Level Of Cellular Differentiation Research Articles

Correlation between histological grade and positron emission tomography parameters in cervical carcinoma.

The aim of the present study was to evaluate the changes in cervical cancer glucose metabolism for different levels of cellular differentiation. The metabolic activity was measured by standardized uptake value (SUV), SUV normalized to lean body mass, metabolic tumor volume and total lesion glycolysis using fluorine-18 fluorodeoxyglucose positron emission tomography (PET). A correlation study of these values could be used to facilitate therapeutic choice and to improve clinical practice and outcome. This study considered 32 patients with diagnosed cervical cancers, at different International Federation of Gynecology and Obstetrics stages. Glucose metabolism was assessed by PET examination, and histological specimens were examined to determine their initial grade of differentiation. A correlation study of these values was evaluated. Histological examination showed that all cases were of squamous cell carcinoma. Regarding the differentiation of the tumor, 19 well- to moderately-differentiated tumors and 13 poorly-differentiated tumors were determined. Negative findings for correlations between metabolic parameters and initial grade of histological differentiation were found, and considering that histological grade has been shown to have no consistent prognostic value in cervical cancer treatment, PET imaging could play a significant role in cervical cancer prognosis.

Aquaporin 5 Expression and Its Relationship to Apoptosis in Different Grades of Differentiated Non-Small Cell Lung Carcinoma

Aquaporin 5 has been recently found as an important oncogenic marker whose expression levels seem to be determined by the level of cellular differentiation. Despite aquaporin volume decrease (AVD) being the most conserved earliest event in apoptosis, there is still a paucity of studies exploring on aquaporin expression and its relationship with apoptosis in cancer. The aim of this study was to investigate the expression of aquaporin 5 channel protein and to explore on its relationship with apoptosis in well and poorly differentiated non-small cell lung carcinoma both in-vivo and in-vitro. Findings from the study showed that the expression of AQP5 both in-vivo and in-vitro was dependent on the type and degree of tumour differentiation. In-vivo, an increase in aquaporin 5 expression was associated with an increased apoptosis in both poorly and highly differentiated adenocarcinoma (AC) while there was no association between aquaporin 5 expression and apoptosis in both poorly and highly differentiated squamous cell carcinoma (SCC). In vitro, differentiation therapy in the form of ATRA decreased both cell proliferation and increased the expression of AQP5 in A549 cells. The cytomorphological changes, expression of differentiation markers and flow cytometry apoptotic results were dependent on the dose of ATRA treatment. In conclusion, a higher expression of aquaporin 5 was found to promote the rate of the apoptotic process in lung adenocarcinoma (AC).

Transgenic studies for modulating terpenoid indole alkaloids pathway in Catharanthus roseus: present status and future options

The anti-neoplastic herb Catharanthus roseus (Madagascar periwinkle; Family Apocynaceae), known to harbor >130 bioactive terpenoid indole alkaloids (TIAs), is in global attention of transgenic research for pathway engineering. This medicinal herb has a long folklore history of its usage in the treatment of several health disorders owing to the presence of a variety of secondary metabolites, particularly the alkaloids, phenolics and anthocyanins. Among its various bioactive molecules, C. roseus is most valued for being the exclusive bio-resource of two of the most effective anti-cancerous drugs—vincristine and vinblastine that are indispensible components of several modern day chemotherapeutic regimens. The in-planta yields of these bioactive TIAs are extremely low (<0.0002 %) owing to very rigid developmental, genetical and environmental regulation controls as a part of plant’s own auto-protection strategies against these cytotoxic molecules. Consequently the high cost of production coupled with increasing market demand for these alkaloidal drugs have made TIAs pathway as one of the preferred target for plant metabolic engineering efforts to boost their commercial production. The transgenic approaches so far applied in C. roseus can be grouped into three major lines of investigations. The first line of efforts have been dominated by the genetic transformation studies carried out with wild type Ti or Ri plasmids to measure the influence of their random insertion on TIAs biogenesis. These studies, besides helping the optimization of basic transformation protocols at different levels of cellular differentiation, have largely contributed towards the better resolution and expression of TIAs pathway architecture at the level of associated genes and enzymes. Second line of metabolic engineering works is being centered around the efforts on preparation of genomic libraries and genome mapping to hunt for TIAs pathway genes and associated transcription regulators/factors, followed by their cloning, insertion and hyper-expression to modulate the carbon flux towards desired end products. Modern day transgenic attempts in C. roseus are largely focused on superimposing the concurrent influences of biotic and abiotic elicitation, T-DNA activation and RNAi or virus induced gene silencing approaches for higher TIAs biogenesis. The pace of transgenic research in C. roseus in last two decade has been rapid and demands periodic compilation and reviewing of published literature to provide a handy status up-date of the subject. The present compilation is an effort in this direction and intends to provide a state-of-art account of various transgenic approaches currently being pursued in this high value herb. More than 130 research papers have appeared on various aspects of transgenic cells, tissues and plant production in C. roseus in 30 years. The bulk of these efforts (64.96 %) were made at the level of Agrobacterium rhizogenes-mediated hairy root cultures, followed by 26.80 % in A. tumefaciens-mediated transformed tissues and 8.24 % in cells/tissue cultures subjected to particle bombardment approach. In the present compilation, these studies are further grouped into specific categories wherein over-expression of TIAs pathway specific genes, transcriptional factor regulation, elicitation/stress superimposition, transgenic plant regeneration, metabolites profiling and gene silencing etc. were investigated in different transformed tissue.

