AKR mouse leukemia cells in tissue culture. I. Establishment of leukemic cell line AKR 87 and its morphologic and biologic characteristics.

A line of AKR leukemic mouse cells cultured in vitro, designated AKR 87, was established and characterized. Two types of cells were distinguished in this line fibroblasts and lymphoblasts. The lymphoblast-like cells resembled the original tumor cells spontaneous leukemia of AKR mice. In the XC test, cells of this line reacted specifically with XC cells, forming syncytia characteristic of cells infected with mouse leukemia viruses. Ultrathin sections of cells of this line examined on the electron microscope showed presence of type C viral particles.     

Bafilomycin A1 induces apoptosis in the human pancreatic cancer cell line Capan-1

Bafilomycin A₁, a specific inhibitor of vacuolar type H⁺-ATPase, can inhibit the growth of a variety of cultured cells in a dose-dependent manner, but its mechanism is unclear. The aim of this study was to examine whether bafilomycin A₁ inhibits the growth of Capan-1 human pancreatic cancer cells through apoptosis. The effect of bafilomycin A₁ on tumour growth in vitroand in vivowas examined using an MTT assay and an in vivotumour model. The presence or absence of apoptosis was determined by morphology and DNA analysis of tumour cells. The concentration of bafilomycin A₁ for 50 per cent inhibition of cell viability during 72 h by the MTT assay was 5 nm. In DNA analysis, a ladder of fragmented DNA was detected in Capan-1 cells treated with bafilomycin A₁ at concentrations greater than 10 nm for 24 h. Nude mice bearing a xenografted Capan-1 cell line tumour received 4 weeks of bafilomycin A₁ (1·0 mg/kg per day). This treatment significantly inhibited tumour growth compared with controls after 21 days (P<0·05). Histopathological examination of tumour cells in the treated group demonstrated signs of apoptosis with chromatin condensation and cell shrinkage. These observations suggest that bafilomycin A₁ inhibits the growth of Capan-1 human pancreatic cancer cells through apoptosis. © 1998 John Wiley & Sons, Ltd.     

Cardiac myxoma: morphologic, histochemical, and tissue culture studies

Twenty-one cases of cardiac myxoma exhibiting a variety of histologic findings were investigated by light and electron microscopy, tissue culture, and immunohistochemical studies for factor VIII-related antigen (FVIII-RA) and Ulex europaeus 1 (UEA-1) lectin. The cardiac myxoma cells revealed variable cellular arrangements, and some tumor cells revealed vascular-like channels. Immunohistochemically, FVIII-RA was found only in the endothelial-like cells covering the vascular-like channels or slits, whereas UEA-1 lectin reacted not only with myxoma cells having luminal structures or network-like arrangements but also with single cells. On electron microscopy, some myxoma cells revealed differentiation into cells forming vascular structures. In tissue culture, the tumor cells were polygonal and proliferated with extensions of the cytoplasmic processes. Arrangements suggesting vascular channels or slits were not observed. In a coculture of tumor cells and blood clot, the tumor cells covered the surface of the clot. However, angiogenesis was not observed in the tissue culture study. The results of our studies were inconclusive regarding the histogenesis of cardiac myxomas, but it was considered that cardiac myxoma is a neoplasm arising from mesenchymal cells with vasoformative characteristics.     

Anion channels in a human pancreatic cancer cell line (Capan-1) of ductal origin

Transepithelial solute transport and bicarbonate secretion are major functions of pancreatic duct cells, and both functions are thought to involve the presence of chloride channels in the apical membrane of the cell. After being isolated from a human pancreatic adenocarcinoma, the Capan-1 cell line conserves most of the properties of ductal cells and thus constitutes a useful system for investigating the role of chloride channels. Using patch-clamp techniques, we identified three different chloride-selective channels in the apical membrane of confluent Capan-1 cells. Two were non-rectifying chloride channels with low (50 pS) and high (350 pS) unitary conductances. Both channels were active in cell-attached recordings, and they were consistently located together in the same patch. Maxi Cl^– channels displayed multiple subconductance states, and were reversibly inactivated by either positive or negative voltage changes, which indicates that they were optimally opened at the cell resting potential. The third was an outwardly rectifying chloride channel with a unitary conductance of 38 pS and 70 pS at negative and positive potentials respectively. Rectifying Cl^– channels were clustered in discrete loci. They were silent in situ, but became active after patch excision. In inside-out excised patches, the three channels displayed a high selectivity for Cl^– over monovalent cations (Na⁺ and K⁺) and gluconate. They were blocked by 20–200 M 4,4-diisothiocyanatostilbene-2,2-disulfonic acid (DIDS) and were insensitive to changes in the Ca²⁺ concentration. Our results show that the apical membrane of Capan-1 cells contains a high density of chloride channels; these channels may provide pathways for transepithelial solute transport as well as for bicarbonate secretion.     

