A Top-Down Design Approach for Generating a Peptide PROTAC Drug Targeting Androgen Receptor for Androgenetic Alopecia Therapy.

While large-scale artificial intelligence (AI) models for protein structure prediction and design are advancing rapidly, the translation of deep learning models for practical macromolecular drug development remains limited. This investigation aims to bridge this gap by combining cutting-edge methodologies to create a novel peptide-based PROTAC drug development paradigm. Using ProteinMPNN and RFdiffusion, we identified binding peptides for androgen receptor (AR) and Von Hippel-Lindau (VHL), followed by computational modeling with Alphafold2-multimer and ZDOCK to predict spatial interrelationships. Experimental validation confirmed the designed peptide's binding ability to AR and VHL. Transdermal microneedle patching technology was seamlessly integrated for the peptide PROTAC drug delivery in androgenic alopecia treatment. In summary, our approach provides a generic method for generating peptide PROTACs and offers a practical application for designing potential therapeutic drugs for androgenetic alopecia. This showcases the potential of interdisciplinary approaches in advancing drug development and personalized medicine.

CK2-dependent degradation of CBX3 dictates replication fork stalling and PARP inhibitor sensitivity.

DNA replication is a vulnerable cellular process, and its deregulation leads to genomic instability. Here, we demonstrate that chromobox protein homolog 3 (CBX3) binds replication protein A 32-kDa subunit (RPA2) and regulates RPA2 retention at stalled replication forks. CBX3 is recruited to stalled replication forks by RPA2 and inhibits ring finger and WD repeat domain 3 (RFWD3)-facilitated replication restart. Phosphorylation of CBX3 at serine-95 by casein kinase 2 (CK2) kinase augments cadherin 1 (CDH1)-mediated CBX3 degradation and RPA2 dynamics at stalled replication forks, which permits replication fork restart. Increased expression of CBX3 due to gene amplification or CK2 inhibitor treatment sensitizes prostate cancer cells to poly(ADP-ribose) polymerase (PARP) inhibitors while inducing replication stress and DNA damage. Our work reveals CBX3 as a key regulator of RPA2 function and DNA replication, suggesting that CBX3 could serve as an indicator for targeted therapy of cancer using PARP inhibitors.

Development of a PAK4-targeting PROTAC for renal carcinoma therapy: concurrent inhibition of cancer cell proliferation and enhancement of immune cell response.

BACKGROUND: Finding the oncogene, which was able to inhibit tumor cells intrinsically and improve the immune answers, will be the future direction for renal cancer combined treatment. Following patient sample analysis and signaling pathway examination, we propose p21-activated kinase 4 (PAK4) as a potential target drug for kidney cancer. PAK4 exhibits high expression levels in patient samples and plays a regulatory role in the immune microenvironment. METHODS: Utilizing AI software for peptide drug design, we have engineered a specialized peptide proteolysis targeting chimera (PROTAC) drug with selectivity for PAK4. To address challenges related to drug delivery, we developed a nano-selenium delivery system for efficient transport of the peptide PROTAC drug, termed PpD (PAK4 peptide degrader). FINDINGS: We successfully designed a peptide PROTAC drug targeting PAK4. PpD effectively degraded PAK4 with high selectivity, avoiding interference with other homologous proteins. PpD significantly attenuated renal carcinoma proliferation in vitro and in vivo. Notably, PpD demonstrated a significant inhibitory effect on tumor proliferation in a fully immunocompetent mouse model, concomitantly enhancing the immune cell response. Moreover, PpD demonstrated promising tumor growth inhibitory effects in mini-PDX and PDO models, further underscoring its potential for clinical application. INTERPRETATION: This PAK4-targeting peptide PROTAC drug not only curtails renal cancer cell proliferation but also improves the immune microenvironment and enhances immune response. Our study paves the way for innovative targeted therapies in the management of renal cancer. FUNDING: This work is supported by Research grants from non-profit organizations, as stated in the Acknowledgments.

