Membrane fusogenic nanoparticle-based HLA-peptide-addressing universal T cell receptor-engineered T (HAUL TCR-T) cell therapy in solid tumor.

T cell receptor-engineered T (TCR-T) cell therapy has demonstrated therapeutic effects in basic research and clinical trials for treating solid tumors. Due to the peptide-dependent recognition and the human leukocyte antigen (HLA)-restriction, TCR-T cell therapy is generally custom designed to target individual antigens. The lack of suitable universal targets for tumor cells significantly limits its clinical applications. Establishing a universal TCR-T treatment strategy is of great significance. This study designed and evaluated the HLA-peptide-addressing universal (HAUL) TCR-T cell therapy based on HLA-peptide (pHLA) loaded membrance fusogenic deliver system. The pHLA-NP-based tumor cell membrane modification technology can transfer the pHLA onto the surface of tumor cells through membrane fusogenic nanoparticles. Then tumor cells are recognized and killed by TCR-T cells specifically. The HAUL TCR-T cell therapy technology is a universal technology that enables tumor cells to be identified and killed by specific TCR-T cells, regardless of the HLA typing of tumor cells.

A novel mesenchymal stem cell-based regimen for acute myeloid leukemia differentiation therapy.

Currently the main treatment of acute myeloid leukemia (AML) is chemotherapy combining hematopoietic stem cell transplantation. However, the unbearable side effect of chemotherapy and the high risk of life-threatening infections and disease relapse following hematopoietic stem cell transplantation restrict its application in clinical practice. Thus, there is an urgent need to develop alternative therapeutic tactics with significant efficacy and attenuated adverse effects. Here, we revealed that umbilical cord-derived mesenchymal stem cells (UC-MSC) efficiently induced AML cell differentiation by shuttling the neutrophil elastase (NE)-packaged extracellular vesicles (EVs) into AML cells. Interestingly, the generation and release of NE-packaged EVs could be dramatically increased by vitamin D receptor (VDR) activation in UC-MSC. Chemical activation of VDR by using its agonist 1α,25-dihydroxyvitamin D3 efficiently enhanced the pro-differentiation capacity of UC-MSC and then alleviated malignant burden in AML mouse model. Based on these discoveries, to evade the risk of hypercalcemia, we synthetized and identified sw-22, a novel non-steroidal VDR agonist, which exerted a synergistic pro-differentiation function with UC-MSC on mitigating the progress of AML. Collectively, our findings provided a non-gene editing MSC-based therapeutic regimen to overcome the differentiation blockade in AML.

Efficacy evaluation of chimeric antigen receptor-modified human peritoneal macrophages in the treatment of gastric cancer.

BACKGROUND: Gastric cancer is one of the most common cancers. Peritoneal carcinomatosis (PC) appears to be the most common pattern of recurrence, and more than half of the GC patients eventually die from PC. Novel strategies for the management of patients with PC are urgently needed. Recently, rapid progress has been made in adoptive transfer therapy by using macrophages as the effector cells due to their capabilities of phagocytosis, antigen presentation, and high penetration. Here, we generated a novel macrophage-based therapy and investigated anti-tumoral effects on GC and potential toxicity. METHODS: We developed a novel Chimeric Antigen Receptor-Macrophage (CAR-M) based on genetically modifying human peritoneal macrophages (PMs), expressing a HER2-FcεR1γ-CAR (HF-CAR). We tested HF-CAR macrophages in a variety of GC models in vitro and in vivo. RESULTS: HF-CAR-PMs specifically targeted HER2-expressed GC, and harboured the FcεR1γ moieties to trigger engulfment. Intraperitoneal administration of HF-CAR-PMs significantly facilitated the HER2-positive tumour regression in PC mouse model and prolonged the overall survival rate. In addition, the combined use of oxaliplatin and HF-CAR-PMs exhibited significantly augment anti-tumour activity and survival benefit. CONCLUSIONS: HF-CAR-PMs could represent an exciting therapeutic option for patients with HER2-positive GC cancer, which should be tested in carefully designed clinical trials.

Targeting CD44 Variant 5 with an Antibody-Drug Conjugate Is an Effective Therapeutic Strategy for Intrahepatic Cholangiocarcinoma.

