Preclinical Development of a Recombinant Toxin Containing Circularly Permuted Interleukin 4 and Truncated Pseudomonas Exotoxin for Therapy of Malignant Astrocytoma

Cancer Res. 1996 Dec 15;56(24):5631-7.


Effective treatment is lacking for malignant glioblastoma/astrocytoma. We have identified interleukin-4 receptors (IL-4R) on human malignant astrocytoma. We demonstrate that 16 of 21 surgical samples of high-grade astrocytoma and glioblastoma but not normal brain tissues expressed IL-4R as assessed by reverse transcriptase PCR. We further demonstrate that human malignant astrocytoma cell lines express high-affinity IL-4R. Using a chimeric protein composed of circularly permuted IL-4 and a truncated form of Pseudomonas exotoxin A, we observed that this toxin IL4(38-37)-PE38KDEL) is highly cytotoxic to IL-4R-bearing glioblastoma cells. Compared with a previously reported IL4-PE chimeric protein (IL-PE4E), IL4(38-37)-PE38KDEL bound with higher affinity and was 3-30-fold more cytotoxic to glioblastoma cell lines. Upon intrathecal administration in monkeys, high cerebrospinal fluid IL4(38-37)-PE38KDEL levels were achieved using 2- and 6-microg/kg doses without any central nervous system or other abnormalities. IL4(38-37)-PE38KDEL levels were not detectable in the serum of any monkey studied. When IL4(38-37)-PE38KDEL was injected into the right frontal cortex of rats, localized necrosis was observed at 1000-ng/ml doses but not at < or = 100-ng/ml doses. We conclude that by localized administration, nontoxic levels of IL4(38-37)-PE38KDEL can be achieved, which may have significant cytotoxic activity against malignant astrocytoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ADP Ribose Transferases*
  • Animals
  • Antineoplastic Agents / adverse effects
  • Antineoplastic Agents / pharmacokinetics
  • Antineoplastic Agents / therapeutic use*
  • Astrocytoma / drug therapy*
  • Astrocytoma / metabolism
  • Bacterial Toxins / adverse effects
  • Bacterial Toxins / pharmacokinetics
  • Bacterial Toxins / therapeutic use*
  • Brain Neoplasms / drug therapy*
  • Brain Neoplasms / metabolism
  • Drug Screening Assays, Antitumor
  • Exotoxins / adverse effects
  • Exotoxins / pharmacokinetics
  • Exotoxins / therapeutic use*
  • Female
  • Humans
  • Immunotoxins / adverse effects
  • Immunotoxins / pharmacokinetics
  • Immunotoxins / therapeutic use*
  • Injections, Spinal
  • Interleukin-4 / adverse effects
  • Interleukin-4 / metabolism
  • Interleukin-4 / pharmacokinetics
  • Interleukin-4 / therapeutic use*
  • Macaca fascicularis
  • Rats
  • Rats, Sprague-Dawley
  • Recombinant Fusion Proteins / adverse effects
  • Recombinant Fusion Proteins / pharmacokinetics
  • Recombinant Fusion Proteins / therapeutic use*
  • Tumor Cells, Cultured
  • Virulence Factors*


  • Antineoplastic Agents
  • Bacterial Toxins
  • Exotoxins
  • Immunotoxins
  • Recombinant Fusion Proteins
  • Virulence Factors
  • Interleukin-4
  • ADP Ribose Transferases
  • toxA protein, Pseudomonas aeruginosa