Cell lines

MDA-MB-231 and MCF-7 cells

Preparation method

This compound is soluble in DMSO. General tips for obtaining a higher concentration: Please warm the tube at 37℃ for 10 minutes and/or shake it in the ultrasonic bath for a while. Stock solution can be stored below -20℃ for several months.

Reaction Conditions

500, 600, 700 and 800 μg/mL; 24, 48 and 72 hrs

Applications

In MDA-MB-231 and MCF-7 cells as well as their long-term Tamoxifen-resistant clones, Oseltamivir treatment dose-dependently reduced the sialidase activity associated with EGF-stimulated live cells and the cell viability after 72 hrs of incubation. Combination of 1 μM Cisplatin, 5-FU, Paclitaxel, Gemcitabine or Tamoxifen with Oseltamivir (≥ 300 μg/ mL) significantly reduced cell viability at 24, 48 and 72 hrs when compared to the chemodrug alone.

Animal models

RAGxCγ double mutant mice bearing heterotopic xenografts of MDA-MB-231 tumors

Dosage form

30 and 50 mg/kg; i.p.

Applications

Compared with the untreated cohorts, Oseltamivir treatment (30 mg/kg, q.d., i.p.) reduced tumor vascularization and growth rate, as well as significantly reduced tumor weight and spread to the lungs. At the dosage of 50 mg/kg, Oseltamivir completely ablated tumor vascularization, tumor growth and spread to the lungs, with significant long-term survival at day 180 postimplantation, tumor shrinking, and no relapses after 56 days off-drug.

Other notes

Please test the solubility of all compounds indoor, and the actual solubility may slightly differ with the theoretical value. This is caused by an experimental system error and it is normal.

Oseltamivir is an inhibitor of influenza neuraminidase [1].
Oseltamivir is a prodrug that is converted by intestinal and/or hepatic esterases to the neuraminidase inhibitor molecule, oseltamivir carboxylate. Neuraminidase cleaves the terminal a-Neu5Ac residues from the newly synthesized virion progeny and let it elute from the infected cell and seek new host cells to infect. Oseltamivir efficiently block sialidase activity and significantly inhibit the releasing mechanism [1].
In the treatment of adults, oseltamivir reduces the time to first alleviation of symptoms and investigator mediated unverified pneumonia. In prophylaxis trials, oseltamivir reduced symptomatic influenza in participants by 55%. Oseltamivir also has some harm. Adults treated with oseltamivir are associated with an increased risk of nausea. And in prophylaxis trials there is an increased risk of headaches on-treatment [2].
As a neuraminidase inhibitor, the substitution of the amino acid histidine to tyrosine at position 275 (H275Y) in the neuraminidase gene of H1N1 can cause the resistance of oseltamivir [3].
References:
[1]. Enguang Feng, Deju Ye, Jian Li, Dengyou Zhang, Jinfang Wang, Fei Zhao, Rolf Hilgenfeld, Mingyue Zheng, Hualiang Jiang and Hong Liu. Recent Advances in Neuraminidase Inhibitor Development as Anti-influenza Drugs. Chem Med Chem, 2012, 7: 1527-1536.
[2]. Tom Jefferson reviewer, Mark Jones, Peter Doshi, Elizabeth A Spencer, Igho Onakpoya, Carl J Heneghan. Oseltamivir for influenza in adults and children: systematic review of clinical study reports and summary of regulatory comment. BMJ, 2014, 348: g2545.
[3]. Rashmi Dixit, Gulam Khandaker, Scott Ilgoutz, Harunor Rashid and Robert Booy. Emergence of Oseltamivir Resistance: Control and Management of Influenza before, during and after the Pandemic. Infectious Disorders-Drug Targets. 2013, 13 (1): 34-45.