RNA Concentration and Content in the Nucleoli and Cytoplasmic Rim in Differentiating Lymphocytes of Patients Suffering from B Chronic Lymphocytic Leukaemia - a Cytochemical Note.

Nucleolar RNA optical density (concentration) measurements at the single cell level indicated that differentiation of lymphocytes is accompanied by a slightly decreased nucleolar RNA concentration in contrast to the cytoplasmic rim around the nucleus. On the other hand, the nucleolar size was markedly reduced and the cytoplasmic rim surrounding the nucleus was reduced only weakly. Concerning the calculated rough estimate of the RNA content, the differentiation induced its larger decrease in the nucleoli than in the cytoplasmic rim. These observations indicated that the nucleolar RNA concentration and RNA content together with the nucleolar morphology are more sensitive markers of the differentiation process than the RNA concentration and content in the cytoplasm. Thus, the nucleolar RNA transfer to the cytoplasm in advanced differentiation steps might still be going on regardless of the decreasing or inhibited nucleolar biosynthetic activity. In addition, the presence of ring-shaped nucleoli and micronucleoli characteristic of mature and terminal lymphocytes in some lymphocytic less differentiated steps, i.e., lymphoblasts and prolymphocytes, might indicate the premature differentiation state of such cells.

The Morphology of Cell Differentiation, Terminal Differentiation and Ageing Seems To Reflect the Same Process: a Short Note.

Based on simple microscopic cell morphology in blood and bone marrow smear preparations, it seems to be likely that the cell differentiation and terminal differentiation in human blood cells, and particularly in erythroid or granulocytic lineages, simultaneously reflect ageing of the lineage progenitors and terminal differentiation steps. The terminal differentiation stages of both these lineages actually appear as senescent cells. Abnormal ageing of progenitor cells may represent one of the "dysplastic" phenomena of the premature terminal differentiation state. Such state is characterized by heterochromatin condensation and nucleolar morphology similar to that in fully differentiated terminal cells of granulocytic or erythroid lineages. It should also be mentioned that in some known erythropoietic disorders, less differentiated erythroblasts may lose nuclei similarly as "normal" fully terminally differentiated cells of the erythroid cell lineage. It seems to be clear that cells in both abnormal less differentiated and terminally differentiated stages of erythroid or granulocytic lineages lose the ability to multiply similarly as senescent cells. On the other hand, the background of cell ageing and differentiation is very complicated and requires a different approach than the simple microscopic morphology at the single cell level. However, the morphology and clinical cytology at the single cell level might still contribute with complementary data to more sophisticated complex studies of that topic. In addition, the morphological approach facilitates the study of the main components of single cells in various states, including the differentiation steps or ageing.

Dominant Nucleolus in the Progenitor Cell Using Human Bone Marrow Erythroid and Granulocytic Cell Lineages as a Model. A Morphological and Cytochemical Note.

Progenitor cells of the human erythroid and granulocytic cell lineages are characterized by the presence of several nucleoli. One of these nucleoli is larger and possesses more fibrillar centres than others. Such nucleolus is apparently dominant in respect of both size and main nucleolar function such as nucleolar-ribosomal RNA transcription. Such nucleolus is also visible in specimens using conventional visualization procedures, in contrast to smaller nucleoli. In the terminal differentiation nucleated stages of the erythroid and granulocytic development, dominant nucleoli apparently disappeared, since these cells mostly contained very small nucleoli of a similar size with one fibrillar centre. Thus, the easily visible dominant nucleoli appear to be useful markers of the progenitor cell state, such as proliferation, and differentiation potential.

Genistein Induces Bcl-2 Expression in Human Dermal Microvascular Endothelial Cells: a Short Report.