Systems biology of lung development and regeneration: current knowledge and recommendations for future research

The lung begins as a simple outpouching of the foregut and develops by stages into a highly complex organ, the proper function of which is essential to life for terrestrial mammals. Interruption of normal lung development can result in death or chronic disease. Conversely, repair after lung injury, as well as many acquired diseases, involves recapitulation, often aberrant, of developmental pathways. The principal paradigms in lung development are branching morphogenesis and alveolar septation, but others, such as vasculogenesis, are critical. These are partially understood at the level of cellular differentiation and molecular signaling, but a true systems biology analysis of lung development and lung repair/regeneration, including bioinformatics analysis and integration of data from unbiased and complementary '-omics' level studies, is still lacking. The past decade has seen increasing numbers of genomic, proteomic, metabolomics, and epigenomic studies of lung development and lung remodeling. In many cases, these studies have confirmed the importance of pathways uncovered painstakingly through single-molecule approaches, but they have also uncovered novel and unexpected pathways and new paradigms such as noncoding RNA. Future studies will need to combine data from multiple repositories and apply novel mathematical and computational models in order to establish a systems-level understanding of this remarkable organ.

In Vitro Cell Culture Infectivity Assay for Human Noroviruses

Human noroviruses cause severe, self-limiting gastroenteritis that typically lasts 24-48 hours. Because of the lack of suitable tissue culture or animal models, the true nature of norovirus pathogenesis remains unknown. We show, for the first time, that noroviruses can infect and replicate in a physiologically relevant 3-dimensional (3-D), organoid model of human small intestinal epithelium. This level of cellular differentiation was achieved by growing the cells on porous collagen-I coated microcarrier beads under conditions of physiological fluid shear in rotating wall vessel bioreactors. Microscopy, PCR, and fluorescent in situ hybridization provided evidence of norovirus infection. Cytopathic effect and norovirus RNA were detected at each of the 5 cell passages for genogroup I and II viruses. Our results demonstrate that the highly differentiated 3-D cell culture model can support the natural growth of human noroviruses, whereas previous attempts that used differentiated monolayer cultures failed.

Differential effects of transforming growth factor-beta1 on cellular proliferation in the developing prostate.

