Development of Dl1.72, a Novel Anti-DLL1 Antibody with Anti-Tumor Efficacy against Estrogen Receptor-Positive Breast Cancer

Novel insights into Notch signaling in tumor immunity: potential targets for cancer immunotherapy

Notch signaling pathway is a highly conserved system of cell-to-cell communication that participates in various biological processes, such as stem cell maintenance, cell fate decision, cell proliferation and death during homeostasis and development. Dysregulation of Notch signaling has been associated with many aspects of cancer biology, such as maintenance of cancer stem-like cells (CSCs), cancer cell metabolism, angiogenesis and tumor immunity. Particularly, Notch signaling can regulate antitumor or pro-tumor immune cells within the tumor microenvironment (TME). Currently, Notch signaling has drawn significant attention in the therapeutic development of cancer treatment. In this review, we focus on the role of Notch signaling pathway in remodeling tumor immune microenvironment. We describe the impact of Notch signaling on the efficacy of cancer immunotherapies. Furthermore, we summarize the results of relevant preclinical and clinical trials of Notch-targeted therapeutics and discuss the challenges in their clinical application in cancer therapy. An improved understanding of the involvement of Notch signaling in tumor immunity will open the door to new options in cancer immunotherapy treatment.

NOTCH Signaling Pathway: Occurrence, Mechanism, and NOTCH-Directed Therapy for the Management of Cancer

It is now well understood that many signaling pathways are vital in carrying out and controlling essential pro-survival and pro-growth cellular functions. The NOTCH signaling pathway, a highly conserved evolutionary signaling pathway, has been thoroughly studied since the discovery of NOTCH phenotypes about 100 years ago in Drosophila melanogaster. Abnormal NOTCH signaling has been linked to the pathophysiology of several diseases, notably cancer. In tumorigenesis, NOTCH plays the role of a "double-edged sword," that is, it may act as an oncogene or as a tumor suppressor gene depending on the nature of the context. However, its involvement in several cancers and inhibition of the same provides targeted therapy for the management of cancer. The use of gamma (γ)-secretase inhibitors and monoclonal antibodies for cancer treatment involved NOTCH receptors inhibition, leading to the possibility of a targeted approach for cancer treatment. Likewise, several natural compounds, including curcumin, resveratrol, diallyl sulfide, and genistein, also play a dynamic role in the management of cancer by inhibition of NOTCH receptors. This review outlines the functions and structure of NOTCH receptors and their associated ligands with the mechanism of the signaling pathway. In addition, it also emphasizes the role of NOTCH-targeted nanomedicine in various cancer treatment strategies.

Novel scFv against Notch Ligand JAG1 Suitable for Development of Cell Therapies toward JAG1-Positive Tumors

The Notch signaling ligand JAG1 is overexpressed in various aggressive tumors and is associated with poor clinical prognosis. Hence, therapies targeting oncogenic JAG1 hold great potential for the treatment of certain tumors. Here, we report the identification of specific anti-JAG1 single-chain variable fragments (scFvs), one of them endowing chimeric antigen receptor (CAR) T cells with cytotoxicity against JAG1-positive cells. Anti-JAG1 scFvs were identified from human phage display libraries, reformatted into full-length monoclonal antibodies (Abs), and produced in mammalian cells. The characterization of these Abs identified two specific anti-JAG1 Abs (J1.B5 and J1.F1) with nanomolar affinities. Cloning the respective scFv sequences in our second- and third-generation CAR backbones resulted in six anti-JAG1 CAR constructs, which were screened for JAG1-mediated T-cell activation in Jurkat T cells in coculture assays with JAG1-positive cell lines. Studies in primary T cells demonstrated that one CAR harboring the J1.B5 scFv significantly induced effective T-cell activation in the presence of JAG1-positive, but not in JAG1-knockout, cancer cells, and enabled specific killing of JAG1-positive cells. Thus, this new anti-JAG1 scFv represents a promising candidate for the development of cell therapies against JAG1-positive tumors.

Identification of the molecular subtype and prognostic characteristics of pancreatic cancer based on CD8 + T cell-related genes

CD8 + T lymphocytes are immune cells that play a crucial anti-tumor role in the human body, and prognostic value of CD8 + T cell-related regulatory genes in PAAD remains elusive. Data on 179 expression profiles across 13 immune cell datasets were downloaded from the GEO database, and the expression profiles of CD8 + T cell-related genes were obtained using WGCNA. Molecular subtypes based on CD8 + T cell-related genes were constructed using the ConsensusClusterPlus algorithm. Lasso regression analysis was performed to build a 10-gene signature. GSVA was performed to explore the pathways related to these ten genes. The IMvigor210 cohort was used to explore the predictive efficacy of the signature in terms of immunotherapy response. Four hundred and forty-six CD8 + T cell-related genes were obtained. One hundred and nine genes in TCGA and GEO datasets were closely related to the prognosis of patients and were included in the next study. PAAD samples were divided into two subtypes (IC1 and IC2) according to consensus cluster analysis. These two immune subtypes were significantly different in terms of immune checkpoint genes, immune function, and drug treatment response. Additionally, the 10-gene signature constructed based on CD8 + T cell-related genes showed a stable prognostic performance in TCGA and GEO cohorts. Moreover, it served as an independent prognostic factor for patients with PAAD. Furthermore, the 10-gene signature could effectively predict the response to immunotherapy. The immunophenotyping-derived prognostic model based on CD8 T cell-related genes provides a basis for the clinical treatment of pancreatic cancer.

Interaction between BEND5 and RBPJ suppresses breast cancer growth and metastasis via inhibiting Notch signaling

High frequent metastasis is the major cause of breast cancer (BC) mortality among women. However, the molecular mechanisms underlying BC metastasis remain largely unknown. Here, we identified six hub BC metastasis driver genes (BEND5, HSD11B1, NEDD9, SAA2, SH2D2A and TNFSF4) through bioinformatics analysis, among which BEND5 is the most significant gene. Low BEND5 expression predicted advanced stage and shorter overall survival in BC patients. Functional experiments showed that BEND5 could suppress BC growth and metastasis in vitro and in vivo. Mechanistically, BEND5 inhibits Notch signaling via directly interacting with transcription factor RBPJ/CSL. BEN domain of BEND5 interacts with the N-terminal domain (NTD) domain of RBPJ, thus preventing mastermind like transcriptional coactivator (MAML) from forming a transcription activation complex with RBPJ. Our study provides a novel insight into regulatory mechanisms underlying Notch signaling and suggests that BEND5 may become a promising target for BC therapy.