[Characteristics of PIK3CA gene mutations in Her2-low breast cancer]. / Kharakteristika mutatsii gena PIK3CA pri rake molochnoi zhelezy s nizkim urovnem ekspressii belka Her2/neu.

BACKGROUND: Mutations in the PIK3CA gene, encoding the catalytic subunit of the PI3K class IA p110α, is a common mechanism of activating of PI3K/AKT/mTOR pathway in breast cancer (BC). The detection of these mutations in patients with hormone-positive Her2-negative BC is of important clinical value, since they are the predictor of the sensitivity of the tumor to the PI3K inhibitor - alpelisib. According to the status of the Her2/neu expression, all patients with hormone-positive Her2-negative BC can be divided into two groups - with low expression of Her2/neu (IHC 1+; 2+, ISH-) and with a complete lack of expression of this protein (IHC 0). OBJECTIVE: Establish whether there are differences of the PIK3CA gene mutations charasteristics in BC with luminal immunophenotype and low expression of Her2/neu in comparison with tumors in which Her2/neu expression is absent. MATERIAL AND METHODS: The presence of PIK3CA mutations was determined using real-time PCR on 96 patient tissues of hormone-positive Her2-negative BC. Commercially available cobas PIK3CA Mutation Kit (Roche) and cobas z480 analyzer were used. RESULTS: PIK3CA gene mutations were detected in 40 of 96 cases studied (41.6%). Most of them were localized in the exons 9 and 20, encoding helicase (p.E542K, p.E545X) or kinase (p.H1047X) domains of PI3K, respectively. The frequency of mutations in the exon 9 (p.E542K+p.E545X) was 2.6 times higher in Her2-low BC compared to tumors in which the Her2/neu expression was absent (p<0.05). There were no statistically significant differences in mutation frequency in the exon 20. CONCLUSION: Statistically significant increase in the frequency of exon 9 mutations of the PIK3CA gene is specific for the group of patients with Her2-low BC. Our results supported the concept of Her2-low BCs as the unique entity and pointed out the need of their further study.

[HER2/neu gene amplification as a mechanism of clonal heterogeneity in breast cancer]. / Amplifikatsiia gena HER2/neu kak mekhanizm vozniknoveniia klonal'noi geterogennosti pri rake molochnoi zhelezy.

OBJECTIVE: To estimate the heterogeneity of HER2/neu gene amplification in HER2/neu-positive breast cancer (BC). MATERIAL AND METHODS: Fluorescence in situ hybridization (FISH) assay was used to estimate HER2/neu gene amplification and HER2/CEP17 ratios in BC samples with an immunohistochemical evaluation of HER2/neu2+ expression. The results were interpreted according to the 2018 ASCO/CAP guidelines. BC samples with HER2/neu gene amplification (n = 25) was evaluated for variability in HER2/neu amplification and HER2/CEP17 ratios in 20 tumor cells counted using the FISH assay. RESULTS: Significant intratumoral variability was found in the HER2/neu gene copy number and HER2/CEP17 ratios. HER2/neu-negative cells (5-15%) were present in 28% of the examined samples found to be HER2/neu positive. The HER2/neu gene copy number and HER2/CEP17 ratios for these tumors were statistically significantly lower than those in the group in which all the counted cells were characterized by HER2/neu amplification: 6.25 (95% CI 4.3-12.45; p=0.0166) and 2.37 (95% CI 2.06-3.43; p=0.0076), respectively. The threshold value of HER2/CEP17, at which cells without amplification were detected in HER2/neu-positive tumors, was 2.5. CONCLUSION: HER2/neu gene amplification in BC is extremely variable both within a single tumor and between the tumors of the same biological subtype. Amplification heterogeneity is statistically significantly more common in HER2/neu-positive BC with a HER2/CEP17 ratio <2.5 and may affect the outcome of the disease and also be important in the choice of treatment policy.

[Morphological evidence of the ischemic nature of the prostatic fibrosis in the classical chronic pelvic pain syndrome / IIIB chronic prostatitis].

