Background & aim: Breast cancer entails 10% of all cancers in the world.  Among all types of cancers, 30 percent of women are infected with breast cancer. Non-coding of long RNA (lncRNA) is a new group of known genes in the human genome transcribed from large parts of the genome of eukaryotes and play an important role in the regulation of different biological processes. The aim of the present study was to compare the expression level of GAS5 lncRNA and NEAT1  in normal and neoplastic samples from breast cancer patients by RT-qPCR.

Methods: In the present case-control study, 40 samples from patients with breast cancer tumor and 40 patients from non-tumor under the direct supervision of a pathologist specialist due to clinical presentation and laboratory findings were collected. After extracting DNA from normal and tumor tissues, cDNA synthesis method according to the protocol and RT-qPCR was performed by SYBR®Premix Ex TaqTM II kit.  LncRNA expression levels of genes GAS5 and NEAT1 was calculated using ΔΔCT. Data were analyzed using t-test.

Results: The results of Real Time Reverse transcription-PCR indicated that partial expression levels of GAS5 lncRNA gene in tumor samples compared to normal GAS5 lncRNA of the gene, decreasing the expression, and the mean relative expression levels of lncRNA and NEAT1 gene in tumor samples compared to normal was overexpressed. These variation gene expression of LncRNA related to GAS5 about 1.5 times and 2 times to  lncRNA from  NEAT1 gene was observed respectively.

Conclusion: Due to the previous reports, these lncRNAs act as tumor suppressor in breast cancer and had differential expression in tumor and normal tissues, which could be used as biomarker for cancer diagnosis. Moreover, expression of these lncRNAs in different breast cancer subtypes and patient with other blood raises the importance of this molecules as a biomarker for cancer diagnosis and prognosis.