Immunohistochemical detection of c-myc oncogene product in human gastric carcinomas: expression in tumor cells and stromal cells

c-myc protein p62 in human gastric carcinomas was studied by immunohistochemistry using an antiserum raised against the C-terminal portion of the human c-myc gene protein. No immunoreactivity of c-myc p62 was detected in tumor cells of 27 early carcinomas, while c-myc p62-positive tumor cells were observed in 51 (36.4%) of the 140 advanced carcinomas. Many stromal cells including macrophages and fibroblasts around the tumors showed various degrees of c-myc p62 immunoreactivity. Localization of c-myc p62 was predominant in the cytoplasm of tumor cells and stromal cells. The prognosis of patients with p62-positive stromal cells was significantly better than that of patients with p62-negative stromal cells.

[Comparative studies on the DNA content of human gastric cancer cells and its metastatic foci]

Comparative cellular DNA content measurements have been done on two sites differing from each other in their anatomical location, in 16 cases of gastric cancer by means of microphotometry. In addition, comparisons on the DNA stemline of the original gastric lesions and their metastatic lesions (8 cases of liver metastases and 9 cases of lymph node metastases) also were done. The main stemlines in four cases (25%) out of 16 gastric cancers exhibited different main DNA stemlines from the other sites in the same lesion, although in the other 12 cases examined, two sites showed the same DNA stemlines to each other. In almost all cases, the DNA stemlines of the metastatic foci were consistent with those of the original lesions. The lymph node metastases simulated the original lesions in its DNA stemlines (89%) more than did the cases of livermetastases (63%). In an exceptional case, the original lesion exhibited two definite stemlines (2C & 3.5C), but only one (2C) was recognizable in the metastatic focus of the liver. This difference indicates the probable role of "clonal selection" in a blood-borne metastasis.

Histochemical study of mucosubstances in carcinoma of gastric remnant

Twenty patients with carcinoma of the gastric remnant after surgery for benign disease have been studied. The histologic and histochemical data on gastric mucosa surrounding the carcinoma have been compared with data from 60 biopsy samples taken from gastric stumps without carcinoma in an age-and sex-matched group. There was a high incidence of intestinal metaplasia in the gastric stumps (24 of 60); it was even higher in the cases with a carcinoma (17 of 18). Intestinal metaplasia Type III, which is closely related to the carcinoma in a stomach not surgically treated, was rare in cases of cancer in the gastric stump (1 in 18). This finding is correlated to the high frequency of the diffuse type of carcinomas that occur in the gastric stump (15 of 20), which are rarely associated with intestinal metaplasia. Therefore, identifying intestinal metaplasia types does not always point to the fact that affected patients will also be at high risk for cancer in their gastric remnant.

Preferentially expressed genes in stomach adenocarcinoma cells

cDNA clones complementary to mRNA of neoplastic cells of human stomach tissue were used to examine quantitative changes in the mRNA levels of specific genes in neoplastic cells. Poly(A)+ RNA from poorly differentiated adenocarcinoma cells of a female patient with stomach cancer was used for construction of a complementary DNA (cDNA) library. Screening of the 18,000 colonies utilizing 32P-cDNAs derived from normal human tissue and stomach carcinoma tissue samples was used to select clones likely to represent sequences preferentially expressed in stomach carcinoma cells. Twenty-six recombinants were initially selected and further analysis of these clones indicated that eight (4-3D, 9-2D, 9-4G, 29-1G, 29-6F, 37-1B, 115-5A and 52-5F) contain sequences preferentially expressed in stomach carcinoma cells. We have identified the 9-4G, 29-1A, and 29-6F genes which are differentially expressed in human neoplasia.

[Immunohistochemical study of spleens in gastric cancer]

