Fibroblast growth factor receptor 4 promotes progression and correlates to poor prognosis in cholangiocarcinoma

Fibroblast growth factor receptor 4 (FGFR4) is related to poor prognosis of several cancers, but the correlation between FGFR4 expression and cholangiocarcinoma (CCA) has not been well elucidated. We investigated the expression of FGFR4 in 83 intrahepatic cholangiocarcinomas (IHCCs), 75 perihilar cholangiocarcinomas (PHCCs) and 41 distal cholangiocarcinomas (DCCs) by immunohistochemistry (IHC), and subsequently evaluated association of FGFR4 with clinicopathologic parameters and survival rate. The rate of FGFR4 higher expression was 61.4% (51/83) in IHCCs, 53.3% (40/75) in PHCCs and 56.1% (23/41) in DCCs. FGFR4 expression was significantly related to poor prognosis of IHCC (P = 0.002) and PHCC (P = 0.019) with univariate analysis, and also identified as an independent prognostic factor in IHCC (P = 0.045) and PHCC (P = 0.049) with multivariate analysis. Additionally, with functional assays in vitro, we found FGFR4 can induce proliferation, invasion and epithelial–mesenchymal transition (EMT) of CCA cell lines with FGF19 stimulation. Moreover, FGFR4 inhibitor AP24354 can suppress proliferation, invasion and induce apoptosis of CCA cells. In conclusion, FGFR4 expression can be identified as a significant independent prognostic biomarker of IHCC and PHCC. FGFR4 played a pivotal role in proliferation, invasion and EMT of CCA. FGFR4 inhibitor can suppress proliferation, invasion and induce apoptosis of CCA, indicating that FGFR4 may act as a potential therapeutic target.     

Directed evolution to low nanomolar affinity of a tumor-targeting epidermal growth factor receptor-binding affibody molecule

The epidermal growth factor receptor 1 (EGFR) is overexpressed in various malignancies and is associated with a poor patient prognosis. A small, receptor-specific, high-affinity imaging agent would be a useful tool in diagnosing malignant tumors and in deciding upon treatment and assessing the response to treatment. We describe here the affinity maturation procedure for the generation of Affibody molecules binding with high affinity and specificity to EGFR. A library for affinity maturation was constructed by rerandomization of selected positions after the alignment of first-generation binding variants. New binders were selected with phage display technology, using a single oligonucleotide in a single-library effort, and the best second-generation binders had an approximately 30-fold improvement in affinity (K_d = 5-10 nM) for the soluble extracellular domain of EGFR in biospecific interaction analysis using Biacore. The dissociation equilibrium constant, K_d, was also determined for the Affibody with highest affinity using EGFR-expressing A431 cells in flow cytometric analysis (K_d = 2.8 nM). A retained high specificity for EGFR was verified by a dot blot assay showing staining only of EGFR proteins among a panel of serum proteins and other EGFR family member proteins (HER2, HER3, and HER4). The EGFR-binding Affibody molecules were radiolabeled with indium-111, showing specific binding to EGFR-expressing A431 cells and successful targeting of the A431 tumor xenografts with 4-6% injected activity per gram accumulated in the tumor 4 h postinjection.     

Expression and Prognostic Significance of Human Epidermal Growth Factor Receptors 1, 2 and 3 in Periampullary Adenocarcinoma

