Objective To investigate the expression of growth arrest and DNA damage induced protein 45 (Gadd45) A and Gadd45G in prostate cancer (PCa) tissue and their relationship with clinical pathological features and prognosis.

Methods The cancerous tissues of 80 patients with PCa admitted to our hospital between January 2020 and January 2022 were selected as the PCa group, and the paracancerous tissues were selected as the control group, which were followed up for 3 years after radical prostatectomy and divided into the recurrence group (n=31) and the non-recurrence group (n=49) according to the postoperative recurrence status. Clinical pathological characteristics data of PCa patients were collected. Western blotting was applied to detect the expression of Gadd45A and Gadd45G in two groups, and the relationship between their expression levels and the clinical pathological characteristics of patients was analyzed. Receiver operating characteristic (ROC) curve was applied to evaluate the predictive value of Gadd45A and Gadd45G for postoperative recurrence in PCa patients. Cox regression was applied to analyze the risk factors affecting postoperative recurrence in PCa patients.

Results Both Gadd45A and Gadd45G expression levels were significantly lower in the PCa group than in the control group (0.79±0.16 vs. 1.00±0.26, 0.60±0.14 vs. 0.98±0.23, P<0.05), and their low expression was associated with elevated PSA levels, increased TNM staging, and lymph node metastasis ( \chi ^2 =10.570, 9.642, 9.657, P<0.05). The expression levels of Gadd45A and Gadd45G in recurrent PCa patients were greatly lower than those in non-recurrent PCa patients (0.64±0.11 vs. 0.89±0.20, 0.47±0.10 vs. 0.68±0.16, P<0.05), and the area under the curve (AUC) of Gadd45A and Gadd45G alone and in combination in predicting postoperative recurrence in PCa patients was 0.824, 0.813, and 0.922, respectively, the combination was better than alone prediction (Z _{combination - Gadd45A}=2.384, P=0.017, Z _{combination - Gadd45G}=2.777, P=0.006). TNM staging (hazard ratio, HR)=2.038, 95% confidence interval (CI) 1.161~3.577, lymph node metastasis (HR=1.802, 95%CI 1.093~2.970), PSA levels (HR=1.736, 95%CI 1.047~2.878), and Gadd45A (HR=0.925, 95%CI 0.872~0.981) and Gadd45G (HR=0.766, 95%CI 0.610~0.962) were influencing factors for postoperative recurrence in PCa patients (P<0.05).

Conclusion In the tissues of PCa patients, the expression levels of Gadd45A and Gadd45G are reduced, and their expression levels are related to PSA level, TNM staging, and lymph node metastasis. Moreover, both have high predictive efficacy for postoperative recurrence in PCa patients and have certain clinical value.