Expression and clinical significances of Beclin1, LC3 and mTOR in colorectal cancer

Autophagy is related to cancer and other diseases, and compromised autophagy could promote chromosome instability associated with carcinogenesis and tumor progression. The role of autophagy in the growth and metastasis of colorectal cancer (CRC) remains poorly understood. Beclin1 mediates autophagic initiation, and LC3 is a specific marker for autophagy. Inactivation of mTOR caused by cellular hypoxia or energy deficiency induces autophagic activity. This study aims to examine the expression and clinical significance of these proteins in CRC. Immunohistochemistry results showed that the positive expression rates of Beclin1, LC3, and mTOR in cancer tissues were 90.50%, 87.19%, and 46.28%, respectively, which were higher than those in adjacent tissues (P < 0.05). Differentiation degree and lymph node metastasis were associated with LC3 overexpression (P < 0.05) but not with Beclin1 (P > 0.05). Lymph node metastasis was also related to mTOR. Spearman analysis results showed that LC3 expression was positively correlated with Beclin1 but negatively correlated with mTOR (r = 0.593 and -0.165, respectively; P < 0.01). Beclin1 expression was also not associated with mTOR (P > 0.05). Survival analysis further indicated that LC3, mTOR, and lymph node metastasis were independent prognostic factors in CRC. Real-time PCR results and Western blot indicated that Beclin1, LC3, and mTOR expression in CRC was significantly higher than that in adjacent tissues (P < 0.01). The aberrant protein expression may be associated with the development and progression of CRC. The LC3 and mTOR genes must be simultaneously detected to evaluate progression and prognosis of CRC.     

Expression of ITGB1 predicts prognosis in colorectal cancer: a large prospective study based on tissue microarray

Background: ITGB1 is a heterodimeric cell-surface receptor involved in cell functions such as proliferation, migration, invasion and survival. The aim of this study was to assess ITGB1 expression in colorectal cancer and correlate it with clinicopathological features, as well as to evaluate its potential prognostic significance. Materials and methods: In this study, we examined the expression of ITGB1 using tissue microarrays containing analyzed specimens by immunohistochemistry. ITGB1 expression was further correlated with clinicopathological and prognostic data. The prognostic significance was assessed using Kaplan-Meier survival estimates and log-rank tests. A multivariate study with the Cox’s proportional hazard model was used to evaluate the prognostic aspects. Results: ITGB1 expression was present in 88.5% of the analyzed specimens. Significant differences in ITGB1 expression were found between normal mucosa and carcinomas (P<0.001). High ITGB1 expression was associated with poor prognosis, and it independently correlated with shortened overall survival and disease-free survival in colorectal cancer patients (P<0.001). More so, ITGB1 expression, bowel wall invasion, lymph node metastasis and distant metastasis were independent prognostic factors for overall survival. Additionally, significant differences in ITGB1 expression were observed in adenomas and tumors from patients with familial adenomatous polyposis compared to normal colon mucosa (P<0.05) Conclusion: The results of this study indicate that ITGB1 overexpression in colorectal tumors is associated with poor prognosis, as well as aggressive clinicopathological features. Therefore, ITGB1 expression could be used as potential prognostic predictor in colorectal cancer patients.     

Distinct patterns of ALDH1A1 expression predict metastasis and poor outcome of colorectal carcinoma