Intrahepatic cholangiocarcinoma (ICC) is the second most frequent type of primary liver cancer. ICC is among the deadliest malignancies, highlighting that novel treatments are urgently needed. Studies have shown that CD44 variant isoforms, rather than the CD44 standard isoform, are selectively expressed in ICC cells, providing an opportunity for the development of an antibody-drug conjugate (ADC)-based targeted therapeutic strategy. In this study, we observed the specific expression of CD44 variant 5 (CD44v5) in ICC tumors. CD44v5 protein was expressed on the surface of most ICC tumors (103 of 155). A CD44v5-targeted ADC, H1D8-DC (H1D8-drug conjugate), was developed that comprises a humanized anti-CD44v5 mAb conjugated to the microtubule inhibitor monomethyl auristatin E (MMAE) via a cleavable valine-citrulline-based linker. H1D8-DC exhibited efficient antigen binding and internalization in cells expressing CD44v5 on the cell surface. Because of the high expression of cathepsin B in ICC cells, the drug was preferentially released in cancer cells but not in normal cells, thus inducing potent cytotoxicity at picomolar concentrations. In vivo studies showed that H1D8-DC was effective against CD44v5-positive ICC cells and induced tumor regression in patient-derived xenograft models, whereas no significant adverse toxicities were observed. These data demonstrate that CD44v5 is a bona fide target in ICC and provide a rationale for the clinical investigation of a CD44v5-targeted ADC-based approach. SIGNIFICANCE: Elevated expression of CD44 variant 5 in intrahepatic cholangiocarcinoma confers a targetable vulnerability using the newly developed antibody-drug conjugate H1D8-DC, which induces potent growth suppressive effects without significant toxicity.

PFKFB4 facilitates palbociclib resistance in oestrogen receptor-positive breast cancer by enhancing stemness.

BACKGROUND: ER+ breast cancer (ER+ BC) is the most common subtype of BC. Recently, CDK4/6 inhibitors combined with aromatase inhibitors have been approved by FDA as the first-line therapy for patients with ER+ BC, and showed promising therapeutic efficacy in clinical treatment. However, resistance to CDK4/6 inhibitors is frequently observed. A better understanding of the drug resistance mechanism is beneficial to improving therapeutic strategies by identifying optimal combinational treatments. METHODS: Western blotting, qPCR, flow cytometry and a series of cell experiments were performed to evaluate the phenotype of MCF-7/R cells. RNA sequencing, non-targeted metabolomics, shRNA knockdown and tumour cell-bearing mouse models were used to clarify the drug resistance mechanism. RESULTS: Here, we found that ER+ BC cells have shown an adaptive resistance to palbociclib-induced cell cycle arrest by activating an alternative signal pathway, independent of the CDK4/6-RB signal transduction. Continuing treatment of palbociclib evoked cellular senescence of ER+ BC cells. Subsequently, the senescence-like phenotype promoted stemness of ER+ BC cells, accompanied by increased chemoresistance and tumour-initiating potential. Based on transcriptome analysis, we found that PFKFB4 played an important role in stemness transformation and drug resistance. A close correlation was determined between PFKFB4 expression by ER+ BC cells and cell senescence and stemness. Mechanistically, metabolomic profiling revealed that PFKFB4 reprogramed glucose metabolism and promoted cell stemness by enhancing glycolysis. Strikingly, diminishing PFKFB4 levels improved drug sensitivity and overcame chemoresistance during palbociclib treatment in ER+ BC. CONCLUSIONS: These findings not only demonstrated the novel mechanism underlying which ER+ BC cells resisted to palbociclib, but also provided a possible therapeutic strategy in the intervention of ER+ BC to overcome drug resistance.

B7-H3 augments the pro-angiogenic function of tumor-associated macrophages and acts as a novel adjuvant target for triple-negative breast cancer therapy.

B7-H3 is an immune checkpoint molecule from the B7 superfamily. It has been widely studied in tumor immune evasion in certain types of cancer. In our preliminary study, we found that B7-H3 is specifically enriched in tumor-associated macrophages (TAMs) in triple-negative breast cancer (TNBC) patients and strongly correlated with poor clinical prognosis. However, the role of B7-H3 in breast cancer remains elusive. Our current study aims to explore the potential of B7-H3 as a novel target in TNBC therapy. Here, we demonstrated that B7-H3 enriched on TAMs is tightly correlated with TNBC clinical progression. B7-H3high TAMs exhibit great pro-metastatic and immunosuppressive functions by intriguing extracellular matrix (ECM) reconstruction and tumor angiogenesis, therefore helping tumor cell dissemination and dampening T-cell infiltration in tumor microenvironment (TME). Importantly, targeting blockade of B7-H3 by anti-B7-H3 antibody improves the tumor vasculature disorder, thereby enhancing chemotherapy and PD-1 therapy efficacy. In conclusion, our study establishes the correlation between B7-H3high TAMs and TNBC progression for the first time. By exploring the possibility of targeting B7-H3 expressed in both tumor cells and TAMs, we suggest that B7-H3 could be a promising target in clinical TNBC treatment.

CDK5 Inhibition Abrogates TNBC Stem-Cell Property and Enhances Anti-PD-1 Therapy.

