Screening for specific biomarkers in serum of patients with rheumatoid arthritis using proteomic fingerprint techniques

AIM: To detect the serum protein biomarkers and establish a diagnostic model for rheumatoid arthritis (RA) adopting matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) combined with weak cationic exchange (WCX) magnetic beads, and to study the clinical significance of the model in early diagnosis of RA. METHODS: The serum samples from 60 patients with RA, 35 patients with osteoarthritis (OA) and 36 healthy controls were prepared with WCX magnetic beads, and then analyzed on PBSⅡ-C mass spectrometer reader. The protein spectra of the serum samples were normalized by Ciphergen ProteinChip software. The peak labeling was performed by Biomarker Wizard software. The specific protein biomarkers were screened by Biomarker Pattern software to construct a diagnostic model for RA. RESULTS: Totally 33 discriminative mass-to-charge (m/z) ratio were identified to be related with RA (P<0.05). Among these, the m/z peaks at 15 715.5D, 7 771.4D, 8 959.4D, 8 469.8D and 8 710.8D were used to construct a diagnostic model in a training set. In a test set, the sensitivity and specificity of the model were 86.7%and 90.0%, respectively. CONCLUSION: The potential protein biomarkers for RA are discovered in serum by MALDI-TOF-MS combined with WCX magnetic beads. The model of multiple biomarkers provides a powerful and reliable diagnostic method for RA diagnosis with high sensitivity and specificity.     

Diagnosis of colorectal cancer by WCX magnetic bead-based serum proteomic fingerprinting

AIM: To screen the potential protein biomarkers in serum for the diagnosis of colorectal cancer (CRC) by the technique of proteomic fingerprint.METHODS: Proteomic fingerprint combining magnetic beads with MALDI-TOF-MS was used to profile and compare the serum proteins from 98 patients with CRC and 80 healthy blood donors. Proteomic patterns associated with CRC were identified by Biomarker Wizard Software. The model of biomarkers was constructed and evaluated using the Biomarker Patterns Software.RESULTS: A total 68 discriminating m/z peaks were identified to be related with CRC (P<0.01). The model of biomarkers based on the 4 biomarkers (2 870.7, 3 084.0, 9 180.5 and 13 748.8) was constructed by Biomarker Patterns Software. Using this model, excellent separation between the CRC and the controls was generated. The sensitivity of the model was 92.85% (91/98) and the specificity was 91.25% (73/80). Blind test data indicated a sensitivity of 86.95% (40/46) and a specificity of 85.00% (34/40).CONCLUSION: The biomarkers for CRC can be discovered in serum by MALDI-TOF-MS combining the use of magnetic beads. The pattern of combined markers provides a powerful and reliable method for diagnosis of CRC with high sensitivity and specificity.     

Profiling serum low molecular weight proteins in patients with chronic severe hepatitis

AIM:To profile the serum low molecular weight proteins in patients with chronic severe hepatitis with proteinchip technique. METHODS:28 cases of chronic severe hepatitis and 22 healthy controls were enrolled in the study. Serum samples were analyzed with the surface enhanced laser desorption ionization-time of flight-mass spectrometry (SELDI-TOF MS) to obtain a quantitative proteomic fingerprints with molecular masses ranging from 1 kD to 10 kD. The discriminating peaks of two groups were identified. Principal component analysis was then used as the classification method for modeling the discrimination between chronic severe hepatitis patients and healthy controls. Serum was subjected to centrifugal ultrafiltration, and the unfiltered serum and the ultrafiltrates were compared using SELDI-TOF MS. RESULTS:Compared the proteomic fingerprints of severe hepatitis serum to control serum, 39 discriminating peaks were identified (P<1×10-6). Application of principal component analysis to SELDI-TOF MS data distinguished control samples from severe hepatitis samples clearly. Compared with the unfiltered serum, the SELDI-TOF MS spectrum of the filtered serum showed very few peaks with molecular masses ranging from 1 kD to 10 kD. CONCLUSION:Differentially expressed low molecular weight proteins are observed in the serum of chronic severe hepatitis patients. On the basis of the relevant literature, the biological significance of the present study is discussed.     

