Advances in the Diagnosis and Management of Neonatal Sarcomas

RHAMM/hyaluronan inhibit β-catenin degradation, enhance downstream signaling, and facilitate fibrosarcoma cell growth

Increased hyaluronan deposition (HA) in various cancer tissues, including sarcomas, correlates with disease progression. The receptor for hyaluronic acid-mediated motility (RHAMM) expression is elevated in most human cancers. β-catenin is a critical downstream mediator of the Wnt signaling pathways, facilitating carcinogenic events characterized by deregulated cell proliferation. We previously showed that low molecular weight (LMW) HA/RHAMM/β-catenin signaling axis increases HT1080 fibrosarcoma cell growth. Here, focusing on mechanistic aspects and utilizing immunofluorescence and immunoprecipitation, we demonstrate that LMW HA treatment enhanced RHAMM intracellular localization (p ≤ 0.001) and RHAMM/β-catenin colocalization in HT1080 fibrosarcoma cells (p ≤ 0.05). Downregulating endogenous HA attenuated the association of RHAMM/β-catenin in HT1080 fibrosarcoma cells (p ≤ 0.0.01). Notably, Axin-2, the key β-catenin degradation complex component, and RHAMM were demonstrated to form a complex primarily to cell membranes, enhanced by LMW HA (p ≤ 0.01). In contrast, LMW HA attenuated the association of β-catenin and Axin-2 (p ≤ 0.05). The utilization of FH535, a Wnt signaling inhibitor, showed that LMW HA partially rescued the Wnt-dependent growth of HT1080 cells and restored the expression of Wnt/β-catenin mediators, cyclin-D1 and c-myc (p ≤ 0.05). B6FS fibrosarcoma cells with different HA metabolism do not respond to the LMW HA growth stimulus (p = NS). The present study identifies a novel LMW HA/RHAMM mechanism in a fibrosarcoma model. LMW HA regulates intracellular RHAMM expression, which acts as a scaffold protein binding β-catenin and Axin-2 at different cellular compartments to increase β-catenin expression, transcriptional activity, and fibrosarcoma growth.

Pearls and updates: cutaneous signs of systemic malignancy

PURPOSE OF REVIEW

Children with systemic malignancies can present with concomitant dermatological manifestations. Cutaneous findings can occur before, during or after diagnosis. Recognizing these features can aid in diagnosis, inform prognosis, and help determine appropriate treatment. Following a review of the literature published over the past two years, we provide an update on cutaneous signs of pediatric systemic malignancies, concentrating on; leukemia cutis, lymphoma cutis, neuroblastoma, sarcomas, Langerhans cell histiocytosis and paraneoplastic syndromes.

RECENT FINDINGS

Authors highlight the persistently heterogeneous features of cutaneous manifestations of systemic malignancy. Findings are often nonspecific, and a definitive diagnosis requires skin biopsy with immunophenotyping. Several studies describe dermoscopy features, demonstrating this as a useful tool in clinical evaluation. Genetic mutations underlying the pathogenesis of disease continue to be elucidated. Further, advances in medical treatment led to improved prognosis in many systemic malignancies, with early and aggressive treatment heralding better outcomes.

SUMMARY

Comprehensive cutaneous evaluation alongside thorough clinical history and review of systems remains of paramount importance as dermatological manifestations of systemic malignancy are notoriously variable with a shared feature of often appearing benign but persisting despite usual treatment. Urgent referral to dermatology is recommended when suspicion for any cutaneous presentation of malignancy arises.

Score for the Overall Survival Probability Scores of Fibrosarcoma Patients after Surgery: A Novel Nomogram-Based Risk Assessment System

Background

The primary purpose of this study was to determine the risk factors affecting overall survival (OS) in patients with fibrosarcoma after surgery and to develop a prognostic nomogram in these patients.

Methods

Data were collected from the Surveillance, Epidemiology, and End Results database on 439 postoperative patients with fibrosarcoma who underwent surgical resection from 2004 to 2015. Independent risk factors were identified by performing Cox regression analysis on the training set, and based on this, a prognostic nomogram was created. The accuracy of the prognostic model in terms of survival was demonstrated by the area under the curve (AUC) of the receiver operating characteristic curves. In addition, the prediction consistency and clinical value of the nomogram were validated by calibration curves and decision curve analysis.

Results

All included patients were divided into a training set (n = 308) and a validation set (n = 131). Based on univariate and multivariate analyses, we determined that age, race, grade, and historic stage were independent risk factors for overall survival after surgery in patients with fibrosarcoma. The AUC of the receiver operating characteristic curves demonstrated the high predictive accuracy of the prognostic nomogram, while the decision curve analysis revealed the high clinical application of the model. The calibration curves showed good agreement between predicted and observed survival rates.

Conclusion

We developed a new nomogram to estimate 1-year, 3-year, and 5-year OS based on the independent risk factors. The model has good discriminatory performance and calibration ability for predicting the prognosis of patients with fibrosarcoma after surgery.