Abstract: Objective To investigate the expression of PROM2,RALY and Rab15 in non-small cell lung cancer (NSCLC) and the predictive value for the development of bone metastasis in NSCLC.Methods One hundred and thirty four patients diagnosed with NSCLC in our hospital from Mar 2016 to Feb 2022 were retrospectively analyzed.Patients were divided into bone metastasis (BM) and non-bone metastasis (NBM) groups based on the occurrence of bone metastasis during follow-up.Immunohistochemistry was used to detect the expression of PROM2,RALY,and Rab15 in cancer tissues.The relationship between the expression of these markers and bone metastasis was analyzed,and Cox regression was used to identify risk factors for bone metastasis in NSCLC patients.Results During the follow-up period,43 patients with NSCLC developed bone metastases.Patients with bone metastases had higher age,BMI,percentage of adenocarcinoma,and positive expression of PROM2,RALY and Rab15 than those without bone metastases (P<0.05).Multifactorial Cox analysis showed that age,type of pathology,ECOG, and the positive PROM2 expression were significant risk factors for bone metastases in NSCLC patients(P<0.05).Among patients with bone metastases,those with positive PROM2 expression had a shorter median bone metastasis-free survival time compared to PROM2-negative patients (P<0.05).Conclusion PROM2 positive expression is an independent risk factor for bone metastasis in NSCLC patients,and is closely related to their prognosis.

Key words: PROM2;non-small cell lung cancer;bone metastasis