Purpose: Aldehyde dehydrogenase 1A1 (ALDH1A1) has been proposed as a candidate biomarker for colorectal carcinoma (CRC). However, the heterogeneity of its expression makes it difficult to predict the outcome of CRC. The aim of this study was to evaluate the diagnostic and prognostic value of this molecule in CRC. Methods and Results: In this study, we examined ALDH1A1 expression by immunohistochemistry including 406 cases of primary CRC with corresponding adjacent mucosa, with confirmation of real-time PCR and Western blotting. We found that the expression patterns of ALDH1A1 were heterogeneous in the CRC and corresponding adjacent tissues. We defined the ratio of ALDH1A1 level in adjacent mucosa to that in tumor tissues as R_A/C and found that the capabilities of tumor invasion and metastasis in the tumors with R_A/C < 1 were significantly higher than those with R_A/C ≥ 1. Follow-up data showed the worse prognoses in the CRC patients with R_A/C < 1. For understanding the underlying mechanism, the localization of β-catenin was detected in the CRC tissues with different patterns of ALDH1A1 expression from 221 patients and β-catenin was found preferentially expressed in cell nuclei of the tumors with R_A/C < 1 and ALDH1A1^high expression of HT29 cell line, indicating that nuclear translocation of β-catenin might contribute to the increased potentials of invasion and metastasis. Conclusion: Our results indicate that R_A/C is a novel biomarker to reflect the distinct expression patterns of ALDH1A1 for predicting metastasis and prognosis of CRC.     

Association between KIAA1199 overexpression and tumor invasion,TNM stage,and poor prognosis in colorectal cancer

To investigate the expression of KIAA1199 in tumor tissue and its potential value as a prognostic indicator of survival in patients with colorectal cancer (CRC). The expression of KIAA1199 mRNA in CRC was characterized using real-time PCR and 20 pairs of fresh-frozen CRC tissues and corresponding non-cancerous tissues. KIAA1199 protein expression was confirmed using immunohistochemistry on a tissue microarray chip from 202 patients with CRC. Then, we correlated KIAA1199 protein expression to CRC conventional clinicopathological features and patient’s outcome. The expression of KIAA1199 mRNA and protein were up-regulated in CRC compared to normal tissues (P = 0.015 and P < 0.001, individually). KIAA1199 protein expression was related to tumor invasion depth (P = 0.013) and lymph node metastasis (P = 0.003). Kaplan-Meier survival and Cox regression analyses revealed that high KIAA1199 expression (P < 0.001) and serum carcinoembryonic antigen (CEA) level post operation (P = 0.005) were independent factors predicting poor prognosis of patients with CRC. We present evidence that high expression of KIAA1199 is associated with tumor invasion depth, TNM stage, and poor prognosis in CRC. Our findings suggest KIAA1199 could be used as a prognostic factor and novel therapeutic target for CRC.     

Upregulated SLC1A5 promotes cell growth and survival in colorectal cancer

Glutamine metabolism is essential for tumorigenesis of colorectal cancer, cancer cells remodel their glutamine metabolic pathways to fuel rapid proliferation. SLC1A5 is an important transporter of glutamine various cancer cells. In this study, we investigated SLC1A5 protein expression in colorectal cancer and evaluated its clinical significance and functional importance. Immunohistochemical analysis was performed on tissue microarrays containing 90 pairs of cancer and adjacent normal tissues from colorectal cancer patients, we found that SLC1A5 expression increased significantly in colorectal cancer compared with normal mucosa tissues (P < 0.001). We further validated SLC1A5 overexpression in 12 pairs of fresh cancer and adjacent normal mucosa tissues from colorectal cancer patients by Western blot (P < 0.05). SLC1A5 expression levels were strongly associated with T stage of tumor (P < 0.05), and the tubular adenocarcinoma subtype (P < 0.001). Moreover, downregulation of SLC1A5 by synthetic siRNA could suppress proliferation and induce apoptosis in colorectal cancer cell lines HT29 and HCT116. In conclusion, our results provide for the first time the differential expression in human colorectal cancer and normal tissues, and a functional link between SLC1A5 expression and growth and survival of colorectal cancer, making it an attractive target in colorectal cancer treatment.     

