Current status of interferon-alpha in the treatment of melanoma

Age as a key factor influencing metastasizing patterns and disease-specific survival after sentinel lymph node biopsy for cutaneous melanoma

In our study, we investigated the impact of the constitutional factor age on the clinical courses of melanoma patients with sentinel lymph node (SLN) biopsy. Descriptive statistics, Kaplan-Meier estimates, logistic regression analysis and the Cox proportional hazards model were used to study a population of 2,268 consecutive patients from three German melanoma centers. Younger age was significantly related to less advanced primary tumors. Nevertheless, patients younger than 40 years of age had a twofold risk of being SLN-positive (p < 0.000001). Of the young patients with primary melanomas with a thickness of 0.76 mm to 1.0 mm, 19.7% were SLN-positive. Using multivariate analysis, younger age, increasing Breslow thickness, ulceration and male sex were significantly related to a higher probability of SLN-metastasis. During follow-up, older patients displayed a significantly increased risk of in-transit recurrences (p = 0.000002) and lymph node recurrences (p = 0.0004). With respect to melanoma specific overall survival the patient's age was highly significant in the multivariate analysis. The unfavorable effect of being older was significant in the subgroups with positive and negative SLNs. Age remained also significant for the survival after the onset of distant metastases (p = 0.002). In conclusion, the patient's age is a strong and independent predictor of melanoma-specific survival in patients with localized melanomas, in patients with positive SLNs and after the onset of distant metastases. Younger patients have a better prognosis despite their higher probability of SLN metastasis. Older patients are less frequently SLN-positive but have a higher risk of loco-regional recurrence.

Type I IFN induced IL1-Ra expression in hepatocytes is mediated by activating STAT6 through the formation of STAT2: STAT6 heterodimer

The biological activities of type I interferons (IFNs) are mediated by their binding to a heterodimer receptor complex (IFNAR1 and IFNAR2), resulting in the activation of the JAK (JAK1 and TYK2)-STAT (1, 2, 3, 5 isotypes) signalling pathway. Although several studies have indicated that IFN-alpha and IFN-beta can activate complexes containing STAT6, the biological role of this activation is still unknown. We found that exposure of hepatoma cells (HuH7 and Hep3B) to IFN-alpha or IFN-beta led to the activation of STAT6. Activated STAT6 in turn induced the formation of STAT2: STAT6 complexes, which led to the secretion of IL-1Ra. The activation of STAT6 by type I IFN in hepatocytes was mediated by JAK1 and Tyk2. In addition, IFN-alpha or IFN-beta significantly enhanced the stimulatory effect of IL-1beta on production of IL-1Ra. The present study suggests a novel function of IFN-alpha and IFN-beta signalling in human hepatocytes. Our results provide evidence for the mechanism how IFN-alpha and IFN-beta modulate inflammatory responses through activation of STAT6 and production of secreted IL-1Ra.