Establishment and characterization of 7 novel hepatocellular carcinoma cell lines from patient-derived tumor xenografts

GPRC5A promotes gallbladder cancer metastasis by upregulating TNS4 via the JAK2-STAT3 pathway

Aberrant expression of G protein-coupled receptor class C group 5 member A (GPRC5A) has been reported in multiple cancers and is closely related to patient prognosis. However, the mechanistic role of GPRC5A in gallbladder cancer (GBC) remains unclear. Here, we determined tumor expression levels of GPRC5A and the molecular mechanisms by which GPRC5A regulates gallbladder cancer metastasis. We found that GPRC5A was significantly upregulated in GBC, correlating with poorer patient survival. Knocking down GPRC5A inhibited GBC cell metastasis both in vitro and in vivo. GRPRC5A knockdown resulted in downregulation of TNS4 expression through the JAK2-STAT3 axis. Clinically, GPRC5A expression positively correlated with TNS4. Finally, STAT3 bound to TNS4's promoter region, inducing its expression. Overall, GPRC5A showed high expression in GBC tissues, associated with poor patient prognosis. Our findings first demonstrate that the GPRC5A-JAK2-STAT3-TNS4 pathway promotes GBC cell metastasis, suggesting potential therapy targets.

The G protein-coupled receptor GPRC5A-a phorbol ester and retinoic acid-induced orphan receptor with roles in cancer, inflammation, and immunity

GPRC5A is the first member of a new class of orphan receptors coupled to G proteins, which also includes GPRC5B, GPRC5C, and GPRC5D. Since its cloning and identification in the 1990s, substantial progress has been made in understanding the possible functions of this receptor. GPRC5A has been implicated in a variety of cellular events, such as cytoskeleton reorganization, cell proliferation, cell cycle regulation, migration, and survival. It appears to be a central player in different pathological processes, including tumorigenesis, inflammation, immune response, and tissue damage. The levels of GPRC5A expression differ depending on the type of cancer, with increased expression in colon, pancreas, and prostate cancers; decreased expression in lung cancer; and varied results in breast cancer. In this review, we discuss the early discovery of GPRC5A as a phorbol ester-induced gene and later as a retinoic acid-induced gene, its regulation, and its participation in important canonical pathways related to numerous types of tumors and inflammatory processes. GPRC5A represents a potential new target for cancer, inflammation, and immunity therapies.

Synergistic Effect of Lenvatinib and Chemotherapy in Hepatocellular Carcinoma Using Preclinical Models

Purpose

The current study aimed to evaluate the synergistic efficacy of lenvatinib and FOLFOX (infusional fluorouracil (FU), folinic acid, and oxaliplatin) in hepatocellular carcinoma (HCC) using patient-derived xenograft (PDX) and PDX-derived organotypic spheroid (XDOTS) models in vivo and in vitro.

Methods

PDX and matched XDOTS models originating from three patients with HCC were established. All models were divided into four groups and treated with drugs alone or in combination. Tumor growth in the PDX models was measured and recorded, and angiogenesis and phosphorylation of the vascular endothelial growth factor receptor (VEGFR2), rearranged during transfection (RET), and extracellular signal-regulated kinase (ERK) were detected using immunohistochemistry and Western blot assays. The proliferative ability of XDOTS was evaluated through active staining and immunofluorescence staining, and the effect of the combined medication was evaluated using the Celltiter-Glo luminescent cell viability assay.

Results

Three PDX models with genetic characteristics similar to those of the original tumors were successfully established. Combining lenvatinib with FOLFOX led to a higher tumor growth inhibition rate than individual therapies (P < 0.01). Immunohistochemical analysis demonstrated that the combined treatment significantly inhibited the proliferation and angiogenesis of PDX tissues (P < 0.05), and Western blot analysis showed that the combined treatment significantly inhibited the phosphorylation of VEGFR2, RET, and ERK compared with single-agent treatment. Additionally, all three matched XDOTS models were successfully cultured with satisfactory activity and proliferation, and the combined therapies led to better suppression of XDOTS growth compared with individual therapy (P < 0.05).

Conclusion

Lenvatinib combined with FOLFOX had a synergistic antitumor effect in HCC PDX and XDOTS models by inhibiting the phosphorylation of VEGFR, RET, and ERK.

Combined inhibition of FGFR4 and VEGFR signaling enhances efficacy in FGF19 driven hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is an aggressive liver malignancy that is difficult to treat with no approved biomarker based targeted therapies. FGF19-FGFR4 signaling blockade has been recently identified as a promising avenue for treatment of a subset of HCC patients. Using HCC relevant xenograft and PDX models, we show that Lenvatinib, an approved multi-kinase inhibitor, strongly enhanced the efficacy of FGFR4 inhibitor H3B-6527. This enhanced combination effect is not due to enhanced FGFR4 inhibition and it is likely due to cell non-autonomous VEGFR activity of Lenvatinib. This cell non-autonomous mode of action was further supported by strong in vivo combination efficacy with the mouse specific VEGFR2 antibody, DC101, which cannot cell-autonomously inhibit pathways in human xenografts. Mechanistic studies showed that the combination resulted in enhanced efficacy through increased anti-angiogenic and anti-tumorigenic activities. Overall, our results indicate that this combination can be a highly effective treatment option for FGF19 driven HCC patients, and provide preclinical validation of a combination that can be readily tested in the clinical setting.