Lemur tyrosine kinase-3 is a significant prognostic marker for patients with colorectal cancer

Lemur tyrosine kinase-3 (LMTK3) belongs to the family of serine-threonine-tyrosine kinases and the aberrant expression of LMTK3 was observed in several human malignancies. However, the association of LMTK3 with clinical outcomes in colorectal cancer patients is unclear. Thus, this present study was to evaluate the association of LMTK3 expression level with clinicopathologic factors and prognosis of patients with colorectal cancer (CRC). The expression level of LMTK3 in 69 archival paraffin-embedded colorectal tumor tissue specimens was examined by immunohistochemistry (IHC). As a result, we found that the LMTK3 expression level was significantly elevated in CRC tissues as compared with Crohn’s disease or colorectal polyp tissues (P<0.0001, P<0.0001, respectively). Positive LMTK3 signals in the colorectal cancer cells were observed in about 89.9% (62 of 69) CRC tissue specimens. Additionally, LMTK3 expression was significantly correlated with lymph node metastasis and tumor-node-metastasis (TNM) classification (P=0.003, and P=0.008, respectively), but not with sex, age, tumor location, histological differentiation, tumor size, or depth of tumor invasion (all P>0.05). Kaplan-Meier survival curves showed that the overall survival rate was significantly higher in the patients with low expression of LMTK3 when compared with those patients with high LMTK3 (P=0.010). Moreover, multivariate analysis revealed that LMTK3 expression was an independent prognostic factor for CRC patients (P=0.047). These results suggest that LMTK3 protein could serve as a prognostic marker for CRC patients.     

Lgr5 over-expression is positively related to the tumor progression and HER2 expression in stage pTNM IV colorectal cancer

Recent studies display that Leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5) appears to involve the initiation of colorectal cancer (CRC). However, its role in the progression of CRC is not clear at present. In the present study, the expression of Lgr5, HER2, VEGF, and Ki-67 was detected by immunohistochemistry in primary cancer tissue and the matched normal mucosa, metastatic lymph node and distant metastatic tissues in 42 CRC cases staged as pTNM IV. The correlation of Lgr5 over-expression with the CRC progression, survival time, and expression of HER2, VEGF, and Ki-67 was evaluated. Moreover, the Lgr5 expression at the invasive front or residual cancer cells around coagulation necrosis was compared with that at the center of CRC in 51 paraffin embedded tissues. The results revealed that Lgr5 over-expression was more frequently found in the metastatic tissues of both lymph nodes and distant area when compared with primary CRC tissue (P<0.05). Additionally, cancer cells in the invasive front and residual cancer cells around or among the coagulation necrosis presented stronger Lgr5 immunoreactivity than that at tumor center (P<0.05), and strong positive staining was often observed in tumor budding cells. While, HER2 over-expression was detected in 28.9% (IHC 3+) and 42.1% (IHC 3+/2+) of CRC patients, neither Lgr5 nor HER2 expression was significantly related to the prognosis of CRC patients, though there was a positive correlation between Lgr5 and HER2 (P<0.05) or Ki-67 expression (P<0.05). In conclusions, Lgr5 over-expression might involve the proliferation, invasion, and distant and regional metastasis of CRC cells, and has potential positive relation to HER2 expression.     

Overexpression of L1 cell adhesion molecule correlates with aggressive tumor progression of patients with breast cancer and promotes motility of breast cancer cells

Background and purpose: L1 cell adhesion molecule (L1CAM) has been observed to be aberrantly expressed and implicated in progression of several types of human cancers. However, its roles in breast cancer have not been fully elucidated. In this study, we aimed to investigate the clinical significance of L1CAM in human breast cancer and to validate whether it participates in cancer cell migration and invasion. Methods: Immunohistochemical analysis of 100 breast cancer and matched non-cancerous breast tissues was performed to detect the expression and sub-cellular localization of L1CAM protein. Its associations with clinicopathological characteristics of breast cancer patients were statistically analyzed and its phenotypic effects were also evaluated in vitro. Results: Of the 100 breast cancer patients, 89 (89.0%) were positive for L1CAM immunostaining localized in the membrane of cancer cells. The immunoreactive scores of L1CAM protein in breast cancer tissues were significantly higher than those in matched non-cancerous breast tissues (P<0.05). Chi-Square analysis showed the significant associations between L1CAM overexpression and high tumor stage (P=0.01), advanced tumor grade (P=0.03), positive lymph node metastasis (P=0.01) and tumor recurrence (P=0.01) in breast cancer patients. Moreover, we found that RNA interference-mediated knockdown of L1CAM could inhibit the migration and invasion abilities of breast cancer cells in vitro. Conclusions: Our results suggest that the overexpression of L1CAM may be related to several established markers of poor prognosis in breast cancer patients. L1CAM might be a potential therapeutic target against metastatic breast cancer.     

