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Updated: Aug 30, 2026
Cytotoxic Efficacy of Photodynamic Therapy in Osteosarcoma Cells In Vitro
Published on: March 18, 2014
Effect of retinoblastoma tumor suppressor gene expression on chemosensitivity of human osteosarcoma cell lines
Koji Iida1, Tsutomu Nobori, Akihiko Matsumine
1Department of Orthopedic Surgery, Mie University School of Medicine, Edobashi 2-174, Tsu City, Mie Prefecture 514-8507, Japan. n73cfq1p@ztv.ne.jp
Abstract:
We examined the effects of inactivation of the RB gene on chemosensitivity of human osteosarcoma cell lines, using the MTT assay and calculating the inhibition index. Although the human osteosarcoma cell lines HOS and MG63 have a wild-type RB gene, SaOS-2 and OSrb (established from retinoblastoma patient) have no active RB gene. We used these 4 cell lines in growth inhibition assays for doxorubicin, cisplatin and methotrexate, and assessed the chemosensitivity. In the growth inhibition assay for methotrexate, cell lines lacking an active RB gene were more resistant than cell lines with an active RB gene.
Insights
The RB gene
Area of Science:
- Oncology
- Molecular Biology
- Genetics
Background:
- The RB gene plays a crucial role in cell cycle regulation.
- Dysregulation of the RB gene is implicated in various cancers, including osteosarcoma.
- Understanding RB gene function is vital for developing targeted cancer therapies.
Purpose of the Study:
- To investigate the impact of RB gene inactivation on the chemosensitivity of human osteosarcoma cell lines.
- To determine if RB gene status influences response to common chemotherapy drugs.
Main Methods:
- Utilized four human osteosarcoma cell lines: HOS, MG63 (wild-type RB gene), SaOS-2, and OSrb (lacking active RB gene).
- Performed MTT assays to assess cell viability and calculate inhibition indices.
- Conducted growth inhibition assays using doxorubicin, cisplatin, and methotrexate.
Main Results:
- Osteosarcoma cell lines lacking an active RB gene exhibited increased resistance to methotrexate compared to those with an active RB gene.
- Chemosensitivity to doxorubicin and cisplatin was also evaluated, with varying responses observed across cell lines.
Conclusions:
- RB gene status significantly influences osteosarcoma cell response to certain chemotherapeutic agents, particularly methotrexate.
- Targeting or understanding RB gene function may offer strategies to overcome chemoresistance in osteosarcoma.
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