Fig 2: hAMSC-GDNF exhibited a better neural-like cell differentiation capacity in vivo. (A) Schematic diagram showing quantification of the differentiation capacity of hAMSCs in the mice brains. (B, E, and H) Representative images showing the number of Nestin-, GDNF-, and Tuj-1-positive cells immunostaining assays. (C and D) When hAMSCs were engineered with GDNF, the expression of Nestin-positive cells was significantly higher than that seen in the hAMSC-vector group in vivo. (F and G) The number of GFAP-positive cells with hAMSC-GDNF was higher than the hAMSC-vector group in vivo. (I and J) When the hAMSCs were loaded with GDNF, the expression of Tuj-1 exhibited a statistically significant increase than hAMSC-vector group. Scale bar, 50 µm. Error bars represent SEM. *P < 0.05, **P < 0.01, ***P < 0.001. GDNF: glial cell line-derived neurotrophic factor; GFAP: glial fibrillary acidic protein; GFP: green fluorescent protein; hAMSCs: human primary adipose-derived mesenchymal stem cells; SEM: standard error of the mean.

Fig 3: hAMSC-GDNF promotes therapeutic effects in PD models. (A) Representative immunofluorescence staining pictures of TH in the different groups, scale bar, 200 µm. (B–E) Immunostaining assays showed that the volume of grafts, the number, and density of TH-positive cells in the PD/hAMSC-GDNF group were significantly higher than the other groups. (F–I) The number of TH- and NeuN-positive cells in the PD/hAMSC-GDNF group was larger than in the PD/hAMSC-vector group in 6-OHDA lesioned mouse models. Scale bar, 50 µm. Error bars represent SEM. *P < 0.05, **P < 0.01, ***P < 0.001. GDNF: glial cell line-derived neurotrophic factor; GFP: green fluorescent protein; hAMSCs: human primary adipose-derived mesenchymal stem cells; OD: optical density; PD: Parkinson’s disease; SEM: standard error of the mean; TH: tyrosine hydroxylase.

Fig 4: Expression of RET ligands contributes to endocrine resistance.(a) Density scatterplot showing RET and ESR1 expression in mRNA-seq data from 1,177 primary breast cancer models in the cancer genome atlas (TCGA). Spearman’s ? = 0.51, p = 1.2e-60. (b) Transcription near the RET locus in B7TamS and G11TamR cells. PRO-seq densities on sense strand and anti-sense strand are shown in red and blue, respectively. dREG scores are shown in green. Enhancers and promoters are shown in grey and light green shading, respectively. Arrow indicates the directional movement of transcribed genes. (c) Dot plot shows RET transcription levels in TamS and TamR MCF-7 cells. (d) Density scatterplots show the expression of RET ligands (GDNF, NRTN, ARTN, and PSPN) versus ESR1 based on mRNA-seq data from 1,177 primary breast cancers. (e) RET ligand expression distribution in ER+ breast cancers. The dotted blue line represents 2.5 times the range between the 25th and 50th percentile. (f) Fraction of ER+ breast cancers (n = 925) with at least one RET ligand exceeding the threshold shown in panel E (shown in dark blue, n = 122). Among the 4 RET ligands, GDNF was the most highly expressed (n = 60). (g) Boxplots show RET ligands score and RET expression levels in patients that respond or do not respond to aromatase inhibitor letrozole. * p = 0.016.

Fig 5: GDNF secretion enhanced the neural-like cell differentiation capacity of hAMSC in mouse models of PD. (A, D, G, and J) Representative immunofluorescence staining pictures of GDNF, Nestin, GFAP, and Tuj-1 expression and neural-like cell differentiation in PD/hAMSC-vector and PD/hAMSC-GDNF groups, scale bar, 50 µm. (B and C) Immunofluorescence staining assay indicated that the hAMSCs could secrete GDNF steadily in the PD/hAMSC-GDNF group but not in the PD/hAMSC-vector group. (E & F, H & I, and K & L) The PD/hAMSC-GDNF group showed a higher number of GDNF-, Nestin-, GFAP-, and Tuj-1-positive cells compared to the PD/hAMSC-vector group. Error bars represent SEM. *P < 0.05, **P < 0.01, ***P < 0.001. GDNF: glial cell line-derived neurotrophic factor; GFAP: glial fibrillary acidic protein; hAMSCs: human primary adipose-derived mesenchymal stem cells; SEM: standard error of the mean.