Maspin and tumor metastasis

SERPINB5 is a prognostic biomarker and promotes proliferation, metastasis and epithelial-mesenchymal transition (EMT) in lung adenocarcinoma

BACKGROUND

Serine protease inhibitors clade B serpins (SERPINBs) are the largest subclass of protease inhibitors, once thought of as a tumor suppressor gene family. However, some SERPINBs exhibit functions unrelated to the inhibition of catalytic activity.

METHODS

The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), Gene Set Cancer Analysis (GSCA), and cBioPortal databases were utilized to investigate SERPINBs expression, prognostic correlation, and genomic variation in 33 cancer types. We also conducted a comprehensive transcriptome analysis in multiple lung adenocarcinoma (LUAD) cohorts to reveal the molecular mechanism of SERPINB5 in LUAD. Then, qPCR and immunohistochemistry were used to verify the expression and prognostic value of SERPINB5 in LUAD patients. Furthermore, knockdown and overexpression of SERPINB5 in LUAD cell lines were performed to evaluate cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT).

RESULTS

The expression of SERPINB5 was upregulated and demethylated in LUAD, and its abnormally high expression was significantly correlated with poor overall survival (OS). In addition, the expression of SERPINB5 was analyzed to determine its prognostic value in LUAD and confirmed that SERPINB5 was an independent predictor of LUAD in TCGA and GEO cohorts and qPCR validation with 106 clinical samples. At last, A knockdown of SERPINB5 in LUAD cells reduced proliferation, migration, and EMT. Proliferation, migration, and invasion are promoted by the overexpression of SERPINB5.

CONCLUSION

Therefore, SERPINB5 has shown potential as a prognostic biomarker for LUAD, and it may become a potential therapeutic target for lung adenocarcinoma.

Description of a serpin toxin in Loxosceles (Brown spider) venoms: Cloning, expression in baculovirus-infected insect cells and functional characterization

Several classes of toxins are present in the venom of Brown spiders (Loxosceles genus), some of them are highly expressed and others are less expressed. In this work, we aimed to clone the sequence of a little expressed novel toxin from Loxosceles venom identified as a serine protease inhibitor (serpin), as well as to express and characterize its biochemical and biological properties. It was named LSPILT, derived from Loxoscelesserine protease inhibitor-like toxin. Multiple alignment analysis revealed high identity between LSPILT and other serpin molecules from spiders and crab. LSPILT was produced in baculovirus-infected insect cells, resulting in a 46-kDa protein fused to a His-tag. Immunological assays showed epitopes in LSPILT that resemble native venom toxins of Loxosceles spiders. The inhibitory activity of LSPILT on trypsin was found both by reverse zymography and fluorescent gelatin-degradation assay. Additionally, LSPILT inhibited the complement-dependent lysis of Trypanosoma cruzi epimastigotes, reduced thrombin-dependent clotting and suppressed B16-F10 melanoma cells migration. Results described herein prove the existence of conserved serpin-like toxins in Loxosceles venoms. The availability of a recombinant serpin enabled the determination of its biological and biochemical properties and indicates potential applications in future studies regarding the pathophysiology of the envenoming or for biotechnological purposes.

Vascular endothelial growth factor C participates in regulation of maspin in extravillous trophoblast cell migration and invasion

Mammary serine protease inhibitor (maspin ; also known as serpin family B member 5 (SERPINB5)) plays a vital role in regulating the biological functions of extravillous trophoblast (EVT) cells, but the mechanism remains unclear. Vascular endothelial growth factor (VEGF ) C is a signature angiogenic molecule expressed and secreted by first-trimester trophoblasts, and bioinformatics analyses has revealed upregulation of VEGFC in pre-eclampsia. The aim of this study was to explore whether maspin regulates EVT cells by regulating the expression of VEGFC . Reverse transcription-polymerase chain reaction and western blotting were used to investigate the effects of hypoxia on the expression of VEGFC in EVT cells. Cells were treated with recombinant (r) maspin and decitabine (to selectively inhibit DNA methyltransferases and then upregulate maspin gene expression), and the effects on VEGFC expression evaluated. In addition, the effects of rVEGFC on the biological functions of EVT cells invitro were evaluated using cell migration and invasion assays. Hypoxia increased the expression of VEGFC in EVT cells. rMaspin upregulated the expression of VEGFC in normoxic EVT cells, and downregulated the expression of VEGFC in hypoxic EVT cells at 24h. Decitabine increased VEGFC expression in normoxic EVT cells, but had no significant effect on VEGFC expression in hypoxic EVT cells. rVEGFC promoted the migration and invasion of normoxic EVT cells and inhibited the invasion of hypoxic EVT cells. These results suggest that VEGFC is involved in the regulation of maspin in EVT cell migration and invasion. However, other molecular mechanisms may be involved and require further investigation.