Differential analysis of serum proteomics in Crohn's disease treated with infliximab

AIM: To identify the serum proteins that might serve as biomarkers for predicting mucosal healing (MH) in the patients with Crohn's disease (CD) treated with infliximab (IFX). METHODS: We collected serum samples before treatment (0 week, group A) and 14 weeks after treatment (group B) from 7 CD patients with IFX treatment who had achieved MH, as well as the serum samples from 7 CD patients who had not achieved MH (0 week, group C; 14 weeks, group D). Two-dimensional fluorescence difference gel electrophoresis was applied to analyze and compare the results of serum profiles between groups A and B, C and D, A and C, B and D. Matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry and bioinformatics tools were utilized to preliminarily identify and figure out the differentially expressed proteins. RESULTS: (1) In total, there were 44 differentially expressed spots, 36, 3, 10 and 31 differentially expressed spots were detected while comparing A with B, C with D, A with C and B with D, respectively. (2) Among those spots, 17, 2, 2 and 15 proteins were identified, respectively. In total, there were 19 differentially expressed proteins, including apolipoprotein E, apolipoprotein A-I, complement factor H, and so on. (3) Protein functional association networks were carried out based on STRING database. CONCLUSION: The serum protein profiles obviously change after IFX treatment in MH CD patients, and the serum protein profiles of MH patients are different from that of non-MH patients after IFX treatment. The 19 proteins we identified may serve as potential biomarkers for predicting MH in CD patients with IFX treatment.     

Effect of 7-hydroxyisoflavone on HCT116 cells proliferation by Id1

AIM:To investigated the effect of 7-hydroxyisoflavone (7-HIF) on the proliferation, apoptosis and stem-like cell feature of colorectal cancer cells. METHODS:The effect of 7-HIF on the proliferation of HCT116 cells was detected by WST-1 assay and colony formation assay. The effects of 7-HIF on the cell cycle distribution and apoptosis in the HCT116 cells were analyzed by flow cytometry. The expression of cell-cycle related proteins and the stemness related proteins was determined by Western blot. RESULTS:After treated with 7-HIF (200 μmol/L), the viability of HCT116 cells was inhibited, and the size and number of the colony were decreased as compared with control group (P<0.05). The G₀/G₁ phase of the cell cycle was increased. The proportion of S phase was decreased and the cells were mainly arrested in G₀/G₁ phase. The apoptotic rate of HCT116 cells was 21.4%, which was significantly higher than that in the control group (1.1%). The results of Western blot revealed that the expression of inhibitor of differentiation 1(Id1) was significantly decreased (P<0.05). The expression of cell cycle markers cyclin D1 and cyclin E, the proliferative markers survivin and PCNA, and stem cell markers CD133, ALCAM and EpCAM were all down-regulated by 7-HIF treatment (P<0.05). CONCLUSION:7-HIF inhibits the proliferation and induces the apoptosis of colorectal cancer cells, and inhibits the stem-like cell feature, which may be related to Id1 inhibition.     