It has been shown previously that oestradiol protects the vascular network, leading to increased skin flap viability associated with Bcl-2, VEGF and FGF-2 up-regulation. We have shown that genistein, a natural selective oestrogen receptor modulator, also increases skin flap viability in rats and induces Bcl-2 expression in human umbilical vein endothelial cells. In the present study we aimed to answer the question whether genistein increases expression of Bcl-2, a potent anti-apoptotic protein, in human dermal microvascular endothelial cells (HMVEC-d) as well. Our results showed that administration of genistein induces Bcl-2 expression in a concentration-dependent manner. Cell co-treatment with genistein and anti-ER compounds (MPP, PHTPP, ICI, G-15) diminished the observed positive effect of genistein on Bcl-2 expression. The decrease in Bcl-2 expression in HMVEC-d was most prominent after co-treatment with ICI (nuclear ER antagonist/ GPR30 agonist) and PHTPP (selective ER-ß antagonist). In conclusion, genistein increases Bcl-2 expression in HMVEC-d, contributing to its protective effect on the skin flap viability. However, the question whether the mechanism is ER-specific (via ER-ß) has to be answered in further studies using a model of gene silencing or genetically modified cells.

Genistein and Selected Phytoestrogen-Containing Extracts Differently Modulate Antioxidant Properties and Cell Differentiation: an in Vitro Study in NIH-3T3, HaCaT and MCF-7 Cells.

During the last decades, plant extracts containing phytoestrogens have increasingly been used as an alternative to oestradiol hormone replacement therapy. The aim of the present study was to compare the effects of genistein with those of different phytoestrogen-containing plant extracts (from red clover flowers and soybeans) on the proliferation and differentiation of NIH-3T3, HaCaT and MCF-7 cells. Our results showed poor correlations between direct anti/pro-oxidant effects and cytotoxicity of the tested samples. In contrast, genistein showed a direct correlation between significant pro-oxidative effects at cytotoxic concentrations and almost no pro-oxidative effects at non-cytotoxic concentrations. Moreover, the tested red clover extract and genistein induced keratin-8 (luminal and prognostic marker in breast cancer) expression only in MCF-7 cells, but this effect was not seen following treatment with the soybean extract. From this point of view, the effect of consumption of phytoestrogens in oestrogen-positive breast cancer remains to be elucidated. In conclusion, our study demonstrates that various phytoestrogen- containing plant extracts and genistein are able to specifically modulate antioxidant properties and differentiation of studied cells.

To the Nuclear Region Occupied by Nucleolar Bodies in Human Leukaemic Myeloblasts of Kasumi 1 and K 562 Lineages.

Previous observation demonstrated that measured nucleolar and nuclear diameters and the resulting calculated ratio might facilitate estimation of the approximate size of the nuclear region occupied by the nucleolar bodies. The size of nuclear regions occupied by nucleolar bodies decreased during the differentiation and maturation of leukaemic lymphocytes, but was constant for each differentiation or maturation stage. The present study was undertaken to provide more information on the approximate size of the nuclear regions occupied by nucleolar bodies in leukaemic granulocytic progenitors. Myeloblasts of established Kasumi 1 and K 562 cell lineages originating from human myeloid leukaemias were convenient models for such study because they represented only one and early differentiation stage of granulocytic progenitors. According to the results, the maximal and mean nucleolar body : maximal and mean nuclear diameter ratios in myeloblasts without heavy nuclear alterations were stable and not markedly influenced by the anti-leukaemic treatment or aging. Thus, the roughly estimated size of nuclear regions occupied by nucleolar bodies in these cells appeared to be similar and stable regardless of aging or anti-leukaemic treatment. In contrast, the anti-leukaemic treatment or aging in such myeloblasts induced marked reduction of the nucleolar biosynthetic activity reflected by the decreased number of nucleolar fibrillar centres.

Morphometric and Densitometric Analysis of Heterochromatin during Cell Differentiation Using the Leukaemic Granulocytic Lineage as a Convenient Model.

Granulocytic early progenitors and terminally differentiated - mature granulocytes with segmented nuclei were studied using computer-assisted diameter and heterochromatin optical image densitometry to provide more information on the nuclear size and heterochromatin condensation state. Bone marrow smears of patients suffering from chronic myeloid leukaemia untreated as well as treated with "specific" anti-leukaemic therapy with imatinib mesylate are a convenient model for such study because they possess a satisfactory number of cells for diameter and optical density measurements. In addition, the identification of developmental stages of granulocytes is very easy and the morphology is not different from that in not-leukaemic persons. As it was expected, the mean diameter of nuclear segments in fully differentiated and mature granulocytes was much smaller than that in non-segmented nuclei of early granulocytic precursors. Therefore, no wonder that the heterochromatin condensation state in nuclear segments of mature granulocytes was much larger than in non-segmented nuclei of granulocytic progenitors. On the other hand, the sum of mean diameters of all nuclear segments per cell was close to the mean nuclear diameter of early granulocytic progenitors. The heterochromatin condensation state in granulocytic progenitors or fully differentiated mature granulocytes exhibited marked stability and did not change after the anti-leukaemic therapy. In addition, Barr bodies of characteristic drumstick appearance bearing inactive X chromosome in interphase nuclei of mature granulocytes in fertile female patients exhibited a heterochromatin condensation state similar to nuclear segments. This heterochromatin condensation state was also stable and constant, and was not apparently influenced by the anti-leukaemic therapy.

