Figures & data
Figure 1 FOXD2-AS1 was highly expressed in cisplatin-resistant non-small-cell lung cancer (NSCLC) and cells.
Notes: (A) Expression of FOXD2-AS1 in cisplatin-sensitive or -resistant NSCLC tissue was detected by reverse-transcription (RT)-qPCR. (B, C) CCK8 assay assessed viability and IC50 of DDP-sensitive or -resistant NSCLC. (D) Expression of FOXD2-AS1 in DDP-sensitive or -resistant NSCLC cells was measured by RT-qPCR. *P<0.05.
Figure 2 Lack of FOXD2-AS1 enhanced drug sensitivity of DDP-resistant NSCLC cells. A549/DDP and H1299/DDP cells were transfected with si-NC or si-FOXD2-AS1.
Figure 3 FOXD2-AS1 bound to miR185-5p and negatively regulated its expression.
Notes: (A) Putative binding regions of FOXD2-AS1 in miR185-5p predicted with biological software. (B, C) Luciferase activity of wild-type or mutant FOXD2-AS1 in A549/DDP cells following miRNC, miR185-5p, anti-miRNC, or anti-miR185-5p transfection determined by luciferase reporter assay. (D) Correlations between FOXD2-AS1 and miR185-5p detected by RIP assay. (E, F) Expression of miR185-5p in DDP-resistant non-small-cell lung cancer (NSCLC) tissue and cell lines detected by RT-qPCR assay. (G, H) Expression of FOXD2-AS1 and miR185-5p in A549/DDP and H1299/DDP cells, initially transfected with pcDNA, pcDNA-FOXD2-AS1, si-NC, or si-FOXD2-AS1, determined by reverse-transcription (RT) qPCR assay. *P<0.05.
Figure 4 FOXD2-AS1 reversed miR185-5p-enhanced drug sensitivity in DDP-toleratant non-small-cell lung cancer (NSCLC) cells.
Notes: (A) miR185-5p expression in A549/DDP and H1299/DDP cells after transfection of miRNC or miR185-5p mimics. A549/DDP and H1299/DDP cells were transfected with miRNC, miR185-5p, miR185-5p + pcDNA, or miR185-5p + pcDNA-FOXD2-AS1, followed by evaluation of colony numbers (B), cell proliferation (C, D), migration (E), invasion (F), drug resistance–related LRP, Pgp, and MRP1 expression (G, H). *P<0.05.
Figure 5 SIX1 was a target of miR185-5p.
Notes: (A) Putative binding regions of miR185-5p in SIX1 3ʹUTR. (B, C) Luciferase activity of wild-type or mutant SIX1 in A549/DDP cells after transfection of miRNC, miR185-5p, anti-miRNC, or anti-miR185-5p. (D–F) mRNA and protein levels of SIX1 in DDP-resistant non-small-cell lung cancer (NSCLC) tissue and cell lines detected by reverse-transcription (RT) qPCR and Western blot assays. (G) Protein levels of SIX1 in miR185-5p or anti-miR185-5p–transfected A549/DDP and H1299/DDP cells. *P<0.05.
Figure 6 FOXD2-AS1 reduced the chemosensitivity of DDP-resistant non-small-cell lung cancer (NSCLC) cells via the miR185-5p–SIX1 axis.
Notes: (A) miR185-5p expression in anti-miRNC or anti-miR185-5p–transfected A549/DDP and H1299/DDP cells. (B and C) SIX1 expression at mRNA and protein levels in si-NC or si-SIX1–transfected A549/DDP and H1299/DDP cells. (C) A549/DDP and H1299/DDP cells were transfected with si-NC, si-SIX1, si-SIX1 + anti-miRNC, or si-SIX1 + anti-miR185-5p, followed by evaluation of colony numbers (D), cell proliferation (E and F), migration (G), invasion (H), and drug resistance–related proteins LRP, Pgp, and MRP1 expression (I and J). (K) SIX1 expression in A549/DDP and H1299/DDP following transfection of si-NC, si-FOXD2-AS1, si-FOXD2-AS1 + anti-miRNC, or si-FOXD2-AS1 + anti-miR185-5p. *P<0.05.
Figure 7 Knockdown of FOXD2-AS1 reduced DDP resistance of non-small-cell lung cancer (NSCLC) in vivo.
Notes: (A) Tumor volume detected every week after injection. (B) Tumor weight investigated at the end point of 35 days. Expression of FOXD2-AS1 (C), miR185-5p (D), and SIX1 protein (E, F) in tumor tissue examined. *P<0.05.
Figure S1 DDP-resistant NSCLC cells showed a lower growth inhibition rate compared with DDP-sensitive group. (A) The growth inhibition rate of A549 or A549/DDP was measured by CCK8 assay. (B) The growth inhibition rate of H1299 or H1299/DDP was measured by CCK8 assay. *p<0.05
Figure S2 Overexpression of SIX1 attenuated drug sensitivity of DDP-resistant NSCLC cells. A549/DDP and H1299/DDP cells were transfected with pcDNA-NC or pcDNA-SIX1. (A) SIX1 expression was determined by RT-qPCR. (B and C) CCK-8 assay was performed to detect cell proliferation. (D and E) Transwell analysis was carried out for the detection of cell migration and invasion. *p<0.05
