ProtectiveEffectofErythropoietinandItsCarbamylatedDerivative inExperimentalCisplatinPeripheralNeurotoxicity RobertoBianchi, 1 MichaelBrines, 3 GiuseppeLauria, 2 CostanzaSavino, 1 AlessandraGilardini, 4 GabriellaNicolini, 4 VirginiaRodriguez-Menendez, 4 NorbertoOggioni, 4 AnnalisaCanta, 4 PaolaPenza, 2 RaffaellaLombardi, 2 ClaudioMinoia, 5 AnnaRonchi, 5 AnthonyCerami, 3 PietroGhezzi, 1,3 andGuidoCavaletti 4 Abstract Purpose: Antineoplastic drugs, such as cisplatin (CDDP), are severely neurotoxic, causing disabling peripheral neuropathies with clinical signs known as chemotherapy-induced peripheral neurotoxicity. Cotreatment with neuroprotective agents and CDDP has been proposed for preventing or reversing the neuropathy. Erythropoietin given systemically has a wide range of neuroprotective actions in animal models of central and peripheral nervous system damage. However, the erythropoietic action is a potential cause of side effects if erythropoietin is used for neuroprotection. We have successfully identified derivatives of erythropoietin, including carbamylated erythropoietin, which do not raise the hematocrit but retain the neuroprotective action exerted by erythropoietin. ExperimentalDesign: We have developed previously an experimental chemotherapy-induced peripheral neurotoxicity that closely resembles CDDP neurotoxicity in humans. The present study compared the effects of erythropoietin and carbamylated erythropoietin (50 Ag/kg/d thrice weekly) on CDDP (2 mg/kg/d i.p. twice weekly for 4 weeks) neurotoxicity in vivo. Results: CDDPgiventoWistarratssignificantlyloweredtheirgrowthrate(P < 0.05),withslower sensory nerve conduction velocity (P < 0.001) and reducedintraepidermalnerve fibers density (P < 0.001versus controls). Coadministration of CDDP and erythropoietin or carbamylated erythropoietin partially but significantly prevented the sensory nerve conduction velocity reduction. Both molecules preservedintraepidermal nerve fiber density, thus confirming their neuroprotective effect at the pathologiclevel.The protective effects were not associated with anydifferenceinplatinumconcentrationindorsalrootganglia,sciaticnerve,orkidneyspecimens. Conclusions: These results widen the spectrum of possible use of erythropoietin and carbamylated erythropoietin as neuroprotectant drugs, strongly supporting their effectiveness. Chemotherapy-induced peripheral neurotoxicity (CIPN) is a major clinical problem because it is a dose-limiting side effect of important and effective antineoplastic drugs (1). The incidence, severity, and clinical symptoms and signs of CIPN depend on the drug given and its schedules. Severe neuropathy can occur in 3% to 7% of treated cases with single agents but can increase to 38% with combined regimens (2, 3). Moreover, even when CIPN is not dose-limiting, it may severely affect the quality of life of cancer patients and cause chronic discomfort. Therefore, effective prevention and/or treatment of CIPN would be a major advance for cancer patients. Cisplatin (CDDP) and the other platinum-derived drugs are among the most effective antineoplastic agents, but they are severely neurotoxic. The clinical features of CDDP neurotoxicity in humans are mainly ataxia, pain, and sensory impairment secondary to accumulation of CDDP in the dorsal root ganglia (DRG) and subsequent damage, resulting in secondary nerve fiber axonopathy. We have developed an experimental model of peripheral neurotoxicity induced by CDDP (4–9) that closely resembles CDDP neurotoxicity in humans. It involves the reversible primary involvement of DRG neurons, with secondary sensory axonal neuropathy and sparing of the motoneurons. This model has already been used to investigate the mechanisms of neurotoxic action of CDDP (4, 5, 7, 9) and to test the effect of putative neuroprotective agents (6, 8–13). Among these agents, cotreatment with neurotrophic agents has been proposed as a means of preventing or reversing CIPN (14). Among the several substances with throphic action on central neurons and peripheral nerves, erythropoietin has a Cancer Therapy: Preclinical Authors’Affiliations: 1 ‘‘Mario Negri’’Institute for Pharmacological Research; 2 ‘‘Besta’’National Neurological Institute, Milan, Italy; 3 Kenneth S.Warren Institute, Kitchawan, NewYork; 4 UniversityofMilan‘‘Bicocca,’’Monza,Italy;and 5 ‘‘Maugeri’’ Foundation, Pavia, Italy Received10/5/05;revised1/16/06;accepted1/26/06. Grantsupport: FondazioneBancaDelMontediLombardia(G.Cavaletti). Thecostsofpublicationofthisarticleweredefrayedinpartbythepaymentofpage charges.Thisarticlemustthereforebeherebymarked advertisement inaccordance with18U.S.C.Section1734solelytoindicatethisfact. Requests for reprints: Roberto Bianchi, Molecular Biochemistry and Pharmacology,‘‘Mario Negri’’ Institute for Pharmacological Research,Via Eritrea, 62, Milan 20157, Italy. Phone: 39-239014484; Fax: 39-02-3546277; E-mail: robbia@marionegri.it. F 2006AmericanAssociationforCancerResearch. doi:10.1158/1078-0432.CCR-05-2177 www.aacrjournals.org ClinCancerRes2006;12(8)April15,2006 2607