Search

Abstract Background To reveal the function of protein tyrosine phosphatase‐L1 (PTPL1) in lung adenocarcinoma. Methods Lung cancer cell lines were transfected with short hairpin RNA against PTPL1 (shPTPL1 group) or negative control (shmock group). Quantitative real‐time polymerase chain reaction (qRT‐PCR) and western blotting were used to verify the transfection efficacy. Cell proliferation was analyzed by ethynyldeoxyuridine (EdU), Cell counting kit 8 (CCK8), and colony formation assay after PTPL1 or PTPL1 and yes‐associated protein (YAP1) knockdown. The effect of PTPL1 on tumor growth was examined in a xenograft lung cancer model. Results PTPL1 was downregulated in various types of lung cancer cell lines. The EdU, CCK8, colony formation assays and investigation using a xenograft lung cancer model indicated that PTPL1 knockdown increased the proliferation of lung cancer cells. Mechanistically, PTPL1 knockdown induced the activation of the Proto‐oncogene tyrosine‐protein kinase SRC (Src)/Extracellular regulated MAP kinase (ERK) pathway and thereby promoted yes‐associated protein (YAP1) nuclear translocation and activation. Conclusions In our study, PTPL1 played a crucial suppressive role in the pathogenesis of lung cancer potentially through counteracting the Src/ERK/YAP1 pathway.

Abstract Schwannomas are homogeneous tumors of schwann cells and occur at peripheral and cranial nerves on the upper limbs, the head and neck area. Rarely, a bronchial schwannoma may appear in the lung and be misdiagnosed as lung neoplasms. Here, we report a 56‐year old woman with a 5.8 × 7.0 × 2.8 cm lesion in her right upper lobe bronchus. The lesion had a maximum standardized uptake value (SUVmax) of 8.5 by 18‐fluorodeoxyglucose positron emission tomography (FDG‐PET). Bronchoscopy showed a mass obstructing the bronchus that bled easily. Despite repeated biopsies, a lung malignancy could not be excluded, and surgical resection was subsequently performed. Pathological examination demonstrated a primary bronchial schwannoma that was positive for molecular markers S‐100 and SOX‐10, negative for immune checkpoint marker PD‐1/PD‐L1 but also demonstrated certain uncommon pathological features. This case highlights the heterogeneity of bronchial masses and the diagnostic challenge for differentiating benign and malignant tumors in the thorax. Key points Rare bronchial schwannoma mimics lung malignancy and poses a diagnostic challenge. This case of bronchial schwannoma, unlike peripheral schwannoma, lacks PD‐L1. Pathological features indicate autonomic nerve origin for pulmonary schwannomas.