Role of G protein-coupled receptor 1 in choriocarcinoma progression

Clinicopathological characteristics and survival outcomes for testicular choriocarcinoma: a population-based study

Background

Due to the scarcity of cases of testicular choriocarcinoma (CC), its clinicopathological characteristics and prognosis have not been well summarized. Consequently, we conducted this population-based case-control study to characterize the features of testicular CC.

Methods

The SEER database was used to extract qualified data. Dichotomous variables were compared by Pearson’s Chi-squared or Fisher exact test. Survival variables were compared by Kaplan-Meier analyses and log-rank tests. The univariable and multivariable Cox regression analyses were applied to figure out risk factors for overall survival (OS) and cancer-specific survival (CSS). Propensity score matching (PSM) was used to control confounding factors in the study.

Results

In total, 788 patients with CC and 19,571 patients with seminoma were identified. Significant differences were found between two groups in terms of age (≤30 years: 65.4% vs. 26.5%; >30 years: 34.6% vs. 73.5%; P<0.001), marital status (28.8% vs. 52.1%; P<0.001), laterality (proportion of bilateral tumors: 4.1% vs. 1.0%, P<0.001), tumors size (≤4 cm: 40.2% vs. 49.3%; >4 cm: 45.8% vs. 43.0%; P<0.001), SEER stage (localized: 43.9% vs. 79.1%; regional: 14.6% vs. 15.4%; distant: 41.0% vs. 4.7%; P<0.001), surgery (92.4% vs. 98.2%; P<0.001) and chemotherapy (65.4% vs. 19.8%; P<0.001). However, no differences were found between two groups after Propensity Score Matching (PSM). Furthermore, CC had worse outcomes than seminoma in terms of 5-year rate of OS (85.5% vs. 97.3%) and 5-year rate of CSS (86.8% vs. 98.6%). In univariable Cox hazard model, age, laterality, SEER stage (distant), surgery, chemotherapy and pathological type were independent prognostic factors for OS and CSS. However, in multivariable Cox hazard model, only age, SEER stage(distant) and surgery remained as the independent prognostic factor for OS and CSS.

Conclusions

Choriocarcinoma is exceedingly rare disease with metastases at initial diagnose and has poor survival even after treatment. Old age and advanced tumor stage indicate a poor prognosis, while surgery therapy can improve prognosis. Nevertheless, longer-term studies with larger population of patients are needed to verify their biological behavior and therapeutic efficacy.

R-spondin3 promotes the tumor growth of choriocarcinoma JEG-3 cells

R-spondin3 (RSPO3), an activator of Wnt/β-catenin signaling, plays a key role in tumorigenesis of various cancers, but its role in choriocarcinoma remains unknown. To investigate the effect of RSPO3 on the tumor growth of choriocarcinoma JEG-3 cells, the expression of RSPO3 in human term placenta was detected, and a stable RSPO3-overexpressing JEG-3 cell line was established via lentivirus-mediated transduction. The expression of biomarkers involved in tumorigenicity was detected in the RSPO3-overexpressing JEG-3 cells, and cell proliferation, invasion, migration, and apoptosis were investigated. Moreover, soft agar clonogenic assays and xenograft tumorigenicity assays were performed to assess the effect of RSPO3 on tumor growth in vitro and in vivo. The results showed that RSPO3 was widely expressed in human term placenta and overexpression of RSPO3 promoted the proliferation and inhibited the migration, invasion, and apoptosis of the JEG-3 cells. Meanwhile, RSPO3 overexpression promoted tumor growth both in vivo and in vitro. Further investigation showed that the phosphorylation levels of Akt, phosphatidylinositol 3-kinase (PI3K), and ERK as well the expression of β-catenin and proliferating cell nuclear antigen (PCNA) were increased in the RSPO3-overexpressing JEG-3 cells and tumor xenograft. Taken together, these data indicate that RSPO3 promotes the tumor growth of choriocarcinoma via Akt/PI3K/ERK signaling, which supports RSPO3 as an oncogenic driver promoting the progression of choriocarcinoma.