Expression profile, molecular functions, and prognostic significance of miRNAs in primary colorectal cancer stem cells.

MicroRNAs (miRNAs) are known to drive the pathogenesis of colorectal cancer (CRC) via the regulation of cancer stem cells (CSCs). We studied the miRNA expression profile of primary CSCs isolated from patients with CRC (pCRCSCs). Compared to pCRCSC-derived differentiated cells, 98 differentially expressed miRNAs were identified in pCRCSCs. Target genes encoding pCRCSC-related miRNAs were identified using a combination of miRNA target databases and miRNA-mRNA regulatory networks from the same patient. The pCRCSC-related miRNA target genes were associated with pathways contributing to malignant phenotypes, including I-kappa B kinase/NF-kappa B signaling, signal transduction by p53 class mediator, Ras signaling, and cGMP-PKG signaling. The pCRCSC-related miRNA expression signature was independently associated with poor overall survival in both the training and validation cohorts. We have thus identified several pCRCSC-related miRNAs with oncogenic potential that could serve as prognostic biomarkers for CRC.

The Role of HER2 in Self-Renewal, Invasion, and Tumorigenicity of Gastric Cancer Stem Cells.

BACKGROUND: Deregulation of HER2 expression could affect the biological characteristics of gastric cancer cells and treatment option for gastric cancer patients. This research aims to investigate the impact of HER2 on biological characteristics of gastric cancer stem cells (GCSCs) and prognosis of gastric cancer patients. METHODS: HER2 knockdown in GCSCs were constructed by lentivirus transfection. Alterations of proliferation, self-renewal, invasion, migration, colony formation, and tumorigenicity of GCSCs were examined. The changes of gene expressions after HER2 interference in GCSCs were detected by gene microarray. The impact of concentration of serum HER2 and expression of HER2 in tumor tissues on survival of 213 gastric cancer patients was also analyzed. RESULTS: Down-regulation of HER2 decreased the self-renewal, colony formation, migration, invasion, proliferation, and chemotherapy resistance of GCSCs. However, the tumorigenicity of GCSCs in vivo was increased after down-regulation of HER2. The results of gene microarray showed that HER2 gene might regulate the signal transduction of mTOR, Jak-STAT, and other signal pathways and affect the biological characteristics of GCSCs. Furthermore, survival analyses indicated that patients with high concentration of HER2 in serum had a favorable overall survival. However, there was no significant correlation between expression of HER2 in tumor tissue and overall survival. CONCLUSION: Interference of HER2 in GCSCs decreased the capacity of self-renewal, proliferation, colony formation, chemotherapy resistance, invasion, and migration but might increase the tumorigenicity in vivo. Patients with high concentration of HER2 in serum seemed to have a favorable prognosis.

Peritoneal Metastatic Cancer Stem Cells of Gastric Cancer with Partial Mesenchymal-Epithelial Transition and Enhanced Invasiveness in an Intraperitoneal Transplantation Model.

OBJECTIVES: This preliminary study is aimed at enriching and isolating peritoneal metastatic cancer stem cells (pMCSCs) of gastric cancer and assessing their epithelial-mesenchymal transition (EMT) phenotype and invasiveness. METHODS: Cancer stem cells of human gastric cancer (CSC-hGC) were previously isolated and transfected with green fluorescent protein and luciferase genes to validate the mouse model of peritoneal metastasis established via transplantation. The first and second generations ([G1] and [G2], respectively) of pMCSCs were isolated from intraperitoneally transplanted CSC-hGC (pMCSC-tGC) by spherical culture. CSC and EMT-related markers and regulators in the two generations of intraperitoneally transplanted tumors were examined by immunohistochemistry, immunofluorescence staining, and quantitative PCR. Cell mobility was examined by a transwell assay. RESULTS: The nude mouse model of intraperitoneally transplanted CSC-hGC was successful in establishing sequential formation of peritoneal tumors and enrichment of pMCSCs. CD44 and CD54 were consistently expressed in the two generations of transplanted tumors. In vitro cell (migration) assays and immunocytofluorescence assays showed that in pMCSC-tGC[G2], E-cad, Survivin, and Vimentin expression was stable; α-SMA expression was decreased; and OVOL2, GRHL2, and ZEB1 expression was increased. PCR analysis indicated that in pMCSC-tGC[G2], the mRNA expression of E-cad, α-SMA, MMP9, MMP2, and Vimentin was downregulated, while that of ZEB1, OVOL2, and GRHL2 was upregulated. In vivo tumor (homing) assays and immunohistochemical assays demonstrated that in pMCSC-tGC[G2], E-cad and Snail were upregulated, while α-SMA was downregulated. The numbers of migrated and invaded pMCSC-tGC[G1] and pMCSC-tGC[G2] were significantly higher than those of CSC-hGC in migration and invasion assays. CONCLUSIONS: pMCSCs might be a specific subpopulation that can be sequentially enriched by intraperitoneal transplantation. pMCSCs exhibited a tendency towards partial mesenchymal-epithelial transition, enhancing their invasiveness during homing and the formation of peritoneal tumors. However, these preliminary findings require validation in further experiments.