AIM: To examine the structure of the prostate tissue in patients with III B chronic prostatitis (CP) and chronic pelvic pain syndrome (CPPS). MATERIALS AND METHODS: The study analyzed transrectal fine-needle biopsy specimens of 10 patients with the verified diagnosis of chronic pelvic pain syndrome/category III B chronic prostatitis (CPPS/IIIB CP) according to the National Institutes of Health classification. Tissues were examined using light and electron microscopy, and immunohistochemical study of the expression of CD31, CD34, NSE and S-100 markers. RESULTS: All biopsy specimens of all patients showed fibroplastic changes of the prostate tissue most markedly pronounced in the stroma and muscle fibers in the form of total fibrosis, myofibril atrophy, and extracellular lipofuscin deposition. The examination revealed a significant reduction in the density of microcirculatory bed vessels and arteriolar luminal stenosis, a reduction in the number of nerve fibers, and compression of their fibrous tissue. No inflammatory changes were found in the prostate. DISCUSSION: In patients with CPPS/IIIB CP, the changes in the prostate at the microscopic and ultrastructural levels are characteristic of severe chronic tissue hypoxia, which leads to the development of fibrosis resulting in stenosis of microcirculatory bed vessels and degenerative changes in nerve fibers and cells. No signs of an inflammatory reaction in the examined tissue were established. CONCLUSION: Changes in the prostate tissue in CPPS/IIIB CP suggest the presence of chronic pelvic ischemia and exclude its association with inflammation as the main pathological process.

[Connexin 43 expression in human brain glial tumors]. / Ékspressiia konneksina 43 v glial'nykh opukholiakh golovnogo mozga cheloveka.

AIM: Тo conduct an immunohistochemical (IHC) study of the expression of connexin 43 in the samples of glial tumors of various grades: gemistocytic astrocytomas (Grade 2), oligodendrogliomas (Grade 2) and glioblastomas (Grade 4). MATERIAL AND METHODS: The material investigated was fragments of human brain glial tumors (grade 2 gemistocytic astrocytomas (n=2), grade 2 oligodendrogliomas (n=2), and grade 4 glioblastomas (n=14) and those of tumor-surrounding tissue (n=4). The material was fixed in 10% buffered formalin, dehydrated, and embedded in paraffin according to the standard technique. IHC studies of the slices applied primary rabbit polyclonal antibodies against connexin 43 ('Spring Bioscience', USA) and the Dako EnVision + Peroxidase (DAB) visualization system ('Dako', Denmark). After the immunohistochemical reaction, the cell nuclei were stained with Mayer's hematoxylin. RESULTS: Immunohistochemistry showed the changing pattern of connexin 43 expression as compared with intact tissue in the glial tumors. Instead of the fine-granular expression in the thin cellular processes in the neuropil, the tumors mainly displayed a coarse-grained cytoplasmic and even nuclear reaction. The morphology and localization of positive structures depended on the variant of an examined tumor. In addition, the most malignant brain gliomas generally exhibited a reduction in the expression of connexin 43, i.e. its quantity is inversely proportional to the degree of malignancy of the tumor. CONCLUSION: The low connexin 43 expression levels may reflect both a reduction in astroglial functional gap junctions and semicanals and a decrease in the amount of the protein itself that has independently antioncogenic properties. The observed cytoplasmic and nuclear expression of connexin 43 is most likely to be associated with the aberrant activity of a number of kinases, such as proto-oncogene tyrosine-kinase Src or protein kinase C (PKC).

[Secondary monoclonal gammopathy after bone marrow autotransplantation as a cause of worse renal function in light chain immunoglobulin deposition disease].

The paper describes a clinical case of a female woman with nephropathy due to light chain deposition disease caused by secretion of κ Bence-Jones protein. Complete immunochemical remission was achieved after induction therapy using a bortezomib + cyclophosphamide + dexamethasone regimen. Renal function remained unchanged (glomerular filtration rate 16 ml/min), there was a reduction in proteinuria from 5.8 to 2.6 g/day. High-dose melphalan (200 mg/m2) chemotherapy with peripheral blood stem cell autotransplantation was performed as consolidation of remission. A year posttransplantation, there was no secretion of κ light chains; however, monoclonal IgG lambda emerged in a quantity of 3.2 g/l. At the same period, nephrotic syndrome became progressive (daily proteinuria 12 g) and dialysis-dependent renal failure developed. A repeat renal biopsy specimen revealed changes, suggesting that there was a decrease in renal deposits of κ light chains. Simultaneously with this, the obvious negative trend as progressive nephrosclerosis and fixation of IgG and λ light chains in the glomeruli (in the sclerotic areas) cause IgGλ monoclonal protein to be involved in the genesis of further kidney injury. Attention is also paid to different characteristics of capillary wall deposits by density (according to the electron microscopic findings), which may point to their different qualitative composition and possibly different formation duration. Papaprotein Gλ disappeared after a year without therapy, suggesting its reactivity. The findings confirm that worse renal function is caused by the action of paraprotein Gλ due to secondary (after autologous hematopoietic stem cells transplantation) monoclonal gammopathy.

[Neuronal and glial antigen distribution in the columns of somatosensory cortex of rat brain (an immunohistochemical study)].