Development of a Double-Stapled Peptide Stabilizing Both α-Helix and ß-Sheet Structures for Degrading Transcription Factor AR-V7.

Peptide drugs offer distinct advantages in therapeutics; however, their limited stability and membrane penetration abilities hinder their widespread application. One strategy to overcome these challenges is the hydrocarbon peptide stapling technique, which addresses issues such as poor conformational stability, weak proteolytic resistance, and limited membrane permeability. Nonetheless, while peptide stapling has successfully stabilized α-helical peptides, it has shown limited applicability for most ß-sheet peptide motifs. In this study, we present the design of a novel double-stapled peptide capable of simultaneously stabilizing both α-helix and ß-sheet structures. Our designed double-stapled peptide, named DSARTC, specifically targets the androgen receptor (AR) DNA binding domain and MDM2 as E3 ligase. Serving as a peptide-based PROTAC (proteolysis-targeting chimera), DSARTC exhibits the ability to degrade both the full-length AR and AR-V7. Molecular dynamics simulations and circular dichroism analysis validate the successful constraint of both secondary structures, demonstrating that DSARTC is a "first-in-class" heterogeneous-conformational double-stapled peptide drug candidate. Compared to its linear counterpart, DSARTC displays enhanced stability and an improved cell penetration ability. In an enzalutamide-resistant prostate cancer animal model, DSARTC effectively inhibits tumor growth and reduces the levels of both AR and AR-V7 proteins. These results highlight the potential of DSARTC as a more potent and specific peptide PROTAC for AR-V7. Furthermore, our findings provide a promising strategy for expanding the design of staple peptide-based PROTAC drugs, targeting a wide range of "undruggable" transcription factors.

MYC induces CDK4/6 inhibitors resistance by promoting pRB1 degradation.

CDK4/6 inhibitors (CDK4/6i) show anticancer activity in certain human malignancies, such as breast cancer. However, their application to other tumor types and intrinsic resistance mechanisms are still unclear. Here, we demonstrate that MYC amplification confers resistance to CDK4/6i in bladder, prostate and breast cancer cells. Mechanistically, MYC binds to the promoter of the E3 ubiquitin ligase KLHL42 and enhances its transcription, leading to RB1 deficiency by inducing both phosphorylated and total pRB1 ubiquitination and degradation. We identify a compound that degrades MYC, A80.2HCl, which induces MYC degradation at nanomolar concentrations, restores pRB1 protein levels and re-establish sensitivity of MYC high-expressing cancer cells to CDK4/6i. The combination of CDK4/6i and A80.2HCl result in marked regression in tumor growth in vivo. Altogether, these results reveal the molecular mechanisms underlying MYC-induced resistance to CDK4/6i and suggest the utilization of the MYC degrading molecule A80.2HCl to potentiate the therapeutic efficacy of CDK4/6i.

High-fat diet promotes liver tumorigenesis via palmitoylation and activation of AKT.

