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p53 overexpression was present in the normal or dysplastic epithelium, but absent in the adjacent invasive cancers of five patients with head and neck squamous cell carcinomas (HNSCC), when p53 immunostaining (IHC) was performed. In three of the five p53 immunoreactive dysplasias and adjacent p53 negative invasive cancers single stranded conformation polymorphism (SSCP) results from exon 7 and 8 were also obtained. Bandshifts in exon 7 were detected in two dysplasias, and bandshifts in exon 8 were found in a third. Sequencing of exon 7 in the first dysplasia with bandshift indicated a deletion of codon 241-242 (loss of CT) resulting in a frame shift. In the second dysplasia with bandshift a mutation was observed in codon 244 resulting in a Gly-->Arg substitution in the protein sequence. In the adjacent IHC p53 negative invasive cancer lesions, no bandshifts could be observed by SSCP, and sequencing did not reveal any mutated p53. WAF1/p21 (IHC) expression was assayed to study p53 function. Image cytometry (ICM) DNA analysis, estimating genetic instability, showed progress in DNA aberration for invasive cancer lesions as compared with the dysplasias. Human papillomavirus (HPV DNA) was not detected by a polymerase chain reaction (PCR) in any of the five cancers thus excluding possible p53 degradation caused by HPV protein. In conclusion, the finding of p53 mutations in mild, moderate, and severe dysplasia indicates that p53 mutation, not only p53 immunoreactivity, can be an early event in HNSCC carcinogenesis. The lack of p53 immunoreactivity in the invasive cancers adjacent to p53 positive dysplasias could possibly be attributed to loss of the mutant allele, or clonal heterogeneity.

Many studies have noted an association between amplification of single oncogenes and poor prognosis in breast cancer. We are investigating whether measurement of amplification in a larger number of proto-oncogenes increases the reliability of the prognostic information provided. As the first stage of this investigation, amplification (of c-erbB-2, cycD1, int-2, c-myc and MDM2), aneuploidy and altered expression of p53, which all indicate genetic instability, were studied in 117 primary breast adenocarcinomas. Amplification was correlated with aneuploidy (p=0.002) but not with altered expression of p53 even though the tumours with p53 overexpression were all aneuploid. Our results suggest that measurement of amplification is a potentially valuable prognostic factor.

Acute but not delayed nausea is well controlled by serotonergic receptor-antagonists implicating different mediation of delayed as compared to acute nausea and vomiting. We report on differences in central neural activity using positron emission tomographic (PET) measurements of regional cerebral blood flow (rCBF) in two chemotherapy treated cancer patients during delayed severe and mild nausea. Subtractive image methodology where rCBF during moderate nausea was subtracted from rCBF during mild nausea revealed increased neural activity in the anterior hypothalamus, the vermis, the anterior cingulate gyrus and the thalamus as well as decreased activity in the pens and the substantia nigra. These results may reveal central nervous system substrates underlying delayed nausea and vomiting and are consistent with an interpretation in terms of activation both of serotonergic and noradrenergic but not dopaminergic transmitter systems. It is concluded that noradrenergic mediation of delayed nausea is not an unlikely possibility.

Although several oncogenes and tumor suppressor genes have been suggested to be of relevance for the development of oral cancer, it is likely that additional genes are involved in this complex process. Therefore, in an attempt to isolate such genes, the aim of this study was to investigate changes in gene expression in human buccal carcinoma cells as compared to normal buccal epithelial cells, and identify mRNA overexpressed in the carcinoma cell line. The method of differential display of mRNA was used to isolate differentially expressed genes (Liang P et al, Science 257:967-971, 1992). A key step of this method, a polymerase chain reaction amplification, was optimized in terms of choice of thermostable DNA polymerase, annealing temperature, molar ratios and concentrations of primers. The comparative analysis of expression in tumor and normal buccal epithelial cells led to the isolation of three different mRNAs overexpressed in human oral carcinoma cells, as confirmed by Northern blot analysis. Cloning and sequence analysis revealed that these genes, which were termed OTEX as in Oral Tumor EXpressed, included a novel, previously not characterized, human gene, OTEX-1. OTEX-2 was identical to the gene coding for the L26 ribosomal protein, a protein known to be overexpressed also in other tumor cell types. OTEX-3 showed a perfect match to a sequence isolated during the human genome sequencing project, with a hitherto unknown function.