Identification of specific serum biomarkers in gastric adenocarcinoma patients

AIM: To screen the possible serum biomarkers for the diagnosis of gastric adenocarcinoma. METHODS: The surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF-MS) was used to screen the serum samples from 109 cases of gastric adenocarcinoma and 106 control subjects (60 healthy subjects, 30 patients with chronic superficial gastritis and 16 cases of chronic atrophic gastritis). The differentially-expressed protein peaks were selected and isolated with high-performance liquid chromatography (HPLC), and processed with enzyme before liquid chromatography-mass spectrometry tandem mass spectrometry (LC-MS/MS) analysis. The data mining was performed with software Xcalibur program component Bioworks 3.2. RESULTS: Three differentially-expressed protein peaks were selected as potential serum biomarkers of gastric adenocarcinoma patients.The m/z peak at 5 906.5 showed the increase (8.53±4.33 in cancer group, and 0.88±0.31 in control group). The m/z peaks at 6 635.7 and 8 716.3 showed the decrease (6.54±2.44 and 0.93 ± 0.29, respectively, in cancer group and 17.56±4.43 and 2.16±0.98, respectively, in control group, P<0.01). The 3 m/z peaks were identified as fibrinogen α-chain, apolipoprotein A-II and apolipoprotein CI,respectively. The combined use of the 3 biomarkers distinguished the samples in the cancer patients out of the controls at a sensitivity of 93.85% (61/65) and a specificity of 94.34% (50/53). CONCLUSION: The fibrinogen α-chain, apolipoprotein A-II and apolipoprotein CI identified as potential markers for gastric adenocarcinoma show diagnostic values in clinical application.     

Analysis of serum biomarkers in human knee osteoarthritis

AIM: To analyze the proteomic components of the sera from knee osteoarthritis patients and normal people, and to search proteins that might serve as serum biomarkers for osteoarthritis diagnosis, treatment or pathogenesis. METHODS: Two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) was applied to analyze the sera obtained from the patients with knee osteoarthritis (n=4) and normal controls (n=4). The differentially expressed proteins were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Western blotting analysis was applied to confirm the results. RESULTS: Comparative proteomic data of serum from the patients with osteoarthritis was successfully obtained. Eight differentially expressed protein spots were observed. Five up-regulated and 3 down-regulated proteins were identified. Western blot analysis confirmed that α₂-macroglobulin was increased. CONCLUSION: There are significant differences between serum proteins obtained from the patients with knee osteoarthritis and normal controls. α₂-Macroglobulin might be utilized as potential biomarkers for the diagnosis and treatment of osteoarthritis.     

Expression and clinical significance of chemokine receptor CXCR6 in primary colorectal cancer

AIM: To investigate the expression of chemokine receptor CXCR6 in primary colorectal cancer and determine the association between CXCR6 expression and synchronous liver metastasis/prognosis. METHODS: The colorectal cancer tissues from 143 patients were collected from August 2004 to December 2008 in the First Affiliated Hospital, Sun Yat-sen University. Twenty-night cases of the adjacent normal colorectal tissues were enrolled as controls. The expression of CXCR6 was detected by immunohistochemistry and the mean intergrated absorbance ( mIA ) was calculated by Image-Pro Plus 6.0 software. The relationship between CXCR6 expression and synchronous liver metastasis/prognosis was analyzed. RESULTS: The CXCR6 staining was mainly positive in colorectal cancer tissues but not in adjacent normal colorectal tissues. The mIA of CXCR6 in colorectal cancer was 1.54±0.04 (range: 0.41~2.84), and was 1.63±0.05 and 1.41±0.08 (P<0.05) in the cases with (n=83) or without (n=60) synchronous liver metastasis, respectively. According to the mean mIA of CXCR6 (1.54), the cases was divided into high CXCR6 group (mIA≥1.54) and low CXCR6 group ( mIA <1.54). The overall survival rate in high CXCR6 group was significantly lower than that in low CXCR6 group (P<0.05). In multivariate Cox regression models, age (P<0.05), lymph node metastasis (P<0.05) and synchronous liver metastasis (P<0.01) but not CXCR6 were identified as independent risk factors for poor outcome. In subgroup analysis, high CXCR6 expression was associated with poorer survival in the patients with stage I~III colorectal cancer (P<0.01) but not those with synchronous liver metastasis (P>0.05).CONCLUSION: CXCR6 in primary colorectal cancer tissues is associated with liver metastasis. It may become a potential target for the treatment of colorectal cancer liver metastasis.     

