Deficiency of Stabilin-1 in the Context of Hepatic Melanoma Metastasis.

BACKGROUND: This study analyzed the role of Stabilin-1 on hepatic melanoma metastasis in preclinical mouse models. METHODS: In Stabilin-1-/- mice (Stab1 KO), liver colonization of B16F10 luc2 and Wt31 melanoma was investigated. The numbers, morphology, and vascularization of hepatic metastases and the hepatic microenvironment were analyzed by immunofluorescence. RESULTS: While hepatic metastasis of B16F10 luc2 or Wt31 melanoma was unaltered between Stab1 KO and wildtype (Ctrl) mice, metastases of B16F10 luc2 tended to be smaller in Stab1 KO. The endothelial differentiation of both types of liver metastases was similar in Stab1 KO and Ctrl. No differences in initial tumor cell adhesion and retention to the liver vasculature were detected in the B16F10 luc2 model. Analysis of the immune microenvironment revealed a trend towards higher levels of CD45+Gr-1+ cells in Stab1 KO as compared to Ctrl in the B16F10 luc2 model. Interestingly, significantly higher levels of POSTN were found in the matrix of hepatic metastases of Wt31, while liver metastases of B16F10 luc2 showed a trend towards increased deposition of RELN. CONCLUSIONS: Hepatic melanoma metastases show resistance to Stabilin-1 targeting approaches. This suggests that anti-Stab1 therapies should be considered with respect to the tumor entity or target organs.

Mogamulizumab Combined with Extracorporeal Photopheresis as a Novel Therapy in Erythrodermic Cutaneous T-cell Lymphoma.

BACKGROUND: Primary cutaneous T-cell lymphomas (CTCLs) are rare lymphoproliferative malignancies characterized by significant morbidity and mortality in advanced disease stages. As curative approaches apart from allogeneic stem cell transplantation are lacking, establishing new treatment options, especially combination therapies, is crucial. METHODS: This retrospective study included 11 patients with SS or MF receiving therapy with mogamulizumab in combination with ECP from four European expert centers. The response rates in the skin and blood as well as treatment use and adverse events (AE) were described. RESULTS: 8/11 patients (73%) showed an overall response (OR) in the skin. The mean mSWAT decreased from 98.2 ± 40.8 to 34.6 ± 23.8. The overall response rate (ORR) in the blood was 64% with two complete responses. During combination therapy, the mean number of Sézary cells decreased from 3365.3 × 106/L before treatment to 1268.6 × 106/L. The mean minimum known period without progress was 7.2 months in the skin and 7.6 months in the blood. The most common AEs were mogamulizumab-associated rash (MAR) (45.5%), anemia (27.3%), lymphocytopenia (27.8%), and infusion related reaction (16.7%). No AE led to treatment discontinuation. CONCLUSIONS: Our study presents the combination of mogamulizumab and ECP as an effective therapy in the blood and skin in CTCL with good tolerability, similar to mogamulizumab monotherapy.