Journal: iScience
Article Title: miR-181d coordinates homologous recombination and anti-tumor immune responses in glioblastoma
doi: 10.1016/j.isci.2026.115077
Figure Lengend Snippet: miR-181d sensitized temozolomide-induced radiation resistance (A) Temozolomide (TMZ) treatment-induced homologous recombination (HR) was abolished by RAD51 silencing or miR-181d transfection. Left: schematic of the extrachromosomal HR assay. The assay is based on co-transformation of two plasmids (dl-1 and dl-2) into the CMK3 cells, followed by the isolation of genomic DNA. HR events between these plasmids resulted in a recombinant DNA of 420 bp. Right : CMK3 parental and three independent TMZ-resistant clones (labeled 1, 2, and 3) were transfected with si NT , si RAD51 , miR-181d, or their combination. Twenty-four hours post-transfection, the cells were transfected with dl-1 and dl-2 plasmids. Genomic DNA was isolated after 48 h, and qPCR analysis of the recombinant 420-bp DNA was performed. ∗∗∗ p < 0.001(Student’s t test). Data are presented as the mean ± SD ( n = 3 independent experiments). (B) In vitro TMZ-induced radiation resistance is abolished by miR-181d transfection. CMK3 parental and TMZ-resistant cells were transfected with miR-NT or miR-181d for 24 h, followed by treatment with 0 or 6 Gy ionizing radiation (IR). Clonogenic survival was determined subsequently. ∗∗∗ p < 0.001, ∗∗ p < 0.01, ∗ p < 0.05 (Student’s t test). Data are presented as the mean ± SD ( n = 5 independent experiments). (C) miR-181d enhanced γ-H2AX foci accumulation in TMZ-resistant cells in response to IR. Representative immunofluorescence images of γ-H2AX foci in CMK3 parental and resistant cells transfected with miR-NT or miR-181d exposed to 0 or 6 Gy of IR (upper). Quantification of γ-H2AX foci is provided (lower). ∗∗∗ p < 0.001 between indicated groups (Student’s t test). Scale bars are 5 μm. (D) In vivo TMZ-induced radiation resistance is abolished by miR-181d transfection. Kaplan-Meier survival curves of nude mice bearing orthotopic implant of patient-derived glioblastoma xenograft CMK3 (P) or a TMZ-resistant (R) clone isolated after TMZ treatment. The cells were transfected with miR-NT or miR-181d before implant. The mice underwent 5 days of 2 Gy/day IR starting 7 days after tumor implant ( n = 8 mice/group).
Article Snippet: Anti-RAD51 antibody , Cell Signaling Technology , RRID: AB_2721109.
Techniques: Homologous Recombination, Transfection, Transformation Assay, Isolation, Recombinant, Clone Assay, Labeling, In Vitro, Immunofluorescence, In Vivo, Derivative Assay