Interleukin-1 regulates interleukin-6 secretion in human oral squamous cell carcinoma in vitro: possible influence of p53 but not human papillomavirus E6/E7.

We have previously shown that interleukin-1 (IL-1) and IL-6 are constitutively produced by human oral squamous cell carcinoma (SCC) and some derived cell lines but not by cultured normal oral keratinocytes. To elucidate possible cytokine regulatory pathways that may contribute to oral SCC growth and/or progression, we tested the hypotheses that exogenous and/or endogenous IL-1 regulates IL-6 production in vitro. We investigated the effects of exogenous IL-1 and IL-6 on secondary cytokine secretion. Our studies revealed that IL-1 strongly up-regulated IL-6 protein secretion in all three cell lines tested. This effect was completely abrogated by IL-1 receptor antagonist. IL-1 receptor antagonist also inhibited the secretion of IL-1alpha and IL-1beta in two of three cell lines. These data show for the first time that IL-1 strongly up-regulates IL-6 and support the notion of autocrine regulation of IL-1 in certain oral SCC cell lines. Additionally, because human papillomavirus (HPV) infection and p53 mutation have been implicated in the malignant transformation of SCC, we explored a second hypothesis, that HPV and/or p53 mutation contribute to cytokine dis-regulation. We investigated HPV DNA presence, transcriptional activation of HPV E6/E7 (in HPV DNA-positive cell lines), and p53 gene status in our cell lines. No association between HPV DNA and cytokine expression was found. However, the oral SCC cell lines secreting the most IL-6 had mutant rather than wild-type p53.

Interleukin-6 production and secretion in human melanoma cell lines: regulation by interleukin-1.

These investigations were designed to test the hypothesis that exogenous and/or endogenous interleukin-1 (IL-1) regulates interleukin-6 (IL-6) production in human melanoma cell lines. Ten cell lines were examined for IL-1 and IL-6 expression. Six of these 10 lines constitutively expressed detectable IL-6 mRNA by RT-PCR; three of these six cell lines also produced intracellular and secreted IL-6 as evidenced by positive reaction for IL-6 using immunohistochemistry staining and ELISA methods; three others produced only intracellular IL-6. Addition of exogenous IL-1 alpha was shown to have the following effects on IL-6 production: first, de novo induction of detectable IL-6 intracellular protein and secreted IL-6 in a cell line void of either; second, stimulation of IL-6 secretion in all three cell lines producing only intracellular IL-6 protein; and third, quantitative enhancement of IL-6 secretion in cell lines that constitutively secreted IL-6. Three of the 10 lines which secreted IL-6 also constitutively secreted IL-1 alpha. Experiments employing the IL-1 receptor antagonist confirmed an extracellular receptor-mediated role of IL-1 in regulation of IL-6 production in such cells. These results indicate that IL-1 can regulate IL-6 in human melanoma cells; however, heterogeneity in the constitutive expression as well as variability in response exists with respect to these two cytokines.

Interleukin-1 production in tumor cells of human melanoma surgical specimens.

To determine whether IL-1 alpha and/or IL-1 beta protein is expressed by human melanoma tumor in vivo, we first analyzed nine human melanoma cell lines and optimized the in situ detection of these proteins. Three of the melanoma cell lines stained positively for both IL-1 alpha and IL-1 beta using immunohistochemistry (IHC). THe specificity of IHC was confirmed by the ability of purified recombinant IL-1 alpha and IL-1 beta protein to abolish the staining after being adsorbed by their respective antibodies before use in IHC. The three positively staining cell lines were also the only lines to demonstrate IL-1 production by western blot analysis as well as IL-1 secretion by ELISA. Next we examined 29 surgically obtained melanoma tumor specimens (6 primary and 23 metastases) that had been formalin fixed and paraffin embedded. Using the same anti-IL-1 antibodies, 5 of 23 metastatic tumors stained positively. None of the 6 primary lesions stained for either IL-1 alpha or IL-1 beta. Comparison of staining pattern performed on serially sectioned tissue using preimmune serum and antibodies against S-100 protein, melanoma-associated antigen (HMB-45), and CD68 (kappa P1), which recognizes monocyte-macrophage cell lineage, demonstrates for the first time that IL-1 protein is produced by human melanoma tumor cells in vivo. These findings provide the basis for examination of what may be a previously unrecognized biologically distinct subset of patients.

Disruptive, institutionalized elderly: a cost-effective intervention.

1. Psychomotor agitation can be decreased without the use of physical or chemical restraints. 2. A structured activity program can be integrated into the treatment plan of disruptive patients. 3. Nurses working in long-term care settings are in positions to be advocates for change.

Management of severe intra-abdominal sepsis: single agent antibiotic therapy with cefotetan versus combination therapy with ampicillin, gentamicin and metronidazole.

In a prospective, randomized trial involving 100 patients with severe intra-abdominal sepsis, the value of single agent antibiotic therapy with cefotetan was compared with that of combination therapy of ampicillin, gentamicin and metronidazole (AGM). All patients underwent exploratory laparotomy. The mortality rate was 3 per cent, all deaths occurring within 48 h of operation. Two-thirds of patients were considered severely ill on admission, and one-third were moderately ill. Six patients had positive blood cultures on entry into the study. The mean age was 31 years and concurrent disease was present in 14 per cent of the patients. A satisfactory response was achieved in 82 per cent of patients receiving cefotetan and in 65 per cent of those receiving AGM, whereas the response was unsatisfactory in 18 per cent of cefotetan patients and 35 per cent of those receiving AGM (P = 0.075 n.s.). Significant changes in laboratory values during the study occurred in 51 per cent of patients, and 7 per cent required vitamin K administration for hypoprothrombinaemia. The results of this study suggest that antibiotic therapy with single agent cefotetan is as safe and effective as a combination of ampicillin, gentamicin and metronidazole in patients with severe intra-abdominal sepsis requiring operative management.

Evidence that pancreatic proteases enhance vitamin B12 absorption by acting on curde preparations of hog gastric intrinsic factor and human gastric juice.

Crude preparations of hog gastric intrinsic factor or their own previously collected gastric juices administered with labeled vitamin B12 did not enhance vitamin B12 absorption in patients with vitamin B12 malabsorption secondary to pancreatic insufficiency. However, when these sources of gastric intrinsic factor were incubated with three times crystallized preparations of insolubilized bovine trypsin or chymotrypsin, the proteolytic enzymes were removed by centrifugation, and the preparations of gastric intrinsic factor were readministered to these patients, the absorption of vitamin B12 was markedly enhanced. Studies of hog gastric intrinsic factor before and after exposure to proteolytic enzymes failed to show any difference on Sephadex chromatography or polyacrylamide gel electrophoresis or on its affinity for vitamin B12 or the ileal receptor in guinea pigs. These investigations demonstrate that: (1) gastric intrinsic factor as secreted by subjects with pancreatic insufficiency or obtained from hog pyloric mucosal extracts is ineffective in promoting vitamin B12 absorption in patients with pancreatic insufficiency, (2) incubation of crude preparations of gastric intrinsic factor with insolubilized pancreatic proteases modified these preparations of gastric intrinsic factor in an as yet undefined manner, allowing them to enhance vitamin B12 absorption, and (3) in vitro studies using gut sacs or brush border preparations do not reflect the abnormality in vitamin B12 absorption associated with pancreatic dysfunction.