Periampullary adenocarcinoma, including pancreatic cancer, is a heterogeneous group of tumours with dismal prognosis, for which there is an urgent need to identify novel treatment strategies. The human epithelial growth factor receptors EGFR, HER2 and HER3 have been studied in several tumour types, and HER-targeting drugs have a beneficial effect on survival in selected types of cancer. However, these effects have not been evident in pancreatic cancer, and remain unexplored in other types of periampullary cancer. The prognostic impact of HER-expression in these cancers also remains unclear. The aim of this study was therefore to examine the expression and prognostic value of EGFR, HER2 and HER3 in periampullary cancer, with particular reference to histological subtype. To this end, protein expression of EGFR, HER2 and HER3, and HER2 gene amplification was assessed by immunohistochemistry and silver in situ hybridization, respectively, on tissue microarrays with tumours from 175 periampullary adenocarcinomas, with follow-up data on recurrence-free survival (RFS) and overall survival (OS) for up to 5 years. EGFR expression was similar in pancreatobiliary (PB) and intestinal (I) type tumours, but high HER2 and HER3 expression was significantly more common in I-type tumours. In PB-type cases receiving adjuvant gemcitabine, but not in untreated cases, high EGFR expression was significantly associated with a shorter OS and RFS, with a significant treatment interaction in relation to OS (p_{interaction =} 0.042). In I-type cases, high EGFR expression was associated with a shorter OS and RFS in univariable, but not in multivariable, analysis. High HER3 expression was associated with a prolonged RFS in univariable, but not in multivariable, analysis. Neither HER2 protein expression nor gene amplification was prognostic. The finding of a potential interaction between the expression of EGFR and response to adjuvant chemotherapy in PB-type tumours needs validation, and merits further study.     

Overexpression of PDGFA and its receptor during carcinogenesis of Opisthorchis viverrini-associated cholangiocarcinoma

Cholangiocarcinoma (CCA) is a crucial health problem in northeastern part of Thailand, which is caused by a combination of Opisthorchis viverrini infection and nitrosamine. A better understanding of its molecular mechanism is an important step to discover and develop the new diagnostics and therapies for CCA. To reveal the involvement of potential genes in the development of CCA, the present study investigated the expression kinetics of platelet-derived growth factor alpha (Pdgfa) and its receptor (Pdgfra) during the tumorigenesis of CCA induced by O. viverrini infection with quantitative RT-PCR, and confirmed the expression with immunohistological staining. The results showed that in the hamster model of opisthorchiasis-associated CCA, the expression of Pdgfa was increased after infection plus N-nitrosodimethylamine (NDMA) administration, reached its peak at 2 months post infection, and remained at the high level until 6 months. Similarly, the expression of Pdgfra was increased time-dependently. The positive immunostaining for PDGFA proteins was observed in the cytoplasm of epithelial tumor cells of hamster CCA. Moreover, the analysis of the expression of these genes in 10 cases of human opisthorchiasis-associated CCA showed that Pdgfa was overexpressed in 80%, and Pdgfra was overexpressed in 40% cases (> 3.0 folds, compared with the expressions of adjacent normal tissues). This result suggests that PDGFA is likely involved in the tumorigenesis of opisthorchiasis-associated CCA, and may be a promising candidate biomarker for diagnosis and treatment strategies of CCA.     

Role of EGFR SNPs in survival of advanced lung adenocarcinoma patients treated with Gefitinib

Aim

As a novel molecularly targeting agent for non-small-cell lung cancer (NSCLC), Gefitinib can block its tyrosine kinase activity of the epidermal growth factor receptor (EGFR). Genetic variations in EGFR may affect its protein function or expression and lead to diverse outcomes in NSCLC patients after Gefitinib therapy. Therefore, this prospective study examined whether EGFR single nucleotide polymorphisms (SNPs) are associated with different survival time in advanced lung adenocarcinoma patients treated with Gefitinib.

Methods

One hundred and twenty-eight patients with stage IIIB or IV lung adenocarcinoma receiving Gefitinib target therapy between 2008 and 2010 were recruited in this study. Six EGFR haplotype-tagging SNPs were genotyped by the Sequenom MassArray system. Survival by different genotypes was compared using Kaplan–Meier methods. Cox proportional hazards models were applied to estimate the effect of prognostic factors on overall survival (OS) and progression-free survival (PFS).

Results

After the median 16.6 months of follow-up, the unfavorable EGFR rs2293347AA or GA genotype was significantly correlated with shorter OS (AA vs. GG: 2.0 vs. 21.0 months; hazard ratio (HR) = 2.44, 95% confidence interval (CI) = 1.06–5.56; P = 0.036; GA vs. GG: 15.0 vs. 21.0 months; HR = 1.75, 95%CI = 1.08–2.86, P = 0.025) compared with the favorable rs2293347GG genotype. The prognostic significance of EGFR rs4947492 polymorphism on OS also existed (GG carriers vs. AA carriers: median OS = 24.6 vs. 14.9 months, HR = 0.29, 95%CI = 0.10–0.83, P = 0.021). No significant associations were found among other EGFR SNPs and survival.