OBJECTIVE: Whether and how the PI3K-AKT pathway, a central node of metabolic homeostasis, is responsible for high-fat-induced non-alcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC) remain a mystery. Characterisation of AKT regulation in this setting will provide new strategies to combat HCC. DESIGN: Metabolite library screening disclosed that palmitic acid (PA) could activate AKT. In vivo and in vitro palmitoylation assay were employed to detect AKT palmitoylation. Diverse cell and mouse models, including generation of AKT1C77S and AKT1C224S knock-in cells, Zdhhc17 and Zdhhc24 knockout mice and Akt1C224S knock-in mice were employed. Human liver tissues from patients with NASH and HCC, hydrodynamic transfection mouse model, high-fat/high-cholesterol diet (HFHCD)-induced NASH/HCC mouse model and high-fat and methionine/choline-deficient diet (HFMCD)-induced NASH mouse model were also further explored for our mechanism studies. RESULTS: By screening a metabolite library, PA has been defined to activate AKT by promoting its palmitoyl modification, an essential step for growth factor-induced AKT activation. Biologically, a high-fat diet could promote AKT kinase activity, thereby promoting NASH and liver cancer. Mechanistically, palmitoyl binding anchors AKT to the cell membrane in a PIP3-independent manner, in part by preventing AKT from assembling into an inactive polymer. The palmitoyltransferases ZDHHC17/24 were characterised to palmitoylate AKT to exert oncogenic effects. Interestingly, the anti-obesity drug orlistat or specific penetrating peptides can effectively attenuate AKT palmitoylation and activation by restricting PA synthesis or repressing AKT modification, respectively, thereby antagonising liver tumorigenesis. CONCLUSIONS: Our findings elucidate a novel fine-tuned regulation of AKT by PA-ZDHHC17/24-mediated palmitoylation, and highlight tumour therapeutic strategies by taking PA-restricted diets, limiting PA synthesis, or directly targeting AKT palmitoylation.

Knocking down AR promotes osteoblasts to recruit prostate cancer cells by altering exosomal circ-DHPS/miR-214-3p/CCL5 pathway.

ABSTRACT: Tumor-derived exosomes have been shown to play a key role in organ-specific metastasis, and the androgen receptor regulates prostate cancer (PCa) progression. It is unclear whether the androgen receptor regulates the recruitment of prostate cancer cells to the bone microenvironment, even bone metastases, through exosomes. Here, we found that exosomes isolated from PCa cells after knocking down androgen receptor (AR) or enzalutamide treatment can facilitate the migration of prostate cancer cells to osteoblasts. In addition, AR silencing or treatment with the AR antagonist enzalutamide may increase the expression of circular RNA-deoxyhypusine synthase (circ-DHPS) in PCa cells, which can be transported to osteoblasts by exosomes. Circ-DHPS acts as a competitive endogenous RNA (ceRNA) against endogenous miR-214-3p to promote C-C chemokine ligand 5 (CCL5) levels in osteoblasts. Increasing the level of CCL5 in osteoblasts could recruit more PCa cells into the bone microenvironment. Thus, blocking the circ-DHPS/miR-214-3p/CCL5 signal may decrease exosome-mediated migration of prostate cancer cells to osteoblasts.

Targeting LYPLAL1-mediated cGAS depalmitoylation enhances the response to anti-tumor immunotherapy.

Cyclic GMP-AMP synthase (cGAS) binds pathogenic and other cytoplasmic double-stranded DNA (dsDNA) to catalyze the synthesis of cyclic GMP-AMP (cGAMP), which serves as the secondary messenger to activate the STING pathway and innate immune responses. Emerging evidence suggests that activation of the cGAS pathway is crucial for anti-tumor immunity; however, no effective intervention method targeting cGAS is currently available. Here we report that cGAS is palmitoylated by ZDHHC9 at cysteines 404/405, which promotes the dimerization and activation of cGAS. We further identified that lysophospholipase-like 1 (LYPLAL1) depalmitoylates cGAS to compromise its normal function. As such, inhibition of LYPLAL1 significantly enhances cGAS-mediated innate immune response, elevates PD-L1 expression, and enhances anti-tumor response to PD-1 blockade. Our results therefore reveal that targeting LYPLAL1-mediated cGAS depalmitoylation contributes to cGAS activation, providing a potential strategy to augment the efficacy of anti-tumor immunotherapy.

Emerging role of ubiquitination/deubiquitination modification of PD-1/PD-L1 in cancer immunotherapy.

