A small molecule inhibitor of Pim protein kinases blocks the growth of precursor T-cell lymphoblastic leukemia/lymphoma

Abstract The serine/threonine Pim kinases are up-regulated in specific hematologic neoplasms, and play an important role in key signal transduction pathways, including those regulated by MYC, MYCN, FLT3-ITD, BCR-ABL, HOXA9, and EWS fusions. We demonstrate that SMI-4a, a novel benzylidene-thiazolidine-2, 4-dione small molecule inhibitor of the Pim kinases, kills a wide range of both myeloid and lymphoid cell lines with precursor T-cell lymphoblastic leukemia/lymphoma (pre–T-LBL/T-ALL) being highly sensitive. Incubation of pre–T-LBL cells with SMI-4a induced G1 phase cell-cycle arrest secondary to a dose-dependent induction of p27Kip1, apoptosis through the mitochondrial pathway, and inhibition of the mammalian target of rapamycin C1 (mTORC1) pathway based on decreases in phospho-p70 S6K and phospho-4E-BP1, 2 substrates of this enzyme. In addition, treatment of these cells with SMI-4a was found to induce phosphorylation of extracellular signal-related kinase1/2 (ERK1/2), and the combination of SMI-4a and a mitogen-activated protein kinase kinase 1/2 (MEK1/2) inhibitor was highly synergistic in killing pre–T-LBL cells. In immunodeficient mice carrying subcutaneous pre–T-LBL tumors, treatment twice daily with SMI-4a caused a significant delay in the tumor growth without any change in the weight, blood counts, or chemistries. Our data suggest that inhibition of the Pim protein kinases may be developed as a therapeutic strategy for the treatment of pre–T-LBL.

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A new lead to NLRP3 inhibition

Journal of Experimental Medicine ◽

10.1084/jem.20171848 ◽

2017 ◽

Vol 214 (11) ◽

pp. 3147-3149 ◽

Cited By ~ 11

Author(s):

Mohamed Lamkanfi ◽

Vishva M. Dixit

Keyword(s):

Small Molecule ◽

Small Molecule Inhibitor ◽

Therapeutic Benefit ◽

Human Diseases ◽

Molecule Inhibitor ◽

Wide Range ◽

Potential Therapeutic Benefit

The discovery of a small molecule inhibitor that targets the inflammasome sensor NLRP3 offers a new path for the development of selective inflammasome blockers with potential therapeutic benefit in a wide range of human diseases (in this issue, see Jiang et al., https://doi.org/10.1084/jem.20171419).

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Safety of BXCL701, a small molecule inhibitor of dipeptidyl peptidases (DPP), with pembrolizumab, (pembro, anti-PD-1) monoclonal antibody, in men with metastatic castration-resistant prostate cancer (mCRPC).

Journal of Clinical Oncology ◽

10.1200/jco.2020.38.6_suppl.140 ◽

2020 ◽

Vol 38 (6_suppl) ◽

pp. 140-140

Author(s):

Rahul Raj Aggarwal ◽

Dan Costin ◽

Vincent J. O'Neill ◽

Cedric R Burg ◽

Diane I. Healey ◽

...

Keyword(s):

