Dovitinib preferentially targets endothelial cells rather than cancer cells for the inhibition of hepatocellular carcinoma growth and metastasis

MEX3A determines in vivo hepatocellular carcinoma progression and induces resistance to sorafenib in a Hippo-dependent way

BACKGROUND

Hepatocellular carcinoma (HCC) is most common malignant tumor worldwide, and one of the most lethal malignancies. MEX3A, RNA-binding protein, is profoundly implicated in tumor initiation and progression. But its role and potential mechanism in HCC remains fully unclear.

METHODS

The expression of MEX3A in HCC was analysis using the data derived from the Cancer Genome Atlas (TCGA) dataset and further confirmed by HCC samples and cells lines. The roles of MEX3A in the proliferation, migration and sorafenib resistance were detected both in vitro and vivo. In addition, the underline mechanism was investigated.

RESULTS

In this study, MEX3A expression was upregulated in HCC tissue and cell lines. Knockdown or overexpression of MEX3A disturbed the proliferation, migration and apoptosis of HCC cells by modulating the activation of Hippo signaling pathway. The expression of MEX3A was negatively associated with sorafenib sensitivity and upregulated in sorafenib resistant HCC cells. MEX3A knockdown facilitated the expression of WWC1, a negative modulator of Hippo signaling pathway, and led to increase of the phosphorylation of LATS1 and YAP1. Pharmacological inhibition of LATS1 or WWC1 overexpression alleviated the proliferative and migrated suppression and increased sorafenib sensitivity, whereas WWC1 inhibition using genetic interference strategy showed opposite trend in MEX3A knockdown HCC cells. Importantly, MEX3A knockdown led to growth and lung metastasis inhibition using xenograft model established by means of subcutaneous or tail vein injection. In addition, a combination of MEX3A knockdown and WWC1 overexpression dramatically enhances the growth inhibition of sorafenib in vivo.

CONCLUSION

MEX3A may facilitate HCC progression and hinder sorafenib sensitivity via inactivating Hippo signaling. The present study suggested that targeting MEX3A can be served as a novel therapeutic strategy for HCC.

Bioinformatics Analysis Combined With Experiments Predicts PUDP as a Potential Prognostic Biomarker for Hepatocellular Carcinoma Through Its Interaction With Tumor Microenvironment

Hepatocellular carcinoma (HCC) is one of the deadliest tumors in the world and is notorious for poor prognosis. There is mounting evidence that pseudouridine performs key functions in the initiation and progression of several cancers. A previous study demonstrated that Pseudouridine 5’-phosphatase (PUDP) may be a novel prognostic biomarker in colorectal cancer. However, in the past, we have paid little attention to PUDP and we are still not clear about its function and role in cancer. In this study, a pan-cancer analysis of PUDP expression and prognosis was performed firstly using The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) data and we found that PUDP may be a potential oncogene for HCC. Then the most potential upstream microRNA contributing to PUDP was identified as let-7c-5p through expression analysis, correlation analysis, and survival analysis. Subsequently, the result of single cell RNA sequencing (scRNA-seq) demonstrated that PUDP was significantly highly expressed on malignant cells. In addition, there are significantly positive correlations between PUDP and tumor immune cell infiltration, biomarkers of immune cells, and immune checkpoint expression, especially with tumor-promoting immune cells such as T cell regulatory (Treg), Myeloid-derived suppressor cell (MDSC), cancer-associated fibroblast (CAF). Moreover, we found the methylation level of three loci was positively correlated with PUDP expression and four loci were negatively correlated. 15 pairs of HCC and normal adjacent tissues from HCC patients who were treated at our center were used to verify the results of the bioinformatics analysis and the results of experiments are similar to the bioinformatics analysis. Our study demonstrated that HCC patients with high PUDP expression are less likely to benefit from immunotherapy, and in addition, we explored the relationship between PUDP and anticancer drugs. Finally, we explored the clinical relevance of PUDP, identified PUDP as an independent risk factor for HCC patients and constructed a prognostic model, used International Cancer Genome Consortium (ICGC) data to do external validation. Collectively, our study demonstrated that high expression of PUDP suggested a poor prognosis and low response to immunotherapy, providing new insight into the treatment and prognosis of HCC.