As members of the immune checkpoint family, PD-1 and its ligand PD-L1 play critical roles in maintaining the balance between autoimmunity and tolerance. The interaction of PD-1/PD-L1 is also involved in tumor evasion inside the tumor microenvironment, caused by reduced T cell activation, proliferation, cytotoxic secretion, and survival. Previous research has shown that the expression level of PD-1/PD-L1 may be regulated by ubiquitin-mediated proteasome degradation, which is an important mode of post-translational modification (PTM). PD-1/PD-L1 ubiquitin modification research in tumor immunotherapy is the subject of the present review, which aims to assess the most recent developments in this area. We offer a short explanation of PD-1/PD-L1 as well as some basic background information on the UPS system and discuss many routes that target E3s and DUBs, respectively, in the regulation of PD-1/PD-L1 in tumor immunotherapy. In addition, we offer numerous innovative prospective research areas for the future, as well as novel immunotherapy concepts and ideas. Taken together, the information compiled herein should serve as a comprehensive repository of information about tumor immunotherapy that is currently available, and it should be useful in the design of future studies, as well as the development of potential targets and strategies for future tumor immunotherapy.

TRABID overexpression enables synthetic lethality to PARP inhibitor via prolonging 53BP1 retention at double-strand breaks.

53BP1 promotes nonhomologous end joining (NHEJ) over homologous recombination (HR) repair by mediating inactivation of DNA end resection. Ubiquitination plays an important role in regulating dissociation of 53BP1 from DNA double-strand breaks (DSBs). However, how this process is regulated remains poorly understood. Here, we demonstrate that TRABID deubiquitinase binds to 53BP1 at endogenous level and regulates 53BP1 retention at DSB sites. TRABID deubiquitinates K29-linked polyubiquitination of 53BP1 mediated by E3 ubiquitin ligase SPOP and prevents 53BP1 dissociation from DSBs, consequently inducing HR defects and chromosomal instability. Prostate cancer cells with TRABID overexpression exhibit a high sensitivity to poly (ADP-ribose) polymerase (PARP) inhibitors. Our work shows that TRABID facilitates NHEJ repair over HR during DNA repair by inducing prolonged 53BP1 retention at DSB sites, suggesting that TRABID overexpression may predict HR deficiency and the potential therapeutic use of PARP inhibitors in prostate cancer.

ß-Ionone represses renal cell carcinoma progression through activating LKB1/AMPK-triggered autophagy.

ß-Ionone, the end ring analog of ß-carotenoids, has been proven to have an antitumor effect in a variety of cancers. In this study, we investigated the impact of ß-ionone on renal cell carcinoma (RCC) cell lines (786-O and ACHN) using colony formation assays, flow cytometry analysis, and western blot analysis. We found that ß-ionone effectively inhibited the proliferation of RCC cells in vitro, which was also confirmed in a xenograft model. Moreover, we found that ß-ionone could induce autophagy, as indicated by LC3 puncta in 786-O and ACHN cell lines and the expression of LC3 in ß-ionone-treated RCC cells. To further explore the underlying mechanism, we assessed liver kinase B1/AMP-activated protein kinase (LKB1/AMPK) signaling pathway activity, and the results showed that ß-ionone inhibited the proliferation of RCC cells by inducing autophagy via the LKB1/AMPK signaling pathway. In summary, our findings provide a new therapeutic strategy of ß-ionone-induced autophagy in RCC.

Silibinin inhibits the migration, invasion and epithelial-mesenchymal transition of prostate cancer by activating the autophagic degradation of YAP.

Silibinin (SB), a flavonoid extracted from milk thistle seeds, has been found to exert antitumor effects in numerous tumor types. Our previous study reported that SB had anti-metastatic effects in prostate cancer (PCa). However, the exact underlying molecular mechanisms remain to be determined. The present study aimed to investigate the effects of SB on the migration, invasion and epithelial-mesenchymal transition (EMT) of castration-resistant PCa (CRPC) cells using wound healing, Transwell assays, and western blotting. The results revealed that SB treatment significantly inhibited the migration and invasion of CRPC cell lines. Moreover, SB was confirmed to activate autophagy, as determined using LC3 conversion, LC3 turnover and LC3 puncta assays. Further mechanistic studies indicated that the expression levels of Yes-associated protein (YAP) were downregulated in an autophagy-dependent manner after SB treatment. In addition, the SB-induced autophagic degradation of YAP was associated with the anti-metastatic effects of SB in CRPC. In conclusion, the findings of the present study suggested that SB might inhibit the migration, invasion and EMT of PCa cells by regulating the autophagic degradation of YAP, thus representing a potential novel treatment strategy for metastatic CRPC.