To the Large Nucleolar Bodies in Apoptotic Leukaemic Granulocytic Progenitors without Further Differentiation. Are Large Nucleoli Always Present in Proliferating Cells?

Large nucleoli have generally been believed to be present in less differentiated and proliferating cells including the malignant ones. Such nucleoli have also been considered to be active in the biosynthetic process and major cell developmental activities. In contrast, after cytostatic treatment, apoptotic leukaemic progenitors still containing nuclei did not exhibit substantial reduction of the nucleolar size but displayed decreased nucleolar biosynthetic activity. The present study was undertaken to provide more information on the large nucleoli in spontaneously occurring apoptotic leukaemic progenitors without further differentiation. Leukaemic progenitors of established cell lineages originating from leukaemic patients represented a very convenient model for such study. Some of them exhibit morphological signs of the spontaneously occurring apoptotic process. Since such signs are expressed by nuclear and cytoplasmic morphological variability, the present study dealt with spontaneously occurring apoptotic progenitors with preserved nuclei characterized by heavy chromatin condensation and occasional fragmentation. Based of nucleolar body and nuclear maximal diameter measurements it seems to be clear that the nucleolar size in these cells was not substantially reduced, contrary to that of the nucleus. However, large nucleolar bodies in spontaneously occurring apoptotic cells were characterized by markedly reduced biosynthetic activity, as expressed by the decreased number of nucleolar transcription markers such as nucleolar fibrillar centres. In conclusion, large nucleoli may be present not only in proliferating, but also in spontaneously occurring apoptotic cells.

Rho GTPase Rac1: molecular switch within the galectin network and for N-glycan α2,6-sialylation/O-glycan core 1 sialylation in colon cancer in vitro.

The Rho GTPase Rac1 is a multifunctional protein working through different effector pathways. The emerging physiological significance of glycanlectin recognition gives reason to testing the possibility for an influence of modulation of Rac1 expression on these molecular aspects. Using human colon adenocarcinoma (SW620) cells genetically engineered for its up- and down-regulation (Rac1+ and Rac1- cells) along with wild-type and mock-transfected control cells, the questions are addressed whether the presence of adhesion/growth-regulatory galectins and distinct aspects of cell surface glycosylation are affected. Proceeding from RT-PCR data to Western blotting after two-dimensional gel electrophoresis and flow cytofluorimetry with non-crossreactive antibodies against six members of this lectin family (i.e. galectins-1, -3, -4, -7, -8 and -9), a reduced extent of the presence of galectins-1, -7 and -9 was revealed in the case of Rac1 cells. Application of these six galectins as probes to determination of cell reactivity for human lectins yielded relative increases in surface labelling of Rac1- cells with galectins-1, -3 and -7. Examining distinct aspects of cell surface glycosylation with a panel of 14 plant/fungal lectins disclosed a decrease in α2,6-sialylation of N-glycans and an increase in PNA-reactive sites (i.e. non-sialylated core 1 O-glycans), two alterations known to favour reactivity for galectins-1 and -3. Thus, manipulation of Rac1 expression selectively affects the expression pattern within the galectin network at the level of proteins and distinct aspects of cell surface glycosylation.

Towards dissecting molecular routes of intercellular communication in the tumour microenvironment: phenotypic plasticity of stem cell-associated markers in co-culture (carcinoma cell/fibroblast) systems.