Targeting Drugs Against Fibroblast Growth Factor(s)-Induced Cell Signaling

BACKGROUND

The fibroblast growth factor (FGF) family is comprised of 23 highly regulated monomeric proteins that regulate a plethora of developmental and pathophysiological processes, including tissue repair, wound healing, angiogenesis, and embryonic development. Binding of FGF to fibroblast growth factor receptor (FGFR), a tyrosine kinase receptor, is facilitated by a glycosaminoglycan, heparin. Activated FGFRs phosphorylate the tyrosine kinase residues that mediate induction of downstream signaling pathways, such as RAS-MAPK, PI3K-AKT, PLCγ, and STAT. Dysregulation of the FGF/FGFR signaling occurs frequently in cancer due to gene amplification, FGF activating mutations, chromosomal rearrangements, integration, and oncogenic fusions. Aberrant FGFR signaling also affects organogenesis, embryonic development, tissue homeostasis, and has been associated with cell proliferation, angiogenesis, cancer, and other pathophysiological changes.

OBJECTIVE

This comprehensive review will discuss the biology, chemistry, and functions of FGFs, and its current applications toward wound healing, diabetes, repair and regeneration of tissues, and fatty liver diseases. In addition, specific aberrations in FGFR signaling and drugs that target FGFR and aid in mitigating various disorders, such as cancer, are also discussed in detail.

CONCLUSION

Inhibitors of FGFR signaling are promising drugs in the treatment of several types of cancers. The clinical benefits of FGF/FGFR targeting therapies are impeded due to the activation of other RTK signaling mechanisms or due to the mutations that abolish the drug inhibitory activity on FGFR. Thus, the development of drugs with a different mechanism of action for FGF/FGFR targeting therapies is the recent focus of several preclinical and clinical studies.

A Selective FGFR inhibitor AZD4547 suppresses RANKL/M-CSF/OPG-dependent ostoclastogenesis and breast cancer growth in the metastatic bone microenvironment

Aberrant activation of fibroblast growth factor receptor (FGFR) signalling contributes to progression and metastasis of many types of cancers including breast cancer. Accordingly, FGFR targeted tyrosine kinase inhibitors (TKIs) are currently under development. However, the efficacy of FGFR TKIs in the bone microenvironment where breast cancer cells most frequently metastasize and also where FGFR is biologically active, has not been clearly investigated. We investigated the FGFR-mediated interactions among cancer and the bone microenvironment stromal cells (osteoblasts and osteoclasts), and also the effects of FGFR inhibition in bone metastasis. We showed that addition of culture supernatant from the MDA-MB-134-VI FGFR-amplified breast cancer cells-activated FGFR siganalling in osteoblasts, including increased expression of RANKL, M-CSF, and osteoprotegerin (OPG). Further in vitro analyses showed that AZD4547, an FGFR TKI currently in clinical trials for breast cancer, decreased RANKL and M-CSF, and subsequently RANKL and M-CSF-dependent osteoclastogenesis of murine bone marrow monocytes. Moreover, AZD4547 suppressed osteoclastogenesis and tumor-induced osteolysis in an orthotopic breast cancer bone metastasis mouse model using FGFR non-amplified MDA-MB-231 cells. Collectively, our results support that FGFR inhibitors inhibit the bone microenvironment stromal cells including osteoblasts and osteoclasts, and effectively suppress both tumor and stromal compartments of bone metastasis.

A splicing switch from ketohexokinase-C to ketohexokinase-A drives hepatocellular carcinoma formation

Dietary fructose is primarily metabolized in the liver. Here we demonstrate that, compared with normal hepatocytes, hepatocellular carcinoma (HCC) cells markedly reduce the rate of fructose metabolism and the level of reactive oxygen species, as a result of a c-Myc-dependent and heterogeneous nuclear ribonucleoprotein (hnRNP) H1- and H2-mediated switch from expression of the high-activity fructokinase (KHK)-C to the low-activity KHK-A isoform. Importantly, KHK-A acts as a protein kinase, phosphorylating and activating phosphoribosyl pyrophosphate synthetase 1 (PRPS1) to promote pentose phosphate pathway-dependent de novo nucleic acid synthesis and HCC formation. Furthermore, c-Myc, hnRNPH1/2 and KHK-A expression levels and PRPS1 Thr225 phosphorylation levels correlate with each other in HCC specimens and are associated with poor prognosis for HCC. These findings reveal a pivotal mechanism underlying the distinct fructose metabolism between HCC cells and normal hepatocytes and highlight the instrumental role of KHK-A protein kinase activity in promoting de novo nucleic acid synthesis and HCC development.

