Journal: bioRxiv

Article Title: RBN-2397, a PARP7 Inhibitor, Synergizes with Paclitaxel to Inhibit Proliferation and Migration of Ovarian Cancer Cells

doi: 10.1101/2024.08.20.608802

Figure Lengend Snippet: (A and B) Dose response curves showing increasing concentrations of RBN-2397 (A) or paclitaxel (B) significantly decreasing cell viability in ovarian cancer cells (OVCAR4 and OVCAR3), assayed by crystal violet staining. IC50s were calculated; Paclitaxel: 0.47 nM (OVCAR4), 0.46 nM (OVCAR3); RBN-2397: 727.2 nM (OVCAR4), 1159 nM (OVCAR3). Points marked with asterisks are significantly different; Student’s t-test; *** = p<0.001, **** = p<0.0001. (C and D) Line graphs showing the growth of OVCAR4 cells (C) and OVCAR3 cells (D) over a period of 6 days with different conditions: DMSO, RBN-2397 (500 nM), paclitaxel (0.4 nM), combination ( left panels ). Each point represents the mean ± SEM; n=3. Points marked with asterisks are significantly different; Student’s t-test; ** = p<0.01. Bar graphs showing quantification of the proliferation assays at Day 6 ( right panels ). Each bar represents the mean ± SEM; n=3. Bars marked with different letters are significantly different, Ordinary one-way ANOVA test.

Article Snippet: OVCAR3 and OVCAR4 serous ovarian cancer cell lines were purchased from the American Type Culture Collection (OVCAR3: ATCC; RRID: CVCL_0465, OVCAR4: ATCC; RRID: CVCL_1627).

Techniques: Staining

Journal: bioRxiv

Article Title: RBN-2397, a PARP7 Inhibitor, Synergizes with Paclitaxel to Inhibit Proliferation and Migration of Ovarian Cancer Cells

doi: 10.1101/2024.08.20.608802

Figure Lengend Snippet: (A) Representative images of cell migration assays for OVCAR4 cells treated with DMSO, RBN-2397 (500 nM), paclitaxel (0.4 nM), and combination. (B) Quantification of the cell migration assays shown in (A) for OVCAR4 cells. Each bar represents the mean ± SEM; n=3. Bars marked with different letters are significantly different, Ordinary one-way ANOVA test.

Article Snippet: OVCAR3 and OVCAR4 serous ovarian cancer cell lines were purchased from the American Type Culture Collection (OVCAR3: ATCC; RRID: CVCL_0465, OVCAR4: ATCC; RRID: CVCL_1627).

Techniques: Migration

Journal: bioRxiv

Article Title: RBN-2397, a PARP7 Inhibitor, Synergizes with Paclitaxel to Inhibit Proliferation and Migration of Ovarian Cancer Cells

doi: 10.1101/2024.08.20.608802

Figure Lengend Snippet: (A) RBN-2397 blocks the autoMARylation of ectopically expressed FLAG-PARP7 in OVCAR4 cells, assayed by immunoprecipitation of FLAG followed by Western blot for MAR. (B) RBN-2397 blocks the MARylation of α-tubulin in OVCAR4 cells, even in the presence of paclitaxel, assayed by immunoprecipitation of MAR followed by Western blot for α -tubulin. (C) Stabilization of endogenous PARP7 levels were detected in OVCAR4 cells following treatment with RBN-2397 (1 μM) alone and in combination with paclitaxel (1 nM), assayed by Western blot. (D) Bar graph showing quantification of PARP7 levels from experiments shown in panel (C) for OVCAR4 cells. Each bar represents the mean ± SEM; n=3. Bars marked with different letters are significantly different, Ordinary one-way ANOVA test.

Article Snippet: OVCAR3 and OVCAR4 serous ovarian cancer cell lines were purchased from the American Type Culture Collection (OVCAR3: ATCC; RRID: CVCL_0465, OVCAR4: ATCC; RRID: CVCL_1627).

Techniques: Immunoprecipitation, Western Blot

Journal: bioRxiv

Article Title: RBN-2397, a PARP7 Inhibitor, Synergizes with Paclitaxel to Inhibit Proliferation and Migration of Ovarian Cancer Cells

doi: 10.1101/2024.08.20.608802

Figure Lengend Snippet: (A) RBN-2397, paclitaxel, and their combination promote microtubule stability in OVCAR4 cells. Representative immunofluorescent images of α-tubulin in OVCAR4 cells after treatment with DMSO, RBN-2397 (500 nM), paclitaxel (0.4 nM), or their combination and exposure to cold treatment or nocodazole. The experiment was performed 3 times to ensure reproducibility. Scale bar = 12.5 μm. (B) Violin plots quantifying α-tubulin staining from experiments shown in (A) in OVCAR4 cells untreated (left panel) , cold (middle panel) , or nocodazole treated (right panel) . Violins marked with different letters are significantly different, Ordinary one-way ANOVA test; n=3.