Involvement of the mitochondrial pathway in bruceine D-induced apoptosis in Capan-2 human pancreatic adenocarcinoma cells

The fruit of Brucea javanica L. is a common herb used in Chinese medicine for the treatment of a variety of cancers. Our research group has previously identified bruceine D (BD), a quassinoid found abundantly in B. javanica, to have potent cytotoxic effect on a number of pancreatic cancer cell lines, including Panc-1, SW1990 and Capan-1 cells. In the present study, we showed that BD was also able to inhibit the growth of the Capan-2 human pancreatic adenocarcinoma cell line, but it exerted only modest cytotoxicity on the WRL68 human hepatocyte cell line and a human pancreatic progenitor cell line. The antiproliferative effects of BD were comparable to those exhibited by camptothecin and gemcitabine in our culture system. We found a dose-dependent decrease of the mitochondrial membrane potential in BD-treated Capan-2 cells as measured by the JC-1 assay. BD exposure was able to attenuate the expression of Bcl-2 protein in Capan-2 cells as detected by western blot analysis. In addition, the expression of both caspase 9 and caspase 3 in BD-treated Capan-2 cells was significantly accentuated. Moreover, BD was capable of inducing the fragmentation of genomic DNA in Capan-2 cells as evidenced by Hoechst staining. Cell cycle analysis demonstrated that BD could increase the percentage of Capan-2 cells in the subG1 phase in a dose-related manner. An increase in the apoptosis of Capan-2 cells was also observed by Annexin V and PI staining. These results unequivocally indicate that BD induces cytotoxicity in Capan-2 cells via the induction of cellular apoptosis involving the mitochondrial pathway.     

Expression of GLUT1 in primary renal tumors: morphologic and biologic implications

This study aimed to assess whether glucose transporter 1 (GLUT1) is useful in prognostication or differential diagnosis of renal tumors. GLUT1 immunostain for 228 renal tumors showed a membranous or cytoplasmic pattern. The membranous pattern was seen in 86.2% of 145 clear cell renal cell carcinomas (RCCs) and 100% of 11 transitional cell carcinomas (TCCs) but in no oncocytomas, other subtypes of RCC, or sarcomatoid areas of RCCs. The cytoplasmic pattern was seen in 55.2% of 145 clear cell RCCs, 38% of papillary RCCs (11/29), 13% of chromophobe RCCs (2/16), 22% of oncocytomas (5/23), and 82% of TCCs (9/11). Western blot showed a markedly increased GLUT1 protein content in clear cell RCCs compared with a low level in papillary RCCs and normal kidney specimens. GLUT1 expression in clear cell RCC was not significantly correlated with patient survival, tumor grade, or tumor stage. GLUT1 may be a novel target for immunotherapy and a useful marker in the differential diagnosis and classification of renal tumors.     