Immunohistochemical study was performed on the spleens of the stomach cancers using various monoclonal antibodies against mononuclear cells. The subjects consisted of 4 cases in stage I, 3 cases in stage II, 9 cases in stage III and 15 cases in stage IV. Five spleens of patients died of cerebrovascular disorders were used as a control. For 6 among these cancer cases, PSK was injected endoscopically into the tumor 10 days before operation. The results showed that: 1) OKT3+, OKT4+ and OKT8+ positive cells decreased in the marginal area of follicles with the progression of the stage of stomach cancer. 2) OKM1 and OKT10 positive cells increased in the marginal area of follicles and the red pulp of spleens which were in the latter stage of the stomach cancer. 3) OKIa1+ and OKB7+ positive cells decreased in the follicles in the later stage. 4) Leu7+, Leu11b+, OKT9+ and IL2 receptor+ cells apparently did not change in spite of the progression of the stage of stomach cancer. 5) OKT6+ positive cells were hardly noted in the spleen. 6) In PSK injected group, OKT4+, OKT8+ and OKB7+ cells tended to increase, while IL2 receptor+ cells and OKM1+ cells were definitely observed to increase. In conclusion, the spleen of the stomach cancer in the advanced stages exhibited the decrease of the T-cell system such as OKT3+, OKT4+ and OKT8+ cells and it is believed that the immune response was lowered through T-cell system as the stage advances. At the same time, the fact of a similar decrease in the B-cell system of OKB7+ seems to suggest a lowered state of antibody productivity. On the other hand, the increase of OKM1+ and OKT10+ cells in the advanced stage is considered to be a state of activation in the reticuloendothelial system. In the PSK injected cases, the increase of OKT4+, OKT8+ and IL2 receptor+ cells was observed. This was suggested that intratumorous injection of PSK was able to enhance the antitumor activity through the spleen by the activation of the T-cell system and reticuloendothelial system.

[Malignancy of gastric cancer according to DNA ploidy pattern and tumor markers]

Microfluorometric analysis of DNA content was performed on samples from 172 gastrectomy specimens of cancer. Histograms of DNA content were classified into three ploidy patterns; type I, II and III. Also, immunocytochemical examination for tumor markers (CEA, AFP and hCG) was performed. Type I was predominant in intramucosal carcinoma. Type III was predominant in differentiated carcinomas, in elevated type of early carcinomas and in gross type 1 and 2 of advanced carcinomas. Prognostic serosal factor exerted a greater influence on the prognosis than ploidy pattern. But in the patient without prognostic serosal factor, type III had a poorer prognosis than the other types because of vessel invasion, lymph node metastasis and liver metastasis. AFP and hCG were highly positive in type III. Furthermore type III cancer producing more than two tumor markers had an extremely poor prognosis. Analysis of ploidy pattern and tumor markers may prove to be a highly useful adjunct in the evaluation of malignancy in gastric cancer.

[Antitumor efficacy of polyamine antimetabolites and mitomycin C under polyamine-free diet]

Treatment of nude mice xenografted with human gastric cancer was carried out by polyamine antimetabolites combined with mitomycin C (MMC) and polyamine-free diet. Polyamine antimetabolites, alpha-difluoromethylornithine (DFMO) and ethylglyoxal-bis-guanylhydrazone (EGBG), were given ip in a daily dose of 1,000 mg/kg and 20 mg/kg, respectively, for 6 consecutive days. MMC 2.0 mg/kg was administered every other day. The polyamine-free diet was given from 4 days before start of the treatment through the end of the study. Although the tumor growth rate of the control group given polyamine-free diet was similar to that given normal diet, in the mice treated with EGBG, DFMO plus MMC, the antitumor effect in the polyamine-free diet group was superior to the normal diet group. In comparison with tumor growth suppression due to EGBG plus DFMO or MMC only, the polyamine-free diet group showed better result than the normal diet group to some extent. In mice treated with EGBG, DFMO plus MMC, tumor tissue spermine levels in the polyamine-free diet group were significantly depressed, compared to the normal diet group. Furthermore, marked suppression of DNA biosynthesis was observed in mice given EGBG, DFMO plus MMC together with the polyamine-free diet. These results suggest that combined treatments of polyamine antimetabolites and MMC revealed a marked enhancement of antitumor effects, under conditions of polyamine depletion, which may be responsible for the alteration in DNA structure.

Endocrine cells of gastric aberrant pancreas by PAP staining method

Histopathological classification of gastric aberrant pancreas has been done by Heinrich's criteria. However in some case it was difficult to detect incomplete Langerhans' island consisting of several endocrine cells or a single endocrine cell by usual H-E staining. To identify the distribution of incomplete Langerhans' islands and endocrine cells, we applied an enzyme antibody method utilizing PAP method for 7 cases of gastric aberrant pancreas. It became easy to identify the endocrine cells such as single cell and islet cells by using the PAP method. In all 3 cases of aberrant pancreas classified as Heinrich type II and one of 2 case of type III, Langerhans' islands or endocrine small cell groups and single cells were found. The PAP staining method was useful to determine the Heinrich's classification of the aberrant pancreas.

