SUMMARY
Background: The progressive growth of tumors and their ability to metastasize are dependent on an adequate
tumor blood supply. Chemokine (C-X-C motif) ligand 1 (CXCL1), a well-known chemokine, has been identified
as a potential therapeutic target for bladder cancers (BCa) as well as urinary biomarker for BCa detection.
Chemokines are known to be critical mediators of the inflammatory response by regulating recruitment of
immune cells from both the innate and adaptive immune systems to diseased tissues. Also, chemokines have
been known to regulate multiple processes during tumor progression including primary tumor growth, tumor
angiogenesis and development of metastatic disease. Previously, we found that CXCL1 is overexpressed in
BCa and CXCL1 expression is associated with a worse disease-specific survival. We also reported that CXCL1
is expressed and secreted from human endothelial cells and interference of CXCL1 function using a
neutralizing antibody resulted in a reduction in endothelial cell migration and cellular proliferation. We
previously developed mouse anti-human CXCL1 monoclonal antibody (HL2401) and demonstrated that
inhibition of CXCL1 by HL2401 results in the diminution of bladder and prostate xenograft tumoral growth
through the inhibition of angiogenesis and proliferation along with an induction of apoptosis. Recently, we
developed a first-in-class humanized neutralizing monoclonal antibody towards CXCL1 (NTC-001), that if
found to be effective and safe in animals, could readily move into phase 1 clinical trials. Pilot studies
demonstrated that NTC-001 inhibited capillary tube formation and sprouting in HUVEC and cell proliferation in
BCa cell lines with IC50 value of 60-165 µg/ml. Hypothesis: Neutralization of CXCL1 by humanized
monoclonal antibody can be a potent strategy for BCa therapy. Specific Aims: 1) To assess whether our
humanized anti-CXCL1 antibody, NTC-001, exhibit inhibitory effects on angiogenesis and tumor growth in vivo;
2) To examine the effect of NTC-001 on tumor growth in a humanized BCa patient-derived xenograft (PDX)
model. Significance: The results obtained from this project will provide a new drug into the clinic for BCa
therapy and beyond. Methodology: With animal models including Matrigel plug assay and human BCa cell
line derived xenografts, we will assess the effect of humanized antibody on angiogenesis and tumor growth.
Using BCa patient-derived xenograft model in humanized immune system mice, we will examine 1) the efficacy
of NTC-001 on tumor growth and survival, 2) potential effects, specifically neutropenia, and 3) the effects on
the tumor microenvironment. Expected Results: Based on our previous works, we expect that anti-human
CXCL1 humanized antibody is effective on bladder tumorigenesis. How results will affect other research
areas: Since CXCL1 is highly expressed in most cancers, the findings will have important implications on
developing new therapies against other cancers.