Clinico-pathologic significance of neuroendocrine cells in gastric carcer tissue

AIMS To elucidate the biological and clinicopathological signifi- cance of neuroendocrine(NE)cells in gastric carcinoma(GC). METHODS One hundred and eighty-nine cases of various histo- logical types of GC were observed using light microscopy, histochemistry,immunohistochemistry and electron microscopy. Of them 127 patients were followed up. RESULTS Chromogranin A(CgA)positive GC was demonstrat- ed in 85 cases(45.0%).The typos of NE cells in GC were probed using 9 kinds of hormone antibodies 49 cases(67.2%) contained more than one hormone.NE cells were found more often in poorly differentiated GC than in well differentiated ones(P<0. 01).Expression of some kinds of hormone Was relative to the dif- ferentiation and histological types of GC.BOM,CT(P<0.01) GAST and 5-HT(P<0.05)were more expressed in poorly differ- entiated cases than in well defferentiated ones.Nineteen cases of the matastatic foci in regional lymph nodes were found to have CgA positive cancer cells.The presence of HCG in matastatic lymph nodes was more often observed than that of other hormone (P<0.01).The survival rate of patients with NE positive GC was 38.9% and negative GC 52.7%.Five of 7 patients(71. 4%)with somatostatin positive GC still survived at follow up of 33-66 months,but 4 patients with HCG positive GC died in 12-29 months. CONCLUSIONS The NE cells occur more frequently in poorly differentiated GC.Certain hormones appear to be related to the metastasis and prognosis.

Expression of vascular endothelial growth factor and its prognostic significance in gastric carcinoma

AIMS To investigate the clinical significance of vas- cular endothelial growth factor (VEGF) expression in gastric carcinoma. METHODS The expression of VEGF in 128 gastric carcinomas was investigated by immunohistochemical staining with a polyclonal antibody against VEGF. Cor- relations between the expression of VEGF and various clinicopathologic factors and prognosis were studied. RESULTS The VEGF-rich expression rate was 64.1% in gastric carcinoma. VEGF-rich expression rate of patients with stage Ⅲ and stage Ⅳ disease was greater than that of patients with stage f disease (P <0.05). Significant differences of expression rate ex- isted with respect to growth pattern,serosal invasion and lymph node metastasis. The VEGF-rich rate was much higher in tumors with expanding growth pattern (71.8%) or serosal invasion (73.5%) than in those with infiltrative growth pattern (52.0%) or non-serosal invasion (53.3%) (P<0.025,respectively),and it was also significantly higher in patients with lymph node metastases (75.0%) than in those without such metastases (50.0%) (P<0.05). In addition,postop- erative survey of 86 patients who had been followed up for at least 5 years demonstrated that the 5-year sur- vival rate of patients with VEGF-rich tumors was signifi- cantly lower than that of patients with VEGF-poor tu- mors (P<0.05). CONCLUSIONS The expression of VEGF may be as- sociated with the invasion and metastasis and may also be a useful prognostic indicator of gastric carcinoma.

The effect pathway of retinoic acid through regulation of retinoic acid receptor α in gastric cancer cells

AIM To evaluate the role of RARα gone in mediating the growth inhibitory effect of all-trans retinoic acid(ATRA) on gastric cancer cells. METHODS The expression levels of retinoic acid receptors(PARs)in gastric cancer cells were detected by Northern blot.Transient transfection and chlorophenicol acetyl transferase(CAT)assay were used to show the transcriptional activity of β retinoic acid response element (βPARE)and AP-1 activity.Cell growth inhibition was determined by MTT assay and anchorage-independent growth assay,respectively.Stable transfection was performed by the method of Lipofectamine,and the cells were screened by G418. RESULTS ATRA could induce expression level of RARα in MGC80-3,BGC-823 and SGC-7901 cells obviously, resulting in growth inhibition of these cell lines.After sense RARα gone was transfected into MKN-45 cells that expressed rather low level of RARα and could not be induced by ATPA,the cell growth was inhibited by ATPA markedly.In contrast,when antisense RARα gone was transfected into BGC-823 cells,a little inhibitory effect by ATPA was seen,compared with the parallel BGC-823 cells.In transient transfection assay,ATPA effectively induced transcriptional activity of βRARE in MGC80-3, BGC-823,SGC-7902 and MKN/RARα cell lines,but not in MKN-45 and BGC/aRARα cell lines.Similar results were observed in measuring anti-AP-1 activity by ATPA in these cancer cell lines. CONCLUSION ATRA inhibits the growth of gastric cancer cells by up-regulating the level of RARα; RARα is the major mediator of ATRA action in gastric cancer cells;and adequate level of RARα is required for ATRA effect on gastric cancer cells.

Light and electron microscopic observation of malignant gastric leiomyoblastoma

There were only a few cases of gastric leiomy-oblastoma reported in domestic literature,while themalignant ones were even more seldom.One ofthese was diagnosed by gastroscopic biopsy with lightand electron microscopy in our department in 1988.CASE REPORTA 57-yeat old- male worker,suffered from re-current dull pain over the upper abdomen for 2