A novel polymorphism in the promoter of the RAGE gene is associated with non-small cell lung cancer.

The receptor for advanced glycosylation endproducts (RAGE) is abundant at both the transcriptional and translational level in normal lung but is not expressed in non-small cell lung cancer (NSCLC). In order to determine whether sequence variations might be responsible for the inactivation of RAGE in NSCLC, we investigated the RAGE gene in primary NSCLCs and in the corresponding normal tissues of nine patients. Although sequence analysis revealed no somatic, tumor-associated mutations, six novel sequence variants were identified: T-->A in the promoter region 388 bp upstream of the start codon: T-->A in exon 1 (Ala2Ala), C-->G in exon 3 (Val89Val), C-->T in intron 6, G-->C and C-->G in exon 10 (Arg365Ser and Arg369Gly). In addition, we detected a 63 bp deletion in the promoter region (358-421 bp upstream of the start codon) in one NSCLC patient. The T-->A transversion in the promoter region was detected in three of nine patients. Further analysis of this polymorphic locus in 54 NSCLC patients and 59 non-cancer controls revealed a significant difference in the genotype distribution between NSCLC patients and controls. Interestingly, the AA genotype was more common in NSCLC patients (20.8%) than in controls (3.5%). The cumulative occurrence of the AA variant in NSCLC suggests that this genotype is a putative risk factor for NSCLC development.

Genomic organization and chromosomal mapping of SPARC-like 1, a gene down regulated in cancers.

Human SPARC-like 1 (SPARCL1), also known as MAST9 or hevin, is a member of the SPARC protein family. Originally we identified SPARCL1 as one of the genes down regulated in human non-small cell lung cancer (NSCLC). Recent reports indicate that the down regulation of SPARCL1 also occurs in prostate and colon carcinomas, suggesting that SPARCL1 inactivation is a common event not only in NSCLCs but also in other tumors of epithelial origin. In the present work we report the cloning and mapping of the genomic locus of human SPARCL1. Using fluorescence in situ hybridization analysis, SPARCL1 was localized to chromosome 4q22-25, a region often deleted in human cancers. Furthermore, we show that the intron/exon organization of the human SPARCL1 gene is similar to its murine homologue SC1. SPARCL1 contains 11 exons and 10 introns which span approximately 47 kb of the genome. We also sequenced the 5'-flanking region of the human SPARCL1 gene containing 2.4 kb of the putative promoter region. The data presented herein are a prerequisite for deletion/mutation analysis of the SPARCL1 gene in tumors. In addition, knowledge of the SPARCL1 promoter sequence allows to investigate the regulation of SPARCL1 expression on the transcriptional level. Taken together our results will help to clarify the function of SPARCL1 in tumor formation.

Activity of gemcitabine and continuous infusion fluorouracil in advanced pancreatic cancer.

BACKGROUND/OBJECTIVES: Gemcitabine has been shown to improve survival and quality of life parameters compared to fluorouracil alone in advanced pancreatic cancer [J Clin Oncol 1997;15:2403-2413]. However, fluorouracil was given as a weekly bolus in that study and other administration schedules might be more effective. The objective of this trial was to determine the activity and toxicity of gemcitabine in combination with continuous infusion (CI) fluorouracil in advanced pancreatic cancer. PATIENTS AND METHODS: Chemotherapy-naïve patients with measurable advanced adenocarcinoma of the pancreas were treated with gemcitabine 1,000 mg/m(2) intravenously weekly x 3 followed by 1 week of rest every 4 weeks and 200 mg/m(2)/day CI fluorouracil until disease progression or limiting toxicity. RESULTS: Twenty-five patients were evaluable for response and toxicity. Objective partial responses were documented in 5 patients (20%; 95% confidence interval 6.8-40.7%) and disease stabilization or minor responses in 13 patients (52%; 31.3-72.2%). Toxicity was mild with grade 2/3 leucopenia in 26%, stomatitis in 15%, nausea in 6%, diarrhea in 3%, and hand-foot syndrome in 2% of the treatment cycles. In 3 patients a catheter thrombus occurred and in 1 patient the treatment had to be stopped due to asthenia. The performance status improved in 39% of the patients and 65% benefitted in terms of a decrease in pain intensity or consumption of analgesics. CONCLUSION: This phase II trial confirms a significant antitumor activity and a beneficial clinical effect of gemcitabine plus CI fluorouracil in advanced pancreatic cancer. The combination is well tolerated and it will have to be shown whether oral fluoropyrimidines can increase the practicability of this treatment without impairing efficacy.

Simple and fast method to test the receptor for advanced glycosylated endproducts (RAGE) for its tumor suppressive potential using the Tet-On system.