Article Snippet: OVCAR3 and OVCAR4 serous ovarian cancer cell lines were purchased from the American Type Culture Collection (OVCAR3: ATCC; RRID: CVCL_0465, OVCAR4: ATCC; RRID: CVCL_1627).

Techniques: Staining

Journal: bioRxiv

Article Title: RBN-2397, a PARP7 Inhibitor, Synergizes with Paclitaxel to Inhibit Proliferation and Migration of Ovarian Cancer Cells

doi: 10.1101/2024.08.20.608802

Figure Lengend Snippet: (A) Wild-type (WT) and MARylation-site mutant α-tubulin (Mut) are expressed at similar levels in the wild-type and mutant OVCAR4 cell lines, assayed by Western blot. (B) Representative immunofluorescent images of α-tubulin showing increased microtubule stability in Mut compared to WT; paclitaxel (1 nM) enhances microtubule stability in both mutant and WT after cold exposure. The experiment was performed 3 times to ensure reproducibility. Scale bar = 25 μm. (C) Violin plots quantifying α-tubulin staining from experiments shown in (B) in untreated (left panel) and cold treated cells (right panel) . Violins marked with different letters are significantly different, Ordinary one-way ANOVA test; n=3. (D and E) Cell migration assays for OVCAR4 WT and α-tubulin mutant with DMSO and paclitaxel (1 nM). Bar plot showing quantification of the cell migration assays shown in (D). Each bar represents the mean ± SEM; n=3. Bars marked with different letters are significantly different, Ordinary one-way ANOVA test.

Article Snippet: OVCAR3 and OVCAR4 serous ovarian cancer cell lines were purchased from the American Type Culture Collection (OVCAR3: ATCC; RRID: CVCL_0465, OVCAR4: ATCC; RRID: CVCL_1627).

Techniques: Mutagenesis, Western Blot, Staining, Migration

Journal: Molecular Oncology

Article Title: Plasma membrane SK2 channel activity regulates migration and chemosensitivity of high‐grade serous ovarian cancer cells

doi: 10.1002/1878-0261.13631

Figure Lengend Snippet: SK2 channels contribute in store‐operated calcium entry (SOCE) and migration in high‐grade serous ovarian cancer (HGSOC) cells. (A) Effect of Lei‐Dab‐7 on current–density amplitude of COV504 cells. Lei‐Dab7 sensitive current–density–voltage relationships during voltage step cells before and after Lei‐Dab7 (10 n m ) perfusion ( N = 8). Sensitive current was obtained by subtracting the outward current recorded in the presence of Lei‐Dab7 from the net outward current observed in normal physiological saline solution (left panel). Current density measured at +30 mV (right panel). (B) SOCE measurements in COV504 (left panel) ( n = 12, N = 5) or OVCAR3 cells (right panel) ( n = 17, N = 5) using Fura‐2‐AM with or without acute Lei‐Dab7 administration. (C and D) Transwell migration assay with cells treated or not with Lei‐Dab7 (left panels) (COV504, N4; OVCAR3, N = 7) or siSK2 (right panels) (COV504, N = 8; OVCAR3, N = 4). (E) Plasma membrane and intracellular SK2 channel pools that contribute to cell migration and SOCE in HGSOC. The cell migration (C and D) and the Ca 2+ measurement amplitudes (B) were expressed as mean ± SEM, each point is the result of one experiment, and is normalized to the control condition (Mann–Whitney, P < 0.05*, P < 0.01**, P < 0.001***). The whole cell recording results (A) are represented as mean ± SEM (Wilcoxon, P < 0.01**) (Tg, Thapsigargin).

Article Snippet: Human high‐grade serous ovarian cancer cell lines COV504 and OVCAR3 were maintained, respectively, in DMEM and RPMI 1640 medium (Gibco, Illkirch, France) supplemented with 10% fetal bovine serum (FBS, Hyclone Lonza Bioscience, Illkirch, France) under 5% CO 2 at 37 °C.

