Tumor Biology

, Volume 36, Issue 4, pp 2809–2814 | Cite as

7SK small nuclear RNA inhibits cancer cell proliferation through apoptosis induction

Research Article


7SK small nuclear RNA (snRNA) is a 331–333-bp non-coding RNA, which recruits HEXIM 1/2 protein to inhibit positive elongation factor b (P-TEFb) activity. P-TEFb is an essential factor in alleviating promoter-proximal paused RNA polymerase II (Pol II) and initiating the productive elongation phase of gene transcription. Without this protein, Pol II will remain in its hypophosphorylated state, and no transcription occurs. In this study, we inhibited P-TEFb activity by over-expressing 7SK snRNA in human embryonic kidney (HEK) 293T cancer cell line. This inhibition led to a significant decrease in cell viability, which can be due to the transcription inhibition. Moreover, 7SK snRNA over-expression promoted apoptosis in cancerous cells. Our results suggest 7SK snRNA as a potential endogenous anti-cancer agent, and to the best of our knowledge, this is the first study that uses a long non-coding RNA’s over-expression against cancer cell growth and proliferation.


7SK snRNA lncRNA Cancer Transduction 

Supplementary material

13277_2014_2907_MOESM1_ESM.jpg (155 kb)
Figure S1 a. Gel electrophoresis image of 7SK snRNA cloned into pCDH-H1 vector, lanes from left to right are correspond to 1 kb ladder, undigested pCDH-7SK vector, pCDH-7SK digested with BamHI, and pCDH-7SK digested with BamHI and EcoRI. 330 bp band relates to cloned 7SK snRNA. b. Gel electrophoresis image of pCDH-H1 vector before cloning. (JPEG 154 kb)


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Copyright information

© International Society of Oncology and BioMarkers (ISOBM) 2014

Authors and Affiliations

  1. 1.Department of Biotechnology, College of ScienceUniversity of TehranTehranIran
  2. 2.Biotechnology Department, School of MedicineShahid Behashti University of Medical SciencesTehranIran
  3. 3.Department of Molecular Biology and Genetic EngineeringStem Cell Technology Research CenterTehranIran
  4. 4.Department of Immunology, School of MedicineAlborz University of Medical SciencesKarajIran
  5. 5.Department of Hematology, Faculty of Medical ScienceTarbiat Modares UniversityTehranIran

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