Transformation of tracheal epithelium exposed in vitro to N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)

Using an organ culture/cell culture system, we transformed rat tracheal epithelial cells in vitro by exposure to MNNG. Ten tracheal organ cultures per group were exposed twice (at days 3 and 6) to 0,0.001, 1.0 or 10.0 microgram MNNG/ml of medium. Following this exposure, the explants were placed on the bottom of culture dishes to initiate epithelial cell outgrowths and establish primary cultures. Each explant was replanted 8-10 times to produce multiple outgrowths. The number of primary cultures and the number of subsequently established cell lines obtained was carcinogen-dose-dependent. The average number of primary epithelial cell cultures per explant after exposure to 0, 0.001 1.0 and 10.0 microgram MNNG/ml was 1.3, 1.5, 3.3, and 4.6, respectively. The average yield of cell lines per explant in these groups was 0, 0.8, 1.3, and 2.0, respectively. It is apparent that cell lines could only be established from carcinogen-exposed epithelium. These cell lines are currently being tested for tumorigenicity in vivo. To date, of 35 cell lines tested between the 5th and 15th passages, 5 cell lines from the 10 microgram MNNG/ml group and 2 from the 1.0 microgram MNNG/ml group have produced palpable tumors upon injection into immunosuppressed recipients.     

Pulmonary carcinoid tumors is tissue and organ culture

Pulmonary carcinoid tumors arise from cells whose function is yet to be defined. Conditions for maintenance of cells of these tumors for prolonged periods of time in tissue and organ cultures were established in order to gain insight into their supposed endocrine activity. We succeeded in growing explants of these tumors in organ culture for as long as 5 months without the cells losing their ability to produce large numbers of neurosecretory-type granules.     

Mouse lung epithelial cell lines--tools for the study of differentiation and the neoplastic phenotype

Several dozen lung epithelial cell lines have been established in culture over the past 20 years from normal lung explants and their spontaneous transformants, and from lung tumors that arose spontaneously or were induced with chemicals, viruses, or oncogenic transgenes. To provide information from which to choose appropriate lines for investigating problems in lung cell biology and pulmonary neoplasia, this review describes the origins of these lines and some of their characteristics. These include growth, morphology, tumorigenicity, ability to metastasize, xenobiotic metabolism, mutational status, signal transducing activities, cytogenetics, ability to form domes, and electric conductance. In addition to collecting this information in a single place for the first time, we describe previously unpublished apoptosis features of some of these lines. An increasing number of investigations are beginning to use these lines and this review contains references into 1997.     

Cranial MRI in the patients with chronic liver disease (CLD)

Doxorubicin shows a wide spectrum of activities in solid tumors, especially against breast carcinoma. The aim of this study was to examine if doxorubicin, when given at lower concentrations than applied in clinic, may induce changes in treated cells. With this purpose we developed human breast adenocarcinoma SK-BR-3 cell line resistant to doxorubicin. The sensitivity of these cells to doxorubicin and to some other cytostatics used in cancer treatment was determined by colorimetric MTT assay. Some parameters which may be of importance as prognostic factors in treatment of breast cancer were analyzed as well. The expression of genes involved in mitotic signal pathway (EGF, TGF alpha, EGF-R, erbB-2, erbB-3, c-myc and c-H-ras) was determined immunocytochemically. The concentrations of cathepsins were determined using quantitative immunoreactive assays (cathepsins B and L) or immunoradiometric assay (cathepsin D). The results revealed that even low doses of doxorubicin can induce numerous changes in treated cells: they become resistant to doxorubicin, and cross-resistant to several other cytostatics. The expression of the above mentioned genes involved in mitotic signal transduction, as well as cathepsins D and L, was similar in both parental and doxorubicin treated cells.     

