CLM3, a multitarget tyrosine kinase inhibitor with antiangiogenic properties, is active against primary anaplastic thyroid cancer in vitro and in vivo

J Clin Endocrinol Metab. 2014 Apr;99(4):E572-81. doi: 10.1210/jc.2013-2321. Epub 2014 Jan 1.


Context and objective: We have studied the antitumor activity of a pyrazolo[3,4-d]pyrimidine compound (CLM3) proposed for a multiple signal transduction inhibition [including the RET tyrosine kinase, epidermal growth factor receptor, and vascular endothelial growth factor (VEGF) receptor and with antiangiogenic activity] in primary anaplastic thyroid cancer (ATC) cells, in the human cell line 8305C (undifferentiated thyroid cancer), and in an ATC-cell line (AF).

Design and main outcome measures: CLM3 was tested in primary ATC cells at the concentrations of 5, 10, 30, and 50 μM; in 8305C cells, in AF cells, at 1, 5, 10, 30, 50, or 100 μM; and in AF cells in CD nu/nu mice.

Results: CLM3 significantly inhibited the proliferation of 8305C and AF cells, also inducing apoptosis. A significant reduction of proliferation with CLM3 in ATC cells (P < .01, ANOVA) was shown. CLM3 increased the percentage of apoptotic ATC cells dose dependently (P < .001, ANOVA) and inhibited migration (P < .01) and invasion (P < .001). The AF cell line was injected sc in CD nu/nu mice, and tumor masses became detectable 15 days later. CLM3 (50 mg/kg per die) significantly inhibited tumor growth (starting 16 d after the beginning of treatment). CLM3 significantly decreased the VEGF-A expression and microvessel density in AF tumor tissues. Furthermore, CLM3 inhibited epidermal growth factor receptor, AKT, and ERK1/2 phosphorylation and down-regulated cyclin D1 in 8305C and AF cells.

Conclusions: The antitumor and antiangiogenic activity of a pyrazolo[3,4-d]pyrimidine compound (CLM3) is very promising in anaplastic thyroid cancer, opening the way to a future clinical evaluation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiogenesis Inhibitors / therapeutic use*
  • Animals
  • Humans
  • Male
  • Mice
  • Mice, Nude
  • Neovascularization, Pathologic / drug therapy
  • Protein Kinase Inhibitors / therapeutic use
  • Protein-Tyrosine Kinases / antagonists & inhibitors
  • Pyrazoles / therapeutic use*
  • Pyrimidines / therapeutic use*
  • Thyroid Carcinoma, Anaplastic
  • Thyroid Neoplasms / blood supply
  • Thyroid Neoplasms / drug therapy*
  • Thyroid Neoplasms / pathology
  • Treatment Outcome
  • Tumor Cells, Cultured
  • Xenograft Model Antitumor Assays


  • Angiogenesis Inhibitors
  • CLM3 compound
  • Protein Kinase Inhibitors
  • Pyrazoles
  • Pyrimidines
  • Protein-Tyrosine Kinases