Expression of E-selectin, integrinβ_1 and immunoglobulin superfamily member in human gastric carcinoma cells and its clinicopathologic significance

AIM： To study the expression levels of E-selectin, integrin β1 and immunoglobulin supperfamily memberintercellular adhesion molecule-1 （ICAM-1） in human gastric carcinoma cells, and to explore the relationship between these three kinds of cell adhesion molecules and gastric carcinoma. METHODS： The serum contents of E-selectin, integrin β1 and ICAM-1 were detected by enzyme-linked immunosorbent assay （ELISA）, in 47 healthy individuals （control group） and in 57 patients with gastric carcinoma （gastric carcinoma group） respectively prior to operation and 7 d after operation. RESULTS： The serum E-selectin, ECAM-1 and integrin β1 were found to be expressed in both control and gastric carcinoma groups. However, they were highly expressed in patients with gastric carcinoma patients before operation or with unresectable tumours. The expression levels of ICAM-1 and integrin β1 were significantly higher in gastric carcinoma patients than in controls （P 〈 0.01）. A comparison of the E-selectin levels between the two groups showed statistically insignificant differnce （P = 0.64）. In addition, the expression levels were all decreased substantially in the postoperative patients subjected to radical resection of the tumours, indicating that the high level expressions of these compounds might be the important factor for predicting the prognosis of these patients. CONCLUSION： Serum E-selectin, ICAM-1 and integrin β1 expression levels are probably related to the metastasis and relapse of gastric cancer.

Low intensity ultrasound-induced apoptosis in human gastric carcinoma cells

AIM： To investigate the low intensity ultrasound （US）- induced apoptosis in human gastric carcinoma cells and its potential mechanism and to suggest a new therapeutic approach to gastric carcinoma. METHODS： Human SGC-7901 gastric carcinoma cells were cultured in vitro and irradiated by low intensity US for 10 min at different intensities with different incubation times after irradiation. Morphologic changes were examined under microscope with trypan blue staining and then the percentage of early apoptotic cells was detected by flow cytometry （FCM） with double staining of fiuorescein isothiocyanate （FITC）- Annexin V/propidium iodide （PI）. Two-dimensional electrophoresis （2DE） was used to get the protein profile and some proteins differently expressed after US irradiation were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. Functional analysis was performed to investigate the mechanism of US-induced cell apoptosis. RESULTS： The percentage of apoptotic cells increased about 10% after US irradiation （12.0 W/cm^2, 12 h culture）, The percentage of early apoptosis and secondary necrosis in the US-irradiated cells increased with the increased US intensity. Moreover, apoptotic cells increased with the increased culture time after US irradiation and reached its maximum at about 12 h.Several new proteins appeared after US irradiation and were up or down regulated more than 2 times. Some heat shock proteins （HSPs） were found to be associated with the signal process simulating the apoptosis of cells. CONCLUSION： Low intensity US could induce apoptosis in human gastric carcinoma cells. US-induced apoptosis is related to US intensity/culture time. US-induced apoptosis may be caspases-dependent and endoplasmic reticulum （ER） stress-triggered apoptosis may also contribute to it. Proteomic experimental system is useful in finding the protein alteration in carcinoma cells after US irradiation, helping to develop a new cancer therapy.

Immunosuppressive tumor microenvironment in gastric signet-ring cell carcinoma

Gastric signet-ring cell carcinoma(GSRCC)is a subtype of gastric cancer with distinct phenotype and high risk of peritoneal metastasis.Studies have shown that early GSRCC has a good prognosis,while advanced GSRCC is insensitive to radiotherapy,chemotherapy or immune checkpoint blockade therapy.With technological advancement of single-cell RNA sequencing analysis and cytometry by time of flight mass cytometry,more detailed atlas of tumor microenvironment(TME)in GSRCC and its association with prognosis could be investigated extensively.Recently,two single-cell RNA sequencing studies revealed that GSRCC harbored a unique TME,manifested as highly immunosuppressive,leading to high immune escape.The TME of advanced GSRCC was enriched for immunosuppressive factors,including the loss of CXCL13+-cluster of differentiation 8+-Tex cells and declined clonal crosstalk among populations of T and B cells.In addition,GSRCC was mainly infiltrated by follicular B cells.The increased proportion of SRCC was accompanied by a decrease in mucosaassociated lymphoid tissue-derived B cells and a significant increase in follicular B cells,which may be one of the reasons for the poor prognosis of GSRCC.By understanding the relationship between immunosuppressive TME and poor prognosis in GSRCC and the underlying mechanism,more effective immunotherapy strategies and improved treatment outcomes of GSRCC can be anticipated.