High ANKZF1 expression is associated with poor overall survival and recurrence-free survival in colon cancer.

Aim: To investigate the association and prognostic value of ANKZF1 gene for survival in colorectal cancer, the mechanism of ANKZF1 level alteration and correlated signaling pathways ANKZF1 is involved. Patients & methods: The Cancer Genome Atlas COREAD dataset was analyzed by bioinformatical investigation. Results: High ANKZF1 expression is associated with poor overall survival (hazard ratio [HR]: 2.094; 95% CI: 1.188-3.689; p = 0.011) and recurrence-free survival (HR: 1.762; 95% CI: 1.021-3.042; p = 0.042) in colon cancer. Bioinformatical analysis showed ANKZF1 was upregulated by amplification and exon expression. ANKZF1 was associated with angiogenesis and cancer signaling pathways. Conclusion: High ANKZF1 is an independent factor of poor survival (overall survival and recurrence-free survival) in colon cancer by taking part in angiogenesis and some cancer signaling pathways.

Targeting Myeloid-derived Suppressor Cells and Programmed Death Ligand 1 Confers Therapeutic Advantage of Ablative Hypofractionated Radiation Therapy Compared With Conventional Fractionated Radiation Therapy.

PURPOSE: Ablative hypofractionated radiation therapy (AHFRT) presents a therapeutic advantage compared with conventional fractionated radiation therapy (CFRT) for primary and oligometastatic cancers. However, the underlying mechanisms remain largely unknown. In the present study, we compared the immune alterations in response to AHFRT versus CFRT and examined the significance of immune regulations contributing to the efficacy of AHFRT. METHODS AND MATERIALS: We established subcutaneous tumors using syngeneic lung cancer and melanoma cells in both immunocompetent and immunocompromised mice and treated them with AHFRT and CFRT under the same biologically equivalent dose. RESULTS: Compared with CFRT, AHFRT significantly inhibited tumor growth in immunocompetent, but not immunocompromised, mice. On the cellular level, AHFRT reduced the recruitment of myeloid-derived suppressor cells (MDSCs) into tumors and decreased the expression of programmed death-ligand 1 (PD-L1) on those cells, which unlashed the cytotoxicity of CD8+ T cells. Through the downregulation of vascular endothelial growth factor (VEGF), AHFRT inhibited VEGF/VEGF receptor signaling, which was essential for MDSC recruitment. When combined with anti-PD-L1 antibody, AHFRT presented with greater efficacy in controlling tumor growth and improving mouse survival. By altering immune regulation, AHFRT, but not CFRT, significantly delayed the growth of secondary tumors implanted outside the irradiation field. CONCLUSIONS: Targeting MDSC recruitment and enhancing antitumor immunity are crucial for the therapeutic efficacy of AHFRT. When combined with anti-PD-L1 immunotherapy, AHFRT was more potent for cancer treatment.

A Bottleneck in Understanding Metastatic Cancer Stem Cell of Peritoneal Seeding from Gastric Cancer: A Null Result in Brief.

