A pilot study on morphology and the mechanism involved in linearly patterned programmed cell necrosis in melanoma

Accumulating data provide evidence that autophagy contributes to programmed cell death (PCD) under certain circumstances. Immunohistochemistry and real-time PCR were performed to investigate the correlation the expression of autophagy-related proteins LC3 and Atg4B and linearly patterned programmed cell necrosis (LPPCN) in melanoma. LPPCN was recently reported to be a special PCD, which is similar to neither apoptosis nor conventional necrosis commonly observed in tumoral tissues. The mechanism involved in LPPCN remains unclear. Our data showed that the expression of LC3 and Atg4B in the LPPCN-positive group was significantly higher than that in the LPPCN-negative group regarding protein and mRNA levels (p<0.05). Based on morphological observation, immunohistochemistry and real-time PCR experiments in this study, it was concluded that autophagy may play a crucial role in the process of LPP+CN in melanoma. This study provides novel insights into the mechanism that regulates LPPCN in vivo during tumor development. We speculated that LPPCN may be an early stage event in tumoral neovascularization under hypoxic-microenvironmental conditions. Accordingly, LPPCN can be considered a novel target in the process of antiangiogenesis treatment, which can be expected to obtain a better clinical outcome in the future.