LncRNA HOXA-AS2 Promotes Temozolomide Resistance in Glioblastoma by Regulated miR-302a-3p/IGF1 Axis

Figure 4

miR-302a-3p targets IGF1 and thereby reduces GBM cell resistance to TMZ. (a) IGF1 was identified as a putative miR-302a-3p target gene. (b) HEK293T cells were used to perform luciferase assays in which cells had been cotransfected with miR-302a-3p and WT or mutated (MUT) IGF1 3’-UTR reporter constructs. (c, d) IGF1 levels were detected in GBMTR cells via qPCR (c) and ELISA (d). (e, f) IGF1 levels in GBMTR cells were analyzed via qPCR (e) or ELISA (f) following transfection with miR-302a-3p inhibitor, mimic, or NC control constructs. (g) Levels of IGF1 were assessed in TMZ-resistant (n = 132) and sensitive (n = 132) GBM patient tissues. (h) IGF1 levels were negatively correlated with miR-302a-3p levels in tissue samples from GBM patients resistant to TMZ. (i, j) Both qPCR (i) and ELISA (j) approaches were employed to measure IGF1 levels in GBMTR cells following IGF1-specific or control siRNA transfection. (k) GBMTR cell viability was measured via CCK-8 assay after treatment with the indicated TMZ doses, and IC50 values were calculated. .

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