The aim of the study was to detect the neocortical columns in the S1 field on frontal sections of brain of albino rats using the method of immunohistochemistry and the antibodies against neuronal (synaptophysin, neurofilament) and gliocyte (glial fibrillary acidic protein--GFAP, myelin basic protein) proteins. The examination of the expression of the major neurospecific antigens revealed that on thin sections (4 micromin) a column could be identified due to accumulations of the astrocytes and neuronal processes--axons and dendrites. GFAP expression study also showed that cortical layer I usually contained multiple large astrocytes with branching processes, as well as numerous smaller processes with high intensity of expression. Synaptophysin content was high in all the layers of the cortex, but the most intense reaction was detected in the molecular layer, similarly with the intensity of GFAP reaction. The expression of myelin basic protein was detected in accordance with the radially extending myelinated processes of the neurons in the cortex.

[Different Her-2 status in infiltrative and intraductal components of the breast cancer].

In the article a breast cancer case with different Her2 status in invasive and non-invasive components is described. We emphasize on the importance of knowledge about tumor histology for correct interpretation of FISH Her2-test results.

[HER-2/neu-testing in breast cancer: is the immunocytochemistry competent?].

According to ASCO/CAP guidelines, there are two recommended methods for Her2/neu-testing in breast cancer patients such as immunohistochemistry and fluorescence in situ hybridization. This paper analyses results of alternative immunocytochemical method for Her2/neu detection and its diagnostic pitfalls.

[Analysis of spatial arrangement of gap junctions in respect to chemical synapses in the serial ultrathin sections of rat barrel cortex].

Electron microscopic investigation of gap junctions (GJ) on serial sections of rat barrel cortex has shown that GJ were in contact with one or both processes that formed chemical synapses, however, these connections could not traced in single sections. In the serial sections, it was possible to observe two GJ in the immediate proximity to one another, in a single field of vision, thus, each GJ was traced in two or three successive sections in a series. Considering the described variants of GJ arrangement in the cortex, it is suggested that GJ could be a structural basis for local synchronization of the bioelectrical activity not only at postsynaptic, but also at presynaptic level, and the formation of GJ occurs both before, and after the development of chemical synapses.

[Bcl-2 as a prognostic factor in different molecular genetic subtypes of breast cancer].

It is well known that breast cancers (BC) are divided into 4 molecular genetic subgroups (luminal A, luminal B, HER2/neu-positive, and triple-negative (TNBC). The purpose of the investigation was to comparatively estimate the pattern of expression of Bcl-2, known as a good prognostic marker of BC, in different molecular genetic subgroups and to study the correlation of this protein with proliferative activity index and genetic aberrations on chromosome 17. The investigation covered 290 samples of invasive ductal BC. Bcl-2 expression was identified in 14% of HER2/neu-positive and TNBC cases while 77% of luminal B tumors and 100% of luminal A ones expressed Bcl-2. Loss of Bcl-2 expression correlated with clinically more aggressive BCs having a high proliferative activity and amplification of HER2/neu and chromosome 17 centromere. This may suggest the poor prognosis of luminal B, HER2/neu-positive and TNBC with no Bcl-2 expression and calls for further investigations on larger samples.

[Structural organization of the barrel cerebral cortex in rat (an immunohistochemical study)].

Immunohistochemical investigation of the regional distribution of neuronal and glial elements in the barrels of somatic cortex was carried out in rats (n=10). High level of synaptophysin protein expression was detected in the in barrel walls together with the accumulation of astroglial cells in their central areas. Ultrastructural investigation of chemical synapse structure showed the predominance of asymmetrical perforated axospinous contacts, presumably of excitatory type. The symmetric inhibitory synapses were more frequently located in the barrel walls in the areas of the denser neuronal perikarya distribution, as well as on the large dendritic processes. The number of vertically oriented myelinated axons within the barrels was found to be significantly greater than the number of the horizontally oriented interneuronal circuits.

Role of gap junctions in local rhythmogenesis in cortical columns.

Complex morphofunctional studies of the barrel cortex of the rat identified and analyzed the ultrastructural characteristics of the dendrodendritic electrical synapses--gap junctions (GJ)--of stellate neurons of barrels D2-D3. The local nature of dendrite branching of barrel cells, limited to the volume of the barrel, suggests that these GJ, which account for 7% of all synapses, may be the structural basis of local intrabarrel electrotonic synchronization of pacemaker potentials of barrel neuron hyperpolarization on development of spindle-type activity in the corresponding column.

[The role of gap junctions in the local rhythmogenesis in the cortical columns].