The capture of peritoneal metastatic cancer stem cell of human gastric cancer (pMCSC-hGC) is important to further understand the mechanism of peritoneal metastasis in gastric cancer patients. Previously, cancer stem cells (CSCs) of gastric and rectal cancers were captured and identified. However, the bottleneck of capturing pMCSC-hGC may be the scarce surgical specimen and limited volume of peritoneal metastatic lesions from gastric cancer. Only 5.2% of patients were diagnosed of unpredictive peritoneal seeding intraoperatively, while none cell sphere were successfully formed through the identical culture approach based on peritoneal metastatic nodules. The attempt to enrich and capture pMCSC of transplanted gastric cancer (pMCSC-tGC) in immunodeficiency mice model through intraperitoneal injection of CSC-hGC may be a considerable and feasible alteration.

Forced co-expression of IL-21 and IL-7 in whole-cell cancer vaccines promotes antitumor immunity.

Genetic modification of whole-cell cancer vaccines to augment their efficacies has a history of over two and a half decades. Various genes and gene combinations, targeting different aspects of immune responses have been tested in pursuit of potent adjuvant effects. Here we show that co-expression of two cytokine members of the common cytokine receptor γ-chain family, IL-21 and IL-7, in whole-cell cancer vaccines boosts antitumor immunity in a CD4(+) and CD8(+) T cell-dependent fashion. It also generates effective immune memory. The vaccine-elicited short-term effects positively correlated with enhanced infiltration of CD4(+) and CD8(+) effector T cells, and the long-term effects positively correlated with enhanced infiltration of effector memory T cells, especially CD8(+) effector memory T cells. Preliminary data suggested that the vaccine exhibited good safety profile in murine models. Taken together, the combination of IL-21 and IL-7 possesses potent adjuvant efficacy in whole-cell vaccines. This finding warrants future development of IL-21 and IL-7 co-expressing whole-cell cancer vaccines and their relevant combinatorial regimens.

Development-associated immunophenotypes reveal the heterogeneous and individualized early responses of adult B-acute lymphoblastic leukemia.

B cell acute lymphoblastic leukemia (B-ALL) exhibits phenotypes reminiscent of normal stages of B-cell development. As demonstrated by flow cytometry, the immunophenotypes are able to determine the stages of B cell development. Multicolor flow cytometry (MFC) is more accurate at identifying cell populations. In this study, 9-color panels, including CD10, CD19, CD20, CD22, CD34, CD79a, CD179a, and IgM, which are sequentially expressed during B cell development, were designed to detect the leukemia cell subpopulations in adult B-ALL patients. In 23 patients at diagnosis, 192 heterogeneous subpopulations of leukemia cells were detected. Compared with their counterparts at diagnosis and after the 1st course of induction therapy, the responses of the subpopulations were also heterogeneous. In the CD10 population, the residual B cell subpopulations in the BCR/ABL patients were obviously reduced compared to those in the BCR/ABL patients. New subpopulations were detected in 22 of 23 patients and were primarily located in the CD34CD10 populations. Subpopulations of clonal evolution were heterogeneous after induction therapy. Our results suggest that the subpopulations in B-ALL patients should be dynamically monitored by development-associated immunophenotyping before, during, and after induction therapy and to predict the prognosis of the disease.

Clinical significance of putative markers of cancer stem cells in gastric cancer: A retrospective cohort study.

Cancer stem cells (CSCs) are thought as the source of tumor maintaining and many CSCs markers have been identified. Regarding the heterogeneity in gastric cancer (GC), TNM stage is not enough to accurately predict the prognosis. The aim of this study was to investigate the clinical significance of CSCs markers (Lgr5, Oct4, CD133, EpCAM, CD54 and Sox2) and establish a new model based on these markers to accurately predict prognosis of GC. We retrospectively enrolled 377 GC tissues from January 2006 to October 2012 to perform immunohistochemistry (IHC), and 93 pairs of GC tissues and corresponding adjacent normal gastric tissues to perform quantitative PCR (qPCR) from December 2011 to October 2012. The clinicopathological and follow-up characteristics were collected. In IHC, Oct4, CD133 and EpCAM were independently related to tumor progression, while Sox2 were associated with well or moderate differentiation (all p<0.05). Cox regression showed that Oct4-EpCAM was an independently prognostic factor, indicating that double low expression of Oct4-EpCAM group had significantly better prognosis than control group (p=0.035). Regarding qPCR, CD133 was an independent prognostic factor, showing that the prognosis of patients with CD133 high expression was significantly worse than that of patients with CD133 low expression (p<0.001). The prognostic prediction accuracy of nomogram based on Oct4-EpCAM expression in IHC was significantly better than TNM stage alone (p=0.003). Low expressions of Oct4-EpCAM in IHC and CD133 in qPCR were favorable prognostic factors in GC. The nomogram based on Oct4-EpCAM was valuable in prognostic prediction of GC patients.

