Comparative genomics of high grade neuroendocrine carcinoma of the cervix

PLoS One. 2020 Jun 16;15(6):e0234505. doi: 10.1371/journal.pone.0234505. eCollection 2020.

Abstract

In order to improve treatment selection for high grade neuroendocrine carcinomas of the cervix (NECC), we performed a comparative genomic analysis between this rare tumor type and other cervical cancer types, as well as extra-cervical neuroendocrine small cell carcinomas of the lung and bladder. We performed whole exome sequencing on fresh-frozen tissue from 15 NECCs and matched normal tissue. We then identified mutations and copy number variants using standard analysis pipelines. Published mutation tables from cervical cancers and extra-cervical small cell carcinomas were used for comparative analysis. Descriptive statistical methods were used and a two-sided threshold of P < .05 was used for significance. In the NECC cohort, we detected a median of 1.7 somatic mutations per megabase (range 1.0-20.9). PIK3CA p.E545K mutations were the most frequency observed oncogenic mutation (4/15 tumors, 27%). Activating MAPK pathway mutations in KRAS (p.G12D) and GNAS (p.R201C) co-occurred in two tumors (13%). In total we identified PI3-kinase or MAPK pathway activating mutations in 67% of NECC. When compared to NECC, lung and bladder small cell carcinomas exhibited a statistically significant higher rate of coding mutations (P < .001 for lung; P = .001 for bladder). Mutation of TP53 was uncommon in NECC (13%) and was more frequent in both lung (103 of 110 tumors [94%], P < .001) and bladder (18 of 19 tumors [95%], P < .001) small cell carcinoma. These comparative genomics data suggest that NECC may be genetically more similar to common cervical cancer subtypes than to extra-cervical small cell neuroendocrine carcinomas of the lung and bladder. These results may have implications for the selection of cytotoxic and targeted therapy regimens for this rare disease.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Carcinoma, Neuroendocrine / genetics*
  • Carcinoma, Neuroendocrine / pathology
  • Cervix Uteri / metabolism
  • Cervix Uteri / pathology
  • Chromogranins / genetics
  • Class I Phosphatidylinositol 3-Kinases / genetics
  • Cohort Studies
  • DNA Copy Number Variations / genetics*
  • Exome Sequencing
  • Female
  • GTP-Binding Protein alpha Subunits, Gs / genetics
  • Genomics*
  • Humans
  • Middle Aged
  • Mutation / genetics
  • Proto-Oncogene Proteins p21(ras) / genetics
  • Tumor Suppressor Protein p53
  • Uterine Cervical Neoplasms / genetics*
  • Uterine Cervical Neoplasms / pathology

Substances

  • Chromogranins
  • KRAS protein, human
  • TP53 protein, human
  • Tumor Suppressor Protein p53
  • Class I Phosphatidylinositol 3-Kinases
  • PIK3CA protein, human
  • GNAS protein, human
  • GTP-Binding Protein alpha Subunits, Gs
  • Proto-Oncogene Proteins p21(ras)