Poorly cohesive cells gastric carcinoma including signet-ring cell cancer:Updated review of definition,classification and therapeutic management

While the incidence of gastric cancer(GC)in general has decreased worldwide in recent decades,the incidence of diffuse cancer historically comprising poorly cohesive cells-GC(PCC-GC)and including signet ring cell cancer is rising.Literature concerning PCC-GC is scarce and unclear,mostly due to a large variety of historically used definitions and classifications.Compared to other histological subtypes of GC,PCC-GC is nevertheless characterized by a distinct set of epidemiological,histological and clinical features which require a specific diagnostic and therapeutic approach.The aim of this review was to provide an update on the definition,classification and therapeutic strategies of PCC-GC.We focus on the updated histological definition of PCC-GC,along with its implications on future treatment strategies and study design.Also,specific considerations in the diagnostic management are discussed.Finally,the impact of some recent developments in the therapeutic management of GC in general such as the recently validated taxane-based regimens(5-Fluorouracil,leucovorin,oxaliplatin and docetaxel),the use of hyperthermic intraperitoneal chemotherapy as well as pressurized intraperitoneal aerosol chemotherapy and targeted therapy have been reviewed in depth for their relative importance for PCC-GC in particular.

Update on diagnosis and treatment of early signet-ring cell gastric carcinoma: A literature review

Gastric signet-ring cell gastric carcinoma(GSRC)is an unfavorable subtype of gastric cancer(GC)that presents with greater invasiveness and poorer prognosis in advanced stage than other types of GC.However,GSRC in early stage is often considered an indicator of less lymph node metastasis and more satisfying clinical outcome compared to poorly differentiated GC.Therefore,the detection and diagnosis of GSRC at early stage undoubtedly play a crucial role in the management of GSRC patients.In recent years,technological advancement in endoscopy including narrow-band imaging and magnifying endoscopy has significantly improved the accuracy and sensitivity of the diagnosis under endoscopy for GSRC patients.Researches have confirmed that early stage GSRC that meets the expanded criteria of endoscopic resection showed comparable outcomes to surgery after receiving endoscopic submucosal dissection(ESD),indicating that ESD could be considered standard treatment for GSRC after thorough selection and evaluation.This article summarizes the current knowledge and updates pertaining to the endoscopic diagnosis and treatment of early stage signet-ring cell gastric carcinoma.

DIFFERENCES IN EXPRESSION AND REGULATION BETWEEN TRANSFORMED CELLS OF THE HUMAN GASTRIC CARCINOMA ONCOGENE Ha-ras AND THE UNTRANSFORMED PARENT CELLS

An Ha-ras oncogene was isolated from a cell line of gastric carcinoma called BGE-823 in order to elucidate genetic control and the influence of DNA sequences. The oncogene was cloned and identified as a single nucleotide substitution of thymine for guanine in the 12th codon through the sequencing of its first axon. We compared the differences of expression and regulation between the transformed Ha-ras cells and untransformed parent cells. Data indicated that the expression of Ha-ras in the transformed cells was five-fold higher than in the untransformed cells and that the Ha-ras gene in the former was hypersensitive toward DNase I. In addition, a nuclear protein of 35 kilodaltons bound strongly to the 2.5 Kb fragment located upstream of the 6.6 Kb Ha-ras gene and contained a CC rich region. These results suggest that there might be another mechanism of activation for the ras gene besides point mutation.

