In vivo tumor growth assay

BALB/c mice (five weeks; Chinese Academy of Medical Sciences, Beijing, China) were used to perform the in vivo tumor growth assay to explore the influence of circ_0072088, miR‐377‐5p and NOVA2 on the growth of NSCLC tumors in vivo. Animal manipulates were approved by the Animal Research Committee of Affiliated Hospital of Shandong University of Traditional Chinese Medicine. A‐549 cells stably expressing sh‐NC or sh‐hsa_circ_0072088 were harvested and adjusted to the concentration of 2 × 10⁶ cells/100 μL PBS. Then, 100 μL cell suspension was subcutaneously injected into the left flank of nude mice. The tumor volume was recorded every week using the formula of length × width² × 0.5. The mice were sacrificed after five weeks by injection, and the tumors were dissected and weighed. The abundance of hsa_circ_0072088, miR‐377‐5p, PCNA and NOVA2 in tumor specimens was detected by qRT‐PCR or western blot assay.