Influence of gangliosides on primary and metastatic neoplastic growth in human and murine cells.

The influence of gangliosides on tumor growth and frequency of metastasis in vivo as well as on growth and motility of neoplastic cells in vitro was tested utilizing human and rodent cell populations. In mice receiving injections of a ganglioside mixture twice daily the tumor volume, the number of spontaneous metastases per animal, and the number of mice with metastasis was approximately double that of controls. Preincubation of neoplastic cells with the ganglioside mixture doubled the number of metastatic foci in the lungs of mice receiving the cells by i.v. injection. Addition of a ganglioside mixture to the culture medium enhanced motility of neoplastic cells about 3-fold. This finding was similar to that observed for capillary endothelium. The presence of gangliosides in the culture media for a 48-h incubation period about doubled the number of neoplastic cells as compared to controls; the same was observed for capillary endothelium. The data are interpreted to indicate that gangliosides improve growth and mobilization of capillary endothelium and neoplastic cells. Both events may concur in enhancing tumor growth in vivo, the first by improving angiogenesis, the second by direct action on the neoplastic cell population.

A new tumour associated antigen of non-small cell lung cancer: tumour liberated proteins (TLP)--a possible new tumor marker.

TLP (Tumour Liberated Proteins) is a 214 kDa protein, isolated from lung cancer tissue and synthetic nonapeptide CSH-275 is a major epitope identified on a 100 kDa TLP fragment and used to create antibodies in rabbit (antiserum termed CSH-419). CSH-419 antiserum, labelled or conjugated as necessary, was used to detect TLP on sera from NSCLC patients by a new ELISA test set up as a 1 step sandwich format test. This ELISA was performed on sera from 534 individuals. TLP was detected in 53.1% of NSCLC patients, with a 0% response in patients with cancers other than NSCLC, 7.6% response in unknown blood donors, and 17.4% response in patients with chronic lung diseases correlated with an elevated risk for lung cancer. TLP was particularly present in early stages of disease: 75% in stage I, 56% in stage II and III and 45% in stage IV. The presence of TLP antigen in sera from NSCLC patients indicates that TLP could represent an useful tumour marker.

Involvement of the membrane-bound Na,K ATPase in the evolution of experimental injuries of the spinal cord.

Rat spinal cords have been compressed at the region corresponding to D4-D5 by a 50 mg/cm force. After 5, 30 and 60 min this section has been dissected together with the surrounding cord. The ATPase activity of the homogenates was decreased, suggesting an involvement of this enzyme in the generation of edema.

Ultrastructural and biological observations on neoplastic growth control obtained by contact inhibition.

Friend erythroleukaemia and HeLa cells grown in suspension were artificially kept in close contact by centrifugation in capillary tubes for short periods. This treatment induced evident inhibition of the growth rate in both cell lines and a parallel decrease of labeled nucleotide incorporation. Electron microscopy showed extensive close contact of the plasma membranes in Friend erythroleukaemia cells, and the appearance of junctional complexes between HeLa cells.

Influence of genetic and physiological properties of the host cell on the cytopathic expression of herpes simplex virus.

Two plaque morphology variants, a cell aggregating variant and a syncytial variant, were isolated from MDBK cells infected with the MP mutant of herpes simplex virus, type 1. The variants differed in the polypeptides produced in infected MDBK cells. The properties of the variants were stable on passage in cells and both variants produced only syncytia in KB and Hep-2 cells. The physiological state of MDBK cells influenced the cytopathological expression of the infecting virus, so that, under certain conditions, each variant could shift from one type of plaque morphology to the other. However, attempts to correlate this plaque morphology shift with a difference in the glycopolypeptides synthesized in the infected cells were unsuccessful.

[Substances with antiviral. XVI. Thiosemicarbazones containing benzofuran and 1H-indene moieties]. / Ricerche su sostanze ad attività antivirale. Nota XVI--Tiosemicarbazoni contenenti unità benzofuranica e 1H-indenica.

