Cell experiment:

The cytotoxicity of 9-Aminocamptothecin is assessed by clonogenic assay. Exponentially growing cells are resuspended in media, cell number is determined using an electronic counter, and 100–250 cells are inoculated in triplicate onto 60 15-mm dishes containing 5 mL of medium. After an overnight incubation, 5 μL of 9-Aminocamptothecin stock solutions are added to the dishes to achieve final concentrations of 0, 0.27, 1.37, 2.74, 13.7, 27.4, 137, and 274 nM. After 4-, 8-, 12-, 24-, 48-, 72-, and 240-h exposures, medium is removed by aspiration and fresh medium is added to the dishes. Percentage of survival at each drug concentration with different exposure time is determined from the ratio of the number of the colonies in the drug-treated sample:the number in the control (DMSO vehicle-treated) sample[1].

Animal experiment:

Mice: Treatment with 9-Aminocamptothecin is started on day 7 after inoculation with KBM-3 cells. Five groups of 5 mice each (average weight of 22 g) are used and treatment is administered daily 4 days a week for 3 weeks as follows: 1) group 1 control mice are injected IV with PBS; 2) group 2 mice receive 1.33 mg/kg 9-Aminocamptothecin IV, 3) group 3 mice receive 1.33 mg/kg 9-Aminocamptothecin orally by gavage; 4) group 4 mice receive 2.0 mg/kg 9-Aminocamptothecin IV; 5) group 5 mice receive 2.0 mg/kg 9-Aminocamptothecin orally by gavage[3].

9-amino Camptothecin is a topoisomerase I inhibitor [1][2].

DNA topoisomerases relax DNA torsional strain generated during replication, transcription, recombination, repair, and chromosome condensation. The relaxation of DNA supercoiling by topoisomerase I is enabled by a mechanism of controlled rotation around a transient DNA single-strand break. Camptothecin (CPT) is isolated from the bark of the Chinese tree Camptotheca accuminata [3].

9-amino Camptothecin, a water-soluble camptothecin analogue, is a topoisomerase I inhibitor. In human HT-29 colon adenocarcinoma, 9-amino Camptothecin (9-AC) exhibited cytotoxicity with IC50 value of 19 nM. 9-AC also induced DNA damage in whole cells and nuclei at a concenstration of 85 nM and 21 nM, respectively [1].

9-amino Camptothecin had greater activity than camptothecin against human tumour xenografts, including Lewis lung carcinoma and B16 melanoma. 9-AC had entered phase II trials. In patients with advanced solid tumours, 9-amino Camptothecin exhibited anti-tumor activity [1][2].

References:
[1].  Rothenberg, M.L. Topoisomerase I inhibitors: Review and update. Annals of Oncology 8(9), 837-855 (1997).
[2].  Dancey J, Eisenhauer EA. Current perspectives on camptothecins in cancer treatment. Br J Cancer. 1996 Aug;74(3):327-38.
[3].  Drwal MN1, Agama K, Wakelin LP, et al. Exploring DNA topoisomerase I ligand space in search of novel anticancer agents. PLoS One. 2011;6(9):e25150.