The antitumor activity of recombinant antitumor antiviral protein and the associated molecular mechanism in pancreatic tumor cells.

BACKGROUND: Pancreatic cancer has poor prognosis and high mortality. Currently, the therapy of pancreatic cancer remains a challenge. In this study, we compared the antitumor activity of the recombinant antitumor antiviral protein (RAAP), an improved interferon, with gemcitabine, a classic chemotherapy agent used for pancreatic cancer treatment. METHODS: The proliferation of Bx-PC3 pancreatic cancer cells was evaluated by an MTT assay. Cell cycle arrest and apoptosis were evaluated by flow cytometry and annexin V-FITC/propidium iodide double staining, respectively. The expressions of matrix metalloproteinase (MMP)-2, MMP-9, caspase-3, caspase-8, and caspase-9 genes were evaluated by reverse transcription-polymerase chain reaction and the Western blot analysis. A xenograft pancreatic cancer model was established by inoculating Bx-PC3 cells into athymic nude mice. The antitumor activity of RAAP and gemcitabine was tested in the xenograft tumor model. RESULTS: RAAP significantly inhibited proliferation, induced cell cycle arrest, and induced apoptosis in Bx-PC3 cells in vitro and delayed tumor growth in vivo. The antitumor activity of 20 ng/mL of RAAP was a little more effective than 10 µM of gemcitabine. The antitumor activity of RAAP was associated with its role in inducing caspase-3 and caspase-8 expression as well as downregulating MMP-2 expression. CONCLUSIONS: RAAP can effectively suppress human pancreatic cancer cell growth in vitro and in vivo. The antitumor efficacy of RAAP is similar to gemcitabine.

[Modified serum-guided immunoblotting for differential proteomic study of prostate cancer].

OBJECTIVE: To search for a new method of screening for molecular targets for androgen-dependent prostate cancer. METHODS: We collected tissue samples and paired serum samples from 3 cases of androgen-dependent prostate cancer (ADPC) treated by surgical resection, and included another 3 samples of benign prostatic hyperplasia (BPH) tissue and normal human serum in the control group. The total proteins extracted were separated and transmembrane by two-dimensional gel electrophoresis, followed by hybridization with the sera of the patients with ADPC and those with hormone-independent prostate cancer (HIPC) as the primary antibodies. The differentially expressed proteins were compared by Western blot, analyzed by MALDI-TOF-MS mass spectrography, and verified by RT-PCR and Western blot following bioinformatic identification. RESULTS: This modified method exhibited a significantly better effect in displaying differentially expressed proteins, by which 12 differentially expressed protein spots were identified, including Beclin1, glutathione S-transferase P (GSTP1-1), ZBTB7, dihydrodiol dehydrogenase 2 (DDH), enolase (ENO1), glucose-dependent insulin-releasing peptide receptor (GIPR), Mn-superoxide dismutase (MnSOD), phosphoglycerate mutase 1 (PGAM1), amino-peptidyl-prolyl cistrons isomerase (PPIA), and phospholipid-PE-binding protein (PEBP). The mRNA and protein expressions of Beclin1 were significantly down-regulated in androgen-dependent prostate cancer tissues. CONCLUSION: This modified serum-guided immunoblotting technique has provided a new method for clarifying the molecular mechanisms of the occurrence and progression of HIPC, in which Beclin1-mediated autophagy may play a key role.

[Association of CK20 expression with the progression, metastasis and prognosis of breast cancer].

AIM: To analyze the expression of CK20 in human breast cancer, and to evaluate the association between its expression and tumor's progression and prognosis. METHODS: 86 cases with breast cancer, 20 cases of benign tumor tissues were examined for the expression of CK20 by immunohistochemical staining. RESULTS: The positive rate of CK20 expression in breast cancer was 80.23% (69/86), which was significantly higher than that in benign tumor tissues of breast [20.00% (4/20), P<0.01]. CK20 expression was associated with the histologic grades (P<0.05) and the pathological types (P<0.01). The expression of CK20 was observed to correlate positively with TNM stages (r=0.86, P<0.05), lymph node status (r=0.73, P<0.05) and HER-2 status (r=0.69, P<0.05), and correlate negatively with ER status (r=-0.58, P<0.05). Moreover, Kaplan Meier curves of overall survival analysis showed a significant difference between CK20 positive groups and negative group (P<0.01). CONCLUSION: The results suggest that the expression of CK20 may be associated with the progression and prognosis of breast cancer.

Prediction of prognosis in gallbladder carcinoma by CD147 and MMP-2 immunohistochemistry.

AIM: To investigate whether the presence of CD147 and MMP-2 in cancerous gallbladder tissues might help us to predict the patients' prognosis. METHODS: Tissue samples from 168 patients with gallbladder carcinomas and 37 patients with chronic cholecystitis were stained with anti-CD147 and anti-MMP-2 antibodies for immunohistochemical analysis. Then, the association of their expression with clinicopathologic characteristics and 108 patients' prognosis was analyzed. RESULTS: CD147 and MMP-2 were detected mainly in cancerous tissues, but also expressed in some chronic cholecystitis patients. Out of 168 patients with gallbladder carcinoma 121 (72.02%) and 136 (80.95%) patients showed CD147 and MMP-2 positive expression, whereas the 37 patients with chronic cholecystitis only 5 (13.51%) and 3 (8.11%) patients expressed them, respectively. Pathologic findings demonstrated that the intensity of CD147 and MMP-2 staining in cancerous tissues was associated significantly with histological types (P = 0.03), distant metastasis (P < 0.01), and Nevin stages (P = 0.02) of gallbladder carcinomas. Using a proportional hazard model, the survival rate of the patients with CD147+/MMP-2+ expression was the lowest (P < 0.01), and including information on CD147 and MMP-2 staining patterns within cancerous tissues along with clinical cancer staging may improve the accuracy of predicting patients' prognosis. CONCLUSION: The results suggest that the expression of CD147 and MMP-2 may be an important feature of gallbladder carcinomas. The detection of these two markers combined with cancerous staging may increase the ability of investigators to predict the prognosis of patients with gallbladder carcinomas.

[Expression of MMP-2, MMP-9 and collagen type IV and their relationship in colorectal carcinomas].

AIM: To investigate the expression of MMP-2, MMP-9 and collagen type IV and their relationship in colorectal carcinomas. METHODS: The expressions of collagen type IV, MMP-2 and MMP-9 was in normal and colorectal cancer tissues of 30 patients whose clinical stages were Dukes'B and C was detected with immunohistochennical staining. And the relationship among collagen type IV, MMP-2 and MMP-9 was analysed. RESULTS: The expression of collagen type IV was significantly decreased in colorectal cancer tissues. The expression of MMP-2 and MMP-9 was not detected in normal colorectal tissues but it was significantly increased in colorectal cancer tissues. There was a negative correlation between the expression of collagen type IV and MMP-9. CONCLUSION: The expression of collagen type IV in colorectal cancer tissues is lower than that in normal tissues. MMP-9 may play an important role in the degradation of collagen type IV in colorectal cancer.