amplified as described in the legend to Fig. ​Fig.1.1. Distinct monoclonal and polyclonal anti-pRB antibodies were tested as shown.

Article Snippet: Antibodies that recognize E2F-1 (sc-193), E2F-2 (sc-633x), E2F-3 (sc-878x), E2F-4 (sc-1082x), E2F-5 (sc-999, sc-968), p107 (sc-318), pRB (sc-50, G99-549, G3-245), p130 (sc-317, Rb2), cdk2 (sc-163), and 12CA5 anti-flu hemagglutinin were obtained from Santa Cruz Biotechnology, Neomarkers, Pharmingen, Transduction Labs, and BabCo.

Techniques: Immunoprecipitation, Amplification

Journal:

Article Title: Analysis of promoter binding by the E2F and pRB families in vivo: distinct E2F proteins mediate activation and repression

doi:

Figure Lengend Snippet: Histone acetylation levels of E2F-responsive genes change during the cell cycle. (A) Chromatin was prepared from synchronized T98G cells (as described in Fig. ​Fig.2A)2A) and immunoprecipitated with antibodies specific for acetylated histone H3 and acetylated H4 as described in the legend to Fig. ​Fig.1.1. Cell cycle stages were identical to those described in Fig. ​Fig.3.3. Parallel immunoprecipitations without antibody or with an irrelevant antibody control failed to yield detectable signals after an equivalent autoradiographic exposure (data not shown). (B) Data in A were quantitated by PhosphorImager analysis and normalized vs. input levels. The y-axis indicates fold acetylation (in arbitrary units). (Light-colored bars) acetylated H3; (dark bars) acetylated H4.

Article Snippet: Antibodies that recognize E2F-1 (sc-193), E2F-2 (sc-633x), E2F-3 (sc-878x), E2F-4 (sc-1082x), E2F-5 (sc-999, sc-968), p107 (sc-318), pRB (sc-50, G99-549, G3-245), p130 (sc-317, Rb2), cdk2 (sc-163), and 12CA5 anti-flu hemagglutinin were obtained from Santa Cruz Biotechnology, Neomarkers, Pharmingen, Transduction Labs, and BabCo.

Techniques: Immunoprecipitation

Journal:

Article Title: Analysis of promoter binding by the E2F and pRB families in vivo: distinct E2F proteins mediate activation and repression

doi:

Figure Lengend Snippet: Model for in vivo occupancy by E2F and pRB family members during cell cycle progression. (A) In vivo occupation of E2F-1, Cdc25A, cyclin A, Cdc6, and p107 promoters by the E2F and pRB family during cell cycle progression and transcriptional consequences. (B) In vivo binding of B-myb promoter. In A and B, promoter binding by E2F-4 correlates with transcriptional repression, whereas binding by E2F-1 and E2F-3 occurs at a time when each promoter is activated. However, the B-myb promoter is transcriptionally active after E2F is no longer bound, consistent with Zwicker et al. (1996). (D) HDAC activity; (H) nucleosomes; (Ac) acetylated histones; (HAT) histone acetyltransferase. These promoters are likely to be regulated by additional trans-activator proteins proximal to E2F, including Sp1. Recruitment of deacetylase and HAT activities could occur by direct interactions with E2F complexes or could require additional factors (X) yet to be defined.

Article Snippet: Antibodies that recognize E2F-1 (sc-193), E2F-2 (sc-633x), E2F-3 (sc-878x), E2F-4 (sc-1082x), E2F-5 (sc-999, sc-968), p107 (sc-318), pRB (sc-50, G99-549, G3-245), p130 (sc-317, Rb2), cdk2 (sc-163), and 12CA5 anti-flu hemagglutinin were obtained from Santa Cruz Biotechnology, Neomarkers, Pharmingen, Transduction Labs, and BabCo.