Techniques: Migration, Saline, Transwell Migration Assay, Membrane, Control, MANN-WHITNEY

Journal: Molecular Oncology

Article Title: Plasma membrane SK2 channel activity regulates migration and chemosensitivity of high‐grade serous ovarian cancer cells

doi: 10.1002/1878-0261.13631

Figure Lengend Snippet: LPA increases the activity of plasma membrane SK2 and cell migration in a store‐operated calcium entry (SOCE) independent manner. (A) Effect of LPA pre‐treatment on SK2 current. Current density–voltage relationships obtained on COV504 cells before and after LPA treatment (10 μ m ) for 72 h and with or without acute Lei‐Dab7 application (10 n m ) (PSS Control, N = 6; LPA, N = 14; LPA + Lei‐Dab7, N = 6) (A). Current‐density measured at +30 mV (B) and evaluation of membrane potential (Em) on COV504 cells control and pre‐treated with LPA ± Lei‐Dab7 (C). (B) KCNN2 mRNA (left panel) and SK2 protein (right panel) expression level quantified by qRT‐PCR ( N = 4) and western blot ( N = 4), respectively. Measurements were performed on COV504 cells with or without LPA pre‐treatment (10 μ m ). (C) SOCE measurements in COV504 cells ( n = 16, N = 4) using Fura‐2‐AM fluorescent probe with or without acute Lei‐Dab7 application (10 n m ) on cells, in the presence or absence of LPA for 72 h (10 μ m ). (D) Transwell migration assay with COV504 (left panel) ( N = 5) or OVCAR3 (right panel) ( N = 7) cells with or without Lei‐Dab7 (10 n m ) or LPA pre‐treatment (72 h, 10 μ m ) for 24 h assay. (E) Hypothetical representation of LPA activity that induces SK2‐dependent cell migration but loss of SK2 channel participation in SOCE in HGSOC cells. Whole cell recording (A) is expressed as mean ± SEM (Wilcoxon, P < 0.05*, P < 0.01**, P < 0.001***). Results from qRT‐PCR (B, left panel), western blots (B, right panel), Ca 2+ measurements (C), and migration assay (D) are expressed as mean ± SEM, each point is the result of one experiment, and is normalized to the control condition (Mann–Whitney, P < 0.05*, P < 0.01** (B), One‐way ANOVA, P < 0.05*, P < 0.01** (C, D)) (LPA, lysophosphatidic acid; Tg, Thapsigargin).

Article Snippet: Human high‐grade serous ovarian cancer cell lines COV504 and OVCAR3 were maintained, respectively, in DMEM and RPMI 1640 medium (Gibco, Illkirch, France) supplemented with 10% fetal bovine serum (FBS, Hyclone Lonza Bioscience, Illkirch, France) under 5% CO 2 at 37 °C.

Techniques: Activity Assay, Membrane, Migration, Control, Expressing, Quantitative RT-PCR, Western Blot, Transwell Migration Assay, MANN-WHITNEY

Journal: Molecular Oncology

Article Title: Plasma membrane SK2 channel activity regulates migration and chemosensitivity of high‐grade serous ovarian cancer cells

doi: 10.1002/1878-0261.13631

Figure Lengend Snippet: Plasma membrane SK2 activity increases Taxol® sensitivity in sensitive and resistant cell lines. In the presence or absence of Lei‐Dab7 (10 n m ), cells were treated with a range of Taxol® concentration to evaluate EC 50 values in a 7‐day survival assay in OVCAR3 ( N = 8) (A), and COV504 ( N = 6) (B), OVCAR3 TX ( N = 5) (C), and COV504 TX ( N = 6) (D) cells. EC 50 is the dose for which we obtained 50% of the drug's maximal effect. EC 50 increase is associated with drug resistance. On the right, histograms represent EC 50 values in the presence of Lei‐Dab7. Each point is the result of one experiment. For the statistical analysis of EC 50 in OVCAR3 TX + Lei‐Dab7 condition, the maximal value of the Taxol® range was used (40 n m ) (representing by a dot line on C right panel). The survival assay results are expressed as mean ± SEM (Wilcoxon, P < 0.05*) (OVCAR3 TX and COV504 TX = Taxol® resistant cells).

Article Snippet: Human high‐grade serous ovarian cancer cell lines COV504 and OVCAR3 were maintained, respectively, in DMEM and RPMI 1640 medium (Gibco, Illkirch, France) supplemented with 10% fetal bovine serum (FBS, Hyclone Lonza Bioscience, Illkirch, France) under 5% CO 2 at 37 °C.

