Objective: To investigate DACH1 protein expression in lung cancer tissue and matched paracancerous tissue and explore its effect on proliferation, invasion, and apoptosis in human lung adenocarcinoma cells (HLACs). Methods: Tumor tissue and matched paracancerous tissue were collected from 46 patients with pathologically diagnosed lung cancer. RT-PCR was performed to detect DACH1 mRNA expression and immunohistochemistry to measured DACH1 protein expression. To determine the effect of DACH1 on lung cancer behavior, small interfering RNA (siRNA) was used to silence DACH1 expression in A549 cells. The impact on the proliferation of tumor cells was then observed by MTT assay, changes in the invasion of tumor cells were identified using transwell chamber assay, and the effects on apoptosis in the cell line were detected using flow cytometry. Results: The expression of DACH1 mRNA and DACH1 protein was significantly decreased in lung cancer tissue versus matched paracancerous control tissue. The silencing of DACH1 expression in A549 cells significantly enhanced cell proliferation, significantly increased cell invasion, and significantly reduced spontaneous apoptosis. Conclusion: DACH1 is downregulated in lung adenocarcinoma tissue. In vitro assessment shows that DACH1 functions as a tumor suppressor, suggesting its potential use as a new target for lung cancer treatment.

Intrathoracic meningocele associated with neurofibromatosis type 1 is quite rare. We report the case of a Chinese women with a 20-day history of right-sided chest pain and sense of pressure on the chest. Computed tomography and magnetic resonance imaging indicated a homogeneous thin-walled cystic mass in the right rear mediastinum, ranging from the 1st to 5th thoracic segments. Surgery was performed to removal the meningomyelocele pouches and shunt the cyst to the subarachnoid region.

Introduction: Langerhans cell histiocytosis (LCH) is a rare neoplastic hyperplasia with an unknown etiology. It is clinically rare for patients with solitary rib lesion and pathological fracture; moreover, its diagnosis and treatment are quite difficult. The purpose of this study is to present a case for the pathogenesis, clinical features, imaging, and treatment of this disease. Case presentation: A 52-year-old female patient complained of left chest pain for one week. CT showed a fracture in the left 5th rib. The rib tumor was then resected and the surrounding muscles and soft tissues were accordingly resected. The patient was diagnosed with pathological rib fracture, and the patient was pathologically diagnosed with LCH. After surgery, no local recurrence or distant metastasis was reported during the two-year follow-up. Conclusions: LCH should be treated by observation, chemotherapy, radiotherapy, or surgery, or using a combination of several methods. Moreover, primary tumor should be considered when rib fracture without trauma and tumor metastasis.