Characterization of glycolipids from the gastric cancer of a patient of p,O,Le(a-,b+) blood type: presence of incompatible blood group antigens in tumor tissues

The antigens present in a gastric tumor obtained from a patient of blood group p,O,Le(a-,b+) were studied. The neutral glycolipids were isolated from the cancer tissues and characterized chemically and immunologically. The glycolipid pattern of the tumor was similar to that of the surrounding uninvolved mucosae. The major neutral glycolipids were found to be glucosylceramide, galactosylceramide, lactosylceramide, and the lacto series glycolipids, including the H, Lea, and Leb active fucolipids. The cancer tissues and the uninvolved mucosae did not contain galabiosylceramide, globotriaosylceramide, or globotetraosylceramide after separations by both thin layer chromatography and gas-liquid chromatography. Thin layer chromatography immunostaining was performed to detect incompatible blood group antigens. Immunostaining revealed the presence of globotriaosylceramide, globotetraosylceramide, Forssman glycolipid, and A active glycolipids in the cancer tissues. These incompatible blood group active glycolipids were absent from the uninvolved mucosae. The results indicate that the cancer tissues possess the ability to produce the globo series of glycolipids and the A active antigens but that the surrounding uninvolved mucosae could not synthesize these glycolipids.

Enhanced expression of c-Ha-ras p21 in human stomach adenocarcinomas defined by immunoassays using monoclonal antibodies and in situ hybridization

Using c-Ha-, c-Ki-, and c-N-ras-specific probes in a RNA-RNA hybridization assay we found enhanced expression of c-Ha-ras protooncogene in stomach adenocarcinomas relative to nonneoplastic epithelium, whereas little or no transcription of either c-Ki- or c-N-ras was detected. Enhanced levels of c-Ha-ras RNA expression were detected in all of the adenocarcinomas examined. Hybridization with c-Ha-ras was also detected in nonneoplastic gastric epithelium adjacent to carcinoma, although the labeling was less intense than that of carcinoma cells. More extensive analysis of the c-Ha-ras p21 expression was then carried out in formalin-fixed, paraffin-embedded tissue sections and extracts from surgically resected stomach tissues using monoclonal antibodies (MAbs) RAP-5 and Y13-259. The data obtained from the immunohistochemical studies were consistent with the results of in situ hybridization assay. Adenocarcinomas were much more reactive with MAb RAP-5 than benign and normal tissues, and the majority of carcinomas demonstrated increased expression of c-Ha-ras p21. Quantitative liquid competition radioimmunoassays using MAb Y13-259 also demonstrated significantly higher levels of c-Ha-ras p21 in extracts from stomach adenocarcinomas than those from normal mucosae. No strict correlation was found between ras p21 expression and the degree of tumor differentiation or histological type. Although advanced carcinomas generally demonstrated higher levels of ras p21 than early carcinomas, no correlation among advanced carcinomas and ras p21 levels was observed in relation to depth of tumor invasion to the muscularis propria, subserosa, or serosa. Benign lesions, in comparison, were much less reactive with MAb RAP-5 than carcinomas. Among the benign lesions tested, dysplastic lesions were more reactive than nondysplastic lesions. Normal stomach mucosa was generally nonreactive with the exception of parietal cells. Our results indicate that transformation of the stomach mucosa from benign to malignant phenotype is associated with an increase in c-Ha-ras p21 expression.

[Evaluation of the prognostic factor in human gastric cancer with special reference to the relationship between proliferation and carcinoembryonic antigen production of the cancer cell]

The biological property of human gastric cancer was studied by morphological and immunohistochemical observations. The cytoplasmic mucin of cancer cells was mainly neurtromucin in the mucosa. However, acid mucin was increased in the cancer cells of signet-ring cell carcinoma with submucosal infiltration. Immunohistochemically, CEA was localized in the plasma membrane of matured signet-ring cells and the cytoplasm of immature cancer cells. On electron microscopic observation, the cytoplasmic organellae were prominent in the immature cells which were dominant in submucosal infiltrating region. In vitro, the cancer cell line established from signet-ring cell carcinoma revealed that CEA production was associated with cell growth property showing 3H-TdR and BrdU uptake. This results may suggest that CEA production was an important indicator for the decision of prognosis in signet-ring cell carcinoma.