Elucidating the Molecular Basis of Sorafenib Resistance in HCC: Current Findings and Future Directions

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related mortality worldwide. Sorafenib is the first multi-tyrosine kinase inhibitor approved for HCC and it has represented the standard of care for advanced HCC for almost 10 years, offering a survival benefit when compared to placebo. However, this benefit is limited, showing rare objective responses and a disease control rate approaching 50–60%, with most patients experiencing disease progression at 6 months. These scant results dictate the urgent need for strategies to overcome both primary and acquired resistance. Herein we report several mechanisms supporting resistance to sorafenib in HCC patients, including activation of oncogenic pathways. Among these, the AKT/mTOR pathway plays a crucial role being at the crossroad of multiple driving events. Autophagy, multidrug-resistant phenotype, hypoxia-related mechanisms and endoplasmic reticulum stress are gaining more and more relevance as crucial events driving the response to anticancer drugs, including sorafenib. Several HCC-specific miRNAs take part to the regulation of these cellular processes. Remarkably, molecularly targeted strategies able to overcome resistance in these settings have also been reported. So far, the vast majority of data has been derived from laboratory studies, which means the need for an extensive validation. Indeed, most of the possible drug associations displaying promising effects in improving sorafenib efficacy herein described derive from preclinical explorations. Notably, data obtained in animal models can be inconsistent with regard to the human disease for efficacy, safety, side effects, best formulation and pharmacokinetics. However, they represent the necessary preliminary step to improve the management of advanced HCC.

Novel Cyclophilin Inhibitor Decreases Cell Proliferation and Tumor Growth in Models of Hepatocellular Carcinoma

Simple Summary

Cyclophilins, a family of proteins with peptidyl prolyl isomerase activity, have been found to be overexpressed in several cancers, including hepatocellular carcinoma (HCC), and their expression is correlated to a poor prognosis. Cyclophilins play an important role in proliferation and cancer resistance in HCC. In this study, we evaluated the potential capacity of cyclophilin inhibitors as a treatment against HCC. We showed that our selected cyclophilin inhibitor, NV651, was able to decrease cell proliferation in vitro and induce an accumulation of cells in the G₂/M phase due to a mitotic block. We could also confirm its capacity to decrease tumor growths in mice and its safety in vitro as well as in vivo.

Abstract

Hepatocellular carcinoma (HCC), the most common primary liver cancer, is usually diagnosed in its late state. Tyrosine kinase inhibitors such as sorafenib and regorafenib are one of the few treatment options approved for advanced HCC and only prolong the patient’s life expectancy by a few months. Therefore, there is a need for novel effective treatments. Cyclophilins are intracellular proteins that catalyze the cis/trans isomerization of peptide bonds at proline residues. Cyclophilins are known to be overexpressed in HCC, affecting therapy resistance and cell proliferation. In the present study, we explored the potential of cyclophilin inhibitors as new therapeutic options for HCC in vitro and in vivo. Our results showed that the novel cyclophilin inhibitor, NV651, was able to significantly decrease proliferation in a diverse set of HCC cell lines. The exposure of HCC cells to NV651 caused an accumulation of cells during mitosis and consequent accumulation in the G₂/M phase of the cell cycle. NV651 reduced tumor growth in vivo using an HCC xenograft model without affecting the body weights of the animals. The safety aspects of NV651 were also confirmed in primary human hepatocytes without any cytotoxic effects. Based on the results obtained in this study, we propose NV651 as a potential treatment strategy for HCC.

Cytotoxicity Evaluation of Dimethoxy and Trimethoxy Indanonic Spiroisoxazolines Against Cancerous Liver Cells

Background:

3'-(3,4-dimethoxyphenyl)-4'-(4-(methylsulfonyl)phenyl)-4'H-spiro [indene-2,5'-isoxazol]-1(3H)-one and 4'-(4-(methylsulfonyl)phenyl)-3'-(3,4,5-trimethoxyphenyl)- 4'H-spiro[indene-2,5'-isoxazol]-1(3H)-one compounds containing indanonic spiroisoxazoline core are widely known for their antiproliferative activities and investigation of tubulin binding modes.

Objective:

To evaluate the cytotoxicity effect of Dimethoxy and Trimethoxy Indanonic Spiroisoxazolines against HepG2 cancerous liver cell line and to perform a comparison with other known anti-liver cancer drugs.

Methods:

The evaluation of cytotoxicity of dimethoxy and trimethoxy indanonic spiroisoxazoline compounds, Oxaliplatin, Doxorubicin, 5-fluorouracil and Cisplatin against HepG2 (hepatocellular liver carcinoma) cell line has been performed using MTT assay and analyzed by GraphPad PRISM software (version 8.0.2).

Results:

Potent cytotoxicity effects against HepG2 cell line, comparable to Cisplatin (IC50= 0.047±0.0045 µM), Oxaliplatin (IC50= 0.0051µM), Doxorubicin (IC50= 0.0014µM) and 5- fluorouracil (IC50= 0.0089 µM), were shown by both dimethoxy (IC50= 0.059±0.012 µM) and trimethoxy (IC50= 0.086±0.019 µM) indanonic spiroisoxazoline compounds.

Conclusion:

In vitro biological evaluations revealed that dimethoxy and trimethoxy indanonic spiroisoxazoline compounds are good candidates for the development of new anti-liver cancer agents.

