Recurrence Features and Factors influencing Post-relapse Survival in Early-stage Endometrial Cancer after Adjuvant Radiotherapy

Effect of time interval between surgery and the initiation of adjuvant therapy on the oncologic outcomes of early-stage endometrial cancer

OBJECTIVE

To identify the impact of time interval between surgery and initial adjuvant radiotherapy on oncologic outcomes in early-stage endometrial cancer.

METHODS

This retrospective cohort study included patients with stage I/II endometrial cancer who underwent surgical staging and adjuvant therapy at Songklanagarind Hospital from January 1, 2007, to December 31, 2017. Patients were categorized into two groups: TI <6 weeks and TI ≥6 weeks. The effects of TI and clinicopathological factors on recurrence-free survival (RFS) and overall survival (OS) were analyzed using Cox proportional-hazards regression.

RESULTS

In total, 177 patients were enrolled, with 52% receiving adjuvant radiotherapy at <6 weeks (overall median TI 5.7 weeks). The recurrence and death rates were 13% and 10.2%, respectively. The median follow-up time was 46.6 months. The overall 3-year RFS and OS rates were 88.2% and 85.2%, respectively. The TI significantly affected the 3-year RFS (94.4% vs 81.2%; P = 0.008) and 3-year OS (95.5% vs 83.2%; P = 0.012) in patients with TI <6 and ≥6 weeks, respectively. In multivariate analysis, the depth of myometrial invasion (MI), presence of lymphovascular space invasion, and TI were independent prognostic factors for both RFS and OS. Delaying the TI (≥6 weeks) was significantly associated with a worse RFS (hazard ratio [HR] 3.70; 95% confidence interval [CI]: 1.34-10.22; P = 0.012) and an inferior OS (HR 3.80; 95% CI: 1.23-11.69; P = 0.02).

CONCLUSION

A delay in the TI between surgery and the initiation of adjuvant radiotherapy of ≥6 weeks negatively affected the oncologic outcomes in early-stage endometrial cancer.

CircCCL22 Regulates CDC25A via Sponging miR-543 and Promotes Proliferation and Metastasis in Endometrial Cancer

Endometrial cancer (EC) is the most common gynecological tumor. Circular RNAs are a novel type of non-coding RNA that have important regulatory functions, particularly in the pathogenic progression of cancer. In this study, we investigated the function of circCCL22, and elucidated its molecular mechanism in EC progresssion. The expression of circCCL22, miR-543 and CDC25A in EC tissues and cells were determined by qRT-PCR and western blot. Cell counting kit-8, 5-ethynyl-2'-deoxyuridine, wound healing and transwell assays were executed to assess the cell viability, proliferation, migration and invasion. Dual-luciferase report assay was utilized to investigate the interaction of miR-543 with circCCL22 and CDC25A. The role of circCCL22 in EC in vivo was investigated by xenograft assay. CircCCL22 was notably upregulated in EC tissues and cells. Functionally, circCCL22 knockdown suppressed EC cell proliferation, migration and invasion in vitro, and inhibited tumor growth in vivo. Mechanistically, circCCL22 acted as "miR-543 sponges" to regulate its targeted gene CDC25A expression in EC cells. The inhibiting effect induced by circCCL22 knockdown on EC cell proliferation, migration and invasion was greatly reversed by miR-543 inhibition or CDC25A overexpression. Our results revealed that circCCL22 regulated EC progression through targeting miR-543/CDC25A axis, and it could be a novel therapeutic target of EC.