Gene-Specific Intron Retention Serves as Molecular Signature that Distinguishes Melanoma from Non-Melanoma Cancer Cells in Greek Patients

Int J Mol Sci. 2019 Feb 21;20(4):937. doi: 10.3390/ijms20040937.


Background: Skin cancer represents the most common human malignancy, and it includes BCC, SCC, and melanoma. Since melanoma is one of the most aggressive types of cancer, we have herein attempted to develop a gene-specific intron retention signature that can distinguish BCC and SCC from melanoma biopsy tumors.

Methods: Intron retention events were examined through RT-sqPCR protocols, using total RNA preparations derived from BCC, SCC, and melanoma Greek biopsy specimens. Intron-hosted miRNA species and their target transcripts were predicted via the miRbase and miRDB bioinformatics platforms, respectively. Ιntronic ORFs were recognized through the ORF Finder application. Generation and visualization of protein interactomes were achieved by the IntAct and Cytoscape softwares, while tertiary protein structures were produced by using the I-TASSER online server.

Results: c-MYC and Sestrin-1 genes proved to undergo intron retention specifically in melanoma. Interaction maps of proteins encoded by genes being potentially targeted by retained intron-accommodated miRNAs were generated and SRPX2 was additionally delivered to our melanoma-specific signature. Novel ORFs were identified in MCT4 and Sestrin-1 introns, with potentially critical roles in melanoma development.

Conclusions: The property of c-MYC, Sestrin-1, and SRPX2 genes to retain specific introns could be clinically used to molecularly differentiate non-melanoma from melanoma tumors.

Keywords: BCC; SCC; cancer; intron; melanoma; splicing; transcription.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Diagnosis, Differential
  • Female
  • Genetic Testing / methods*
  • Heat-Shock Proteins / genetics
  • Heat-Shock Proteins / metabolism
  • Humans
  • Introns
  • Male
  • Melanoma / genetics*
  • Melanoma / pathology
  • Membrane Proteins
  • Middle Aged
  • Monocarboxylic Acid Transporters / genetics
  • Monocarboxylic Acid Transporters / metabolism
  • Muscle Proteins / genetics
  • Muscle Proteins / metabolism
  • Neoplasm Proteins
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism
  • Proto-Oncogene Proteins c-myc / genetics
  • Proto-Oncogene Proteins c-myc / metabolism
  • RNA Splicing*
  • Skin Neoplasms / genetics*
  • Skin Neoplasms / pathology


  • Heat-Shock Proteins
  • Membrane Proteins
  • Monocarboxylic Acid Transporters
  • Muscle Proteins
  • Neoplasm Proteins
  • Nerve Tissue Proteins
  • Proto-Oncogene Proteins c-myc
  • SESN1 protein, human
  • SLC16A4 protein, human
  • SRPX2 protein, human