Increasing evidence attributes tumour fates to a small population of cells (cancer stem cells) capable of surviving therapeutic interventions. Investigation of their characteristics, especially in cross-talk with other cell types of the tumour microenvironment, can pave the way to innovative therapeutic concepts. The central issue of this study was to evaluate the impact of stroma on tumour cells with stem cell-like features in a squamous cell carcinoma model (FaDu). Six different types of experimental conditions were tested using distinct compositions of the culture system, and both morphologic and molecular features of the tumour cells were analysed. In detail, FaDu cells alone were used as a control, compared to tumour cells from co-culture, with squamous cell cancer-derived stromal fibroblasts or normal skin human fibroblasts, both in the direct and indirect (insert) systems, adding analysis of side population cells of FaDu culture. Measurements were taken on days 2, 7 and 9 of culture and immediately after preparation in the case of the side population. A panel of antibodies against keratins 8, 10, 19, stem cell markers CD29, CD44, CD133, as well as biotinylated adhesion/growth-regulatory galectin 1 served as a toolbox for phenotypic characterization. Co-culture with fibroblasts prepared from tumour stroma and with dermal fibroblasts affected marker presentation, maintaining an undifferentiated stage phenotypically related to stem cells. Side-population cells showed close relationship to cancer stem cells in these characteristics. In conclusion, normal and tumour stromal fibroblasts are capable of shifting the marker expression profile of FaDu cells to a stem cell-like phenotypic pattern in co-culture.

Microscopic notes on the perinucleolar chromatin region in immature and mature human B-leukemia lymphocytes.

Perinucleolar region was studied in lymphocytes of patients suffering from chronic B lymphocytic leukemia to provide more information on the perinucleolar-condensed chromatin - heterochromatin - during the maturation of these cells. The perinucleolar heterochromatin of lymphocytes in smear preparations was visualized using a simple, but sensitive cytochemical method for the demonstration of DNA. The perinucleolar heterochromatin was also easily visible as unstained perinucleolar regions in specimens stained for RNA. In addition, the perinucleolar heterochromatin of lymphocytes was distinct and apparent in the transmission electron microscope using conventional as well as cytochemical methods for visualization of chromatin structures. Despite the great variability, the maturation of leukemic lymphocytes was accompanied by an increased width of the perinucleolar heterochromatin shell. It seems to be also interesting that the perinucleolar region of both immature as well as mature leukemia lymphocytes contains heterochromatin bodies about 2µm in diameter. They appeared to be a regular component of the perinucleolar heterochromatin shell and were apparently different from other nuclear bodies present at the nucleolus. In contrary to other known nuclear bodies, perinucleolar heterochromatin bodies in leukemia lymphocytes consisted only of conglomerates of DNA containing chromatin fibrils and did not contain other structural components including RNA. The presence of perinucleolar heterochromatin bodies in the perinucleolar region of leukemia lymphocytes is not contradictory with the present knowledge on that nuclear territory. They might be associated with presumed special perinucleolar DNA loci, which according some previous studies were more expressed in malignant cells.

Phylogeny, regeneration, ageing and cancer: role of microenvironment and possibility of its therapeutic manipulation.

Data about the possible correlation between reduction of the regeneration capacity in the course of phylogeny and formation of malignant tumours have been summarized from invertebrates to mammals. The evolutionarily increasing complexity of body building plane and expectancy of longevity in the course of phylogeny seems to be grossly negatively correlated with diminished regeneration capacity, but positively with increased occurrence of malignant tumours. A certain evolution-based switch-off mechanism reducing the extent of regeneration in developmentally complicated and long-living animals such as mammals and birds can be hypothesized and benefits of loss of this ability are discussed. This high incidence of malignancies seems to be related, in addition to other factors, to prolonged and cumulative exposure to cancerogenic stimuli in the course of lifetime. Longevity, supported by the progress and availability of medical care to the population, has been unveiling this phenomenon during recent decades. From this point of view, ageing represents the main risk for cancer acquisition. The probable role of microenvironment in all the discussed phenomena such as healing/regeneration, inflammation, and cancer is discussed and targeting of microenvironment is consequently predicted as a possible therapeutic target where controlled manipulation may represent a new approach to the treatment of cancer patients.

Comparative analysis of IL-8 and CXCL-1 production by normal and cancer stromal fibroblasts.

