Background: Our previous work demonstrated upregulated CD47 in Oral Squamous Cell Carcinoma (OSCC).
Objective: In the present study, we aimed to investigate the effects of CD47 on tumor cell development and phagocytosis in OSCC and elucidate the underlying mechanisms.
Methods: The proliferation, apoptosis, migration, and invasion of oral cancer cells were analyzed after knocking down the expression of CD47. The effects of CD47 on tumor development were also evaluated using a murine model of OSCC. The involvement of CD47 in the phagocytosis of oral cancer cells was identified.
Results: Cell proliferation was suppressed by knocking down the expression of CD47 in human OSCC cell line Cal-27 cells but there was no change in the apoptosis rate. Moreover, impaired expression of CD47 inhibited the migration and invasion of Cal-27 cells. Furthermore, we found that nude mice injected with CD47 knockeddown Cal-27 cells displayed decreased tumor volumes at week 9 compared to xenograft transplantations of blank Cal-27 cells. In addition, in vitro phagocytosis of Cal-27 cells by macrophages was significantly enhanced after the knockdown of CD47, which positively correlated with compromised STAT3/JAK2 signaling.
Conclusion: In summary, the knockdown of CD47 downregulated the development of OSCC and increased the phagocytosis of Cal-27 cells, indicating that CD47 might be a promising therapeutic target.
[http://dx.doi.org/10.1111/j.1476-5381.2012.02099.x] [PMID: 22774848]
[http://dx.doi.org/10.1146/annurev-immunol-032713-120142] [PMID: 24215318]
[http://dx.doi.org/10.1016/j.coi.2015.06.013] [PMID: 26172292]
[http://dx.doi.org/10.1073/pnas.1121623109] [PMID: 22451913]
[http://dx.doi.org/10.1002/cam4.478] [PMID: 26077800]
[http://dx.doi.org/10.1126/scitranslmed.3009457] [PMID: 25355698]
[http://dx.doi.org/10.1016/j.oraloncology.2015.11.022] [PMID: 26733183]
[http://dx.doi.org/10.1371/journal.pone.0109114] [PMID: 25296162]
[http://dx.doi.org/10.1073/pnas.0906549106] [PMID: 19666525]
[http://dx.doi.org/10.1002/glia.21102] [PMID: 21125662]
[http://dx.doi.org/10.1074/jbc.M114.550558] [PMID: 24550402]
[http://dx.doi.org/10.4049/jimmunol.1401719] [PMID: 26085683]
[http://dx.doi.org/10.3892/or.17.5.1189] [PMID: 17390064]
[http://dx.doi.org/10.1111/liv.12963] [PMID: 26351778]
[http://dx.doi.org/10.1016/j.canlet.2015.02.036] [PMID: 25721088]
[http://dx.doi.org/10.1038/nm976] [PMID: 14702634]
[http://dx.doi.org/10.1016/j.oraloncology.2015.03.004] [PMID: 25817923]
[http://dx.doi.org/10.3960/jslrt.51.93] [PMID: 22104307]