Deubiquitinase OTUD5 modulates mTORC1 signaling to promote bladder cancer progression.

The mechanistic (formally "mammalian") target of rapamycin (mTOR) pathway serves as a crucial regulator of various biological processes such as cell growth and cancer progression. In bladder cancer, recent discoveries showing the cancer-promoting role of mTOR complex 1 have attracted wide attention. However, the regulation of mTOR signaling in bladder cancer is complicated and the underlying mechanism remains elusive. Here, we report that the deubiquitinating enzyme, ovarian tumor domain-containing protein 5 (OTUD5), can activate the mTOR signaling pathway, promote cancer progression, and show its oncogenic potential in bladder cancer. In our study, we found that OTUD5 deubiquitinated a RING-type E3 ligase, RNF186, and stabilized its function. In addition, the stabilization of RNF186 further led to the degradation of sestrin2, which is an inhibitor of the mTOR signaling pathway. Together, we provide novel insights into the pathogenesis of bladder cancer and first prove that OTUD5 can promote bladder cancer progression through the OTUD5-RNF186-sestrin2-mTOR axis, which may be exploited in the future for the diagnosis and treatment of this malignancy.

Capsaicin inhibits the migration, invasion and EMT of renal cancer cells by inducing AMPK/mTOR-mediated autophagy.

Capsaicin (CAP), extracted from Capsicum fruits, has been reported to exhibit antitumor effects in various lines of cancer cells. However, the mechanism underlying its antitumor efficiency is not fully understood. Autophagy is a fundamental self-degradation process of cells that maintains homeostasis and plays a controversial role in tumor initiation and progression. The EMT is defined as a system regulating cells transformed from an epithelial-like phenotype into a mesenchymal phenotype by several internal and external factors, following the metastatic performance of the cells developed. The present study aimed to investigate the potential role of autophagy in CAP-induced antitumor effects in renal cell carcinoma (RCC) 786-O and CAKI-1 cell lines. The results revealed that CAP remarkably inhibited the migration and invasion of RCC cells in vitro and metastasis in vivo. Moreover, we found that the CAP treatment increased the formation of autophagolysosome vacuoles and LC3 yellow and red fluorescent puncta in RCC cells and upregulated the expression of LC3, suggesting that autophagy was induced by CAP in 786-O and CAKI-1 cell lines. Our further results demonstrated that CAP-induced autophagy was mediated by the AMPK/mTOR pathway. In conclusion, our study provides new knowledge of the potential relationship between autophagy and metastasis inhibition induced by CAP, which might be a promising therapeutic strategy in RCC.

De Novo Design of an Androgen Receptor DNA Binding Domain-Targeted peptide PROTAC for Prostate Cancer Therapy.

Androgen receptor splice variant-7 (AR-V7), one of the major driving factors, is the most attractive drug target in castration-resistant prostate cancer (CRPC). Currently, no available drugs efficiently target AR-V7 in clinical practice. The DNA binding domain (DBD) is indispensable for the transcriptional activity of AR full length and AR splice variants, including AR-V7. Based on the homodimerization structure of the AR DBD, a novel peptide-based proteolysis-targeting chimera (PROTAC) drug is designed to induce AR and AR-V7 degradation in a DBD and MDM2-dependent manner, without showing any activity on other hormone receptors. To overcome the short half-life and poor cell penetrability of peptide PROTAC drugs, an ultrasmall gold (Au)-peptide complex platform to deliver the AR DBD PROTAC in vivo is developed. The obtained Au-AR pep-PROTAC effectively degrades AR and AR-V7 in prostate cancer cell lines, particularly in CWR22Rv1 cells with DC50 values 48.8 and 79.2 nM, respectively. Au-AR pep-PROTAC results in suppression of AR levels and induces tumor regression in both enzalutamide sensitive and resistant prostate cancer animal models. Further optimization of the Au-AR pep-PROTAC can ultimately lead to a new therapy for AR-V7-positive CRPC.