KISS1 over-expression suppresses metastasis of pancreatic adenocarcinoma in a xenograft mouse model

Identifying molecular targets for treatment of pancreatic cancer metastasis is critical due to the high frequency of dissemination prior to diagnosis of this lethal disease. Because the KISS1 metastasis suppressor is expressed at reduced levels in advanced pancreatic cancer, we hypothesized that re-expression of KISS1 would reduce metastases. Highly metastatic S2VP10 cells expressing luciferase (S2VP10L) were transfected with a FLAG-tagged version of KISS1 (KFM), KFMΔSS (with deleted secretion signal sequence), or pcDNA3 control plasmid (CP) and expression was confirmed by RTQ-PCR. SCID mice were implanted orthotopically with S2VP10L cells or transfectants and tumor growth and metastases were monitored using bioluminescence imaging. Mice with S2VP10L-KISS1 tumors developed fewer liver (98%) and lung (99%) metastases than S2VP10L. Unexpectedly, mice with S2VP10L-KFMΔSS tumors also had reduced liver and lung metastases, but had more metastases than mice with S2VP10L-KISS. KISS1 protein was found in the cytoplasm of both KFMΔSS and KISS1-expressing orthotopic tumors by immunohistochemistry. Metastases were not found in lungs of mice with S2VP10L-KISS1 tumors; whereas, KFMΔSS lung sections had regions of concentrated KISS1 staining, suggesting that secretion of KISS1 is needed to reduce metastasis significantly. These data suggest induction of KISS1 expression has potential as an adjuvant treatment for pancreatic cancer.     

Inhibition of SRC expression and activity inhibits tumor progression and metastasis of human pancreatic adenocarcinoma cells in an orthotopic nude mouse model

The nonreceptor protein tyrosine kinase Src is overexpressed in 70% of pancreatic adenocarcinomas. Here, we describe the effect of molecular and pharmacological down-regulation of Src on incidence, growth, and metastasis of pancreatic tumor cells in an orthotopic model. Src expression in L3.6pl human pancreatic tumor cells was reduced by stable expression of a plasmid encoding small interfering RNA (siRNA) to c-src. In stable siRNA clones, Src expression was reduced >80%, with no change in expression of the related kinases c-Yes and c-Lyn, and proliferation rates were similar in all clones. Phosphorylation of Akt and p44/42 Erk mitogen-activated protein kinase and production of VEGF and IL-8 in culture supernatants were also reduced (P < 0.005). On orthotopic implantation of varying cell numbers into nude mice, tumor incidence was unchanged; however, in the siRNA clones, large tumors failed to develop, and incidence of metastasis was significantly reduced, suggesting that c-Src activity is critical to tumor progression. To examine this possibility further, animals bearing established wild-type tumors were treated with the Src/Abl-selective inhibitor BMS-354825 (dasatinib). Tumor size was decreased, and incidence of metastases was significantly reduced in treated mice compared with controls. These results demonstrate that Src activation contributes to pancreatic tumor progression in this model, offering Src as a candidate for targeted therapy.     

Comparison of biochemical, morphologic, and chemical characteristics of Centers for Disease Control fermentative coryneform groups 1, 2, and A-4.

A total of 24 strains of fermentative coryneform like bacteria isolated from clinical specimens form two distinct groups which have been designated Centers for Disease Control (CDC) fermentative coryneform groups 1 (13 strains) and 2 (11 strains). The phenotypic characteristics of group 1 were similar to those of a previously described CDC group designated A-4, with the major differentiating characteristic being the inability to hydrolyze esculin. Major differences in cellular fatty acid composition between CDC groups 1 and A-4 were also observed. The branched-chain fatty acids 14-methylhexadecanoate and 12-methyltetradecanoate, which account for more than 80% of the total acids of group A-4, were not detected in cells of group 1 strains. Groups 1 and 2, which have similar cellular fatty acid compositions, can be differentiated on the basis of fermentation of xylose, mannitol, lactose, sucrose, and melibiose by group 1 but not by group 2. The sources of isolation of the strains of both groups varied. Only group 1 strains were associated with eye infections.     

Progressive pulmonary fibrosis in rats: a biochemical, cell kinetic, and morphologic analysis