Establishment and Preclinical Therapy of Patient-derived Hepatocellular Carcinoma Xenograft Model

Hepatocellular carcinoma (HCC) is a world-wide health problem. Poor and delayed diagnoses as well as high recurrence rate resulting in high mortality rate. In this study, we established a patient-derived xenograft (PDX) model from HCC patient, and continuously maintained with subcutaneous passage more than 20 times. This HCC PDX tumor exhibited the same histological characteristics with the HCC patient and could be used to verify therapeutic effect of liver cancer. We further evaluated this PDX model by experimental chemotherapy, demonstrating that this HCC PDX model was sensitive to sorafenib treatment. Further, the potential of natural killer cell-based immunotherapy for HCC was tested using this model. We found that NK92 cells effectively suppressed the tumor growth in vivo and prolonged the survival time of HCC-bearing PDX mice. This study indicates that HCC PDX model is a good platform to testify the efficacy of preclinical chemotherapy and immunotherapy.

Advances in molecular classification and precision oncology in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) arises from hepatocytes through the sequential accumulation of multiple genomic and epigenomic alterations resulting from Darwinian selection. Genes from various signalling pathways such as telomere maintenance, Wnt/β-catenin, P53/cell cycle regulation, oxidative stress, epigenetic modifiers, AKT/mTOR and MAP kinase are frequently mutated in HCC. Several subclasses of HCC have been identified based on transcriptomic dysregulation and genetic alterations that are closely related to risk factors, pathological features and prognosis. Undoubtedly, integration of data obtained from both preclinical models and human studies can help to accelerate the identification of robust predictive biomarkers of response to targeted biotherapy and immunotherapy. The aim of this review is to describe the main advances in HCC in terms of molecular biology and to discuss how this knowledge could be used in clinical practice in the future.

Novel patient-derived preclinical models of liver cancer

Preclinical models of cancer based on the use of human cancer cell lines and mouse models have enabled discoveries that have been successfully translated into patients. And yet the majority of clinical trials fail, emphasising the urgent need to improve preclinical research to better interrogate the potential efficacy of each therapy and the patient population most likely to benefit. This is particularly important for liver malignancies, which lack highly efficient treatments and account for hundreds of thousands of deaths around the globe. Given the intricate network of genetic and environmental factors that contribute to liver cancer development and progression, the identification of new druggable targets will mainly depend on establishing preclinical models that mirror the complexity of features observed in patients. The development of new 3D cell culture systems, originating from cells/tissues isolated from patients, might create new opportunities for the generation of more specific and personalised therapies. However, these systems are unable to recapitulate the tumour microenvironment and interactions with the immune system, both proven to be critical influences on therapeutic outcomes. Patient-derived xenografts, in particular with humanised mouse models, more faithfully mimic the physiology of human liver cancer but are costly and time-consuming, which can be prohibitive for personalising therapies in the setting of an aggressive malignancy. In this review, we discuss the latest advances in the development of more accurate preclinical models to better understand liver cancer biology and identify paradigm-changing therapies, stressing the importance of a bi-directional communicative flow between clinicians and researchers to establish reliable model systems and determine how best to apply them to expanding our current knowledge.

Hepatocellular Carcinoma Xenografts Established From Needle Biopsies Preserve the Characteristics of the Originating Tumors

Hepatocellular carcinoma (HCC) is the second leading cause of cancer‐related deaths worldwide. Treatment options for patients with advanced‐stage disease are limited. A major obstacle in drug development is the lack of an in vivo model that accurately reflects the broad spectrum of human HCC. Patient‐derived xenograft (PDX) tumor mouse models could overcome the limitations of cancer cell lines. PDX tumors maintain the genetic and histologic heterogeneity of the originating tumors and are used for preclinical drug development in various cancers. Controversy exists about their genetic and molecular stability through serial passaging in mice. We aimed to establish PDX models from human HCC biopsies and to characterize their histologic and molecular stability during serial passaging. A total of 54 human HCC needle biopsies that were derived from patients with various underlying liver diseases and tumor stages were transplanted subcutaneously into immunodeficient, nonobese, diabetic/severe combined immunodeficiency gamma‐c mice; 11 successfully engrafted. All successfully transplanted HCCs were Edmondson grade III or IV. HCC PDX tumors retained the histopathologic, transcriptomic, and genomic characteristics of the original HCC biopsies over 6 generations of retransplantation. These characteristics included Edmondson grade, expression of tumor markers, tumor gene signature, tumor‐associated mutations, and copy number alterations. Conclusion: PDX mouse models can be established from undifferentiated HCCs, with an overall success rate of approximately 20%. The transplanted tumors represent the entire spectrum of the molecular landscape of HCCs and preserve the characteristics of the originating tumors through serial passaging. HCC PDX models are a promising tool for preclinical personalized drug development.

Retracted Article: MiR-206 reduced the malignancy of hepatocellular carcinoma cells in vitro by inhibiting MET and CTNNB1 gene expressions

The anti-cancer role of miR-206 in hepatocellular carcinoma (HCC) cells has been reported, but its mechanism of action remains poorly understood.

GPRC5A: An Emerging Biomarker in Human Cancer

Aberrant expression of G protein-coupled receptors (GPCRs) is frequently associated with tumorigenesis. G Protein-coupled receptor class C group 5 member A (GPRC5A) is a member of the GPCR superfamily, is expressed preferentially in lung tissues, and is regulated by various entities at multiple levels. GPRC5A exerts a tumor suppressive role in lung cancer and GPRC5A deletion promotes lung tumor initiation and progression. Recent advances have highlighted that GPRC5A dysregulation is found in various human cancers and is related to many tumor-associated signaling pathways, including the cyclic adenosine monophosphate (cAMP), nuclear factor (NF)-κB, signal transducer and activator of transcription (STAT) 3, and focal adhesion kinase (FAK)/Src signaling. This review aimed to summarize our updated view on the biology and regulation of GPRC5A, its expression in human cancers, and the linked signaling pathways. A better comprehension of the underlying cellular and molecular mechanisms of GPRC5A will provide novel insights into its potential diagnostic and therapeutic value.

