[Expression of VEGF-C and VEGF-D in gastric carcinoma and its relationship with lymph node metastases].

OBJECTIVE: To explore the expression of vascular endothelial growth factor (VEGF) C and D in gastric cancer and its relationship with tumor angiogenesis and lymph node metastasis. METHODS: Immunohistochemistry(SABC) and real-time PCR were used to detect the expression of VEGF-C, VEGF-D protein and mRNA in 32 gastric cancer tissues and 32 normal gastric tissues. RESULTS: The positive expression rate of VEGF-C and VEGF-D in gastric cancer tissue was significantly higher than that of normal gastric tissues (P<0.01), the expression of VEGF-C and VEGF-D in the gastric cancer group and the lymph node metastasis group were significantly different (P<0.05). The expression of VEGF-C and VEGF-D in gastric carcinoma was positively correlated with lymph node metastasis (P<0.01), the expression of VEGF-C and VEGF-D in well-differentiated carcinoma, moderately differentiated carcinoma and poorly differentiated carcinoma was statistically different (P<0.05). VEGF-C and VEGF-D expressions in gastric cancer cells were not related to the patient's age, sex, and lymph node distant metastasis (P>0.05). CONCLUSION: The non-intake high expression of VEGF-C and VEGF-D in gastric cancer cells is closely related to lymph node metastasis. They serve as the important reference indicator to assess the prognosis in gastric cancer patients.

Diagnosis and treatment of 81 patients with primary gastrointestinal lymphoma.

OBJECTIVE: To analyze the status quo of the diagnosis and treatments of primary gastrointestinal lymphoma (PGIL) in order to improve it. METHODS: Eighty-one patients with PGIL were analyzed retrospectively including clinical manifestations, endoscopic features, pathological features, HP infection, treatment, and prognosis. RESULTS: The age of patients with gastric lymphoma was (52.84+/-15.33) years. The age of patients with intestinal lymphoma was (42.09+/-15.28) years. Common symptoms included abdominal pain (76.5%), gastrointestinal bleeding (55.6%), anemia (54.3%), abdominal mass (25.9%), hypoproteinemia (40.7%), bowel obstruction (11.1%), abdominal distension, vomiting, and other non-specific gastrointestinal symptoms (32.1%), weight loss (33.3%); fever (8.6%), diarrhea (7.4%), digestive tract perforation (1.2%), constipation (1.2%), and dysphagia (1.2%). Endoscopic appearances were as follows: tumor type (67.7%), ulcer type (27.7%), and diffuse type (4.6%). Clinical diagnosis rate and endoscopic biopsy confirmation rate were 30.9% and 73.8%. MALT lymphoma accounted for 61.7% of the patients. HP detection rate was 39.5% and positive rate was 37.5%. A total of 69 patients received surgeries: 3 had preoperative chemotherapy, and 34 had postoperative chemotherapy. Twelve patients had non-surgical treatment, 6 patients of whom had simple chemotherapy and HP eradication therapy, and the other 6 gave up during the treatment. There was no significant difference in the survival rate of Stage I-II patients in the surgery alone group, surgery plus chemotherapy group, and chemotherapy and HP eradication therapy group(P>0.05). The survival rate of Stage III-IV patients in the surgery alone group was lower than that in the other 2 groups (P<0.05). The 5-year, 3-year, and 1-year survival rate was 55.87%, 70.96%, and 96.39%, respectively. CONCLUSION: There are no specific clinical and endoscopic features in PGIL, so the misdiagnosis rate is high. Multi-site biopsy or repeated biopsies and immunohistochemical methods can be used to raise the pathological diagnosis rate. Chemotherapy and HP eradication are recommended.

[Experimental study of implantable engineered liver tissue using type I collagen gel as scaffold].

OBJECTIVE: To construct implantable engineered liver tissue (ELT) using type I collagen gel as scaffold. METHODS: Type I collagen was obtained from the tail of a rat. Hepatocytes were collected from a Sprague-Dawley rat, mixed with liquid type I collagen and Dulbecco's modified Eagle's medium to create hepatocyte/collagen gel construct. The construct was inoculated in a 96-well plate. 0, 3, 5, 7, 9, 11, 13, and 15 days after the inoculation the viability of hepatocytes in vitro was measured by MTT assay. Phase contrast microscopy was used to observe the morphology of the hepatocyte/collagen gel construct. Three SD rats underwent injection of the hepatocyte/collagen gel construct into the subcutaneous space. One week later the implant was taken out. The morphology was conducted by routine H.E. staining and immunohistochemical staining. The morphology and function of hepatocytes was investigated by inverted microscopy, routine H.E. staining and immunohistochemical staining. The constructs were also implanted into subcutaneous space, and the differentiation of hepatocytes and the formation of engineered liver tissue were observed by routine H.E. staining and immunohistochemical staining. RESULTS: Phase contrast microscopy showed that the hepatocytes were distributed evenly in the construct and remained round-shape throughout the in vitro culture. MTT assay demonstrated that the high viability of hepatocytes (87%) was maintained up to 7 days, and then decreased gradually. Albumin, the specific marker of hepatocytes remained positive by immunohistochemical staining after 15-day culture. One week after implantation into subcutaneous space, the implanted hepatocytes retained its hepatocyte-specific morphology, i.e. round shape, large nuclear/cytoplasm ratio as well as binuclear cells, and formed small engineered liver tissue containing blood vessels within and surrounding the tissue. CONCLUSION: A novel approach to construct implantable engineered liver tissue using collagen gel as scaffold for growth and differentiation of hepatocytes has been dev eloped. This technique is an attractive tool for the development of liver tissue engineering.