Potential of Protein-based Anti-metastatic Therapy with Serpins and Inter α-Trypsin Inhibitors

In this review we summarize the principles of anti-metastatic therapy with selected serpin family proteins, such as pigment epithelial-derived factor (PEDF) and maspin, as well as inter α-trypsin inhibitor (IαIs) light chains (bikunin) and heavy chains (ITIHs). Case-by-case, antimetastatic activity may be dependent or independent of the protease-inhibitory activity of the corresponding proteins. We discuss the incidence of target deregulation in different tumor entities, mechanisms of deregulation, context-dependent functional issues as well as in vitro and in vivo target validation studies with transfected tumor cells or recombinant protein as anti-metastatic agents. Finally, we comment on possible clinical evaluation of these proteins in adjuvant therapy.

Implication of vascular endothelial growth factor A and C in revealing diagnostic lymphangiogenic markers in node-positive bladder cancer

Several lymphangiogenic factors, such as vascular endothelial growth factors (VEGFs), have been found to drive the development of lymphatic metastasis in bladder cancer (BCa).

Here, we have analyzed the gene expression of lymphangiogenic factors in tissue specimens from 12 non-muscle invasive bladder cancers (NMIBC) and 11 muscle invasive bladder cancers (MIBC), considering tumor and tumor-adjacent normal bladder areas obtained from the same organs. We then compared the results observed in patients with those obtained after treating human primary bladder microvascular endothelial cells (MEC) with either direct stimulation with VEGF-A or VEGF-C or by co-culturing (trans-well assay) MEC with bladder cancer cell lines varying in VEGF-A and VEGF-C production based on tumor grade.

The genes of three markers of lymphatic endothelial commitment and development (PDPN, LYVE-1 and SLP-76) were significantly overexpressed in tissues of MIBC patients showing positive lymphovascular invasion (LVI+), lymph node metastasis (Ln+) and tumor progression. Their expression was also significantly enhanced either after direct stimulation of MEC by VEGF-A and VEGF-C or in the trans-well assay with each bladder cancer cell line.

SLP-76 showed the highest gene expression. Both VEGF-A and VEGF-C also enhanced the expression of SLP-76 protein in MEC. However, a correlation between increase of SLP-76 gene expression and the ability of MEC to migrate could only be seen after induction by VEGF-C.

The significant expression of SLP-76 in LVI+/Ln+ progressive MIBC and its overexpression in MEC after VEGF-A and VEGF-C stimulation suggest the need to develop this regulator of developmental lymphangiogenesis as a diagnostic tool in BCa.

Mammary serine protease inhibitor and CD138 immunohistochemical expression in ovarian serous and clear cell carcinomas

This study aims to investigate the immunohistochemical expression of mammary serine protease inhibitor (maspin) and CD138 in primary ovarian high-grade serous carcinomas (HGSC) as compared to low-grade serous carcinomas (LGSC) and clear cell carcinomas and investigate if the studied markers have a correlation to International Federation of Gynaecology and Obstetrics (FIGO) stage, Ki67 proliferation index, and to each other. Maspin cellular location varied significantly between studied groups with only nuclear expression seen in 46.7 % of LGSC group, mixed nuclear and cytoplasmic in 13.3, 28.6, and 20 % of LGSC, HGSC, and clear cell carcinoma, respectively, and was only cytoplasmic in 26.7, 71.4, and 80 % of LGSC, HGSC, and clear cell carcinoma, respectively. Mean maspin and CD138 counts were significantly higher in HGSC and clear cell carcinoma compared to LGSC. Both maspin and CD138 scores varied significantly between studied groups and were positively correlated with adverse prognostic factors in studied carcinomas including FIGO stage and Ki67 proliferation index. Besides, both maspin and CD138 had significant correlation to each other. These findings suggest that epithelial cytoplasmic expression of maspin and CD138 may have a significant role in tumorigenesis in ovarian high-grade serous carcinomas and clear cell carcinomas; these markers may regulate tumor cell proliferation, and their significant correlation to each other may suggest that CD138 probably induces maspin expression to protect tumor growth factors from being lysed by proteolytic enzymes.