Expression of phosphorylated MEK2 (Thr394) in colorectal cancer and its clinical implication

AIM:To analyze the phosphorylation of Thr394 residue of mitogen extracellular kinase 2 (MEK2) protein in human colorectal tissues and its clinical significance. METHODS:Formalin-fixed, paraffin-embedded human colorectal tissue specimens were immunostained with the antibody against p-MEK2 (Thr394). The expression levels of p-MEK2 in normal mucosa (n=24), adenoma (n=24) and adenocarcinoma (n=96) of colorectum were compared. Another group of colorectal adenocarcinoma samples (n=417) was used to analyze the expression of p-MEK2 (Thr394) and its relationship with clinicopathological parameters and overall survival. RESULTS:The expression level of p-MEK2 (Thr394) in normal mucosa was 100%, in colorectal adenomas was 66.7% and in colorectal adenocarcinoma was 198%, showing the tendency of decrement and statistically significant differences. No significant correlation between the expression level of p-MEK2 (Thr394) and the clinicopathological parameters including sex, age, body mass index, differentiation degree, T stage, N stage, TNM stage, hepatic metastasis and mutation of K-ras was observed. Moreover, Kaplan-Meier analysis showed that the expression level of p-MEK2 (Thr394) and the prognosis of colorectal cancer had no significant correlation. CONCLUSION: Reduction of p-MEK2 (Thr394) expression occurs during colorectal tumorigenesis. The phosphorylation of Thr394 residue in MEK2 may play an important role in the development of colorectal cancer.     

Expression and significance of T-cell immunoglobulin and ITIM domain in colorectal cancer

AIM: To study the expression and clinical significance of T-cell immunoglobulin and ITIM domain (TIGIT) in colorectal cancer. METHODS: The patients with colorectal cancer (n=80) from January 2016 to June 2018 were selected. The expression of TIGIT and CD155 in the colorectal cancer tissues and adjacent normal tissues were detected by immunohistochemical staining method. The expression of TIGIT and CD155 was also determined by Western blot and ELISA. RESULTS: The positive expression rates of TIGIT and CD155 were 78.8% (63/80) and 83.8% (67/80) in the colorectal cancer tissues, significantly higher than that in the paracancerous tissues of 8.8% (7/80) and 18.8% (15/80), respectively (P<0.05). There was a positive correlation between TIGIT and CD155 expression (r=0.867, P<0.01). The expression levels of TIGIT and CD155 were increased as the stage evolved. The positive rates of TIGIT and CD155 in the colorectal cancer tissues were correlated with the degree of differentiation, pathological stage and lymph node metastasis (P<0.05). CONCLUSION: TIGIT and CD155 are correlated with the occurrence and development of colorectal cancer, and can be used as one of the prognostic indicators of colorectal cancer.     

Identification of serum differential proteins in colorectal adenoma and early malignantly transformed adenoma by proteomics

AIM: To investigate the associated proteins and sensitive biomarkers for early diagnosis of colorectal adenocarcinoma by comparing the results of differential proteomic analysis between colorectal adenoma and early malignantly transformed adenoma. METHODS: Two-dimensional gel electrophoresis was used to define patterns of protein expressions of colorectal adenoma and early malignantly transformed adenoma. Proteins expressed differentially among groups were detected, cut out and analyzed by MALDI-TOF/TOF mass spectrometry. RESULTS: Two-dimensional protein maps of colorectal adenoma and early malignantly transformed adenoma were analyzed with gel-analysis software, an average of 1 672 spots in adenoma, 1 732 in early malignantly transformed adenoma were observed. 28 spots of a 1.5-fold change were found, including 15 proteins down-regulated and 13 up-regulated in early malignantly transformed adenoma, in which 23 proteins were identified by mass spectrometry, the rate of identification was 82.14%. 13 differential proteins were attained, 8 were up-regulated and 5 were down-regulated, which was classified to 6 categories, including protease inhibitor, complement, immunoglobulin, keratoproteins, signal transduction protein and function-unknown proteins. CONCLUSION: The changes of serum proteins in early malignantly transformed adenoma from adenoma can be identified by proteomic technology. Proteins detected in the study may provide new biomarkers correlated with biological behavior of colorectal adenocarcinoma.     

