Expression of hepatocyte growth factor and basic fibroblast growth factor as prognostic indicators in gastric cancer

Gastric Cancer: Identification of microRNAs Inhibiting Druggable Targets and Mediating Efficacy in Preclinical In Vivo Models

In addition to chemotherapy, targeted therapies have been approved for treatment of locally advanced and metastatic gastric cancer. The therapeutic benefit is significant but more durable responses and improvement of survival should be achieved. Therefore, the identification of new targets and new approaches for clinical treatment are of paramount importance. In this review, we searched the literature for down-regulated microRNAs which interfere with druggable targets and exhibit efficacy in preclinical in vivo efficacy models. As druggable targets, we selected transmembrane receptors, secreted factors and enzymes. We identified 38 microRNAs corresponding to the criteria as outlined. A total of 13 miRs target transmembrane receptors, nine inhibit secreted proteins and 16 attenuate enzymes. These microRNAs are targets for reconstitution therapy of gastric cancer. Further target validation experiments are mandatory for all of the identified microRNAs.

Expression of angiogenic growth factors in canine squamous cell cancers

Skin and subcutaneous tissue tumors are the most common neoplasms in dogs. The most common sites of origin in dogs include digits, skin and the oral cavity including cheek and retromandibular area. We investigated canine squamous cell carcinoma (SCC) samples from 15 dogs and classified them histopathologically according to the degree of differentiation. bFGF, VEGF-C, TGF-β, PDGF-A, PDGF-C and PDGFR-α expressions were assessed using immunohistochemistry to determine the roles of growth factors during SCC. We found that TGF-β1 immunolabeling was elevated significantly compared to healthy controls in SCC originating from nailbeds, while expression of other growth factors did not change significantly. Our findings might explain the role of TGF-β1 in the infiltrative and malignant behavior of SCC originating from nailbeds.

Expression levels of angiogenic growth factors in feline squamous cell carcinoma

Squamous cell carcinoma (SCC) is the most common malignant neoplasm of the skin in cats. Tumour angiogenesis is the pivotal event for tumour progression and metastasis. We assessed protein and gene expression of angiogenic growth factors including bFGF, VEGF-C, TGF-β, PDGF-A, PDGF-C and PDGFR-α that possibly contribute to the angiogenic phenotype of feline SCC (FSCC) and could, therefore, be a good target in the treatment of SCC. In the present study, a total of 27 FSCC cases were investigated. Tumour cases were histopathologically classified as well differentiated (10/27), moderately differentiated (5/27), and poorly differentiated (12/27). The expression levels of the growth factors were detected using immunohistochemistry and assessed semi-quantitatively. Growth factor expression levels were evaluated at different locations: in the oral region, in areas exposed to solar UV radiation including the ears, eyelids and nasal planum, and other miscellaneous locations. Our findings have revealed that FSCC arising from different anatomical sites of the body and showing differences in aggressiveness, metastasis, and prognosis may be angiogenesis dependent, and angiogenic key regulators could play a role in the development of FSCC.

Biomarker analyses of second-line ramucirumab in patients with advanced gastric cancer from RAINBOW, a global, randomized, double-blind, phase 3 study

BACKGROUND

The RAINBOW trial showed that second-line ramucirumab with paclitaxel prolongs overall survival (OS) and progression-free survival (PFS) compared with placebo plus paclitaxel for treatment of advanced gastric/gastroesophageal junction cancer. Plasma samples were collected from patients during the trial and tested to identify predictive and prognostic biomarkers.

PATIENTS AND METHODS

Circulating factors in plasma samples from mutually exclusive subsets of RAINBOW patients were assayed using: Intertek assays (24 markers, 380 samples, 57% of patients) and Lilly-developed assay (LDA) platform (5 markers, 257 samples, 39% of patients). Time-trend plots were generated for each marker from the Intertek assays. Baseline patient data were dichotomized into low- and high-marker subgroups. Markers were analyzed for predictive effects using interaction models and for prognostic effects using main-effects models.