In this investigation, the in vitro production of progesterone and estradiol in ovarian tissues was studied for the first time in relation to the immunohistochemical expression of steroid hormone receptors, Ki-67, p53, DNA ploidy and S-phase fraction. Ovarian tissue from 44 women was examined. Steroid receptors were found more frequently in normal than in tumor ovaries. A substantial focal staining heterogeneity was demonstrated. Mucinous tumors were always progesterone receptor negative. Furthermore, the Ki-67 index was negatively correlated to the progesterone production of the tumor ovaries. Among the malignant tumors, all the high producers of progesterone expressing PR were low proliferating, diploid and p53-negative.

Serum levels of squamous cell carcinoma antigen (SCC), carcinoembryonic antigen (CEA), CA 125 and tissue polypeptide antigen (TPA) were serially determined in 116 patients with cervical carcinoma. Serum levels of SCC or TPA levels were elevated in the 12 patients with residual tumour after primary therapy. In patients who were clinically in complete remission, SCC and TPA levels were elevated in 7/69 and 5/70 patients, respectively. Three of the 7 with positive SCC and 4 of the 5 patients with positive TPA levels had a recurrence during follow-up. Elevated levels of SCC or CA 125 or TPA preceded the clinical detection of recurrence in 13 of 18 patients (median time was 7 months for SCC and 6 months for CA 125 and TPA).

We investigated to clarify the mechanism of action of AK-2123. V79 cells were used, and the effect of the substance was estimated with different end-points viz. induction of DNA breaks, micronuclei and clonogenic survival after hypoxic irradiation with different X-ray doses. After treatment with 0.1 mmol dm(-3) of the substance, sensitization by a factor of 1.8, 1.1 and 1.4 respectively, was calculated. By determining the enhancement ratio after treatment with the drug at 7-8 different concentrations varying between 0.001 and 50 mmol dm(-3), the concentration of the substance for half of the maximum sensitization (K-value) was estimated to be 40 mu mol dm(-3) (DNA breaks), 1200 mu mol dm(-3) (micronuclei) and 2000 mu mol dm(-3) (survival); the maximum sensitizer enhancement ratio was 2.4 (DNA breaks), 2.3 (micronuclei) and 2.4 (survival). No cytotoxic effects were found when the cells were treated with the drug in different concentrations for 30 minutes. However, after longer periods the compound was found to be cytotoxic both under aerobic and hypoxic conditions, in a concentration and time dependent manner. A post-irradiation enhancement of the sensitivity was noted when the drug was left in the medium for 24 hours after hypoxic as well as aerobic radiation exposure.

We show that transformation of rat CREF fibroblasts by adenovirus-2 early regions 1A and 1B (E1) is stimulated by expression of the viral early region 4 (E4) products. Cotransfection of CREF cells with E1 and E4 did not affect the number of E1-transformed foci, but resulted in the formation of larger and more dense foci compared to E1 transfection alone. Cells obtained from these foci were capable of anchorage-independent growth. The adenovirus-2 E4 region encodes for a minimum of seven proteins, several of which have been shown to have distinct biological activities. To assay for the activity of these individual proteins on E1 transformation, we used expression vectors designed to encode single E4 proteins in the CREF cell transformation assay. By this strategy, we could show that two E4 proteins had a significant capacity to stimulate E1 transformation. Cotransfection of E1 and vectors encoding the E4-ORF1 or E4-ORF6 proteins resulted in the formation of large dense foci typical of E4-cotransformed cells. However, no single E4-ORF-expressing plasmid was sufficient to reproduce the stimulative effect on CREF cell transformation observed using the entire E4 region.