Associations between serum CA724 and HER2 overexpression among stage II-III resectable gastric cancer patients: an observational study.

OBJECTIVES: Associations between serum tumor biomarkers and human epidermal growth factor receptor 2 (HER2) overexpression among locally advanced gastric cancer patients were yet to be determined and therefore warranted investigation. RESULTS: A total of 318 patients were analyzed. The odds ratios of CA724 were 4.79 (95% CI 1.55-14.79) and 6.29 (1.40-28.19) in comparing the HER2 (2+/3+) and HER2 (3+) with the negative group, respectively (p < 0.05). A combination of the four biomarkers yielded slightly but not significantly greater areas under the curve (AUC = 0.83; 0.71-0.94) than that of serum CA724 alone (0.80; 0.68-0.91); however, an index generated from the combination had better diagnostic performance with 85.7% sensitivity, 80.4% specificity and 97.8% negative predictive value to predict the strong overexpression of HER2 (3+). CA199, CEA or CA125 alone was not associated with HER2 overexpression. Leave-one-out cross-validation found a consistent association between serum CA724 and HER2 (2+/3+) overexpression. METHODS: Patients undergoing radical gastrectomy from 8/2012 to 12/2013 and with pathological stage II-III gastric cancer were retrospectively analyzed. HER2 expression of the surgical samples was estimated using immunohistochemistry; serum CA724, CA199, CEA and CA125 were preoperatively tested. Internal validation was performed using the leave-one-out approach. CONCLUSIONS: Serum CA724 is significantly associated with the overexpression of HER2 among locally advanced gastric cancer patients. The combination of CA724, CA199, CEA and CA125 is better than serum CA724 alone in predicting HER2 overexpression. External validation and further investigation of the biological mechanisms of these associations are required.

The p70S6K Specific Inhibitor PF-4708671 Impedes Non-Small Cell Lung Cancer Growth.

BACKGROUND: As a serine/threonine protein kinase, p70S6K plays an important role in tumor cells. Evidence has revealed overexpression of p70S6K and phosphorylated p70S6K (p-p70S6K) in various tumor tissues, with these proteins identified as independent prognostic markers in non-small cell lung cancer (NSCLC). In this study, we explored the role of the p70S6K specific inhibitor PF-4708671 in NSCLC. METHODS: Three NSCLC cell lines (A549, SK-MES-1, and NCI-H460) were treated with PF-4708671 at five different concentrations, including 0.1µM, 0.3µM, 1µM, 3µM and 10µM, and protein levels were determined by Western-blot. Then, PF-4708671's effects were assessed both in vitro (cell proliferation, apoptosis, cell cycle distribution, and invasion) and in vivo. RESULTS: The expression levels of p-p70S6K and the downstream effector S6 were significantly reduced by PF-4708671. Diametrically opposite, the downstream protein levels of BAD, Caspase3 and ERK had increased after treatment with PF-4708671. In addition, PF-4708671 drastically inhibited cell proliferation and invasion ability in A549, SK-MES-1 and NCI-H460 cells in vitro, causing cell cycle arrest in G0-G1 phase. Limited effects of PF-4708671 were observed on apoptosis in the three NSCLC cell lines assessed. Importantly, PF-4708671 could inhibit tumorigenesis in nude mice in vivo. CONCLUSION: These findings demonstrated that the p70S6K specific inhibitor PF-4708671 has inhibitory effects on NSCLC tumorigenesis in vitro and in vivo. Therefore, P70S6K should be considered a new potential therapeutic target, and PF-470867 may be used as targeted drug for cancer treatment.

