KIF2C: a novel link between Wnt/β-catenin and mTORC1 signaling in the pathogenesis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and is the fourth-leading cause of cancer-related deaths worldwide. HCC is refractory to many standard cancer treatments and the prognosis is often poor, highlighting a pressing need to identify biomarkers of aggressiveness and potential targets for future treatments. Kinesin family member 2C (KIF2C) is reported to be highly expressed in several human tumors. Nevertheless, the molecular mechanisms underlying the role of KIF2C in tumor development and progression have not been investigated. In this study, we found that KIF2C expression was significantly upregulated in HCC, and that KIF2C up-regulation was associated with a poor prognosis. Utilizing both gain and loss of function assays, we showed that KIF2C promoted HCC cell proliferation, migration, invasion, and metastasis both in vitro and in vivo. Mechanistically, we identified TBC1D7 as a binding partner of KIF2C, and this interaction disrupts the formation of the TSC complex, resulting in the enhancement of mammalian target of rapamycin complex1 (mTORC1) signal transduction. Additionally, we found that KIF2C is a direct target of the Wnt/β-catenin pathway, and acts as a key factor in mediating the crosstalk between Wnt/β-catenin and mTORC1 signaling. Thus, the results of our study establish a link between Wnt/β-catenin and mTORC1 signaling, which highlights the potential of KIF2C as a therapeutic target for the treatment of HCC.

Expression of ALC1 in tissues of esophageal squamous cell carcinoma and its effect on ESCC cell proliferation, invasion, and migration / 中国肿瘤临床

Objective: To investigate the expression of ALC1 protein during esophageal squamous cell carcinoma (ESCC) development and progression, so as to explore its association with clinicopathological characteristics and overall survival of ESCC patients, and the effect of ALC1 overexpression on malignant biological behavior of esophageal squamous cells. Methods: Immunohistochemistry (IHC) was used to detect ALC1 protein expression in 245 primary ESCC tissues and their paired normal esophageal mucous membranes, and to determine its correlation to gender, age, tumor cell differentiation, invasion, TNM stage, lymph nodes metastasis, and overall surviv-al rate of ESCC patients. MTT assay, colony formation assay, transwell invasion, and wound healing assay were used to observe the ef-fect of ALC1 on ESCC cell proliferation, invasion, and migration. Results: The expression ratio of ALC1 in esophageal squamous cell car-cinoma was higher compared with that in their paired normal esophageal mucous membranes (41.6% vs . 21.2% , P<0.05). Upregula-tion of ALC1 was associated with ESCC invasion, TNM stage, and lymph node metastasis (P<0.05). The overall survival of ESCC patients with ALC1 overexpression was significantly lower than that in patients with downregulated ALC1 expression (P=0.002). Therefore, ALC1 may promote the proliferation, invasion, and migration of ESCC cells. Conclusions: ALC1 upregulation may play an important role in the progression and development of ESCC. Upregulation of ALC1 leads to poorer disease prognosis, and could promote the prolifera-tion, invasion, and migration of the KYSE30 ESCC cells. Therefore, ALC1 may have potential prognostic value for ESCC patients.

Role of cell adhesion molecule L1 like in the inhibition of the metastasis of esophageal squamous cell carcinoma / 中华消化杂志

Objective To investigate the role of cell adhesion molecule L1 like (CALL) in the genesis and development of esophageal squamous cell carcinoma (ESCC).Methods From July 2007 to December 2010,a total of 100 patients with ESCC who received radical resection of esophageal cancer were enrolled.The ESCC tissues and corresponding tumor-adjacent normal tissues were obtained.The expression of CALl was determined by tissue microarray technology and immunohistochemical staining.The CALL over-expressed esophageal cancer cell line was established.The effects of CALL on cell migration and invasion were detected by wound-healing assay and Transwell assay,respectively.The effects of CALL on actin microfilament was analyzed by filamentous actin (F-actin) staining.Chi square test,Fisher's exact test,multivariate analysis and t test were performed for statistical analysis.Results The positive expression rate of CALL in ESCC tissues was 56 ％ (56/100),which was lower than that of tumor-adjacent normal tissues (95％,95/100),and the difference was statistically significant (x2=41.114,P＜0.01).There were statistically significant differences in CALL expression at protein level among patients with ESCC of different differentiation degree,different pathological T stage,lymph node metastasis and different TNM stage (x2=13.702,5.317,21.453,Fisher's exact test;all P＜ 0.05).The five year disease related survival rate of ESCC patients with down-regulated expression of CALL was 0(0/49),which was lower than those with normal CALL expression (25.5％,13/51),and the difference was statistically significant (x2 =43.338,P＜0.01).The median survival time of CALL expression down-regulated group was 17 months,and that of normal expressed group was 38 months.CALL expression was an independent risk factor of disease special survival rate (hazard ratio (HR) 0.353,95％ confidence interval (CI) 0.188 to 0.666,P=0.001).The results of wound-healing assay showed that the migration ability of CALL overexpressed CALL-k30 cells was lower than that of Vec-k30 cells in control group on 24 hours after wound.The results of Transwell invasion test showed the number of migrating cells penetrating CALL k30 cells attached to the inferior surface of the membrane was 44.000±13.748,which was less than that of the Vec k30 cells (154.333±25.007),and the difference was statistically significant (t=5.136,P=0.036).The results of F-actin staining demonstrated that actin filaments of CALL-k30 cells was 234.667 ± 65.118,which was lower than that of Vec-k30 cells (597.000± 119.929),and the difference was statistically significant (t=4.707,P=0.042).Conclusions CALL lowers the migration and invasion abilities of esophageal cancer cells by inhibiting F-actin microfilaments.Its abnormal expression may play an important role in the genesis,development and prognosis of ESCC.

