(11aS)-7-Methoxy-8-hydroxy-2,3,5,11aβ-tetrahydro-1H-pyrrolo[2,1-c][1,4]benzodiazepine-5-one

Antibiotic DC 81 (DC 81), an antitumor antibiotic produced by Streptomyces species, is a PBD (pyrrolo[2,1-c][1,4]benzodiazepine). Antibiotic DC 81 is potent inhibitor of nucleic acid synthesis. Antibiotic DC 81 can recognize and bind to specific sequences of DNA and form a labile covalent adduct[1][2].

Signaling Pathways >> Apoptosis >> Apoptosis

Research Areas >> Cancer

Signaling Pathways >> Cell Cycle/DNA Damage >> DNA/RNA Synthesis

Antibiotic DC 81 shows cytotoxicity against human melanoma cell lines B16, A375, A2058, and RPMI7951, with IC50 values of 4.4 μM, 18.5 μM, 31.0 μM, and 41.5 μM, respectively[1][2]. Antibiotic DC 81 exhibits its biological activity by covalently binding to the N2 of guanine in the minor groove of DNA, via the electrophilic carbinolamine functionality at N10-C11[1]. Antibiotic DC 81 (4 μM, 24 h) induces mitochondria dependent apoptosis[2]. Apoptosis Analysis[2] Cell Line: B16 melanoma cells Concentration: 4 μM Incubation Time: 24 h Result: Induced mitochondria dependent apoptosis.

Antibiotic DC 81 (0-10 mg/kg, i.p., at day 4, 7, 10, 13 after tumor cell injection) decreases the tumor burden in tumor-bearing mice, but the Antibiotic DC 81 at 10 mg/kg impairs cardiac muscle enzyme and liver function significantly[2]. Animal Model: Female C57BL/6 mice (8-12 weeks old, B16 cells were injected into the tail veins of mice)[2] Dosage: 0.1, 1, 10 mg/kg Administration: i.p., at day 4, 7, 10, 13 after tumor cell injection Result: Substantially decreased the tumor burden by 20% at 1 mg/kg. DC-81 at 10 mg/kg induced an 8-10-fold increase of GPT and a 6-8-fold increase in CPK, which indicated severe impaired liver function and muscle damage. Did not impair significant renal function as demonstrated by serum creatinine.

[1]. Hu WP, et al. Biological evaluation of an antibiotic DC-81-indole conjugate agent in human melanoma cell lines. Kaohsiung J Med Sci. 2003 Jan;19(1):6-12.  

[2]. Lee CH, et al. Pyrrolo[2,1-c][1,4]benzodiazepine and indole conjugate (IN6CPBD) has better efficacy and superior safety than the mother compound DC-81 in suppressing the growth of established melanoma in vivo. Chem Biol Interact. 2009 Aug 14;180(3):360-7.