Laboratory Safety of Dupilumab in Patients Aged 6-11 Years with Severe Atopic Dermatitis: Results from a Phase III Clinical Trial.

BACKGROUND: Previous studies of dupilumab in adolescents and adults with moderate-to-severe atopic dermatitis (AD) showed no clinically meaningful adverse changes in laboratory parameters. OBJECTIVE: The aim of this study was to assess laboratory outcomes in children aged 6-11 years with severe AD in a randomized, placebo-controlled, phase III trial of dupilumab. METHODS: Children aged 6-11 years with severe AD were randomized 1:1:1 to 16 weeks of dupilumab 300 mg every 4 weeks, 100 or 200 mg every 2 weeks, or matching placebo, all with concomitant topical corticosteroids (TCS). Blood samples were collected at baseline and Weeks 4, 8, and 16; urine samples were collected at baseline and Weeks 4 and 16. RESULTS: Of 367 patients enrolled in the study, 362 were included in the safety analysis, 351 completed study treatment, and 4 withdrew due to treatment-emergent adverse events not related to laboratory abnormalities. Both dupilumab + TCS groups showed overall trends toward increases in mean blood levels of eosinophils and alkaline phosphatase, and decreases in mean blood levels of platelets, neutrophils, and lactate dehydrogenase levels, without corresponding mean changes in the placebo + TCS group. None of these changes were associated with symptoms or clinically meaningful adverse outcomes, and none led to treatment modification. No clinically significant changes or trends were observed for other measured laboratory parameters. CONCLUSION: There were no clinically meaningful adverse changes in routine laboratory parameters attributable to treatment with dupilumab + TCS. Changes in platelet counts and lactate dehydrogenase levels likely reflect reduced inflammation. These results confirm similar findings in adults and adolescents, and suggest that there is no need for routine laboratory monitoring of children aged 6-11 years treated with dupilumab + TCS for severe AD. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03345914. Does treatment with dupilumab require routine laboratory monitoring in 6- to 11-year-old children with severe atopic dermatitis? (MP4 180482 kb).

WT1 marker is not sufficient for distinguishing between melanoma and melanocytic nevi.

BACKGROUND: The heterogeneous histological features of melanoma may often overlap with melanocytic nevi. For this reason, pathologists have sought after immunohistochemistry to assist with difficult cases. Recently, Wilms' tumor 1 protein (WT1) has been suggested to differentiate between melanoma and melanocytic nevi. OBJECTIVE: Our objective was to determine whether immunohistochemistry analysis of WT1 expression is a reliable tool in differentiating cutaneous melanoma from melanocytic nevi. METHODS: Forty-five melanoma and 43 melanocytic nevi were immunostained with anti-WT1 monoclonal antibody (clone 6F-H2). RESULTS: Forty of the 45 cutaneous melanoma (89%) and 22 of the 43 melanocytic nevi (51%) stained (> 10% cells) for WT1. The highest sensitivity for WT1 was expressed by nodular melanoma (19/20), superficial spreading melanoma (8/10) and Spitz nevi (9/11). At the threshold of above 75% WT1-stained cells, the specificity for melanoma was 95% but the sensitivity was only 31%. At the threshold of 10%, the sensitivity increased to 89% but the specificity decreased to only 49%. Finally, at the threshold of 25% and 50%, the sensitivity and specificity were 71%, 61% and 64%, 77%, respectively. CONCLUSIONS: Our data suggest that melanoma is associated with increased WT1 expression. However, as a single immunostaining marker, WT1 is not sufficient for distinguishing melanoma from melanocytic nevi.

Melanoma Development and Progression Are Associated with Rad6 Upregulation and ß -Catenin Relocation to the Cell Membrane.

