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Published on: March 18, 2014
In vitro retinoid-induced growth inhibition and morphologic differentiation of canine osteosarcoma cells
S H Hong1, T Kadosawa, K Nozaki
1Division of Veterinary Medical Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan.
Objective:
To determine differentiation and growth inhibition effects of retinoids on canine osteosarcoma cells.
Sample Population:
3 osteosarcoma cell lines established from osteosarcomas in dogs.
Procedure:
Osteosarcoma cells were incubated with various concentrations of all-trans-retinoic acid and 9-cis-retinoic acid or control medium, counted daily for 10 days, and evaluated for morphologic changes. Synthesis of DNA was measured by use of a cell proliferation ELISA. To analyze effect of retinoids on colony formation on plastic dishes, cells were cultured for 14 days, fixed, and stained; number of colonies was counted.
Results:
In a dose-dependent manner, both retinoids induced morphologic differentiation and growth inhibition in the 3 osteosarcoma cell lines and inhibited each cell's ability to form anchorage-dependent colonies.
Conclusion And Clinical Relevance:
Retinoids induced differentiation of osteosarcoma cells of dogs, resulting in altered expression of their malignant phenotype. Induction of differentiation by retinoids may have potential as an adjunctive treatment for osteosarcoma in dogs.
Insights
Retinoids like all-trans-retinoic acid and 9-cis-retinoic acid were found to inhibit growth and induce differentiation in canine osteosarcoma cells. This suggests retinoids may offer potential as an adjunctive therapy for canine osteosarcoma.
Area of Science:
- Veterinary Oncology
- Molecular Biology
- Cancer Research
Background:
- Canine osteosarcoma is an aggressive bone cancer with limited treatment options.
- Retinoids are known to regulate cell differentiation and proliferation.
Purpose of the Study:
- To investigate the effects of retinoids on canine osteosarcoma cell differentiation and growth.
- To evaluate the potential of retinoids as a therapeutic agent for canine osteosarcoma.
Main Methods:
- Utilized three established canine osteosarcoma cell lines.
- Treated cells with varying concentrations of all-trans-retinoic acid and 9-cis-retinoic acid.
- Assessed cell morphology, DNA synthesis (proliferation), and anchorage-dependent colony formation.
Main Results:
- Retinoids demonstrated a dose-dependent induction of morphologic differentiation in all tested cell lines.
- Both retinoids significantly inhibited cell growth and proliferation.
- Retinoid treatment reduced the ability of osteosarcoma cells to form colonies.
Conclusions:
- Retinoids effectively induce differentiation and inhibit growth of canine osteosarcoma cells.
- Altered malignant phenotype expression was observed following retinoid treatment.
- Retinoid-induced differentiation shows promise as a potential adjunctive treatment strategy for canine osteosarcoma.