Different maspin functions in the lung adenocarcinoma A549 and SPC-A1 cell lines

Mammary serine protease inhibitor (maspin) is a tumor suppressor gene that is silenced in the majority of cancer cells during metastatic progression by transcriptional and epigenetic mechanisms. The function of maspin in non‑small cell lung cancer cells (NSCLC) has not been clearly defined. In the present study, the expression of maspin in NSCLC cell lines, in particular, the adenocarcinoma cell lines, was heterogeneous. While the expression levels of maspin in PC‑9 and H460 cell lines were intact, the expression of maspin in the A549 and SPC‑A1 cells was hardly detected. Ectopic expression of maspin in A549 cells carrying the K‑ras gene point mutation significantly inhibited cell migration and invasion abilities, which was associated with downregulated expression of matrix metalloproteinase‑2 and integrin β1. Ectopic expression of maspin in SPC‑A1 cells harboring the wild‑type K‑ras gene predominantly affected cell growth via targeting the AKT signaling molecules. Maspin functions differently in lung adenocarcinoma cells, possibly due to the varied molecular characteristics.

Role of maspin in cancer

Maspin (mammary serine protease inhibitor), is a member of the serine protease inhibitor/non-inhibitor superfamily. Its expression is down-regulated in breast, prostate, gastric and melanoma cancers but over-expressed in pancreatic, gallbladder, colorectal, and thyroid cancers suggesting that maspin may play different activities in different cell types. However, maspin expression seems to be correlated with better prognosis in prostate, bladder, lung, gastric, colorectal, head and neck, thyroid and melanoma cancer. In breast and ovarian cancer maspin significance is associated with its subcellular localization: nucleus maspin expression correlates with a good prognosis, whilst in pancreatic cancer it predicts a poor prognosis. Since tumor metastasis requires the detachment and invasion of tumor cells through the basement membrane and stroma, a selectively increased adhesion by the presence of maspin may contribute to the inhibition of tumor metastasis. Furthermore the different position of maspin inside the cell or its epigenetic modifications may explain the different behavior of the expression of maspin between tumors. The expression of maspin might be useful as a prognostic and possibly predictive factor for patients with particular types of cancer and data can guide physicians in selecting therapy. Its expression in circulating tumor cells especially in breast cancer, could be also useful in clinical practice along with other factors, such as age, comorbidities, blood examinations in order to select the best therapy to be carried out. Focusing on the malignancies in which maspin showed a positive prognostic value, therapeutic approaches studied so far aimed to re-activate a dormant tumor suppressor gene by designed transcription factors, to hit the system that inhibits the expression of maspin, to identify natural substances that can determine the activation and the expression of maspin or possible “molecules binds” to introduce maspin in cancer cell and gene therapy capable of up-regulating the maspin in an attempt to reduce primarily the risk of metastasis.

Further studies in these directions are necessary to better define the therapeutic implication of maspin.

Accessories to the crime: functions of cells recruited to the tumor microenvironment

Mutationally corrupted cancer (stem) cells are the driving force of tumor development and progression. Yet, these transformed cells cannot do it alone. Assemblages of ostensibly normal tissue and bone marrow-derived (stromal) cells are recruited to constitute tumorigenic microenvironments. Most of the hallmarks of cancer are enabled and sustained to varying degrees through contributions from repertoires of stromal cell types and distinctive subcell types. Their contributory functions to hallmark capabilities are increasingly well understood, as are the reciprocal communications with neoplastic cancer cells that mediate their recruitment, activation, programming, and persistence. This enhanced understanding presents interesting new targets for anticancer therapy.