IMMUNOHISTOCHEMICAL STUDY ON S100 PROTEIN-POSITIVE DENDRITIC CELLS IN PATIENTS WITH GASTRIC CARCINOMA

The density of dendritic cells (DC) and macro-phages (Mφ) in tissue specimens of gastric carcinoma (GC n=65) was investigated by ABC im-munohistochemical method using anti-S100 protein and anti-lysozyme antibodies, and was compared with that in gastric ulcer (GU n=19), chronic atrophic gastritis (CAG n=28) and normal gastric mucosa (NGM n=15). The mean density if DC (cells/mm2) in GC (15.0 was significantly higher than that in NGM (3.8) and GU (8.3), but was remarkably lower when compared to that in CAG (29.5) (P<0.01). Statistically significant difference in the population density of DC was observed between well- and poorly-differentiated GC (P<0.01). With their unique dendritic processes, DC were mainly concentrated within dense lymphoid infiltrates or in the T-area of reactive lymphoid follicles and were interspersed among the tumor cells. In contrast, Mφ were present around the necrotic foci and were rarely seen within the non-necrotic neoplastic tissues. These data suggest that DC, which differ in morphology, distribution, number and function form Mφ may be more directly involved in the host immune reaction against tumor by acting as antigen presenting cells.

Inhibition of human gastric carcinoma cell growth by atofluding derivative N_3-o-toluyl-fluorouracil

AIM： To evaluate the growth inhibition efficacy of atofluding derivative N3-o-toluyl-fluorouracil （TFU） on human gastric carcinoma cell lines SGC-7901 and MKN-45. METHODS： Cell growth inhibition by TFU was measured by MTT and clonogenic assays without or with liver microsomal enzymes. Xenografts of cancer cells in nude mice were employed to study the anti-proliferative effects of TFU in vivo. RESULTS： TFU inhibited the growth of SGC-7901 and MKN-45 cells. However, the inhibitory effects of TFU on cell growth were not significant. The inhibition rates were enhanced in the presence of liver microsomal enzymes, ranging 4.73%-48.57% in SGC-7901 cells and 9.0%-62.02% in MKN-45 cells. In v/vo, TFU delayed the growth of SGC-7901 and MKN-45 cells in nude mice. The inhibition rates were 40.49%, 63.24%, and 75.98% in SGC-7901 cells and 40.76%, 61.41%, and 82.07% in MKN-45 cells when the oral doses were 25, 50, and 100 mg/kg, respectively. TFU treatment was generally well tolerated by mice with less than 20% reduction in body weight. CONCLUSION： TFU inhibits the growth of human gastric carcinoma cells. The inhibition rates are increased in the presence of liver microsomal enzymes. The efficacy of TFU may be associated with the sustaining release of 5-fluorouracil （5-FU） mediated by the enzymes.

Study of Sonic hedgehog signaling pathway related molecules in gastric carcinoma

AIM： To study the expression of Sonic hedgehog pathway-related molecules, Sonic hedgehog （Shh） and Glil in gastric carcinoma. METHODS： Expression of Shh in 56 gastric specimens including non-cancerous gastric tissues, gastric adenocarcinoma, gastric squamous cell carcinoma was detected by RT-PCR, in situ hybridization and immunohistochemistry. Expression of Glil was observed by in situ hybridization. RESULTS： The positive rate of Shh and Glil expression was 0.0%, 0.0% in non-cancerous gastric tissues while it was 66.7%, 57.8% respectively in gastric adenocarcinoma, and 100%, 100% respectively in gastric squamous cell carcinoma. There was a significant difference between the non-cancerous gastric tissues and gastric carcinoma （P 〈 0.05）. Elevated expression of Shh and Glil in gastric tubular adenocarcinoma was associated with poorly differentiated tumors while the expression was absent in gastric mucinous adenocarcinoma. CONCLUSION： The elevated expression of Shh and Glil in gastric adenocarcinoma and gastric squamous cell carcinoma shows the involvement of activated Shh signaling in the cellular proliferation of gastric carcinogenesis. It suggests Shh signaling gene may be a new and good target gene for gastric tumor diagnosis and therapy.