Severe Hypoglycemia Caused by Recurrent Sarcomatoid Carcinoma in the Pelvic Cavity: A Case Report.

Nonislet cell tumor hypoglycemia (NICTH) is a paraneoplastic syndrome characterized by persistent, severe hypoglycemia in different tumor types of mesochymal or epithelial origin; however, NICTH is infrequently induced by sarcomatoid carcinoma (SC). Despite some sarcomatoid and epithelioid characteristics in few cases of malignancies from epithelium, NICTH induced by recurrent SC in pelvic cavity in this report is extremely rare.We report a case in which NICTH caused by recurrence and pulmonary metastases from SC in the pelvic cavity, and the computed tomography scan revealed multiple pelvic masses and multiple large masses in the pulmonary fields. During the treatment of intestinal obstruction, the patient presented paroxysmal loss of consciousness and sweating. Her glucose even reached 1.22 mmol/L while the serum glycosylated hemoglobin was normal and previous history of diabetes or use of oral hypoglycemic agents and insulin denied.The laboratory examination showed that the low level of insulin, C-peptide, and growth hormone levels in the course of hypoglycemic episodes suggesting to the diagnosis of hypoglycemia induced by nonislet cell tumor, and the decreased levels of insulin-like growth factor (IGF)-I and IGFBP3 and the high expression of big IGF-II in the serum further confirmed the diagnosis of NICTH. Because of the widely pelvic recurrence and pulmonary metastases were unresected, the patient was discharged from the hospital after 2 weeks treatment with dexamethasone and glucose and unfortunately died 1 week later.NICTH caused by SC in the pelvic cavity is extremely rare case in clinical. The aim of this report was to present the importance to examine big IGF-II expression in patient's serum in order to reach the diagnosis of NICTH in cases of intractable cancer-associated hypoglycemia.

SNAILs promote G1 phase in selected cancer cells.

Cells can acquire a stem-like cell phenotype through epithelial-mesenchymal transition (EMT). However, it is not known which of the stem-like cancer cells are generated by these phenotype transitions. We studied the EMT-inducing roles of SNAILs (the key inducers for the onset of EMT) in selected cancer cells (lung cancer cell line with relatively stable genome), in order to provide more implications for the investigation of EMT-related phenotype transitions in cancer. However, SNAILs fail to induce completed EMT. In addition, we proved that Snail accelerates the early G1 phase whereas Slug accelerates the late G1 phase. Blocking G1 phase is one of the basic conditions for the onset of EMT-related phenotype transitions (e.g., metastasis, acquiring stemness). The discovery of this unexpected phenomenon (promoting G1 phase) typically reveals the heterogeneity of cancer cells. The onset of EMT-related phenotype transitions in cancer needs not only the induction and activation of SNAILs, but also some particular heredity alterations (genetic or epigenetic alterations, which cause heterogeneity). The new connection between heredity alteration (heterogeneity) and phenotype transition suggests a novel treatment strategy, the heredity alteration-directed specific target therapy. Further investigations need to be conducted to study the relevant heredity alterations.

Overexpression of PROM1 (CD133) confers poor prognosis in non-small cell lung cancer.

The surface marker PROM1 is considered one of the most important marker of tumor-initiating cells, and its high expression is believed to be an adverse prognostic factor in gliomas, medulloblastoma and in other malignancies. The aims of our research were to explore the expression profile of the PROM1 in non-small cell lung cancer (NSCLC) and to assess its possible role as a prognostic factor. The protein expression profiles were determined via immunohistochemical staining assay. The clinical prognostic values of protein expression were investigated with univariate and multivariate survival analysis. The quantitative variable PROM1 expression was dichotomized according to the best cutoff value obtained by the receiver operating characteristics (ROC) analysis. The protein level of PROM1 of NSCLC was higher compared with normal tissues, and the survival analysis demonstrated the positive membrane expression and combination of membrane/cytoplasm groups of PROM1 had worse prognosis than those negative expression groups. Also, multivariate Cox regression analysis showed membrane expression of PROM1 and lymph node invasion were the independent prognostic factors. The expression of PROM1 was significantly higher than normal tissue, and high levels of PROM1 membrane expression and combination of membrane/cytoplasm expression were associated with adverse prognosis.