Increased LEF1 Expression and Decreased Notch2 Expression Are Strong Predictors of Poor Outcomes in Colorectal Cancer Patients

Background/Objective. We aimed to examine the expression of lymphoid enhancer factor 1 (LEF1) and Notch2 in colorectal cancer (CRC) and their association with clinicopathologic variables and CRC patients'' prognosis. Methods. Immunohistochemistry, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blot analysis were performed to assess the expression of LEF1 and Notch2 in 184 patients with CRC. Results. We observed a strong negative correlation between LEF1 expression and Notch2 expression (P < 0.001). Both LEF1 mRNA and protein expression increased while the Notch2 mRNA and protein expression decreased in tumor specimens compared with the matched paratumorous normal tissue (P < 0.001). An increase in LEF1 protein expression was significantly associated with lymph node metastases, distant metastasis, advanced TNM (tumor-node-metastasis) stage, and shorter overall survival. A decrease in Notch2 protein expression was associated with poorly differentiated tumors, lymph node metastases, distant metastasis, advanced TNM stage, and shorter overall survival of patients. In the multivariate Cox regression analysis, the LEF1 protein expression (P < 0.001), Notch2 protein expression (P < 0.001), TNM stage (P < 0.001), and the combination of increased LEF1 protein coexpression and decreased Notch2 protein coexpression (P < 0.001) were found to be independent prognostic indicators in CRC. Conclusion. Our results suggest that increased LEF1 coexpression and decreased Notch2 coexpression represent a risk factor for poor overall survival of CRC patients.     

Increased expression of miRNA-182 in colorectal carcinoma: an independent and tissue-specific prognostic factor

Increasing evidence has revealed that miRNAs play a pivotal role in multiple processes of carcinogenesis, and are being explored as diagnostic, prognostic and predictive biomarker. In this study, we investigated the status of miR-182 expression in colorectal carcinoma (CRC) by in situ hybridization and its underlying clinicopathologic significance for patients with CRC. We found that 79/138 (57.25%) CRCs had high-level expression of miR-182, while 17/67 (25.37%) normal mucosa tissues had high-level expression of miR-182. The expression level of miR-182 was remarkably up-regulated in CRC tissues compared with non-neoplastic normal tissues (P < 0.001). The over-expression of miR-182 in cancer parenchyma cells in CRC were strongly correlated with T-stage (P = 0.020), lymph node metastasis (P = 0.003), distant metastasis (P = 0.002), and Dukes’ stage (P = 0.005) in patients with CRC. Patients with high-level expression of miR-182 had short overall survival time than those with low-level expression of miR-182 (P < 0.001). Univariate and multivariate survival analyses further showed that miR-182 expression was a potential unfavorable prognostic factor for CRC, suggesting a potential application of miR-182 in prognosis prediction and therapeutic application in CRC.     

Clinicopathological correlation and prognostic significance of sonic hedgehog protein overexpression in human gastric cancer

Objectives: This study investigated the expression of Sonic Hedgehog (Shh) protein in gastric cancer, and correlated it with clinicopathological parameters. The prognostic significance of Shh protein was analyzed. Methods: Shh protein expression was evaluated in 113 cases of gastric cancer and 60 cases of normal gastric mucosa. The immunoreactivity was scored semi quantitatively as: 0 = absent; 1 = weak; 2 = moderate; and 3 = strong. All cases were further classified into two groups, namely non-overexpression group with score 0 or 1, and overexpression group with score 2 or 3. The overexpression of Shh protein was correlated with clinicopathological parameters. Survival analysis was then performed to determine the Shh protein prognostic significance in gastric cancer. Results: In immunohistochemistry study, nineteen (31.7%) normal gastric mucosa revealed Shh protein overexpression, while eighty-one (71.7%) gastric cancer revealed overexpression. The expression of Shh protein were significantly higher in gastric cancer tissues than in normal gastric mucosa (P < 0.001), which was statistically correlated with age (P = 0.006), tumor differentiation (P < 0.001), depth of invasion (P = 0.042), pathologic staging (P = 0.017), and nodal metastasis (P = 0.019). We found no significant difference in both overall and disease free survival rates between Shh overexpression and non-expression groups P = 0.168 and 0.071). However, Shh overexpression emerged as a significant independent prognostic factor in multivariate Cox regression analysis (hazard ratio 1.187, P = 0.041). Conclusions: Shh protein expression is upregulated and is statistically correlated with age, tumor differentiation, depth of invasion, pathologic staging, and nodal metastasis. The Shh protein overexpression is a significant independent prognostic factor in multivariate Cox regression analysis in gastric cancer.     

