OLDER PATIENTS AND PATIENTS WITH SEVERE ARTERIOSCLEROSIS ARE LESS LIKELY TO DEVELOP KELOIDS AND HYPERTROPHIC SCARS AFTER THORACIC MIDLINE INCISION: A SURVEY-BASED ANALYSIS OF 328 CASES

Chemotherapy affects the development of pathological scarring after general thoracic surgery in children

Globally, a great number of children have been suffering from physical dysfunction and psychological stress due to uncontrollable scar growth and a lack of effective modalities. Despite chemotherapy's established role as a primary treatment for pathological scarring in adults, its efficacy in preventing or minimizing scar formation in paediatric patients remains underexplored. This retrospective cohort study aimed to refine the relevant clinical evidence and investigate the effect of chemotherapy on pathological scars in children. In this single-centre retrospective cohort study, the data of children aged ≤18 years who underwent thoracic surgery at the Children's Hospital of Fudan University between 1 January 2018, and 31 December 2021 were assessed. The primary outcome was pathological scarring, and the secondary outcomes were subjective symptoms accompanying pathological scarring, such as pain and itching. To mitigate indication bias, analysis was performed by inverse probability weighting (IPTW) log-binomial regression models. The cohort comprised 102 children, among whom 36 received adjuvant chemotherapy perioperatively, while 66 did not. Under the IPTW model, a statistically significant difference in pathological scarring incidence was observed between the chemotherapy and non-chemotherapy groups (16.7% vs. 29.4%, p = 0.027). And the children received chemotherapy post-operatively had a lower relative risk of pathological scarring, compared with those received chemotherapy both before and after surgery (19.8% vs. 28.8%). Adjuvant chemotherapy treatment after surgery may reduce the incidence of post-operative pathological scarring in children.

Low-Frequency Ultrasound Sensitive Piezo1 Channels Regulate Keloid-Related Characteristics of Fibroblasts

Keloids are benign fibroproliferative tumors that severely diminish the quality of life due to discomfort, dysfunction, and disfigurement. Recently, ultrasound technology as a noninvasive adjuvant therapy is developed to optimize treatment protocols. However, the biophysical mechanisms have not yet been fully elucidated. Here, it is proposed that piezo-type mechanosensitive ion channel component 1 (Piezo1) plays an important role in low-frequency sonophoresis (LFS) induced mechanical transduction pathways that trigger downstream cellular signaling processes. It is demonstrated that patient-derived primary keloid fibroblasts (PKF), NIH 3T3, and HFF-1 cell migration are inhibited, and PKF apoptosis is significantly increased by LFS stimulation. And the effects of LFS is diminished by the application of GsMTx-4, the selective inhibitor of Piezo1, and the knockdown of Piezo1. More importantly, the effects of LFS can be imitated by Yoda1, an agonist of Piezo1 channels. Establishing a patient-derived xenograft keloid implantation mouse model further verified these results, as LFS significantly decreased the volume and weight of the keloids. Moreover, blocking the Piezo1 channel impaired the effectiveness of LFS treatment. These results suggest that LFS inhibits the malignant characteristics of keloids by activating the Piezo1 channel, thus providing a theoretical basis for improving the clinical treatment of keloids.