Techniques: In Vivo, Binding Assay, Activity Assay, Histone Deacetylase Assay

Journal: Nucleic Acids Research

Article Title: The p21CIP1-CDK4-DREAM axis is a master regulator of genotoxic stress-induced cellular senescence

doi: 10.1093/nar/gkae426

Figure Lengend Snippet: MCF7 cells were exposed to 1 μM B[a]P ( A, C ) or 5 Gy IR ( B, D ). Expression of E2F1, E2F4, E2F5, CCNA1, CCNA2, CCNB1, CCNB2, CCND1 and CCND2 was analysed by qPCR (A, B). ACTB and GAPDH were used as internal loading control, differences between treatment and control were statistically analysed using Student's t test (non labelled = non significant, * P < 0.1 ** P < 0.01, *** P < 0.001). Expression of E2F4, pRB, RB, pp130 and p130 was analysed by immunodetection (C, D). β-Actin or HSP90 were used as internal loading control, quantification of band intensities from two blots is shown.

Article Snippet: For gene silencing, predesigned siRNAs specific for p16 INK4A (sc-37622, Santa Cruz Biotechnology), p21 CIP1 (sc-29427, Santa Cruz Biotechnology), E2F4 (sc-29300, Santa Cruz Biotechnology) and E2F5 (sc-35250, Santa Cruz Biotechnology) were used; control human non-silencing siRNA (Silencer Select Predesigned siRNA Negative Control #1 siRNA; Ambion) was used as negative control.

Techniques: Expressing, Control, Immunodetection

Journal: Nucleic Acids Research

Article Title: The p21CIP1-CDK4-DREAM axis is a master regulator of genotoxic stress-induced cellular senescence

doi: 10.1093/nar/gkae426

Figure Lengend Snippet: ( A ) Expression of E2F4 and E2F5 was detected 48 and 72 h after siRNA-mediated knockdown by immunodetection; β-Actin was used as internal loading control; quantification of band intensities indicates knock-down efficiency. ( B, C ) MCF7 cells were treated with E2F4-, E2F5- or non-specific siRNA for 24 h and thereafter exposed to B[a]P or IR for 120 h. ( B ) Senescence was measured microscopically by β-Gal staining. ( C ) Expression of CDK1, FOXM1, MYBL2, HMGB2, CCNB1, LMNB1, PLK1, CENPF, TK1 and ASPM was measured by qPCR; ACTB and GAPDH were used as internal loading control. (B, C) Experiments were performed in triplicates, differences between treatment in absence or presence of siRNA were statistically analysed using Student's t test (non labelled = non significant, * P < 0.1 ** P < 0.01, *** P < 0.001).

Article Snippet: For gene silencing, predesigned siRNAs specific for p16 INK4A (sc-37622, Santa Cruz Biotechnology), p21 CIP1 (sc-29427, Santa Cruz Biotechnology), E2F4 (sc-29300, Santa Cruz Biotechnology) and E2F5 (sc-35250, Santa Cruz Biotechnology) were used; control human non-silencing siRNA (Silencer Select Predesigned siRNA Negative Control #1 siRNA; Ambion) was used as negative control.

Techniques: Expressing, Knockdown, Immunodetection, Control, Staining

Journal: Journal of Biological Chemistry

Article Title: The Cancer/Testis Antigen CAGE with Oncogenic Potential Stimulates Cell Proliferation by Up-regulating Cyclins D1 and E in an AP-1- and E2F-dependent Manner

doi: 10.1074/jbc.m109.084400

Figure Lengend Snippet: FIGURE6.LevelsofAP-1proteins,Rbphosphorylation,andnuclearE2Fin CAGE-overexpressing cells. A, protein levels of Jun and Fos subfamily mem- bers of AP-1 factors were examined in tetracycline-inducible CAGE transfec- tant HeLa cells by immunoblotting analysis after doxycycline (dox) treatment for 8 h. The phosphorylation level of c-Jun was evaluated by using an anti- body specific to the phospho-Ser-63/Ser-73 residues of c-Jun. B, CAGE trans- fectant clonal cells (#2-27) were treated with or without doxycycline for the indicated time periods, and E2F-1 protein levels in the total cell lysate, the cytosolic and nuclear fractions, and the Rb immunoprecipitate (IP) were examined for by immunoblotting analysis. C, the phosphorylation level of Rb in cells (#2-27) treated with or without doxycycline was assessed by immuno- blotting analysis using an antibody specific to Rb phosphorylated at the Ser- 795 residue.