We have previously demonstrated that Rad6 and ß -catenin enhance each other's expression through a positive feedback loop to promote breast cancer development/progression. While ß -catenin has been implicated in melanoma pathogenesis, Rad6 function has not been investigated. Here, we examined the relationship between Rad6 and ß -catenin in melanoma development and progression. Eighty-eight cutaneous tumors, 30 nevi, 29 primary melanoma, and 29 metastatic melanomas, were immunostained with anti- ß -catenin and anti-Rad6 antibodies. Strong expression of Rad6 was observed in only 27% of nevi as compared to 100% of primary and 96% of metastatic melanomas. ß -Catenin was strongly expressed in 97% of primary and 93% of metastatic melanomas, and unlike Rad6, in 93% of nevi. None of the tumors expressed nuclear ß -catenin. ß -Catenin was exclusively localized on the cell membrane of 55% of primary, 62% of metastatic melanomas, and only 10% of nevi. Cytoplasmic ß -catenin was detected in 90% of nevi, 17% of primary, and 8% of metastatic melanoma, whereas 28% of primary and 30% of metastatic melanomas exhibited ß -catenin at both locations. These data suggest that melanoma development and progression are associated with Rad6 upregulation and membranous redistribution of ß -catenin and that ß -catenin and Rad6 play independent roles in melanoma development.

Rad6 is a Potential Early Marker of Melanoma Development.

Melanoma is the leading cause of death from skin cancer in industrialized countries. Several melanoma-related biomarkers and signaling pathways have been identified; however, their relevance to melanoma development/progression or to clinical outcome remains to be established. Aberrant activation of Wnt/ß-catenin pathway is implicated in various cancers including melanoma. We have previously demonstrated Rad6, an ubiquitin-conjugating enzyme, as an important mediator of ß-catenin stability in breast cancer cells. Similar to breast cancer, ß-catenin-activating mutations are rare in melanomas, and since ß-catenin signaling is implicated in melanoma, we examined the relationship between ß-catenin levels/activity and expression of ß-catenin transcriptional targets Rad6 and microphthalmia-associated transcription factor-M (Mitf-M) in melanoma cell models, and expression of Rad6, ß-catenin, and Melan-A in nevi and cutaneous melanoma tissue specimens. Our data show that Rad6 is only weakly expressed in normal human melanocytes but is overexpressed in melanoma lines. Unlike Mitf-M, Rad6 overexpression in melanoma lines is positively associated with high molecular weight ß-catenin protein levels and ß-catenin transcriptional activity. Double-immunofluorescence staining of Rad6 and Melan-A in melanoma tissue microarray showed that histological diagnosis of melanoma is significantly associated with Rad6/Melan-A dual positivity in the melanoma group compared to the nevi group (P=.0029). In contrast to strong ß-catenin expression in normal and tumor areas of superficial spreading malignant melanoma (SSMM), Rad6 expression is undetectable in normal areas and Rad6 expression increases coincide with increased Melan-A in the transformed regions of SSMM. These data suggest a role for Rad6 in melanoma pathogenesis and that Rad6 expression status may serve as an early marker for melanoma development.

Late type apoptosis and apoptosis free lethal effect of quercetin in human melanoma.

No satisfactory treatment is currently available for metastatic malignant melanoma. Recently, the flavonoid quercetin was suggested as a potential treatment due to its anti-tumorogenic properties. Some of these properties appeared to correspond to those published for UVB irradiation. To determine quercetin's long-term effects, type of apoptosis, and shared properties with UVB, we exposed Mel-Juso, M14, and G361 human melanoma cell-lines to a large range of quercetin or UVB doses, 20-400 microm and 25-1000 mJ/cm2 respectively. Apoptosis was measured for 4 consecutive d by flow cytometry and cell viability was studied by colony-forming assay. Quercetin decreased cell viability level in a dose-dependent manner to almost zero at 100 microm. Up to this concentration, it did not induce significant apoptosis nor did it decrease the survival-fractions below 90% during a 4 d follow-up. The data suggest that Quercetin is lethal to melanoma cells at concentrations that do not activate apoptosis during the first 4 d post-exposure and that quercetin's effects extend beyond the period of direct contact. Both quercetin and UVB induced late-type apoptosis at the upper range of the tested doses, but they do not appear to share all the pathways that they activate. Finally, this paper provides novel data showing that quercetin causes two different lethal effects on human melanoma cells, suggesting the activation of at least two different dose-depended mechanisms.