Protease activated receptor-1 inhibits the Maspin tumor-suppressor gene to determine the melanoma metastatic phenotype

The thrombin receptor protease activated receptor-1 (PAR-1) is overexpressed in metastatic melanoma cell lines and tumor specimens. Previously, we demonstrated a significant reduction in tumor growth and experimental lung metastasis after PAR-1 silencing via systemic delivery of siRNA encapsulated into nanoliposomes. Gene expression profiling identified a 40-fold increase in expression of Maspin in PAR-1-silenced metastatic melanoma cell lines. Maspin promoter activity was significantly increased after PAR-1 silencing, suggesting that PAR1 negatively regulates Maspin at the transcriptional level. ChIP analyses revealed that PAR-1 decreases binding of Ets-1 and c-Jun transcription factors to the Maspin promoter, both known to activate Maspin transcription. PAR-1 silencing did not affect Ets-1 or c-Jun expression; rather it resulted in increased expression of the chromatin remodeling complex CBP/p300, as well as decreased activity of the CBP/p300 inhibitor p38, resulting in increased binding of Ets-1 and c-Jun to the Maspin promoter and higher Maspin expression. Functionally, Maspin expression reduced the invasive capability of melanoma cells after PAR-1 silencing, which was abrogated after rescuing with PAR-1. Furthermore, tumor growth and experimental lung metastasis was significantly decreased after expressing Maspin in a metastatic melanoma cell line. Moreover, silencing Maspin in PAR-1-silenced cells reverted the inhibition of tumor growth and experimental lung metastasis. Herein, we demonstrate a mechanism by which PAR-1 negatively regulates the expression of the Maspin tumor-suppressor gene in the acquisition of the metastatic melanoma phenotype, thus attributing an alternative function to PAR-1 other than coagulation.

Maspin, VEGF and p53 expression in small biopsies of primary advanced lung cancer and relationship with clinicopathologic parameters

Maspin, one of the serine protease inhibitors, has been shown to inhibit tumor progression and metastasis. We aimed to investigate maspin, p53 and VEGF expression in patients with squamous cell carcinoma (SCC), adenocarcinoma (AC) and small cell lung carcinoma (SCLC). The study included 28 SCC, 18AC, 17 SCLC biopsy samples. We used the streptavidin biotin immunoperoxidase method to test for maspin, p53 and VEGF antibodies. Medical records of these patients were reviewed from archival files. Cytoplasmic maspin expression was detected in 89.3%, 77.8%, 52.9% of SCC, AC and SCLC, respectively. The rate was significantly higher in non-small cell lung cancer (NSCLC) and SCC than SCLC (p = 0.013, p = 0.021, respectively). The mean percentages of maspin expression were significantly higher in NSCLC, SCC and AC than in SCLC (p = 0.0001, p = 0.0001, p = 0.038, respectively). In ACs, maspin and p53 expressions were correlated, although this was not statistically significant (p = 0.053, r = 0.464), and maspin positive cases had a significantly higher T status compared to negative cases (p = 0.036). In SCC, the stage of disease was positively correlated with p53 (p = 0.007, r = 0.536) and negatively correlated with VEGF expression (p = 0.013, r = -0.498). Multivariate analysis demonstrated that stage of disease was a significant independent prognostic parameter in NSCLC (95% confidence interval: 1.067-3.969; p = 0.031). Although maspin expression is higher in SCC and AC, and is related with higher T status in AC, our data did not indicate its prognostic significance. Larger scale studies are needed to reveal the exact role of maspin in lung cancer pathogenesis.

Maspin expression in gastrointestinal stromal tumors

Background

To investigate the role of maspin expression in the progression of gastrointestinal stromal tumors, and its value as a prognostic indicator.

Methods

In the study 54 patients with GIST diagnosis were included in Uludag University of Faculty of Medicine, Department of Pathology between 1997-2007. The expression of maspin in 54 cases of gastrointestinal stromal tumor was detected by immunohistochemistry and compared with the clinicopathologic tumor parameters.

Results

The positive expression rates for maspin in the GISTs were 66,6% (36 of 54 cases). Maspin overexpression was detected in 9 of 29 high risk tumors (31%) and was significantly higher in very low/low (78.6%) and intermediate-risk tumors (63.6%) than high-risk tumors.

Conclusions

Maspin expression might be an important factor in tumor progression and patient prognosis in GIST. In the future, larger series may be studied to examine the prognostic significance of maspin in GISTs and, of course, maspin expression may be studied in different mesenchymal tumors.