Serotonin in tubular adenomas, adenocarcinomas and endocrine tumours of the stomach. An immunohistochemical study

Serotonin was examined immunohistochemically in seven tubular adenomas, 194 adenocarcinomas and 41 endocrine cell tumours of the stomach. In tubular adenomas, serotonin-containing cells showing argentaffinity were present in the lower portion of the adenomatous glands and were considered to be an expression of intestinal character. Scattered serotonin-containing tumour cells were found in 60 (30.9%) of 194 adenocarcinomas regardless of their histological type. Cell fusions between carcinoma and enterochromaffin (EC) cells might be a possible mechanism for the occurrence of serotonin-containing cells within the tumour. In 17 (54.8%) of 31 endocrine cell carcinomas, serotonin-containing tumour cells were observed in a variable degree in contrast to the absence of these cells in classical carcinoid. Moreover, diffuse serotonin reactivity was found in four cases of scirrhous endocrine cell carcinoma. The histogenesis and the occurrence of serotonin-containing cells in each type of gastric tumour is also discussed.

A somatostatin receptor negatively coupled to adenylate cyclase in the human gastric cell line HGT-1

Somatostatin receptors are demonstrated in the human derived gastric cell line HGT-1. Using 125I-Tyr11-somatostatin as ligand, two classes of sites were characterized with apparent dissociation constants KD1 = 0.9 X 10(-10) M and KD2 = 4 X 10(-9) M and maximum binding capacities of N1 = 20 and N2 = 556 fmol per mg protein, respectively. These values are close to those previously reported in freshly isolated parietal cells (Reyl, F., Silve, C. and Lewin, M.J.M., Somatostatin receptors on isolated gastric cells. In S. Bonfils et al. (Eds.), Hormone Receptors in Digestion and Nutrition, Elsevier/North-Holland, Amsterdam, 1979, pp. 391-400). Somatostatin binding to the high affinity sites was partially inhibited by the non-hydrolysable guanyl nucleotide analog Gpp(NH)p and by pretreating the cells with islet activating protein (IAP). Furthermore, IAP counteracted the inhibitory effect of somatostatin on histamine stimulation of adenylate cyclase. These findings are interpreted in terms of somatostatin interaction with the 41,000 Da adenylate cyclase GTP-dependent inhibitory subunit, Ni.

Cell cycle kinetics responses of human stomach cancer cells to reduction in polyamine levels by treatment with alpha difluoromethylornithine in vitro

Treatment of human gastric cancer clones in vitro with low doses of DFMO (5 mM) produced elongation of the cell population doubling times and lowering of the saturation densities. By contrast, DFMO treatment of normal human skin fibroblasts altered only the saturation density. The lack of an effect of 5 mM DFMO on the doubling time of normal fibroblasts may be directly related to baseline intracellular putrescine levels, which were about 2.5 times higher than in the cancer cells. The same dose of DFMO caused a rapid decrease in intracellular polyamine levels in the tumor clones. The effects on the doubling time and saturation density were almost totally abolished by the addition of 50 microM putrescine to the growth medium during the first 24 h of treatment with DFMO. Exposure to 5 mM DFMO for 24 h caused the human gastric cancer cells to become blocked in G1 phase only, and this led to a reduction in the fraction of cells in S phase. The G1 block was reversible and this cohort of cells eventually passed through S phase and then through G2 and M. A higher 100 mM dose of DFMO and longer exposure times for both doses produced cell cycle changes and death of more than 90% of the cell population. These data suggest that cell kinetics changes observed under these experimental conditions may reflect polyamine-related alterations in the biochemical events of cell cycle progression kinetics; but may also be the result of DFMO-induced loss of cell viability.

Heterogeneous survival responses of human gastric cancer clones to alpha difluoromethylornithine in vitro

The effects of alpha Difluoromethylornithine (DFMO)2 on survival of human gastric cancer clones were studied in vitro. The responses were dose and time dependent. Treatments which lasted for less than 12 h were cytotoxic at only the highest doses used. The greatest effects on survival were observed only when cells were treated for 48 and 72 h. The effects on the clones produced by such prolonged treatment durations were heterogeneous, with survival values differing by as much as 460%. By contrast, the clonal survival responses to short DFMO treatments (12 h) were very uniform (dose differential of only 19%); however, this uniformity in response could be achieved only by using non-pharmacological doses of DFMO. The heterogeneity in survival responses in the clones might be slightly associated with their levels of intracellular spermidine. Clones with the smallest amounts of intracellular spermidine at the start of treatment were most sensitive to DFMO. However, this association may not hold up with further testing in other gastric cancer clones or when studied in other cancer lines in vitro.