In vivo acquired sorafenib-resistant patient-derived tumor model displays alternative angiogenic pathways, multi-drug resistance and chromosome instability

Acquired resistance to targeted therapies is an important clinical challenge. Research focusing on acquired resistance is hindered by the lack of relevant model systems. In the present study, the generation and characterization of an in vivo acquired sorafenib-resistant hepatocellular carcinoma (HCC) xenograft model derived from a patient tumor is reported. A cancer cell line (LIXC-004SR) was generated from a tumor that had developed following ~100 days of sorafenib treatment of a HCC patient-derived xenograft (PDX) model (LIX004). The xenograft tumors derived from this cell line demonstrated sorafenib-resistance in vivo. By contrast, a cell line (LIXC-004NA) generated from a vehicle-treated LIX004 PDX model remained sensitive to sorafenib in vivo. Following treatment with sorafenib in vivo, angiogenesis was significantly elevated in the LIXC-004SR tumors when compared with that in the LIXC-004NA tumors. The LIXC-004SR cell culture supernatant stimulated human umbilical vein endothelial cell proliferation and extracellular-signal-regulated kinase and protein kinase B phosphorylation, which can only be inhibited by the combination of sorafenib and a fibroblast growth factor receptor 1 (FGFR1) inhibitor, AZD4547. The tumor growth of the sorafenib-resistant LIXC-004SR xenograft was inhibited by the FGFR1 inhibitor in vivo, suggesting that one of the underlying mechanisms of the acquired resistance is likely due to activation of alternative angiogenic pathways. The LIXC-004SR cell line also exhibited signs of multi-drug resistance and genetic instability. Taken together, these data suggest that this in vivo model of acquired resistance from a PDX model may reflect sorafenib-resistance in certain patients and may facilitate drug resistance research, as well as contributing to the clinical prevention and management of drug resistance.

Lenvatinib inhibits angiogenesis and tumor fibroblast growth factor signaling pathways in human hepatocellular carcinoma models

Unresectable hepatocellular carcinoma (uHCC) is one of the most lethal and prevalent cancers worldwide, and current systemic therapeutic options for uHCC are limited. Lenvatinib, a multiple receptor tyrosine kinase inhibitor targeting vascular endothelial growth factor receptors (VEGFRs) and fibroblast growth factor receptors (FGFRs), recently demonstrated a treatment effect on overall survival by statistical confirmation of noninferiority to sorafenib in a phase 3 study of uHCC. Here, we investigated mechanisms underlying the antitumor activity of lenvatinib in preclinical HCC models. In vitro proliferation assay of nine human HCC cell lines showed that lenvatinib selectively inhibited proliferation of FGF signal-activated HCC cells including FGF19-expressing Hep3B2.1-7. Lenvatinib suppressed phosphorylation of FRS2, a substrate of FGFR1-4, in these cells in a concentration-dependent manner. Lenvatinib inhibited in vivo tumor growth in Hep3B2.1-7 and SNU-398 xenografts and decreased phosphorylation of FRS2 and Erk1/2 within the tumor tissues. Lenvatinib also exerted antitumor activity and potently reduced tumor microvessel density in PLC/PRF/5 xenograft model and two HCC patient-derived xenograft models. These results suggest that lenvatinib has antitumor activity consistently across diverse HCC models, and that targeting of tumor FGF signaling pathways and anti-angiogenic activity underlies its antitumor activity against HCC tumors.

Patient-derived multicellular tumor spheroids towards optimized treatment for patients with hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide and has poor prognosis. Specially, patients with HCC usually have poor tolerance of systemic chemotherapy, because HCCs develop from chronically damaged tissue that contains considerable inflammation, fibrosis, and cirrhosis. Since HCC exhibits highly heterogeneous molecular characteristics, a proper in vitro system is required for the study of HCC pathogenesis. To this end, we have established two new hepatitis B virus (HBV) DNA-secreting HCC cell lines from infected patients.

Methods

Based on these two new HCC cell lines, we have developed chemosensitivity assays for patient-derived multicellular tumor spheroids (MCTSs) in order to select optimized anti-cancer drugs to provide more informative data for clinical drug application. To monitor the effect of the interaction of cancer cells and stromal cells in MCTS, we used a 3D co-culture model with patient-derived HCC cells and stromal cells from human hepatic stellate cells, human fibroblasts, and human umbilical vein endothelial cells to facilitate screening for optimized cancer therapy.

Results

To validate our system, we performed a comparison of chemosensitivity of the three culture systems, which are monolayer culture system, tumor spheroids, and MCTSs of patient-derived cells, to sorafenib, 5-fluorouracil, and cisplatin, as these compounds are typically standard therapy for advanced HCC in South Korea.

Conclusion

In summary, these findings suggest that the MCTS culture system is the best methodology for screening for optimized treatment for each patients with HCC, because tumor spheroids not only mirror the 3D cellular context of the tumors but also exhibit therapeutically relevant pathophysiological gradients and heterogeneity of in vivo tumors.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0752-0) contains supplementary material, which is available to authorized users.