It has been shown that fibroblasts within the stroma of malignant tumours can affect the tumour's biological character, influencing such properties as local aggressiveness and metastasis potential. This influence is asserted via paracrine secretion of multiple cell factors, including chemokines. This study demonstrates that both normal keratinocytes and cancer cells can stimulate the secretion of chemokines IL-8 and CXCL-1 from normal dermal fibroblasts and stromal fibroblasts from squamous cell carcinoma. The effect of epithelia on normal fibroblasts leads to a transient secretory change, in contrast to stromal fibroblasts which generate a more prolonged one. This observation demonstrates that stimulated expression of both IL-8 and CXCL-1 is not specific to cancer, supporting the hypothesis that similar mechanisms exist between wound healing and oncogenesis. It also shows that stromal fibroblasts isolated from a tumour have significantly different features from normal fibroblasts.

The Reduction of the Cell Nuclear Size in the Cell Body Space During the Differentiation Might Be Cell Lineage Specific (A Retrospective Morphological Note).

The cell body space occupied by the nucleus decreased during the cell differentiation of the granulocytic cell lineage in CML (Chronic Myeloid Leukemia) patients. In contrary, in patients suffering from CLL (Chronic Lymphocytic Leukemia), the cell body space occupied by the nucleus during the cell differentiation of the lymphocytic lineage did not decrease despite the reduction of the cell size. Thus, the cell body space occupied by the cell nucleus during the differentiation was characteristic for each of these cell lineages.

Fibroblasts prepared from different types of malignant tumors stimulate expression of luminal marker keratin 8 in the EM-G3 breast cancer cell line.

It is widely recognized that stromal fibroblasts significantly influence biological properties of multiple tumors including breast cancer. However, these epithelial-mesenchymal interactions seem to be essential in tumor biology and it is not fully clear whether this interaction is tumor type-specific or has a more general non-specific character. To elucidate this question, we tested the effect of cancer-associated fibroblasts (CAFs) isolated from different types of tumors (breast cancer skin metastasis, cutaneous basal cell carcinoma and melanoma, squamous cell carcinoma arising from oral cavity mucous membrane) on the EM-G3 breast cancer cell line. The results were compared with control experiments using normal human dermal fibroblasts, 3T3 mouse fibroblasts, and 3T3 fibroblasts influenced by the fibroblasts prepared from the basal cell carcinoma. Our results demonstrated that expression of luminal marker keratin 8 was influenced only by CAFs prepared from any tested tumors. In contrast, all tested types of fibroblasts showed a strong stimulatory effect on the expression of basal/myoepithelial marker keratin 14. The CAFs also elevated the number of cells with positivity for both keratins 8 and 14 that are similar to ductal originated precursor cells. The expression of proliferation marker Ki67 was not influenced by any of the tested fibroblasts. In conclusion, our data indicate that CAFs are able to influence the phenotype of a breast cancer cell line and this effect is based on a tumor type-unspecific mechanism. Finally, a clear functional difference between normal and CAFs was demonstrated.

Early stages of trachea healing process: (immuno/lectin) histochemical monitoring of selected markers and adhesion/growth-regulatory endogenous lectins.

Tracheotomy may be associated with numerous acute and chronic complications including extensive formation of granulation tissue. The emerging functional versatility of the adhesion/growth-regulatory galectins prompted us to perform a histochemical study of wound healing using rat trachea as model. By using non-cross-reactive antibodies and the labelled tissue lectins we addressed the issue of the presence and regulation of galectin reactivity during trachea wound healing. Beside localization of high-molecular-weight keratin, wide-spectrum cytokeratin, keratins 10 and 14, α-smooth muscle actin, vimentin, fibronectin, and Sox-2, galectins -1, -2, and -3 and their reactivity profiles were measured in frozen sections of wounded and control trachea specimens 7, 14, and 28 days after trauma. A clear trend for decreased galectin-1 presence and increased reactivity for galectin-1 was revealed from day 7 to day 28. Sox-2-positive cells were present after seven days and found in the wound bed. Interestingly, several similarities were observed in comparison to skin wound healing including regulation of galectin-1 parameters.

Heterochromatin condensation in central and peripheral nuclear regions of maturing lymphocytes in the peripheral blood of patients suffering from B chronic lymphocytic leukemia - a cytochemical study.

