Use of Patient-Derived Organoids as a Treatment Selection Model for Colorectal Cancer: A Narrative Review.

Surgical resection is the mainstay in intended curative treatment of colorectal cancer (CRC) and may be accompanied by adjuvant chemotherapy. However, 40% of the patients experience recurrence within five years of treatment, highlighting the importance of improved, personalized treatment options. Monolayer cell cultures and murine models, which are generally used to study the biology of CRC, are associated with certain drawbacks; hence, the use of organoids has been emerging. Organoids obtained from tumors display similar genotypic and phenotypic characteristics, making them ideal for investigating individualized treatment strategies and for integration as a core platform to be used in prediction models. Here, we review studies correlating the clinical response in patients with CRC with the therapeutic response in patient-derived organoids (PDO), as well as the limitations and potentials of this model. The studies outlined in this review reported strong associations between treatment responses in the PDO model and clinical treatment responses. However, as PDOs lack the tumor microenvironment, they do not genuinely account for certain crucial characteristics that influence therapeutic response. To this end, we reviewed studies investigating PDOs co-cultured with tumor-infiltrating lymphocytes. This model is a promising method allowing evaluation of patient-specific tumors and selection of personalized therapies. Standardized methodologies must be implemented to reach a "gold standard" for validating the use of this model in larger cohorts of patients. The introduction of this approach to a clinical scenario directing neoadjuvant treatment and in other curative and palliative treatment strategies holds incredible potential for improving personalized treatment and its outcomes.

Apoptosis and the FLIP and NF-kappa B proteins as pharmacodynamic criteria for biosimilar TNF-alpha antagonists.

Various criteria are necessary to assess the efficacy and safety of biological medications in order to grant companies the right to register these medications with the appropriate bodies that regulate their sale. The imminent expiration of the patents on reference biological products which block the cytokine TNF-α (tumor necrosis factor-α) raises the possibility of bringing so-called biosimilars to the market (similar to the biologicals of reference products). This occurrence is inevitable, but criteria to adequately evaluate these medications are now needed. Even among controversy, there is a demand from publications correlating the pro-apoptotic mechanism of the original TNF-α antagonists (etanercept, infliximab, adalimumab, golimumab, and certolizumab pegol) in the treatment of rheumatoid arthritis and other diseases. In this article, the authors discuss the possibility of utilizing the pro-apoptotic effect correlated with the regulation of the anti-apoptotic proteins FLIP and NF-κB as new criteria for analyzing the pharmacodynamics of possible biosimilar TNF-α antagonists which should be submitted to regulatory agencies for evaluation.