TGFbeta1 plays an important role in the growth of the prostate and has been reported to stimulate or inhibit the proliferation of prostatic epithelia. We show here that Tgfbeta1, Tgfbeta2, and Tgfbeta3 mRNA expression correlated with developmental growth of the prostate. Recombinant TGFbeta1 inhibited the growth of the prostate when added to cultures of ventral prostate (VP) organs grown in vitro. Interestingly, TGFbeta1 had contrasting effects on cellular proliferation; it stimulated proliferation at the periphery of the organs (distal to urethra), but inhibited proliferation in the center of the organs (proximal to urethra). We speculate that differential effects on proliferation may be determined by the level of cellular differentiation, because cells at the periphery are undifferentiated whereas those in the center are more highly differentiated. TGFbeta1 also stimulated branching morphogenesis at growing ductal tips at the perimeter of the VP. To investigate potential mechanisms of TGFbeta1 action, we examined the three-dimensional distribution of smooth muscle in prostatic organs after treatment with TGFbeta1. TGFbeta1 showed a significant effect on the distribution of smooth muscle within VPs, which may mediate part of its effect on proliferation. Finally, we addressed how testosterone and TGFbeta1 might affect gene expression in our developmental system. Testosterone repressed the expression of Tgfbeta2 mRNA in the prostate, whereas TGFbeta1 showed a modest repression of fibroblast growth factor-10 mRNA. It appeared that the effects of these factors were more pronounced in a model of prostatic mesenchyme devoid of epithelia than in prostatic organs (containing epithelia).

Pancreatic reg gene expression is inhibited during cellular differentiation.

Factors that control pancreatic regenerating (reg I) gene expression are unknown, but it is believed that its expression may correspond with cellular differentiation. The authors recently demonstrated that reg I is expressed in AR42J, a rat acinar cell line whose state of differentiation can be modulated by dexamethasone. They used this line to study reg I expression during cellular proliferation and differentiation. After treatment of cells with 10 nmol/L dexamethasone, proliferation was assayed by thymidine incorporation; differentiation by expression of elastase I mRNA. Reg I mRNA levels were measured using a rat reg I cDNA probe, and reg I protein levels assayed by enzyme-linked immunosorbent assay of cellular lysates with a polyclonal antibody. The effect of gastrin, cholecystokinin and glucagon on reg I expression was also studied. When compared with controls, treatment with dexamethasone caused thymidine incorporation to decrease and elastase mRNA levels to increase. Reg I mRNA decreased from controls of 100 +/- 16% to 40 +/- 18% (p < 0.05), and reg I protein levels decreased as well. Gastrointestinal hormones had no significant effect on either elastase or reg I gene expression. Expression of reg I inversely correlates with the level of cellular differentiation, can be modulated via the glucocorticoid receptor, and is a potential marker of gastrointestinal epithelial differentiation. Despite its presence within a pancreatic acinar cell line, reg I gene expression is not modulated by gastrointestinal hormones.

Cellular localisation of tumour antigen (TA-4) in normal, dysplastic and neoplastic squamous epithelia of the upper aerodigestive tract

We report the use of tumour antigen (TA-4) polyclonal antiserum to assess the level and pattern of TA-4 antigen expression in formalin-fixed paraffin-embedded tissue sections from 110 patients with a range of normal, dysplastic and malignant squamous epithelia from various sites in the upper aerodigestive tract. There was a high degree of TA-4 antigen expression in the superficial layers of normal squamous epithelium and in well-differentiated squamous cell cancers (SCC). TA-4 expression was consistently absent in dysplastic oral squamous epithelium and in poorly differentiated SCCs. The degree of cellular heterogeneity in moderately differentiated SCCs was such that morphologically identical squamous cancer cells could be distinguished on the basis of TA-4 expression. Immuno-electron microscopy localised TA-4 antigen to tonofibrils in both normal buccal (squamous) cells and in squamous cancer cells. Results of Western blotting confirmed the presence of a 48 kDa protein consistent with TA-4 antigen in both SCCs and in normal buccal mucosa. We conclude that TA-4 protein is a normal cellular component, that cellular TA-4 expression is related to the level of cellular differentiation in squamous epithelia and that it is not likely to be useful as an independent index of cellular proliferation or malignant behaviour.