Monitoring vascular normalization induced by antiangiogenic treatment with (18)F-fluoromisonidazole-PET

Background: Rationalization of antiangiogenics requires biomarkers. Vascular re‐normalization is one widely accepted mechanism of action for this drug class. The interstitium of tumors with abnormal vasculature is hypoxic. We sought to track vascular normalization with 18F‐misonidazole ([18F]‐FMISO, a probe that detects hypoxia) PET, in response to window‐of‐opportunity (WoO) treatment with the antiangiogenic dovitinib.

Methods: Two patient‐derived pancreas xenografts (PDXs; Panc215 and Panc286) and the spontaneous breast cancer model MMTV‐PyMT were used. Animals were treated during 1 week of WoO treatment with vehicle or dovitinib, preceded and followed by [18F]‐FMISO‐PET, [18F]‐FDG‐PET, and histologic assessment (dextran extravasation, hypoxia and microvessel staining, and necrosis, cleaved caspase‐3 and Ki67 measurements). After WoO treatment, gemcitabine (pancreas)/adriamycin (breast) or vehicle was added and animals were treated until the humane endpoint. Tumor growth inhibition (TGI) and survival were the parameters studied.

Results: [18F]‐FMISO SUV did not change after dovitinib‐WoO treatment compared to vehicle‐WoO (0.54 vs. 0.6) treatment in Panc215, but it decreased significantly in Panc286 (0.58 vs. 1.18; P < 0.05). In parallel, 10‐KDa perivascular dextran extravasation was not reduced with dovitinib or vehicle‐WoO treatment in Panc215, but it was reduced in Panc286. Whereas the addition of dovitinib to gemcitabine was indifferent in Panc215, it increased TGI in Panc286 (TGI switched from −59% to +49%). [18F]‐FMISO SUV changes were accompanied by an almost 100% increase in interstitial gemcitabine delivery (665–1260 ng/mL). The results were validated in the PyMT model.

Conclusions: [18F]‐FMISO accurately monitored vascular re‐normalization and improved interstitial chemotherapy delivery.

We describe a new technique to monitor the efficacy of antiangiogenics.

This drug class currently lacks biomarkers.

Antiangiogenics exert their positive effect by inducing stromal normalization.

18F‐fluoromisonidazole PET is able to monitor stromal normalization.

Tumors showing stromal normalization by PET experience benefit from antiangiogenics.

Adenoid cystic carcinoma: current therapy and potential therapeutic advances based on genomic profiling

Adenoid cystic carcinoma (ACC) is a rare cancer with high potential for recurrence and metastasis. Efficacy of current treatment options, particularly for advanced disease, is very limited. Recent whole genome and exome sequencing has dramatically improved our understanding of ACC pathogenesis. A balanced translocation resulting in the MYB-NFIB fusion gene appears to be a fundamental signature of ACC. In addition, sequencing has identified a number of other driver genes mutated in downstream pathways common to other well-studied cancers. Overexpression of oncogenic proteins involved in cell growth, adhesion, cell cycle regulation, and angiogenesis are also present in ACC. Collectively, studies have identified genes and proteins for targeted, mechanism-based, therapies based on tumor phenotypes, as opposed to nonspecific cytotoxic agents. In addition, although few studies in ACC currently exist, immunotherapy may also hold promise. Better genetic understanding will enable treatment with novel targeted agents and initial exploration of immune-based therapies with the goal of improving outcomes for patients with ACC.

Lenvatinib, everolimus, and the combination in patients with metastatic renal cell carcinoma: a randomised, phase 2, open-label, multicentre trial

BACKGROUND

Currently, metastatic renal cell carcinoma is treated with sequential single agents targeting VEGF or mTOR. Here, we aimed to assess lenvatinib, everolimus, or their combination as second-line treatment in patients with metastatic renal cell carcinoma.

