Suppression of matrix metalloproteinase-9 expression by RNA interference inhibits SGC7901 gastric adenocarcinoma cell growth and invasion in vitro and in vivo

The Role of HSPB8, a Component of the Chaperone-Assisted Selective Autophagy Machinery, in Cancer

The cellular response to cancer-induced stress is one of the major aspects regulating cancer development and progression. The Heat Shock Protein B8 (HSPB8) is a small chaperone involved in chaperone-assisted selective autophagy (CASA). CASA promotes the selective degradation of proteins to counteract cell stress such as tumor-induced stress. HSPB8 is also involved in (i) the cell division machinery regulating chromosome segregation and cell cycle arrest in the G0/G1 phase and (ii) inflammation regulating dendritic cell maturation and cytokine production. HSPB8 expression and role are tumor-specific, showing a dual and opposite role. Interestingly, HSPB8 may be involved in the acquisition of chemoresistance to drugs. Despite the fact the mechanisms of HSPB8-mediated CASA activation in tumors need further studies, HSPB8 could represent an important factor in cancer induction and progression and it may be a potential target for anticancer treatment in specific types of cancer. In this review, we will discuss the molecular mechanism underlying HSPB8 roles in normal and cancer conditions. The basic mechanisms involved in anti- and pro-tumoral activities of HSPB8 are deeply discussed together with the pathways that modulate HSPB8 expression, in order to outline molecules with a beneficial effect for cancer cell growth, migration, and death.

Elevated FOXO6 expression correlates with progression and prognosis in gastric cancer

The FOXO6 correlated with tumor progression in a wide range of carcinomas, yet little is known in gastric cancer. The expression of FOXO6 and matrix metallopeptidase 9 (MMP-9) was assessed by immunohistochemistry in 192 gastric carcinoma specimens. The correlation between FOXO6 expression with MMP-9, clinicopathological/prognostic value in gastric cancer was examined. FOXO6 overexpression was significantly associated with depth of invasion, lymph node metastasis and stage of disease. In univariate and multivariate analyses, FOXO6 was an independent prognostic factor for both overall survival (OS) and recurrence-free survival (RFS). Moreover, FOXO6 over-expression was correlated with poor prognosis in patients subgroups stratified by tumor size, depth of invasion and lymph node metastasis. FOXO6 expression was increased in both prominent serosal invasion group and lymph node metastasis group. In addition, FOXO6 expression was positively correlated with MMP-9 among 192 gastric cancer tissues. Patients with FOXO6 over-expression had poor OS and shorter RFS in low and high invasiveness groups. Furthermore, stratified analysis showed that the TNM stage I patients with high FOXO6 expression had poor prognosis than those with low FOXO6 expression. In conclusion, FOXO6 overexpression promotes tumor aggressiveness and prognosis, and could be a promising target for prognostic prediction in gastric cancer patients.

Elevated spondin-2 expression correlates with progression and prognosis in gastric cancer

The spondin-2 correlated with tumor progression in many malignancies. However, the role of spondin-2 in gastric cancer has not been thoroughly elucidated. Spondin-2 and matrix metallopeptidase 9 (MMP-9) expression was detected by immunohistochemistry in 174 gastric carcinoma tissues. The relationship between the expression of spondin-2 and MMP-9, clinicopathological/prognostic value in gastric cancer was examined. Spondin-2 was significantly higher in gastric cancer than that in adjacent non-tumorous tissues. Spondin-2 overexpression was significantly associated with well differentiation, depth of invasion, lymph node metastasis, and advanced TNM stages. The expression levels of spondin-2 were increasing in both prominent serosal invasion group and lymph node metastasis group. In addition, spondin-2 was positively correlated with MMP-9 among 174 gastric cancer samples. In univariate and multivariate analyses, spondin-2 was an independent prognostic factor for both recurrence-free survival (RFS) and overall survival (OS). Moreover, spondin-2 overexpression was associated with poor prognosis in patients with gastric cancer in different risk groups. In conclusion, Spondin-2 overexpression contributes to tumor aggressiveness and prognosis, and could be a promising target for prognostic prediction in gastric cancer patients.