We here report a unique intron deletion in the p53 gene. Analysis of a human tonsil tumor that expressed elevated levels of p53 showed a deletion of the entire intron 7 in one of the p53 alleles, leaving the coding sequence intact. The significance of the intron 7 deletion for the development of the tonsil tumor is discussed.

EGF-like activity was measured in media from 3-hour incubations of ovarian tissue from 27 patients with normal postmenopausal ovaries, malignant or benign epithelial tumours. EGF-like activity in the medium was measured using a radioreceptor assay. Malignant tumour tissue released significantly more EGF/TGF-alpha than benign tissues and aneuploid carcinomas more than diploid carcinomas. In spite of varying amounts of tumour cells there was a strong correlation in EGF/TCF-alpha release from the different tissue samples of each patient suggesting paracrine rather than autocrine regulation. The level of EGF-like activity may be a feature of the patient rather than of the tumour cells.

Expression of the growth suppressor gene p53 in Schizosaccharomyces pombe causes growth arrest which can be suppressed by overexpression of a yeast gene termed tms1. The tms1 gene encodes a 37 KDa protein which binds to p53 in vitro and in vivo when p53 was expressed in fission yeast cells. By using antibodies against recombinant tms1 protein we analyzed mammalian cells for the expression of a tms1 related protein. Human, monkey and rat cells exhibited a bright nuclear fluorescence when incubated with the tms1 specific antibody. In addition, we were able to specifically immunoprecipitate a 42 KDa protein which forms complexes with the p53 protein. The specificity of these complexes was demonstrated by coimmunoprecipitation using different monoclonal antibodies against p53, antibodies against yeast tms1 as well as by Western blot analysis. Thus, we found that the mammalian tms1 related protein represents a new p53 binding protein.

To study psychological effects on the immune system, a saline infusion was administered to 24 fully informed patients who previously had received adjuvant chemotherapy for breast cancer. Blood samples were drawn before and after treatment, and compared to samples obtained at home two days earlier. Patients displayed a rise in natural killer-cell activity and a tendency to lowered percentage of suppressor/cytotoxic cells when assessed before treatment as compared to at home. Trait anxiety was associated with numbers of leukocytes. It is concluded that immune status partly reflects psychological factors.

A cohort of asbestosis patients at high risk for cancer was investigated by the means of epidermal growth factor receptor and Neu oncoprotein levels in serum. The samples were collected between 1981 and 1987 from 111 asbestosis patients. X-ray pictures, taken three times during this period of time, were evaluated according to the ILO classification to deduce the severity of the disease (stable, unstable) and compared side by side to determine the progression of asbestosis. Follow-up of these patients until 1993 showed that 38 patients had developed cancer (27 lung, 3 pleural mesothelioma, 8 diverse malignancies). As determined by ELISA for EGFR and two different assays for Neu oncoprotein (Neu, nNeu) there was a statistically significant difference between EGFR levels in all the cancer and the non-lung cancer cases compared with the controls. No statistically significant differences were detected between Neu levels in the cancer cases and the controls. Protein concentrations showed no change prior the diagnosis of cancer. The serum levels of the proteins correlated with each other (EGFR-Neu, r=0.3; Neu-nNeu, r=0.7). Among 9 factors that were analyzed by multiple regression analysis progressive asbestosis was statistically significantly associated with the elevation of Neu and smoking with the elevation of nNeu. In logistic regression analysis only unstable asbestosis associated with cancer (OR = 6.25, p=0.0012). This study shows a coherence between the severity of asbestosis and development of cancer. Furthermore, the Neu concentration in the serum was elevated in both unstable and progressive asbestosis cases and may offer tools, supplementary to X-rays, for clinical monitoring of the pneumoconiosis patients.

