Zeng-Ren Zhao

Nup88 Expression in Normal Mucosa, Adenoma, Primary Adenocarcinoma and Lymph Node Metastasis in the Colorectum

Objectives: It was the aim of this study to investigate Nup88 expression in normal colorectal mucosa, adenoma, adenocarcinoma and lymph node metastasis, as well as the relationship between Nup88 expression and clinicopathological features. Methods: Nup88 expression was examined by immunohistochemistry in 84 normal mucosa samples, 32 adenomas, 181 primary adenocarcinomas, and 18 lymph node metastases from colorectal tumour patients. Results: Nup88 expression was observed in normal epithelial and tumour cells. The frequency of strong Nup88 expression was increased from normal mucosa or adenoma to primary tumour and lymph node metastasis (p < 0.0001). There was no significant difference in the expression between normal mucosa and adenoma (p = 0.41). The frequency of strong Nup88 expression was higher in ulcerated tumours (40%) than in polypoid/large fungating tumours (23%; p = 0.048). The frequency of strong Nup88 expression was significantly different among tumours with good (21%), moderate (42%) and poor differentiation (48%; p = 0.01). Nup88 expression was not related to the patients’ gender, age, tumour location, size, histological type, invasive depth, lymph node status and Dukes stage (p > 0.05). Conclusion: Our results suggest that Nup88 may play a role during the development, aggressiveness and differentiation of colorectal tumours.

Expression of MAC30 in rectal cancers with or without preoperative radiotherapy.

Objective: Meningioma-associated protein (MAC30) is overexpressed in several types of cancers, but its therapeutic implication in the patients has not been studied. We examined the relationship of MAC30 with clinicopathological and biological factors in rectal cancer patients with or without radiotherapy (RT). Methods: MAC30 was immunohistochemically examined in 75 distant and 91 adjacent normal mucosa specimens, 132 primary tumours and 39 lymph node metastases from rectal cancer patients participating in a clinical trial of preoperative RT. Results: In the RT group, MAC30 was or tended to be positively correlated with infiltrated growth pattern (p = 0.02), PRL (phosphatase of regenerating liver, p = 0.01) and Ki-67 expression (p = 0.06). MAC30 at the invasive margin of the metastasis was related to poor survival (p = 0.02) in the whole group of patients. MAC30 in primary tumours was not related to recurrence and survival in the non-RT or RT group. Conclusions:MAC30 expression in metastasis was an indicator for poor survival. After RT, MAC30 seemed to be more related to aggressive morphological and biological factors; however, we did not find direct evidence that MAC30 expression was related to the outcome of patients with or without RT.

Expression and significance of FXYD-3 protein in gastric adenocarcinoma.

Objective: FXYD-3, also known as Mat-8, is a member of the FXYD protein family. It was reported that this protein can associate with and modify the transport properties of Na, K-ATPase, and may play an important role in a variety of physiological and pathological states. This protein is up-regulated in certain types of cancers (such as breast, prostate and pancreatic cancer), but down-regulated in other types of cancers (such as colon and kidney cancer). No study has been performed in gastric cancer; therefore, the aim of this project was to investigate FXYD-3 expression and its clinicopathological significance in gastric adenocarcinoma. Patients and methods: FXYD-3 protein was examined by immunohistochemistry in normal gastric mucous (n = 29) and gastric adenocarcinoma (n = 51), obtained from surgical resection of gastric cancer patients. Results: FXYD-3 protein was present in the cytoplasm of normal gastric epithelial cells or gastric cancer cells. The rate of FXYD-3 strong expression was significantly higher in cancer (51% of 51) than in normal mucosa (10% of 29, X2=13.210, p < 0.0001). FXYD-3 expressed strongly in ulcerative/infiltrating types of cancers compared to polypoid/fungating ones (X2 = 5.765, p = 0.016). However, FXYD-3 expression was not correlated with patient’s gender, age, tumor size, lymph node status and histological grade (p > 0.05). Conclosion: Up-regulated expression of FXYD-3 protein may be involved in tumourgenesis and invasion of gastric adenocarcinoma.

Tumor-suppressing roles of miR-214 and miR-218 in breast cancer

MicroRNAs (miRNAs) are small non-coding RNAs that are key post-transcriptional regulators of gene expression. MicroRNA-214 (miR-214) and microRNA-218 (miR-218) have shown the function of tumor suppressors in various types of human cancers. However, the biological functions of miR-214 and miR-218 in breast cancer have not been elucidated completely. The present study evaluated the expression and biological function of miR-214 and miR-218 in human breast cancer. Our results revealed that the expression of miR-214 and miR-218 were significantly decreased in breast cancer tissues compared with adjacent tissues. The aberrant expression of miR-214 and miR-218 were negatively associated with Ki-67, and the miR-218 expression was positively associated with progesterone receptor (PR) in breast cancer tissues. In vitro, the cell proliferation and migration were decreased, cell apoptosis was induced, and cell cycle was also disturbed in miR-214 or miR-218 overexpressed breast cancer cells. Our results demonstrated that miR-214 and miR-218 function as tumor suppressors in breast cancer, and may become biomarkers and potential therapeutic targets in breast cancer.

Significance of mRNA and protein expression of MAC30 in progression of colorectal cancer.

