Abstract
Background: Patients with advanced-stage ovarian cancer face a poor prognosis because of recurrent peritoneal cavity metastases following surgery and chemotherapy. Alpha-emitters may enable the efficient treatment of such disseminated diseases because of their short range and highly energetic radiation. Radium-224 is a candidate α-emitter due to its convenient 3.6-day half-life, with more than 90% of the decay energy originating from α-particles. However, its inherent skeletal accumulation must be overcome to facilitate intraperitoneal delivery of the radiation dose. Therefore, 224Ra-labeled CaCO3 microparticles have been developed.
Objective: The antitumor effect of CaCO3 microparticles as a carrier for 224Ra was investigated, with an emphasis on the ratio of activity to mass dose of CaCO3, that is, specific activity.
Methods: Nude athymic mice were inoculated intraperitoneally with human ovarian cancer cells (ES-2) and treated with a single intraperitoneal injection of 224Ra-labeled CaCO3 microparticles with varying combinations of mass and activity dose, or cationic 224Ra in solution. Survival and ascites volume at sacrifice were evaluated.
Results: Significant therapeutic effect was achieved for all tested specific activities ranging from 0.4 to 4.6 kBq/mg. Although treatment with a mean activity dose of 1305 kBq/kg of cationic 224Ra prolonged the survival compared with the control, equivalent median survival could be achieved with 224Ra-labeled microparticles with a mean dose of only 420 kBq/kg. The best outcome was achieved with the highest specific activities (2.6 and 4.6 kBq/mg).
Conclusion: Radium-224-labeled CaCO3 microparticles present a promising therapy against cancer dissemination in body cavities.
Keywords: Alpha therapy, calcium carbonate, microparticles, radium-224, 224Ra, peritoneal carcinomatosis, intraperitoneal, ovarian cancer.
Graphical Abstract
[http://dx.doi.org/10.1016/S0140-6736(17)33326-3] [PMID: 29395269]
[http://dx.doi.org/10.1155/2010/497429] [PMID: 20066162]
[http://dx.doi.org/10.1093/annonc/mdx011] [PMID: 28327917]
[http://dx.doi.org/10.1016/j.suronc.2017.01.001] [PMID: 28317584]
[http://dx.doi.org/10.1097/00006254-197909000-00028] [PMID: 386194]
[http://dx.doi.org/10.1016/0360-3016(89)90337-4] [PMID: 2921145]
[PMID: 8377986]
[http://dx.doi.org/10.1006/gyno.1996.4577] [PMID: 9103398]
[PMID: 12231520]
[http://dx.doi.org/10.1200/JCO.2005.02.5973] [PMID: 16446329]
[http://dx.doi.org/10.1002/1097-0142(19920201)69:3<741::AID-CNCR2820690322>3.0.CO;2-G] [PMID: 1730124]
[http://dx.doi.org/10.1016/0090-8258(85)90266-5] [PMID: 4040049]
[http://dx.doi.org/10.1016/0090-8258(92)90141-5] [PMID: 1473751]
[http://dx.doi.org/10.1016/0360-3016(84)90052-X] [PMID: 6706730]
[http://dx.doi.org/10.1007/s00259-010-1639-2] [PMID: 21072513]
[PMID: 27906723]
[http://dx.doi.org/10.2967/jnumed.109.062604] [PMID: 19525452]
[http://dx.doi.org/10.2967/jnumed.118.220384] [PMID: 30683761]
[http://dx.doi.org/10.1016/j.ijrobp.2014.12.061] [PMID: 25832684]
[http://dx.doi.org/10.1016/S0969-8043(01)00282-2] [PMID: 11993940]
[http://dx.doi.org/10.1021/ic990135+] [PMID: 21494420]
[http://dx.doi.org/10.1039/C9CC02587A] [PMID: 31197298]
[http://dx.doi.org/10.1016/j.nucmedbio.2015.03.007] [PMID: 25900730]
[http://dx.doi.org/10.1016/j.nucmedbio.2016.11.005] [PMID: 28043005]
[http://dx.doi.org/10.1007/s11051-013-2082-7] [PMID: 24307862]
[http://dx.doi.org/10.1039/C9QI00208A]
[http://dx.doi.org/10.1007/s10967-014-3615-y]
[http://dx.doi.org/10.1007/s10967-016-5007-y]
[http://dx.doi.org/10.1016/j.nucmedbio.2003.11.004] [PMID: 15093814]
[PMID: 16886603]
[http://dx.doi.org/10.1002/ijc.23268] [PMID: 18059026]
[http://dx.doi.org/10.1016/j.ijrobp.2009.02.063] [PMID: 19480976]
[PMID: 23225432]
[http://dx.doi.org/10.1088/0031-9155/52/16/021] [PMID: 17671351]
[http://dx.doi.org/10.5114/jcb.2019.88138] [PMID: 31749854]
[PMID: 31759075]
[http://dx.doi.org/10.1002/jlcr.3610] [PMID: 29380410]
[http://dx.doi.org/10.1016/j.tranon.2017.12.011] [PMID: 29413758]
[http://dx.doi.org/10.1016/j.ymthe.2004.08.013] [PMID: 15564135]
[http://dx.doi.org/10.21873/anticanres.13800] [PMID: 31704820]
[http://dx.doi.org/10.1006/gyno.1995.1093] [PMID: 7705707]
[http://dx.doi.org/10.1089/cbr.2009.0618] [PMID: 19694586]