High expression levels of IKKalpha and IKKbeta are necessary for the malignant properties of liver cancer

IKK-NF-kappaB signaling is regarded as an important factor in hepatocarcinogenesis and a potential target for liver cancer therapy. Therefore, in this study, we analyzed the expression of mRNAs encoding components and targets of NF-kappaB signaling including IKKalpha, IKKbeta, RANK, RANKL, OPG, CyclinD3, mammary serine protease inhibitor (Maspin), CyclinD1, c-FLIP, Bcl-xl, Stat3, Cip1 and Cip2 by real-time PCR in 40 patients with liver cancer. After statistical analysis, 7 indices including IKKalpha, IKKbeta, RANK, Maspin, c-FLIP, Cip2 and cyclinD1 were found to show significant differences between tumor tissue and its corresponding adjacent tissue. When IKKalpha and IKKbeta were downregulated in the hepatocellular carcinoma (HCC) cell lines of MHCC-97L and MHCC-97H in vitro, the numbers of BrdU positive cells were decreased in both IKKalpha and IKKbeta knockdown cells. Levels of apoptosis were also investigated in IKKalpha and IKKbeta knockdown cells. The growth of HCC was inhibited in the subcutaneous implantation model, and lung metastatogenesis was also significantly inhibited in the kidney capsule transplantation model. Downregulation of IKKalpha and IKKbeta in HCC cultured in vitro revealed that increased Maspin, OPG and RANKL expression was associated with metastasis of HCC. These findings were associated with downregulation of Bcl-XL and c-FLIP, which may be the reason for increased apoptosis. The therapeutic effect of IKKalpha and IKKbeta downregulation depends on extent of NF-kappaB inhibition and the malignant nature of the HCC. We anticipate that IKK-targeted gene therapy can be used in the treatment of HCC, a cancer that is notoriously resistant to radiation and chemotherapy.

LYR71, a derivative of trimeric resveratrol, inhibits tumorigenesis by blocking STAT3-mediated matrix metalloproteinase 9 expression

Tumor migration/invasion is the main cause of tumor progression and STAT3 is needed to enhance tumor migration/invasion by up-regulating MMP-9. Thus, agents that inhibit STAT3 activation may be used as an anticancer drug. We present herein that 6-methyl-2-propylimino-6, 7-dihydro-5H-benzo [1, 3]-oxathiol- 4-one (LYR71) , a derivative of trimeric resveratrol, has an anticancer activity through inhibition of STAT3 activation. We found that LYR71 suppressed STAT3 activation and inhibited the expression and activity of MMP-9 in RANTES-stimulated breast cancer cells. In addition, LYR71 reduced RANTES-induced MMP-9 transcripts by blocking STAT3 recruitment, dissociating p300 and deacetylating histone H3 and H4 on the MMP-9 promoter. Furthermore, LYR71 inhibited tumor migration/invasion in RANTES-treated breast cancer cells and consequently blocked tumor progression in tumor-bearing mice. Taken together, the results of this study suggest that LYR71 can be therapeutically useful due to the inhibition effect of STAT3-mediated MMP-9 expression in breast cancer cells.

Identification of differential gene expression during porcine conceptus rapid trophoblastic elongation and attachment to uterine luminal epithelium

Early embryonic development in the pig is characterized by a rapid elongation of the conceptus trophectoderm on days 11-12 of gestation. Initially, the conceptus trophoblast is morphologically rearranged from a 10-mm sphere into a tubular shape, transitioning into a thin filamentous form >150 mm in length in 2-3 h, followed by continued expansion within the uterine lumen for several days. Conceptus elongation is critical for establishing adequate placental surface area needed for embryo and fetal survival throughout gestation. The objective of this study was to characterize conceptus gene expression during trophoblastic elongation and the early attachment to the uterine endometrium on days 11-14 of gestation with the GeneChip Porcine Genome Array. In all, 3,759 different probe sets were statistically different in at least one comparison [spherical vs. tubular, spherical vs. day 12 filamentous (D12F), spherical vs. day 14 filamentous (D14F), tubular vs. D12F, tubular vs. D14F, and D12F vs. D14F]. When restricted to the spherical vs. D12F and D12F vs. D14F comparisons, 482 and 232 genes, respectively, were statistically different with greater than twofold change in expression. Utilization of k-means clustering, in addition to the Database for Annotation, Visualization, and Integrated Discovery (DAVID), identified genes of interest. Quantitative RT-PCR expression profiles for interferon-gamma (IFNG), heat shock protein 27 kDa (HSPB1), angiomotin, B-cell linker (BLNK), chemokine ligand 14 (CXCL14), parathyroid hormone-like hormone (PTHLH), and maspin were supportive of the GeneChip Porcine Genome Array data.

