International Medical Journal, Vol. 21., Iss. 4, 2015, P. 61−65.
PROSPECTS OF THE USE OF MOLECULAR MARKERS IN CANCER OF OVARIES
S. P. Grigoriev Institute for Medical radiology, NAMS of Ukraine, Kharkiv, Ukraine
Cancer of ovaries is one of the most urgent and difficult issues of clinical oncology. It makes about 30 % of all gynecological malignant diseases and is responsible for almost fifty percent of death among them. The present−day success of molecular−genetic research in oncology allows to consider malignancy as illness characterized by clonal evolution of transformed cells in the tissue. Importance of laboratory diagnosis ovarian cancer is undoubtful as in 10−20 % of cases biopsy cannot give the material containing tumor cells. Determination of molecular−biological markers in the tumor tissue can give additional information about biological behavior of the tumor, about the quickness of her growth, capacities to metastasize and invade the tissues, stability to chemotherapy. At present much attention is paid to the study of markers, characterizing apoptosis, proliferation of cell and angiogenesis including p53, Bcl−2, Ki−67 and VEGF proteins. Expression of р53 in the tumor tissue can serve as a marker to forecast survival of patients and resistance to adjuvant therapy. Activity of р53 is required for some forms of apoptosis, and its mutations are associated with the aggressiveness of the disease course and stability of tumor cells to chemotherapy or radiation therapy. Proteins Bcl (Bcl−2 and Bax) play a key role in apoptosis inducing or inhibiting it. The majority of researchers believe that expression of Bcl−2 is not the prognostic factor of efficiency of chemotherapy at cancer of ovaries. However others suppose that stability of tumors to chemotherapy, starting apoptosis, is due to the high level of Bcl−2 production. Proliferative activity of the tumor can be assessed by the degree of Кі−67 expression. Correlation between the amount of cells, expressing Кі−67 and the degree of malignancy has been established. The tumors expressing Кі−67 in over 20 % of cells suggest a high risk of relapse. Expression of VEGF in malignant tumors combines with strengthening of its metastatic activity and shortening of progression−free survival. VEGF has been established to be present in tumors in 97 % of patients with ovarian cancer, in 56 % of patients the expression was estimated as expressed. There is direct correlation between frequency of VEGF expression and stage of disease (stage 1−2 −− 13.5 %, stage 3 −− 41.4 %). The publications about the clinical value of these markers for the patients with ovarian cancer are not numerous. Markers p53, Bcl−2, Ki−67 and VEGF play an important role in disease development and can influence the results of treatment and survival. Meantime complex study of markers of apoptosis, proliferation and angiogenesis has not been conducted yet, validating practical expediency and prospects of these works.
Key words: cancer of ovaries, molecular−biological markers, apoptosis, proliferation, angiogenesis.