Is surgery a risk factor for contralateral recurrence pneumothorax in adolescent with primary spontaneous pneumothorax?

OBJECTIVES: Controversy exists regarding the justification of primary surgery in primary spontaneous pneumothorax, and surgery is not free from recurrence. We hypothesized that surgery is a risk factor for contralateral recurrence pneumothorax in adolescent. METHODS: We performed a retrospective cohort study of 163 adolescent with pneumothorax who were treated conservatively with chest tube (n = 100) or chest tube followed by video-assisted thoracoscopic surgery (n = 63) from January 2009 through December 2017. RESULTS: Ipsilateral recurrence was significantly more common following conservative treatment than surgical treatment (25.0 vs. 3.2%, P < 0.001), while contralateral recurrence was more common in the surgical group than in the conservative group (15.9 vs. 6.0%, P = 0.039). The rates of second episode pneumothorax did not significantly differ between the two treatment groups (P = 0.092). Univariate analysis identified that patients who were treated conservatively had greater risk of ipsilateral recurrence (P = 0.002), while those who proceeded to surgery had greater risk of contralateral recurrence (P = 0.046). No predictors for second episode pneumothorax were found. CONCLUSION: To avoid over treatment, we recommend that conservative treatment should be the superior option and CT scan should not be a routine examination in adolescent with their first episode of PSP.

MicroRNA­21 regulates the biological behavior of esophageal squamous cell carcinoma by targeting RASA1.

MicroRNA­21 (miR­21) has been revealed to play a crucial role in regulating the biological behavior, including proliferation, migration, invasion and metastasis in certain cancers. However, its role in esophageal squamous cell carcinoma (ESCC) has yet to be elucidated. Based on the data of GSE13937 downloaded from Gene Expression Omnibus (GEO) database, miR­21 was revealed to be one of the top 20 differentially expressed (DE) miRNAs screened using the Morpheus online tool. RAS p21 protein activator 1 (RASA1) was predicted as the target gene of miR­21 using the predicting software and was combined with miR­21 using the luciferase reporter assay. Its relative expression was significantly decreased, however, miR­21 was increased in the tumor tissues compared to the normal adjacent tissues in patients with ESCC as determined by quantitative polymerase chain reaction (q­PCR). Furthermore, overexpression of miR­21 (mimic) could significantly decrease the gene level of RASA1. Conversely, downregulation of miR­21 (inhibitor) significantly increased the gene level of RASA1, while downregulation of RASA1 (siRASA1) markedly increased the gene expression of miR­21. Notably, the expression of Snail and vimentin were significantly increased by upregulation of miR­21 and downregulation of RASA1. Transwell results revealed that miR­21 and RASA1 regulated proliferation, migration and invasion in ESCC cells. In an in vivo model, miR­21 inhibitor (antagomir) could inhibit tumor growth. In conclusion, miR­21 regulated cell proliferation, migration, invasion and tumor growth of ESCC by directly targeting RASA1, which may have been achieved via regulation of Snail and vimentin. Anti­miR­21 revealed an antitumor effect. Thus, it may be considered as a possible target for ESCC therapy.