RESULTS

The Intertek and LDA populations were representative of the full trial population. Plasma levels of VEGF-D and PlGF increased from baseline levels during treatment, then declined after treatment discontinued. Angiopoietin-2 exhibited a decrease during treatment, then increased after treatment discontinuation. No clear time trend was evident with the other markers. Analyses of baseline biomarker expression and its relationship with efficacy variables found no biomarker was predictive for efficacy outcomes, including VEGF-D. However, CRP, HGF, ICAM-3, IL-8, SAA, and VCAM-1 were identified as potential prognostic markers with low baseline levels corresponding to longer OS and PFS.

CONCLUSIONS

Pharmacodynamic and prognostic relationships were found from the exploratory biomarker analyses in RAINBOW; however, no predictive markers for ramucirumab in gastric cancer were identified in this trial.

Bad phosphorylation as a target of inhibition in oncology

Bcl-2 agonist of cell death (BAD) is a BH3-only member of the Bcl-2 family which possesses important regulatory function in apoptosis. BAD has also been shown to possess many non-apoptotic functions closely linked to cancer including regulation of glycolysis, autophagy, cell cycle progression and immune system development. Interestingly, BAD can be either pro-apoptotic or pro-survival depending on the phosphorylation state of three specific serine residues (human S75, S99 and S118). Expression of BAD and BAD phosphorylation patterns have been shown to influence tumor initiation and progression and play a predictive role in disease prognosis, drug response and chemosensitivity in various cancers. This review aims to summarize the current evidence on the functional role of BAD phosphorylation in human cancer and evaluate the potential utility of modulating BAD phosphorylation in cancer.

Long pentraxin 3: A novel multifaceted player in cancer

Since its discovery in 1992, long pentraxin 3 (PTX3) has been characterized as soluble patter recognition receptor, a key player of the innate immunity arm with non-redundant functions in pathogen recognition and inflammatory responses. As a component of the extra-cellular matrix milieu, PTX3 has been implicated also in wound healing/tissue remodeling, cardiovascular diseases, fertility, and infectious diseases. Consequently, PTX3 levels in biological fluids have been proposed as a fluid-phase biomarker in different pathological conditions. In the last decade, experimental evidences have shown that PTX3 may exert a significant impact also on different aspects of cancer biology, including tumor onset, angiogenesis, metastatic dissemination and immune-modulation. However, it remains unclear whether PTX3 acts as a good cop or bad cop in cancer. In this review, we will summarize and discuss the scientific literature data focusing on the role of PTX3 in experimental and human tumors, including its putative translational implications.

Clinicopathological significance and prognostic role of microvessel density in gastric cancer: A meta-analysis

OBJECTIVE

The aim of this study was to elucidate the clinicopathological significance and prognostic role of microvessel density (MVD) in gastric cancer (GC) through a meta-analysis.

METHODS

This meta-analysis included 4094 patients from 26 eligible studies. We investigated the correlation between MVD and clinicopathological characteristics, including survival rate. In addition, subgroup analysis based on microscopic magnification among evaluation criteria of MVD was performed.

RESULTS

High MVD was significantly correlated with worse overall and disease-free survival rates [hazard ratio (HR), 3.028, 95% confidence interval (CI) 2.105-4.357 and HR 2.045, 95% CI 1.530-2.732, respectively]. MVD was significantly increased in GC with diffuse type of Lauren's classification [mean difference (MD) 3.091, 95% CI 0.615-5.567], lymphatic invasion (MD 8.262, 95% CI 3.310-13.214), lymph node metastasis (MD 5.730, 95% CI 2.444-9.016), higher pT stage (pT3-4) (MD 7.093, 95% CI 0.060-14.126) and higher pTNM stage (III-IV) (MD 3.023, 95% CI 0.181-5.865). However, MD of MVD was not significantly different in regard to vascular invasion (MD 7.430, 95% CI 1.015-15.875), tumor differentiation (MD 5.501, 95% CI 1.353-12.355) and tumor size (MD 4.731, 95% CI 2.003-11.465).