Integrin-Linked Kinase Silencing Induces a S/G2/M Phases Cell Cycle slowing and Modulates Metastasis-Related Genes in SGC7901 Humancc Gastric Carcinoma Cells

Background and aim

Integrin-linked kinase has been implicated in metastasis of human tumors. Recent studies have also shown that the down-regulation of integrin-linked kinase has anti-tumor potential by inhibiting the metastatic potential of several types of cultured human cancer cells. However, the mechanism by which integrin-linked kinase regulates metastasis in human gastric carcinoma is not fully clear. We investigated the effect of integrin-linked kinase deletion on metastasis-associated markers in human gastric carcinoma SGC-7901 cell lines.

Methods

We generated cell lines depleted for integrin-linked kinase. Cell adhesion and invasion were measured by the MTS assay and transwell assay. The cell cycle was measured by flow cytometry. Expression of metastasis-related genes was assessed by reporter assay, quantitative RT-PCR and western blotting.

Results

Our data showed an inhibitory effect on cell adhesion and invasion after silencing of integrin-linked kinase. The cell cycle was slowed in S/G2/M phases. Metastasis-related genes E-cadherin, MMP-2/9 and cystatin B, as well as the signaling molecules p-Akt, NF-κB, and AP-1 activation, were also modulated. Our results indicate that integrin-linked kinase plays an important role in metastasis of human gastric carcinoma cells.

Conclusions

Down-regulation of integrin-linked kinase resulted in the impairment of the metastatic potential of gastric tumor cells by regulating metastasis-related gene expression, by inhibiting the Akt pathway as well as the activity of transcription factors. Integrin-linked kinase could be used as a potential therapeutic target.

MMP2 and MMP7 at the invasive front of gastric cancer are not associated with mTOR expression

Background

Regulation of MMP expression by activation of mTOR signalling has been demonstrated for several tumor types, but has thus far not been confirmed in gastric cancer.

Findings

The study compromised 128 patients who underwent gastric resection for cancer (66.4 % male; 86 intestinal, 42 diffuse type). Immunohistochemical staining of MMPs was performed to analyse the topographical pattern of MMP expression at the tumor center and the invasive front, respectively. MMP2 showed higher expression at the invasive front compared to the tumor center, whereas MMP7 staining scores were higher in the tumor center, and there was no difference for MMP9. The expression of p-mTOR was higher in the tumor center than at the invasive front, with a similar trend for mTOR. For intestinal type gastric cancer there was a weak correlation of MMP9 with expression of mTOR in the tumor center. Otherwise, there was no correlation of the MMPs with mTOR. By treatment of MKN45 gastric cancer cells with rapamycin, a reduction of p-mTOR in the Western blot was achieved; however, expression of MMPs remained unaffected.

Conclusions

Expression of MMP2 and MMP7 in gastric cancer is not associated with mTOR, MMP9 expression might be related to mTOR signalling in a subset of tumors.

Electronic supplementary material

The online version of this article (doi:10.1186/s13000-015-0449-z) contains supplementary material, which is available to authorized users.

A Gelatinases-targeting scFv-based Fusion Protein Shows Enhanced Antitumour Activity with Endostar against Hepatoma

