Transcriptome Analysis Reveals HgCl2 Induces Apoptotic Cell Death in Human Lung Carcinoma H1299 Cells through Caspase-3-Independent Pathway

Int J Mol Sci. 2021 Feb 18;22(4):2006. doi: 10.3390/ijms22042006.

Abstract

Mercury is one of the detrimental toxicants that can be found in the environment and exists naturally in different forms; inorganic and organic. Human exposure to inorganic mercury, such as mercury chloride, occurs through air pollution, absorption of food or water, and personal care products. This study aimed to investigate the effect of HgCl2 on cell viability, cell cycle, apoptotic pathway, and alters of the transcriptome profiles in human non-small cell lung cancer cells, H1299. Our data show that HgCl2 treatment causes inhibition of cell growth via cell cycle arrest at G0/G1- and S-phase. In addition, HgCl2 induces apoptotic cell death through the caspase-3-independent pathway. Comprehensive transcriptome analysis using RNA-seq indicated that cellular nitrogen compound metabolic process, cellular metabolism, and translation for biological processes-related gene sets were significantly up- and downregulated by HgCl2 treatment. Interestingly, comparative gene expression patterns by RNA-seq indicated that mitochondrial ribosomal proteins were markedly altered by low-dose of HgCl2 treatment. Altogether, these data show that HgCl2 induces apoptotic cell death through the dysfunction of mitochondria.

Keywords: H1299; RNA-seq; apoptosis; caspase-3; cell cycle arrest; human non-small cell lung carcinoma cells; mercury chloride.

MeSH terms

  • Apoptosis / drug effects*
  • Apoptosis / genetics
  • Carcinoma, Non-Small-Cell Lung / genetics*
  • Carcinoma, Non-Small-Cell Lung / metabolism
  • Carcinoma, Non-Small-Cell Lung / pathology
  • Caspase 3 / genetics*
  • Caspase 3 / metabolism
  • Cell Cycle Checkpoints / drug effects
  • Cell Cycle Checkpoints / genetics
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Cell Proliferation / genetics
  • Cell Survival / drug effects
  • Cell Survival / genetics
  • Gene Expression Profiling / methods*
  • Gene Expression Regulation, Neoplastic / drug effects
  • Gene Ontology
  • Humans
  • Lung Neoplasms / genetics*
  • Lung Neoplasms / metabolism
  • Lung Neoplasms / pathology
  • Mercuric Chloride / pharmacology*
  • Mitochondria / drug effects
  • Mitochondria / genetics
  • Mitochondria / metabolism
  • Signal Transduction / drug effects
  • Signal Transduction / genetics

Substances

  • Mercuric Chloride
  • CASP3 protein, human
  • Caspase 3