CONCLUSION

Taken together, higher MVD was significantly correlated with worse prognosis. In addition, MVD was significantly higher in GC with aggressive tumor behavior than in GC without aggressive features.

The role of fibroblast growth factor 2 in patients with uterine smooth muscle tumors: an immunohistochemical study

OBJECTIVE

Fibroblast growth factor 2 (FGF-2) is considered to be a potent stimulator of angiogenesis and seems therefore to play an important role in the growth of tumors. We compared the immunohistochemical profile of FGF-2 in patients with uterine leiomyomas, smooth muscle tumors of uncertain malignant potential (STUMP) and leiomyosarcoma (LMS). Furthermore, we tried to clarify the prognostic role of FGF-2 in uterine leiomyosarcoma.

STUDY DESIGN

FGF-2 expression was investigated by immunohistochemistry from paraffin-embedded tissue in 26 patients with leiomyoma, in 24 cases with STUMP and in 21 patients with LMS. The immunohistochemical profile of these 3 tumor entities was compared and regarding LMS correlated with different clinicopathologic parameters.

RESULTS

FGF-2 was expressed in 85% of leiomyomas, in 88% of STUMP and in 57% of LMS. Significant differences regarding the frequency of FGF-2 expression were observed between leiomyoma and LMS as well as between STUMP and LMS (p<0.05). In uterine LMS FGF-2 expression was statistically more frequent in cases with high histological grade (p<0.05). Furthermore, FGF-2 positive tumors demonstrated a statistically significant higher rate of recurrence disease and tumor progression (p=0.005). Disease free as well as overall survival was significantly shortened in patients with FGF-2 positive compared to FGF-2 negative tumors (p<0.05).

CONCLUSION

The significant correlation between FGF-2 expression and high histological grade indicates that FGF-2 might work as a negative predictive factor. Higher rates of recurrence disease as well as shortened disease free and overall survival among FGF-2 positive LMS support the potential role as prognosticator for poor clinical outcome.

Peptidomimetic suppresses proliferation and invasion of gastric cancer cells by fibroblast growth factor 2 signaling cascade blockage

Fibroblast growth factor 2 (FGF2) is closely involved in a variety of tumors, including gastric cancer (GC). FGF2 inhibitors exert good antitumor activity, but no FGF2 inhibitor has been employed for clinical use. To obtain a low-toxicity, stable peptidomimetic (called P29) target to FGF2, the affinity between P29 and FGF2 was detected by surface plasmon resonance. The stability of P29 was measured by high performance liquid chromatography. MTT assay and transwell assay were used to access the proliferative and invasive ability of GC cells, respectively. Western blot assay and flow cytometric analysis were applied to study the mechanism of P29. P29 possessed high affinity with FGF2 and a longer half-life in vitro. P29 suppressed the FGF2-induced proliferation of GC cells. It also inhibited the phosphorylation of FRS2, ERK1/2, and AKT triggered by FGF2 in GC. In addition, P29 blocked GC cell transformation from the G1/G0 phase to the S phase and weakened the invasive capability of GC cells. In this paper, we present a novel FGF2 inhibitor that could exert improved anticancer effect in GC in vitro.

