In vivo knockdown of CXCR4 using jetPEI/CXCR4 shRNA nanoparticles inhibits the pulmonary metastatic potential of B16-F10 melanoma cells

Abstract

Metastasis is a key factor that limits survival in the majority of patients with cancer. Thus, numerous efforts have been made to elucidate the molecular mechanisms involved in this phenomenon. B16‑F10 melanoma cells have been demonstrated to be highly metastatic to the lungs in mice. The aim of the current study was to investigate the role of CXC motif chemokine receptor 4 (CXCR4) in the metastatic potential of B16‑F10 melanoma cells in mice. In vitro transfection of B16‑F10 tumor cells with CXCR4 short hairpin RNA (shRNA) expressing plasmids (CXCR4 shRNA) significantly reduced the expression levels of CXCR4 mRNA (80%) and protein (68%), compared with the control. In addition, these results demonstrated that pulmonary metastasis was significantly inhibited (85%) in mice inoculated with CXCR4 shRNA‑transfected B16‑F10 melanoma cells. The polycation‑based nanoparticle (jetPEI) was used to investigate the effect of CXCR4 knockdown in vivo on the metastatic potential of B16‑F10 melanoma cells. The number of pulmonary metastatic nodules was significantly reduced (50%) in animals that received a retro‑orbital injection of jetPEI‑CXCR4‑1 shRNA. The current study demonstrated that CXCR4 serves a role in the metastatic potential of B16‑F10 melanoma cells. Currently there is a great interest in the development of antagonists for the therapeutic targeting of CXCR4 expression. Taking the results of the current study and the fact that CXCR4 is highly conserved between humans and mice into account, this experimental model of metastasis with B16‑F10 melanoma cells may aid in the discovery of CXCR4 antagonists with clinical implications.

Overexpression of amplified in breast cancer 1 (AIB1) gene promotes lung adenocarcinoma aggressiveness in vitro and in vivo by upregulating C‐X‐C motif chemokine receptor 4

“…We synthesized the sequences of AIB1 to construct lentiviral shRNA1 (5′-GGTCTTACCTGCAGTGGTGAA-3′) and shRNA2 (5′-AGACTCCTTAGGACC GCTT-3′), which have been previously found to efficiently knock down endogenous AIB1 expression in human cancer cells [ 14 ]. The shRNA sequence for CXCR4 is 5′-ACCGCGATCAGTGTGAGTATATAAAGTTCTCTTATATACTCACACTGATCGCTTTTTC-3′, which was also previously validated [ 24 ]. Virus packaging was performed by the transient transfection of 293FT cells with a transfer plasmid and three packaging plasmids: pMDLg/pRRE, pRSV-REV, and pCMV-VSVG, which were kindly provided by Professor Peng Xiang (Center for Stem Cell Biology and Tissue Engineering, Sun Yat-sen University).…”

Chemokine Pathways in Cutaneous Melanoma: Their Modulation by Cancer and Exploitation by the Clinician

“…For example, the CXCR4–CXCL12 axis has been associated with pulmonary, as well as liver and bone marrow, metastases [ 49 , 55 ]. The expression of CXCR4 by melanoma cells in patient samples has been correlated with the likelihood of pulmonary metastasis [ 50 , 51 ] and increased pulmonary metastasis has been seen in mice inoculated with melanoma cells overexpressing CXCR4 [ 52 , 53 , 54 ], with CXCR4 inhibition reversing this effect [ 56 ]. The binding of chemokines to their receptors induces inside-out signalling, leading to affinity changes in integrins, which is a prerequisite for cell attachment and subsequent transendothelial migration [ 106 ].…”

Spontaneous and Induced Animal Models for Cancer Research

“…Numerous studies opt for this type of implantation, not only for leukemia, but also for developing metastatic models for various cancers. A melanoma cancer lung metastatic profile was achieved via retro-orbital vein injection and followed up with in vivo live imaging [157]. This lung metastatic profile can also be obtained through retro-orbital sinus inoculation of melanoma cells [158].…”