[Immunohistochemical study of oncogene-related products in human gastrointestinal malignancies--expression of ras p 21, fes p 85 and EGF receptor]

An immunohistochemical examination by the avidin-biotin-peroxidase complex method was carried out to assess the expression of oncogene-related products, i.e., ras p 21 protein, fes p 85 protein and epidermal-growth-factor (EGF) receptors, in human gastrointestinal malignancies. The presence of ras p 21, fes p 85 and EGF receptors was detected in 48%, 62%, and 62% of 29 colorectal carcinomas and in 65%, 65% and 40% of 20 gastric cancers, respectively. More than one oncogene protein was demonstrated in 18 of 29 colorectal carcinomas and in 10 of 20 gastric cancers. These results suggest that multiple oncogenes are important in the occurrence and progress of gastrointestinal malignancies.

Tumor-associated glycoprotein (TAG-72) detected in adenocarcinomas and benign lesions of the stomach

Murine monoclonal antibody (MAb) B72.3, prepared against a membrane-enriched extract of metastatic carcinoma and reactive with a high-molecular-weight determinant, designated tumor-associated glycoprotein (TAG)-72, was shown to be reactive immunohistochemically with 97% of a variety of primary adenocarcinomas of the stomach (n = 40). All "early" gastric carcinomas were reactive with MAb B72.3, although the average percentage cellular reactivity was lower than in "advanced" carcinomas. TAG-72 antigen was detected in benign lesions (i.e. adenomatous polyps and hyperplastic polyps) with intestinal metaplasia. Dysplastic lesions characterized by cellular atypia, abnormal differentiation, and disorganized mucosal architecture demonstrated higher TAG-72 expression than non-dysplastic epithelia. In contrast, normal gastric mucosa was generally non-reactive with MAb B72.3. Assays using serial sections of normal, benign and malignant gastric tissues with two MAbs (B1.1 and COL-6) directed against distinct epitopes of carcinoembryonic antigen (CEA) demonstrated differential reactivity, confirming that TAG-72 and CEA are distinct, non-coordinately expressed antigens. Our results suggest that TAG-72 antigen may be expressed in malignant and dysplastic epithelial cells, as well as in intestinalized epithelium of the stomach which has been closely related to subsequent carcinoma development. Hence, MAb B72.3 may be a useful immunohistochemical adjunct for detecting early foci of adenocarcinomas and premalignant lesions of the stomach.

[Cell kinetics and histological types of gastric cancer as studied by DNA-RNA cytofluorometry after acridine orange fluorescence staining]

In order to clarify the relation between histological classification and biological behavior of individual tumor cells, we quantitatively analyzed the cell kinetics of 56 advanced gastric cancers using DNA-RNA cytofluorometry after acridine orange fluorescence staining and compared the results with histological findings. The gastric cancers examined could be classified into two main groups based on the ploidy patterns constituting the cell population kinetics. In group I, tumor cells were found to be chiefly composed of diploid cells with many S-phase cells even at their advanced growth stages, and their morphological characteristics were shown to correspond to undifferentiated carcinoma (according to Nakamura & Sugano). In group II, tumor cells were composed of various classes of polyploid cells as well as of diploid cells with an increased number of S-phase cells, and the extent of polyploidization appeared to progress with the growth of the tumor. The morphological characteristics of this group tended to correspond to differentiated adenocarcinoma. It is, therefore, concluded that both the histological structures and cell morphology have close relationships with cell kinetics in the human gastric cancers.

DNA flow cytometry of histological material from dysplastic lesions of human gastric mucosa

DNA flow cytometry has been carried out on histologically processed human gastric tissue showing varying grades of gastric dysplasia, intramucosal carcinoma and regenerative changes. No cases of DNA aneuploidy were encountered in cases showing regenerative changes or mild or moderate dysplasia. DNA aneuploidy was found in 5/7 cases of severe dysplasia and 3/11 cases of intramucosal cancer. Irregularities of the G0/G1 peak were encountered in a further 18 samples including normal and regenerative gastric mucosa. However these were not thought to indicate DNA aneuploidy. The interpretation of these abnormalities and the affect on the frequency with which DNA aneuploidy is reported in pathological lesions is discussed.

