TSitologiya i Genetika 2022, vol. 56, no. 2, 70-72
Cytology and Genetics 2022, vol. 56, no. 2, 172–178, doi: https://www.doi.org/10.3103/S0095452722020104



  1. Department of Medical Biology, Faculty of Medicine, Hatay Mustafa Kemal University, Hatay, Turkey
  2. Department of Molecular Biochemistry and Genetics, Graduate School of Health Sciences, Hatay Mustafa Kemal University, Hatay, Turkey
  3. Department of Medical Services and Techniques, Vocational School of Health Services, Hatay Mustafa Kemal University, Hatay, Turkey
  4. Department of Physiotherapy and Rehabilitation, Faculty of Health Sciences, Sakarya University of Applied Sciences, Sakarya, Turkey

«Cancer stem cells» (CSCs), can initiate tumorigenesis and metastasis and show resistance against chemotherapy owing to the expression of prominent stem cell markers. CSCs are a subpopulation of highly heterogenic cancer spheroid cells. Pigment epithelium-derived factor (PEDF) is a neurotrophic, anti-tumorigenic, and anti-metastatic protein and its gene expression levels in A549 spheroids is still unknown. We aimed to compare clonogenicity and mRNA levels of PEDF, Oct4, and ALDH1A1 between A549 and spheroid cells. Spheroid and colony formation assays were performed with spheroid and A549 cells. We performed quantitative reverse transcription-polymerase chain reaction (qRT-PCR) for gene expression analysis. The clonogenic ratios for A549 and spheroids were ~60 % and ~1 % respectively. During spheroid formation, Oct4 mRNA level did not change but PEDF and ALDH1A1 levels decreased significantly. CSCs are characterized by elevated stem cell markers but spheroid cells consist of heterogeneous population including CSCs. In spheroid population, no increase in stem cell markers was observed. The reduced PEDF levels during spheroid transition can be a suppression mechanism of spheroid cells.

Keywords: lung cancer, PEDF, A549, spheroid cell, Oct4, ALDH1A1

TSitologiya i Genetika
2022, vol. 56, no. 2, 70-72

Current Issue
Cytology and Genetics
2022, vol. 56, no. 2, 172–178,
doi: 10.3103/S0095452722020104

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