The question of whether cancer stem/tumor-initiating cells (CSC/TIC) exist in human melanomas has arisen in the last few years. Here, we have used nonadherent spheres and the aldehyde dehydrogenase (ALDH) enzymatic activity to enrich for CSC/TIC in a collection of human melanomas obtained from a broad spectrum of sites and stages. We find that melanomaspheres display extensive in vitro self-renewal ability and sustain tumor growth in vivo, generating human melanoma xenografts that recapitulate the phenotypic composition of the parental tumor. Melanomaspheres express high levels of Hedgehog (HH) pathway components and of embryonic pluripotent stem cell factors SOX2, NANOG, OCT4, and KLF4. We show that human melanomas contain a subset of cells expressing high ALDH activity (ALDH high ), which is endowed with higher self-renewal and tumorigenic abilities than the ALDH low population. A good correlation between the number of ALDH high cells and sphere formation efficiency was observed. Notably, both pharmacological inhibition of HH signaling by the SMOOTHENED (SMO) antagonist cyclopamine and GLI antagonist GANT61 and stable expression of shRNA targeting either SMO or GLI1 result in a significant decrease in melanoma stem cell self-renewal in vitro and a reduction in the number of ALDH high melanoma stem cells. Finally, we show that interference with the HH-GLI pathway through lentiviralmediated silencing of SMO and GLI1 drastically diminishes tumor initiation of ALDH high melanoma stem cells. In conclusion, our data indicate an essential role of the HH-GLI1 signaling in controlling self-renewal and tumor initiation of melanoma CSC/TIC. Targeting HH-GLI1 is thus predicted to reduce the melanoma stem cell compartment.

After five years, cancer-free patients operated on for low or very low rectal cancer have a better QOL if a definitive terminal abdominal stoma was avoided.

Viraemia persistently ≤20 000-IU/mL predicts a benign clinical outcome: it was associated with transition to IC in 43% of LV-AC and to Occult HBV Infection in 20% of IC within 5-years. Nevertheless, 13.1% of individuals with low viraemia at presentation develops CHB within 1 year: 1-year HBV-DNA monitoring resulted the most accurate diagnostic approach that can be limited to at least a half of cases by the single point HBV-DNA/HBsAg quantification. The IC-diagnostic-accuracy combining HBV-DNA/total-anti-HBc/HBcrAg needs to be confirmed in further studies.

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