Expression of differential genes during hepatocarcinogenesis

AIM: To investigate the gene expression profiles in tissues of normal human liver, chronic hepatitis B, cirrhosis and hepatocellular carcinoma (HCC) by oligonucletide chip, and to screen HCC-related genes.

METHODS: The total RNA was extracted and reverse transcribed into double-strand cDNA, and then transcribed into biotin-labled cRNA target probes. The probes were hybridized with oligonucleotide chip containing 19378 genes respectively. Subsequently, the signal images were scanned by gene Scanner 3000 and analyzed with GenePix Pro 3.0 software.

RESULTS: Eighty-one genes differentially expressed among tissues of chronic hepatitis B, cirrhosis and HCC were screened out in the gene expression profiles. Of the 81 genes, 53 genes were consistently up-regulated, while 28 genes were consistently down-regulated.

CONCLUSION: The oligonucleotide chip of gene expression profile is powerful for screening HCC-related genes. Our results indicate that multiple genes take part in the carcinogenesis of HCC.

Immune cells as mediators of solid tumor metastasis

Outgrowths of disseminated metastases remain the primary cause of mortality in cancer patients; however, molecular and cellular mechanisms regulating metastatic spread remain largely elusive. Recent insights into these mechanisms have refined the seed and soil hypothesis and it is now recognized that metastasis of solid tumors requires collaborative interactions between malignant cells and a diverse assortment of "activated" stromal cells at both primary and secondary tumor locations. Specifically, persistent pro-tumor immune responses (inflammation), now generally accepted as potentiating primary tumor development, are also being recognized as mediators of cancer metastasis. Thus, novel anti-cancer therapeutic strategies targeting molecular and/or cellular mechanisms regulating these collaborative interactions may provide efficacious relief for metastatic disease. This review focuses on recent literature revealing new mechanisms whereby immune cells regulate metastatic progression, with a primary focus on breast cancer.

Maspin Expression in Oral Squamous Cell Carcinoma

Maspin (mammary serine protease inhibitor) is a member of the serpin superfamily of protease inhibitors and it has a role as a tumor suppressor. Maspin has been reported to be important in processes relevant to tumor growth and metastasis such as cell invasion, angiogenesis, and apoptosis. A high expression of maspin was correlated with better rates of survival and absence of nodal metastases in head and neck squamous cell carcinoma. In contrast, some studies have shown that maspin overexpression is correlated with a poor prognosis in pancreatic and ovarian cancers and in lung adenocarcinoma. The aim of this study was an immunohistochemical evaluation of the maspin expression in oral squamous cell carcinoma and thus 89 patients were evaluated. Maspin expression in oral squamous cell carcinoma was significantly associated with the tumor differentiation grade (chi test: P = 0.0318) and the lymph node status (chi test: P < 0.005), but not with the tumor stage (chi test: P = 0.666). Metastatic involvement of lymph nodes was observed more frequently in maspin-negative cases than in tumors with more than 5% of positive cells (P = 0.0024). The present results confirm that maspin expression predicts a better prognosis in oral squamous cell carcinoma and that maspin probably plays a role in tumor progression.

Paradoxical expression of maspin in gastric carcinomas: correlation with carcinogenesis and progression

Maspin, a serine protease inhibitor related to the serpin family, can suppress invasion and metastasis of malignancies. To clarify the role of maspin in the genesis and progression of gastric carcinomas, its expression pattern and level were studied by immunohistochemistry on tissue microarrays containing gastric carcinoma (n = 237), normal gastric mucosa (n = 23), intestinal metaplasia (n = 38), and adenoma (n = 42); and the findings were compared with clinicopathological parameters. Furthermore, maspin expression in the gastric carcinoma cell lines (HCG-27, MKN28, and MKN45) was examined by immunohistochemistry and Western blotting. We found that cytoplasmic and nuclear maspin expression paralleled each other (P < .05) and decreased from intestinal metaplasia, adenoma, and carcinoma to normal gastric mucosa (P < .05). A significant positive association was noted with depth of invasion, lymphatic invasion, lymph node metastasis, and TNM stage (P < .05) but not with sex or Lauren's classification (P > .05). Univariate and multivariate analyses indicated that expression of maspin correlated negatively with cumulative patient survival in gastric carcinoma (P < .05) but was not an independent factor in the prognosis. The 2 independent factors, depth of invasion and lymphatic invasion, influenced the relation between nuclear maspin expression and survival, whereas only depth of invasion correlated with cytoplasmic maspin. Our study indicated that maspin expression experiences upregulation in gastric precancerous lesions and then slight downregulation with malignant transformation. High expression may paradoxically promote invasion and metastasis of gastric carcinomas and could be considered a good marker for the pathobiological behaviors of gastric carcinomas.

