TFF1 – a new Biomarker in Liquid Biopsies of Retinoblastoma under Therapy

Effective management of retinoblastoma (RB), the most prevalent childhood eye cancer, depends on reliable monitoring and diagnosis. A promising candidate in this context is the secreted trefoil family factor peptide 1 (TFF1), recently discovered as a promising new biomarker in patients with a more advanced subtype of retinoblastoma. The present study investigated TFF1 expression within aqueous humor (AH) of enucleated eyes and compared TFF1 levels in AH and corresponding blood serum samples from RB patients undergoing intravitreal chemotherapy (IVC). TFF1 was consistently detectable in AH, confirming its potential as a biomarker. Crucially, our data confirmed that TFF1 secreting cells within the tumor mass originate from RB tumor cells, not from surrounding stromal cells. IVC therapy responsive patients exhibited remarkably reduced TFF1 levels post-therapy. By contrast, RB patients’ blood serum displayed low to undetectable levels of TFF1 even after sample concentration and no therapy-dependent changes were observed. Our findings suggest that compared to blood serum AH represents the more reliable source for TFF1 if used for liquid biopsy RB marker analysis in RB patients. Thus, analysis of TFF1 in AH of RB patients potentially provides a minimal invasive tool for monitoring RB therapy efficacy, suggesting its importance for effective treatment regimens. Simple Summary Effective management of retinoblastoma (RB), a common childhood eye cancer, requires accurate diagnosis and monitoring during therapy. In this study the liquid biopsy marker potential of the secreted trefoil family factor peptide 1 (TFF1), described as a biomarker of a more advanced RB subtype, was explored. TFF1 expression levels were investigated in aqueous humor (AH) of RB patients after enucleation and in RB patients undergoing intravitreal chemotherapy and compared with TFF1 expression levels in RB patients’ blood serum. AH showed consistent TFF1 levels in a subgroup of RB patients, remarkably decreasing post-therapy in responsive patients. Blood serum of RB patients only displayed low to non-detectable and therapy-independent TFF1 levels. The study suggests TFF1 expression in AH as a reliable biomarker, aiding RB diagnosis and treatment assessment and highlights it’s potential for non-invasive RB therapy monitoring. ![Figure][1] ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Ethics committee of the University of Duisburg- Essen, Medical Faculty gave ethical approval for this work (approval number 14-5836-BO). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present work are contained in the manuscript [1]: pending:yes