The broad-spectrum anti-DNA virus agent cidofovir inhibits lung metastasis of virus-independent, FGF2-driven tumors

The FDA-approved anti-DNA virus agent cidofovir (CDV) is being evaluated in phase II/III clinical trials for the treatment of human papillomavirus (HPV)-associated tumors. However, previous observations had shown that CDV also inhibits the growth of vascular tumors induced by fibroblast growth factor-2 (FGF2)-transformed FGF2-T-MAE cells. Here, we demonstrate that CDV inhibits metastasis induced by FGF2-driven, virus-independent tumor cells. Pre-treatment of luciferase-expressing FGF2-T-MAE cells with CDV reduced single cell survival and anchorage-independent growth in vitro and lung metastasis formation upon intravenous inoculation into SCID mice. This occurred in the absence of any effect on homing of FGF2-T-MAE cells to the lungs and on the growth of subconfluent cell cultures or subcutaneous tumors in mice. Accordingly, CDV protected against lung metastasis when given systemically after tumor cell injection. Lung metastases in CDV-treated mice showed reduced Ki67 expression and increased nuclear accumulation of p53, indicating that CDV inhibits metastasis by affecting single cell survival properties. The anti-metastatic potential of CDV was confirmed on B16-F10 melanoma cells, both in zebrafish embryos and mice. These findings suggest that CDV may have therapeutic potential as an anti-metastatic agent and warrants further study to select those tumor types that are most likely to benefit from CDV therapy.

LY2875358, a neutralizing and internalizing anti-MET bivalent antibody, inhibits HGF-dependent and HGF-independent MET activation and tumor growth

PURPOSE

MET, the receptor for hepatocyte growth factor (HGF), has been implicated in driving tumor proliferation and metastasis. High MET expression is correlated with poor prognosis in multiple cancers. Activation of MET can be induced either by HGF-independent mechanisms such as gene amplification, specific genetic mutations, and transcriptional upregulation or by HGF-dependent autocrine or paracrine mechanisms.

EXPERIMENTAL DESIGN/RESULTS

Here, we report on LY2875358, a novel humanized bivalent anti-MET antibody that has high neutralization and internalization activities, resulting in inhibition of both HGF-dependent and HGF-independent MET pathway activation and tumor growth. In contrast to other bivalent MET antibodies, LY2875358 exhibits no functional agonist activity and does not stimulate biologic activities such as cell proliferation, scattering, invasion, tubulogenesis, or apoptosis protection in various HGF-responsive cells and no evidence of inducing proliferation in vivo in a monkey toxicity study. LY2875358 blocks HGF binding to MET and HGF-induced MET phosphorylation and cell proliferation. In contrast to the humanized one-armed 5D5 anti-MET antibody, LY2875358 induces internalization and degradation of MET that inhibits cell proliferation and tumor growth in models where MET is constitutively activated. Moreover, LY2875358 has potent antitumor activity in both HGF-dependent and HGF-independent (MET-amplified) xenograft tumor models. Together, these findings indicate that the mechanism of action of LY2875358 is different from that of the one-armed MET antibody.

CONCLUSIONS

LY2875358 may provide a promising therapeutic strategy for patients whose tumors are driven by both HGF-dependent and HGF-independent MET activation. LY2875358 is currently being investigated in multiple clinical studies.

Expression of MACC1 and c-Met in human gastric cancer and its clinical significance

BACKGROUND

Recent studies have suggested that the metastasis-associated colon cancer1 (MACC1) gene can promote tumor proliferation, invasion and metastasis through an upregulation of c-Met expression. However, its role in gastric cancer is controversial. Our study investigated expression of MACC1 and c-Met in gastric cancer, as well as correlated this with clinicopathological parameters.

METHODS

Expressions of MACC1 and c-Met protein in a sample of 98 gastric carcinoma and adjacent nontumorous tissues were detected by immunohistochemistry. Their relationships and correlations with clinicopathological features were analyzed.

RESULTS

The positive rates of MACC1 and c-Met protein in primary tumors were 61.22% and 59.18%, respectively. A significant correlation was found between expression of MACC1 and c-Met (P<0.05). Expression of the MACC1 protein in gastric cancer tissue was correlated with lymph node metastasis (χ2 = 10.555,P = 0.001), peritoneal metastasis (χ2 = 5.694, P = 0.017), and hepatic metastasis (χ2 = 4.540,P = 0.033), but not with age, gender, tumor size, location, clinical stage or the distant metastases (P>0.05).