Kaposi's sarcoma (KS) was up to the 1980's seen as a rare indolent sporadic disease in Southern Europe and as an endemic disease in East and Central Africa. With the onset of the HIV/AIDS epidemic a more aggressive, disseminated type of KS was recognized in HIV infected people with AIDS. Interestingly, KS has not been reported in Indians living in Africa for several generations. Recently KS was however, diagnosed in two Tanzanian Indians, both infected with HIV. Clinical and pathological studies of these two cases showed the characteristic hallmarks of KS in both HIV infected and uninfected people. From the literature and cancer registry data it appears that KS has been even more rare in India and other Far Eastern countries, compared to Europe and the Americas, with only a few cases reported with and without HIV association. The present data and that reported earlier in the literature support the notion of an infectious agent transmitted sexually in the pathogenesis of KS. Ethnic/genetic factors could also be of importance.

We prospectively studied, how certain patient characteristics modify the risk of chemotherapy induced and conditioned nausea and vomiting. Young age and previous history of nausea and vomiting were factors associated with both chemotherapy induced nausea and vomiting as well as conditioned nausea. Conditioned nausea was significantly associated with having received two-day compared to one-day mode of chemotherapy, previous distress during blood samples and odor memory. Tentative associations were also found between a history of flushing and chemotherapy induced nausea and vomiting as well as between autonomic perception, odor associations and conditioned nausea. The investigated variables explained a larger part of the variance in conditioned compared acute nausea and vomiting.

The radiosensitizing effect of AK-2123, a 3-nitrotriazole, and of misonidazole, a 2-nitroimidazole, was studied on hypoxically irradiated Chinese hamster cells (V79-379A) with DNA damage as end-point. The damage was estimated with the alkaline unwinding assay and the DNA precipitation technique, carried out in parallel or in separate experimental series. The sensitizers were used in different concentrations together with standard radiation doses of 30, 60 and 90 Gy. Sensitizer-untreated cell cultures served as controls. The data indicated a radiation dose-dependent sensitization when the effect of AK-2123 was tested with the two assays, the lower radiation dose being associated with larger sensitization. In contrast, sensitization was found to be dose-independent when the effect of misonidazole was tested.

Nine cell lines were isolated after cotransfection of rat embryo fibroblasts with polyomavirus large-T (plt) and T24-ras oncogenes. Five of these lines were highly tumorigenic following subcutaneous injection, but differed in their metastatic and in vitro invasive properties. Two cell lines, expressing low levels of ras mRNA, showed low capacity for experimental metastasis. Three cell lines, expressing high levels of ras mRNA, were tumorigenic and showed high capacity for experimental metastasis. High expression of interstitial collagenase, stromelysin and 92 kDa type IV collagenase was observed in the highly metastatic cell lines. Immunochemical analysis revealed that these cell lines expressed apparently wild-type p53 protein. Furthermore, the level of a 43 kDa/pI 5,44 polypeptide was elevated and the levels of a series of 41 to 43 kDa acidic polypeptides were decreased in the metastatic cells. Within this panel of transformed cell lines, high capacity for experimental metastasis did not correlate with high chemoinvasive capacity in the reconstituted basal membrane assay. The limited invasive propensity could not be attributed to low chemotactic or adhesive capacity. We conclude that in vitro invasion does not correlate with experimental metastasis in this model system.

Treatment with mevinolin (an HMG CoA reductase inhibitor) blocks proliferation and causes characteristic morphological changes in human breast cancer cells (MDA231). In this study we demonstrate that the conditioned medium of these cells contains factors that stimulate DNA synthesis and normalize morphology in mevinolin-treated cells, without reducing the inhibition of HMG CoA reductase activity. These data suggest that the breast cancer cells produce and release mevalonate-derived products which influence DNA synthesis and morphology. By undertaking a simple purification of the conditioned medium we could demonstrate that the effects on DNA synthesis and morphology were mediated by different compounds.