Article Snippet: A double-stranded oligonucleotide containing the consensus binding motif of E2F (5 -ATTTAAGTTTCGCGCCCTTTCTCAA-3 ; the E2F consensus recognition sequence is underlined) was obtained from Santa Cruz Biotechnology.

Techniques: Western Blot, Phospho-proteomics, Residue

Journal: Journal of Biological Chemistry

Article Title: The Cancer/Testis Antigen CAGE with Oncogenic Potential Stimulates Cell Proliferation by Up-regulating Cyclins D1 and E in an AP-1- and E2F-dependent Manner

doi: 10.1074/jbc.m109.084400

Figure Lengend Snippet: FIGURE 7. Ablation of CAGE-induced G1 cyclin expression by an inhibitor of JNK and siRNAs for JunD and E2F-1. A, the tetracycline-inducible CAGE transfectant clone (#2-27) of HeLa cells was pretreated with a JNK inhibitor, SP600125, for 4 h and further incubated in the absence or presence of doxy- cycline (dox) for 8 h. The levels of cyclin D1 and E proteins, phospho-c-Jun, phospho-Rb, and cytosolic and nuclear E2F-1 proteins were assessed by immunoblotting analysis. B and C, the clonal cells (#2-27) were transfected with control and JunD (B) or E2F-1 (C) siRNAs. At 48 hours after transfection, cellsweretreatedwithorwithoutdoxycyclinefor8handanalyzedforprotein levels of cyclins D1 and E.

Article Snippet: A double-stranded oligonucleotide containing the consensus binding motif of E2F (5 -ATTTAAGTTTCGCGCCCTTTCTCAA-3 ; the E2F consensus recognition sequence is underlined) was obtained from Santa Cruz Biotechnology.

Techniques: Expressing, Transfection, Incubation, Western Blot, Control

Journal: Journal of Biological Chemistry

Article Title: The Cancer/Testis Antigen CAGE with Oncogenic Potential Stimulates Cell Proliferation by Up-regulating Cyclins D1 and E in an AP-1- and E2F-dependent Manner

doi: 10.1074/jbc.m109.084400

Figure Lengend Snippet: FIGURE 8. CAGE siRNA-mediated suppression of G1 cyclin expression, Jun AP-1 protein expression/acti- vation, E2F-1 nuclear translocation, and cell proliferation in human cancer cell lines. A and B, protein levels of CAGE, cyclins D1 and E, and JunD and the phosphorylation level of c-Jun (A) and Rb (B) were deter- mined in CAGE siRNA-transfected HeLa and Malme-3M cells. Cont, control. C, the level of cytosolic and nuclear E2F-1 was assessed by immunoblotting analysis after subcellular fractionation. D and E, cell proliferation was measured by MTS assay upon siRNA knockdown of CAGE in HeLa and Malme-3M cells as described under “Experimental Procedures.” *, p 0.01 versus doxycycline at day 4 in culture.

Article Snippet: A double-stranded oligonucleotide containing the consensus binding motif of E2F (5 -ATTTAAGTTTCGCGCCCTTTCTCAA-3 ; the E2F consensus recognition sequence is underlined) was obtained from Santa Cruz Biotechnology.

Techniques: Expressing, Translocation Assay, Phospho-proteomics, Transfection, Control, Western Blot, Fractionation, MTS Assay, Knockdown