Related Experiment Videos
Systemic interferon-alpha (IFN-alpha) treatment leads to Stat3 inactivation in melanoma precursor lesions
J M Kirkwood1, D L Farkas, A Chakraborty
1Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA.
Background:
In the setting of familial melanoma, the presence of atypical nevi, which are the precursors of melanoma, is associated with a nearly 100% risk of developing primary melanoma by age 70. In patients with sporadic melanoma, it is estimated that 40-60% of melanomas develop in contiguous association with atypical nevi. Currently, the only way to prevent atypical nevi from progressing to melanoma is to monitor and excise them as soon as they exhibit changes in their clinical features. Activation of the transcription factor, Stat3, has been linked to abnormal cell growth and transformation as well as to interferon alpha (IFN-alpha)-mediated growth suppression in vitro.
Materials And Methods:
To determine whether IFN-alpha, used for adjuvant therapy of high-risk, resected melanoma, induces changes in Stat3 in atypical nevi, patients with a clinical history of melanoma who have multiple atypical nevi were treated for 3 months with low-dose IFN-alpha. Thereupon, the new technology of microscopic spectral imaging and biochemical assays such as electrophoretic mobility shift assays (EMSAs) and immunoblot analysis were used for the study of atypical nevi, obtained before and after IFN-alpha treatment.
Results:
The results of the investigations provided evidence that, as a result of systemic IFN-alpha treatment, Stat1 and Stat3, which are constitutively activated in melanoma precursor lesions, lose their ability to bind DNA, and as shown in the case of Stat3, become dephosphorylated.
Conclusions:
Unlike primary and metastatic melanomas, melanoma precursor lesions cannot be established as cell cultures. Thus, the only way to explore pathways and treatment regimens that might help prevent progression to melanoma is within the context of a melanoma precursor lesion study conducted prospectively. The findings presented here suggest that down-regulation of the transcription factors Stat1 and Stat3 by systemic IFN-alpha treatment may represent a potential pathway to prevent the activation of gene(s) whose expression may be required for atypical nevus cells to progress to melanoma.
Insights
Interferon alpha (IFN-alpha) treatment may prevent melanoma development by down-regulating Stat1 and Stat3 transcription factors in atypical nevi, which are melanoma precursors. This research offers a potential new strategy for melanoma prevention.
Area of Science:
- Dermatology
- Oncology
- Molecular Biology
Background:
- Atypical nevi are precursors to melanoma, posing a high risk for familial melanoma patients and contributing to sporadic melanoma.
- Current prevention relies on monitoring and excising atypical nevi with changing clinical features.
- Constitutive activation of Stat3 is linked to abnormal cell growth and IFN-alpha-mediated growth suppression.
Purpose of the Study:
- To investigate if interferon alpha (IFN-alpha) treatment alters Stat3 activation in atypical nevi.
- To explore potential pathways for preventing melanoma progression from atypical nevi.
Main Methods:
- Patients with melanoma history and atypical nevi received low-dose IFN-alpha for 3 months.
- Microscopic spectral imaging and biochemical assays (EMSAs, immunoblot analysis) studied atypical nevi before and after treatment.
Main Results:
- Systemic IFN-alpha treatment led to dephosphorylation of Stat3.
- Constitutively activated Stat1 and Stat3 in melanoma precursor lesions lost their DNA-binding ability post-treatment.
Conclusions:
- Melanoma precursor lesions cannot be cultured, necessitating prospective studies for treatment exploration.
- Down-regulation of Stat1 and Stat3 by IFN-alpha may prevent gene activation required for atypical nevus progression to melanoma.
- IFN-alpha treatment shows potential as a preventative strategy against melanoma development from precursor lesions.