Gelatinases play important roles in tumour invasion and metastasis and are thus considered promising targets for cancer therapy. In this study, a new single-chain variable fragment (scFv)-based fusion protein Fv-LDP, composed of the anti-gelatinases scFv and lidamycin apoprotein (LDP), was prepared, and its combination with angiogenesis inhibitor Endostar was then investigated. The fusion protein Fv-LDP specifically bound to various tumour cells, and its binding capability to human pulmonary giant cell carcinoma (PG) cells was higher than that of LDP. Fv-LDP inhibited the expression and secretion of gelatinases and could be internalized into tumour cells via endocytosis. Fv-LDP also suppressed the growth of human hepatoma cells and murine hepatoma 22 transplanted in Kunming mice in various degrees. In addition, Endostar could enhance the synergistic or additive inhibition of Fv-LDP on the growth, migration or invasion of human hepatoma cells shown by a colony formation assay and a transwell-based migration or invasion assay, respectively. In vivo, Fv-LDP/Endostar combination showed a significantly synergistic effect on the growth of a human hepatoma xenograft, with an inhibition rate of 80.8% compared with the Fv-LDP (44.1%) or Endostar (8.9%)-treated group. The above-mentioned results indicate that the fusion protein Fv-LDP is effective against transplantable hepatoma in mice and human hepatoma xenografts in athymic mice. Moreover, Endostar can potentiate the inhibition effect of Fv-LDP on the growth of human hepatoma cells and xenografts. These data will provide a new combined strategy for improving the therapeutic efficacy of treatments for hepatoma or other gelatinase-overexpressing tumours.

ALDH1A1 overexpression is associated with the progression and prognosis in gastric cancer

BACKGROUND

Aldehyde dehydrogenase 1 family member A1 (ALDH1A1) is a cancer stem cell marker, and its expression correlates with prognosis in a number of malignancies. The aim of this study is to determine the relationship of ALDH1A1 expression with clinicopathological parameters and prognosis in gastric cancer.

METHODS

ALDH1A1 and matrix metallopeptidase 9 (MMP-9) was evaluated by immunohistochemistry in 216 gastric carcinoma samples. The association between expression of ALDH1A1 and MMP-9, clinicopathological parameters, and prognosis of gastric cancer was examined.

RESULTS

ALDH1A1 protein expression was significantly associated with depth invasion, lymph node metastasis and stage of disease (all P<0.05). Both univariate and multivariate analyses revealed that ALDH1A1 was an independent prognostic factor for both overall survival (OS) and recurrence-free survival (RFS) (both P<0.001). Furthermore, ALDH1A1 overexpression was associated with poor prognosis in patients subgroups stratified by tumor size, depth invasion and lymph node metastasis. Moreover, ALDH1A1 was significantly correlated with MMP-9 among 216 gastric cancer tissues (P<0.001). Patients who had ALDH1A1 overexpression, in which tumor cells displayed high invasiveness, had poor OS and shorter RFS.

CONCLUSION

ALDH1A1 plays an important role in tumor aggressiveness and prognosis, and may act as a promising target for prognostic prediction.

Heat shock protein 60 overexpression is associated with the progression and prognosis in gastric cancer

Background

Heat shock protein 60 (HSP60) is a chaperonin with essential functions for cell physiology and survival, and its expression correlates with prognosis in a number of malignancies. The aim of this study is to determine the relationship of HSP60 status with clinicopathological parameters and prognosis in gastric cancer.

Methods

The levels of HSP60 and matrix metallopeptidase 9 (MMP-9) antigen was evaluated by immunohistochemistry in 223 gastric carcinoma samples. The association between HSP60 and MMP-9, clinicopathological parameters, and prognosis of gastric cancer was examined.

Results

The level of HSP60 protein was significantly associated with depth invasion, lymph node metastasis and stage of disease (all P<0.05). Both univariate and multivariate analyses revealed that HSP60 was an independent prognostic factor for both overall survival (OS) and recurrence-free survival (RFS) (both P<0.05). Furthermore, HSP60 overexpression was associated with a poor prognosis in patients with advanced gastric cancer in different risk groups. Moreover, HSP60 was significantly correlated with MMP-9 among 223 gastric cancer tissues (P<0.001). Patients who had HSP60 overexpression, in which tumor cells displayed high invasiveness, had poor OS and shorter RFS.

Conclusion

HSP60 plays an important role on tumor aggressiveness and prognosis, and may act as a promising target for prognostic prediction.

