Cdh11 acts as a tumor suppressor in a murine retinoblastoma model by facilitating tumor cell death

Area of Science:

• Oncology
• Genetics
• Ophthalmology

Background:

• CDH11 gene copy number and expression are frequently lost in human retinoblastomas.
• Loss of CDH11 is observed in retinoblastomas arising in TAg-RB mouse models.

Purpose of the Study:

• To investigate the effect of CDH11 loss on retinoblastoma tumorigenesis.
• To determine the role of CDH11 in tumor suppressor mechanisms.

Main Methods:

• Crossed Cdh11 null mice with TAg-RB mice to study tumorigenesis.
• Analyzed retinal volume, TAg-positive cell counts, tumor multiplicity, and tumor growth rates.
• Assessed cell death and proliferation in vivo and in vitro using specific markers.

Main Results:

• Loss of Cdh11 led to larger retinal volumes and faster tumor growth in TAg-RB mice.
• Cdh11-null mice showed fewer TAg-positive cells and multifocal tumors initially, but accelerated tumor growth later.
• Tumors in Cdh11-null mice exhibited decreased cell death (5- to 10-fold) but unaffected proliferation.
• In vitro, Cdh11 knockdown decreased activated caspase-3 and increased beta-catenin expression.

Conclusions:

• CDH11 exhibits tumor suppressor properties in retinoblastoma.
• CDH11 promotes cell death in retinoblastoma, both in vivo and in vitro.
• CDH11 loss contributes to retinoblastoma progression by reducing apoptosis.