Morphology and growth characteristics of epithelial cells from classic Wilms' tumors

The ability to establish cell cultures representing the epithelial component of Wilms' tumor was determined for 18 cases of classic Wilms' tumors. From these 18 cases only two resulted in the culture of epithelial cells. Although the tumors from both cases were composed of a prominent epithelial component, other classic tumors not producing epithelial cell cultures also possessed appreciable epithelial components. Likewise, heterotransplants of these two primary tumors failed to give rise to epithelial cell cultures, although cultures of the blastemal element were produced. This suggests that Wilms' tumors may be prone to differentiate in different directions at varying times during tumor growth, possibly dependent on local tumor environment. Epithelial cells from these two classic cases were grown in culture in basal medium composed of a 1:1 mixture of Dulbecco's modified Eagle's medium and Ham's F-12 medium, supplemented with selenium, insulin, transferrin, hydrocortisone, tri-iodothyronine, and epidermal growth factor, on a collagen type I matrix with absorbed fetal calf serum proteins. One of the two cases also required the addition of bovine pituitary extract, ethanolamine, prostaglandin E1, and putrescine for optimum growth. Morphological analysis disclosed that the cultured cells were very similar to normal renal tubular cells in culture, except that the cells displayed little evidence for differentiated active ion transport and tended to grow in a multilayered arrangement. The culture of the epithelial cells from classic Wilms' tumors provides a model system for the study of tumor differentiation and progression.     

all-trans-retinoic acid preserves viability of fibroblasts and keratinocytes in full-thickness human skin and fibroblasts in isolated dermis in organ culture

Human dermal fibroblast and human epidermal keratinocyte survival was examined under various conditions in organ culture. Using cell recovery from organ-cultured tissue as the criterion, it was observed that no keratinocytes and few fibroblasts survived incubation for 10-12 days in serum-free basal medium containing a low level (0.15 mM) of extracellular Ca2+. Increasing the extracellular Ca2+ concentration to 1.4 mM or treating the tissue with 3 microM retinoic acid (RA) under low Ca2+ conditions resulted in increased keratinocyte and fibroblast survival; the two treatments together were more effective than either treatment alone. The same treatments preserved fibroblast survival when pieces of isolated dermal tissue were incubated in organ culture and also supported fibroblast survival in monolayer culture. These findings indicate that recovery of keratinocytes and fibroblasts from skin after maintenance in organ culture provides a simple but definitive measure of the viability of the major cellular elements present in the tissue. These findings suggest that RA treatment enhances survival of both fibroblasts and keratinocytes and that these effects of RA can be seen at physiological Ca2+ concentrations as well as at suboptimal levels of extracellular Ca2+. Finally, these results indicate that the dermis is a direct target of RA.     

Glycocoding as an information management system in embryonic development

The past 5 years have seen a burgeoning in the amount of data emerging from laboratories studying the early stages of embryogenesis. Much of this data implicates various aspects of glycobiology in the initiation and regulation of these processes. The level of analytical detail coming from these investigations has surpassed our ability to fully understand its overall significance within the context of the interactive/dynamic developmental process. This review proposes a pause in this seemingly endless quest for more detail so that we may take stock of our goals and objectives. The proposed goals include a mechanistic understanding of the process(es) involved in information managed at various 'transition points' during early embryogenesis, and an understanding of the mechanism(s) by which the spatial/temporal regulation of early development are managed. The 'transitions' which occur during cell to cell cluster, cell cluster to early organ architecture, and early organ architecture to functional organ development are fundamental and mirror the evolutionary process of biological information management. All of these 'transitions' involve increasing complexity, the development of hierarchies of information management systems (integrated bidirectionally), and spatial/temporal regulation which relies on historical events to map future structure and function. This review focuses on a relatively small number of studies which highlight these aspects of early development. A mechanism which involves glycocoding, an extension of the Roseman Hypothesis, and its direct use as an information management system is proposed and some supporting experimental evidence is presented. This extension of an existing hypothesis is related to several recent investigations, and is designed to broaden the experimental design of future studies so that these important process issues can be addressed.     