PDXliver: a database of liver cancer patient derived xenograft mouse models

Background

Liver cancer is the second leading cause of cancer-related deaths and characterized by heterogeneity and drug resistance. Patient-derived xenograft (PDX) models have been widely used in cancer research because they reproduce the characteristics of original tumors. However, the current studies of liver cancer PDX mice are scattered and the number of available PDX models are too small to represent the heterogeneity of liver cancer patients. To improve this situation and to complement available PDX models related resources, here we constructed a comprehensive database, PDXliver, to integrate and analyze liver cancer PDX models.

Description

Currently, PDXliver contains 116 PDX models from Chinese liver cancer patients, 51 of them were established by the in-house PDX platform and others were curated from the public literatures. These models are annotated with complete information, including clinical characteristics of patients, genome-wide expression profiles, germline variations, somatic mutations and copy number alterations. Analysis of expression subtypes and mutated genes show that PDXliver represents the diversity of human patients. Another feature of PDXliver is storing drug response data of PDX mice, which makes it possible to explore the association between molecular profiles and drug sensitivity. All data can be accessed via the Browse and Search pages. Additionally, two tools are provided to interactively visualize the omics data of selected PDXs or to compare two groups of PDXs.

Conclusion

As far as we known, PDXliver is the first public database of liver cancer PDX models. We hope that this comprehensive resource will accelerate the utility of PDX models and facilitate liver cancer research. The PDXliver database is freely available online at: http://www.picb.ac.cn/PDXliver/

Optical imaging of gastric cancer with near-infrared heptamethine carbocyanine fluorescence dyes

Near-infrared fluorescence (NIRF) imaging agents are promising tools for noninvasive cancer imaging. Here, we explored the tumor-specific targeting ability of NIRF heptamethine carbocyanine MHI-148 dye in cultured gastric cancer cells, gastric cancer cell-derived and patient-derived tumor xenograft (PDX) models. We show that the NIRF dye specifically accumulated in tumor regions of both xenograft models, suggesting the potential utility of the dye for tumor-specific imaging and targeting in gastric cancer. We also demonstrated significant correlations between NIRF signal intensity and tumor volume in PDX models. Mechanistically, the higher cellular uptake of MHI-148 in gastric cancer cells than in normal cells was stimulated by hypoxia and activation of a group of organic anion-transporting polypeptide (OATP) genes. Importantly, this NIRF dye was not retained in inflammatory stomach tissues induced by gastric ulcer in mice. In addition, fresh clinical gastric tumor specimens, when perfused with NIR dye, exhibited increased uptake of NIR dye in situ. Together, these results show the possibility of using NIRF dyes as novel candidate agents for clinical imaging and detection of gastric cancer.

H3B-6527 Is a Potent and Selective Inhibitor of FGFR4 in FGF19-Driven Hepatocellular Carcinoma

Activation of the fibroblast growth factor receptor FGFR4 by FGF19 drives hepatocellular carcinoma (HCC), a disease with few, if any, effective treatment options. While a number of pan-FGFR inhibitors are being clinically evaluated, their application to FGF19-driven HCC may be limited by dose-limiting toxicities mediated by FGFR1-3 receptors. To evade the potential limitations of pan-FGFR inhibitors, we generated H3B-6527, a highly selective covalent FGFR4 inhibitor, through structure-guided drug design. Studies in a panel of 40 HCC cell lines and 30 HCC PDX models showed that FGF19 expression is a predictive biomarker for H3B-6527 response. Moreover, coadministration of the CDK4/6 inhibitor palbociclib in combination with H3B-6527 could effectively trigger tumor regression in a xenograft model of HCC. Overall, our results offer preclinical proof of concept for H3B-6527 as a candidate therapeutic agent for HCC cases that exhibit increased expression of FGF19. Cancer Res; 77(24); 6999-7013. ©2017 AACR.

Generation of matched patient-derived xenograft in vitro-in vivo models using 3D macroporous hydrogels for the study of liver cancer

Hepatocellular carcinoma (HCC) is the third leading cause of cancer death worldwide, often manifesting at the advanced stage when cure is no longer possible. The discrepancy between preclinical findings and clinical outcome in HCC is well-recognized. So far, sorafenib is the only targeted therapy approved as first-line therapy for patients with advanced HCC. There is an urgent need for improved preclinical models for the development of HCC-targeted therapies. Patient-derived xenograft (PDX) tumor models have been shown to closely recapitulate human tumor biology and predict patient drug response. However, the use of PDX models is currently limited by high costs and low throughput. In this study, we engineered in vitro conditions conducive for the culture of HCC-PDX organoids derived from a panel of 14 different HCC-PDX lines through the use of a three-dimensional macroporous cellulosic sponge system. To validate the in vitro HCC-PDX models, both in vivo and in vitro HCC-PDX models were subjected to whole exome sequencing and RNA-sequencing. Correlative studies indicate strong concordance in genomic and transcriptomic profiles as well as intra-tumoral heterogeneity between each matched in vitro-in vivo HCC-PDX pairs. Furthermore, we demonstrate the feasibility of using these in vitro HCC-PDX models for drug testing, paving the way for more efficient preclinical studies in HCC drug development.

Guidance to rational use of pharmaceuticals in gallbladder sarcomatoid carcinoma using patient-derived cancer cells and whole exome sequencing

PURPOSE

Gallbladder sarcomatoid carcinoma is a rare cancer with no clinical standard treatment. With the rapid development of next generation sequencing, it has been able to provide reasonable treatment options for patients based on genetic variations. However, most cancer drugs are not approval for gallbladder sarcomatoid carcinoma indications. The correlation between drug response and a genetic variation needs to be further elucidated.

