Adjuvant interferon therapy for patients at high risk for recurrent melanoma: an updated systematic review

Capn4 promotes epithelial-mesenchymal transition in human melanoma cells through activation of the Wnt/β-catenin pathway

Melanoma, as one of the most highly metastatic types of cancer, is resistant to current treatment methods, including popular targeted molecular therapy. Consequently, it is essential to develop a deeper understanding of the mechanisms involved in melanoma progression so that alternative treatments may be identified. To date, accumulating evidence supports the use of calpains, including calpain small subunit 1 (also known as Capn4 or CAPNS1), which affect cancer progression through many pathways, such as epithelial‑mesenchymal transition (EMT), the Wnt/β-catenin (β-catenin) and the nuclear factor κB (NF-κB) signaling pathways. The EMT pathway is well known as one of the most important events in tumor metastasis. The present study observed cross-talk among the EMT, β-catenin and NF-κB pathways. To identify the underlying mechanisms of Capn4 activity in melanoma cells, we determined Capn4 expression by gene chip and immunohistochemistral analyses in melanoma tissues and cells in vitro. The extent of apoptosis as determined by TUNEL assay, DAPI staining, and cleaved-caspase-3 assay was increased in human melanoma cells in which Capn4 expression had been knocked down when compared with untreated cells. Transwell assays and xenograft tumorigenicity studies were also performed to assess the effects of Capn4 on migration and invasion in vitro and tumor growth in vivo, respectively. The levels of β-catenin, vimentin, E-cadherin and N-cadherin were altered in human melanoma cells as determined by western blot analysis assay. Our study demonstrated that Capn4 is an underlying target for melanoma treatment.

Influence of genetic variants in type I interferon genes on melanoma survival and therapy

Melanoma is an immunogenic tumor; however, the efficacy of immune-therapy shows large inter-individual variation with possible influence of background genetic variation. In this study we report the influence of genetic polymorphisms in the type I interferon gene cluster on chromosome 9p22 on melanoma survival. We genotyped 625 melanoma patients recruited in an oncology center in Germany for 44 polymorphisms located on chromosome 9p22 that were informative for 299 polymorphisms and spanned 15 type I interferon genes. Our results showed associations between time to metastasis/survival and two linked (r² = 0.76) polymorphisms, rs10964859 (C>G) and rs10964862 (C>A). The rs10964859 polymorphism was located at 3′UTR and rs10964862 was 9.40 Kb towards 5′UTR of IFNW1 gene. The carriers of the variant alleles of the rs10964859 and rs10964862 polymorphisms were associated with a reduced disease-free survival. The validation of data in an independent group of 710 patients from Spain showed that the direction of the effect was similar. Stratification based on therapy showed that the adverse effect on metastasis development was statistically significant in the patients from Spain who did not receive any treatment and were homozygous for variant allele of rs10964862 (HR = 2.52, 95% CI 1.07–5.90; P = 0.03). Patients homozygous for rs10964859 (HR = 2.01, 95% CI 1.17–3.44; P = 0.01) and rs10964862 (HR 1.84, 95%CI 1.03–3.27, P = 0.04) were associated to increased risk of death following metastasis. GTCGACAA haplotype, found in 8.8% of the patients, was associated with an increased risk of death (HR 1.94, 95%CI 1.16–3.26, P = 0.01). In conclusion, our results identified genetic variants in interferon genes that influence melanoma progression and survival with modulation of effect due to treatment status.