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Updated: Jun 3, 2026
08:49
A 3D Organotypic Melanoma Spheroid Skin Model
Published on: May 18, 2018
Malignancy without immortality? Cellular immortalization as a possible late event in melanoma progression
Julia K Soo1, Alastair D Mackenzie Ross, David M Kallenberg
1Division of Biomedical Sciences, St. George's, University of London, UK.
Pigment Cell & Melanoma Research
|March 23, 2011
Summary
Primary melanoma cultures are typically precrisis, with immortalization and telomere maintenance occurring late. Benign nevi cultures consistently showed senescence, not immortality.
Area of Science:
- Oncology
- Cell Biology
- Dermatology
Background:
- Cell senescence is a permanent growth arrest.
- Cultured cancer cells, including melanoma, often appear immortal.
- Uncultured benign nevi typically display senescence markers.
Purpose of the Study:
- Investigate which primary pigmented lesions are typically immortal using new explantation methods.
- Characterize senescence and immortalization markers in nevi and melanoma.
- Determine the stage of immortalization in primary melanomas.
Main Methods:
- Utilized novel explantation techniques for primary pigmented lesions.
- Cultured benign nevi and primary melanomas.
- Assessed cultures for senescence markers (β-galactosidase, nuclear p16, heterochromatic foci) and telomeric crisis markers (anaphase bridges).
- Quantified telomerase reverse transcriptase and telomerase expression in immortal melanoma cultures.
Main Results:
- No benign nevus cultures (0/28) were immortal; most nevus cells showed senescence.
- A minority of melanoma cultures (4/37) were immortal.
- Arrested cultures exhibited senescence markers, while melanomas also showed telomeric crisis features.
- Immortal melanoma cultures expressed telomerase and displayed aneuploidy.
Conclusions:
- Primary melanomas are generally precrisis.
- Immortalization and telomere maintenance represent late events in melanoma progression.
- Benign nevi are consistently senescent and not immortal.
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