EXPERIMENTAL DESIGN

Three patient-derived cells-JXQ-3D-001, JXQ-3D-002, and JXQ-3D-003, were derived from biopsy samples of one gallbladder sarcomatoid carcinoma patient with progression and have been characterized. In order to study the relationship between drug sensitivity and gene alteration, genetic mutations of three patient-derived cells were discovered by whole exome sequencing, and drug screening has been performed based on the gene alterations and related signaling pathways that are associated with drug targets.

RESULTS

It has been found that there are differences in biological characteristics such as morphology, cell proliferation, cell migration and colony formation activity among these three patient-derived cells although they are derived from the same patient. Their sensitivities to the chemotherapy drugs-Fluorouracil, Doxorubicin, and Cisplatin are distinct. Moreover, none of common chemotherapy drugs could inhibit the proliferations of all three patient-derived cells. Comprehensive analysis of their whole exome sequencing demonstrated that tumor-associated genes TP53, AKT2, FGFR3, FGF10, SDHA, and PI3KCA were mutated or amplified. Part of these alterations are actionable. By screening a set of compounds that are associated with the genetic alteration, it has been found that GDC-0941 and PF-04691502 for PI3K-AKT-mTOR pathway inhibitors could dramatically decrease the proliferation of three patient-derived cells. Importantly, expression of phosphorylated AKT and phosphorylated S6 were markedly decreased after treatments with PI3K-AKT-mTOR pathway inhibitors GDC-0941 (0.5 μM) and PF-04691502 (0.1 μM) in all three patient-derived cells. These data suggested that inhibition of the PI3K-AKT-mTOR pathway that was activated by PIK3CA amplification in all three patient-derived cells could reduce the cell proliferation.

CONCLUSIONS

A patient-derived cell model combined with whole exome sequencing is a powerful tool to elucidate relationship between drug sensitivities and genetic alternations. In these gallbladder sarcomatoid carcinoma patient-derived cells, it is found that PIK3CA amplification could be used as a biomarker to indicate PI3K-AKT-mTOR pathway activation. Block of the pathway may benefit the gallbladder sarcomatoid carcinoma patient with this alternation in hypothesis. The real efficacy needs to be confirmed in vivo or in a clinical trial.

Anti-GPC3-CAR T Cells Suppress the Growth of Tumor Cells in Patient-Derived Xenografts of Hepatocellular Carcinoma

BACKGROUND

The lack of a general clinic-relevant model for human cancer is a major impediment to the acceleration of novel therapeutic approaches for clinical use. We propose to establish and characterize primary human hepatocellular carcinoma (HCC) xenografts that can be used to evaluate the cytotoxicity of adoptive chimeric antigen receptor (CAR) T cells and accelerate the clinical translation of CAR T cells used in HCC.

METHODS

Primary HCCs were used to establish the xenografts. The morphology, immunological markers, and gene expression characteristics of xenografts were detected and compared to those of the corresponding primary tumors. CAR T cells were adoptively transplanted into patient-derived xenograft (PDX) models of HCC. The cytotoxicity of CAR T cells in vivo was evaluated.

RESULTS

PDX1, PDX2, and PDX3 were established using primary tumors from three individual HCC patients. All three PDXs maintained original tumor characteristics in their morphology, immunological markers, and gene expression. Tumors in PDX1 grew relatively slower than that in PDX2 and PDX3. Glypican 3 (GPC3)-CAR T cells efficiently suppressed tumor growth in PDX3 and impressively eradicated tumor cells from PDX1 and PDX2, in which GPC3 proteins were highly expressed.

CONCLUSION

GPC3-CAR T cells were capable of effectively eliminating tumors in PDX model of HCC. Therefore, GPC3-CAR T cell therapy is a promising candidate for HCC treatment.

GPRC5A is a potential oncogene in pancreatic ductal adenocarcinoma cells that is upregulated by gemcitabine with help from HuR

GPRC5A is an orphan G-protein coupled receptor with an intriguing dual behavior, acting as an oncogene in some cancers and as a tumor suppressor in other cancers. In the pancreatic cancer context, very little is known about GPRC5A. By analyzing messenger RNA (mRNA) expression data from 675 human cancer cell lines and 10 609 samples from The Cancer Genome Atlas (TCGA) we found that GPRC5A's abundance in pancreatic cancer is highest (cell lines) or second highest (TCGA) among all tissues and cancer types. Further analyses of an independent set of 252 pancreatic normal and cancer samples showed GPRC5A mRNA to be more than twofold upregulated in primary tumor samples compared with normal pancreas (P-value<10⁻⁵), and even further upregulated in pancreatic cancer metastases to various organs (P-value=0.0021). Immunostaining of 208 cores (103 samples) of a tissue microarray showed generally low expression of GPRC5A protein in normal pancreatic ductal cells; on the other hand, in primary and metastatic samples, GPRC5A protein levels were dramatically increased in pancreatic ductal cells. In vitro studies of multiple pancreatic cancer cell lines showed that an increase in GPRC5A protein levels promoted pancreatic cancer cell growth and migration. Unexpectedly, when we treated pancreatic cancer cell lines with gemcitabine (2′,2′-difluorodeoxycytidine), we observed an increase in GPRC5A protein abundance. On the other hand, when we knocked down GPRC5A we sensitized pancreatic cancer cells to gemcitabine. Through further experimentation we showed that the monotonic increase in GPRC5A protein levels that we observe for the first 18 h following gemcitabine treatment results from interactions between GPRC5A's mRNA and the RNA-binding protein HuR, which is an established key mediator of gemcitabine's efficacy in cancer cells. As we discovered, the interaction between GPRC5A and HuR is mediated by at least one HuR-binding site in GPRC5A's mRNA. Our findings indicate that GPRC5A is part of a complex molecular axis that involves gemcitabine and HuR, and, possibly, other genes. Further work is warranted before it can be established unequivocally that GPRC5A is an oncogene in the pancreatic cancer context.