Introducing Gail Anderson, nee Rogers

From 1973 to May, 1996 585 kidney transplantations were performed in the Department of Transplantation. From 1983 to 1988 investigations on transplantation of pancreas islet cell culture were carried out. Because of financial difficulties these investigations had to be stopped. In 1992 a law was adopted which regulates organ removal for transplantation by the "option out" system. In 1996, a transplantation association of the Baltic countries, Balttransplant, which includes the Latvian Department, began to function. Work of this association in the field of transplantation coordination has lead to an increase of donor kidneys and improvement of graft quality. The center performs 14-16 transplantations of kidneys per 1 million of population every year. The patient one year survival rate is 87%, survival of transplants--72-75%. Further progress of transplantation in Latvia will be possible only if the economic conditions and progress in medicine in general improve.     

Development of T cell precursor activity in the murine fetal liver

The generation of T cell precursors in the liver of murine embryos was studied. The total number of T cell precursors in the liver was measured in thymic organ cultures by a limiting dilution assay. Sixty T cell precursors were detected in the liver at day 11 of gestation. By day 12 the number of precursors showed a 20-fold increase, half of which could be explained by in situ proliferation as ascertained by a fetal liver organ culture assay. By day 13 a further 2-3-fold increase was observed. Whereas the number of total liver cells continued to increase, that of T cell precursors declined in the following days, suggesting a massive exit of these cells after day 13. The capacity to generate a TCRB repertoire in the cells was evaluated by a PCR assay. T cell precursors in day 11 fetal liver developed a TCRB repertoire at day 8 of culture. The cells from days 12-15 developed an identically diverse repertoire by day 6, suggesting that day 11 precursors are more immature than those of later days. A mechanism for yielding a single wave of T cell precursors in the fetal liver is discussed with a proposed model.     

Phenotypic mapping of the chicken embryonic thymic microenvironment developing within an organ culture system

The chicken thymic microenvironment, as it developed in an embryonic thymus organ culture system, was phenotypically mapped using a panel of mAb defining both epithelial and nonepithelial stromal cell antigens. We have previously reported that thymocyte proliferation and differentiation with proceed for up to 6-8 days in thymus organ culture, hence demonstrating the functional integrity of the thymic microenvironment in vitro. During this time, the stromal component reflected that of the normal embryo with cortical and medullary epithelial areas readily identifiable by both morphology and surface-antigen expression. An abundance of subcapsular and cortical epithelial antigens was detected in the cultured thymus, particularly those normally expressed by the epithelium lining the capsule, trabeculae, and vascular regions (type I epithelium) in the adult and embryonic thymus. Medullary epithelial antigens developed in organ culture, although were present in lower frequency than observed in the age-matched embryonic thymus. MHC class II expression by both epithelial and nonepithelial cells was maintained at high levels throughout the culture period. With increasing time in culture, the ratio of epithelial to nonepithelial cells decreased, concurrent with a decrease in thymocyte frequency and suggestive of a bidirectional interaction between these two cell types. Thus, a functionally intact thymic microenvironment appears to be maintained in embryonic thymus organ culture, a model that is currently being exploited to assess the role of stromal antigens, as defined by our mAb, in the process of thymopoiesis.     

Defensiveness and perception of external inspiratory resistive loads in asthma

This paper introduces a model which incorporates fetal thymus organ culture (FTOC) from NOD mice to replicate thymic development of diabetogenic T cells. NOD fetal pancreas organ culture (FPOC) co-cultured with 13-16 day NOD FTOC for an additional 14-21 days produced less insulin than FPOC cultured alone. Insulin production from the FTOC of non-diabetic strains C57BL/6 and BALB/c was not inhibited by co-culture with FTOC from their syngeneic counterparts. Sections of the NOD co-cultures showed peri-islet infiltration with lymphocytes. Insulin reduction by FTOC/FP co-culture was prevented by co-culture of the NOD FT with FT from immunologically incompetent C.B-17 SCID/SCID mice. Co-culture of NOD FP with NOD FT prior to the development of T cells prevented generation of diabetogenic FTOC. Thus, early exposure of NOD T cell precursors to the thymic stromal elements of C.B-17 SCID/SCID FT or to islet antigens can negatively select for diabetogenic T cells or activate immuno-regulatory cells that can suppress diabetogenic T cell activity. The addition of blocking F(ab')2 fragments of anti-CD3epsilon monoclonal antibody to NOD FTOC/FP co-cultures prevented insulin reduction, implicating a role for TcR-mediated recognition in this "in vitro IDDM" model. The addition of activating whole anti-CD3epsilon caused the complete ablation of insulin production in FTOC/FP co-cultures from all strains tested. Transfer of unprimed syngeneic FTOC cells to prediabetic NOD mice prevented the onset of IDDM while transfer of islet-cell primed FTOC/FP cells slightly increased disease incidence. These data suggest that while diabetogenic T cells are present in the FT, they are normally suppressed, even after organ culture. However, these cells can induce the destruction of islet cells, in vitro and in vivo, if they are appropriately activated with pancreatic tissue.     