The present study was undertaken to provide complementary information on heterochromatin condensation in central and peripheral nuclear regions during maturation of human leukemic lymphocytes using simple image processing and DNA image densitometry at the single cell level. Such approach indicated that the heterochromatin condensation in perinucleolar and extranucleolar "gene rich" central nucleolar regions preceded that in the "gene poor" nuclear periphery at the nuclear membrane. Thus, the maturation of lymphocytes was accompanied by a marked increase of the heterochromatin condensation at the nuclear membrane that reflected the maturity of these cells. In addition, in contrary to the nuclear size, no substantial differences of the heterochromatin condensation in central and peripheral nuclear regions were noted between untreated and treated patients with cytostatic therapy at the time of taking samples for the present study. On the other hand, the larger heterochromatin condensation in central nuclear regions occasionally persisted in small mature lymphocytes of all studied patients. Such phenomenon might represent the return to the cell cycle or a further type of maturation asynchrony that in leukemic cells is not exceptional.

Heterochromatin density (condensation) during cell differentiation and maturation using the human granulocytic lineage of chronic myeloid leukaemia as a convenient model.

The present study was undertaken to provide complementary data on the heterochromatin condensation in both central and peripheral nuclear regions during the cell differentiation and maturation using computer-assisted density measurements at the single-cell level. The lineage of neutrophilic granulocytes in the bone marrow of patients suffering from chronic myeloid leukaemia was very convenient for such study because the increased number of granulocytes in all developmental stages was satisfactory for heterochromatin density measurements. The morphology of leukaemic and non-leukaemic neutrophilic granulocytes is similar and each differentiation or maturation stage is easily identified. A markedly increasing heterochromatin density--condensation--in the peripheral nuclear region at the nuclear envelope accompanied both the differentiation and maturation of these cells. Thus, peripheral chromosomal territories at the nuclear envelope are important for both the differentiation and maturation process. In contrast, the heterochromatin density of nuclear central regions was already high in early differentiation stages and exhibited a less distinct increase during the differentiation, but was more apparent in late maturation stages representing the terminal differentiation. A limited number of maturing cells with persisting large heterochromatin density in central nuclear regions without markedly increased heterochromatin condensation at the nuclear periphery might represent a further maturation abnormality--asynchrony--during the granulocytic development. From the methodological point of view, both, the cytochemical method for the DNA demonstration and the panoptic May-Grünwald-Giemsa staining, are convenient for computer-assisted chromatin densitometry at the single-cell level.

Comparative analysis of the nuclear presence of adhesion/growth-regulatory galectins and reactivity in the nuclei of interphasic and mitotic cells.

Nuclear galectins participate in splicing of pre-mRNA. In this study we detected galectins-1, -2, -3 and -7 and their glycoligands in three types of cells: fibroblasts, cancer epithelial cells and melanoma cells. The results demonstrated that the nuclear expression of distinct types of galectins and their ligands in interphasic nuclei is dependent on the cell type. The extensive binding of labelled galectins-1 and -2 to mitotic cells (around chromosomes, in mitotic spindle and in bridge connecting both daughter cells) suggests their role during the cell division.

Pediatric Inflammatory Multisystem Syndrome (PIMS) - Potential role for cytokines such Is IL-6.

COVID-19 is a transmissible respiratory disease caused by coronavirus SARS-CoV-2, which is similar to SARS or MERS. Its increased severity was noted in aged patients usually over 65 years of age. Children and young people have an asymptomatic or mild course of the disease.Unfortunately, the number of children with problems after mild or asymptomatic COVID-19 recovery is increasing and their troubles resemble Kawasaki disease, although the laboratory findings seem to be different. This condition is called pediatric inflammatory multisystem syndrome (PIMS), and it is a new disease seen in children directly influenced by previous SARS-CoV-2 infection. The literature reports that PIMS typically follows 2-4 weeks after SARS-CoV-2 infection. The clinical symptoms of the affected children are extremely complex, ranging from gastrointestinal to cardiovascular problems with frequent skin and mucosal manifestations, and without intensive treatment they can be fatal. The exact causes of PIMS are recently unknown, however, it is explained as hyperactivation of immunity.In this minireview, we summarize data on the prominent role of the IL-6-IL-6R-STAT3 axis in PIMS aetiopathogenesis. Therapeutic manipulation of IL-6 or IL-6 receptor could be an approach to the treatment of children with severe PIMS.