MECHANISMS OF GROWTH OF TRANSFORMED NEUROEPITHELIAL TUMORS

Abstract

High malignant neuroepithelial tumors are characterized by a cascade growth that features primarily the growth of tumor vessels to periphery with an involvement of tumor cells in process. With the expansion of their population by a factor of 2,
a new tumor vessel appears outside the main tumor node.
Low malignant neuroepithelial tumors are characterized by the growth of tumor mass by means of the cell population. With the two-fold rise of the cell amount, a new proliferating vessel appears which increases the stage of tumor malignancy.
Neuroepithelial tumors are contaminated by HSV in 92–93  % of all cases that is manifestated by inflammation.
The patients with neuroepithelial tumors growing on the background of the inflammatory process caused by HSV have different degrees of aggressiveness of the disease depending on the presence or absence of exacerbation signs.
Contamination of neuroepithelial tumors by HSV increases a proliferative activity of tumor cells due to increase in the amount of anti-apoptosis factor (bcl-2), two times, the endothelium of vessels three times and also increases the amount of the endothelial growth factor which is directly proportional to the expression of antibody HSV during viral replication that is accompanied by exacerbation of chronical inflammation, on which tumors are growing.
Neuroepitelhial tumors recur on the background of exacerbation of chronic inflammation in the interval: glyoblastomas – 3 to 6 months, anaplastical astrocytomas and olygodendroglyomas and ependimomas – 6 to 9 months, astrocytomas and oligodendroglyomas – 18 to 24 months.

The increase in the amount of newly formed blood vessels is the unfavorable factor and points to more early beginnings of relapse in case ofneuroepitelial tumors. For anaplastic astrocitomas, it is 25 and more, for anaplastic oligodendrogliomas – 26 and more, for glioblastomas – 37 and more.