A few hydrazones with benzofuran and 1H-indene moieties were synthesized and screened in vitro against vaccinia virus strain IHD, parainfluenza type 3 virus strain HA-1/CR-8, and the MP mutant of herpes simplex virus type 1 [HSV-1 (MP)]. Only the thiosemicarbazones were active. The thiosemicarbazone of 3-chloro-2-formyl-1H-indene inhibited vaccinia virus to a greater extent than methisazone, used as reference standard. Furthermore, this compound was active also against parainfluenza and herpes viruses.

[CAMP mediated cell growth regulation. I. Characterization of protein kinases in CHO cells]. / Regolazione della crescita cellulare da parte del cAMP. I. Caratterizzazione della proteinkinasi in cellule CHO.

Protein kinases in wild-type CHO cells have been characterized. Cells cultured on MEM were collected, homogenized and the extract assayed for protein kinase activity. DEAE cellulose chromatography of 30.000xg extract yields 2 peaks of protein kinases activity, PKI and PKII. The two peaks when analyzed for the binding of 8-N3-(32P)cAMP show two subunits RI and RII and a RI not associated with the enzymatic activity, named RF. This characterization allows us to discuss the meaning of protein kinases in the modulation of the growth regulating effects of cAMP.

[cAMP mediated cell growth regulation. II. Characterization of the biochemical change responsible for resistance to cAMP treatment]. / Regolazione della crescita cellulare da parte del cAMP. II. Caratterizzazione delle alterazioni biochimiche responsabili delle resistenze al trattamento col cAMP.

In this paper we characterize the biochemical defect of a mutant (10248) of CHO cells, resistant to the cAMP treatment. Cells cultured on MEM were collected each three days, homogenized and centrifuged. The cell extract was assayed for protein kinases activity and the binding of 8-N3-(32P)cAMP. The same extract was also applied on to a DEAE cellulose column, eluted with a linear gradient and the fractions tested for the phosphotransferase activity and 8-N3-(32P)cAMP binding. Mutant 10248 shows a different profile of protein kinases activity as compared to 10001 control. Protein kinases II is absent whereas a normal RII binding activity is present. RI shows altered affinity for cAMP.

[EGF modulated Na+/K+ ATPase in cultured fibroblasts]. / Modulazione della Na+/K+ ATPasi da parte dell'EGF in coltura di fibroblasti.

The behaviour of Na+/K+ ATPase during cell growth has been studied. Human cultured fibroblasts were used in the presence or absence of EGF. Sample and control cultures were stopped by gathering and washing the cells with tris buffer. Homogenates were tested for Na+/K+ ATPase activity by the method of incubating and for the -SH groups content (Ellman). Na+/K+ ATPase activity that slightly increases in the controls is strongly reduced by the addition of EGF. The behaviour shows evidence for a double mechanism of action: I) involvement of the cAMP system 2) decrease of the -SH group availability.

Pharmacokinetic and therapeutic activity of polyinosinic-polycytidylic acid stabilized with poly-L-lysine in carboxymethylcellulose [poly(I,C)-LC].

Polyinosinic-polycytidylic acid stabilized with poly-L-lysine in carboxymethylcellulose [poly(I,C)-LC] significantly augmented natural killer (NK) cell activity in several tissues. Macrophage (M phi) tumoricidal activity was also markedly increased. Both effector cells were active for 9 days. Poly(I,C)-LC also increased effector cell response in vitro. Injections of poly(I,C)-LC resulted in elevated effector cell responses in four of five routes tested. Treatment with poly(I,C)-LC led to an earlier reconstitution of bone marrow cells, NK cell activity, and M phi effector cell activity in mice pretreated with cyclophosphamide (Cytoxan). Combined treatment of MBL-2 tumor cells with cytoreductive chemotherapy and poly(I,C)-LC resulted in an enhanced therapeutic response.

