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Updated: Aug 9, 2026
Reconstruct Human Retinoblastoma In Vitro
Published on: October 11, 2022
Immunohistochemical detection of multidrug-resistant protein expression in retinoblastoma treated by primary
Matthew W Wilson1, Charles H Fraga, Christine E Fuller
1Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, Tennessee, USA. mwilson5@utmem.edu
Purpose:
To compare the expression of multidrug-resistant proteins in retinoblastoma tumors among eyes treated with primary enucleation.
Methods:
A group of 18 patients with unilateral retinoblastoma with advanced intraocular disease was selected for the study. All patients had undergone primary enucleation. A histologic specimen from each patient was retrieved from the pathology archives and a tissue gene microarray was constructed (0.6 x 3-4 mm). Standard immunohistochemical techniques were used to study the tissue microarrays for the expression of the ATP-binding cassette (ABC) transporters: breast cancer resistance protein (BCRP; ABCG2), multidrug-resistant protein 1/P-glycoprotein (MDR1/Pgp; ABCB1), multidrug-resistant-associated protein 1 (MRP1; ABCC1), MRP2 (ABCC2), and MRP4 (ABCC4).
Results:
Of the 18 specimens retrieved, 16 had adequate tissue for study. MRP1 was expressed in 8 (50%) of 16 tumors, and MRP2 was expressed in 5 (31%) of 16 tumors. MDR1/Pgp was found in 2 (12%) of 16 retinoblastomas. MRP4 and BCRP were not detected in any of the tumors studied.
Conclusions:
The results show that multiple ABC transporters were present in a cohort of sporadic patients with unilateral retinoblastoma who underwent primary enucleation. Studies are planned of the expression of ABC transporters in eyes treated by chemotherapy and/or radiation as a comparison with this group.
Insights
Multidrug-resistant proteins, including MRP1 and MRP2, were found in retinoblastoma tumors from patients who had primary enucleation. Further studies will compare these findings with tumors treated by chemotherapy or radiation.
Area of Science:
- Ophthalmology
- Oncology
- Molecular Biology
Background:
- Retinoblastoma is a pediatric eye cancer.
- Multidrug resistance proteins (MRPs) are implicated in treatment failure.
- Understanding MRP expression is crucial for retinoblastoma management.
Purpose of the Study:
- To investigate the expression of ATP-binding cassette (ABC) transporters in retinoblastoma tumors.
- To compare MRP expression in eyes treated with primary enucleation.
Main Methods:
- Histologic specimens from 16 patients with unilateral retinoblastoma were analyzed.
- Immunohistochemical techniques were used to detect ABC transporters.
- Specific transporters studied included BCRP, MDR1/Pgp, MRP1, MRP2, and MRP4.
Main Results:
- Multidrug resistance-associated protein 1 (MRP1) was expressed in 50% of tumors.
- Multidrug resistance protein 2 (MRP2) was detected in 31% of tumors.
- MDR1/Pgp was found in 12% of retinoblastomas; MRP4 and BCRP were not detected.
Conclusions:
- Multiple ABC transporters are present in retinoblastoma tumors post-enucleation.
- These findings highlight the potential role of MRPs in retinoblastoma.
- Future studies will compare these results with MRP expression in tumors treated with chemotherapy and/or radiation.