Inhibitory effect of Fuzheng Yiliuyin in combination with chemotherapeutics on human gastric carcinoma cell strain

AIM： To study the inhibitory effects of Fuzheng Yiliuyin （Decoction for Suppressing Tumors by Strengthening the Body Resistance） in combination with chemotherapeutics on human gastric carcinoma cell strain. METHODS： Fuzheng Yiliuyin （ZY） combined with various kinds of chemotherapeutics was put into two kinds of cultivated human gastric carcinoma cell strains, then its inhibitory effects on human gastric carcinoma cell strains were determind by the MTT method. Flow cytorneter was used to assay the apoptosis rate, and the ultrastructure of gastric carcinoma cells was observed under transmission electron microscope. RESULTS： Obvious apoptosis was seen in gastric carcinoma cells after treatment with ZY for 72 h. ZY and chemical drugs had synergistic inhibition effects on the cultivated gastric carcinoma cells, but the effects were different on various cell strains. The inhibitory effects of ZY could be strengthened by cytotoxic action and apoptosis. ZY combined with tluorouracil, etoposide and cisplatin （EFP） chemotherapeutics had better inhibitory effects on SGC-7901, while ZY combined with EFP or with DDP chemotherapeutics had better inhibitory effects than other drugs on MGC-803. CONCLUSION： ZY induces apoptosis and inhibits the growth of gastric carcinoma cells. ZY has the synergistic function of chemotherapeutics.

Clinicopathological characteristics and prognosis of gastric signet ring cell carcinoma

BACKGROUND The clinicopathological features and prognosis of gastric signet ring cell carcinoma(GSRC)remain controversial,particularly with regard to sensitivity to postoperative adjuvant therapy.AIM To compare the pathological features of GSRC with those of gastric adenocarcinoma of different degrees of differentiation and the differences in survival prognosis between the different disease processes.METHODS By screening gastric cancer patients from 2010 to 2015 in the database of Surveillance,Epidemiology and End Results,and collecting the clinicopathological and prognostic data of gastric cancer patients who underwent surgery from January 2014 to December 2016 in the Second Affiliated Hospital of Nanchang University,we analyzed the general pathological characteristics of GSRC by the chi-square test.Univariate and multivariate analyses were conducted to compare the factors affecting the survival and prognosis of early and advanced gastric adenocarcinoma.The Kaplan-Meier curves were plotted to reveal the survival difference between early and advanced GSRC and different differentiated types of gastric adenocarcinoma.The prognosis model of advanced GSRC was established with R software,and the area under curve(AUC)and C-index were used to assess the accuracy of the model.RESULTS Analysis of pathological features revealed that signet ring-cell carcinoma(SRC)was more frequently seen in younger(<60 years),female,and White patients compared to non-SRC patients.SRC was less commonly associated with early gastric cancer(EGC)(23.60%vs 39.10%),lower N0(38.61%vs 61.03%),and larger tumour sizes>5 cm(31.15%vs 27.10%)compared to the differentiated type,while the opposite was true compared to the undifferentiated type.Survival prognostic analysis found no significant difference in the prognosis of SRC patients among EGC patients.In contrast,among advanced gastric cancer(AGC)patients,the prognosis of SRC patients was correlated with age,race,tumour size,AJCC stage,T-stage,and postoperative adjuvant therapy.The predictive model showed that the 3-year AUC was 0.787,5-year AUC was 0.806,and C-index was 0.766.Compared to non-SRC patients,patients with SRC had a better prognosis in EGC[hazard ratio(HR):0.626,95%confidence interval(CI):0.427-0.919,P<0.05]and a worse prognosis in AGC(HR:1.139,95%CI:1.030-1.258,P<0.05).When non-SRC was divided into differentiated and undifferentiated types for comparison,it was found that in EGC,SRC had a better prognosis than differentiated and undifferentiated types,while there was no significant difference between differentiated and undifferentiated types.In AGC,there was no significant difference in prognosis between SRC and undifferentiated types,both of which were worse than differentiated types.A prognostic analysis of postoperative adjuvant therapy for SRC in patients with AGC revealed that adjuvant postoperative radiotherapy or chemotherapy significantly improved patient survival(34.6%and 36.2%vs 18.6%,P<0.05).CONCLUSION The prognosis of SRC is better than that of undifferentiated type,especially in EGC,and its prognosis is even better than that of differentiated type.SRC patients can benefit from early detection,surgical resection,and aggressive adjuvant therapy.

