Gene expression profile of human colorectal cancer identified NKTR as a biomarker for liver metastasis.

OBJECTIVE: Liver metastasis is one of the prognostic factors of colorectal cancer (CRC). The aim of this study is to identify biomarkers that facilitate easier detection of liver metastasis. METHODS: Significance Analysis of Microarrays (SAM) and Array Data Analyzer (ADA) were applied used for the analysis of differentially differently expressed mRNAs. mRNA expression was verified by quantitative real-timer reverse transcriptiontase polymerase chain reaction (qRT-PCR). Immunohistochemistry were was used to show natural killer-tumor recognition (NKTR) expression in CRC. NKTR-knockdown CRC cells were constructed obtained by using short hairpin RNA (shRNA). Followed by CCK-8 assay, plate colony formation test, and transwell assay were used to evaluate the influence of NKTR on cell proliferation, migration, and invasion in vitro. RESULTS: SAM yielded showed 256 up-regulated and 224 down-regulated differentially differently expressed genes. Seven genes were identified by using ADA, tools and four genes were verified by using qRT-PCR. Three genes (metastasis associated lung adenocarcinoma transcript 1 (MALAT1), nuclear factor I/B (NKTR), and nuclear factor I/B (NFIB)) showed a statistically significant considerabley difference between CRC with and liver metastasis and CRC without liver metastasis. Immunohistochemical analysis showed that NKTR expression was much lower in primary CRC with liver metastasis than that in primary CRC without liver metastasis. The NKTR protein plays a role in the lytic function of natural killer (NK) cells and it has been rarely studied in the CRC. The down-regulation of NKTR by shRNA interference in CRC cells increased cell proliferation, migration, and invasion in vitro.

SPARCL1, Shp2, MSH2, E-cadherin, p53, ADCY-2 and MAPK are prognosis-related in colorectal cancer.

AIM: To investigate the expression of markers that are correlated with the prognosis of colorectal cancer (CRC) patients. METHODS: One hundred and fifty-six CRC patients were followed up for more than 3 years after radical surgery. Immunohistochemical (IHC) analysis was performed to detect the expression of 14 pathway-related markers (p53, APC, p21ras, E-cadherin, endothelin-B receptor, Shp2, ADCY-2, SPARCL1, neuroligin1, hsp27, mmp-9, MAPK, MSH2 and rho) in specimens from these patients. Bioinformatics analysis involving a Support Vector Machine (SVM) was used to determine the best prognostic model from combinations of these markers. RESULTS: Seven markers (SPARCL1, Shp2, MSH2, E-cadherin, p53, ADCY-2 and MAPK) were significantly related to the prognosis and clinical pathological features of the CRC patients (P < 0.05). Prognostic models were established through SVM from combinations of these 7 markers and proved able to differentiate patients with dissimilar survival, especially in stage II/III patients. According to the best prognostic model, the p53/SPARCL1 model, patients having high p53 and low SPARCL1 expression had about 50% lower 3-year survival than others (P < 0.001). CONCLUSION: SPARCL1, Shp2, MSH2, E-cadherin, p53, ADCY-2 and MAPK are potential prognostic markers in CRC. A p53/SPARCL1 bioinformatics model may be used as a supplement to tumor-nodes-metastasis staging.

Comparative features of colorectal and gastric cancers with microsatellite instability in Chinese patients.

OBJECTIVE: The purpose of this study was to determine the unique and universal features of microsatellite instability-high (MSI-H) colorectal cancer (CRC) and MSI-H gastric cancer (GC) in the Chinese population. METHODS: A new panel of mononucleotide MSI markers, BAT25, BAT26, NR21, NR24, and MONO-27, was used to define MSI status in 303 CRC and 288 GC subjects. Clinicopathological features of both types of MSI-H tumors were analyzed. Methylation analysis in the hMLH1 promoter region by methylation specific polymerase chain reaction (PCR) and mutation detection of hMSH2/hMLH1 genes by denaturing high-performance liquid chromatography (DHPLC) were carried out simultaneously. RESULTS: MSI-H CRCs and MSI-H GCs account for 11.9% and 8.0% of unselected sporadic CRCs and GCs, respectively. MSI-H CRCs are strongly characterized by early onset, right-side location, low differentiation, mucinous tumor, less infiltration, less lymphatic metastasis, and more often familial tumor. MSI-H GCs only showed site preference for the antrum and less lymphatic metastasis. Genetic and epigenetic analyses were positive in 6/36 MSI-H CRCs and 0/23 MSI-H GCs with pathological mutation in major mismatch repair genes, and in 7/36 MSI-H CRCs and 18/23 MSI-H GCs with methylated hMLH1 promoter (P<0.01), respectively. CONCLUSIONS: Although there are many differences in the genetic basis and clinicopathological features between MSI-H CRC and MSI-H GC, when compared with their microsatellite stable (MSS) counterparts, site preference and lymphatic metastasis are features common to both types of MSI-H tumors.

Effect of SNC19/ST14 gene overexpression on invasion of colorectal cancer cells.

AIM: To study the effect of SNC19/ST14 gene overexpression on invasion in vitro of colorectal cancer cells. METHODS: The adhesion of SNC19/ST14 gene-transfected cells to ECM was measured by MTT assay. The cell movement was evaluated by wound healing assay. Cell invasion and migration were determined by invasion assay in vitro. RESULTS: SNC19/ST14 gene overexpression could enhance invasion of colorectal cancer cells in vitro significantly and influence early cell adherence to ECM, but could not change cell movement significantly. CONCLUSION: SNC19/ST14 gene overexpression increases the local invasion of colorectal cancer cells in vitro.

[SNC19/ST14 gene transfection and expression influence the biological behavior of colorectal cancer cells].

OBJECTIVE: To study the effect of SNC19/ST14 gene transfection and expression into colorectal cancer cells on biological behavior. METHODS: The recombination vector pSecTag2a-SNC19/ST14 was constructed, and transfected into the RKO colorectal cancer cell line by liposome. The transfected cell was screened by real time PCR, Western Blot and Immunohistochemical technique. The population doubling time (T(D)) and cell cycle of the transfected cell were analyzed by MTT assay and flow cytometer. Rhodamine-labeled Phallodin was used to label the cell cytoskeletal protein-F-actin, and the F-actin distribution was observed by confocal scanning microscope. The adhesion ability of the transfected cell to extracellular matrix (ECM) was measured by MTT assay. RESULTS: The full length Open Reading Frame (ORF) of SNC19/ST14 gene was inserted into the vector pSecTag2a, and transfected into RKO cells, and expressed successfully. The changes of F-actin organization took place in transfected cell. The Adherence ability of the transfected cell to ECM was decreased, but the proliferation ability was not significantly changed except highly expressing of the SNC19/ST14, and not the cell cycle and the apoptosis. CONCLUSION: SNC19/ST14 gene was successfully expressed into the RKO cell line, and could influence on the cell cytoskeletal protein (F-actin) organization and on cell adherence ability to ECM, but could not make the cell cycle, apoptosis and proliferation ability change significantly.