Explant culture of sarcoma patients' tissue

Human sarcomas comprise a heterogeneous group of rare tumors that affect soft tissues and bone. Due to the scarcity and heterogeneity of these diseases, patient-derived cells that can be used for preclinical research are limited. In this study, we investigated whether the tissue explant technique can be used to obtain sarcoma cell lines from fresh as well as viable frozen tissue obtained from 8 out of 12 soft tissue and 9 out of 13 bone tumor entities as defined by the World Health Organization. The success rate, defined as the percent of samples that yielded sufficient numbers of outgrowing cells to be frozen, and the time to freeze were determined for a total of 734 sarcoma tissue specimens. In 552 cases (75%) enough cells were obtained to be frozen at early passage. Success rates were higher in bone tumors (82%) compared with soft tissue tumors (68%), and the mean time to freezing was lower in bone tumors (65 days) compared with soft tissue tumors (84 days). Overall, from 40% of the tissues cells could be frozen at early passage within <2 month after tissue removal. Comparable results as with fresh tissue were obtained after explant of viable frozen patient-derived material. In a selected number of bone and soft tissue sarcoma entities, conventional karyotyping and/or FISH (fluorescence in situ hybridization) analysis revealed a high amount (>60%) of abnormal cells in 41% of analyzed samples, especially in bone sarcomas (osteosarcoma and Ewing sarcoma). In conclusion, the explant technique is well suited to establish patient-derived cell lines for a large majority of bone and soft tissue sarcoma entities with adequate speed. This procedure thus opens the possibility for molecular analysis and drug testing for therapeutic decision making even during patient treatment.

Review on near-infrared heptamethine cyanine dyes as theranostic agents for tumor imaging, targeting, and photodynamic therapy

A class of near-infrared fluorescence (NIRF) heptamethine cyanine dyes that are taken up and accumulated specifically in cancer cells without chemical conjugation have recently emerged as promising tools for tumor imaging and targeting. In addition to their fluorescence and nuclear imaging-based tumor-imaging properties, these dyes can be developed as drug carriers to safely deliver chemotherapy drugs to tumors. They can also be used as effective agents for photodynamic therapy with remarkable tumoricidal activity via photodependent cytotoxic activity. The preferential uptake of dyes into cancer but not normal cells is co-operatively mediated by the prevailing activation of a group of organic anion-transporting polypeptides on cancer cell membranes, as well as tumor hypoxia and increased mitochondrial membrane potential in cancer cells. Such mechanistic explorations have greatly advanced the current application and future development of NIRF dyes and their derivatives as anticancer theranostic agents. This review summarizes current knowledge and emerging advances in NIRF dyes, including molecular characterization, photophysical properties, multimodal development and uptake mechanisms, and their growing potential for preclinical and clinical use.

GPRC5A overexpression predicted advanced biological behaviors and poor prognosis in patients with gastric cancer

G protein-coupled receptor, family C, group 5, member A (GPRC5A) had received attentions for its role in carcinogenesis and prognostic values in several types of cancer. However, the functional roles of GPRC5A in gastric cancer (GC) had never been elucidated. The expression levels of GPRC5A were detected by real-time quantitative reverse transcription PCR and Western blot in GC tissues and adjacent non-tumor tissues. GPRC5A expression in tissue sections of 106 GC samples was evaluated using immunohistochemistry. The staining results were compared with clinicopathological factors and to the prognosis of GC patients. The mRNA and protein expression levels of GPRC5A in gastric cancer tissues were higher than those in adjacent non-tumor tissues. Positive GPRC5A expression was significantly correlated with larger size of primary tumor, diffuse type (Lauren's classification), deeper serosal invasion, and more lymph node metastasis. In addition, Kaplan-Meier curve analysis demonstrated that GC patients with positive GPRC5A expression had poor prognosis than those with negative GPRC5A expression. GPRC5A expression was identified as an independent factor of the overall survival in GC patients by multivariate Cox analysis. Further, the overall survival difference existed between patients with GPRC5A positive and negative groups in GC patients with lymph node metastasis. Our results suggested that elevated levels of GPRC5A played significant roles in GC progression. GPRC5A could serve as a prognostic biomarker of GC.

Relating hepatocellular carcinoma tumor samples and cell lines using gene expression data in translational research

Cancer cell lines are used extensively to study cancer biology and to test hypotheses in translational research. The relevance of cell lines is dependent on how closely they resemble the tumors being studied. Relating tumors and cell lines, and recognizing their similarities and differences are thus very important for translational research. Rapid advances in genomics have led to the generation of large volumes of genomic and transcriptomic data for a diverse set of primary cancer samples, normal tissue samples and cancer cell lines. Hepatocellular Carcinoma (HCC) is one of the most common tumors worldwide, with high occurrence in Asia and sub-Saharan regions. The current effective treatments of HCC remain limited. In this work, we compared the gene expression measurements of 200 HCC tumor samples from The Cancer Genome Atlas and over 1000 cancer cell lines including 25 HCC cancer cell lines from Cancer Cell Line Encyclopedia. We showed that the HCC tumor samples correlate closely with HCC cell lines in comparison to cell lines derived from other tumor types. We further demonstrated that the most commonly used HCC cell lines resemble HCC tumors, while we identified nearly half of the cell lines that do not resemble primary tumors. Interestingly, a substantial number of genes that are critical for disease development or drug response are either expressed at low levels or absent among highly correlated cell lines; additional attention should be paid to these genes in translational research. Our study will be used to guide the selection of HCC cell lines and pinpoint the specific genes that are differentially expressed in either tumors or cell lines.