Primary gastric signet ring cell carcinoma presenting as cardiac tamponade

Primary gastric signet ring cell carcinoma presenting as cardiac tamponade is difficult to diagnosis early. Patients are generally asymptomatic until the disease is advanced. General practitioners usually focus on the initial symptoms related to pericarditis and pericardial effusion. We report a case of signet-ring cell carcinoma of the stomach presenting as cardiac tamponade with pericarditis and pericardial effusion but without any gastrointestinal symptoms. A 49-year old woman was admitted because of progressive dyspnea and cough. Chest X-ray revealed an increased cardiothoracic ratio and a small amount of bilateral pleural effusion. Two dimensional ultrasonographic echocardiography pericardial effusions with atrial and right ventricular early diastolic collapse were found, establishing the diagnosis of cardiac tamponade. Pericardiocentesis was performed and 420 mL of bloody ?uid was taken. The patient died of respiratory failure and cardiac arrest on October 28, 2009. Post-mortem examination revealed diffuse gastric mucosa erosion and edema with stomach mucosa incrassation in the greater curvature. The primary lesion was histopathologically diagnosed as signet-ring cell carcinoma of the stomach.

INTERACTIONS BETWEEN THE HUMAN GASTRIC CARCINOMA CELL AND THE HUMAN VASCULAR ENDOTHELIAL CELL

Objective To definite the interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the establishment and maintenance of the tumor vascular system and the tumor hematogenous metastasis.Methods We prepared the conditioned mediums of each cell so as to study the effect of the conditioned medium on itself or others by MTT colorimetry. The comprehensive effect of interactions between two cells was determined by stratified transfilter co culture or direct contact co culture.Results The conditioned medium of human gastric carcinoma cell can stimulate the proliferation of the human vascular endothelial cell, but the CM of HVEC can inhibit the growth of HGCC. Both kinds of cells can inhibit the growth of itself. The ultimate comprehensive effect of the interactions between two kinds of cells was increase of total cell numbers.Conclusion There exist the complicated interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the tumor angiogenesis and the tumor hematogenous metastasis. The ultimate comprehensive effect of the interactions is increase of total cells numbers and tumor volume.

Chylous ascites arises after chemotherapy of gastric signet ring cell carcinoma: A case report and review

Chylous ascites, a rare clinical condition resulting from the disruption of the abdominal lymphatic system, usually diagnosed by paracentesis when the patients suffer ascites as primary symptom. The conditions, in which chylous ascites arise after chemotherapy of solid tumor, are rarely reported. In this paper we present a quite rare case of chylous ascites arising after chemotherapy of gastric signet ring cell carcinoma.

Gastric signet-ring cell carcinoma with paraneoplastic eosinophilia: A case report and literature review

We report the case of a 40-year-old female Chinese patient with gastric signet-ring cell carcinoma that was first diagnosed because of paraneoplastic eosinophilia.The patient’s eosinophil count reduced markedly to normal levels within 24 h after radical gastrectomy and Billroth II anastomosis.The patient recovered well after the surgery and no abnormalities were found during the regular follow-ups.Paraneoplastic eosinophilia is an unusual manifestation that usually remains asymptomatic;moreover,cases of solid malignant tumors with eosinophilia are uncommon.To our knowledge,this is the first reported case of paraneoplastic eosinophilia in a patient with gastric carcinoma.We considered eosinophilia as a manifestation of a paraneoplastic syndrome,which can be the first clinical manifestation of a malignancy.

N-glycans released from glycoproteins using a commercial kit and comprehensively analyzed with a hypothetical database

The glycosylation of proteins is responsible for their structural and functional roles in many cellular activities.This work describes a strategy that combines an efficient release, labeling and liquid chromatography–mass spectral analysis with the use of a comprehensive database to analyze N-glycans. The analytical method described relies on a recently commercialized kit in which quick deglycosylation is followed by rapid labeling and cleanup of labeled glycans. This greatly improves the separation, mass spectrometry（MS） analysis and fluorescence detection of N-glycans. A hypothetical database, constructed using Glyc Resoft, provides all compositional possibilities of N-glycans based on the common sugar residues found in N-glycans. In the initial version this database contains ＆gt; 8,700 N-glycans, and is compatible with MS instrument software and expandable. N-glycans from four different well-studied glycoproteins were analyzed by this strategy. The results provided much more accurate and comprehensive data than that had been previously reported. This strategy was then used to analyze the N-glycans present on the membrane glycoproteins of gastric carcinoma cells with different degrees of differentiation. Accurate and comprehensive N-glycan data from those cells was obtained efficiently and their differences were compared corresponding to their differentiation states. Thus, the novel strategy developed greatly improves accuracy, efficiency and comprehensiveness of N-glycan analysis.

