Model Selection for the Preclinical Development of New Drug-Radiotherapy Combinations

The n-Butanol Extract Obtained from the Inner Bark of Tabebuia rosea (Bertol.) DC, Specioside, and Catalposide Induce Leukemia Cell Apoptosis in the Presence of Apicidin

The cell signaling pathways involved in the antiproliferative activities of T. rosea inner bark remain unexplored. This study evaluated the apoptotic effects of two iridoids from the inner bark of T. rosea and apicidin on THP-1 cells. The cytotoxic effects of the extract and the pure compounds on THP-1 and Jurkat cells were also evaluated using the MTT assay. The apoptotic effect was determined by measuring the mitochondrial membrane potential. The expression of mRNA and MAPK kinase, Bax, and Bcl-2 proteins was detected by Western blotting and RT-qPCR, respectively. The extract and the compounds evaluated increased the percentage of apoptotic cells. Depolarization of the mitochondrial membrane was observed, and the number of cells in the G0/G1 phase increased. Catalposide and specioside significantly increased p38 protein expression, mostly in cells pretreated with apicidin. The p38 MAPK signaling pathway is at least one of the pathways by which the n-butanol extract obtained from Tabebuia rosea, catalposide, and specioside exerts its apoptotic effect on THP-1 cells, and this effect generates a response in the G0/G1 phase and subsequent cell death. In addition, there was depolarization of the mitochondrial membrane, an effect that was related to the participation of the proapoptotic protein Bax.

Advances of Patient-Derived Organoids in Personalized Radiotherapy

Patient-derived organoids (PDO), based on the advanced three-dimensional (3D) culture technology, can provide more relevant physiological and pathological cancer models, which is especially beneficial for developing and optimizing cancer therapeutic strategies. Radiotherapy (RT) is a cornerstone of curative and palliative cancer treatment, which can be performed alone or integrated with surgery, chemotherapy, immunotherapy, or targeted therapy in clinical care. Among all cancer therapies, RT has great local control, safety and effectiveness, and is also cost-effective per life-year gained for patients. It has been reported that combing RT with chemotherapy or immunotherapy or radiosensitizer drugs may enhance treatment efficacy at faster rates and lower cost. However, very few FDA-approved combinations of RT with drugs or radiosensitizers exist due to the lack of accurate and relevant preclinical models. Meanwhile, radiation dose escalation may increase treatment efficacy and induce more toxicity of normal tissue as well, which has been studied by conducting various clinical trials, very expensive and time-consuming, often burdensome on patients and sometimes with controversial results. The surged PDO technology may help with the preclinical test of RT combination and radiation dose escalation to promote precision radiation oncology, where PDO can recapitulate individual patient’ tumor heterogeneity, retain characteristics of the original tumor, and predict treatment response. This review aims to introduce recent advances in the PDO technology and personalized radiotherapy, highlight the strengths and weaknesses of the PDO cancer models, and finally examine the existing RT-related PDO trials or applications to harness personalized and precision radiotherapy.