METHODS

We did a randomised, phase 2, open-label, multicentre trial at 37 centres in five countries and enrolled patients with advanced or metastatic, clear-cell, renal cell carcinoma. We included patients who had received treatment with a VEGF-targeted therapy and progressed on or within 9 months of stopping that agent. Patients were randomised via an interactive voice response system in a 1:1:1 ratio to either lenvatinib (24 mg/day), everolimus (10 mg/day), or lenvatinib plus everolimus (18 mg/day and 5 mg/day, respectively) administered orally in continuous 28-day cycles until disease progression or unacceptable toxic effects. The randomisation procedure dynamically minimised imbalances between treatment groups for the stratification factors haemoglobin and corrected serum calcium. The primary objective was progression-free survival in the intention-to-treat population. This study is closed to enrolment but patients' treatment and follow-up is ongoing. This study is registered with ClinicalTrials.gov, number NCT01136733.

FINDINGS

Between March 16, 2012, and June 19, 2013, 153 patients were randomly allocated to receive either the combination of lenvatinib plus everolimus (n=51), single-agent lenvatinib (n=52), or single-agent everolimus (n=50). Lenvatinib plus everolimus significantly prolonged progression-free survival compared with everolimus alone (median 14·6 months [95% CI 5·9-20·1] vs 5·5 months [3·5-7·1]; hazard ratio [HR] 0·40, 95% CI 0·24-0·68; p=0·0005), but not compared with lenvatinib alone (7·4 months [95% CI 5·6-10·2]; HR 0·66, 95% CI 0·30-1·10; p=0·12). Single-agent lenvatinib significantly prolonged progression-free survival compared with everolimus alone (HR 0·61, 95% CI 0·38-0·98; p=0·048). Grade 3 and 4 events occurred in fewer patients allocated single-agent everolimus (25 [50%]) compared with those assigned lenvatinib alone (41 [79%]) or lenvatinib plus everolimus (36 [71%]). The most common grade 3 or 4 treatment-emergent adverse event in patients allocated lenvatinib plus everolimus was diarrhoea (ten [20%]), in those assigned single-agent lenvatinib it was proteinuria (ten [19%]), and in those assigned single-agent everolimus it was anaemia (six [12%]). Two deaths were deemed related to study drug, one cerebral haemorrhage in the lenvatinib plus everolimus group and one myocardial infarction with single-agent lenvatinib.

INTERPRETATION

Lenvatinib plus everolimus and lenvatinib alone resulted in a progression-free survival benefit for patients with metastatic renal cell carcinoma who have progressed after one previous VEGF-targeted therapy. Further study of lenvatinib is warranted in patients with metastatic renal cell carcinoma.

FUNDING

Eisai Inc.

Approaches targeting the FGF-FGFR system: a review of the recent patent literature and associated advanced therapeutic agents

Fibroblast growth factor receptors (FGFRs) and associated ligands (FGFs) are a family of well-validated targets for therapeutic interventions notably in cancer diseases in relation to their prominent roles in cell growth, survival, differentiation and angiogenesis. This patent review encompasses all different approaches (modulators of FGF or FGFR expression, anti-FGF antibodies, anti-FGFR antibodies, FGF traps, tyrosine-kinase (TK) inhibitors, allosteric modulators) used to block completely or partially the activities of the FGF-FGFR complexes resulting in clinical drug candidates or tool agents. Comparative analysis of biochemical, pharmacological or clinical data will be discussed for each class of molecules together with some perspectives.

Dovitinib (CHIR258, TKI258): structure, development and preclinical and clinical activity

Dovitinib is an oral multikinase inhibitor targeting FGF receptors, PDGF receptors and VEGF receptors. Its activity against FGF receptors suggests its usefulness in treating cancers after the failure of VEGF/VEGF receptor-targeting agents. The identified dose and schedule to be used in further studies was 500 mg orally for 5 days on and 2 days off. Biological considerations and the results achieved in a Phase I/II trial suggested its activity in advanced renal cell carcinoma patients pretreated with a tyrosine kinase inhibitor and an mTOR inhibitor. Surprisingly, in a randomized controlled Phase III trial versus sorafenib in the same setting, dovitinib failed to demonstrate any superiority. At present, dovitinib is being tested in different tumor types. However, molecular-based patient selection seems to be key to fully exploit the activity of this drug.