Nuclear cytokine-activated IKKalpha controls prostate cancer metastasis by repressing Maspin

Inflammation enhances tumour promotion through NF-kappaB-dependent mechanisms. NF-kappaB was also proposed to promote metastatogenesis through epithelial-mesenchymal transition. Yet a mechanistic link between inflammation and metastasis is missing. We identified a role for IkappaB kinase alpha (IKKalpha), activated by receptor activator of NF-kappaB (RANK/TNFRSF11A), in mammary epithelial proliferation during pregnancy. Owing to similarities between mammary and prostate epithelia, we examined IKKalpha involvement in prostate cancer and its progression. Here we show that a mutation that prevents IKKalpha activation slows down CaP growth and inhibits metastatogenesis in TRAMP mice, which express SV40 T antigen in the prostate epithelium. Decreased metastasis correlated with elevated expression of the metastasis suppressor Maspin, the ablation of which restored metastatic activity. IKKalpha activation by RANK ligand (RANKL/TNFSF11) inhibits Maspin expression in prostate epithelial cells, whereas repression of Maspin transcription requires nuclear translocation of active IKKalpha. The amount of active nuclear IKKalpha in mouse and human prostate cancer correlates with metastatic progression, reduced Maspin expression and infiltration of prostate tumours with RANKL-expressing inflammatory cells. We propose that tumour-infiltrating RANKL-expressing cells lead to nuclear IKKalpha activation and inhibition of Maspin transcription, thereby promoting the metastatic phenotype.

FM-test: a fuzzy-set-theory-based approach to differential gene expression data analysis

Background

Microarray techniques have revolutionized genomic research by making it possible to monitor the expression of thousands of genes in parallel. As the amount of microarray data being produced is increasing at an exponential rate, there is a great demand for efficient and effective expression data analysis tools. Comparison of gene expression profiles of patients against those of normal counterpart people will enhance our understanding of a disease and identify leads for therapeutic intervention.

Results

In this paper, we propose an innovative approach, fuzzy membership test (FM-test), based on fuzzy set theory to identify disease associated genes from microarray gene expression profiles. A new concept of FM d-value is defined to quantify the divergence of two sets of values. We further analyze the asymptotic property of FM-test, and then establish the relationship between FM d-value and p-value. We applied FM-test to a diabetes expression dataset and a lung cancer expression dataset, respectively. Within the 10 significant genes identified in diabetes dataset, six of them have been confirmed to be associated with diabetes in the literature and one has been suggested by other researchers. Within the 10 significantly overexpressed genes identified in lung cancer data, most (eight) of them have been confirmed by the literatures which are related to the lung cancer.

Conclusion

Our experiments on synthetic datasets show that FM-test is effective and robust. The results in diabetes and lung cancer datasets validated the effectiveness of FM-test. FM-test is implemented as a Web-based application and is available for free at .

An intracrine view of angiogenesis

Angiogenesis, the generation of new blood vessels from pre-existing vessels, is an integral component of wound healing, responses to inflammation and other physiologic processes. It is also an essential part of tumor growth; in the absence of new vessel formation, tumors cannot expand beyond a small volume. Although much is known about angiogenesis and its regulation, there is no overall theory that describes or explains this process. It is here suggested that the intracrine hypothesis, which ascribes to certain extracellular signaling peptides (whether hormones, growth factors, DNA-binding proteins or enzymes) a role in both intracellular biology and extracellular signaling, can contribute to a more general understanding of angiogenesis. Intracrine factors participate in angiogenesis in the following ways: (1) they can act within the cells that synthesized them (type I intracrine action), (2) they can be secreted and then taken up by their cell of synthesis to act intracellularly (type II intracrine action ), or (3) they can be secreted and internalized by a distant target cell (type III intracrine action). The parallels between the intracrine growth factor mechanisms cancer cells employ in stimulating their own growth and the mechanisms operative in endothelial cell proliferation during angiogenesis ("intracrine reciprocity") are discussed. Collectively, these explorations lead to testable hypotheses regarding the regulation of normal and pathological angiogenesis, and point to similarities between tumor-induced angiogenesis and tissue differentiation.