Purpose: Drug resistance is one of the main causes of chemotherapy failure in patients with small cell lung cancer (SCLC), and extensive biological studies into chemotherapy drug resistance are required. Materials and Methods: In this study, we performed lncRNA microarray, in vitro functional assays, in vivo models and cDNA microarray to evaluate the impact of lncRNA in SCLC chemoresistance. Results: The results showed that KCNQ1OT1 expression was upregulated in SCLC tissues and was a poor prognostic factor for patients with SCLC. Knockdown of KCNQ1OT1 inhibited cell proliferation, migration, chemoresistance and promoted apoptosis of SCLC cells. Mechanistic investigation showed that KCNQ1OT1 can activate transforming growth factor-β1 mediated epithelial-to-mesenchymal transition in SCLC cells. Conclusion Taken together, our study revealed the role of KCNQ1OT1 in the progression and chemoresistance of SCLC, and suggested KCNQ1OT1 as a potential diagnostic and prognostic biomarker in SCLC clinical management.

Objective:To investigate the feasibility of conducting active surveillance (AS) for low risk papillary thyroid microcarcinoma (PTMC) in China and to examine the factors in association with disease progression during AS.Methods:This study was a prospective observational research conducted from Jun. 2018 to Aug. 2022 at Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine. Seventy-three patients with cytologically confirmed low-risk PTMC were enrolled in this study. They were followed up by ultrasonography, and the observed nodules were re-assessed whether or not to have disease progression. Disease progression was defined as having nodule enlarged more than 3 mm in any of diameters measured on ultrasound, or/and presence of suspicious lymph node metastasis.Results:The median follow-up time was 33 months. At the time of last follow-up, 16 cases (21.9%) exhibited disease progression, including 9 cases (12.3%) with suspicious lymph nodes detected by ultrasound, and 8 cases (11.0%) with lesion enlargement; one case (1.3%) exhibited both situations. The univariate chi-square analysis revealed that young patients (≤45 years old, P=0.041), presence of microcalcifications ( P=0.032), initial larger nodule (diameter greater than 7 mm, P=0.003), and elevated thyroid autoantibody levels ( P=0.008) were associated with disease progression. Multiple regression analysis showed elevated thyroid autoantibodies ( OR=4.311, P=0.030) and initial larger nodule ( OR=6.196, P=0.034) were independent risk factors for PTMC progression,respectively. Conclusions:AS for low-risk PTMC is a feasible and effective. During the observation, ultrasound can reveal suspicious lymph nodes and nodule enlargement, which are crucial indicators for assessing disease progression. Patients with initially larger nodule size and elevated thyroid autoantibody level are more likely to exhibit disease progression and should receive closer attention.