Sialylated Lewis determinant CA 19-9 in benign and malignant gastric tissue

The expression of the carbohydrate antigen CA 19-9 in human gastric mucosa was studied by using the monoclonal 1116 NS 19-9 antibody, immunohistochemical ABC staining technique and formalin-fixed, paraffin-embedded biopsy specimens. Among 26 gastric carcinoma (GCA) patients CA 19-9 antigen was found in 16 patients (62%). The antigen was also found in 10 (48%) out of 21 non-cancer patients who had benign gastric ulcer and in 9 (12%) out of 74 non-ulcer, non-cancer patients. In non-cancerous mucosa, the CA 19-9 antigen was localized in the surface epithelium (foveolar type of staining) and/or in goblet cells and sometimes in absorptive epithelium of metaplastic intestinal glands (goblet cell type). The foveolar type but not the goblet cell type was related to the nonsecretor status of the subject, to Le positivity and to anti-H negativity of the gastric surface epithelium. It is concluded that, although being commonly present in GCA tissue, the expression of the antigen in benign gastric tissue is too common to advocate the practical value of CA 19-9 in predicting malignant gastric lesions in immunohistochemistry.

Gastric carcinoma in the young: a clinicopathological and immunohistochemical study

Seventeen patients 40 yr of age and less with gastric carcinoma were studied retrospectively. Clinicopathological findings and survival data were collected on all patients. Immunohistochemistry for serotonin, gastrin, somatostatin, carcinoembryonic antigen, beta-human chorionic gonadotropin, and alpha-fetoprotein was performed and the results correlated with pathological and survival data. Patients were divided into two groups according to the presence or absence of endocrine markers in their tumors. The group with endocrine immunoreactivity tended to present with less advanced disease and had longer survival than the group without endocrine immunoreactivity (p less than 0.05). Although the number of patients in the study is too small to reach definite conclusions, our results are interesting in light of current knowledge of the pathobiology of gastric carcinoma and have important implications for future investigations.

[Prostaglandin E (PGE) and gastric carcinoma]

Since 1984, an experimental and clinical study on the relation between PGE and gastric carcinoma has been performed by determining PGE content in the bioptic gastric mucosa and plasma. It is found the PGE content in the gastric mucosa and plasma is increased in all patients with gastric cancer, especially with signet ring cell carcinoma. It is higher in the regional lymph node metastasis than in the early cancer, extensive metastases and normal subjects. The PGE content in the plasma is reduced obviously 7-10 days after operation but is increased markedly in recurrent patients. There is no significant difference in extensive metastases, relapse free and normal subjects. The PGE content in the plasma is significantly higher in gastric carcinoma than in chronic atrophic gastritis, but no difference is present between chronic atrophic gastritis and normal subjects.

[O6-methyldeoxyguanosine in DNA of the adjacent epithelium in human esophageal cancer in Linxian County]

Radioimmunoassay of monoclonal antibodies against O6-methyldeoxyguanosine (O6-MedG) was used to detect the presence of these DNA adducts in the human esophageal epithelium. The analysis comprised 48 adjacent epithelial specimens of the esophageal and cardiac cancer resected in Linxian County and 30 specimens of the fetal esophageal epithelium and 4 of the normal esophageal epithelium from autopsy as collected from the hospital in Beijing. The results show that O6-MedG was detected in all the specimens from the esophageal and cardiac cancer patients. In 7 samples in the adjacent epithelium of esophageal cancer, the level of O6-MedG ranged from 0.5 to 1.0 pmol/mgDNA. 19 showed higher levels up to 37.4 pmol/mgDNA with a mean of 4.72 +/- 6.08 pmol/mgDNA. 5 samples of gastric mucosa showed the level of O6-MedG ranging 0.3-1.0 pmol/mgDNA and the remaining 6 showed a higher level of 1.2-13.4 pmol/mgDNA. The mean was 3.31 +/- 3.97. In all the 11 patients, O6-MedG was detected in the para-cancerous gastric mucosa of the cardiac cancer. 4 normal autopsied esophageal epithelial samples were too low for detection. Samples from the fetal esophageal epithelium showed lower level of O6-MedG, the mean was 0.4 +/- 0.57 pmol/mgDNA. The results mentioned above give us the new evidence that the effect of N-nitrosamines is most likely a causative factor in the carcinogenesis of human esophageal cancer.

