Impact of the PD-1/PD-L1 inhibitor SCL-1 on MDA-MB231 tumor growth in a humanized MHC-double knockout NOG mouse model

Abstract Although triple-negative breast cancers are still challenging to treat, the development of novel neoadjuvant chemotherapy combined with immune checkpoint antibodies is promising. Our group developed the small compound-based anti-PD-1/PD-L1 inhibitor SCL-1 and reported its potent anti-tumor...

Full description

Saved in:
Bibliographic Details
Main Authors: Tomoatsu Ikeya, Tadashi Ashizawa, Akari Kanematsu, Chie Maeda, Akira Iizuka, Kazue Yamashita, Haruo Miyata, Yasufumi Kikuchi, Kouji Maruyama, Mamoru Ito, Ken Yamaguchi, Yasuto Akiyama
Format: Article
Language:English
Published: Nature Portfolio 2025-07-01
Series:Scientific Reports
Subjects:
Online Access:https://doi.org/10.1038/s41598-025-12103-6
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849763594250485760
author Tomoatsu Ikeya
Tadashi Ashizawa
Akari Kanematsu
Chie Maeda
Akira Iizuka
Kazue Yamashita
Haruo Miyata
Yasufumi Kikuchi
Kouji Maruyama
Mamoru Ito
Ken Yamaguchi
Yasuto Akiyama
author_facet Tomoatsu Ikeya
Tadashi Ashizawa
Akari Kanematsu
Chie Maeda
Akira Iizuka
Kazue Yamashita
Haruo Miyata
Yasufumi Kikuchi
Kouji Maruyama
Mamoru Ito
Ken Yamaguchi
Yasuto Akiyama
author_sort Tomoatsu Ikeya
collection DOAJ
description Abstract Although triple-negative breast cancers are still challenging to treat, the development of novel neoadjuvant chemotherapy combined with immune checkpoint antibodies is promising. Our group developed the small compound-based anti-PD-1/PD-L1 inhibitor SCL-1 and reported its potent anti-tumor effects on various syngeneic mouse tumors. We herein investigated the efficacy of SCL-1 using an in vivo humanized NOG mouse system. We established a humanized mouse system using double major histocompatibility complex-knockout NOG mice transplanted with MDA-MB231 breast cancer cells and HLA-matched human PBMCs. Tumor-infiltrating lymphocytes (TILs) were analyzed using flow cytometry and real-time PCR. An RNA-sequencing analysis (RNA-seq) of SCL-1-treated MDA-MB231 tumors was performed to identify differentially expressed genes. Orally administered SCL-1 exerted potent anti-tumor effects with > 50% reduction in tumor sizes, which were dependent on PD-L1 expression and T-cell infiltration. Its effects were significantly stronger than those of nivolumab or atezolizumab. A TIL analysis revealed effector CD8+ T cells expressing cytotoxic markers and exhausted markers as well as increases in NK cells and B cells. RNA-seq showed the up-regulated expression of tumor-specific long non-coding (lnc) RNAs in SCL-1-treated tumor tissues, some of which exhibited high HLA-binding activity. SCL-1 exerted strong tumor growth inhibitory effects that were mediated by effector T-cell induction inside tumors and the up-regulated expression of lncRNAs as neoantigens leading to CTL activation. The up-regulated expression of lncRNAs in SCL-1-treated MDA-MB231 tumors is a novel result and may be one of the mechanisms responsible for the anti-tumor efficacy of SCL-1.
format Article
id doaj-art-ba7af6d90ca94a888916d5864c8dc56b
institution DOAJ
issn 2045-2322
language English
publishDate 2025-07-01
publisher Nature Portfolio
record_format Article
series Scientific Reports
spelling doaj-art-ba7af6d90ca94a888916d5864c8dc56b2025-08-20T03:05:21ZengNature PortfolioScientific Reports2045-23222025-07-0115111110.1038/s41598-025-12103-6Impact of the PD-1/PD-L1 inhibitor SCL-1 on MDA-MB231 tumor growth in a humanized MHC-double knockout NOG mouse modelTomoatsu Ikeya0Tadashi Ashizawa1Akari Kanematsu2Chie Maeda3Akira Iizuka4Kazue Yamashita5Haruo Miyata6Yasufumi Kikuchi7Kouji Maruyama8Mamoru Ito9Ken Yamaguchi10Yasuto Akiyama11Immunotherapy Division, Shizuoka Cancer Center Research InstituteImmunotherapy Division, Shizuoka Cancer Center Research InstituteExperimental Animal Facility, Shizuoka Cancer Center Research InstituteImmunotherapy Division, Shizuoka Cancer Center Research InstituteImmunotherapy Division, Shizuoka Cancer Center Research InstituteImmunotherapy Division, Shizuoka Cancer Center Research InstituteImmunotherapy Division, Shizuoka Cancer Center Research InstituteImmunotherapy Division, Shizuoka Cancer Center Research InstituteExperimental Animal Facility, Shizuoka Cancer Center Research InstituteCentral Institute for Experimental Medicine and Life ScienceOffice of the President Emeritus, Shizuoka Cancer CenterImmunotherapy Division, Shizuoka Cancer Center Research InstituteAbstract Although triple-negative