Carcinoma homing peptide (chp), its analogs, and methods of using

Abstract

A mini-peptide and its analogs have been found to target gene products to tumors. The peptide, named Carcinoma Homing Peptide (CHP), increased the tumor accumulation of the reporter gene products in five independent tumor models, including one human xenogeneic model. A CHP-IL-12 fusion gene was also developed using CHP and the p40 subunit of IL-12. The product from CHP-IL-12 fusion gene therapy increased accumulation of IL-12 in the tumor environment. In three tumor models. CHP-IL-12 gene therapy inhibited distal tumor growth. In a spontaneous lung metastasis model, inhibition of metastatic tumor growth was improved compared to wild-type IL-12 gene therapy, and in a squamous cell carcinoma model, toxic liver lesions were reduced. The receptor for CHP was identified as vimentin. CHP can be used to improve the efficacy and safety of targeted cancer treatments.

1 . A tumor-targeting conjugate comprising an agent conjugated to a carcinoma homing peptide (CHP) consisting of SEQ ID NO:1. 
     
     
         2 . The tumor-targeting conjugate of  claim 1 , wherein the agent is a reporter peptide or a protein tag or an antitumor therapeutic agent. 
     
     
         3 . The tumor-targeting conjugate of  claim 2 , wherein the reporter protein is secreted alkaline phosphatase. 
     
     
         4 . The tumor-targeting conjugate of  claim 2 , wherein the protein tag is biotin. 
     
     
         5 . The tumor-targeting conjugate of  claim 2 , wherein the anti-tumor therapeutic agent is a cytokine. 
     
     
         6 . A composition comprising the tumor targeting conjugate of  claim 1 . 
     
     
         7 . The tumor-targeting conjugate of  claim 1 , prepared by a method comprising conjugating the agent to the carcinoma homing peptide (CHP) consisting of SEQ ID NO:1. 
     
     
         8 . A method for targeting an agent to a vimentin-expressing cell comprising contacting the vimentin-expressing cell with a tumor targeting conjugate comprising the agent conjugated to a carcinoma homing peptide (CHP) consisting of SEQ ID NO:1,
 wherein the CHP binds to the vimentin.   
     
     
         9 . The method of  claim 8 , wherein the agent is an anti-tumor therapeutic agent. 
     
     
         10 . The method of  claim 9 , wherein the anti-tumor therapeutic agent is a cytokine. 
     
     
         11 . The method of  claim 9 , wherein the cytokine is interleukin 12. 
     
     
         12 . The method of  claim 9 , wherein the anti-tumor therapeutic agent is a p40 subunit of interleukin 12. 
     
     
         13 . The method of  claim 8 , wherein the tumor targeting conjugate comprises an amino acid sequence of SEQ ID NO:3. 
     
     
         14 . The method of  claim 8 , wherein the tumor targeting conjugate is encoded by a nucleotide sequence comprising the nucleotide sequence of SEQ ID NO:2. 
     
     
         15 . A method of determining the presence of a vimentin protein on a surface of a cell comprising:
 contacting the cell with a tumor targeting conjugate comprising a peptide conjugated to a carcinoma homing peptide (CHP) consisting of SEQ ID NO:1 wherein the tumor targeting conjugate binds to the vimentin protein; and   assaying the cell for the presence of a bound tumor targeting conjugate such that the presence of the bound tumor targeting conjugate correlates with the presence of the vimentin protein on the cell.   
     
     
         16 . The method of  claim 15 , wherein the first peptide is a reporter peptide or a protein tag. 
     
     
         17 . The method of  claim 16 , wherein the reporter peptide is secreted alkaline phosphatase. 
     
     
         18 . The method of  claim 16 , wherein the protein tag is biotin. 
     
     
         19 . The method of  claim 15 , wherein the cell is from a biological sample from a mammal. 
     
     
         20 . The method of  claim 19 , further comprising
 determining an amount of the vimentin protein present on the cell; and   comparing the amount of the vimentin protein present on the cell to a control amount of vimentin protein present on a control cell,   wherein the presence of an increased amount of the vimentin protein present on the cell as compared with the control amount indicates that the cell is cancerous.