Ultrastructural characteristics of electrical dendro-dendritic synapses (gap junctions (GJ) of stellate neurons of D2-D3 barrels were detected and analyzed in the complex morpho-functional investigations of rat barrel cortex. Considering the local character of dendritic branching of the barrel cells, which is limited by the borders of a single column, it may be suggested that GJ which account for only 7% of the whole number of synapses, may be the structural base of local intracolumnar electrotonic synchronization of pacemaker hyperpolarisation potentials of barrel neurons during the development of spindle activity in the corresponding column.

[Morphological characteristics and intracellular electrolytic composition of blood cells at surgeries on lower extremities arteries].

Morphological characteristics and trace and macroelement composition of blood cells flowing out of ischemic lower limb before, during and after reconstructive surgeries under different type of anesthesia. A total of 102 male patients aged 45 to 60 years with atherosclerotic occlusions of the arteries of the femoral-popliteal zone were included into the study. According to anesthesia type all the patients were divided into 3 groups: group 1 consisted of 34 patients operated under spinal anesthesia, 37 patients of group 2 underwent surgery under combined anesthesia (spinal anesthesia with intravenous sedation), 31 patients of group 3 - under total intravenous anesthesia with myoplegia and artificial pulmonary ventilation. All the blood examinations were carried out with scanning electron microscope XL-30 ("Philips") and X-ray spectrum microanalyzer Edax ( "Edax International", USA). It is demonstrated that in spinal and combined anesthesia morphological characteristics of blood cells normalized due to optimization of intraerythrocytic and intrathrombocytic electrolytic homeostasis unlike total intravenous anesthesia, when intracellular imbalance of trace and macroelements progresses and ultrastructural cellular alterations persist.

[Endothelial function and cellular morphology and functionality inischemic limbs during drug therapy of obliterative atherosclerosis].

UNLABELLED: The aim of the study was to develop a rationale for Vasaprostan monotherapy of ischemia in patients with obliterative lesions in lower limb arteries. The assessment of blood cell ultrastructure revealed deformation of erythrocytes and platelets, aggregation of platelets and platelets with red cells, evidencing severe rheological alterations and increased incidence of thrombotic events in patients with critical ischemia. Vasaprostan monotherapy was more effective then combined therapy without prostaglandin E1. In patients with lower limb occlusive arterial lesions and different ischemic grades Vasaprostan alleviated endothelial dysfunction and normalized different morphological and functional parameters of erythrocytes and platelets. The trend toward ultrastructural normalization was evident in all patients after Vasaprostan administration. This trend was proved by changes in elemental composition of erythrocytes. CONCLUSION: Vasaprostan is beneficial for patients with obliterative lesions in lower limb arteries and can be used as monotherapy or preoperative management for stimulation of volumetric blood flow and blood supply of ischemic tissues.

[Kidney carcinosarcoma]. / Kartsinosarkoma pochki.

A kidney tumour in a 36 year old female is described. The tumor was soft, of gray-brown color, size 12 x 11 cm. Histological, immunohistochemical and ultrastructural findings have demonstrated the signs of biphasic epithelial and mesenchymal cell differentiation. These data allowed the authors to define this tumor as a renal carcinosarcoma. Histogenesis of this tumor and differential diagnosis with other malignant renal tumors are discussed.

[A morphometric study of the ultrastructure of the axosomatic synapses in the sensorimotor cortex of rats administered the delta-sleep inducing peptide]. / Morfometricheskoe issledovanie ul'trastruktury aksosomaticheskikh sinapsov sensomotornoi kory mozga krys pri vvedenii del'ta-son indutsiruiushchego peptida.

Qualitative estimation and quantitative morphometry of ultrastructural changes in layers III, IV, and V in rat sensomotorial cortex after delta-sleep-inducing peptide administration, provides an evidence of multiplication of active inhibitory synapses induced by DSIP. The newly activated synapses may form an axo-somatic synaptic pool participating in optimization of the balance of excitement and inhibition processes in sensomotorial cortex.

[The electrophysiological and ultrastructural aspects of the effect of increased oxygen pressure on the sensorimotor cortex of rats]. / Elektrofiziologicheskie i ul'trastrukturnye aspekty vliianiia povyshennogo davleniia kisloroda na sensomotornuiu koru golovnogo mozga krys.

Stay of the rats in barochamber under 0.3 MPa oxygen during 2 hrs induced separate sharp waves with no generalisation, the electron microscopic changes expressing activation of compensatory-adaptive processes. The generalisation of seizure activity over the cortex at 0.7 MPa oxygen affects a part of neuronal pool due, probably, to irreversible changes in inhibitory axosomatic synapses.