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, in which the higher frequency of cancer stem cells (CSCs) correlates with the poor clinical outcome. An aberrant activation of CDK5 is found to associate with TNBC progression closely. CDK5 mediates PPARγ phosphorylation at its Ser 273, which induces CD44 isoform switching from CD44s to CD44v, resulting in an increase of stemness of TNBC cells. Blocking CDK5/pho-PPARγ significantly reduces CD44v+ BCSCs population in tumor tissues, thus abrogating metastatic progression in TNBC mouse model. Strikingly, diminishing stemness transformation reverses immunosuppressive microenvironment and enhances anti-PD-1 therapeutic efficacy on TNBC. Mechanistically, CDK5 switches the E3 ubiquitin ligase activity of PPARγ and directly protects ESRP1 from a ubiquitin-dependent proteolysis. This finding firstly indicates that CDK5 blockade can be a potent strategy to diminish stemness transformation and increase the response to PD-1 blockade in TNBC therapy.

Chimeric antigen receptor macrophage therapy for breast tumours mediated by targeting the tumour extracellular matrix.

BACKGROUND: The extracellular matrix (ECM) is essential for malignant tumour progression, as it is a physical barrier to various kinds of anticancer therapies. Matrix metalloproteinase (MMPs) can degrade almost all ECM components, and macrophages are an important source of MMPs. Studies using macrophages to treat tumours have shown that macrophages can enter tumour tissue to play a regulatory role. METHODS: We modified macrophages with a designed chimeric antigen receptor (CAR), which could be activated after recognition of the tumour antigen HER2 to trigger the internal signalling of CD147 and increase the expression of MMPs. RESULTS: Although CAR-147 macrophage treatment did not affect tumour cell growth in vitro compared with control treatment. However, we found that the infusion of CAR-147 macrophages significantly inhibited HER2-4T1 tumour growth in BALB/c mice. Further investigation showed that CAR-147 macrophages could reduce tumour collagen deposition and promote T-cell infiltration into tumours, which were consistent with expectations. Interestingly, the levels of the inflammatory cytokines TNF-α and IL-6, which are key factors in cytokine release syndrome, were significantly decreased in the peripheral blood in CAR-147 macrophage-transfused mice. CONCLUSION: Our data suggest that targeting the ECM by engineered macrophages would be an effective treatment strategy for solid tumours.

BZ-26, a novel GW9662 derivate, attenuated inflammation by inhibiting the differentiation and activation of inflammatory macrophages.

Peroxisome proliferator-activated receptor-gamma (PPARγ) is considered to be an important transcriptional factor in regulation of macrophages differentiation and activation. We have synthesized a series of novel structural molecules based on GW9662's structure (named BZ-24, BZ-25 and BZ-26), and interaction activity was calculated by computational docking. BZ-26 had shown stronger interaction with PPARγ and had higher transcriptional inhibitory activity of PPARγ with lower dosage compared with GW9662. BZ-26 was proved to inhibit inflammatory macrophage differentiation. LPS-induced acute inflammation mouse model was applied to demonstrate its anti-inflammatory activity. And the results showed that BZ-26 administration attenuated plasma tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) secretion, which are vital cytokines in acute inflammation. The anti-inflammatory activity was examined in THP-1 cell line, and TNF-α, IL-6 and MCP-1, were significantly inhibited. The results of Western blot and luciferase reporter assay indicated that BZ-26 not only inhibited NF-κB transcriptional activity, but also abolished LPS-induce nuclear translocation of P65. We also test BZ-26 action in tumor-bearing chronic inflammation mouse model, and BZ-26 was able to alter macrophages phenotype, resulting in antitumor effect. All our data revealed that BZ-26 modulated LPS-induced acute inflammation via inhibiting inflammatory macrophages differentiation and activation, potentially via inhibition of NF-κB signal pathway.

S-nitrosylation of ERK inhibits ERK phosphorylation and induces apoptosis.

Extracellular signal-regulated kinase (ERK) belongs to the mitogen-activated protein kinases (MAPK) superfamily. Aberrant upregulation and activation of ERK cascades may often lead to tumor cell development. However, how ERK is involved in tumor progression is yet to be defined. In current study, we described that ERK undergoes S-nitrosylation by nitric oxide (NO). ERK S-nitrosylation inhibits its phosphorylation and triggers apoptotic program as verified by massive apoptosis in fluorescence staining. The proapoptotic effect of NO induced S-nitrosylation is reversed by NO scavenger Haemoglobin (HB). Furthermore, an S-nitrosylation dead ERK mutant C183A also demolishes the proapoptotic potential of NO and favors cell survival. Therefore, Cys(183) might be a potential S-nitrosylation site in ERK. In addition, S-nitrosylation is a general phenomenon that regulates ERK activity. These findings identify a novel link between NO-mediated S-nitrosylation and ERK regulation, which provide critical insights into the control of apoptosis and tumor development.