Anti-tumor effects of shikonin derivatives on human medullary thyroid carcinoma cells

Area of Science:

• Biochemistry
• Pharmacology
• Oncology

Background:

• Medullary thyroid carcinoma (MTC) is a neuroendocrine tumor with high metastatic potential.
• MTC exhibits resistance to conventional radiotherapy and chemotherapy, necessitating novel therapeutic strategies.

Purpose of the Study:

• To investigate the efficacy of shikonin derivatives as potential treatments for medullary thyroid carcinoma.
• To evaluate the selective toxicity of shikonin derivatives against MTC cells compared to normal fibroblasts.

Main Methods:

• Screening of shikonin derivatives (acetylshikonin, β,β-dimethylacrylshikonin, shikonin) and an Onosma paniculata root extract for anti-cancer activity.
• Assessing inhibition of cell proliferation, viability, migration, and invasion in the MTC cell line TT.
• Evaluating in vivo efficacy using the chick chorioallantoic membrane (CAM) assay for shikonin.

Main Results:

• Shikonin derivatives, particularly unsubstituted shikonin (IC50 = 1.1 µM), significantly inhibited proliferation and viability of TT cells.
• Shikonin derivatives demonstrated selective toxicity, sparing normal human skin fibroblasts.
• Non-toxic concentrations of shikonin derivatives reduced MTC cell migration and invasion.
• In vivo studies on the CAM assay showed shikonin significantly reduced tumor growth by inhibiting proliferation and inducing apoptosis.

Conclusions:

• Shikonin derivatives exhibit potent anti-cancer properties against medullary thyroid carcinoma cells.
• These compounds show potential for selective targeting of MTC cells, minimizing harm to healthy tissues.
• Shikonin derivatives represent a promising therapeutic avenue for medullary thyroid carcinoma treatment.