Conclusion

EGFR rs2293347 and rs4947492 SNPs might be potential predictive markers of OS in advanced lung adenocarcinoma patients treated with Gefitinib.     

miR-221 Promotes Epithelial-Mesenchymal Transition through Targeting PTEN and Forms a Positive Feedback Loop with β-catenin/c-Jun Signaling Pathway in Extra-Hepatic Cholangiocarcinoma

Extrahepatic cholangiocarcinoma (EHCC) is a refractory malignancy with poor prognosis due to its early invasion, metastasis and recurrence after operation. Therefore, understanding the mechanisms of invasion and metastasis is the key to the development of new and effective therapeutic strategies for EHCC. In the present study we demonstrated that miR-221 promoted EHCC invasion and metastasis through targeting PTEN and formed a positive feedback loop with β-catenin/c-Jun signaling pathway. We found miR-221 was upregulated in EHCC specimens and CC cell lines. Moreover, miR-221 was found strongly associated with the metastasis and prognosis of EHCC patients. The expression of PTEN was downregulated in EHCC patients and CC cell lines, and was further demonstrated as one of the downstream targets of miR-221. In addition, our data indicated that β-catenin activated miR-221 through c-jun, while miR-221 enhanced β-catenin signaling induced-epithelial-mesenchymal transition (EMT) by targeting PTEN, hence forming a positive feedback loop in EHCC cell lines. In conclusion, our results suggested that miR-221 promotes EMT through targeting PTEN and forms a positive feedback loop with β-catenin/c-Jun signaling pathway in EHCC.     

Expression and significance of SOX B1 genes in glioblastoma multiforme patients

The overall survival of glioblastoma multiforme (GBM) patients remains poor. To improve patient outcomes, effective diagnostic and prognostic biomarkers for GBM are needed. In this study, we first applied bioinformatic analyses to identify biomarkers for GBM, focusing on SOX (sex‐determining region on the Y chromosome (SRY)‐related high mobility group (HMG) box) B1 family members. The ONCOMINE, GEPIA, LinkedOmics and CCLE databases were used to assess mRNA expression levels of the SOX B1 family members in different cancers and normal tissue. Further bioinformatic analysis was performed using the ONCOMINE database in combination with the LinkedOmics data set to identify the prognostic value of SOX B1 family members for GBM. We found mRNA expression levels of all tested SOX B1 genes were significantly increased in GBM. In the LinkedOmics database, increased expression of SOX3 indicated a better overall survival. In GEPIA databases, increased expression of all SOX B1 family members suggested an improved overall survival, but none of them were statistically different. Then, Transwell assays and wound healing were employed to evaluate the motility and invasive captivity of U251 cells when silencing SOX2 and SOX3. We found exogenous inhibition of SOX2 appeared to reduce the migration and invasion of U251 cells in vitro. Collectively, our research suggested that SOX2 might serve as a cancer‐promoting gene to identify high‐risk GBM patients, and SOX3 had the potential to be a prognostic biomarker for GBM patients.     

EGFR overexpression relates to triple negative profile and poor prognosis in breast cancer patients in Tunisia

Background: The prognosis of breast carcinoma is related to a large variety of clinical and pathological factors. Currently, only oestrogen (ER) and progesterone (PR) receptors and human epidermal growth factor receptor 2 (HER2) are used in routine pathological assessment as biomarkers. The aim of this study was to evaluate the prognostic impact of epidermal growth factor receptor (EGFR) expression individually and in combination to classical biomarkers (HER2, ER, and PR), and its relation to tumors with triple negative profile in Tunisian breast carcinoma.

Methods: Immunohistochemistry was used to estimate the rate expression of these receptors. Univariate and multivariate analyses were used to explore the prognostic significance of EGFR in this study.

