[Expression of RACK1 and EGP40 in oral squamous cell carcinoma and its correlation with clinicopathological features and prognosis].

PURPOSE： To investigate the expression of tissue-active protein kinase C receptor 1 (RACK1) and epithelin glycoprotein 40 (EGP40) in oral squamous cell carcinoma (OSCC) and their relationship with clinicopathological features and prognosis.
Methods: A total of 103 patients with OSCC who were admitted to Shangrao People's Hospital from January 2016 to February 2019 were prospectively selected as the research subjects. All patients underwent radical resection of OSCC and were followed up for 3 years. Immunohistochemistry was used to detect the positive expression levels of RACK1 and EGP40 in cancer tissues and adjacent tissues. The positive expression of RACK1 and EGP40 in cancer tissues and adjacent tissues were compared. The relationship between the positive expression level of RACK1 and EGP40 in cancer tissues of OSCC patients and clinicopathological parameters was analyzed. Factors affecting postoperative recurrence and metastasis in OSCC patients were analyzed. The relationship between the expression of RACK1 and EGP40 in cancer tissues and postoperative disease-free survival of OSCC patients was analyzed. SPSS 18.0 software package was used for statistical analysis of the data.
Results: The positive expression rate of RACK1 and EGP40 in cancer tissues was significantly higher than those in adjacent tissues (P＜0.05). The positive expression rate of RACK1 and EGP40 in cancer tissues of OSCC patients with poorly differentiated, stage III, cervical lymph node metastasis, and infiltrating vessels was significantly higher than that in patients with moderate and high differentiation, stage II, no cervical lymph node metastasis, and no infiltrating vessels(P＜0.05). The positive expression rate of RACK1 in cancer tissue of OSCC patients in T3 stage was significantly higher than that in T2 stage(P＜0.05). Cox multivariate regression analysis showed pathological grade (RR=6.290, 95%CI: 2.588-15.287), cervical lymph node metastasis(RR=5.995, 95%CI: 2.467-14.571), RACK1 positive rate (RR=4.495, 95%CI: 1.850-10.925) and EGP40 positive rate (RR=4.559, 95%CI: 1.876-11.079) were factors affecting the recurrence and metastasis of OSCC patients after surgery(P＜0.05). The disease-free survival curve of patients with negative expression of RACK1 was significantly better than that of patients with positive expression (P＜0.05). The disease-free survival curve of patients with negative expression of EGP40 was significantly better than that of patients with positive expression (P＜0.05).
Conclusions: The expression of RACK1 and EGP40 in cancer tissues of OSCC patients is related to clinicopathological parameters and prognosis. Patients with positive expression of RACK1 and EGP40 have a high risk of recurrence and metastasis after surgery.