Blood group substances as differentiation markers in human dento‐gingival epithelium

The level of cellular differentiation of human oral, sulcular, and junctional epithelium was compared by immunohistochemical analysis of cell membrane‐associated blood group‐specific carbohydrates. Identification of the blood group A‐specific carbohydrate and its two immediate precursor substances, type 2 chain H and N‐acetyllactosamine, was accomplished by an indirect immunofluorescence technique. Murine monoclonal antibodies reacting specifically with the antigenic determinants of the blood group substances were used as markers. The blood group A substance, indicating the highest level of cellular differentiation, was demonstrated on the cells in the upper layers of the oral epithelium. In the sulcular epithelium, the A substance was present on a few cells only, while type 2 chain H was observed frequently. This indicates an intermediate differentiation level of sulcular epithelium. The type 2 chain H precursor, N‐acetyllactosamine, the indicator of the lowest level of cell differentiation among the tested substances, was the only blood group substance detected on the junctional epithelial cells and on the basal cells of the sulcular and oral epithelium. Based upon previous studies of cell renewal and differentiation in oral epithelium, the present results indicate that the variations in distribution of the different blood group substances correspond with the regional rates of cell division and the levels of cellular differentiation. The findings also suggest that the cells in the junctional epithelium differentiate to a level similar to that of basal cells in the oral epithelium.

On the fine structure of the skin of larval, juvenile and adult Ichthyophis (Amphibia, Caecilia)

The skin of a number of larvae at different developmental stages (in part determined by the level of differentiation of a variety of skin components), of a juvenile 9–10 cm specimen and of adults of Ichthyophis was examined by electron microscopy. More important results include descriptions of (a) the larval Leydig cells and their differentiation; (b) the fully developed Merkel cells and their synaptic association in older larvae and the postmetamorphic forms; (c) the structure and arrangement of the postmetamorphic flask cells and their associated nerves in the epidermis; (d) the relatively early development and differentiation of the mucous and granular glands in the dermis of the larva, comparable with those of adults; (e) the presence of iridophores in the dermis of the juvenile specimen and their relationship with the laminophore type cells. Some comparisons are made with previous descriptions of young larval and adult skin of Ichthyophis. The level of cellular differentiation of Leydig cells, Merkel cells and the glands would imply that they were fully functional in older premetamorphic larvae of Ichthyophis: indeed these components are recognizable, albeit in immature form, in young larvae 4.5 cm long.

Swine lymphoid and myeloid neoplasms in Italy.

In the decade 1973-1982, data from all the principal diagnostic centers in Italy reveals that swine lymphoid and myeloid neoplasms (LMN) have been observed only few times (78 cases). In a 25-year period (1950-1984) 48 cases were diagnosed in our Institute, among which all the known forms of LMN, including the most uncommon such as multiple myeloma (1) and myeloid forms (4) including 1 chloroma and 1 erythraemic neoplasm. The incidence remains low; 1.17% of the diseased swine sent for necropsy, with no significant increase during the years. In the same period the incidence of other neoplasms was 1.14%. Also the data from the abattoir of Bologna confirm a low incidence: in the last 2 years lymphoid neoplasms were observed only twice among 130,000 slaughtered pigs (15 cases per million). This incidence is therefore similar to that noticed in slaughterhouses in other European countries and in the U.S.A. As for the anatomohistopathological features, lymphosarcoma presents a constant autochthonous production of immature collagen fibrils, but the degree of this production has no significant relation with either the macroscopic type of lesions, nodular or infiltrating (diffuse), or the level of cellular differentiation. Diffusely haemorrhagic lesions were observed in a relatively high percentage (14%) of lymphosarcomas. The incidence of myeloid neoplasms is relatively high compared with that of lymphosarcomas: from 5% of Italian cases as a whole to 14% of the cases studied in our Institute. This confirms that the pig is second to the dog as a domestic animal showing most of these myeloid neoplasms.

Prospects and problems in the large scale production of metabolites from plant cell tissue cultures

AbstractA wide range of plant products can be made directly by using plant cell tissue cultures. However, the economic production of even highvalue products from such cultures has not been conclusively demonstrated. One problem is that rapid growth and high product yields often appear to be mutually exclusive with plant cell tissue cultures. Some level of cellular differentiation often is required for the expression of genes associated with product formation; only unorganized cells grow rapidly. Another problem results from the tendency of plant cells to form aggregates, which leads to a mixture of cell types in culture. The biological response is a function not only of the chemical environment but also the physical (e.g. hydrodynamic) environment which makes scale‐up of suspension processes difficult. In addition, cell lysis due to high liquid shear is a significant design constraint. Some of these problems can be circumvented by using multi‐stage continuous culture devices or with immobilized cell reactors. Emphasis will be on membrane entrapped cultures.

