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SUMMARY Tyrosine kinases are critical regulators of normal cell signalling, because they control several key processes. Tyrosine kinases are specific signalling molecules playing an essential role in cell growth, survival, migration and differentiation. Their receptors are located on the cell surface, delivering signals to the nuc leus through a phosphorylation cascade. Receptor tyrosine kinases are those tyrosine kinases expressed on the cell surface that are stimulated by binding of growth factors. Tyrosine kinases are also of paramount importance in angiog enesis, and thus, in the development of tumor vascularisation. The emergence of abnormal signalling pathways due to the dysregulation of receptor tyrosine kinases is a known feature in several tumour types, and is regarded as a nega tive prognostic factor, as it alters tumor growth, proliferation and metastatic potential. Inhibition of tyrosine kinases is very important in human oncology, and it is likely that many more tyrosine kinase inhibitors will become available in the near future; and their biological activity will be enhanced as combination regimens with standard treatment modalities are explored. The use of kinase inhibitors in dogs and cats is relatively recent. There are now 2 small molecule inhibitors approved for use in veterinary medicine: Palladia (toceranib) and Masi vet/Kinavet (masitinib). Their use is approved in mast cell tumours of dogs by the Federal Drug Administration (USA). Gleevec (imatinib) is human tyrosine kinase inhibitor used in the treatment of multiple human cancers (for example chronic myelogenous leukaemia and GIST), but has been successfully used in dogs and cats as well. The authors review the current knowledge on the biology of tyrosine kinase dysfunction in human and animal cancers, and the application of specific tyrosine kinase inhibitors to veterinary cancer patients.

SUMMARY Background: Activation of the hypothalamic-pituitary-adrenal- (HPA-) axis and the sympathetic nervous system are essentially involved in the acute phase response in critically ill patients. Inadequate elevation of endogenous cortisol level and/or impaired glucocorticoid sensitivity of target cells could contribute to unfavourable disease outcome. The pathomechanism of abnormal stress response is complex. All levels of the HPA-axis could be affected, including the peripheral target tissues. Glucocorticoid resistance is a pivotal question in human medicine, but we have limited knowledge about glucocorticoid sensitivity in dogs with various inflamma tory and neoplastic disorders. Identification and treatment of patients with altered stress response are serious challenges to clinicians, even in human medicine. Objectives: Summarize the current knowledge about critical illness-related corti costeroid insufficiency (CIRCI) in dogs focusing on pathogenesis, clinical and labora tory features. Brief review of the molecular background of glucocorticoid resistance in human beings and in canine patients is also discussed. Materials and Methods: Review articles, guidelines and case reports were stud ied from different scientific online databases and journals. Main keywords used for searches: dog, critical illness, hypocortisolaemia, cortisol resistance, glucocorticoid receptor. Results and Discussion: Determining the adrenal reverse capacity is a valuable additional test beyond the basic physical and laboratory examinations in critically ill dogs, for better estimation of the disease outcome. Examination of the glucocorti coid receptor profile on target cells is necessary to understand the phenomenon of peripheral glucocorticoid resistance in critically ill canine patients.

[This corrects the article DOI: 10.3389/fvets.2024.1359426.]., (Copyright © 2024 Polton, Borrego, Clemente-Vicario, Clifford, Jagielski, Kessler, Kobayashi, Lanore, Queiroga, Rowe, Vajdovich and Bergman.)