ERK1/2 inhibits Cullin 3/SPOP-mediated PrLZ ubiquitination and degradation to modulate prostate cancer progression.

The gene encoding the E3 ubiquitin ligase substrate-binding adaptor SPOP is frequently mutated in prostate cancer (PCa), but how SPOP functions as a tumor suppressor and contributes to PCa pathogenesis remains poorly understood. Prostate Leucine Zipper (PrLZ) serves as a prostate-specific and androgen-responsive gene, which plays a pivotal role in the malignant progression of PCa. However, the upstream regulatory mechanism of PrLZ protein stability and its physiological contribution to PCa carcinogenesis remain largely elusive. Here we report that PrLZ can be degraded by SPOP. PrLZ abundance is elevated in SPOP-mutant expressing PCa cell lines and patient specimens. Meanwhile, ERK1/2 might regulate SPOP-mediated PrLZ degradation through phosphorylating PrLZ at Ser40, which blocks the interaction between SPOP and PrLZ. In addition, we identify IL-6 might act as an upstream PrLZ degradation regulator via promoting its phosphorylation by ERK1/2, leading to its impaired recognition by SPOP. Thus, our study reveals a novel SPOP substrate PrLZ which might be controlled by ERK1/2-mediated phosphorylation, thereby facilitating to explore novel drug targets and improve therapeutic strategy for PCa.

ß-ionone Inhibits Epithelial-Mesenchymal Transition (EMT) in Prostate Cancer Cells by Negatively Regulating the Wnt/ß-Catenin Pathway.

BACKGROUND: ß-ionone is a terminal cyclic analog of beta-carotenoids widely found in plants. In recent years, accumulating evidence has shown that ß-ionone exerts antitumor effects on various malignant tumors. However, limited studies have revealed the role of ß-ionone in regulating the epithelial-mesenchymal transition (EMT) of prostate cancer (PCa) cells. This study aimed to investigate the effect of ß-ionone on the EMT process of PCa, focusing on Wnt/ß-catenin signaling pathway. METHODS: After exposure to ß-ionone, cell viability was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the Brdu proliferation assay. The Transwell and wounding healing were used to investigate the migration and invasion abilities of PCa cells. Expression of proteins involved in the EMT process (E-cadherin, N-cadherin, vimentin) and proteins in the Wnt/ß-catenin pathway (ß-catenin, GSK3-ß, and p-GSK3-ß) were explored by western blotting. The effects of ß-ionone on ß-catenin degradation were explored by cycloheximide tracking assay and in vitro ubiquitination assay. Nude mouse xenograft model was served as the model system in vivo. RESULTS: The migration, invasion, and EMT process of PCa Human PC-3 prostate adenocarcinoma cells (PC3) and Human 22RV1 prostate adenocarcinoma cells (22RV1) cells were significantly inhibited after ß-ionone treatment. In addition, ß-ionone also inhibited the growth and EMT process of subcutaneous xenograft tumors in nude mice. The study also found that ß-catenin, which promotes EMT, was downregulated after ß-ionone treatment. Further mechanistic studies revealed that ß-ionone inhibited the Wnt/ß-catenin pathway by accelerating the ubiquitination and degradation of ß-catenin in PCa, thus inhibiting the downstream migration, invasion, and EMT processes. CONCLUSIONS: These findings demonstrate that ß-ionone may be a potential natural compound targeting the Wnt/ß-catenin pathway for the treatment of PCa.

