Expression of fibroblast growth factor receptor substrate 2 (FRS2) in primary retroperitoneal liposarcoma and its clinical implications.

OBJECTIVE: The aim of this study was to investigate the expression level of fibroblast growth factor receptor substrate 2 (FRS2) in tissues of patients with primary retroperitoneal liposarcoma (PRPLS) and its correlation with recurrence and prognosis. PATIENTS AND METHODS: The pathological specimens, medical records, and follow-up information of patients with PRPLS who underwent radical surgery for the first time in our hospital from January 2013 to December 2016 were retrospectively analyzed. FRS2 protein expression in tissues was determined by immunohistochemistry staining, and the FRS2 protein positive rates in patients with different clinicopathological features were compared. Factors influencing patients' recurrence and survival were determined using the multivariate Cox stepwise regression model. RESULTS: This research enrolled 87 patients with PRPLS, with the number of cases presenting FRS2 protein positive rate and positive rate in pathological tissues accounting for 62.07% (54/87) and 37.93% (33/87), respectively. The positive expression of FRS2 protein varied markedly among patients with different pathological types, FNCC, LCC grade, number of tumors, positive margin, and recurrence and metastasis (with vs. without) (all p<0.05). The 87 patients were followed up for 3.5-102 months (median, 27.5 months), with a postoperative 5-year overall disease-free survival (DFS) rate of 17.24% [median progression-free survival (PFS): 24.7 months] and a 5-year overall survival (OS) rate of 44.83% (median OS: 47.3 months). Kaplan-Meier survival curves revealed significantly shorter PFS and OS in patients with positive FRS2 protein expression vs. those with negative FRS2 protein expression (χ2=6.396, 5.032, p<0.05). According to the univariate analysis, the 5-year overall DFS rate varied significantly among patients with different pathological types, Fédération Nationale des Centres De Lutte Contre le Cancer (FNCLCC) grades, number of tumors, positive margin, and FRS2 protein expression (all p<0.05). Pathological type, FNCLCC grading, tumor number, recurrence and metastasis, positive margin, and FRS2 protein expression were significantly correlated with the 5-year OS rate of patients (all p<0.05). Furthermore, pathological type, FNCLCC grading, multiple tumors, positive margin, and FRS2 protein expression were identified by multivariate Cox regression analysis to be independent factors that affected patients' 5-year DFS and OS rates (all p<0.05), and that relapsed and metastasized patients had a 4.586-fold risk of death than those without recurrence and metastasis. CONCLUSIONS: FRS2 shows a high positive rate in the tissues of PRPLS patients and is significantly related to the prognostic recurrence and survival of patients, with potential value in judging the prognosis of patients.

[Treatment and prognosis of retroperitoneal liposarcoma with multiple primary tumor].

Objective: To investigate the multiple origin of retroperitoneal liposarcoma and its postoperative prognosis. Methods: A total of 49 retroperitoneal liposarcoma patients underwent total (ipsilateral) retroperitoneal lipectomy in our center from May 2017 to December 2019 were recruited. Clinical data and the follow-up information were reviewed and the origin and prognosis were analyzed. Results: A total of 15 patients were pathologically diagnosed as multiple primary cancer (MPC), the incidence rate of retroperitoneal liposarcoma with MPC was 30.6% (15/49), while other 34 cases was non-MPC. The postoperative recurrence rates of patients with high differentiation and de-differentiation retroperitoneal liposarcoma were 31.8% and 44.4%, without significant difference (P>0.05). The postoperative recurrence rates of MPC and non-MPC were 40.0% and 38.2%, without significant difference (P>0.05). Five cases died within the follow-up. Conclusion: Retroperitoneal liposarcoma might origin form MPC, and total (ipsilateral) retroperitoneal lipectomy is recommended to reduce the recurrence rate.

Ifenprodil and ethanol enhance NMDA receptor-dependent long-term depression.

Long-term alterations in synaptic transmission are thought to underlie various types of alcohol-related brain disorders. While ethanol effects on synaptic potentiation are well documented, ethanol effects on synaptic depression have not been addressed. Herein, we performed experiments to assess the role of ethanol on long-term depression (LTD) formation. In rat hippocampal slices, prolonged low-frequency stimulation (LFS) of CA1 Schaffer collaterals (1 Hz for 7 min) induced saturable, long-lasting, reversible N-methyl-D-aspartate (NMDA) receptor-dependent LTD of stimulus-evoked dendritic population excitatory postsynaptic potentials. This depression (-26% LTD amplitude) was observed in young rats (12-20 days old), but not adult rats (28-35 days old). Induction of LTD was blocked (-3% LTD amplitude) when the LFS was delivered in the presence of the NMDA receptor antagonist D-2-amino-5-phosphonovaleric acid. When the conditioning LFS was delivered in the presence of ethanol, there was a significant enhancement in the induction of NMDA receptor-dependent LTD versus control LTD (-36% LTD amplitude). Ifenprodil, an N-methyl-D-aspartate receptor subunit 2B (NR2B)-selective antagonist, also significantly facilitated the induction of LTD (-40% LTD amplitude). Consistent with this result, ifenprodil did not affect the NMDA receptor-dependent component of the baseline synaptic response, whereas D-2-amino-5-phosphonovaleric acid caused significant depression of the NMDA component. These data indicate that whereas ethanol is known to inhibit NMDA receptor function in a variety of systems, it significantly enhances the induction of NMDA receptor-dependent LTD. Furthermore, since ifenprodil is known to select for ethanol-sensitive subtypes of NR2B-NMDA receptors, these data also suggest that NR2B-containing NMDA receptor subpopulations do not contribute to LTD, but instead may actually play inhibitory roles in LTD induction.