CONCLUSION

The positive rate of MACC1 protein expression was related to the protein expression of c-Met. Both had a correlation with the presence of peritoneal metastasis, lymph node metastasis and hepatic metastasis, all of which contribute to a poor prognosis for gastric cancer patients.

Hypoxia stimulates the EMT of gastric cancer cells through autocrine TGFβ signaling

Epithelial mesenchymal transition (EMT) is considered to be correlated with malignancy of cancer cells and responsible for cancer invasion and metastasis. We previously reported that distant metastasis was associated with hypoxia in gastric cancer. We therefore investigated the effect of hypoxic condition on EMT of gastric cancer cells. Gastric cancer cells were cultured in normoxia (21% O₂) or hypoxia (1% O₂) for 24 h. EMT was evaluated as the percentage of spindle-shaped cells in total cells. Effect of transforming growth factor β1 (TGFβ1) or tyrosine kinase inhibitors on the EMT was evaluated. The expression level of TGFβ1 and TGFβR was evaluated by real time RT-PCR. The TGFβ1 production from cancer cells was measured by ELISA. Hypoxia stimulated EMT of OCUM-2MD3 and OCUM-12 cells, but not that of OCUM-2M cells. The expression level of TGFβ1 mRNA under hypoxia was significantly higher than that under normoxia in all of three cell lines. The expression level of TGFβR mRNA was significantly increased by hypoxia in OCUM-2MD3 cells, but not in OCUM-2M cells. TGFβR inhibitor, SB431542 or Ki26894, significantly suppressed EMT of OCUM-2MD3 and OCUM-12. TGFβ1 production from OCUM-2MD3 and OCUM-12 cells was significantly increased under hypoxia in comparison with that under normoxia. These findings might suggest that hypoxia stimulates the EMT of gastric cancer cells via autocrine TGFβ/TGFβR signaling.

Type II, but not type I, cGMP-dependent protein kinase reverses bFGF-induced proliferation and migration of U251 human glioma cells

Previous data have shown that the type II cGMP‑dependent protein kinase (PKG II) inhibits the EGF‑induced MAPK signaling pathway. In order to thoroughly investigate PKG, it is necessary to elucidate the function of another type of PKG, PKG I. The aim of this study was to investigate the possible inhibitory effect of PKG II and PKG I activity on the basic fibroblast growth factor (bFGF)‑induced proliferation and migration of U251 human glioma cells and the possible underlying mechanisms. U251 cells were infected with adenoviral constructs encoding cDNA of PKG I (Ad‑PKG I) or PKG II (Ad‑PKG II) to increase the expression levels of PKG I or PKG II and then treated with 8‑Br‑cGMP and 8‑pCPT‑cGMP, respectively, to activate the enzyme. An MTT assay was used to detect the proliferation of the U251 cells. The migration of the U251 cells was analyzed using a Transwell migration assay. Western blot analysis was used to detect the phosphorylation/activation of the fibroblast growth factor receptor (FGFR), MEK and ERK and the nuclear distribution of p-ERK. The results showed that bFGF treatment increased the proliferation and migration of U251 cells, accompanied by increased phosphorylation of FGFR, MEK and ERK. Furthermore, the nuclear distribution of p-ERK increased following bFGF treatment. Increasing the activity of PKG II through infection with Ad-PKG II and stimulation with 8-pCPT-cGMP significantly attenuated the aforementioned effects of the bFGF treatment, while increased PKG I activity did not inhibit the effects of bFGF treatment. These data suggest that increased PKG II activity attenuates bFGF‑induced proliferation and migration by inhibiting the MAPK/ERK signaling pathway, whereas PKG I does not.