Results: The expression rate of EGFR was 28.6%. EGFR expression was inversely correlated to that of ER (P < 0.001). Significant correlations between the expression of EGFR and the high histological Scarff-Bloom-Richardson (SBR) grade (P = 0.038) and also with tumors size (P = 0.041) were observed. The triple negative profile (TN: ER?/PR?/HER2?) was present in 17.3% of cases. EGFR overexpression was positively associated with this clinical aggressive profile (P < 0.001). Survival analysis showed that EGFR expression was associated with poor survival of patients (P = 0.004). In multivariate analysis, EGFR expression (P = 0.035) was found to be independent prognostic factors (significantly correlated to survival).

Conclusion: EGFR overexpression was observed in 28.6% of Tunisian breast carcinoma, associated with unfavorable prognosis and with triple negative tumors. Systemically evaluation of EGFR in breast carcinoma could benefit especially to TN subgroup from EGFR targeting agents.     

Inverse Regulation of EGFR/HER1 and HER2-4 in Normal and Malignant Human Breast Tissue

Cross-talk between the estrogen and the EGFR/HER signalling pathways has been suggested as a potential cause of resistance to endocrine therapy in breast cancer. Here, we determined HER1-4 receptor and neuregulin-1 (NRG1) ligand mRNA expression levels in breast cancers and corresponding normal breast tissue from patients previously characterized for plasma and tissue estrogen levels. In tumours from postmenopausal women harbouring normal HER2 gene copy numbers, we found HER2 and HER4, but HER3 levels in particular, to be elevated (2.48, 1.30 and 22.27 –fold respectively; P<0.01 for each) compared to normal tissue. Interestingly, HER3 as well as HER4 were higher among ER+ as compared to ER- tumours (P=0.004 and P=0.024, respectively). HER2 and HER3 expression levels correlated positively with ER mRNA (ESR1) expression levels (r=0.525, P=0.044; r=0.707, P=0.003, respectively). In contrast, EGFR/HER1 was downregulated in tumour compared to normal tissue (0.13-fold, P<0.001). In addition, EGFR/HER1 correlated negatively to intra-tumour (r=-0.633, P=0.001) as well as normal tissue (r=-0.556, P=0.006) and plasma estradiol levels (r=-0.625, P=0.002), suggesting an inverse regulation between estradiol and EGFR/HER1 levels. In ER+ tumours from postmenopausal women, NRG1 levels correlated positively with EGFR/HER1 (r=0.606, P=0.002) and negatively to ESR1 (r=-0.769, P=0.003) and E2 levels (r=-0.542, P=0.020). Our results indicate influence of estradiol on the expression of multiple components of the HER system in tumours not amplified for HER2, adding further support to the hypothesis that cross-talk between these systems may be of importance to breast cancer growth in vivo.     

Coexpression of EGFR and CXCR4 Predicts Poor Prognosis in Resected Pancreatic Ductal Adenocarcinoma

BackgroundEpidermal growth factor receptor (EGFR) is highly expressed in pancreatic ductal adenocarcinoma (PDAC) and is involved in tumorigenesis and development. However, EGFR expression alone has limited clinical and prognostic significance. Recently, the cross-talk between EGFR and G-protein-coupled chemokine receptor CXCR4 has become increasingly recognized.MethodsIn the present study, immunohistochemical staining of EGFR and CXCR4 was performed on paraffin-embedded specimens from 131 patients with surgically resected PDAC. Subsequently, the associations between EGFR expression, CXCR4 expression, EGFR/CXCR4 coexpression and clinicopathologic factors were assessed, and survival analyses were performed.ResultsIn total, 64 (48.9%) patients expressed EGFR, 68 (51.9%) expressed CXCR4, and 33 (25.2%) coexpressed EGFR and CXCR4. No significant association between EGFR and CXCR4 expression was observed (P = 0.938). EGFR expression significantly correlated with tumor differentiation (P = 0.031), whereas CXCR4 expression significantly correlated with lymph node metastasis (P = 0.001). EGFR/CXCR4 coexpression was significantly associated with lymph node metastasis (P = 0.026), TNM stage (P = 0.048), and poor tumor differentiation (P = 0.004). By univariate survival analysis, both CXCR4 expression and EGFR/CXCR4 coexpression were significant prognostic factors for poor disease-free survival (DFS) and overall survival (OS). Moreover, EGFR/CXCR4 coexpression significantly increased the hazard ratio for both recurrence and death compared with EGFR or CXCR4 protein expression alone. Multivariate survival analysis demonstrated that EGFR/CXCR4 coexpression was an independent prognostic factor for DFS (HR = 2.33, P<0.001) and OS (HR = 2.48, P = 0.001).ConclusionsIn conclusion, our data indicate that although EGFR expression alone has limited clinical and prognostic significance, EGFR/CXCR4 coexpression identified a subset of PDAC patients with more aggressive tumor characteristics and a significantly worse prognosis. Our results suggest a potentially important "cross-talk" between CXCR4 and EGFR intracellular pathways and indicate that the simultaneous inhibition of these pathways might be an attractive therapeutic strategy for PDAC.     

