TLR Signaling Is Activated in Lymph Node-Resident CLL Cells and Is Only Partially Inhibited by Ibrutinib.

Chronic lymphocytic leukemia (CLL) is a malignancy of mature B cells driven by B-cell receptor (BCR) signaling and activated primarily in the lymph node. The Bruton's tyrosine kinase (BTK) inhibitor ibrutinib effectively inhibits BCR-dependent proliferation and survival signals and has emerged as a breakthrough therapy for CLL. However, complete remissions are uncommon and are achieved only after years of continuous therapy.

Potent and selective antitumor activity of a T cell-engaging bispecific antibody targeting a membrane-proximal epitope of ROR1.

T cell-engaging bispecific antibodies (biAbs) present a promising strategy for cancer immunotherapy, and numerous bispecific formats have been developed for retargeting cytolytic T cells toward tumor cells. To explore the therapeutic utility of T cell-engaging biAbs targeting the receptor tyrosine kinase ROR1, which is expressed by tumor cells of various hematologic and solid malignancies, we used a bispecific ROR1 × CD3 scFv-Fc format based on a heterodimeric and aglycosylated Fc domain designed for extended circulatory and diminished systemic T cell activation. A diverse panel of ROR1-targeting scFv derived from immune and naïve rabbit antibody repertoires was compared in this bispecific format for target-dependent T cell recruitment and activation.

A CD19/CD3 bispecific antibody for effective immunotherapy of chronic lymphocytic leukemia in the ibrutinib era.

The Bruton tyrosine kinase inhibitor ibrutinib induces high rates of clinical response in chronic lymphocytic leukemia (CLL). However, there remains a need for adjunct treatments to deepen response and to overcome drug resistance. Blinatumomab, a CD19/CD3 bispecific antibody (bsAb) designed in the BiTE (bispecific T-cell engager) format, is approved by the US Food and Drug Administration for the treatment of relapsed or refractory B-cell precursor acute lymphoblastic leukemia.

MALT1 Inhibition Is Efficacious in Both Naïve and Ibrutinib-Resistant Chronic Lymphocytic Leukemia.

The clinical efficacy displayed by ibrutinib in chronic lymphocytic leukemia (CLL) has been challenged by the frequent emergence of resistant clones. The ibrutinib target, Bruton's tyrosine kinase (BTK), is essential for B-cell receptor signaling, and most resistant cases carry mutations in or , a downstream effector target of BTK. Recent findings show that MI-2, a small molecule inhibitor of the para-caspase MALT1, is effective in preclinical models of another type of BCR pathway-dependent lymphoma.

Combined BTK and PI3Kδ Inhibition with Acalabrutinib and ACP-319 Improves Survival and Tumor Control in CLL Mouse Model.

Targeting the B-cell receptor (BCR) pathway with inhibitors of Bruton tyrosine kinase (BTK) and PI3Kδ is highly effective for the treatment of chronic lymphocytic leukemia (CLL). However, deep remissions are uncommon, and drug resistance with single-agent therapy can occur. studies support the effectiveness of combing PI3Kδ and BTK inhibitors.

Tracking and Functional Characterization of Epithelial-Mesenchymal Transition and Mesenchymal Tumor Cells during Prostate Cancer Metastasis.

The epithelial-mesenchymal transition (EMT) has been postulated as a mechanism by which cancer cells acquire the invasive and stem-like traits necessary for distant metastasis. However, direct in vivo evidence for the role of EMT in the formation of cancer stem-like cells (CSC) and the metastatic cascade remains lacking. Here we report the first isolation and characterization of mesenchymal-like and EMT tumor cells, which harbor both epithelial and mesenchymal characteristics, in an autochthonous murine model of prostate cancer.