Long pentraxin 3/tumor necrosis factor-stimulated gene-6 interaction: a biological rheostat for fibroblast growth factor 2-mediated angiogenesis

OBJECTIVE

Angiogenesis is regulated by the balance between pro- and antiangiogenic factors and by extracellular matrix protein interactions. Fibroblast growth factor 2 (FGF2) is a major proangiogenic inducer inhibited by the interaction with the soluble pattern recognition receptor long pentraxin 3 (PTX3). PTX3 is locally coexpressed with its ligand tumor necrosis factor-stimulated gene-6 (TSG-6), a secreted glycoprotein that cooperates with PTX3 in extracellular matrix assembly. Here, we characterized the effect of TSG-6 on PTX3/FGF2 interaction and FGF2-mediated angiogenesis.

METHODS AND RESULTS

Solid phase binding and surface plasmon resonance assays show that TSG-6 and FGF2 bind the PTX3 N-terminal domain with similar affinity. Accordingly, TSG-6 prevents FGF2/PTX3 interaction and suppresses the inhibition exerted by PTX3 on heparan sulfate proteoglycan/FGF2/FGF receptor complex formation and on FGF2-dependent angiogenesis in vitro and in vivo. Also, endogenous PTX3 exerts an inhibitory effect on vascularization induced by FGF2 in a murine subcutaneous Matrigel plug assay, the inhibition being abolished in Ptx3-null mice or by TSG-6 treatment in wild-type animals.

CONCLUSION

TSG-6 reverts the inhibitory effects exerted by PTX3 on FGF2-mediated angiogenesis through competition of FGF2/PTX3 interaction. This may provide a novel mechanism to control angiogenesis in those pathological settings characterized by the coexpression of TSG-6 and PTX3, in which the relative levels of these proteins may fine-tune the angiogenic activity of FGF2.

Basic fibroblast growth factor induces cholangiocarcinoma cell migration via activation of the MEK1/2 pathway

The purpose of this study was to investigate the roles played by basic fibroblast growth factor (bFGF) in the induction of cholangiocarcinoma cell progression and to identify the signal transduction molecules that are activated by bFGF in cholangiocarcinoma cells. FGF receptor-2 (FGFR2) was shown to be expressed in two cholangiocarcinoma cell lines (RMCCA1 and KKU-100). Samples from RMCCA1 and KKU-100 were assayed for the mRNA. Phosphorylation levels were determined by Western blotting. Treatment of the cholangiocarcinoma cells with bFGF enhanced signaling via the phosphorylation of MEK1/2, induced cholangiocarcinoma cell migration and resulted in high levels of actin polymerization. Moreover, treatment with a MEK1/2 inhibitor (U0126) attenuated the effect of bFGF-induced cholangiocarcinoma cell migration. Taken together, these observations indicate that bFGF enhances the migration of cholangiocarcinoma cells and that this enhancement is regulated by the phosphorylation of MEK1/2.

Expression of hepatocyte growth factor and its receptor c-Met in human pituitary adenomas

Hepatocyte growth factor (HGF) and its receptor c-Met have been known as key determinants of growth and angiogenesis in some brain tumors like gliomas, meningiomas, and schwannomas. But little is known about their expression in pituitary adenomas. In this study, the expression of HGF and c-Met in pituitary adenomas of different histology types was investigated by immunohistochemistry, and correlative analysis of their expression with microvessel density (MVD), Ki-67 expression, and other clinicopathologic factors was made. The results showed that the expression of HGF and c-Met exists in 98% (64 of 65) and 92% (60 of 65) pituitary adenomas, respectively, and co-expression of them existed in 91% (59 of 65) adenomas. HGF had significant correlation with MVD (Spearman's correlation coefficient, r = .31, P = .01) and Ki-67 (r = .32, P = .01). c-Met had significant correlation with MVD (r = .30, P = .02) and Ki-67 (r = .38, P = .00). HGF and c-Met expression had no significant correlation with age or extrasellar extension. There were no significant differences in HGF and c-Met expression between pituitary adenomas of different histology types. The results indicate that HGF and c-Met are widely expressed in pituitary adenomas, and their expression correlates with MVD and Ki-67 expression.