Proteomic analysis of colon cancer

AIM: To investigate the cancer associated proteins and sensitive biomarkers in colon cancer. METHODS: Two-dimensional gel electrophoresis was used to define patterns of protein expression in cancer and matched morphologically normal colonic mucosa from 8 patients. Proteins that showed differential expression of a 2-fold change were cut and analyzed by MALDI-TOF mass spectrometry. RESULTS: Two-dimensional protein maps of cancer and matched normal tissue were gained successfully. Gel-analysis software identified an average of 3289 spots in cancer while 3066 in matched normal tissue and statistical filtering yielded 31 spots of a 2-fold change, 18 of which were identified by using mass spectrometry, including keratin 8, S100A6, protein disulfide isomerase, etc. Functional analysis revealed that these proteins were associated with cancer cellular oncogenesis, proliferation, differentiation and metastasis. CONCLUSION: Proteomic analysis can identify the proteins with variance of colon cancer versus normal colonic tissue as well as providing probable new biomarkers correlated with biological behavior of colon cancer.     

Expression of STC1 in colorectal cancer and its significance in tumor microenvironment

AIM:To explore the expression of stanniocalcin 1 (STC1) in colorectal cancer tissues and to analyze its relationship with prognosis, further to investigate the correlation between STC1 and tumor microenvironment. METHODS:The data of the STC1 mRNA expression were accessed by the UALCAN database (http://ualcan.path.uab.edu/index.html) and Oncomine database (https://www.oncomine.org). RT-qPCR and Western blot were used to detect the expression of STC1 in the clinical samples. OncoLnc (http://www.oncolnc.org/) analytical tool was adopted to evaluate the correlation of STC1 level and the prognosis of colorectal cancer. CoCl₂ was used to establish the hypoxia status and lipopolysaccharide (LPS) was utilized to establish inflammatory condition in the colorectal cancer HT-29 cells, respectively, and then STC1 expression was examined by RT-qPCR and Western blot. RESULTS:STC1 was over-expressed in the colorectal cancer tissues, and its high expression was positively correlated with poor prognosis of the colorectal cancer patients (P<0.01). In colorectal cancer HT-29 cells, treatment of CoCl₂ up-regulated the expression of STC1. Under the condition of inflammation by stimulating with LPS, the expression of STC1 was significantly increased. In the colorectal cancer, STC1 level was positively correlated with hypoxia-inducible factor-1α or inflammatory molecules expression, and the levels of tumor-infiltrating immune cells in colorectal cancer tissue. CONCLUSION:STC1 is over-expressed in the colorectal tumor tissue, and the high level of STC1 is an important prognosis indicator for colorectal cancer. Furthermore, STC1 is closely correlated with tumor microenvironment, especially with the tumor hypoxia and tumor immune regulation of colorectal cancer.     

Circulating miRNA-141 as a non-invasive biomarker for prostate cancer detection and prognosis

AIM:To analyze circulating miR-141 in the serum as a non-invasive biomarker in the patients with prostate cancer (PCa) and benign prostate hyperplasia (BPH), and healthy individuals. METHODS:A total of 75 patients with PCa, 52 with BPH and 40 healthy individuals were enrolled into this study. Total RNA was isolated from the serum samples and the circulating levels of miR-141 were determined using quantitative real-time polymerase chain reaction. RESULTS:The serum levels of miR-141 were significantly higher in the patients with PCa compared to the patients with BPH and the healthy controls (P<0.01). The level of miR-141 in PCa group obviously differed from that in BPH group and healthy control group with high diagnosis performance, with areas under the curve of 0.785 and 0.801, respectively. No statistically significant difference of the serum miR-141 levels between the patients with BPH and healthy individuals was observed (P>0.05). The serum miR-141 level was also found to be related to Gleason score, clinical stage and bone metastasis status of the patients with PCa (P<0.05), and the patients with higher Gleason scores had higher serum miR-141 levels. No relationship was detected between miRNA-141 level and the patient’s age, biochemistry recurrence and serum prostate-specific antigen level (P>0.05 for all comparisons). CONCLUSION: Circulating miR-141 could serve as a non-invasive biomarker for prostate cancer diagnosis, staging and prognosis prediction.     

