This study reviews how ionizing radiation (IR) induces alternative splicing (AS) in non-tumor and tumor cells under both ex vivo and in vivo irradiation conditions. The relevance and limitations of IR-induced AS in identifying potential biomarkers are highlighted for two main applications: biodosimetry and radiotherapy. Radiation promotes alterations in AS, which may differentially affect the response in both tumor and non-tumor cells. This response can occur in genes that change their overall expression as well as in those that remain unaltered in response to IR. Although cis-regulators modulate AS, trans-regulators like splicing factors are more involved in the IR response. Variants of key genes involved in the DNA damage response (DDR) are regulated in non-tumor cells while they are often deregulated in tumor cells favoring radioresistance. Identifying IR-induced AS variants could enhance the sensitivity of biodosimeters for dose estimation and biomarkers for radiosensitivity, offering potential strategies to personalize radiotherapy and improve outcomes. New and advanced sequencing technologies will allow variant identification important for the field of radiobiological research.
13 April 2023 in Journal of Endocrinological Investigation
Thyroid carcinoma (TC) is the most common endocrine neoplasia, with its incidence increasing in the last 40 years worldwide. The determination of genetic and/or protein markers for thyroid carcinoma could increase diagnostic precision. Accumulated evidence shows that Protein kinase C alpha (PKCα) contributes to tumorigenesis and therapy resistance in cancer. However, the role of PKCα in TC remains poorly studied. Our group and others have demonstrated that PKCs can mediate the proliferative effects of thyroid hormones (THs) through their membrane receptor, the integrin αvβ3, in several cancer types. We found that PKCα is overexpressed in TC cell lines, and it also appeared as the predominant expressed isoform in public databases of TC patients. PKCα-depleted cells significantly reduced THs-induced proliferation, mediated by the integrin αvβ3 receptor, through AKT and Erk activation. In databases of TC patients, higher PKCα expression was associated with lower overall survival. Further analyses showed a positive correlation between PKCα and genes from the MAPK and PI3K-Akt pathways. Finally, immunohistochemical analysis showed abnormal upregulation of PKCα in human thyroid tumors. Our findings establish a potential role for PKCα in the control of hormone-induced proliferation that can be explored as a therapeutic and/or diagnostic target for TC.
Background: Boron neutron capture therapy (BNCT) is a binary modality based on the nuclear reaction 10B (n, α) lithium-7 (7Li) that has been used to treat a variety of tumors, among these, cutaneous melanoma (CM). In previous boron biodistribution studies in agreement with the personalized oncology, we have demonstrated that boronophenylalanine (BPA) uptake can be correlated with the tumoral temperature and viability. The main aim of these studies was to evaluate the relationship between tumoral temperature and the response to the complete BNCT. Methods: Nude mice were implanted with human melanoma cells (Mel J) and divided into different groups (Control, NCT, BNCT I and BNCT II) and irradiated with the thermal neutron beam from RA-6 (4.96×108/cm2/sec) during 37 and 55 minutes respectively. Tumor and body temperatures were measured by Static Infrared Imaging (SIRI), and it was performed the following up of the animals. Results: Tumor growth showed a complete growth inhibition during the first 20 days after treatment in both BNCT groups (BNCT I and BNCT II vs. Control P<0.001). Considering the analogy between the Fourier’s Law of Heat Conduction and the Ohm’s law of Electrical Conduction, the quantity (T_tum-T_inf)/(T_body-T_tum) was analyzed as a function of Vf/Vi (Final volume/Initial volume) ratio. A tendency to higher values of the temperature’s ratios, was observed with respect to the degree of tumor control (BNCT I with a R2 of 0.3527, BNCTII with a R2 of 0.3327) in agreement with previous boron biodistribution studies. The histology and immunohistochemical studies showed larger areas of necrosis and picnotic regions and a significant decrease of the Ki-67 antibody labeling in the BNCT II group evidencing important tumor damage. Conclusions: tumoral characteristics, especially the temperature, could be used to plan a personalized treatment for each patient. As values of correlation between temperature and tumoral response showed to be weak, we considered to explore a new model of three dimension for heat transport process.