Predicting responsiveness to sorafenib: can the determination of FGF3/FGF4 amplifications enrich for clinical benefit?

A small proportion of patients with advanced hepatocellular carcinoma harbor FGF3/4 gene amplifications in an 11q13 amplicon. A recent report suggests that the presence of this alteration might enrich for sensitivity to sorafenib. Further, there is growing evidence that interference with the FGF/FGFR axis has therapeutic potential in patients with advanced hepatocellular carcinoma.

A prognostic classifier consisting of 17 circulating cytokines is a novel predictor of overall survival for metastatic colorectal cancer patients

We aimed to determine the prognostic values of 39 circulating cytokines in Chinese patients with metastatic colorectal cancer (CRC) and to develop a novel cytokine-based prognostic classifier (CBPC) for prognostic prediction. A total of 176 patients were divided into two cohorts based on the date of first-line chemotherapy. The first 99 cases were assigned to the training cohort, and the remaining 77 cases were assigned to the validation cohort. Thirty-nine cytokines were simultaneously analyzed in the patient serum samples using multiplex bead-based Luminex technology. We used support vector machine-based methods and Cox proportional hazards models to develop a CBPC from the training cohort, which we then validated using the second patient cohort. Univariate analysis showed that FGF-2, TGFα, Flt-3L, GM-CSF, INFα2, GRO, IL-10, MCP-3, MDC, sIL-2Rα, IL-2, IL-7, IL-8, MCP-1, MIP-1β, TNFα and VEGF were significant risk factors affecting the overall survival (OS) of both the training cohort and the validation cohort. We developed a CBPC to predict the OS of metastatic CRC patients using these 17 cytokines (sensitivity, 0.835; specificity, 0.800). In the validation cohort, the CBPC was found to have significant power in predicting the OS of metastatic CRC patients. Our study showed that there were significant associations between cytokine expression and prognosis of the patients with metastatic CRC. The CBPC that we developed includes multiple circulating cytokines and may serve as a novel screening tool for identifying metastatic CRC patients with a high risk of short OS. These high-risk individuals may also be suitable for cytokine-targeted therapies.

Using multiple cytokines to predict hepatocellular carcinoma recurrence in two patient cohorts

BACKGROUND

Cytokines are tightly linked to the carcinogenesis, development and prognosis of hepatocellular carcinoma (HCC). We determined the prognostic value of 39 circulating cytokines in HCC patients after radical resection and then developed a novel cytokine-based prognostic classifier (CBPC) for the prediction of patient prognosis.

METHODS

A total of 179 patients were divided into two cohorts based on the date of radical resection. Thirty-nine cytokines were simultaneously analysed in patient serum samples using multiplex bead-based Luminex technology. Support vector machine-based methods and Cox proportional hazard models were used to develop a CBPC from the training cohort, which was then validated in the validation cohort.

RESULTS

Among seven cytokines significantly correlating with the disease-free survival (DFS) in the training cohort, six of them were validated to be significant prognostic factors to predict DFS and overall survival (OS) in the validation cohort, namely fibroblast growth factor 2 (FGF-2), growth-regulated oncogene (GRO), interleukin 8 (IL-8), interferon gamma-induced protein 10 (IP-10), vascular endothelial growth factor (VEGF), and interferon alpha-2 (IFN-α2). By integrating six cytokines and three clinical characteristics, we developed a CBPC to predict the recurrence and 3-year OS of HCC patients (sensitivity, 0.648; specificity, 0.918). In the validation cohort, the CBPC were confirmed to have significant predictive power for predicting tumour recurrence and OS (sensitivity, 0.585; specificity, 0.857). Interestingly, IFN-α2 was the only cytokine being independent prognostic factor in both patient cohorts.

CONCLUSION

Our study verifies the presence of specific cytokine-phenotype associations with patient prognosis in HCC. The CBPC developed include multiple circulating cytokines and may serve as a novel screening approach for identifying HCC patients with a high risk of post-resection recurrence and shorter OS. These individuals may also be suitable for cytokine-targeted therapies.

