Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Prosaposin orchestrates a TGFβ1-driven paracrine loop between Schwann cells and gastric cancer to accelerate perineural invasion

doi: 10.1186/s13046-026-03652-3

Figure Lengend Snippet: SCs-Induced PSAP Overexpression Potentiates GC Malignancy. A Venn analysis of differentially expressed proteins (DEPs) in the co-culture system. B IHC validation of PSAP upregulation in PNI-positive GC tissues. C Western Blot (WB) confirm PSAP Induction in co-cultured GC cells. D PSAP augments migration, invasion, and clonogenic capacity of GC cells. E – F The possible interacting proteins of PSAP were analyzed by co-immunoprecipitation and mass spectrometry. G Pull-down assay was used to verify the interaction of PSAP-CTSD-GALC. H Scanning electron microscopy was used to detect autophagosomes. I Inhibition of Autophagy Mediated by the PSAP–CTSD–GALC Complex. J mRFP-GFP-LC3B adenovirus reporter was used to detect autophagic flux. K Autophagic flux inhibition attenuates tumor-promoting effects of PSAP overexpression

Article Snippet: Furthermore, both the expression and secretion of TGFβ1 were found to be significantly increased in SCs exposed to GC cells and recombinant PSAP (rPSAP) (MCE, USA, #HY- P76553 , 50 ng/ml, 24 h) (Figs. C and D).

Techniques: Over Expression, Co-Culture Assay, Biomarker Discovery, Western Blot, Cell Culture, Migration, Immunoprecipitation, Mass Spectrometry, Pull Down Assay, Electron Microscopy, Inhibition

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Prosaposin orchestrates a TGFβ1-driven paracrine loop between Schwann cells and gastric cancer to accelerate perineural invasion

doi: 10.1186/s13046-026-03652-3

Figure Lengend Snippet: Bidirectional PSAP-TGFβ1 Paracrine Signaling Sustains SCs–GC Crosstalk. A Schematic of paracrine communication between SCs and GC Cells. B The secretion of PSAP by GC cells increased after co-culture with SCs. C TGFβ1 expression was increased in SCs co-cultured with GC cells and treated with rPSAP. D TGFβ1 secretion was increased in SCs co-cultured with GC cells and treated with rPSAP. E – F The secretion and expression of PSAP in GC cells treated with rTGFβ1 were increased. G - H The TGFβ1 inhibitor (Asiaticoside) can inhibit the effect of rTGFβ1 on the secretion and expression of PSAP

Article Snippet: Furthermore, both the expression and secretion of TGFβ1 were found to be significantly increased in SCs exposed to GC cells and recombinant PSAP (rPSAP) (MCE, USA, #HY- P76553 , 50 ng/ml, 24 h) (Figs. C and D).

Techniques: Co-Culture Assay, Expressing, Cell Culture

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Prosaposin orchestrates a TGFβ1-driven paracrine loop between Schwann cells and gastric cancer to accelerate perineural invasion

doi: 10.1186/s13046-026-03652-3

Figure Lengend Snippet: PSAP Activates GPR37/RAC1/ACTB Signaling to Drive TGFβ1 Secretion in SCs. A Schematic representation of PSAP secreted by GC cells acting on SCs. B-D rPSAP enhances SCs proliferation, migration, invasion and clonogenic capacity. E Functional enrichment analysis showed that the cytoskeleton of SCs changed after co-culture significantly. F Phalloidin staining reveals cytoskeletal changes in SCs following co-culture and rPSAP treatment. G SPR demonstrated direct binding between PASP and GPR37. H SCs co-cultured and exposed to rPSAP significantly activated GPR37/RAC1/ACTB signaling axis and TGFβ1 expression. I-K GPR37 sustains RAC1–ACTB signaling to drive TGF-β1 production and SC aggressiveness, conferring responsiveness to rPSAP

Article Snippet: Furthermore, both the expression and secretion of TGFβ1 were found to be significantly increased in SCs exposed to GC cells and recombinant PSAP (rPSAP) (MCE, USA, #HY- P76553 , 50 ng/ml, 24 h) (Figs. C and D).