Polymorphisms in tumor necrosis factor genes and susceptibility to esophageal squamous cell carcinoma and gastric cardiac adenocarcinoma in a population of high incidence region of North China

Background We investigated the possible association of the functional polymorphisms in the tumor necrosis factor （TNF） genes with susceptibility to esophageal squamous cell carcinoma （ESCC） and gastric cardiac adenocarcinoma （GCA）.Methods The TNF-α-308G/A and TNF-β ＋ 252G/A single nucleotide polymorphisms （SNPs） were genotyped using polymerase-chain reaction-restriction fragment length polymorphism （PCR-RFLP） analysis, in 555 cancer patients （291 ESCC and 264 GCA） and 437 healthy controls in a high incidence region of North China. Results Among healthy controls, frequencies of the TNF-α 1/1, 1/2 and 2/2 genotypes were 89.4% ,9.2% and 1.4% respectively, while frequencies of the TNF-β B1/B1, B1/B2 and B2/B2 genotypes were 12.6% , 32.3% and 55.1%, respectively. No significant difference was found in the overall genotype and allelotype distribution of the TNF-α-308G/A and TNF-β ＋ 252G/A SNPs among cancer patients and controls. However, both the B1/B1 genotype and B1/B2 genotype significantly increased the risk of developing ESCC [ the age and gender adjusted odds ratio （OR） =2.04 and 1.91, 95% confidence interval （CI） = 1.04 -4.43 and 1.14 - 2.60, respectively] and GCA （the age and gender adjusted OR =2. 68 and 2. 64, 95% CI = 1.14 -6.29 and 1.47 -4.72, respectively） in individuals with negative family history of UGIC, in comparison with the B2/B2 genotype. When the two TNF polymorphisms were combined and analyzed, individuals with the TNF-β B1/B2 and TNF-α1/2 or 2/2 genotypes significantly reduced the risk of developing ESCC and GCA, in comparison with those harboring the TNF-β B2/B2 and TNF-α 1/1 genotypes （ the age and gender adjusted OR = 0.37 and 0. 34, 95% CI =0. 15 -0.92 and 0. 13 -0.90, respectively）. Conclusions Therefore, the TNF-α -308G/A and TNF-β ＋ 252G/A genotyping may be used as a stratification markers to predicate the risk of ESCC and GCA development in North China.

The cellular and molecular mechanism of laminin glycopeptides on anti -metastasis

To further study the anti metastasis mechanism of laminin glycopeptides on carcinoma cell proliferation, apoptosis and the secretion of matrix metalloproteinases Methods Human hepatocellular carcinoma cells in serum free medium were incubated on laminin coated substrate with or without laminin glycopeptides at a final concentration of 50?μg/ml The total number of surviving cells after incubating for the indicated time was assayed by MTT assay DNA synthesis of the incubated cells was detected by 3H TdR incorporation Cell cycle was analysed by FACS The mitotic index of Giemsa stained cells was assessed Cell apoptosis was detected by both FACS and an acridine orange staining method Matrix metalloproteinase secretion was analysed by gelatin zymography Results The total number of surviving cells incubated on laminin in the absence of laminin glycopeptides was significantly larger than that in the presence of laminin glycopeptides Laminin promoted 3H TdR incorporation of carcinoma cells, decreased the percentage of cells in G1 phase and increased the percentage of cells in S phase In contrast, laminin glycopeptides could inhibit the effect of laminin as shown by 3H TdR incorporation and cell cycle analysis The percentage of cells in G2+M phase and the mitotic index among various groups showed no significant difference Matrix metalloproteinases secretion from cells treated by laminin glycopeptides was much less compared to that without the treatment by laminin glycopeptides Conclusion Laminin may stimulate cell proliferation, while laminin glycopeptides could significantly inhibit the effect of laminin by inhibiting DNA synthesis and arresting the carcinoma cell cycle from G1 to S phase These effects may inhibit not only tumor growth of the primary carcinoma, but also the establishment of metastases at ectopic tissues Laminin glycopeptides could also inhibit the secretion of matrix metalloproteinases from carcinoma cells and this may contribute to their decreased invasive and metastatic phenotype This study further revealed the cellular and molecular mechanism of laminin glycopeptides on anti metastasis