Immunohistochemical HER2 expression not associated with clinicopathological characteristics of stage I-III gastric cancer patients.

BACKGROUND/AIMS: The aim of this study was to investigate the association of human epidermal growth factor receptor 2 (HER2) expression with clinicopathological characteristics of resectable gastric cancer patients. METHODOLOGY: A total of 394 stage I-III surgical gastric cancer patients who were detected of immunohistochemical (IHC) HER2 expression postoperatively were included in this retrospective study. Association of IHC HER2 over-expression (3+) rate with clinicopathological characteristics was tested by univariate and multivariate analyses. RESULTS: IHC HER2 over-expression rate was 5.1% (95% CI 3.1%-7.7%). By univariate analyses, none of the clinicopathological characteristics was associated with the IHC HER2 over-expression compared to negative expression (0/1+) (p>0.05), with the exception of a higher rate (12.2%) of IHC HER2 (3+) in moderate differentiation subset (p=0.02). However, the multivariate analyses didn't selected any characteristic as an independent risk factor of IHC HER2 over-expression or the combination of IHC HER2 (2/3+). CONCLUSIONS: IHC HER2 over-expression rate is relatively low among stage I-III gastric cancer patients, and might be generally not associated with clinicopathological characteristics.

Identification of immunophenotypic subtypes with different prognoses in extranodal natural killer/T-cell lymphoma, nasal type.

To analyze the differentiation characteristics of extranodal natural killer/T-cell lymphoma, nasal type, one nude mouse model, cell lines SNK6 and SNT8, and 16 fresh human samples were analyzed by flow cytometry immunophenotyping and immunohistochemistry staining; and 115 archived cases were used for phenotypic detection and prognostic analysis. We found that CD25 was expressed by most tumor cells in all samples, and CD56(+)CD25(+) cells were the predominant population in the mouse model, the 2 cell lines, and 10 of the 16 fresh tumor samples; in the other 6 fresh tumor samples, the predominant cell population was of the CD16(+)CD25(+) phenotype, and only a minor population showed the CD56(+)CD25(+) phenotype. The phenotype detected by immunohistochemistry staining generally was consistent with the phenotype found by flow cytometry immunophenotyping. According to the expression of CD56 and CD16, 115 cases could be classified into 3 phenotypic subtypes: CD56(-)CD16(-), CD56(+)CD16(-), and CD56(dim/-)CD16(+). Patients with tumors of the CD56(dim/-)CD16(+) phenotype had a poorer prognosis than patients with tumors of the other phenotypes. Differentiation of extranodal natural killer/T-cell lymphoma, nasal type apparently resembles the normal natural killer cell developmental pattern, and these tumors can be classified into 3 phenotypic subtypes of different aggressiveness. Expression of CD56(dim/-)CD16(+) implies a poorer prognosis.

The prognostic significance of peroxisome proliferator-activated receptor ß expression in the vascular endothelial cells of colorectal cancer.

OBJECTIVE: Currently, little is known regarding the role of peroxisome proliferator-activated receptor-ß (PPAR ß) in the vascular endothelial cells (VECs) of colorectal cancers (CRCs). The aim of this study was to investigate the relationship of PPAR ß expression in the VECs of CRCs in terms of the prognosis and clinicopathological features of CRC patients. DESIGN: The expression and localization of PPAR ß in the primary cancers and the matched normal mucosal samples of 141 Swedish CRC patients were analyzed in terms of its correlation with clinicopathological features and the expression of angiogenesis-related genes. This study also included 92 Chinese CRC patients. RESULTS: PPAR ß was predominantly localized in the cytoplasm and was significantly downregulated in the VECs of CRC compared to that of the normal mucosa. The low expression levels of PPAR ß in the VECs of CRC were statistically correlated with enhanced differentiation, early staging and favorable overall survival and were associated with the increased expression of VEGF and D2-40. The patients exhibiting elevated expression of PPAR ß in CRC cells but reduced expression in VECs exhibited more favorable survival compared with the other patients, whereas the patients with reduced expression of PPAR ß in CRC cells but increased expression in VECs exhibited less favorable prognosis. CONCLUSIONS: PPAR ß might play a tumor suppressor role in CRC cells in contrast to a tumor promoter role in the VECs of CRCs.