Techniques: Migration, Functional Assay, Co-Culture Assay, Staining, Binding Assay, Cell Culture, Expressing

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Prosaposin orchestrates a TGFβ1-driven paracrine loop between Schwann cells and gastric cancer to accelerate perineural invasion

doi: 10.1186/s13046-026-03652-3

Figure Lengend Snippet: TGFβ1 Engages the TGFβ1/Smad4/Sortilin Axis to Amplify PSAP Secretion and PNI. A Schematic representation of TGFβ1 secreted by SCs acting on GC cells. B In vitro PNI assays showed that downregulation of SCs-derived TGF-β1 diminished GC cell PNI. C-E Asiaticoside can inhibit the effects of rTGFβ1 on the proliferation, invasion and PSAP secretion of GC cells. F Schematic representation of PSAP secretion. G TGFβ1/Smad4 signaling activation induces increased PSAP secretion through the suppression of Sortilin expression. H Dual-luciferase and ChIP-qPCR analyses showed that Smad4 binds the Sortilin promoter and represses its transcription, linking TGF-β1/Smad4 activation to Sortilin downregulation. I Sortilin overexpression suppresses PSAP secretion

Article Snippet: Furthermore, both the expression and secretion of TGFβ1 were found to be significantly increased in SCs exposed to GC cells and recombinant PSAP (rPSAP) (MCE, USA, #HY- P76553 , 50 ng/ml, 24 h) (Figs. C and D).

Techniques: In Vitro, Derivative Assay, Activation Assay, Expressing, Luciferase, ChIP-qPCR, Over Expression

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Prosaposin orchestrates a TGFβ1-driven paracrine loop between Schwann cells and gastric cancer to accelerate perineural invasion

doi: 10.1186/s13046-026-03652-3

Figure Lengend Snippet: Therapeutic Targeting of PSAP/TGFβ1 Suppresses PNI In Vivo. A Inhibition of PSAP/TGFβ1 reduces PNI Incidence DRG-PNI model in vitro . B Schematic of a Sciatic Nerve Invasion Murine Model. C-D Tumor formation and H&E and IHC detection in the sciatic nerve model. E – F Functional and physiological assessments post intervention (Sciatic Nerve Score, Body Weight). G GMulticolor IF was used to verify the spatial distribution of PSAP, TGFβ1 and SCs(S100β) in PNI-positive tumor tissues

Article Snippet: Furthermore, both the expression and secretion of TGFβ1 were found to be significantly increased in SCs exposed to GC cells and recombinant PSAP (rPSAP) (MCE, USA, #HY- P76553 , 50 ng/ml, 24 h) (Figs. C and D).

Techniques: In Vivo, Inhibition, In Vitro, Functional Assay

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Prosaposin orchestrates a TGFβ1-driven paracrine loop between Schwann cells and gastric cancer to accelerate perineural invasion

doi: 10.1186/s13046-026-03652-3

Figure Lengend Snippet: PSAP/TGFβ1/S100β multimodal signatures correlate with PNI and improve PNI discrimination. A IHC Staining of PSAP, TGFβ1, and S100β in PNI Subgroups. B Kaplan–Meier Survival Analysis by PNI Status in a Clinical Cohort. C Nomogram of PSAP, TGFβ1 and S100β combined to predict PNI. D - F ROC curve analysis, DCA, and calibration curves for comparison of PTS model and Baseline model for predicting PNI status. G The PTS model performance SHAP analysis. H - I ROC and calibration curves for the PTS and baseline models in an independent validation cohort. J Reclassification analysis of the PTS model and Baseline model

Article Snippet: Furthermore, both the expression and secretion of TGFβ1 were found to be significantly increased in SCs exposed to GC cells and recombinant PSAP (rPSAP) (MCE, USA, #HY- P76553 , 50 ng/ml, 24 h) (Figs. C and D).

Techniques: Immunohistochemistry, Comparison, Biomarker Discovery

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Prosaposin orchestrates a TGFβ1-driven paracrine loop between Schwann cells and gastric cancer to accelerate perineural invasion

doi: 10.1186/s13046-026-03652-3

Figure Lengend Snippet: Bidirectional PSAP-TGFβ1 Paracrine Signaling Sustains SCs–GC Crosstalk. A Schematic of paracrine communication between SCs and GC Cells. B The secretion of PSAP by GC cells increased after co-culture with SCs. C TGFβ1 expression was increased in SCs co-cultured with GC cells and treated with rPSAP. D TGFβ1 secretion was increased in SCs co-cultured with GC cells and treated with rPSAP. E – F The secretion and expression of PSAP in GC cells treated with rTGFβ1 were increased. G - H The TGFβ1 inhibitor (Asiaticoside) can inhibit the effect of rTGFβ1 on the secretion and expression of PSAP

Article Snippet: Secreted PSAP and TGFβ1 levels in cell supernatants were quantified using Human PSAP (CUSABIO, China, #CSB-E12837h) and Rat TGFβ1 (JIANGLAI BIO, China, # JL12342,) ELISA kits.

