Ovarian cancer: a new biomarker
A new approach to the diagnosis of ovarian cancer
S.Kholin, Scientific.ru
Cancer of the female genital glands (ovaries) is quite widespread on our planet. It can occur at almost any age, but it is most often detected in the pre-menopausal and menopausal period. This tumor is the main cause of death of gynecological patients; for example, 15,000 patients die from it annually in the United States, putting ovarian cancer in fourth place among all factors of female mortality [1]. Usually, this malignant tumor is treated by surgical removal followed by specific chemotherapy [2]. However, despite the significant successes of modern medicine, after such treatment, patients can often experience relapses (recurrence) of the disease, which significantly worsens the prognosis.
The danger of ovarian cancer, like most malignant tumors of the female genital area, lies in the scarcity of symptoms, which is why the vast majority of cases of this oncological pathology are not detected at early stages, when treatment can give the most positive effect. The situation is complicated by the fact that ovarian cancer is often accompanied by intense metastasis (the formation of numerous secondary tumors), leading to fatal consequences. Metastases can affect not only the abdominal organs, but also distant tissues and body systems, including the lungs, bones and brain. A frequent companion of the late stages of ovarian cancer is ascites, a fluid that accumulates in the abdominal cavity.
For the diagnosis of malignant neoplasms of the female genital organs, not only gynecological examination is used, but also ultrasound, computer and magnetic resonance imaging, laparoscopy, etc. One of the most informative diagnostic methods is histological examination of the genital tissue (biopsy), which allows to accurately determine the nature and structure of the tumor, but, unfortunately, in ovarian cancer, such manipulation should be carried out with caution, since it promotes the rapid spread of the tumor process and stimulates metastasis. Therefore, over the past decade, numerous attempts have been made to introduce new diagnostic tests into gynecological practice, allowing to identify the products of metabolism and tumor growth in the blood of patients. These are the so-called markers of ovarian tumors. For example, the determination of the concentration of the tumor antigen CA-125 is widely used. However, this substance is not always present in the blood of women with ovarian cancer; in addition, its content is often increased in some diseases of internal organs, such as liver, pancreatic, lung diseases, as well as in the blood of 1% of healthy women. Therefore, there is an urgent need to develop new highly specific and sufficiently informative cancer markers of ovarian tumors not only for early diagnosis, but also for monitoring the postoperative period, evaluating the effectiveness of treatment, and timely prevention of relapses of this pathology.
A group of scientists from Germany led by Jan Dominik Kuhlmann [3] conducted a complex study to detect new markers of ovarian cancer growth. For this purpose, microfragments of ribonucleic acids (RNA) circulating in the blood of sick women were studied. These substances have different origins; they can enter the blood not only from the nuclei of tumor cells, but also from cellular organelles. Previously, the diagnostic value of some fragments of ribonucleic acids was studied, but so far it has not been possible to establish a clear correlation between the type of RNA microfragments and the localization of the tumor process.
As a result of the study, it was found that the concentration of one of the RNA microfragments, called RNU2-1f, is significantly increased in the blood of women suffering from ovarian cancer, which is not observed in both healthy women and patients after successful surgical treatment followed by chemotherapy. With the recurrence of the tumor process, the content of RNU2-1f in the blood increases.
Thus, it is proved that the RNU2-1f RNA microfragment can be used as a specific cancer marker for timely diagnosis of ovarian cancer and subsequent monitoring of the success of treatment of this disease.
- Burger et al., Incorporation of Bevacizumab in the Primary Treatment of Ovarian Cancer, N. Engl. J. Med. (2011)
- Ledermann et al., Olaparib Maintenance Therapy in Platinum-Sensitive Relapsed Ovarian Cancer, N. Engl. J. Med. (2012)
- Kuhlmann et al., Circulating U2 Small Nuclear RNA Fragments as a Novel Diagnostic Tool for Patients with Epithelial Ovarian Cancer,
Clin. Chem. (2014)
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