Type I collagen secreted by lung cancer cells promotes cancer cell growth in a three- dimensional culture system / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the role of type I collagen as an autocrine protein in promoting the growth lung cancer cells in a three-dimensional (3D) culture system.</p><p><b>METHODS</b>Immunohistochemistry and RT-PCR were used to detect the expression of type I collagen in lung cancer specimens and 5 lung cancer cell lines. The lung cancer cell lines in 3D cultures were treated with vectors harboring short hairpin RNA (shRNA) targeting type I collagen, and the cell growth suppression was evaluated using MTT assay and colony formation assay. The lung cancer cells stimulated with supernatant from lung cancer-derived fibroblasts were tested for the expression of type I collagen mRNA.</p><p><b>RESULTS</b>Type I collagen expressions were detected in both the lung cancer tissues and the cell lines. In the 3D culture system, the growth of the cancer cell lines was obviously suppressed by shRNA-mediated type I collagen knockdown evidenced by lowered cell growth rate and colony formation ability. Stimulation with fibroblast culture supernatant resulted in enhanced expressions of type I collagen in the cancer cell lines.</p><p><b>CONCLUSION</b>Autocrine of type I collagen I is required for maintaining lung cancer cell growth in 3D cultures, and its expression is regulated by fibroblasts. These findings provide new insights into the role of type I collagen I in the tumor microenvironment and point a new direction for targeted therapy of tumors.</p>

Analysis of comparative genomic hybridization and loss of heterozygosity in 43 primary gastric carcinomas / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To investigate common chromosomal changes and the LOH frequency of microsatellite loci in primary gastric cancer samples in order to locate the deleted regions in which human gastric cancer related genes might exist.</p><p><b>METHODS</b>Comparative genomic hybridization (CGH) was used to define global chromosomal aberrations in 43 primary gastric tumors. Based on the results of CGH, analysis of loss of heterozygosity (LOH) was performed in chromosome 19 in which the loss was first discovered in the gastric cancers. The PCR-based approach was used to investigate 22 loci, which are spaced at 1.1 - 10.9 cM intervals throughout chromosome 19. The amplified PCR fragments were subjected to electrophoresis in PAGE gel and analyzed with Genescan trade mark and Genotyper trade mark.</p><p><b>RESULTS</b>CGH analysis revealed gains in chromosome 3p (8/43), 8q (8/43), 20 [20 (9/43), 20p (7/43), 20q (4/43)], 12q (16/43), 13q (12/43) and losses in 19 [19 (15/43)], 7 [17 (8/43), 17p (10/43)], 16 (10/43) and 1p (11/43). Among the 43 evaluated samples, the most frequent LOH was detected at locus D19S571 (27.81%).</p><p><b>CONCLUSIONS</b>The tumorigenesis of gastric cancer includes several chromosomal changes. The aberration of chromosome 19 was the first common change founded in gastric cancer. The region near the D19S571 might harbor potential genes related to the tumorigenesis of gastric cancer.</p>

Significance of MRP1/CD9 protein expression in human hepatocellular carcinoma / 中国普通外科杂志

Objective To investigate the expression of MRP1/CD9 protein in human hepatocellular carcinoma (HCC),and its relationship to carcinoma invasion and metastasis. Methods The specimens of tissue microarray from 152 primary hepatocellular carcinomas with paracancerous liver tissue, 22 tumor emboli , 4 intrahepatic satellite metastases, 17 extrahepatic metastases ,and 5 normal livers, respectively, were constructed and used for detection of MRP1/CD9 expression by immunohistochemistry. Results Immunohistochemical analysis of tissue microarrays demonstrated MRP1/CD9 protein expression in 27.0%(41/152)of the primary HCCs. The expression of MRP1/CD9 protein was higher in HCCs without cancer thrombi than in those with cancer thrombi (40.48%vs21.82%,P10cm, P20?g/L, P=0.029). Conclusions Loss of MRP1/CD9 protein expression may be associated with invasion and metastases of hepatocellular carcinoma.

Tissue microarray in studying difference of cell proliferation and microvessel density between hepatic malignant and benign lesions / 第二军医大学学报

Objective: To study the difference of the cell proliferation activity and microvessel density (MVD) between hepatic benign and malignant lesions for further demonstrating the biological features of tumor. Methods: There were 290 specimens of hepatocellular carcinoma (HCC), 128 specimens of cirrhosis tissues and 25 specimens of hepatic benign lesions were detected for PCNA, Ki 67 and MVD by immunohistochemistry on tissue microarray, respectively.Results: The expression level of PCNA and Ki 67 in HCC were 90.2% and 43.1%, which was obviously higher than that in cirrhosis (48.5% and 3.9%, P 0.05). MVD counting in HCC pathological grade Ⅰ Ⅱ(29.9?18.6) was higher than those in gradeⅢ (22.2? 18.2) and Ⅳ(22.9?19.0, P