Angiogenesis inhibitors in cancer therapy: mechanistic perspective on classification and treatment rationales

Angiogenesis, a process of new blood vessel formation, is a prerequisite for tumour growth to supply the proliferating tumour with oxygen and nutrients. The angiogenic process may contribute to tumour progression, invasion and metastasis, and is generally accepted as an indicator of tumour prognosis. Therefore, targeting tumour angiogenesis has become of high clinical relevance. The current review aimed to highlight mechanistic details of anti-angiogenic therapies and how they relate to classification and treatment rationales. Angiogenesis inhibitors are classified into either direct inhibitors that target endothelial cells in the growing vasculature or indirect inhibitors that prevent the expression or block the activity of angiogenesis inducers. The latter class extends to include targeted therapy against oncogenes, conventional chemotherapeutic agents and drugs targeting other cells of the tumour micro-environment. Angiogenesis inhibitors may be used as either monotherapy or in combination with other anticancer drugs. In this context, many preclinical and clinical studies revealed higher therapeutic effectiveness of the combined treatments compared with individual treatments. The proper understanding of synergistic treatment modalities of angiogenesis inhibitors as well as their wide range of cellular targets could provide effective tools for future therapies of many types of cancer.

A murine-human chimeric IgG antibody against vascular endothelial growth factor receptor 2 inhibits angiogenesis in vitro

Vascular endothelial growth factor receptor 2 (VEGFR2) has been reported to play an important role in angiogenesis and tumorigenesis. A murine anti-VEGFR2 mAb (A8H1) has been established in a previous study. To reduce the incompatibility of the murine mAb for human use, the chimeric anti-VEGFR2-IgG was developed by genetic recombination of the variable regions of the A8H1 antibody and the constant regions of human IgG, and was expressed in Sp2/0 cells transfected with the two recombinant vectors containing the heavy chain and the light chain regions. After screening, clone 2F12 was selected and was found to stably secrete the murine-human chimeric anti-VEGFR2-IgG (coded 2F12). This chimeric IgG maintained the specificity and the affinity of the parental murine antibody against VEGFR2, and effectively identified VEGFR2 expressed on the surface of HUVECs and BEL-7402 cells. Furthermore, the 2F12 antibody demonstrated inhibition of angiogenesis in vitro, such as proliferation, migration, invasion and tube formation of HUVECs. This murine-human chimeric IgG may be considered for further development as an anti-angiogenesis and anti-tumor agent.

Activity of the fibroblast growth factor receptor inhibitors dovitinib (TKI258) and NVP-BGJ398 in human endometrial cancer cells

The recent identification of activating fibroblast growth factor receptor 2 (FGFR2) mutations in endometrial cancer has generated an opportunity for a novel target-based therapy. Here, we explore the therapeutic potential of 2 FGFR inhibitors, the multikinase inhibitor dovitinib (TKI258) and the more selective FGFR inhibitor NVP-BGJ398 for the treatment of endometrial cancer. We examined the effects of both inhibitors on tumor cell growth, FGFR2 signaling, cell cycle, and apoptosis using a panel of 20 molecularly characterized human endometrial cancer cell lines. Anchorage-independent growth was studied using soft agar assays. In vivo studies were conducted using endometrial cancer xenograft models. Cell lines with activating FGFR2 mutations (S252W, N550K) were more sensitive to dovitinib or NVP-BGJ398 when compared with their FGFR2 wild-type counterparts (P = 0.073 and P = 0.021, respectively). Both agents inhibited FGFR2 signaling, induced cell-cycle arrest, and significantly increased apoptosis in FGFR2-mutant lines. In vitro, dovitinib and NVP-BGJ398 were both potent at inhibiting cell growth of FGFR2-mutant endometrial cancer cells, but the activity of dovitinib was less restricted to FGFR2-mutant lines when compared with NVP-BGJ398. In vivo, dovitinib and NVP-BGJ398 significantly inhibited the growth of FGFR2-mutated endometrial cancer xenograft models. In addition, dovitinib showed significant antitumor activity in FGFR2 wild-type endometrial cancer xenograft models including complete tumor regressions in a long-term in vivo study. Dovitinib and NVP-BGJ398 warrant further clinical evaluation in patients with FGFR2-mutated endometrial cancer. Dovitinib may have antitumor activity in endometrial cancer beyond FGFR2-mutated cases and may permit greater flexibility in patient selection.