Hepatic cytochrome P450 2A6 and 2E1 status in peri-tumor tissues of patients with Opisthorchis viverrini-associated cholangiocarcinoma

Endogenous nitrosation due to chronic inflammation is enhanced in opisthorchiasis and plays a crucial role in the development of cholangiocarcinoma (CCA). Hepatic cytochrome P450 (CYP) family enzymes, especially CYP2A6 and CYP2E1, are involved in the metabolism of procarcinogens; these two enzymes metabolize endogenous nitrosamines to carcinogenic N-dimethylnitrosamine (NDMA). CYP2A6 activity is increased in patients infected with Opisthorchis viverrini. Our aim was to determine whether the expression and function of CYP2A6 and 2E1 in the livers of patients with O. viverrini-associated cholangiocarcinoma (CCA) was altered compared to livers without CCA. Livers of CCA patients (n = 13 cases) showed increased enzyme activities, protein and mRNA levels of CYP2A6 whereas the enzyme activity and protein levels of CYP2E1 were markedly decreased (P < 0.05). CYP2E1 mRNA levels were not altered. Large numbers of inflammatory cells and increased iNOS expression was found in areas adjacent to the tumor. The data provide evidence to support the concept that enhanced CYP2A6 activity and diminished CYP2E1 activity probably involve to the progression of CCA.     

Expression and Prognostic Significance of Human Epidermal Growth Factor Receptors 1 and 3 in Gastric and Esophageal Adenocarcinoma

Background

Gastric and esophageal adenocarcinomas are major global cancer burdens. These cancer forms are characterized by a poor prognosis and a modest response to chemo- radio- and targeted treatment. Hence there is an obvious need for further enhanced diagnostic and treatment strategies. The aim of this study was to examine the expression and prognostic impact of human epidermal growth factor receptor 1 (HER1/EGFR) and 3 (HER3), as well as the occurrence of EGFR and KRAS mutations in gastric and esophageal adenocarcinoma.

Methods

Immunohistochemical expression of EGFR and HER3 was analysed in all primary tumours and a subset of lymph node metastases in a consecutive cohort of 174 patients with adenocarcinoma of the stomach, cardia and esophagus. The anti-HER3 antibody used was validated by siRNA-mediated knockdown, immunohistochemistry and quantitative real-time PCR. EGFR and KRAS mutation status was analysed by pyrosequencing tecchnology.

Results and Discussion

High EGFR expression was an independent risk factor for shorter overall survival (OS), whereas high HER3 expression was associated with a borderline significant trend towards a longer OS. KRAS mutations were present in only 4% of the tumours and had no prognostic impact. All tumours were EGFR wild-type. These findings contribute to the ongoing efforts to decide on the potential clinical value of different HERs and druggable mutations in gastric and esophageal adenocarcinomas, and attention is drawn to the need for more standardised investigational methods.     