Histologic demonstration of antigens reactive with anti-p21 ras monoclonal antibody (RAP-5) in human stomach cancers

The immunohistochemical reactivity of RAP-5, a monoclonal antibody (MoAb) raised against a synthetic peptide corresponding to positions 10-17 of the ras gene product from T24 bladder carcinoma, was studied in 96 surgically resected stomach cancers of humans. The cytoplasm of cancer cells in 65 cases (68%) was positively stained with MoAb RAP-5, although the staining was heterogeneous among cancer cells. There was no definite correlation between depth of tumor invasion and reactivity to MoAb RAP-5. Cancer cells of poorly differentiated tumors showed a tendency to react less frequently and less intensely to MoAb RAP-5. In nontumorous gastric mucosa, parietal cells and some portions of intestinal metaplasia were stained with MoAb RAP-5. These findings suggest an increased expression of the ras gene product (p21) in about two-thirds of gastric adenocarcinomas and in some nonneoplastic gastric epithelial cells.

[Endocrine therapy of scirrhous carcinoma of the stomach]

Tissue localization of endogenous estrogens (estrone; E1, estradiol; E2, estriol; E3) progesterone was examined in scirrhous type of gastric cancer by the peroxidase-antiperoxidase (PAP) immunoperoxidase method. Twelve of 47 specimens showed positive estrogen staining, and 4 of 47 showed positive progesterone staining. The incidence of positive staining for these 4 substances was higher in male patients than in female patients. The number of specimens with positive E2 staining was the highest among E1, E2 and E3 staining. Prognosis of patients who had undergone curative surgery with positive estrogen staining were better than that of patients with negative estrogen staining. The existence of estrogen receptor (ER) and progesterone receptor (PgR) was also shown in 3 specimens and one specimen, respectively, from another 15 specimens with scirrhous type of gastric cancer by the dextran-coated charcoal assay. In a clinical test, Tamoxifen administered patients with scirrhous carcinoma following curative or noncurative gastrectomy showed better prognosis than non-Tamoxifen administered those.

[Induction of Ca2+ ion transport in human thrombocytes as affected by thyroid hormone receptors from malignant transformed cells]

The effect of thyroid hormone receptors isolated from normal and malignant cells on the induction of Ca2+ transport to platelets was studied. It is established that the receptor isolated from malignant cells by thyroxin (T4) or triiodothyronine (T3) stimulates (three-fold) the induction of Ca2+ transport to platelets. The effect is blocked by verapamil, which is the inhibitor of Ca2+ channels in plasma membranes. It is shown that neither the receptor of cancer cells, nor hormones (T3 or T4) influence the transport of Ca2+ to platelets without preliminary complexing. The hormone-receptor complex failed to affect the concentration of "cytoplasmic" Ca2+ in platelets analogous experimental conditions. It is suggested that the increased Ca2+ content in cancer cells can be partially attributed to the ability of thyroid hormone receptor of cancer cells to induce Ca2+ transport across the plasma membrane.

[5-FU concentration in the blood and tissue of patients with gastric and colorectal cancer after administration of UFT or tegafur]

UFT or tegafur (5, 7.5 and 15 mg/kg, respectively) were given to Donryu rats with AH-130 cancer twice a day for 3 days, and 5-FU concentrations in the blood, tumor, normal stomach and large bowel tissues were measured by chemical assay and compared. The 5-FU concentrations in the tumor were higher than those of normal tissues and still remained 12 hours after the final dosage. According to increased UFT dosage, there were significantly higher levels of 5-FU concentration in tumor tissues but blood levels of 5-FU were low. The peak of concentration occurred at one to two hours after the final dosage. However, increase in tegafur dosage volume did not correlate with 5-FU levels. Clinical cases (74 patients) of gastric and colorectal cancer were orally administered UFT or tegafur at 300 mg twice a day for 3 days preoperatively. Materials were obtained at surgery at 5.5 hours on average after the final dosage and 5-FU levels in tissues were measured by chemical assay. Concentrations of 5-FU in cancerous tissues after UFT administration were 0.177 +/- 0.131 micrograms/g in gastric cancer and 0.130 +/- 0.051 micrograms/g in colorectal cancer, while in patients to whom tegafur had been administered, the concentrations were 0.194 +/- 0.124 micrograms/g and 0.119 +/- 0.075 micrograms/g, respectively. There was no significant difference in 5-FU levels between the UFT-administered group and the tegafur group.