Techniques: Membrane, Activity Assay, Concentration Assay, Clonogenic Cell Survival Assay

Journal: Molecular Oncology

Article Title: Plasma membrane SK2 channel activity regulates migration and chemosensitivity of high‐grade serous ovarian cancer cells

doi: 10.1002/1878-0261.13631

Figure Lengend Snippet: SK2 channels contribute in store‐operated calcium entry (SOCE) and migration in high‐grade serous ovarian cancer (HGSOC) cells. (A) Effect of Lei‐Dab‐7 on current–density amplitude of COV504 cells. Lei‐Dab7 sensitive current–density–voltage relationships during voltage step cells before and after Lei‐Dab7 (10 n m ) perfusion ( N = 8). Sensitive current was obtained by subtracting the outward current recorded in the presence of Lei‐Dab7 from the net outward current observed in normal physiological saline solution (left panel). Current density measured at +30 mV (right panel). (B) SOCE measurements in COV504 (left panel) ( n = 12, N = 5) or OVCAR3 cells (right panel) ( n = 17, N = 5) using Fura‐2‐AM with or without acute Lei‐Dab7 administration. (C and D) Transwell migration assay with cells treated or not with Lei‐Dab7 (left panels) (COV504, N4; OVCAR3, N = 7) or siSK2 (right panels) (COV504, N = 8; OVCAR3, N = 4). (E) Plasma membrane and intracellular SK2 channel pools that contribute to cell migration and SOCE in HGSOC. The cell migration (C and D) and the Ca 2+ measurement amplitudes (B) were expressed as mean ± SEM, each point is the result of one experiment, and is normalized to the control condition (Mann–Whitney, P < 0.05*, P < 0.01**, P < 0.001***). The whole cell recording results (A) are represented as mean ± SEM (Wilcoxon, P < 0.01**) (Tg, Thapsigargin).

Article Snippet: Human high‐grade serous ovarian cancer cell lines COV504 and OVCAR3 were maintained, respectively, in DMEM and RPMI 1640 medium (Gibco, Illkirch, France) supplemented with 10% fetal bovine serum (FBS, Hyclone Lonza Bioscience, Illkirch, France) under 5% CO 2 at 37 °C.

Techniques: Migration, Saline, Transwell Migration Assay, Membrane, Control, MANN-WHITNEY

Journal: Molecular Oncology

Article Title: Plasma membrane SK2 channel activity regulates migration and chemosensitivity of high‐grade serous ovarian cancer cells

doi: 10.1002/1878-0261.13631

Figure Lengend Snippet: LPA increases the activity of plasma membrane SK2 and cell migration in a store‐operated calcium entry (SOCE) independent manner. (A) Effect of LPA pre‐treatment on SK2 current. Current density–voltage relationships obtained on COV504 cells before and after LPA treatment (10 μ m ) for 72 h and with or without acute Lei‐Dab7 application (10 n m ) (PSS Control, N = 6; LPA, N = 14; LPA + Lei‐Dab7, N = 6) (A). Current‐density measured at +30 mV (B) and evaluation of membrane potential (Em) on COV504 cells control and pre‐treated with LPA ± Lei‐Dab7 (C). (B) KCNN2 mRNA (left panel) and SK2 protein (right panel) expression level quantified by qRT‐PCR ( N = 4) and western blot ( N = 4), respectively. Measurements were performed on COV504 cells with or without LPA pre‐treatment (10 μ m ). (C) SOCE measurements in COV504 cells ( n = 16, N = 4) using Fura‐2‐AM fluorescent probe with or without acute Lei‐Dab7 application (10 n m ) on cells, in the presence or absence of LPA for 72 h (10 μ m ). (D) Transwell migration assay with COV504 (left panel) ( N = 5) or OVCAR3 (right panel) ( N = 7) cells with or without Lei‐Dab7 (10 n m ) or LPA pre‐treatment (72 h, 10 μ m ) for 24 h assay. (E) Hypothetical representation of LPA activity that induces SK2‐dependent cell migration but loss of SK2 channel participation in SOCE in HGSOC cells. Whole cell recording (A) is expressed as mean ± SEM (Wilcoxon, P < 0.05*, P < 0.01**, P < 0.001***). Results from qRT‐PCR (B, left panel), western blots (B, right panel), Ca 2+ measurements (C), and migration assay (D) are expressed as mean ± SEM, each point is the result of one experiment, and is normalized to the control condition (Mann–Whitney, P < 0.05*, P < 0.01** (B), One‐way ANOVA, P < 0.05*, P < 0.01** (C, D)) (LPA, lysophosphatidic acid; Tg, Thapsigargin).

