Guanosine monophosphate synthase upregulation mediates cervical cancer progression by inhibiting the apoptosis of cervical cancer cells via the Stat3/P53 pathway

Int J Oncol. 2021 Apr;58(4):3. doi: 10.3892/ijo.2021.5183. Epub 2021 Mar 2.

Abstract

Guanosine monophosphate synthase (GMPS) participates in chromatin and gene regulation in multiple types of organisms, and is highly expressed in a variety of human malignancies. The purpose of the present study was to explore the expression of GMPS and its role in cervical cancer (CC), and to provide ideas for improving the clinical efficacy of CC treatment. In the present study, immunohistochemistry, reverse transcription‑quantitative PCR analysis, Cell Counting Kit‑8 assay, 5‑ethynyl‑2'‑deoxyuridine assay, flow cytometry, western blotting and immunofluorescence assays were conducted to detect the expression of GMPS in normal cervical tissues, CC tissues, para‑cancerous tissues and CC cell lines. Moreover, the present study detected the effect of GMPS knockdown on CC cell proliferation, clonal formation ability, aging and apoptosis, as well as on the expression levels of apoptosis‑related proteins in tumor cells. The present results demonstrated that the expression level of GMPS in CC was significantly higher compared with that of adjacent tissues; the expression rate of GMPS in CC was 57.36%. GMPS expression was found to successively and gradually increase from that in normal cervical tissues, to that in cervical intraepithelial neoplasia and CC tissues. The abnormal expression of GMPS was positively associated with the degree of CC differentiation and the depth of early invasion. Small interfering (si)RNA knockdown of GMPS inhibited proliferation and colony formation, and promoted aging and apoptosis of CC cells. Furthermore, subcutaneous injection of GMPS‑knockdown tumor cells in nude mice resulted in a decrease in the proliferative ability of the tumor. The animal experimental results showed that the tumor growth rate of the short hairpin (sh)RNA‑GMPS group was significantly slower than that of the HeLa sh‑negative control group. It was identified that GMPS may inhibit CC cell senescence and apoptosis via the Stat3/P53 molecular pathway. Collectively, the present results suggested that GMPS may be a marker of unfavorable prognosis of CC, and it may also be a potential therapeutic target for CC.

Keywords: guanosine monophosphate synthase; cervical cancer; proliferation; senescence; apoptosis.

MeSH terms

  • Adult
  • Aged
  • Animals
  • Apoptosis / physiology
  • Carbon-Nitrogen Ligases / genetics
  • Carbon-Nitrogen Ligases / metabolism*
  • Cell Line, Tumor
  • Cell Proliferation / physiology
  • Female
  • HeLa Cells
  • Heterografts
  • Humans
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • Middle Aged
  • Prognosis
  • STAT3 Transcription Factor / genetics
  • STAT3 Transcription Factor / metabolism*
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism*
  • Uterine Cervical Neoplasms / genetics
  • Uterine Cervical Neoplasms / metabolism*
  • Uterine Cervical Neoplasms / pathology

Substances

  • STAT3 Transcription Factor
  • STAT3 protein, human
  • TP53 protein, human
  • Tumor Suppressor Protein p53
  • Carbon-Nitrogen Ligases
  • GMP synthase (glutamine-hydrolyzing)

Grants and funding

The present study was funded by the National Natural Science Foundation of China, (grant nos. 81672560, 81772773 and 81302275), the Project of Suzhou Minsheng Science and Technology (grant no. SYSD2019204) and the Project of Suzhou Science and Technology Development Plan (grant no. SLJ202006).