PIK3CA and PIK3CB expression and relationship with multidrug resistance in colorectal carcinoma

The phosphoinositide 3-kinases (PI3Ks) are a critical family of signaling enzymes that participate in many cellular processes that promote the transformation of a normal cell into a cancer cell. These processes include cancer cell proliferation, migration, and invasion. However, the correlation between PI3Ks and multidrug resistance (MDR) remains unclear. The prognostic value of PI3Ks has not been previously evaluated. Thus, this study aims to evaluate the association between PIK3CA and PIK3CB expression and the MDR gene in colorectal cancer (CRC) patients. Immunohistochemistry was employed to detect the expressions of PIK3CA, PIK3CB, MDR-1, LRP, GST-π, and Topo II in 316 CRC specimens. Patients were followed-up annually by telephone or at an outpatient clinic. Results revealed that PIK3CA and PIK3CB expression was correlated with the degree of tumor differentiation and lymph node metastasis (P < 0.05). The overexpression of MDR-1, LRP, Topo II, and GST-π was found to be 72.78%, 70.89%, 77.53%, and 76.58% of CRC, respectively. Correlation analysis showed that PIK3CA and PIK3CB expression exhibits a positive correlation with MDR-1, LRP, and GST-π with correlation coefficients of 0.288, 0.128, and 0.197, respectively (P < 0.05). Kaplan-Meier analysis revealed that the five-year survival rate of patients without lymph node metastasis, positive expression of PIK3CA and PIK3CB, and negative expression of GST-π and MDR-1 was higher than those with these characteristics. Multivariate analysis revealed that GST-π, MDR-1 expression, and lymph node metastasis could serve as independent predictive factors of overall survival. The expression of both PIK3CA and PIK3CB is increased and related to the development and progress of colorectal carcinoma and MDR. The combined detection of PIK3CA andPIK3CB is important for patients with colorectal carcinoma in prognosis and optimal therapy.     

miR-126 regulated breast cancer cell invasion by targeting ADAM9

Accumulating evidence has shown that microRNAs (miRNAs) deregulation is commonly observed in human malignancies and crucial to cancer metastasis. Herein, we demonstrated that miR-126 play a suppressor role in human breast cancer cells invasion through the direct repression of a disintegrin and metalloprotease 9 (ADAM9). MiR-126 expression was investigated in forty cases of breast cancer specimens by real-time PCR. Transwell assay was conducted to explore the effects of miR-126 on the invasion of human breast cancer cell lines. The impact of miR-126 overexpression on putative target ADAM9 was subsequently confirmed by Western blot analysis. Our results indicated that miR-126 expression was frequently down-regulated in breast cancer specimens compared with adjacent normal tissues (P<0.05). Overexpression of miR-126 significantly reduced (P<0.05) the protein levels of ADAM9, further suppressed (P<0.05) breast cancer cell invasion in vitro. Meanwhile, knockdown of ADAM9 by small interfering RNA (siRNA) also inhibited (P<0.05) breast cancer cell invasion. Thus, our study revealed that miR-126 may act as a tumor suppressor via inhibition of cell invasion by downregulating ADAM9 in breast cancer development.     

