K-Ras 4A Transcript variant is up-regulated in eutopic endometrium of endometriosis patients during proliferative phase of menstrual cycle

Aims K-Ras transcripts comprise two main isoforms: K-Ras 4A and K-Ras 4B, which act differently. The expression of both isoforms was reported in many human tissues. However, K-Ras 4B was the major expressed transcript variant. An increased expression of K-Ras 4B mRNA was reported in eutopic endometrium of endometriosis patients. In this way, we aimed to study the expression of K-Ras 4A transcript in eutopic endometrium related to endometriosis.

Employing exon4-flanking primers, K-Ras isoforms were simultaneously amplified in a RT-PCR reaction. Quantitative real-time PCR was performed using GAPDH as an internal control. K-Ras 4A transcript expression in eutopic endometrium was analyzed by ΔΔC T method.

We identified existence of both of K-Ras 4A and K-Ras 4B in eutopic endometrium of patients and controls. Quantitative real-time analysis demonstrated that K-Ras 4A expression was 2.7-fold higher in endometriosis than non-endometriosis eutopic samples. Interestingly, this overexpression mainly occurs through the proliferative phase of menstrual cycle.

The findings bring to light the eminent role of K-Ras 4A in endometriosis. This splice variant which is known for promoting apoptosis could be an effective factor in balance between proliferation and death of eutopic endometrial cells. Similar content being viewed by others

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