Effects of glutamine and recombinant human growth hormone on intestinal mucosal barrier and proliferating cell nuclear antigen in postoperative portal hypertension patients

AIM:To investigate morphologic and functional changes of small intestinal mucosa and proliferating cell nuclear antigen in postoperative portal hypertension patients with single or combined administration of Gln and rhGH.METHODS:Twenty-nine portal hypertension patients with surgical treatment were prospectively randomized to four groups as follows: ① Gln group (n=6);② rhGH group (n=8);③ Gln+rhGH group (n=7) and ④ control group (n=8).A standard solution for TPN was given three days after operation for a week.The concentration ratio of urinary lactulose and mannitol (L/M),the villus height and crypt depth and PCNA index of small intestinal mucosa were compared.RESULTS:A week after TPN postoperation,the increased ratios of L/M in Gln+rhGH group were less than those in control group (P<0.05).The villus height and crypt depth increased in Gln+rhGH group compared with preoperation (P<0.05) or control group (P<0.05).PCNA index increased in Gln+rhGH group compared with preoperation (P<0.05) or other three groups (P<0.05).The villus height of control group decreased (P<0.05),whereas the crypt depth had no significant difference (P＞0.05).CONCLUSION:This study suggest that Gln together with rhGH reduce the intestinal permeability and protect the mucosa integrality in postoperative portal hypertension patients,but not in single treatment.     

Screening and identification of specific serum biomarkers of Parkinson disease

AIM：To screen the possible serum biomarkers of Parkinson’s disease. METHODS：The surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF-MS) was used to screen the serum samples from 44 cases of Parkinson’s disease and 60 control subjects. The differentially expressed protein peaks were selected and isolated with high-performance liquid chromatography (HPLC), and processed with enzyme before analysis by liquid chromatography-mass spectrometry tandem mass spectrometry (LC-MS/MS). The data mining was performed by Xcalibur program component BioWorks 3.2. RESULTS：Three differentially expressed protein peaks were selected as potential serum biomarkers from the patients of Parkinson’s disease: the protein at 8 937 m/z peak showed significant increase (27.47±16.58 in Parkinson’s disease group, and only 5.01±3.47 in control group), and the proteins at 6 636 and 8 697 m/z peaks showed significant decreases (5.43±2.66 and 20.22±9.57, respectively, in Parkinson’s disease group, and 18.85±7.56 and 51.13±26.22, respectively, in control group). The proteins at 6 636, 8 697 and 8 937 m/z peaks were identified as apolipoprotein C-I, apolipoprotein C-III and complement 3a,respectively. Combined use of these 3 biomarkers effectively distinguished the subjects between Parkinsons disease group and control group. The detection rate of the patients with Parkinsons disease was 90.0% (27/30), and the detection rate of the healthy sibkects was 92.5% (37/40). CONCLUSION：The apolipoprotein C-I, apolipoprotein C-III and complement component 3a identified as potential markers of Parkinson’s disease have diagnostic value in clinical application.     

