Preliminary study on glucose regulated protein 78 kD and heat shock protein 20 differential expression between left-sided colon carcinoma and right-sided colon carcinoma / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To analyze the differential protein expression of left-sided colon cancer and right-sided colon cancer.</p><p><b>METHODS</b>Tissue samples of left-sided colon cancer (n=7) and right-sided colon cancer (n=7) were collected. Tissue protein was abstracted and two-dimensional gel electrophoresis (2-DE) was used to examine the gel images. Peptide mass fingerprintings (PMF) was acquired by matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and the proteins were identified by data searching with bioinformatics. Immunohistochemical SP method was used for the detection of glucose regulated protein 78 kD (GRP78) and heat shock protein 20 (HSP20) in left-sided colon cancer (n=50) and right-sided colon cancer (n=50) tissues.</p><p><b>RESULTS</b>Sixteen differentiating protein spots were identified. Compared with right-sided colon cancer, 10 proteins including GRP78 up-regulated and 6 proteins including HSP20 down-regulated in left-sided colon cancer. Immunohistochemical detection showed that in left and right sided colon cancer, the positive expression rate of GRP78 was 78% (39/50) and 56% (28/50) and the positive expression rate of HSP20 was 34% (17/50) and 72% (36/50), respectively, and the differences were statistically significant (both P<0.05). The positive rate of GRP78 was associated with tumor differentiation, infiltration layer, TNM staging, lymph node metastasis, and liver metastasis, while the positive rate of HSP20 was associated with tumor gross morphology, TNM staging, and lymph node metastasis (P<0.05).</p><p><b>CONCLUSIONS</b>There are differentially expressed proteins between left-sided colon cancer and right-sided colon cancer, especially for GRP78 and HSP20, which may be the cause leading to the biological differences between left-sided and right-sided colon cancer.</p>

Significance of aquaporin-1 and aquaporin-3 expression in colorectal carcinoma / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the significance of aquaporin-1(AQP-1) and aquaporin-3(AQP-3) in the development of colorectal carcinoma.</p><p><b>METHODS</b>The expression of AQP-1 and AQP-3 was investigated using immunohistochemical staining with Streptavidin Peroxidase in tissues from colorectal adenoma (CRA, n=25), colorectal cancer (CRC, n=50), and adjacent mucosa (CRT, n=50).</p><p><b>RESULTS</b>The positive rate of AQP-1 was 64%(32/50) in CRC, significantly higher than that in CRT (38%, 19/50) and CRA(32%, 8/25)(P<0.05). The expression of AQP-1 was associated with depth of invasion and lymph node metastasis in CRC patients(P<0.05). The positive rate of AQP-3 was 56% in CRT, 44% in CRA, and 52% in CRC. There were no significant differences (P>0.05). The expression of AQP-3 was associated with age, tumor diameter, and depth of invasion (P<0.05). No significant correlation between the expression of AQP-1 and AQP-3 in CRC was shown by Spearman correlation analysis(P>0.05).</p><p><b>CONCLUSIONS</b>AQP-1 expression is increased in CRC while the expression of AQP-3 is not. There is no correlation between the expression of AQP-1 and AQP-3 in CRC.</p>