Techniques: Co-Culture Assay, Expressing, Cell Culture

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Prosaposin orchestrates a TGFβ1-driven paracrine loop between Schwann cells and gastric cancer to accelerate perineural invasion

doi: 10.1186/s13046-026-03652-3

Figure Lengend Snippet: PSAP Activates GPR37/RAC1/ACTB Signaling to Drive TGFβ1 Secretion in SCs. A Schematic representation of PSAP secreted by GC cells acting on SCs. B-D rPSAP enhances SCs proliferation, migration, invasion and clonogenic capacity. E Functional enrichment analysis showed that the cytoskeleton of SCs changed after co-culture significantly. F Phalloidin staining reveals cytoskeletal changes in SCs following co-culture and rPSAP treatment. G SPR demonstrated direct binding between PASP and GPR37. H SCs co-cultured and exposed to rPSAP significantly activated GPR37/RAC1/ACTB signaling axis and TGFβ1 expression. I-K GPR37 sustains RAC1–ACTB signaling to drive TGF-β1 production and SC aggressiveness, conferring responsiveness to rPSAP

Article Snippet: Secreted PSAP and TGFβ1 levels in cell supernatants were quantified using Human PSAP (CUSABIO, China, #CSB-E12837h) and Rat TGFβ1 (JIANGLAI BIO, China, # JL12342,) ELISA kits.

Techniques: Migration, Functional Assay, Co-Culture Assay, Staining, Binding Assay, Cell Culture, Expressing

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Prosaposin orchestrates a TGFβ1-driven paracrine loop between Schwann cells and gastric cancer to accelerate perineural invasion

doi: 10.1186/s13046-026-03652-3

Figure Lengend Snippet: TGFβ1 Engages the TGFβ1/Smad4/Sortilin Axis to Amplify PSAP Secretion and PNI. A Schematic representation of TGFβ1 secreted by SCs acting on GC cells. B In vitro PNI assays showed that downregulation of SCs-derived TGF-β1 diminished GC cell PNI. C-E Asiaticoside can inhibit the effects of rTGFβ1 on the proliferation, invasion and PSAP secretion of GC cells. F Schematic representation of PSAP secretion. G TGFβ1/Smad4 signaling activation induces increased PSAP secretion through the suppression of Sortilin expression. H Dual-luciferase and ChIP-qPCR analyses showed that Smad4 binds the Sortilin promoter and represses its transcription, linking TGF-β1/Smad4 activation to Sortilin downregulation. I Sortilin overexpression suppresses PSAP secretion

Article Snippet: Secreted PSAP and TGFβ1 levels in cell supernatants were quantified using Human PSAP (CUSABIO, China, #CSB-E12837h) and Rat TGFβ1 (JIANGLAI BIO, China, # JL12342,) ELISA kits.

Techniques: In Vitro, Derivative Assay, Activation Assay, Expressing, Luciferase, ChIP-qPCR, Over Expression

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Prosaposin orchestrates a TGFβ1-driven paracrine loop between Schwann cells and gastric cancer to accelerate perineural invasion

doi: 10.1186/s13046-026-03652-3

Figure Lengend Snippet: Therapeutic Targeting of PSAP/TGFβ1 Suppresses PNI In Vivo. A Inhibition of PSAP/TGFβ1 reduces PNI Incidence DRG-PNI model in vitro . B Schematic of a Sciatic Nerve Invasion Murine Model. C-D Tumor formation and H&E and IHC detection in the sciatic nerve model. E – F Functional and physiological assessments post intervention (Sciatic Nerve Score, Body Weight). G GMulticolor IF was used to verify the spatial distribution of PSAP, TGFβ1 and SCs(S100β) in PNI-positive tumor tissues

Article Snippet: Secreted PSAP and TGFβ1 levels in cell supernatants were quantified using Human PSAP (CUSABIO, China, #CSB-E12837h) and Rat TGFβ1 (JIANGLAI BIO, China, # JL12342,) ELISA kits.

