Cell experiment:

Hematopoietic cancer cells are incubated with different concentrations of Motixafortide (BKT140) or AMD3100 for 24 hours. Motixafortide (BKT140) is treated with 1M hydrochloric acid (HCL) to achieve a pH of 2.7 to 3 at room temperature for 30 minutes and the pH is adjusted to 7 using concentrated NaOH. Proteinase K is added to Motixafortide (BKT140) at a final concentration of 100 mg/mL, incubated at 37℃ for 1 hour, and inactivated by heat treatment (65℃ for 30 minutes). After incubation, cells are stained with propidium iodide and the percent of viable PI-negative cells in culture is determined[2].

Animal experiment:

Mice: Severe combined immune-deficient (SCID)/beige mice (C.B-17/IcrHsd-SCID-bg) are used in the study. NB4 cells resuspended in PBS are injected subcutaneously into the flanks of the mice (200 mL per mouse containing 5×106 cells). Tumor growth is monitored daily, and mice are randomized to drug-treated or control PBS-treated groups (10 mice per group) when the tumor size (width×length) reaches 0.04 cm2. BKT140 is administered subcutaneously at a dose of 200 mg per mouse each day for 5 days[2].

BKT140, also known as BL-8040 and TF 14016, is an orally bioavailable inhibitor of CXC Chemokine Receptor 4 (CXCR4) with potential antineoplastic activity [1].

The G protein-coupled receptor CXCR4 plays an important role in chemotaxis and angiogenesis and is upregulated in several tumor cell types. CXCR4 has been involved in promoting tumor progression. CXCR4 expression is a prognostic marker in various types of cancer, such as acute myelogenous leukemia or breast carcinoma. CXCR4 acts as an important molecule involved in the spread and progression of a variety of different tumors [2].

BKT140 reduced the colony-forming capacity of non-small cell lung cancer (NSCLC) cells. Subcutaneous administration of BKT140 significantly delayed the development of H460 xenografts and showed a similar trend for A549 xenografts [1]. Pre-clinical studies in animal models with BKT140 showed a robust mobilization of white blood cells (WBC) and hematopoietic stem cells (HSC). BKT140 showed a direct anti-tumor effect against human-derived multiple myeloma (MM), lymphoma and primary leukemia cells and cell lines in vitro and in vivo, causing significant apoptosis [2]. BKT140 was well tolerated and rapidly absorbed in patients with multiple myeloma. BKT140 administration significantly increased the number of peripheral blood neutrophils, monocytes, lymphocytes, and CD34+ cells in a dose-dependent manner [3].

References:
[1] Fahham D, Weiss I D, Abraham M, et al.  In vitro and in vivo therapeutic efficacy of CXCR4 antagonist BKT140 against human non–small cell lung cancer[J]. The Journal of thoracic and cardiovascular surgery, 2012, 144(5): 1167-1175. e1.
[2] Burger J A, Kipps T J.  CXCR4: a key receptor in the crosstalk between tumor cells and their microenvironment[J]. Blood, 2006, 107(5): 1761-1767.
[3] Nagler A, Shimoni A, Avivi I, et al.  BKT140 is a novel CXCR4 antagonist with stem cell mobilization and antimyeloma effects: an open-label first human trial in patients with multiple myeloma undergoing stem cell mobilization for autologous transplantation[J]. Blood, 2010, 116(21): 2260-2260.