Background: Meningioma-associated protein (MAC30), first described to be overexpressed in meningiomas, exhibits altered expression in certain human tumors. The aim of our study was to investigate the expression of MAC30 mRNA and its correlation with clinicopathological variables in human colorectal cancer (CRC). Methods: MAC30 mRNA expression was first examined in 55 CRCs, along with the samples from the matched distant normal and adjacent noncancerous tissue by RT-PCR, further verified in 18 CRCs by quantitative RT-PCR. MAC30 protein expression was detected by Western blot in 10 CRCs, and DNA sequencing was performed in 1 case of the paired CRC and the matched noncancerous specimen. MAC30 mRNA expression in two colon cancer cell lines, HCT-116p53–/– and HCT-116p53+/+, was detected by quantitative RT-PCR. Results: The mRNA expression of MAC30 was increased in CRC when compared with distant normal (p < 0.01) and adjacent noncancerous mucosa (p < 0.01). The mean value of MAC30 mRNA expression in the tumor located in the colon was higher than in the rectum (0.677 ± 0.419 vs. 0.412 ± 0.162, p = 0.005). As the tumor penetrated the wall of the colon/rectum, MAC30 mRNA expression notably increased in tumors with T3+T4 stage compared to tumors with T1+T2 stage (0.571 ± 0.364 vs. 0.404 ± 0.115, p = 0.014). MAC30 protein expression in CRCs was also remarkably elevated compared to the adjacent noncancerous mucosa. There was no mutation in the coding region of the MAC30 gene either in CRC or in the noncancerous mucosa. mRNA expression of p53 was notably decreased in HCT-116p53–/– compared to HCT-116p53+/+, while MAC30 did not vary greatly. Conclusion: The overexpression of MAC30 might be involved in the development and aggressiveness of CRCs, especially in the colon.

Nup88 mRNA overexpression in colorectal cancers and relationship with p53.

OBJECTIVES We measured nucleoporin 88 (Nup88) mRNA expression in primary colorectal cancers to investigate its relationship with clinicopathological features and p53. METHODS The primary cancer tissues, adjacent noncancerous tissues and the proximal and distant margins of normal mucosa were collected from 73 colorectal cancer patients during surgery. Nup88 mRNA expression was measured on these fresh specimens and on colon cell lines HCT-116^{p53 + / + } and HCT-116^{p53 - / - } by RT-PCR while p53 mRNA and β-actin as controls. Nup88 and p53 protein expression were then immunohistochemistrically examined in other 25 colorectal cancers specimens paraffin embedded and formalin fixed. RESULTS Nup88 expression was higher in primary cancer tissues than in adjacent noncancerous tissues, and in the proximal and distant margins of normal mucosa. Overexpression of Nup88 mRNA was statistically associated with TNM stage (P=0.044), lymphatic metastasis (P=0.022), and cancer location (P=0.036), while not related to gender, age of patients and histological type, infiltration depth, and differentiation of cancers. The expression of Nup88 mRNA in the HCT-116^{p53 - / - } cell line was not significantly different from expression in the HCT-116^{p53 + / +}cell line. And there was no correlation between Nup88 and p53 protein expression (r=0.632, P=0.368). CONCLUSIONS Nup88 mRNA was overexpressed in colorectal cancers and the overexpression was associated with cancer development and aggressiveness. Nup88 might be regard as essential contributor to nodal metastagenicity of colorectal cancer.

Biological effects and clinical characteristics of microRNA‑106a in human colorectal cancer

MicroRNAs serve important roles in various diseases, particularly cancer. microRNA-106a (miR-106a) exhibits abnormal expression and oncogenic activity in carcinogenesis. The clinical significance of the abnormal expression of miR-106a in colorectal cancer is poorly understood. In the present study, miR-106a expression from colorectal cancer tissues was quantified using the reverse transcription-quantitative polymerase chain reaction. The overexpression or knockdown of miR-106a was performed by transfection with microRNA mimic or inhibitor in human colorectal carcinoma HCT116 cells. The overexpression of miR-106a promoted viability and inhibited apoptosis in colorectal cancer cells. The association between miR-106a expression and clinicopathological factors was analyzed, and it was identified that miR-106a exhibited significantly increased expression in adenocarcinoma tissues compared with in mucinous carcinoma tissues, and the expression of miR-106a was identified to be associated with the depth of invasion and differentiation. The expression of miR-106a in plasma was also determined and it was identified that increased expression of miR-106a, as a characteristic of patients with colorectal cancer, may be distinguished from that of other patients by digitization of the areas under the receiver operating characteristic curves. These data suggested that miR-106a is a potential biomarker in the diagnosis of colorectal carcinoma. However, the underlying molecular mechanism of miR-106a-promoted viability and inhibition of apoptosis requires further investigation.

MANBA polymorphism was related to increased risk of colorectal cancer in Swedish but not in Chinese populations

β-mannosidase, encoded by MANBA, has been suggested to be implicated in cancers, while genetic variations in the MANBA in relation to colorectal cancer (CRC) risk has not been examined. In this study, we investigated the relationship of a polymorphic CA repeat in MANBA gene with CRC risk in 152 Swedish CRC patients and 441 Swedish controls, and 196 Chinese CRC patients and 577 Chinese controls, as well as the clinicopathologic significance of this polymorphism on CRC patients, by using capillary electrophoresis. The MANBA genotypes were related to CRC risk in the Swedish population (p=0.03), but not in the Chinese population. In the Swedish population, individuals with < 22 CAs/< 22 CAs had significantly increased risk for CRC compared with those with ≥22 CAs/≥ 22 CAs (gender-age-adjusted analysis: OR 1.93, 95% CI 1.06–3.51). There was no relationship between the polymorphism and clinicopathologic variables. These findings suggest the different susceptibilities of this polymorphism to CRC development in the two populations.