The Tet gene expression system, that allows tightly controlled gene expression in response to doxycycline, was applied to analyze the influence of the receptor for advanced glycosylation endproducts (RAGE) on the growth of 293 cells in semi-solid medium. Establishing a Tet-On gene expression system involves two consecutive stable transfections. Here, we describe an alternative procedure to obtain a Tet-On gene expression system in a single transfection step for the use in tumor biology. The plasmids necessary for the regulated expression of RAGE together with the selectable marker plasmid were cotransfected in a molar ratio of 6:1. After aminoglycoside selection, 29 clones were analyzed using PCR revealing 8 colonies to be double stably transformed. Subsequent Western blot analysis showed inducible expression in 7 cell lines. Applying the one step protocol, the entire Tet-On expression system could be completed in half of the time required for the original two step method. The generated 293 double stable cells were used in the clonogenic assay for the testing of the tumor suppressive potential of RAGE.

Fibroblasts stimulate acinar cell proliferation through IGF-I during regeneration from acute pancreatitis.

Pancreatic regeneration after caerulein-induced pancreatitis is characterized by transient fibroblast proliferation followed by replication of acinar cells. The mechanisms that coordinate regeneration are incompletely understood. In this study, we examine the role of insulin-like growth factor I (IGF-I). Acute edematous pancreatitis was induced in rats by 12 h caerulein infusion. Pancreatic IGF-I mRNA levels increased over 50-fold during regeneration, reaching a maximum at day 2. Immunohistochemically, IGF-I was localized to fibroblasts within the areas of interstitial tissue. IGF-I mRNA was demonstrated in primary cultures of pancreatic fibroblasts but not in cultured pancreatic acinar cells. However, with the use of Western blotting acinar cells did express IGF-I receptors. IGF-I stimulated 5-bromo-2'-deoxyuridine uptake and increased numbers of acinar cells in a dose-dependent manner. Stimulation was half maximal at 1.1 nM and completely inhibited by an IGF-I antagonist and by IGF binding protein-3 (IGFBP-3). Possible paracrine regulation was confirmed by stimulation of acinar cell proliferation with fibroblast-conditioned medium, which was partially inhibited by IGF-I antagonist or by IGFBP-3. We conclude that acinar cell proliferation during late regeneration from pancreatitis is mediated at least in part by paracrine release of IGF-I from fibroblasts.

Characterization of MAST9/Hevin, a SPARC-like protein, that is down-regulated in non-small cell lung cancer.

In the search for genes down-regulated in non-small cell lung cancer (NSCLC), we have identified a cDNA fragment, termed MAST9. Cloning, sequencing, and characterization of the full-length MAST9 cDNA revealed that the entire 2808 nucleotide sequence had an open reading frame of 1992 nucleotides encoding a Mr 75,000 protein. Sequence analysis disclosed a striking homology to SPARC, known to be involved in tumorigenesis. The recently identified "Hevin" cDNA isolated from high endothelial venules is identical to MAST9. Using Northern and Western blot analysis, we showed that MAST9 was down-regulated in the tumor samples of nine non-small cell lung carcinoma patients. Furthermore, we demonstrated that both the bacterially expressed and the endogenous MAST9 proteins form homodimers. The lack of expression in non-small cell lung carcinomas and its homology to SPARC suggest a putative role of MAST9 in lung tumor formation.

Allelic deletion at chromosome 11p13 defines a tumour suppressor region between the catalase gene and D11S935 in human non-small cell lung carcinoma.

A previous study of 48 primary non-small cell lung carcinomas (NSCLC) for allelic loss at five polymorphic chromosome 11p loci indicated regions of allelic deletion for both 11p13 and 11p15. To further delineate the extent of this deletion 28 NSCLCs were examined by high resolution deletion mapping for allelic loss at 11p13.95% (18/28) of the informative cases displayed allelic loss at the catalase gene locus (CAT), 64% (18/28) at D11S935 and D11S941E, respectively, and 23% (6/26) at D11S907. The minimal region of deletion is bordered by CAT and D11S935 and spans about 3 cM. The relationship between allelic loss within this chromosomal region, the presence of a putative predisposition locus and the pathogenetics of NSCLC are discussed.

Differential messenger RNA and protein expression of the receptor for advanced glycosylated end products in normal lung and non-small cell lung carcinoma.