The concomitant treatment of rats with bleomycin and hyperoxia results in synergistic development of pulmonary injury. We exposed rats to 70% oxygen for 72 hr following an intratracheal instillation of bleomycin (0.2 U/kg body wt). Animals were killed 15, 30, 60 and 90 days after treatment for hydroxyproline, cell kinetics, and histopathologic analysis. A 16% increase in hydroxyproline over controls was seen 15 days after treatment which was manifested by the proliferation phase of diffuse alveolar damage and an increase in cell labeling by tritiated thymidine. Thirty days after treatment the hydroxyproline remained elevated while lung injury appeared to be healing with a residual focal interstitial pneumonitis and a drop in cell labeling. Between 60 and 90 days, there was an additional significant increase in hydroxyproline to 44% over controls. Diffuse interstitial pneumonitis with fibrosis was observed. Cell labeling remained constant between 60 and 90 days. We conclude that the treatment of rats with bleomycin and hyperoxia results in slowly progressive pulmonary fibrosis. The increase in hydroxyproline in the chronic phase was not accompanied by an increase in cell proliferation, and therefore may have resulted from an increase in cellular production of hydroxyproline rather than increased number of cells producing collagen.     

Inherited infantile dilated cardiomyopathy in dogs: genetic, clinical, biochemical, and morphologic findings

Dilated cardiomyopathy, a lethal disease characterized by left ventricular dilation and systolic dysfunction, is relatively common in humans and other mammals. Idiopathic dilated cardiomyopathy (IDCM) is a primary myocardial disease of unknown cause and can be a familial disorder. This report describes autosomal recessive IDCM in dogs. It occurs in Portuguese Water Dog (PWD) pups and is manifested by acute, vague clinical signs and sudden death. Affected pups have progressive reduction of fractional shortening that can be demonstrated by echocardiography prior to the development of clinical signs. Furthermore, these pups have low plasma taurine levels when consuming certain diets. Affected pups had dilation of the left ventricle and alterations in the sarcomere appearance, while immunohistochemical and biochemical studies demonstrate an increase in desmin, a cytoskeleton protein. The clinical and morphologic findings of IDCM in PWDs are distinct from those reported in adult IDCM. Finally, the clinical and echocardiographic manifestations were reversible in some pups following oral taurine supplementation for 2 months. These results suggest that IDCM in PWDs is correlated with low plasma taurine levels.     

Cerebral glycogenosis, alpha particle type: morphologic and biochemical observations in an infant

A 3-month-old infant with congenital hypotonia suffering from an unusual form of glycogenosis is reported. The most striking neuropathologic findings were vacuolation of neuropile and glycogen accumulation, especially in the cerebral cortex and cerebellar molecular layer. Ultrastructurally, glycogen accumulation was present mainly in neurites and astrocytic processes, and mostly appeared as rosettes (alpha glycogen particles). Biochemical analysis of glycogen in various regions of the central nervous system showed an increase of up to 100-fold. The cerebral cortex, deep nuclei, and cerebellar cortex had the highest glycogen elevations, while the cerebral white matter glycogen level was normal. Among other tissues, the heart showed a several-fold increase in glycogen content. Muscle, liver, and kidney glycogen levels were not elevated. Findings in this case and in three other reported patients with cerebral glycogenosis of alpha particle type are discussed.     

小鼠胸腺基质细胞系(MTEC1)在裸鼠体内生物学特性研究

通过流式细胞仪（ＦＡＣＳ）、组织学染色和免疫组化的方法研究了脾内注射的小鼠胸腺上皮细胞系ＭＴＥＣ１和初代培养的小鼠胸腺基质细胞在裸鼠脾脏内存活状态及功能特性。结果发现ＭＴＥＣ１细胞不仅能够在脾脏内存活，而且在ＭＴＥＣ１细胞周围有大量不成熟的淋巴细胞。初代培养的小鼠胸腺基质细胞则不能在脾脏内存活。     

AKR mouse leukemic cells in tissue culture. II. Immunologic studies on the AKR 87 cell line.

The continuous AKR 87 cell line was derived from the thymus and spleen of AKR mice with spontaneous leukemia. Previous studies showed that the line has retained the original morphologic features of leukemic cells, reacts positively in the XC test, and produces virus particles of type C morphology. The present paper presents an immunologic characterization of cells of the AKR 87 line and of the virus produced by them, in comparison with the cells of spontaneous leukemia of AKR mice, TGV line productively infected with Gross virus, and normal mouse tissues. Results of the hemagglutination test, immunoprecipitation in agar gel, cytotoxic test and immunofluorescence indicate that the AKR 87 line produces virus antigen of the Gross type.