Nuclear Medicine Application of Pentixafor/Pentixather Targeting CXCR4 for Imaging and Therapy in Related Disease



C-X-C-motif chemokine receptor 4 (CXCR4) is a novel predictive biomarker for metastasis and poor prognosis in individuals with malignancies. CXCL12 is the only cognate ligand of CXCR4. CXCL12/CXCR4 signaling pathways are involved in the cross-talk among cancer cells, T cells, stromal cells, and their microenvironments, including the regulation and direction of T cell migration (chemotaxis), proliferation, and differentiation of immature progenitor stem cells. As CXCR4 overexpression is related to tumor prognosis, it is essential to quantitatively evaluate CXCR4 expression levels in vivo.
68Ga-Pentixafor, as a radiolabeled tracer, shows high specificity and affinity for CXCR4 in tumors. Thus, CXCR4-directed imaging with 68Ga-Pentixafor has been investigated to evaluate CXCR4 expression in patients non-invasively. In recent years, many small cohorts, including those of individuals with hematologic malignancies, solid tumors, and cardiovascular and infectious diseases, have been reported. So far, 68Ga-Pentixafor has been used successfully in individuals with hematologic malignancies. In addition, Lutetium-177 (177Lu) or Yttrium-90 (90Y)-labeled Pentixather (an analog of Pentixafor) suggested high potential applicability in tumor endoradiotherapy (ERT) with CXCR4 overexpression. Patients with advanced-stage multiple myeloma, refractory acute leukemia, and diffuse large B-cell lymphoma received a certain amount of 177Lu-Pentixather or 90Y-Pentixather. This review aimed to overview the current CXCR4-directed positron emission computed tomography (PET) molecular imaging based on Pentixafor in several diseases and ERT.