Acetylation-dependent regulation of TPD52 isoform 1 modulates chaperone-mediated autophagy in prostate cancer.

Aberrant chaperone-mediated autophagy (CMA) activation has been suggested as a tumorigenesis-promoting event in various cancers, although its roles in prostate cancer (PCa) remain elusive. Emerging evidence indicates that TPD52 isoform 1, a prostate-specific and androgen-responsive gene, contributes to the malignant progression of PCa. Here, we demonstrate that TPD52 enhances CMA activation by interacting with HSPA8/HSC70 and enhancing substrate degradation in PCa. Elevation of TPD52 is essential for CMA-induced PCa cell proliferation and stress resistance in vitro and in vivo. Furthermore, TPD52 is acetylated by KAT2B at K163, which is a process that can be antagonized by HDAC2. Inactivation of HDAC2 results in elevated TPD52 acetylation, which compromises the interaction between TPD52 and HSPA8, leading to impaired CMA function and tumor growth in vivo. Taken together, our findings reveal that acetylation-dependent regulation of TPD52 modulates CMA oncogenic function in PCa, thereby suggesting the possibility of targeting the TPD52-mediated CMA pathway to control the progression of PCa.Abbreviations: CMA: chaperone-mediated autophagy; HDAC2: histone deacetylase 2; HSPA8/HSC70: heat shock protein family A (Hsp70) member 8; KAT2B: lysine acetyltransferase 2B; LAMP2A: lysosomal associated membrane protein 2A; PCa: prostate cancer; TPD52: tumor protein D52.

OTUD5-mediated deubiquitination of YAP in macrophage promotes M2 phenotype polarization and favors triple-negative breast cancer progression.

Macrophages, which are highly plastic, can be polarized to M1 or M2 subtypes according to the diverse signals in complex microenvironment. Studies have shown the activation of YAP, an oncogenic transcriptional co-activator, increased macrophage recruitment. However, its role in macrophage polarization remains to be elucidated, especially in triple-negative breast cancer (TNBC) progression. Here we found TNBC cells increased YAP expression in macrophages, which depended on OTUD5-mediated deubiquitination and stabilization of YAP, then the high expression of YAP polarized macrophage to the M2-like phenotype. Moreover, the elevation of YAP in M2-like macrophage promotes the pro-metastatic potential of TNBC cells via MCP-1/CCR2 pathway. We also observed high expression of YAP in M2 macrophage was negatively related to survival. Collectively, our finding suggested the therapeutic strategy that targets YAP+ M2 macrophage could be a novel option for TNBC treatment.

Acetylation-dependent regulation of PD-L1 nuclear translocation dictates the efficacy of anti-PD-1 immunotherapy.

Immunotherapies that target programmed cell death protein 1 (PD-1) and its ligand PD-L1 as well as cytotoxic T-lymphocyte-associated protein 4 (CTLA4) have shown impressive clinical outcomes for multiple tumours. However, only a subset of patients achieves durable responses, suggesting that the mechanisms of the immune checkpoint pathways are not completely understood. Here, we report that PD-L1 translocates from the plasma membrane into the nucleus through interactions with components of the endocytosis and nucleocytoplasmic transport pathways, regulated by p300-mediated acetylation and HDAC2-dependent deacetylation of PD-L1. Moreover, PD-L1 deficiency leads to compromised expression of multiple immune-response-related genes. Genetically or pharmacologically modulating PD-L1 acetylation blocks its nuclear translocation, reprograms the expression of immune-response-related genes and, as a consequence, enhances the anti-tumour response to PD-1 blockade. Thus, our results reveal an acetylation-dependent regulation of PD-L1 nuclear localization that governs immune-response gene expression, and thereby advocate targeting PD-L1 translocation to enhance the efficacy of PD-1/PD-L1 blockade.