Methods of determining interferon having direct inhibitory effects on tumors and uses thereof

Abstract

The invention provides novel methods of determining or comparing potency of a test interferon relative to rSIFN-co (an interferon having therapeutic effects on solid tumors); methods of establishing substantial equivalence between a test interferon and rSIFN-co; as well as methods for determining potency of a test interferon, kits for determination of such methods, and an interferon or an interferon substitute having said activities.

1 - 89 . (canceled) 
     
     
         90 . A method of determining or comparing potency of a test interferon relative to Recombinant Super-Compound Interferon (rSIFN-co), or establishing substantial equivalence between a test interferon and rSIFN-co, comprising the steps of:
 (1) providing a first sample, a second sample and a third sample of cancer cells of the same type;   (2) treating the first sample with the test interferon, treating the second sample with rSIFN-co, and using the third sample as a control sample; and   (3) measuring susceptibility to inhibition by B18R of said test interferon and rSIFN-co in up-regulation of expression of p-STAT in cancer cells in the first, second and third samples;   wherein similar susceptibility to inhibition by B18R in up-regulation of expression of p-STAT indicates substantial equivalence between the test interferon and the rSIFN-co.   
     
     
         91 . The method of  claim 90 , wherein the cancer cells comprise any one or more of: lung cancer cells, colon cancer cells, cervical cancer cells, liver cancer cells, breast cancer cells, and pancreatic cancer cells. 
     
     
         92 . The method of  claim 90 , wherein the cancer cells are A549 cells or Hela cells. 
     
     
         93 . The method of  claim 90 , wherein said test interferon and rSIFN-co are incubated with B18R in a range of about 5 ng/ml to about 20 ng/ml before contacting the cancer cells. 
     
     
         94 . The method of  claim 93 , wherein said test interferon, after incubating with B18R at 10 ng/ml, shows greater induction of phosphorylation on STAT1/2/3 in A549 cells and Hela cells as compared to the third sample containing IFNα-2b. 
     
     
         95 . The method of  claim 90 , wherein the up-regulation of p-STAT expression is determined by Western Blot. 
     
     
         96 . The method of  claim 90 , wherein the test interferon has an amino acid sequence that is at least 90% identical to SEQ ID NO: 1. 
     
     
         97 . The method of  claim 90 , wherein the test interferon is encoded by a nucleotide sequence that is at least 90% identical to SEQ ID NO: 2. 
     
     
         98 . The method of  claim 90 , wherein the test interferon and rSIFN-co have the same amino acid sequence of SEQ ID NO: 1, and are encoded by the same nucleotide sequence of SEQ ID NO: 2. 
     
     
         99 . The method of  claim 90 , wherein the test interferon and rSIFN-co have substantially the same specific activity. 
     
     
         100 . The method of  claim 99 , wherein the specific activity is in the range between about 4×10 8  IU/mg and about 1×10 9  IU/mg.