Article Snippet: Human high‐grade serous ovarian cancer cell lines COV504 and OVCAR3 were maintained, respectively, in DMEM and RPMI 1640 medium (Gibco, Illkirch, France) supplemented with 10% fetal bovine serum (FBS, Hyclone Lonza Bioscience, Illkirch, France) under 5% CO 2 at 37 °C.

Techniques: Activity Assay, Membrane, Migration, Control, Expressing, Quantitative RT-PCR, Western Blot, Transwell Migration Assay, MANN-WHITNEY

Journal: Molecular Oncology

Article Title: Plasma membrane SK2 channel activity regulates migration and chemosensitivity of high‐grade serous ovarian cancer cells

doi: 10.1002/1878-0261.13631

Figure Lengend Snippet: Plasma membrane SK2 activity increases Taxol® sensitivity in sensitive and resistant cell lines. In the presence or absence of Lei‐Dab7 (10 n m ), cells were treated with a range of Taxol® concentration to evaluate EC 50 values in a 7‐day survival assay in OVCAR3 ( N = 8) (A), and COV504 ( N = 6) (B), OVCAR3 TX ( N = 5) (C), and COV504 TX ( N = 6) (D) cells. EC 50 is the dose for which we obtained 50% of the drug's maximal effect. EC 50 increase is associated with drug resistance. On the right, histograms represent EC 50 values in the presence of Lei‐Dab7. Each point is the result of one experiment. For the statistical analysis of EC 50 in OVCAR3 TX + Lei‐Dab7 condition, the maximal value of the Taxol® range was used (40 n m ) (representing by a dot line on C right panel). The survival assay results are expressed as mean ± SEM (Wilcoxon, P < 0.05*) (OVCAR3 TX and COV504 TX = Taxol® resistant cells).

Article Snippet: Human high‐grade serous ovarian cancer cell lines COV504 and OVCAR3 were maintained, respectively, in DMEM and RPMI 1640 medium (Gibco, Illkirch, France) supplemented with 10% fetal bovine serum (FBS, Hyclone Lonza Bioscience, Illkirch, France) under 5% CO 2 at 37 °C.

Techniques: Membrane, Activity Assay, Concentration Assay, Clonogenic Cell Survival Assay

Journal: Molecular Oncology

Article Title: Plasma membrane SK2 channel activity regulates migration and chemosensitivity of high‐grade serous ovarian cancer cells

doi: 10.1002/1878-0261.13631

Figure Lengend Snippet: SK2 channels contribute in store‐operated calcium entry (SOCE) and migration in high‐grade serous ovarian cancer (HGSOC) cells. (A) Effect of Lei‐Dab‐7 on current–density amplitude of COV504 cells. Lei‐Dab7 sensitive current–density–voltage relationships during voltage step cells before and after Lei‐Dab7 (10 n m ) perfusion ( N = 8). Sensitive current was obtained by subtracting the outward current recorded in the presence of Lei‐Dab7 from the net outward current observed in normal physiological saline solution (left panel). Current density measured at +30 mV (right panel). (B) SOCE measurements in COV504 (left panel) ( n = 12, N = 5) or OVCAR3 cells (right panel) ( n = 17, N = 5) using Fura‐2‐AM with or without acute Lei‐Dab7 administration. (C and D) Transwell migration assay with cells treated or not with Lei‐Dab7 (left panels) (COV504, N4; OVCAR3, N = 7) or siSK2 (right panels) (COV504, N = 8; OVCAR3, N = 4). (E) Plasma membrane and intracellular SK2 channel pools that contribute to cell migration and SOCE in HGSOC. The cell migration (C and D) and the Ca 2+ measurement amplitudes (B) were expressed as mean ± SEM, each point is the result of one experiment, and is normalized to the control condition (Mann–Whitney, P < 0.05*, P < 0.01**, P < 0.001***). The whole cell recording results (A) are represented as mean ± SEM (Wilcoxon, P < 0.01**) (Tg, Thapsigargin).

Article Snippet: Human high‐grade serous ovarian cancer cell lines COV504 and OVCAR3 were maintained, respectively, in DMEM and RPMI 1640 medium (Gibco, Illkirch, France) supplemented with 10% fetal bovine serum (FBS, Hyclone Lonza Bioscience, Illkirch, France) under 5% CO 2 at 37 °C.