Participation of hematopoietic stem cells in formation of the immune response

A quantitative ultrastructural investigation of cancer in mice mammary glands and of its metastases to the lungs was carried out. It was established that in tumors showing no metastatic spreading in experiment the area of membrane surface of the endoplasmic reticulum and the number of bound ribosomes are greater than those in tumor spreading metastases. At the same time the number of ribosomes organized into polysomes is higher in the metastasized tumors. The comparison of the tumors with their metastases revealed differences in the structure of the mitochondrial apparatus: the surface area of cristae is larger in the metastatic foci. The evidence obtained shows that tumors spreading metastases have a lower level of cellular differentiation. The primary and metastatic foci do not exhibit any difference in the level of differentiation.

I Lomasomi: Loro Probabili Rapporti con la Crescita per Distensione della Parete Cellulare

Abstract « Lomasomes »: their probable role in the expansion growth of the cell wall. — It was previously reported that lomasomes are present in higher plant cells. In a preliminary comunication Authors described the morfological characteristics of the lomasomes and their position in the cell. It was shown that lomasomes vary in organization which appears to be granular or vescicular and in distribution along the cell wall. Both these characters seemed directly related with the level of cellular differentiation. In this paper it has been reported that the number of lomasomes per cell was sharply decreased when Avena Coleoptiles were illuminated per 3 hours. During this period of time also the growth of the Coleoptiles was inhibited about 8%. These data seem favorable to the hypothesis that lomasomes are tigtly involved in the mechanisms controlling the expansion growth of the cell wall.

The eye-pigmentary system ofDrosophila

This investigation was mainly directed at the solution of the problem of the multiplicity of eye-colour genes inDrosophila melanogaster. 1. For the purposes of routine quantitative comparison of the red and brown eye pigments of different mutant strains with those of the wild-type, methods are described for the rearing of normal-sized flies and for the extraction of the two pigments and their spectrophotometric analysis. The light-absorption curves are given of these pigments in the wild-type and various mutants, singly and in combination. The two pigments typical of the wild-type are found in all mutants with the exception of the alleles of the white locus which condition the production of a qualitatively changed red pigment. 2. Quantitative estimations of the pigments in the wild-type and the different mutants studied indicate the following effects of mutant genes:wm4 has decreased amounts of both pigments, with the red pigment content varying greatly with temperature changes;ras2 has a decreased amount of red pigment; the genes of the ruby group,rb, cm, g3 andcar, effect a reduction in the content of both pigments, but there is no simple relation between the amounts of this reduction, the four genes showing differential effects on the two pigments; the alleles ofw reduce the amount of red pigment to a great extent and the brown pigment content to a varying extent for the different alleles, but again the effects on the two pigments are differential, there being no simple linear quantitative ratio between the amounts in the different alleles;st suppresses the production of the brown pigment but possibly causes an increase in red pigment content;bw suppresses the production of the red pigment (unless a small amount of qualitatively changed red pigment is formed) and also reduces the brown pigment content; combinations between the genes of the ruby group,inter se and withst andbw, show sub-additive interaction effects and an overlapping in the mode of their action; two alleles ofcar show a simple quantitative relation in the amount of red pigment produced. 3. A scheme is presented to show some of the interrelationships which exist between the various genes which affect eye pigmentation. The probable mode of action of the normal allele of white is at the level where a common substrate is differentiated for the formation of specific substrates for the red and brown chromogens, but where also certain by-products are formed for utilization in the protein carrier and granule system. The normal alleles of scarlet and brown then fit into the scheme at a later level, i.e. that of chromophore or chromoprotein formation. The action of the normal allele of raspberry2 seems to be at the level of cellular differentiation. In connexion with the mode of action of the normal alleles of the genes for ruby, carmine, garnet3 and carnation the concept is developed that many eye-colour genes affect eye pigmentation only indirectly, i.e. eye colour is influenced by them epigenetically, consequent on their main function being the directing of enzyme specificities for the breakdown and resynthesis of proteins during metamorphosis; the products of breakdown are utilized in the eye-pigmentary system which in this activity is partly an excretory system.