The presence of an aberrant type of human chorionic gonadotropin in patients with gastric or colorectal cancer

Beta subunits of human chorionic gonadotropin (beta-hCG) and human chorionic gonadotropin-like substance (hCGLS) were measured radioimmunologically in the serum and malignant tissue from patients with gastrointestinal cancer. Since serum beta-hCG and hCGLS correlate closely to those in cancer tissues, it is assumed that these two gonadotropins originate from cancer tissues. The serum hCGLS levels in 54 patients with gastrointestinal cancer were significantly higher, when compared with the findings in 19 healthy volunteers and 10 peptic ulcer patients. The frequency of high levels of serum hCGLS accounted for 71 per cent of those with operable gastric cancer, 44 per cent of those with inoperable gastric cancer, 100 per cent of those with operable colorectal cancer, and 67 per cent of those with inoperable colorectal cancer. On the contrary, serum beta-hCG levels did not differ between the volunteers and the cancer patients. In the 17 sera and 15 cancer tissues assayed, beta-hCG did not correlate to hCGLS. Moreover, the high levels of beta-hCG in cancer patients occurred in only 1/14 (7.1 per cent) of the assayed serum, and in 5/14 (35.7 per cent) of the cancer tissue. The increased production of these two hCGs may result from neoplastic transformation of an unrestrained fetal genome responsible for hCG production during gestation. It is assumed that the increased producibility of a defective hCG, i.e., an aberrant hCG such as hCGLS, is characteristic of malignant tumors.

Carbohydrate moieties of peanut agglutinin receptors isolated from human gastric cancer cells

Receptors for peanut agglutinin (PNA) were isolated from Kato III human gastric cancer cells by affinity chromatography on PNA agarose, and were labeled by the galactose oxidase-NaB3H4 method. Alkaline NaBH4 treatment of the labeled receptors released two small oligosaccharide alcohols, which were identified as Gal beta 1----3GalNAc-ol and Gal beta 1----4GlcNAc beta 1----6(Gal beta 1----3)GalNAc-ol. Higher oligosaccharides and glycopeptides of both N- and O-linked type were also detected, but they did not appear to bear PNA binding sites. The presence of oligo-N-acetyllactosamine units in the N-linked type sugars was indicated by endo-beta-galactosidase digestion.

An autopsy case of primary gastric choriocarcinoma

An autopsy case of primary gastric choriocarcinoma in a 55-year-old male is presented. The tumor was diagnosed as choriocarcinoma of the stomach from a histological examination of biopsy specimens. The level of human chorionic gonadotropin (HCG) was significantly increased in the serum and urine. A histological examination of autopsy specimens showed the tumor of the stomach to be a pure choriocarcinoma composed of syncytiotrophoblasts and cytotrophoblasts with a mixture of eosinophilic necrotic tissues, but with no elements of adenocarcinoma. The tumor showed metastases and/or invasions to the liver, lungs, pancreas, omentum, pleura, peritoneum and lymph nodes. Positive immuno-histochemical staining for the beta-subunit of HCG (HCG-beta) in the gastric tumor was demonstrated in the form of granular diffuse deposits in the cytoplasm of trophoblasts and predominated in syncytiotrophoblasts over transitional cells. Under electron microscopic observation, positive immunostaining for HCG-beta was observed in the perinuclear space, cisternae of the rough endoplasmic reticulum (RER) and secretory vesicles of syncytiotrophoblasts and transitional cells.

Gastric submucosal tumours of neurogenic origin with neuroaxonal and Schwann cell elements

Twelve cases of gastric submucosal tumours, originally diagnosed as leiomyoma and leiomyosarcoma, were investigated by staining with the neurogenic markers S-100 and neuron specific enolase (NSE). Three cases were, in addition, studied by electron microscopy. The tumours stained negatively for desmin, indicating that they were not of smooth muscle origin. All stained positively for S-100 and NSE. The ultrastructural features in the cases examined by electron microscopy were reminiscent of autonomic nerve structures normally present in the gastric wall. These included fine cytoplasmic processes of Schwann cells, wrapped with complete or incomplete basement membranes, and structures analogous to post-ganglionic neuroaxonal components. These tumours appear to represent a distinct type of gastric neoplasm originating from autonomic nerve elements in the stomach wall. They are different from previously described schwannomas or neurofibromas. In some of the tumours, identifiably neural elements are relatively a minor component, and the majority of the tumour cells are of undetermined origin. It is suggested that these cells may be poorly differentiated, lacking their antigenic determinants specific to neural differentiation.