Techniques: Migration, Saline, Transwell Migration Assay, Membrane, Control, MANN-WHITNEY

Journal: Molecular Oncology

Article Title: Plasma membrane SK2 channel activity regulates migration and chemosensitivity of high‐grade serous ovarian cancer cells

doi: 10.1002/1878-0261.13631

Figure Lengend Snippet: LPA increases the activity of plasma membrane SK2 and cell migration in a store‐operated calcium entry (SOCE) independent manner. (A) Effect of LPA pre‐treatment on SK2 current. Current density–voltage relationships obtained on COV504 cells before and after LPA treatment (10 μ m ) for 72 h and with or without acute Lei‐Dab7 application (10 n m ) (PSS Control, N = 6; LPA, N = 14; LPA + Lei‐Dab7, N = 6) (A). Current‐density measured at +30 mV (B) and evaluation of membrane potential (Em) on COV504 cells control and pre‐treated with LPA ± Lei‐Dab7 (C). (B) KCNN2 mRNA (left panel) and SK2 protein (right panel) expression level quantified by qRT‐PCR ( N = 4) and western blot ( N = 4), respectively. Measurements were performed on COV504 cells with or without LPA pre‐treatment (10 μ m ). (C) SOCE measurements in COV504 cells ( n = 16, N = 4) using Fura‐2‐AM fluorescent probe with or without acute Lei‐Dab7 application (10 n m ) on cells, in the presence or absence of LPA for 72 h (10 μ m ). (D) Transwell migration assay with COV504 (left panel) ( N = 5) or OVCAR3 (right panel) ( N = 7) cells with or without Lei‐Dab7 (10 n m ) or LPA pre‐treatment (72 h, 10 μ m ) for 24 h assay. (E) Hypothetical representation of LPA activity that induces SK2‐dependent cell migration but loss of SK2 channel participation in SOCE in HGSOC cells. Whole cell recording (A) is expressed as mean ± SEM (Wilcoxon, P < 0.05*, P < 0.01**, P < 0.001***). Results from qRT‐PCR (B, left panel), western blots (B, right panel), Ca 2+ measurements (C), and migration assay (D) are expressed as mean ± SEM, each point is the result of one experiment, and is normalized to the control condition (Mann–Whitney, P < 0.05*, P < 0.01** (B), One‐way ANOVA, P < 0.05*, P < 0.01** (C, D)) (LPA, lysophosphatidic acid; Tg, Thapsigargin).

Article Snippet: Human high‐grade serous ovarian cancer cell lines COV504 and OVCAR3 were maintained, respectively, in DMEM and RPMI 1640 medium (Gibco, Illkirch, France) supplemented with 10% fetal bovine serum (FBS, Hyclone Lonza Bioscience, Illkirch, France) under 5% CO 2 at 37 °C.

Techniques: Activity Assay, Membrane, Migration, Control, Expressing, Quantitative RT-PCR, Western Blot, Transwell Migration Assay, MANN-WHITNEY

Journal: Molecular Oncology

Article Title: Plasma membrane SK2 channel activity regulates migration and chemosensitivity of high‐grade serous ovarian cancer cells

doi: 10.1002/1878-0261.13631

Figure Lengend Snippet: Plasma membrane SK2 activity increases Taxol® sensitivity in sensitive and resistant cell lines. In the presence or absence of Lei‐Dab7 (10 n m ), cells were treated with a range of Taxol® concentration to evaluate EC 50 values in a 7‐day survival assay in OVCAR3 ( N = 8) (A), and COV504 ( N = 6) (B), OVCAR3 TX ( N = 5) (C), and COV504 TX ( N = 6) (D) cells. EC 50 is the dose for which we obtained 50% of the drug's maximal effect. EC 50 increase is associated with drug resistance. On the right, histograms represent EC 50 values in the presence of Lei‐Dab7. Each point is the result of one experiment. For the statistical analysis of EC 50 in OVCAR3 TX + Lei‐Dab7 condition, the maximal value of the Taxol® range was used (40 n m ) (representing by a dot line on C right panel). The survival assay results are expressed as mean ± SEM (Wilcoxon, P < 0.05*) (OVCAR3 TX and COV504 TX = Taxol® resistant cells).

Article Snippet: Human high‐grade serous ovarian cancer cell lines COV504 and OVCAR3 were maintained, respectively, in DMEM and RPMI 1640 medium (Gibco, Illkirch, France) supplemented with 10% fetal bovine serum (FBS, Hyclone Lonza Bioscience, Illkirch, France) under 5% CO 2 at 37 °C.

Techniques: Membrane, Activity Assay, Concentration Assay, Clonogenic Cell Survival Assay