Characteristics of rare ovarian tumors--possibilities of organ preservation

Whereas 65-70% of ovarian malignancies are of the epithelial type, the occurrence rate of stromal tumors is of approx. 7% and that of germ cell tumors of approx. 15%. Stromal tumors are mostly of the granulosa cell type, whereas germ cell tumors occur mainly as dysgerminoma (occurrence 0.9-2%), endodermal sinus tumors, or teratoma. Organ preservation is discussed in relation to the characteristics of these special tumor types. Granulosa cell tumors, representing 70% of the tumors of the gonadal stroma, occur unilaterally in approx. 97% of cases. 10-year-survival in stage I is over 90%. In stages II and III a complete remission after chemotherapy (acc. to the PVB, VAC, or BEP protocol) may be achieved in approx. 60% of cases. Due to these characteristics organ preservation seems feasible. Since dysgerminoma represent the most common malignant germ cell tumor in children, adolescents and pregnant women (up to 17% of all dysgerminoma are diagnosed during pregnancy), the wish for organ preservation is the more understandable. However, bilaterality, occurring in 20% of cases, has to be considered. Especially in large tumors lymphatic metastases also have to be taken into account. In cases of endodermal sinus tumors and teratoma, overall survival, mainly in patients with advanced disease, depends on the response to an aggressive chemotherapy. Preconditions for organ preservation are the patients' urgent childbearing desire, their information concerning the 5-7% risk of recurrence, an adequate oncologic postoperative care and optimally, after delivery, removal of the contralateral ovary and re-staging. The operative procedure requires removal of the corresponding adnexa, wedge dissection of the contralateral ovary, omentectomy, and depending on the histological tumor type a pelvic, possibly paraaortal lymph node dissection. No generally accepted standards are available for organ preserving surgery of stromal tumors, especially of the granulosa cell type. Prognosis is essentially influenced by a possible rupture being present, tumor size, cellular atypia, and the mitotic index. If one takes into consideration the possibility of lymph node metastases, at least a pelvic lymph node dissection should be recommended. In cases of metastases additionally a chemotherapy (VAC protocol) is indicated. Among germ cell tumors, dysgerminoma and non-dysgerminoma are treated differently. Non-dysgerminoma are endodermal sinus tumors, teratoma, embryonal carcinoma and mixed forms. For both groups operative management may aim at tumor reduction and in principle organ preservation. Whereas for dysgerminoma an adjuvant radiation therapy is feasible, in cases of non-dysgerminoma the response to a chemotherapy is the only factor influencing prognosis. Chemotherapy as adjuvant treatment is not indicated for pure dysgerminoma stage Ia, and pure solid teratoma stage Ia Gl. For all other dysgerminoma adjuvant chemotherapy, VAC protocol, and chemotherapy according the the BEP protocol for non-dysgerminoma is recommended. In cases of metastatic spread, in both groups an aggressive chemotherapy (BEP protocol) is most commonly performed.     