Techniques: In Vivo, Inhibition, In Vitro, Functional Assay

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Prosaposin orchestrates a TGFβ1-driven paracrine loop between Schwann cells and gastric cancer to accelerate perineural invasion

doi: 10.1186/s13046-026-03652-3

Figure Lengend Snippet: PSAP/TGFβ1/S100β multimodal signatures correlate with PNI and improve PNI discrimination. A IHC Staining of PSAP, TGFβ1, and S100β in PNI Subgroups. B Kaplan–Meier Survival Analysis by PNI Status in a Clinical Cohort. C Nomogram of PSAP, TGFβ1 and S100β combined to predict PNI. D - F ROC curve analysis, DCA, and calibration curves for comparison of PTS model and Baseline model for predicting PNI status. G The PTS model performance SHAP analysis. H - I ROC and calibration curves for the PTS and baseline models in an independent validation cohort. J Reclassification analysis of the PTS model and Baseline model

Article Snippet: Secreted PSAP and TGFβ1 levels in cell supernatants were quantified using Human PSAP (CUSABIO, China, #CSB-E12837h) and Rat TGFβ1 (JIANGLAI BIO, China, # JL12342,) ELISA kits.

Techniques: Immunohistochemistry, Comparison, Biomarker Discovery

Journal: bioRxiv

Article Title: Prosaposin is cleaved into saposins by multiple cathepsins in a progranulin-regulated fashion

doi: 10.1101/2024.02.15.580326

Figure Lengend Snippet: Human recombinant prosaposin (PSAP, 400nM) was incubated at 37°C for 1 hour with various human recombinant cathepsins (400nM) under four pH conditions (3.5, 4,5, 5.5, and 7.4) and cleavage was determined via silver stain. A , Aspartyl proteases CTSD and CTSE, B , cysteine proteases CTSB, CTSC, CTSF, CTSH, CTSK, AEP/LGMN, CTSL, CTSO, CTSS, CTSV, CTSW, and CTSX, and C , serine proteases CTSA and CTSG were tested. * indicates the cathepsin band for respective experiments.

Article Snippet: As a positive control, I tested the antibodies against re-combinant human prosaposin (Abcam #167924) alone and observed the expected band sizes.

Techniques: Recombinant, Incubation, Silver Staining

Journal: bioRxiv

Article Title: Prosaposin is cleaved into saposins by multiple cathepsins in a progranulin-regulated fashion

doi: 10.1101/2024.02.15.580326

Figure Lengend Snippet: A , Model of PSAP cleavage into saposins. Human recombinant prosaposin (PSAP, 400nM) was incubated at 37°C for either a 30 minute or 6 hour time course with various human recombinant cathepsins (400nM) at their optimal pH. B-C , Aspartyl proteases CTSD and CTSE, D-I , cysteine proteases CTSB, AEP/LGMN, CTSK, CTSL, CTSS, and CTSV, and J , serine protease CTSG were tested. Samples were run on western blot and probed with α-SapA, α-SapB, α-SapC, α-SapD antibodies. All enzymes were tested at pH of 4.5, with the exception of CTSG, which was tested at its optimal pH of 7.4.

Article Snippet: As a positive control, I tested the antibodies against re-combinant human prosaposin (Abcam #167924) alone and observed the expected band sizes.

Techniques: Recombinant, Incubation, Western Blot

Journal: bioRxiv

Article Title: Prosaposin is cleaved into saposins by multiple cathepsins in a progranulin-regulated fashion

doi: 10.1101/2024.02.15.580326

Figure Lengend Snippet: A , Model of progranulin (PGRN) showing full length, and the three multi-granulin fragments (MGFs) pG, BAC, and CDE. * indicates the PSAP binding site on PGRN. B-E , Human recombinant prosaposin (PSAP,) was incubated at 37°C for a 6 hour time course with CTSD (400nM) and full-length PGRN, pG, BAC, or CDE (400nM) at pH 4.5. Samples were run on western blot and probed with α-SapA, α-SapB, α-SapC, α-SapD antibodies.

Article Snippet: As a positive control, I tested the antibodies against re-combinant human prosaposin (Abcam #167924) alone and observed the expected band sizes.

Techniques: Binding Assay, Recombinant, Incubation, Western Blot