The receptor for advanced glycosylated end products (RAGE), a member of the immunoglobulin superfamily, was one of the cDNA subtraction clones that was found to be differentially expressed in human lung and the corresponding tumor tissue. In nine additional matched normal/tumor pairs, a strongly reduced or missing expression, not only on a transcriptional level but also on a protein level, was demonstrated in the non-small cell lung carcinoma tissue. Because amphoterin, a physiological ligand of RAGE that is highly expressed in the lung, mediates cell differentiation via RAGE, a down-regulation of the receptor may be considered as a critical step in lung tumor formation. Furthermore, we determined the complete reading frame of RAGE.

Identification of genes differentially expressed in normal lung and non-small cell lung carcinoma tissue.

Using a magnet-assisted subtraction technique, 17 complementary DNA (cDNA) clones were isolated that were expressed in the normal lung but were decreased or lost in the corresponding tumor tissue of a nonsmall cell lung carcinoma patient. The lack of expression of six magnet-assisted subtraction technique cDNA clones in three additional non-small cell lung carcinoma cases indicates their possible relevance for non-small cell lung carcinoma. Two cDNA clones revealed homology to genes specifically expressed in lung, i.e., pulmonary surfactant-associated protein B and the receptor for advanced glycosylation end products of proteins. Three cDNA clones showed identity to cDNA sequences encoding calmodulin-like protein, glutamine synthetase, and cytoskeletal beta-actin. One cDNA clone is identical to a recently described human expressed sequence tag whose gene is still unknown.

Multistep transformation in low-grade lymphoproliferative diseases.

BACKGROUND: Carcinogenesis, the formation of solid tumors, is now widely accepted to represent a multistep process. Several genetic events, activation of proto-oncogenes and inactivation of tumor suppressor genes, are involved. DESIGN: Review of the literature for evidence that the concept of multistep transformation has relevance also for the formation of low-grade lymphoproliferative diseases. RESULTS AND CONCLUSION: The common translocations in low-grade lymphoid tumors are probably early events, predominantly involved in the activation of oncogenes, leading to growth stimulation or prolonged cell survival. As a result 'monoclonal lymphoproliferative disorders of undetermined significance (MLDUS)' occur, undetermined, because some translocations may not always led to tumor formation. For progression to full malignancy, additional genetic events are required besides sequential selection of variant subpopulations within the neoplastic clone. Recent data indicate that mutations and deletions of putative tumor suppressor genes, including the P53 and retinoblastoma genes, are also involved in the progression of lymphoproliferative disorders. A list of lymphoproliferative diseases stressing this concept of multistep transformation is presented in this article.

Loss of heterozygosity on chromosome 11p13 in primary bladder carcinoma.

Although the occurrence of bladder cancer is common, the molecular events underlying the pathogenesis of this cancer remain ill-defined. A loss of heterozygosity (LOH) at specific chromosomal loci may predispose individuals to the development of bladder cancer but this has not been examined in detail. Furthermore, the role that deletion or inactivation of putative tumour suppressor genes might play in the genesis of bladder cancer has not been established. In this study, allelic deletion analysis on the short arm of chromosome 17 of patients with primary bladder tumours failed to show deletion at 17p13 (0/7), a region known to contain the p53 tumour suppressor gene. Chromosome 11p15 showed allelic deletion at the IGF2 locus (2/7: 29%) and the PTH locus (1/11: 9%). However, no deletion was observed at the CALCA locus (0/6). LOH at 11p13, a region containing the Wilm's tumour suppressor gene (WT1), was also studied. Analysis of LOH at 11p13 showed deletion at the CAT locus (13/18: 72%), the delta J/D11S414 locus (5/15: 33%), the WT1 locus (7/14: 50%) and the FSHB locus (6/16: 38%). The significance of these findings is discussed.

Allelic loss on the short arm of chromosome 11 in non-small-cell lung cancer.

Forty-eight samples of primary non-small-cell lung cancer (NSCLC) and normal tissue from the same patients were analyzed for allelic deletions on chromosome 11p. Five polymorphic loci were assessed to determine the incidence of 11p sequence deletions and to define hot-spots of deletions. Information was obtained from all patients in at least one locus. Our data show that the deletions observed were not randomly scattered over the short arm of chromosome 11. Rather, 2 hot-spots of deletions were observed: one in the area of the genes for catalase and beta-FSH corresponding to band 11p13, the other close to the IGF-II locus corresponding to band 11p15. A high incidence of loss of heterozygosity (LOH) was found with the probe for catalase (21/29), a locus flanking the centromeric region of the Wilms' tumor locus. Most of the samples exhibiting LOH of one or more of the alleles analyzed remained heterozygous for at least one other chromosome 11p allele. Furthermore, duplication of the intensity of the remaining allele was rarely observed. Our results indicate that LOH on the short arm of chromosome 11 is a common event in NSCLC and that the chromosomal region containing the Wilms' tumor locus is most commonly involved.