Over-expression of lncRNA DANCR is associated with advanced tumor progression and poor prognosis in patients with colorectal cancer

Despite advances made in the diagnosis and treatment of human colorectal cancer (CRC), the long-term survival for CRC remains poor. Long non-coding RNA anti-differentiation ncRNA (lncRNA DANCR) was identified to be involved in carcinogenesis of hepatocellular carcinoma. While its expression in CRC and potential role in tumor progression is still unknown. In the present study, we investigated the expression level of lncRNA DANCR as well as its association with CRC progression and prognosis. The expression of lncRNA DANCR was detected by quantitative real-time PCR (qRT-PCR) in 104 CRC specimens. The prognostic value of lncRNA DANCR was further analysis. Our results showed that lncRNA DANCR expression was increased in CRC tissues compared with that in adjacent normal tissues (P<0.05). In addition, tumors with high lncRNA DANCR expression was correlated with TNM stage, histologic grade, and lymph node metastasis (P<0.05). Kaplan-Meier analysis showed that patients with high lncRNA DANCR expression had a shorter overall survival (OS) and disease-free survival (DFS) compared with the low lncRNA DANCR expression group (P<0.05). Moreover, in a multivariate Cox model, our results showed that lncRNA DANCR expression was an independent poor prognostic factor for both OS and DFS in CRC. Our data indicated that lncRNA DANCR expression might be a novel potential biomarker for CRC prognosis.     

Overexpression of eIF3e is correlated with colon tumor development and poor prognosis

EIF3e is a component of the eukaryotic translation initiation factor 3 (eIF-3) complexes, which is an essential factor for initiation of protein synthesis in mammalian cells. Translational control plays key roles in the complex mechanism of cancer development and progression. However, the clinical significance of eIF3e in colon cancer remains to be elucidated. We analyzed the eIF3e expression in a tissue microarray (TMA), which contained 173 colon cancer tissues paired with adjacent normal mucosa and lymph node metastasis. The expression of eIF3e was significantly elevated in colon cancer tissues in comparison with those in adjacent normal mucosa (P < 0.001) and lymph node metastasis (P < 0.001). The high expression of eIF3e in colon cancer was significantly correlated with tumor size (P < 0.001), lymph node involvement (P < 0.001), distant metastasis (P < 0.001), clinical stage (P < 0.001), histopathologic classification (P < 0.001), and vessel invasion (P = 0.036). Univariate and multivariate analysis revealed that eIF3e is an independent prognosis factor for overall survival and disease-free survival in colon cancer. Down-regulation of eIF3e in vitro inhibited colon cancer cell proliferation, clonality and promoted cell apoptosis. Taken together, high eIF3e expression may contribute to tumor progression and predict poor prognosis in colon cancer.     

Correlations between expression levels of thymidylate synthase,thymidine phosphorylase and dihydropyrimidine dehydrogenase,and efficacy of 5-fluorouracil-based chemotherapy for advanced colorectal cancer

The efficacy of 5-fluorouracil (5-FU)-based chemotherapy for colorectal cancer (CRC) widely varies among patients; therefore, it is difficult to accurately predict chemotherapeutic responses. Some recent studies have found that key enzymes in the various metabolic pathways activated by 5-FU present potential predictors of treatment outcome. Of these enzymes, thymidylate synthase (TS), thymidine phosphorylase (TP), and dihydropyrimidine dehydrogenase (DPD) are known to play important roles in the efficacy of therapeutic agents. Here, we measured expression levels of TS, TP, and DPD in formalin-fixed, paraffin-embedded, CRC specimens and paracancerous tissue with normal mucosa by immunohistochemical and fluorescence real-time quantitative polymerase chain reaction techniques. We found no significant differences in TS, TP, and DPD expression levels between CRC specimens and paracancerous tissues (P > 0.05), although overall survival and the chemotherapeutic effect were relatively poor in CRC patients with relatively high expression levels of TS, TP, and DPD, as compared to those with comparatively low expression levels (P < 0.05). Therefore, TS, TP, and DPD mRNA levels appear to be suitable indicators of the efficacy of 5-FU-based chemotherapy and prognosis of CRC.