Three tyrosine kinase inhibitors cause cardiotoxicity by inducing endoplasmic reticulum stress and inflammation in cardiomyocytes.

BACKGROUND: Tyrosine kinase inhibitors (TKIs) are anti-cancer therapeutics often prescribed for long-term treatment. Many of these treatments cause cardiotoxicity with limited cure. We aim to clarify molecular mechanisms of TKI-induced cardiotoxicity so as to find potential targets for treating the adverse cardiac complications. METHODS: Eight TKIs with different levels of cardiotoxicity reported are selected. Phenotypic and transcriptomic responses of human cardiomyocytes to TKIs at varying doses and times are profiled and analyzed. Stress responses and signaling pathways that modulate cardiotoxicity induced by three TKIs are validated in cardiomyocytes and rat hearts. RESULTS: Toxicity rank of the eight TKIs determined by measuring their effects on cell viability, contractility, and respiration is largely consistent with that derived from database or literature, indicating that human cardiomyocytes are a good cellular model for studying cardiotoxicity. When transcriptomes are measured for selected TKI treatments with different levels of toxicity in human cardiomyocytes, the data are classified into 7 clusters with mainly single-drug clusters. Drug-specific effects on the transcriptome dominate over dose-, time- or toxicity-dependent effects. Two clusters with three TKIs (afatinib, ponatinib, and sorafenib) have the top enriched pathway as the endoplasmic reticulum stress (ERS). All three TKIs induce ERS in rat primary cardiomyocytes and ponatinib activates the IRE1α-XBP1s axis downstream of ERS in the hearts of rats underwent a 7-day course of drug treatment. To look for potential triggers of ERS, we find that the three TKIs induce transient reactive oxygen species followed by lipid peroxidation. Inhibiting either PERK or IRE1α downstream of ERS blocks TKI-induced cardiac damages, represented by the induction of cardiac fetal and pro-inflammatory genes without causing more cell death. CONCLUSIONS: Our data contain rich information about phenotypic and transcriptional responses of human cardiomyocytes to eight TKIs, uncovering potential molecular mechanisms in modulating cardiotoxicity. ER stress is activated by multiple TKIs and leads to cardiotoxicity through promoting expression of pro-inflammatory factors and cardiac fetal genes. ER stress-induced inflammation is a promising therapeutic target to mitigate ponatinib- and sorafenib-induced cardiotoxicity.

Comparison and analysis of skiing injuries at ski resorts in Chongli, China and Japan.

PURPOSE: The rapid development of winter sports requires investigation on injuries in Chongli district, Zhangjiakou city, one of the ski sites of the 2022 Winter Olympics. Careful evaluation is required to observe which injuries are caused under what circumstances, and then we can make corresponding preventive measures and recommendations based on the results. METHODS: In this retrospective study, the data of injury cases at ski resorts in China (Chongli district) and Japan were analyzed to provide a reference for the ongoing injury prevention at ski resorts. We collected data on injuries at Wanlong and Fulong ski resorts in Chongli district during the 2017-2018 and 2018-2019 ski seasons. We referred to the skiing injury report issued in February 2020 of a nationwide ski safety statistical service - Japan Ski Safety Association. The causes of injury and specific injured body parts were analyzed based on the data of Chinese and Japanese ski resorts. Statistical significance has been calculated using the Chi-square test. RESULTS: During the 2019-2020 ski season in Japanese ski resorts, the number of reported injuries per 10,000 skiers was 0.93, of which 457 (17.3%) were over 50 years old, accounting for a large proportion of injuries, meanwhile in Chongli ski resort, the injury rate of skiers aged 50 and over was 7.1%. The knee joint (23.7% at Wanlong ski resort and 28.4% in Japanese ski resorts) was the most injured body part among Chongli and Japanese skiers. Among snowboarders, shoulder joint injury (17.7% in Japanese ski resorts) was the most common, and injury on hands and fingers (16.3% in Wanlong ski resorts) was the most common. Head injury rates are similar in Chongli, China and Japanese ski resorts (8.2% and 8.7%, respectively). CONCLUSION: Our analysis demonstrated that injury data recorded among young skiers was higher in Chinese ski resorts (Chongli district) than that in Japanese ski resorts, and elderly skiers made up a larger proportion of skiing injuries in Japanese resorts. Thus, according to our research, the protection of knee joints, shoulder joints, and hands and fingers should be taken seriously. It should pay attention to the teaching of ski poles (for finger protection), and use protective devices such as knee pads, helmets, etc.