Contradictory antitumor efficacies produced by the combination of DNA attacking drugs and polyamine antimetabolites

The antitumor effects of two polyamine antimetabolites, alpha-difluoromethylornithine (DFMO) and methylglyoxal-bis-guanylhydrazone (MGBG), when combined with cis-diamminedichlroplatinum (CDDP) or mitomycin C (MMC), were studied using human gastric cancer cells xenotransplanted into nude mice. DFMO 1000 mg/kg and MGBG 50 mg/kg were given intraperitoneally for 6 successive days, while CDDP 3 mg/kg or MMC 2 mg/kg was given every second day. Although DFMO and MGBG plus MMC did suppress the tumor growth, the combination with CDDP led to no suppression, and rapid growth occurred after the cessation of therapy. The inhibition of tumoral DNA biosynthesis and a decline in polyamine levels, were also not observed. The polyamine antimetabolites when used with CDDP did not produce the desired antitumor efficacy, even though the platinum concentration in the tumor tissue was high. On the contrary, however, DFMO and MGBG when combined with MMC did suppress tumor growth, inhibited DNA biosynthesis, and tissue polyamine levels were low. These results suggest that though CDDP and MMC belong to a similar category of DNA attacking, bifunctional alkylating agents, the findings of these two drugs are contradictory. Here, the mechanism of action no doubt plays a contributory role.

[Immunohistochemical study of ras p21 expression in human gastric cancers and benign lesions]

Expression of ras p21 in human gastric cancers, benign lesions (i.e. dysplasia, intestinal metaplasia and hyperplastic polyps) and normal tissues was immunohistochemically evaluated by the avidin-biotin complex (ABC) immunoperoxidase method with anti-ras p21 monoclonal antibody(rp-28). Positive p21-immunoreactivity was shown in 23(77%) of 30 gastric cancers, in 13(48%) of 27 benign lesions and in 10(22%) of 46 normal mucosa. Among them, strong staining was demonstrated only in 11(37%) of 30 gastric cancers, but not in benign lesions and normal tissues. Cases showing more than 20% positive cell ratio were observed in 22(73%) of gastric cancers, in 11(41%) of benign lesions and 6(13%) of normal mucosa. Furthermore, there was clear difference in intracellular distribution of ras p21 between in gastric cancers and in benign lesions or normal tissues. Plasma membrane and cytoplasm of malignant cells showed positive immunoreactivity in some gastric cancers. On the other hand, ras p21 was observed in cytoplasm of positive cells in benign tissues. The ABC method with this antibody could be useful for clinical differential diagnosis between gastric cancers and benign lesions by investigating three factors: staining intensity, positive cell ratio and intracellular distribution.

Solitary polypoid hamartoma of the oxyntic mucosa of the stomach

A solitary pedunculated polyp of the oxyntic mucosa removed from a 66-year-old patient with atrophic gastritis and achlorhydria exhibited distinctive histological features consisting of submucosal, mostly oxyntic-type glands with a smooth muscular framework. Histochemical and immunohistochemical studies demonstrated that the glands were composed of well differentiated chief, parietal, and endocrine cells. Moreover, less frequent glands of the antro-pyloric type were also seen. The lesion was regarded as a previously unrecognized variety of gastric hamartoma.

Nuclear DNA recordings in gastric carcinoids. A cytofluorometric study on single tumour cells

Cytofluorometric nuclear DNA analyses were performed on single tumour cells from eight argyrophilic gastric carcinoids. Three tumours displayed grossly diploid DNA values, with a fraction of S-phase cells of 1-8%. Four other tumours were also mainly diploid, but showed an increased number of tetraploid cells, and one tumour was aneuploid with a stem-cell line of triploid cells. These and previous results indicate that gastric carcinoids are relatively heterogenous with respect to their morphology, nuclear DNA profiles and biological behaviour, in contrast to most intestinal "classical" carcinoids. Furthermore, the results are in accordance with the suggestion that gastric carcinoids may represent a highly differentiated variety within a spectrum of neuroendocrine neoplasia analogous to the corresponding variety observed in the bronchus (carcinoid-small cell, undifferentiated carcinoma).