The Association between EGFR and cMET Expression and Phosphorylation and Its Prognostic Implication in Patients with Breast Cancer

EGFR and cMET cross-talk is involved in breast cancer (BC) progression and resistance to different targeted therapies, however little is known about the co-expression patterns of EGFR and cMET or its prognostic significance in BC. Protein levels of EGFR, cMET and their phosphorylated proteins were measured in 825 BC samples using reverse phase protein array (RPPA). Given unimodal distribution of proteins, the median was selected as a cut-off after sensitivity analyses. Kaplan-Meier survival curves were used to estimate relapse-free (RFS) and overall survival (OS). Cox-proportional hazards models were utilized to determine associations between EGFR and cMET with outcomes. Mean age was 58 years with 457 (55%) hormone receptor (HR) positive, 211 (26%) triple-negative (TN) and 148 (18%) HER2 positive tumors (HER2+). HER2+ was associated with higher EGFR expression and phosphorylation, compared to HR and TN (p<0.05). High EGFR expression was associated with higher phosphorylated-cMET (p-cMET) but not cMET (ANOVA p-cMET p < 0.001; cMET p = 0.34). The same association was found with high phosphorylated-EGFR (p-EGFR) group at Tyr992 and Tyr1068 (both p < 0.001). High expressions in either of two p-EGFRs were linked with higher cMET as well (all p<0.001). For the TN subtype, high expression in EGFR and p-EGFR at Tyr992 but not at Tyr1068 was associated with higher p-cMET (p<0.00, p = 0.012, p = 0.4 respectively). Only high expression in p-EGFR at Tyr992 was linked with higher expression of cMET (p = 0.02). In contrast, among HER2 subtype, high expression in p-EGFR at Tyr1068 but not at Tyr992 was associated with higher cMET and p-cMET (cMET p = 0.023;p-cMET p<0.001). Four subgroups of patients defined by dichotomized EGFR/p-EGFR and cMET/p-cMET level demonstrated no significant differences in survival. In multivariate analyses, neither cMET nor EGFR expression/activation was found to be an independent prognostic factor in survival outcome.     

Characterization of a natural inducer of coral larval metamorphosis

External chemical signals used by scleractinian corals to recognize suitable substrata for larval settlement and metamorphosis were identified from crustose coralline red algae (CCA). A fragment of coral rubble with CCA induced larval metamorphosis of the scleractinian coral Pseudosiderastrea tayamai. A natural inducer and compounds that enhanced its effect in larval metamorphosis were isolated from the methanol extracts of coral rubble with CCA. A bromotyrosine derivative, 11-deoxyfistularin-3 (10^− 7 M) isolated from the CCA, induced the metamorphosis of P. tayamai larvae (27.5 ± 24.0%). In the presence of fucoxanthinol (10^− 9 M) and fucoxanthin (10^− 9 M), the percentage of metamorphosis induced by the bromotyrosine derivative was further enhanced to 87.8 ± 13.0 and 88.4 ± 17.8%, respectively. Both carotenoids are also found in the coral rubble with CCA. These results suggest that bromotyrosine derivative and carotenoids have a synergistic effect in the metamorphosis of P. tayamai larvae. The synergistic effect provides a higher selectivity for recruitment than a single-component natural inducer for recognizing suitable substrata for larval metamorphosis. Thus, the effect might offer a survival advantage for benthic marine invertebrates.     

The Prognostic Value of SOX2 Expression in Non-Small Cell Lung Cancer: A Meta-Analysis

Objective

To investigate the association of SOX2 expression in tumor with clinicopathological features and survival of non-small-cell lung carcinoma (NSCLC) patients.

Methods

Publications assessing the clinicopathological characteristics and prognostic significance of SOX2 in NSCLC were identified up to May 2013. A meta-analysis of eligible studies was performed using standard statistical methods to clarify the association between SOX2 expression and these clinical parameters.

Results

A total of eight studies met the inclusion criteria. Analysis of these data showed that SOX2 expression was positively associated with squamous histology, (pooled OR = 5.26, 95% CI: 1.08–25.6, P = 0.040). Simultaneously, we also found that SOX2 expression was positively associated with overall survival (pooled HR = 0.65, 95% CI: 0.47–0.89, P = 0.007, random-effect).

Conclusions

SOX2 expression in tumor is a candidate positive prognostic biomarker for NSCLC patients.