Expression of proliferating cell nuclear antigen in corneas kept in long term culture

PURPOSE: To investigate the proliferative activity of the donor corneal cells and to examine how this property changed during long term culture. METHOD: Fourteen human corneas from donors (ages from 50-91) were cultured in the medium (MEM+8% FBS with or without dextran). The proliferating status of corneal cells was evaluated by immunohistochemical staining of proliferating cell nuclear antigen (PCNA) in the cells. Three corneas at each time point were fixed in paraformalin at day 0, day 3 and after 3 weeks cultured in medium as well as 3 weeks plus 2 or 5 days in fresh medium with 8% dextran. Paraffin-embedded corneas were sectioned to 4 microm and stained with antibody PC 10 against PCNA. The number of PCNA positive cells was identified under light microscope. RESULT: Prior to organ culture only basal limbal epithelial cells stained positive for PCNA. After 3 days in culture 50 percent of the epithelial cells were positive as were several keratocytes and some endothelial cells in the peripheral corneas. After 21 days no cells showed proliferative activity. After 21 days in culture and 5 days in fresh deswelling medium the essentially monolayered epithelium stained positively in the limbal area. The proliferative activity of the keratocytes in the anterior stroma was extensive. Endothelial cells stained positive in the peripheral cornea. CONCLUSION: Limbal epithelial cells appear to survive in the organ culture. The corneas may be worth evaluating as sources of stem cells for grafting. Likewise, the keratocytes survive organ culture and can be induced to proliferate after a change to fresh medium. The endothelium is stimulated to proliferate in organ culture and in fresh medium after long term storage.     

Are minichromosomes valid model systems for DNA replication control? Lessons learned from Escherichia coli

Conventional chemotherapy produces varying degrees of response in patients with many advanced cancers and has significant side effects. Receptors for luteinizing hormone-releasing hormone (LH-RH) are present in a high percentage of human ovarian, prostatic, breast and endometrial tumors and targeted chemotherapy based on cytotoxic analogs of LH-RH might yield better results. The present study was undertaken to determine whether human cancer cell lines express mRNA for LH-RH receptors and epidermal growth factor (EGF) receptors. Using radioligand binding studies, we showed the presence of high-affinity binding sites for LH-RH and EGF in the membranes of human ovarian, prostatic, breast and endometrial cancer cell lines as well as in the JAR choriocarcinoma cell line. The expression of the mRNA for LH-RH receptors and EGF receptors in these cell lines was demonstrated by RT-PCR using specific primers and by subsequent Southern blot analysis. The PCR products obtained were of the expected size, 319 bp for LH-RH receptors and 400 bp for EGF receptors. These findings support the view that cytotoxic analogs of LH-RH could be used for targeted chemotherapy of these cancers. Moreover, the results suggest that these human cancer cell lines might have local regulatory systems for their proliferation based on LH-RH and EGF. Further investigations are required to elucidate the signal transduction pathways involved in the effects of cytotoxic LH-RH analogs on human tumors.     

Laparoscopic surgery combined with preservation of the spleen for distal pancreatic tumors

BACKGROUND: Hair follicle preservation for the purpose of delayed application would help us to transplant hair follicles more efficiently. METHODS: Isolated single hair follicles were preserved at 4 degrees C in four different solutions. Viability of preserved follicles was judged by organ culture and cell culture. In addition, a small number of hair follicles were transplanted into athymic mice. RESULTS. By cell culture, both dermal papilla and outer root sheath cells could be cultivated after 7 days of preservation. Hair follicles preserved for 48 hours showed a significant increase of hair shafts in organ culture. Those preserved for 7 days regrew well when transplanted into athymic mice. CONCLUSION: Preservation of hair follicles at 4 degrees C could be one option to prepare many follicular units at one time for transplantation.     

Modification of an in vitro technique in order to grow adult rat anterior pituitary in organ culture

The study of adult rat anterior pituitary maintained in vitro was made possible by a modification of the suspension system used in the watch-glass method of organ culture. The integrity and health of the tissue was observed with the electron microscope. Somatotrophs and gonadotrophs were seen routinely. A cell with large (400-750 nm) granules and thought to be a luteotroph (mammotroph) was also seen. These results support the use of this method for the growth of adult rat anterior pituitary, or other large explants, for short periods of time in organ culture.     