Heat shock protein 22 overexpression is associated with the progression and prognosis in gastric cancer

PURPOSE

The heat shock protein 22 (HSP22) is associated with tumor proliferation and protects tumor cell from apoptosis in many malignancies. However, the role of HSP22 in gastric cancer has not been thoroughly elucidated. The aim was to determine the relationship of HSP22 expression with clinicopathological parameters and prognosis in gastric cancer and estimate the alteration of HSP22 expression after neoadjuvant chemotherapy.

METHODS

HSP22 and matrix metallopeptidase 9 (MMP-9) antigen expressions were evaluated by immunohistochemistry in 129 gastric carcinoma samples. Univariate and multivariate analyses were performed to determine the association between HSP22 expression and prognosis. The response of HSP22 was assessed in 47 patients who received neoadjuvant chemotherapy.

RESULTS

HSP22 protein expression was significantly associated with tumor size, depth invasion, lymph node metastasis and stage of disease (all P < 0.05). In univariate and multivariate analyses, HSP22 was an independent prognostic factor for both overall survival (OS) and recurrence-free survival (RFS) (P = 0.003 and P = 0.004, respectively). Furthermore, HSP22 overexpression was associated with a poor prognosis in all patients and in patients subgroups stratified by tumor size, depth invasion and lymph node metastasis. In addition, HSP22 was significantly correlated with MMP-9 among 129 gastric cancer tissues (P < 0.001). Patients who had MMP-9 overexpression had poor OS and shorter RFS. Moreover, the alteration of HSP22 was not comparable in 47 patients who underwent neoadjuvant chemotherapy.

CONCLUSIONS

HSP22 plays an important role on tumor aggressiveness and prognosis and may act as a promising target for prognostic prediction.

Proliferin-related protein overexpression in SGC‑7901 gastric cancer cells inhibits in vitro cell growth and tumorigenesis in nude mice

As reported in the literature, the worldwide 5-year overall survival rate for patients with gastric cancer receiving surgical treatment in the progressive stage is less than 25%. Therefore, there is an urgent need for the development of novel therapeutic strategies. Our preliminary studies demonstrated that proliferin-related protein (PRP) inhibits the proliferation of TM3 Leydig testicular cells. To evaluate whether PRP has antitumor effects in vitro and in vivo, we stably expressed PRP in SGC-7901 gastric carcinoma cells. PRP inhibited the proliferation and cell cycle progression of SCG-7901 cells, as determined by cell growth and cell cycle assays. Transwell experiments demonstrated that PRP inhibited the cell migration and invasion of SCG-7901 cells. Western blotting demonstrated that PRP-overexpressing cells had upregulated matrix metalloproteinase 9 (MMP-9) and downregulated tissue inhibitor of metalloproteinases-1 (TIMP-1). In a xenograft tumor formation assay using nude mice, tumors formed by PRP-overexpressing cells had significantly lower weights than those formed by control cells, and the tumor inhibitory rate reached 71.9%. We demonstrated for the first time that PRP inhibits gastric carcinoma cell proliferation, motility, and tumorigenicity in vivo, suggesting that PRP may become an important target for the development of gastric cancer gene therapy.

Downregulated microRNA-200a promotes EMT and tumor growth through the wnt/β-catenin pathway by targeting the E-cadherin repressors ZEB1/ZEB2 in gastric adenocarcinoma