Mutations of K-ras oncogene in primary colorectal tumors,related liver metastases and portal vein blood of patients with colorectal cancer

AIM: To evaluate the concordance of K-ras oncogene mutations in primary colorectal tumors, liver metastases and portal vein blood of the patients with colorectal cancer, and to find out the relationship between mutated K-ras oncogene and liver metastases in colorectal cancer.METHODS: Fifty-nine patients with colorectal cancer were screened for the mutations of K-ras oncogene in the tissue samples of primary tumors, portal vein blood and liver metastases (only 15 cases of the 59 patients) by real-time fluorescence quantitative PCR and DNA sequencing. The results were also analyzed with the clinical data of the patients.RESULTS: Point mutations of K-ras were found in the primary tumors in 20 (33.9%) of the 59 patients with colorectal cancer, and 18 (30.5%) of the 59 patients in their portal vein blood. K-ras mutations in 8 (53.3%) of 15 liver metastases were also detected. No significant difference among the rates of K-ras mutation in primary tumor tissues, portal vein blood and related liver metastases was observed (P>0.05). Eighteen cases with mutated K-ras gene in portal vein blood showed the mutations in primary tumor tissues. The patients without mutated K-ras gene in primary tumor tissue also showed negative mutation of K-ras in the portal vein blood. The mutated K-ras gene in both liver metastase and portal vein blood were detected in 8 of the 15 cases with liver metastases, and no mutated K-ras gene was detected in the others with liver metastases. The main types of K-ras mutations found in primary tumors, liver metastases (5 simultaneous, 2 metachronous) and portal vein blood were GGT to GAT and GGT to GTT at codon 12. A K-ras mutation at codon 13 (GGC to GAC) was found in one case with metachronous liver metastases. The rate of concordance of K-ras status between primary tumors and portal vein blood was 96.6%. Detection of K-ras mutations in liver metastases was accordant with that in portal vein blood, but the type of K-ras mutation was partially discordant.CONCLUSION: The K-ras mutations in primary tumors, liver metastases and portal vein blood of patients with colorectal cancer are concordant, and mutated K-ras detected in both cancer tissue and portal vein blood may indicate liver micrometastases from colorectal cancer.     

Long noncoding RNA MALAT1 regulates Rac1b expression and is associated with colorectal cancer metastasis

AIM: To investigate the role of MALAT1 in colorectal cancer metastasis.METHODS: The mRNA expression levels of MALAT1 and Rac1b in the tumor and adjacent normal tissues were examined by real-time PCR. MALAT1 was knocked down by siRNA in colorectal cancer cell lines. The expression of Rac1b and the epithelial-mesenchymal transition markers was examined by Western blot. Cell proliferation was determined by EdU analysis. The effects of MALAT1 on the cell migration and invasion were examined by Transwell assay. RESULTS: The expression of MALAT1 was down-regulated in colorectal cancer. Down-regulation of MALAT1 induced Rac1b overexpression, which in turn increased the expression levels of E-cadherin and β-catenin. Furthermore, down-regulation of MALAT1 promoted the cell proliferation, invasion and migration. CONCLUSION: MALAT1 is associated with metastasis of colorectal cancer through regulating the expression of Rac1b and the downstream factors.     

Expression of Tpl-2 in colorectal carcinogenesis

AIM: To analyze the relationship between Tpl-2 (tumor progression locus 2)expression and clinicopathological parameters of colorectal carcinoma by investigating the expression of Tpl-2 in adjacent normal mucosa, colorectal adenomas and colorectal carcinoma. METHODS: Tpl-2 expression in normal mucosa, adenoma and carcinoma was examined and compared in a set of tissue microarrays by immunohistochemistry. The potential relationship between Tpl-2 expression and clinicopathological features was analyzed. RESULTS: The expression of Tpl-2 in carcinoma was significantly increased compared to the adenoma and normal mucosa (P<0.01). No significant difference was detected between the adenoma and normal mucosa (P>0.05). Meanwhile, the correlation between Tpl-2 expression and lymph node metastasis (N stage) and TNM stage (P<0.05) was observed. However, the correlation between the Tpl-2 expression and clinicopathological features of colorectal cancer including sex, age, body mass index (BMI), tumor size, histological differentiation, invasive depth (T stage),distant metastasis(M stage) and K-ras mutation (P>0.05) was not found. CONCLUSION: Tpl-2 has a relevance to the development of colorectal cancer as a promotive factor in the colorectal carcinogenesis.