[Zebra fish cell movements during gastrulation].

During zebrafish gastrulation, large cellular rearrangements create the formation of the three germ layers, ectoderm, mesoderm, and endoderm. This process includes three types of conserved morphogenetic movement: epiboly, involution, and convergent extension. Specially, the anterior movement of prechordal plate progenitors is essential for the location and differentiation of mesendoderm progenitors, and the pechordal plate progenitors'coherent migration is thought to be a good model to study the mechanism of cell movement in vivo. Gastrulation migration is known to be controlled by many signaling pathways such as Wnt/planar cell polarity signaling; however, the underlying molecular mechanism for cellular behavior remains unknown. At present, it is generally agree that cell adhesion and cytoskeletal rearrangement are critical factors during zebrafish gastrulation cell migration. In addition, the role of extraembryonic tissue (yolk syncytial layer) during gastrulation is concerned increasingly. Here, we described the essential factors for controlling cellular behaviors and highlighted the major issues and questions that require further investigation during zebra fish gastrular cell migration in order to provide a complete map containing all the factors for regulating gastrulation cell migration and their interactions on a cellular level.

[Lumen morphogenesis and molecular mechanisms in tubular organs during zebrafish embryonic development].

A network tubular system is an important structure in the body and organ of metazoa. The lumen of tube is fundamental units in the structure, which serve to transport material, divide the organ into different functional compartments and separate the organ from the environment. The defects of lumen formation will lead to abnormalities of the organ morphogenesis and disorder of the function. Zebrafish (Danio rerio)is an important model for development research. Meanwhile easy observation of tubular organ, the relevant mutants, and transgene linages make zebrafish to become an excellent model to study the formation of lumen in the tubular organs, including the blood vessels, neural tube, gut, exocrine pancreas, and pronephric duct, which undergo the typical morphogenesis of lumen that is involved in the organs' development. The process of lumen formation is mainly consisted of induction of extracellular signals, polarization of epithelial cell, directional transportation in the polar cells, the aggregation and transportation of fluid in the lumen, and the reconstruction of cytoskeleton in polar cells and controlled by the precise and complicated molecular networks during embryonic development. This review will summarize our current knowledge on lumen morphogenesis in four kinds of typical tubular organs during zebrafish embryonic development and the related molecular mechanisms as well as to supply helpful reference to the future studies.

Prognostic value of cancer stem cell marker CD133 expression in gastric cancer: a systematic review.

OBJECTIVE: To investigate the correlation between CD133-positive gastric cancer and clinicopathological features and its impact on survival. METHODS: A search in the Medline and Chinese CNKI (up to 1 Dec 2011) was performed using the following keywords gastric cancer, CD133, AC133, prominin-1 etc. Electronic searches were supplemented by hand searching reference lists, abstracts and proceedings from meetings. Outcomes included overall survival and various clinicopathological features. RESULTS: A total of 773 gastric cancer patients from 7 studies were included. The median rate of CD133 expression by immunohistochemistry (IHC) was 44.8% (15.2%-57.4%) from 5 studies, and that by reverse transcription polymerase chain reaction (RT-PCR) was 91.3% (66.7%-100%) from 4 studies. The accumulative 5-year overall survival rates of CD133-positive and CD133-negative patients were 21.4% and 55.7%, respectively. Meta-analysis showed that CD133-positive patients had a significant worse 5-year overall survival compared to the negative ones (OR = 0.20, 95% CI 0.14-0.29, P<0.00001). With respect to clinicopathological features, CD133 overexpression by IHC method was closely correlated with tumor size, N stage, lymphatic/vascular infiltration, as well as TNM stage. CONCLUSION: CD133-positive gastric cancer patients had worse prognosis, and was associated with common clinicopathological poor prognostic factors.