Prostate Cancer ◽

T Cell ◽

Small Molecule ◽

Dose Escalation ◽

Small Molecule Inhibitor ◽

Fixed Dose ◽

Phase 2 ◽

Final Dose ◽

Molecule Inhibitor ◽

Dipeptidyl Peptidases

140 Background: BXCL701 (talabostat previously PT100) is an oral small molecule inhibitor of dipeptidyl peptidases (DPP) specifically DPP4, DPP8 and DPP9, which trigger macrophage cell death via pyroptosis resulting in proinflammatory stimulation of the innate immunity pathway. BXCL701 also inhibits fibroblast activation protein (FAP) releasing the FAP-mediated block of T-cell migration into the tumor. Expression of PD-L1 correlates with amplification of DPP8 and DPP9. In syngeneic animal models, significant tumor responses were observed when BXCL701 was used with checkpoint inhibition. Methods: A phase 1b, multicenter study was undertaken. Eligible patients (pts) had progressing mCRPC (PCWG3), at least 1 line of systemic therapy and ≤ 2 lines of cytotoxic chemotherapy for mCRPC, no prior anti-PD-1/PD-L1 or other T-cell directed anti-cancer therapy, and an ECOG PS of ≤ 2. Pts received fixed dose pembro (200mg IV q21 days) with escalating doses of BXCL701 (0.4mg and 0.6mg PO QD days 1-14 of 21-day cycles) using a 3 X 3 design. The key endpoints were safety and identification of the recommended phase 2 dose (RP2D) for the combination. Composite response (RECIST, PSA, CTC) was also assessed. Results: 3 pts were treated at the initial dose level for at least 4 cycles. All pts remain on treatment. No DLT or SAEs were reported. Grade 3 treatment related adverse events (TRAE) were limited to thrombocytopenia with transfusion in 1 pt. The only TRAE reported in more than one pt was hypocalcemia (2 pts). Safety assessment of BXCL701+pembro is ongoing at the final dose escalation cohort. As DPP9 is amplified in approximately 17% of treatment associated small cell/neuroendocrine prostate cancer (tSCNC) compared to 5% or less in the broader prostate cancer population, the Phase 2 portion of this study will be limited to patients with evidence of t-SCNC or de novo SCNC, an aggressive phenotype with poor outcomes. Conclusions: BXCL701 0.4mg QD on days 1 to 14 of 21-day cycle plus pembrolizumab 200 mg IV on day 1 every 21 days is safe in pts with mCRPC. The final dose escalation supporting RP2D will be presented. Clinical trial information: NCT03910660.

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Evaluation of TW-37, a pan Bcl-2 Proteins Small-Molecule Inhibitor, Against Spectrum of Human B-Cell Lines and Patient-Derived Samples.

Blood ◽

10.1182/blood.v110.11.4521.4521 ◽

2007 ◽

Vol 110 (11) ◽

pp. 4521-4521

Author(s):

Ramzi M. Mohammad ◽

Yuan Sun ◽

Shaomeng Wang ◽

Amro Aboukameel ◽

Ayad M. Al-Katib

Keyword(s):

Tumor Growth ◽

B Cell ◽

Cell Lines ◽

Small Molecule ◽

Cell Lymphoma ◽

Lymphoblastic Leukemia ◽

B Cell Lymphoma ◽

Small Molecule Inhibitor ◽

Molecule Inhibitor ◽

Human B Cell

Abstract Non-Hodgkin’s lymphoma (NHL) tumors include a group of heterogeneous diseases with varying natural histories and responsiveness to therapy; nonetheless, overexpression of Bcl-2 protein is seen in more than 80% of NHL. Throughout the years our laboratory succeeded in establishing a panel of B-cell lines representing various maturational stages of NHL. In this study, we have utilized a structure-based strategy to design a new class of potent nonpeptidic small-molecule inhibitor (SMI) of Bcl-2 family. TW-37, a lead compound that was designed to target the BH3 binding groove of antiapopototic Bcl-2 proteins. It binds to Bcl-2, Bcl-XL and Mcl-1 with Ki values of 290 nM, 1110 nM and 260 nM, respectively. TW-37 showed significant antiproliferative effect against Pre-B-Acute Lymphoblastic Leukemia (WSU-pre-B-ALL), Diffuse Large Cell Lymphoma (WSU-DLCL2), Follicular Small Cleaved Cell Lymphoma (WSU-FSCCL), Waldenstrom’s Macroglobulinemia (WSU-WM) and primary cells obtained from lymphoma patients, despite variations in their anti- and pro-apoptotic Bcl-2 proteins (Bcl-2, Bcl-XL, Mcl-1, Bax, Bak, Bim, Bad, BUMA and Bok). The IC50 for TW-37 varied from 165 nM in the WSU-FSCCL to 300 nM in WSU-DLCL2 cells. Apoptosis was independent of proliferative status or pathological classification of B-cell tumor. TW-37 was able to block Bim-Bcl-XL and Bim-Mcl-1 eterodimerization and induces apoptosis via activation of caspases -9, -3, PARP and DNA fragmentation. Although cell lines and patient samples expressed multiple Bcl-2 family proteins at various levels, TW-37 induced apoptosis was only strongly associated with Bax:Mcl-1 ratio. TW-37 administered to tumor-bearing SCID mice led to significant tumor growth inhibition (T/C), tumor growth delay (T-C) and Log10kill, when used at its maximum tolerated dose (40 mg/kg x 3days) via tail vein. failed to induce changes in the Bcl-2 proteins levels suggests that assessment of baseline Bcl-2 family proteins can be used to prognosticate the response to drug. These findings indicate activity of TW-37 across the spectrum of human B-cell tumors and support the concept of targeting the Bcl-2 system as a therapeutic strategy in the treatment of B-cell lymphoma.

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