mitonafide and Neoplasms

Eleven patients with solid tumors for whom effective therapy was not available entered a phase I study of mitonafide given as a short intravenous (i.v.) infusion daily for 3 consecutive days. The initial dose level was selected according to the experience from another phase I study using a 5-day administration schedule. Six patients entered the first dose level (180 mg/m2/day x 3 days) and 4 of them had grade 3-4 leukopenia. This level was considered to be the maximum tolerated dose (MTD) and no further dose escalations were attempted. The following 5 patients received a dose approximately 10% inferior to the previous one (160 mg/m2/day x 3 days). Three of them had grade 3-4 neutropenia. Three partial responses were observed in total. After inclusion of 11 patients, an unexpected toxicity, central nervous system (CNS) toxicity, consisting of severe loss of memory, temporospatial disorientation and high integrative function impairment was observed in 5 patients (46%). A median patients' follow-up of 3 months after treatment discontinuation showed that these alterations were progressive and not reversible. This disabling toxicity prompted us to an early study interruption. In conclusion, mitonafide, when administered as a short 3-day i.v. infusion, can induce severe and irreversible CNS toxicity. Nevertheless, since antitumor activity has been observed, further development of the drug is recommended with different schedules of administration that have shown not to produce neurotoxicity, i.e., 5-day continuous infusion.

Topics: Adult; Aged; Antineoplastic Agents; Central Nervous System Diseases; Drug Administration Schedule; Female; Humans; Imides; Isoquinolines; Male; Middle Aged; Naphthalimides; Neoplasms

Mitonafide was the first synthetized compound of a new series of 3-nitronaphthalimides with intercalative properties. A phase I study with a conventional escalation scheme was developed. The schedule of drug administration was a daily x 5 days by short (1 h) intravenous (i.v.) infusion, every 21 days. Thirty evaluable patients were treated at doses from 15.4 mg/m2/d x 5 days to 138.6 mg/m2/d x 5 days. The study was interrupted due to appearance of central nervous system toxicity in 5 patients treated at doses above 118 mg/m2 x 5 days. This toxicity consisted firstly of loss of memory in all patients. It was irreversible and progressed in 3 patients to disorientation and confusion, leading to dementia in one of them. This was considered to be dose-limiting toxicity, and since it appeared to be related to the administration schedule, no further studies with short i.v. infusions of mitonafide are recommended. A phase I study utilizing a more desirable administration schedule over longer periods of time is ongoing in other centers.

Topics: Adult; Aged; Antineoplastic Agents; Dose-Response Relationship, Drug; Female; Humans; Imides; Infusions, Intravenous; Isoquinolines; Male; Memory Disorders; Middle Aged; Naphthalimides; Neoplasms

Four series of new 3-nitro naphthalimides derivatives, 4(4a‒4f), 5(5a‒5i), 6(6a‒6e) and 7 (7a‒7j), were designed and synthesized as antitumor agents. Methyl thiazolyl tetrazolium (MTT) screening assay results revealed that some compounds displayed effective in vitro antiproliferative activity on SMMC-7721, T24, SKOV-3, A549 and MGC-803 cancer cell lines in comparison with 5-fluorouracil (5-FU), mitonafide and amonafide. Nude mouse xenotransplantation model assay results indicated that compounds 6b and 7b exhibited good in vivo antiproliferative activity in MGC-803 xenografts in comparison with amonafide and cisplatin, suggesting that compounds 6b and 7b could be good candidates for antitumor agents. Gel electrophoresis assay indicated that DNA and Topo I were the potential targets of compounds 6b and 7b, and comet assay confirmed that compounds 6b and 7b could induce DNA damage, while the further study showed that the 6b- and 7b-induced DNA damage was accompanied by the upregulation of p-ATM, P-Chk2, Cdc25A and p-H2AX. Cell cycle arrest studies demonstrated that compounds 6b and 7b arrested the cell cycle at the S phase, accompanied by the upregulation of the expression levels of the antioncogene p21 and the down-regulation of the expression levels of cyclin E. Apoptosis assays indicated that compounds 6b and 7b caused the apoptosis of tumor cells along with the upregulation of the expression of Bax, caspase-3, caspase-9 and PARP and the downregulation of Bcl-2. These mechanistic studies suggested that compounds 6b and 7b exerted their antitumor activity by targeting to DNA, thereby inducing DNA damage and Topo I inhibition, and consequently causing S stage arrest and the induction of apoptosis.

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Nucleus; Cell Proliferation; DNA Damage; Drug Design; Humans; Mice, Nude; Naphthalimides; Neoplasms

Novel tertiary amine N-oxides of naphthalimides were designed and synthesized as potential anticancer agents against hypoxic solid tumors. Although their ctDNA-binding affinities and cytotoxic activities against usual tumor cell lines were lower than those of corresponding amines, the N-oxides A1 and A4 showed hypoxia preference activities against A375 cells in vitro and might be used as interesting candidates of prodrug leads in hypoxic tumor cells.

Topics: Antineoplastic Agents; Cell Hypoxia; Cell Line, Tumor; Drug Screening Assays, Antitumor; Humans; Naphthalimides; Neoplasms; Oxides; Prodrugs; Structure-Activity Relationship