In a previous study, we found that microRNA (miRNA)-200a suppresses Wnt/β-catenin signaling by interacting with β-catenin, thereby inhibiting migration, invasion and proliferation. However, the mechanism involved in this suppression remains unclear. In the present study, we investigated the underlying mechanism of miR-200a regulation of epithelial-mesenchymal transition (EMT) in gastric carcinoma cells, and confirmed the tumor suppressor role of miR-200a in vivo. The expressions of miRNA-200a, -200b and -200c, identified by fluorescent in situ hybridization, were downregulated and inversely correlated with WHO grades of gastric adenocarcinoma (GA). The expression of the potential miR-200a target genes ZEB1 and ZEB2 was detected immunohistochemically. These examinations used the same tissue microarrays to analyze the relationships between miR-200a and potential target genes. The expression of miR-200a and ZEB1/ZEB2 in the same GA tissue microarrays was inversely related. Restored miR-200a expression inhibited tumor growth in nude mice harboring subcutaneous SGC7901 xenografts. The expression of N-cadherin, β-catenin, Twist1 and Snail2 decreased, and E-cadherin levels increased, when miR-200a was elevated, as tested by fluorescence microscopy and immunohistochemistry. Similar results were observed in vivo. We found upregulated miR-200a expression to increase E-cadherin and suppress the Wnt/β-catenin pathway by targeting ZEB1 and ZEB2 in GA, thus delaying tumor growth in vivo. The effect of miR-200a on Wnt/β-catenin signaling may provide a therapeutic target against EMT.

Silencing phospholipid scramblase 1 expression by RNA interference in colorectal cancer and metastatic liver cancer

BACKGROUND

Phospholipid scramblase 1 (PLSCR1) not only participates in the transbilayer movement of phospholipids, but also plays a role in the pathogenesis and progression of cancers. The present study aimed to evaluate the effect of silencing PLSCR1 expression by RNA interference in colorectal cancer (CRC) and metastatic liver cancer.

METHODS

The expression of PLSCR1 in CRC and metastatic liver cancer samples was assessed by immunohistochemistry. The cultured cells with the highest expression were selected for subsequent experiments. We designed three siRNA oligonucleotide segments targeted at PLSCR1. Successful transfection was confirmed. The biological behavior of the cells in proliferation, adhesion, migration and invasion was determined.

RESULTS

PLSCR1 protein expression increased significantly in the majority of CRC and metastatic liver cancer samples compared with normal samples. Lovo cells had the highest expression of PLSCR1. The siRNA-390 oligonucleotide segment had the best silencing effect. After transfection, Lovo cell proliferation was significantly inhibited compared with the controls in the MTT assay. Laminin and fibronectin adhesion assays showed Lovo cell adhesion was also significantly inhibited. In the migration assay, the number of migrating cells in the PLSCR1 siRNA-390 group was 50+/-12, significantly lower than the number in the siRNA-N group (115+/-28) and in the control group (118+/-31). In an invasion test, the number of invading cells in the PLSCR1 siRNA-390 group was 60+/-18, significantly lower than that in the siRNA-N group (97+/-26) and the control group (103+/-24).

CONCLUSIONS

PLSCR1 is overexpressed in CRC and metastatic liver cancer. Silencing of PLSCR1 by siRNA inhibits the proliferation, adhesion, migration and invasion of Lovo cells, which suggests that PLSCR1 contributes to the tumorigenesis and tumor progression of CRC. PLSCR1 may be a potential gene therapy target for CRC and associated metastatic liver cancer.

Cancer cell invasion: treatment and monitoring opportunities in nanomedicine

Cell invasion is an intrinsic cellular pathway whereby cells respond to extracellular stimuli to migrate through and modulate the structure of their extracellular matrix (ECM) in order to develop, repair, and protect the body's tissues. In cancer cells this process can become aberrantly regulated and lead to cancer metastasis. This cellular pathway contributes to the vast majority of cancer related fatalities, and therefore has been identified as a critical therapeutic target. Researchers have identified numerous potential molecular therapeutic targets of cancer cell invasion, yet delivery of therapies remains a major hurdle. Nanomedicine is a rapidly emerging technology which may offer a potential solution for tackling cancer metastasis by improving the specificity and potency of therapeutics delivered to invasive cancer cells. In this review we examine the biology of cancer cell invasion, its role in cancer progression and metastasis, molecular targets of cell invasion, and therapeutic inhibitors of cell invasion. We then discuss how the field of nanomedicine can be applied to monitor and treat cancer cell invasion. We aim to provide a perspective on how the advances in cancer biology and the field of nanomedicine can be combined to offer new solutions for treating cancer metastasis.