[Therapy of bronchus carcinoma: therapeutic possibilities and current molecular biology trials]. / Die Therapie des Bronchuskarzinoms: therapeutische Möglichkeiten und neuere molekularbiologische Ansätze.

Clearcut progress has been achieved in the treatment of lung cancer in the last decade. While small cell lung cancer has proven a highly chemosensitive tumor, only remissions of relatively short duration are obtained. The high relapse rate is probably due to the reappearance of chemoresistant subclones. In contrast, non small cell lung cancer is often chemoresistant from the outset, a fact which limits the therapeutic possibilities in these tumors. Different forms of chemoresistance are described and potential modalities of circumventing or reversing it are discussed. In recent years, greater insight into molecular mechanisms of tumor formation has been achieved. The role of activation or overexpression of oncogenes has been demonstrated. More recently the role of tumor suppressor gene inactivation has become evident. By means of restriction fragment length polymorphism (RFLP) a combination of gene deletions in various chromosomes has been demonstrated in lung cancer. The pattern of chromosomes involved appears to vary between small cell and non small cell lung cancer. It is to be hoped that these new insights will be translated into new treatment modalities for lung cancer.

Improved tolerance of interferon alpha-2a by continuous subcutaneous infusion.

Fifteen patients with progressing melanomas, hypernephromas or B-cell malignancies were treated in a phase I study with Interferon (IFN) alpha-2a by continuous subcutaneous infusion. With the help of a syringe driver pump daily doses of 12-15 MU resulting in median weekly doses of 90 MU could be safely given with little side effects. Flu-like symptoms and side effects from the gastrointestinal tract were mainly of grade 1 or 2 only. The major dose limiting but reversible toxicity was leukopenia. Five patients developed local inflammatory reactions at the infusion site. The pharmacokinetic data demonstrate that by this route of administration median serum levels of 54 IU/ml (range 9.6-192.0 IU/ml) (EIA-F-assay) can be achieved. Antibody formation was observed in 4 patients. - One out of 9 patients evaluable for tumor response demonstrated a partial tumor regression and 4 patients had a stabilisation of their disease. In comparison to intermittent i.m. or s.c. schedules, this novel route of administration by continuous subcutaneous infusion results in significant serum concentrations, biological activity and little clinical side effects. This may facilitate in the future the combination of IFN alpha-2a with other biological response modifiers like interleukin-2 or tumor necrosis factor.

[Possibilities and limits of the use of interferons in the clinic]. / Möglichkeiten und Grenzen der Anwendung von Interferonen in der Klinik.

Only the recent production of large amounts of highly purified recombinant interferons has made it possible to elucidate precisely the in vitro and in vivo effect of alpha- and gamma-interferon. Interferon-alpha has significantly widened the treatment modalities for some rare tumors such as hairy cell leukemia and chronic myelogenous leukemia. Although treatment results in solid tumors are disappointing, tumor regression greater than 50% is achieved in 15-25% of patients with hypernephroma or melanoma, cancers highly resistant to cytotoxic drugs. The solid tumors must be treated with high doses of interferon-alpha which causes severe side effects. Interferon-induced toxicity can be reduced by continuous subcutaneous infusion. Interferon-alpha is also used for the treatment of viral diseases such as chronic hepatitis-B, as well as for patients with AIDS and Kaposi sarcoma. Other virus infections such as herpes simplex and condylomata acuminata represent the few established indications for treatment with interferon-beta. Interferon-gamma has distinct immunomodulatory effects in vitro and in vivo, although the clinical significance of this potential has not yet been established. Thus far the treatment results in tumor patients have been poor. The future will show if the combination of interferons with other biological response modifiers, such as tumor necrosis factor or interleukin-2, or with cytotoxic drugs, brings further progress in cancer treatment.

[Infusion pumps and subcutaneously implantable catheter systems as an aid in the ambulatory care of tumor patients]. / Pumpen und subkutan implantierbare Kathetersysteme als Hilfsmittel in der ambulanten Behandlung von Tumorpatienten.

Totally implantable catheters have greatly improved therapy and supportive care of tumor patients. Venous catheters can reduce the problem of maintaining reliable vascular access and the risk of cytotoxic drug extravasation. In addition, epidural or intrathecal catheter systems can result in an improved pain relief and in reduced side effect incidences in many patients suffering from severe cancer pain. The intraarterial and intraperitoneal catheters facilitate loco-regional chemotherapy. If used by an experienced team, most of these systems have a relatively low complication rate. The combination of such catheters with portable pumps does further facilitate the management of ambulatory tumor patients and will improve their quality of life.