breast cancers are still challenging to treat, the development of novel neoadjuvant chemotherapy combined with immune checkpoint antibodies is promising. Our group developed the small compound-based anti-PD-1/PD-L1 inhibitor SCL-1 and reported its potent anti-tumor effects on various syngeneic mouse tumors. We herein investigated the efficacy of SCL-1 using an in vivo humanized NOG mouse system. We established a humanized mouse system using double major histocompatibility complex-knockout NOG mice transplanted with MDA-MB231 breast cancer cells and HLA-matched human PBMCs. Tumor-infiltrating lymphocytes (TILs) were analyzed using flow cytometry and real-time PCR. An RNA-sequencing analysis (RNA-seq) of SCL-1-treated MDA-MB231 tumors was performed to identify differentially expressed genes. Orally administered SCL-1 exerted potent anti-tumor effects with > 50% reduction in tumor sizes, which were dependent on PD-L1 expression and T-cell infiltration. Its effects were significantly stronger than those of nivolumab or atezolizumab. A TIL analysis revealed effector CD8+ T cells expressing cytotoxic markers and exhausted markers as well as increases in NK cells and B cells. RNA-seq showed the up-regulated expression of tumor-specific long non-coding (lnc) RNAs in SCL-1-treated tumor tissues, some of which exhibited high HLA-binding activity. SCL-1 exerted strong tumor growth inhibitory effects that were mediated by effector T-cell induction inside tumors and the up-regulated expression of lncRNAs as neoantigens leading to CTL activation. The up-regulated expression of lncRNAs in SCL-1-treated MDA-MB231 tumors is a novel result and may be one of the mechanisms responsible for the anti-tumor efficacy of SCL-1.https://doi.org/10.1038/s41598-025-12103-6Immune checkpoint inhibitorPD-1/PD-L1Triple-negative breast cancerNOG mouseHumanized mouse
spellingShingle Tomoatsu Ikeya
Tadashi Ashizawa
Akari Kanematsu
Chie Maeda
Akira Iizuka
Kazue Yamashita
Haruo Miyata
Yasufumi Kikuchi
Kouji Maruyama
Mamoru Ito
Ken Yamaguchi
Yasuto Akiyama
Impact of the PD-1/PD-L1 inhibitor SCL-1 on MDA-MB231 tumor growth in a humanized MHC-double knockout NOG mouse model
Scientific Reports
Immune checkpoint inhibitor
PD-1/PD-L1
Triple-negative breast cancer
NOG mouse
Humanized mouse
title Impact of the PD-1/PD-L1 inhibitor SCL-1 on MDA-MB231 tumor growth in a humanized MHC-double knockout NOG mouse model
title_full Impact of the PD-1/PD-L1 inhibitor SCL-1 on MDA-MB231 tumor growth in a humanized MHC-double knockout NOG mouse model
title_fullStr Impact of the PD-1/PD-L1 inhibitor SCL-1 on MDA-MB231 tumor growth in a humanized MHC-double knockout NOG mouse model
title_full_unstemmed Impact of the PD-1/PD-L1 inhibitor SCL-1 on MDA-MB231 tumor growth in a humanized MHC-double knockout NOG mouse model
title_short Impact of the PD-1/PD-L1 inhibitor SCL-1 on MDA-MB231 tumor growth in a humanized MHC-double knockout NOG mouse model
title_sort impact of the pd 1 pd l1 inhibitor scl 1 on mda mb231 tumor growth in a humanized mhc double knockout nog mouse model
topic Immune checkpoint inhibitor
PD-1/PD-L1
Triple-negative breast cancer
NOG mouse
Humanized mouse
url https://doi.org/10.1038/s41598-025-12103-6
work_keys_str_mv AT tomoatsuikeya impactofthepd1pdl1inhibitorscl1onmdamb231tumorgrowthinahumanizedmhcdoubleknockoutnogmousemodel
AT tadashiashizawa impactofthepd1pdl1inhibitorscl1onmdamb231tumorgrowthinahumanizedmhcdoubleknockoutnogmousemodel
AT akarikanematsu impactofthepd1pdl1inhibitorscl1onmdamb231tumorgrowthinahumanizedmhcdoubleknockoutnogmousemodel
AT chiemaeda impactofthepd1pdl1inhibitorscl1onmdamb231tumorgrowthinahumanizedmhcdoubleknockoutnogmousemodel
AT akiraiizuka impactofthepd1pdl1inhibitorscl1onmdamb231tumorgrowthinahumanizedmhcdoubleknockoutnogmousemodel
AT kazueyamashita impactofthepd1pdl1inhibitorscl1onmdamb231tumorgrowthinahumanizedmhcdoubleknockoutnogmousemodel
AT haruomiyata impactofthepd1pdl1inhibitorscl1onmdamb231tumorgrowthinahumanizedmhcdoubleknockoutnogmousemodel
AT yasufumikikuchi impactofthepd1pdl1inhibitorscl1onmdamb231tumorgrowthinahumanizedmhcdoubleknockoutnogmousemodel
AT koujimaruyama impactofthepd1pdl1inhibitorscl1onmdamb231tumorgrowthinahumanizedmhcdoubleknockoutnogmousemodel
AT mamoruito impactofthepd1pdl1inhibitorscl1onmdamb231tumorgrowthinahumanizedmhcdoubleknockoutnogmousemodel
AT kenyamaguchi impactofthepd1pdl1inhibitorscl1onmdamb231tumorgrowthinahumanizedmhcdoubleknockoutnogmousemodel
AT yasutoakiyama impactofthepd1pdl1inhibitorscl1onmdamb231tumorgrowthinahumanizedmhcdoubleknockoutnogmousemodel