Molecular pathogenesis and targeted therapeutics in Ewing sarcoma/primitive neuroectodermal tumours

Area of Science:

• Oncology
• Molecular Biology
• Pharmacology

Background:

• Ewing sarcoma/PNET (Primitive Neuroectodermal Tumor) has a 5-year survival rate below 20% for metastatic or recurrent disease.
• Current treatments combine chemotherapy, surgery, and radiation, but outcomes for advanced cases remain poor.
• Molecularly targeted treatments represent a promising avenue for improving patient survival rates.

Purpose of the Study:

• To review the preclinical and clinical evidence for targeted therapeutics in Ewing sarcoma/PNET.
• To identify potential novel therapeutic strategies beyond conventional treatments.
• To assess the efficacy and challenges of emerging targeted therapies.

Main Methods:

• A comprehensive literature search of PubMed was conducted from 1997 to 2011.
• Referenced published literature on Ewing sarcoma/PNET.
• Focused on studies investigating molecularly targeted treatments.

Main Results:

• Insulin-like growth factor-1 receptor (IGF-1R) antagonists showed modest efficacy in early clinical trials.
• Antisense RNA and cDNA oligonucleotides targeting the EWS-FLI chimera have therapeutic potential but face delivery challenges.
• Inhibitors of RNA helicase A, histone deacetylase inhibitors, and cyclin-dependent kinase inhibitors (e.g., flavopiridol) show promise in preclinical models.
• Immunotherapy with natural killer cells and interferon-based therapies are also being explored.

Conclusions:

• Preclinical data strongly support the potential efficacy of targeted therapeutics for Ewing sarcoma/PNET.
• IGF-1R antagonists have shown clinical efficacy, though response prediction is challenging.
• Future treatment paradigms for Ewing sarcoma/PNET are expected to incorporate these scientific advances for improved outcomes.