Isolation of CF cell lines corrected at DeltaF508-CFTR locus by SFHR-mediated targeting.

Cystic fibrosis is the most common inherited disease in the Caucasian population. About 70% of all CF chromosomes carry the DeltaF508 mutation, a 3-bp deletion that results in the loss of a phenylalanine at amino acid 508 in the CF transmembrane conductance regulator (CFTR) protein. Direct modification of the DeltaF508 locus of endogenous CFTR was achieved by small fragment homologous replacement (SFHR). Transformed human airway epithelial cells (CFBE41o(-)), homozygous for DeltaF508 mutation, were transfected with small fragments (491-bp) of wild-type (WT) CFTR DNA comprising exon 10 and the flanking introns. The DNA fragments were in a liposome-DNA complex at a charge ratio of 6:1 (+:-), respectively). The population of transfected cells was subcloned by limiting dilution at approximately 1 cell/well in 96-well plates. Individual colonies were isolated and analyzed. The DNA from several colonies was characterized by radiolabeled, nonallele-specific and radiolabeled, allele-specific PCR amplification, as well as by genomic DNA fingerprinting. The CFTR-WT allele was detected in five of these colonies by allele-specific PCR amplification thus indicating that the cell lines carried both WT and DeltaF alleles. DNA fingerprint analysis confirmed that the colonies were isogenic and derived from the parental CFBE41o(-) cell line. Although, the WT allele was detected by allele-specific PCR, it was not detected initially when the same samples were analyzed by non allele-specific PCR. A sensitivity assay, mixing the genomic DNA of wild-type (16HBE14o(-)) and mutant (CFBE41o(-)) cell lines, indicated that the allele-specific PCR was at least 25-fold more sensitive than non allele-specific PCR. These results suggest that the colony is not yet clonal, but still contains a population of parental, CFBE41o(-) cells that have not been modified. Based on the mixing analysis, the proportion of corrected cells appears to be between 1 and 10% of the total population. Nonallele-specific reverse transcriptase PCR (RT-PCR) analysis of the CFTR mRNA indicated that two of the colonies expressed both WT and DeltaF508 CFTR mRNA, while one colony appeared to express only the WT mRNA. The mRNA results were confirmed by sequence analysis of 3' end primer extension products from the mRNA of CFTR exon 10 showing that the mRNA containing exon 10. Furthermore, a survey of primer extension products indicated no random insertion of the fragment in an expressed gene. This study demonstrates SFHR-mediated modification of the DeltaF508 allele in DeltaF508 homozygote human airway epithelial cells over multiple generations. The resultant cells express WT-CFTR mRNA and can be subcloned further to isolate isogenic clonal populations of cells.

[Substances with antiviral activity. XV. Preparation and antiherpes activity of alkyl- and acylamino-dihalogenated pyrimidines and pyridines]. / Ricerche su sostanze ad attività antivirale. Nota XV - Preparazione e attività antierpetica di alchil- e acilammino- -dialogeno-pirimide e -piridine.

Some dihalo-amino-pyrimidines and -pyridines were alkylated and acylated at the amino group. The resulting twenty-four compounds were then tested for their action on Herpes simplex virus infection in human HEp-2 cell cultures. Five compounds were active and 2-benzamido-3,5-dichloropyridine [(III B); Table I] showed the highest antiviral activity.

Antimitotic and antiviral activities of Kelletinin A in HTLV-1 infected MT2 cells.

Kelletinin A [ribityl-pentakis (p-hydroxybenzoate)] (KA), a natural compound isolated from the marine gastropod Buccinulum corneum, showed antiviral activity on the human T-cell leukemia virus type-1 (HTLV-1) and antimitotic activity on HTLV-1-infected MT2 cells. KA inhibited cellular DNA and RNA synthesis, without influencing protein synthesis, and interfered with viral transcription by reducing the levels of high molecular weight transcripts. Finally, the compound inhibited HTLV-1 reverse transcriptase in vitro.