Journal: Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie

Article Title: Synergistic activity of S63845 and parthenolide to overcome acquired resistance to MEK1/2 inhibitor in melanoma cells: Mechanisms and therapeutic potential.

doi: 10.1016/j.biopha.2025.118183

Figure Lengend Snippet: Fig. 5. Parthenolide (PN) combined with S63845 disturbs the balance between pro-apoptotic NOXA and pro-survival MCL-1. A The transcript levels of NOXA were assessed by qRT-PCR in cells exposed to PN and S63845 used alone or in combination at indicated concentrations for 22 h. The NOXA mRNA levels were normalized to the expression of RPS17 and shown relative to untreated cells. Data are mean ± S.D.; n = 2–3, *P < 0.05 (two-tailed unpaired Student’s t-test). B Cells were exposed to PN and S63845 used alone or in combination at indicated concentrations for 24 h. NOXA and MCL-1 proteins were immunodetected in cell lysates by Western blotting, and their levels were normalized to the intensity of GAPDH bands. The optical density quantification is shown below the blots relative to control. Representative Western blots are demonstrated; n = 2.

Article Snippet: Primary antibodies against PARP (#9542), NOXA (#14766), p21 (#2947), MCL-1 (#94296), phospho-histone H2A.X (Ser139; #2577), MITF (#12590), phospho-NF-κB p65 (Ser536; #3033), NF-κB p65 (#6956), and β-actin (#4970) (Cell Signaling, Danvers, MA, USA) were used overnight (4 ◦C) at dilution 1:1000, while primary antibodies against GAPDH (sc-47724) (Santa Cruz Biotechnology, Santa Cruz, CA, USA) were used for 2 h at room temperature at dilution 1:1000.

Techniques: Quantitative RT-PCR, Expressing, Two Tailed Test, Western Blot, Control

Journal: Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie

Article Title: Synergistic activity of S63845 and parthenolide to overcome acquired resistance to MEK1/2 inhibitor in melanoma cells: Mechanisms and therapeutic potential.

doi: 10.1016/j.biopha.2025.118183

Figure Lengend Snippet: Fig. 6. Diagram illustrating possible mechanisms behind massive apoptosis synergistically induced in trametinib-resistant melanoma cells by S63845 and parthenolide. Similar cellular and molecular effects are dictated by this drug combination in trametinib (MEK1/2 inhibitor)-resistant melanoma cells regardless of their phenotypes (differentiated type: MITFhigh/NGFRlow or dedifferentiated type: MITFlow/NGFRhigh), and in resistant melanoma cells undergoing phenotypic reprograming associated with trametinib withdrawal (drug holiday). The interrelated importance of the levels of pro-survival MCL-1 and pro-apoptotic NOXA in generating apoptotic response is displayed as the circles. Changes in the size of circles refer to alterations upon indicated drug treatment in cell population average amounts of MCL-1 and NOXA proteins. Blunt arrows (┬) represent S63845-driven inhibition of MCL-1 activity. The high synergy scores quantifying the apoptotic response measured as increased externalization of phosphatidylserine were obtained for all investigated cell lines, and the results for trametinib-resistant cells exerting dedifferentiation phenotype are displayed as an example. Other indications of apoptotic cell death such as activation of caspase-3/7, phosphorylation of H2AX, and PARP cleavage are shown in Fig. 4.

Article Snippet: Primary antibodies against PARP (#9542), NOXA (#14766), p21 (#2947), MCL-1 (#94296), phospho-histone H2A.X (Ser139; #2577), MITF (#12590), phospho-NF-κB p65 (Ser536; #3033), NF-κB p65 (#6956), and β-actin (#4970) (Cell Signaling, Danvers, MA, USA) were used overnight (4 ◦C) at dilution 1:1000, while primary antibodies against GAPDH (sc-47724) (Santa Cruz Biotechnology, Santa Cruz, CA, USA) were used for 2 h at room temperature at dilution 1:1000.

Techniques: Inhibition, Activity Assay, Activation Assay, Phospho-proteomics