Related Experiment Video
Updated: Aug 22, 2026
Reconstruct Human Retinoblastoma In Vitro
Published on: October 11, 2022
Expression of Fas ligand in retinoblastoma
Subramanian Krishnakumar1, Mallikarjuna Kandalam, Adithi Mohan
1Department of Ocular Pathology, Vision Research Foundation, Sankara Nethralaya, Chennai, Tamil Nadu, India. drkrishnakumar_2000@yahoo.com
Background:
The importance of the Fas-Fas ligand (FasL) mechanism for the immune evasion by tumors provided a strong rationale for the examination of FasL expression in retinoblastoma. In an earlier publication, the authors reported that invasive retinoblastomas decreased Fas expression. Because to the authors' knowledge there is not much information regarding the effect of FasL expression on retinoblastoma, the authors studied the expression of FasL in retinoblastoma and correlated it with invasiveness.
Methods:
Thirty-six archival retinoblastoma specimens were divided into 2 groups. Group A (n = 17) was comprised of specimens from tumors with no invasion and Group B (n = 19) was comprised of specimens from tumors with invasion of the choroid (focal, diffuse), optic nerve (laminar, postlaminar, surgical end), and orbit. Sections were immunostained with a monoclonal antibody to FasL and the immunoreactivity was assessed.
Results:
In Group A, FasL was negative in 100% (17 of 17) of the tumor specimens. In Group B, FasL was expressed in 79% (15 of 19) of the tumor specimens (positive in 9 tumors and heterogeneous in 6 tumors). The difference in FasL expression between the two groups was significant (P < 0.001)
Conclusions:
Increased expression of FasL was observed in specimens taken from patients with aggressive tumors. Thus, Loss of Fas and gain of aberrant FasL expression were common features of malignant transformation. The data suggested that the Fas/FasL pathway is potentially immunosuppressive and may be involved in the escape of retinoblastoma cells from immune destruction.
Insights
Retinoblastoma tumors with invasion showed increased Fas ligand (FasL) expression compared to non-invasive tumors. This suggests the Fas/FasL pathway may aid tumor immune evasion in aggressive retinoblastoma.
Area of Science:
- Oncology
- Immunology
- Ophthalmology
Background:
- The Fas-Fas ligand (FasL) pathway is crucial for immune regulation and tumor immune evasion.
- Previous studies indicated decreased Fas expression in invasive retinoblastomas.
- Limited information exists on FasL expression's role in retinoblastoma invasiveness.
Purpose of the Study:
- To investigate FasL expression in retinoblastoma specimens.
- To correlate FasL expression levels with tumor invasiveness.
Main Methods:
- Analysis of 36 archival retinoblastoma specimens (17 non-invasive, 19 invasive).
- Immunohistochemical staining for FasL using a monoclonal antibody.
- Assessment of FasL immunoreactivity in relation to tumor invasion (choroid, optic nerve, orbit).
Main Results:
- FasL was negative in all 17 non-invasive retinoblastoma specimens (Group A).
- FasL was expressed in 79% of invasive retinoblastoma specimens (15 of 19, Group B).
- A statistically significant difference (P < 0.001) in FasL expression was observed between invasive and non-invasive tumors.
Conclusions:
- Increased FasL expression is associated with aggressive retinoblastoma tumors.
- Aberrant FasL expression, alongside Fas loss, is a common feature of malignant retinoblastoma.
- The Fas/FasL pathway may contribute to retinoblastoma's immunosuppressive properties and immune escape.