Intramucosal cysts in gastric mucosa adjacent to carcinoma and peptic ulcer: a histochemical study

Histochemical characteristics and the distribution of gastric intramucosal cysts were studied in 50 cancerous and 51 benign gastrectomy specimens. The frequency of such cysts was significantly higher in stomachs with carcinoma (70%) than in stomachs with peptic ulcer (43%) (P less than 0.01). Intramucosal cysts were classified into gastric type, small intestinal type, colonic type and non-mucous type. There were significant differences in the constituent ratios of the four types of cyst between gastric carcinoma and gastric ulcer (P less than 0.01), as well as between intestinal type and diffuse type cancer (P less than 0.001). The present results reveal a close relationship between intramucosal cysts and gastric carcinoma. Cysts of small intestinal, colonic and non-mucous types were associated with intestinal type cancer while cysts of gastric type were related to diffuse type cancer of the stomach.

Synthesis and secretion of an hEGF-like immunoreactive factor by human gastric cancer cells (MKN-45)

A large amount of an immunoreactive factor was detected in the medium conditioned by human gastric cancer cells, strain MKN-45, by our enzyme immunoassay system for human epidermal growth factor (hEGF) based on hEGF isolated from urine. However, the dose-response curve of the immunoreactive factor (designated as MKN-45 EGF) was not parallel with the standard curve of hEGF. The molecular weight of MKN-45 EGF was slightly larger than that of hEGF and was estimated to be 7,000-8,000 by gel filtration on Sephadex G-50. On isoelectric focusing analysis, MKN-45 EGF gave a major peak at pH 5.0 and a minor one at pH 4.3. These results demonstrate that MKN-45 cells synthesize and secrete into the culture medium a polypeptide immunologically related to hEGF.

Morphometry and cytophotometric assessment of DNA in smooth-muscle tumors (leiomyomas and leiomyosarcomas) of the gastrointestinal tract

The difficulties in predicting the biologic behavior of gastrointestinal (GI) smooth-muscle tumors (leiomyomas and leiomyosarcomas) based on the usual criteria of malignancy are discussed. In order to evaluate the prognostic importance of the nuclear DNA content and nuclear dimensions, measurements were performed on Feulgen-stained sections of GI smooth-muscle tumors from 66 patients. The best discrimination between benign and malignant tumors was obtained by using DNA index and tumor size as descriptors in a linear discriminate analysis. This method separated 79% of the benign and 97% of the malignant smooth-muscle tumors. However, as with conventional criteria for malignancy, there remained a group of tumors close to the discriminating line with an indeterminate malignant potential. In an attempt to reduce the number of such indeterminate tumors, future studies will include the use of several descriptors in a multivariate analysis system and the application of flow cytometric studies to all tumors.

Carcinoid tumour of stomach and primary hyperparathyroidism: a new association

Three cases of carcinoid tumour of the stomach associated with primary hyperparathyroidism had the clinical and pathological features of a pluriglandular syndrome. Two of the patients showed multiple small polypoid carcinoids in the non-antral stomach, in conjunction with a parathyroid adenoma in one and parathyroid hyperplasia in the other case. One of these patients was also suffering from pernicious anaemia. A third patient had a large metastasising carcinoid arising in the gastric body and a parathyroid adenoma. Immunohistochemical stains for PGP 9.5 were positive in the carcinoids of all three cases. In all cases the carcinoids showed immunoreactivity for gastrin. A positive family history of endocrine hyperplasia and neoplasia was established in one case. It is suggested that patients with gastrointestinal carcinoids and their families should be evaluated for hyperparathyroidism, and patients with hyperparathyroidism presenting with upper gastrointestinal symptoms should undergo endoscopy to rule out gastric carcinoid tumours.

Increase in S-100b protein content in thyroid carcinoma

S-100b protein was detectable in the soluble fraction of thyroid tissue. The concentration of S-100b protein in thyroid carcinoma tissue was three to five times higher than in normal thyroid tissue and thyroid adenoma. It is, however, not higher in the thyroid tissue of Graves' disease. The increase of S-100b protein concentration was not remarkable in carcinomatous tissue of the stomach and other digestive organs. The calmodulin content in the thyroid carcinoma tissue increased but the increment was low compared to that of S-100b protein. These data suggest that S-100b protein may play a significant role in cell maturation or differentiation.