Establishment of new epithelial carcinoma cell lines by blocking monolayer formation

Human endometrial carcinoma cell lines were established by using a new cell culture technique. The malignant endometrial tumors were grossly disaggregated by mechanical means and cultivated in suspension culture. Adhesion to the bottom of the culture flasks was prevented by first coating the flasks with a thin agarose layer. Four cell lines were derived from 17 samples by this new technique. The cell lines obtained in this way were fully characterized, including karyotyping, intermediate filament staining and transplantation to nude mice. This new technique of initial suspension culture may also be applicable to other human tumors that are equally difficult to cultivate in vitro.     

Enhanced neointimal growth in cultured rabbit aorta following in vivo balloon angioplasty

We have used in vivo balloon catheterization in combination with in vitro organ culture to develop a model system for vascular neointima formation. A Fogarty balloon catheter was used to deendothelialize and rupture the internal elastic lamina of aortae in adult rabbits. After three d of recovery, aortae were harvested, divided into segments, and placed into organ culture. We obtained a daily index of cell proliferation in cultured vessels using [3H]thymidine incorporation into DNA. Also, segments were collected and processed for routine histology or immunohistochemistry. Aortic segments that had undergone ballooning 3 d before harvest and then cultured exhibited diffuse neointimal growth after several d in vitro, whereas those from sham-operated (nonballooned) rabbits showed generally only a single endothelial cell layer that is characteristic of normal intima. Aortae that were harvested, balloon-damaged in vitro, and then cultured exhibited no neointimal growth. The neointima that developed in cultured segments from in vivo ballooned rabbits was primarily of smooth muscle cell origin as determined by positive immunostaining for alpha-smooth muscle actin. The intima:media thickness ratios were significantly higher in aortic segments from ballooned rabbits at harvest and after 4 or 7 d in culture compared with those from nonballooned rabbits. Also, the [3H]thymidine index was higher in the in vivo ballooned aorta compared to non-ballooned or in vitro ballooned vessel. We conclude that ballooning in vivo followed by exposure to blood-borne elements produces an enhanced proliferative response in cultured vessels that is distinct from other in vitro models of neointimal growth.     

Renal cell carcinoma--a current review

Renal Cell Carcinoma is the third most common malignoma in urology. Only little is known about the etiology and risk factors; the age peak lies at 60 and twice as many men than women are affected. The clinical picture presents with a wide spectrum. Over one third of all tumours are detected accidentally by ultrasound or computed tomography in asymptomatic patients. Most common symptoms are hematuria and flank pain, the classical trials including in addition a palpable mass is rare and by mo means an early symptom. Paraneoplastic syndromes include unspecific (increased blood sedimentation rate, weight loss, fever) and endocrine symptoms (hypertension, polyglobulia, hypercalcemia). Diagnosis is based on imaging procedures. By means of sonography renal cysts may be separated from solid, space-occupying tumors. For the latter CT plays a decisive role for staging, therapeutic planning and prognosis. Further radiologic investigations (angiography, MRI) are indicated only in special situations. Rarely a biopsy is necessary for the distinction between renal cell carcinoma and metastases of other primary tumors. The only curative treatment of localized carcinoma is radical nephrectomy. Partial resection is indicated in cases of a single kidney, bilateral tumors and possibly also for tumors smaller than 4 cm in diameter. Radiotherapy is only initiated for palliation of painful skeletal metastases. In case of distant metastases--mainly pulmonary--nephrectomy should only be performed if systemic treatment is planned or if local complaints (pain, hematuria leading to anemia) exist. Chemotherapeutic drugs have no influence on survival. The effect of gestagens on life quality is questionable. Adoptive immunotherapy with cytokines (Interferon-alpha, interleukin-2) appears most promising. These substances, however, not yet been introduced into routine therapy should only be used in prospective studies. Furthermore, renal cell carcinoma is a potential candidate for gene therapy. After tumor nephrectomy follow-up investigations should be performed twice a year, because of the possibility of curative surgical treatment of late solid metastases. Prognosis of tumors restricted to the organ is good. Five year survival after operation is about 90%. However, is distant metastases exist already at the time of diagnosis 5 year survival drops to less than 10%.