Repeated-measures implication of hepatocellular carcinoma biomarkers in living donor liver transplantation

Objective

Hepatocellular carcinoma (HCC) and its recurrence are major problems in living donor liver transplantation (LDLT). Several biomarkers have been used to investigate this event. We conducted a prospective controlled study to determine the activities of the basic fibroblast growth factor (FGF-2), survivin, Ki67, endostatin, and vascular endothelial growth factor (VEGF) in different conditions before, early after, and late after LDLT with and without HCC recurrence.

Methods

Fifty patients with virus-related HCC who underwent LDLT were enrolled in this 2-year cross-sectional study. During the study period, recurrent HCC was identified in 9 patients (study group, n = 9) and 41 patients (control group, n = 41) had no recurrence after LDLT. The mean time to HCC recurrence was 587.11 ± 398.64 days (range, 90–1352 days). Microvascular invasion (MVI) was found in 66.7% (6/9) of the recipients, as determined on pathological examination. The serum biomarkers were investigated by using enzyme-linked immunosorbent assay at the different LDLT stages.

Results

The serum levels of the biomarkers significantly correlated with LDLT and HCC recurrence in the repeated-measures analysis (F = 31.676, P = 0.000). Significant differences were observed in the effects of all biomarkers (F = 85.313, P = 0.000) and the time to HCC recurrence after LDLT (F = 3.178, P = 0.046). The biomarkers, ordered by the observed power of the test for HCC recurrence after LDLT, were FGF-2 (1.000) > survivin (0.999) > Ki67 (0.949) > endostatin (0.411) > VEGF (0.305).

Conclusions

Different biomarker activities may be implicated in the pathogenesis of HCC recurrence after LDLT. Oncogenes may not exist in the new graft but may still be present in the peripheral blood. The timing of HCC recurrence and impact of MVI in the explanted liver requires confirmation in larger studies with a longer follow-up.

First Selective Small Molecule Inhibitor of FGFR4 for the Treatment of Hepatocellular Carcinomas with an Activated FGFR4 Signaling Pathway

Aberrant signaling through the fibroblast growth factor 19 (FGF19)/fibroblast growth factor receptor 4 (FGFR 4) signaling complex has been shown to cause hepatocellular carcinoma (HCC) in mice and has been implicated to play a similar role in humans. We have developed BLU9931, a potent and irreversible small-molecule inhibitor of FGFR4, as a targeted therapy to treat patients with HCC whose tumors have an activated FGFR4 signaling pathway. BLU9931 is exquisitely selective for FGFR4 versus other FGFR family members and all other kinases. BLU9931 shows remarkable antitumor activity in mice bearing an HCC tumor xenograft that overexpresses FGF19 due to amplification as well as a liver tumor xenograft that overexpresses FGF19 mRNA but lacks FGF19 amplification. Approximately one third of patients with HCC whose tumors express FGF19 together with FGFR4 and its coreceptor klotho β (KLB) could potentially respond to treatment with an FGFR4 inhibitor. These findings are the first demonstration of a therapeutic strategy that targets a subset of patients with HCC.

SIGNIFICANCE

This article documents the discovery of BLU9931, a novel irreversible kinase inhibitor that specifically targets FGFR4 while sparing all other FGFR paralogs and demonstrates exquisite kinome selectivity. BLU9931 is efficacious in tumors with an intact FGFR4 signaling pathway that includes FGF19, FGFR4, and KLB. BLU9931 is the first FGFR4-selective molecule for the treatment of patients with HCC with aberrant FGFR4 signaling.

Hydroxysafflor yellow A inhibits angiogenesis of hepatocellular carcinoma via blocking ERK/MAPK and NF-κB signaling pathway in H22 tumor-bearing mice

Hydroxysafflor yellow A (HSYA), a flavonoid derived and isolated from traditional Chinese medicine Carthamus tinctorius L., possesses anti-tumor activity. However, its effects on hepatocellular carcinoma (HCC) have not been investigated. The proliferation and metastasis of HCC are dependent on angiogenesis, which also strongly links with several signal transduction pathways associated with cell proliferation and apoptosis. This study aimed to explore the effect of HSYA on vasculogenesis and to determine its molecular mechanism by investigating the expression of ERK/MAPK (p-c-Raf, c-Raf, p-ERK1/2, ERK1/2) and NF-κB (p65, IκB and p-IκB) signaling pathway in H22 tumor-bearing mice. The results showed that HSYA could considerably suppress tumor growth by inhibiting secretion of angiogenesis factors (vascular endothelial growth factor A, basic fibroblast growth factor) and vascular endothelial growth factor receptor1. At the moleculcould block ERK1/2 phosphorylation and then restrain the activation of NF-κB and its nuclear translocation by down-regulating the expression of p65 in the nucleus, up-regulating p65 level in the cytoplasm, inhibiting IκB phosphorylation and cytoplasmic degradation of IκB-α. Finally, we demonstrate that HSYA could suppress mRNA expression levels of cell proliferation-related genes (cyclinD1, c-myc, c-Fos) compared with negative control group. And best of all, HSYA could improve spleen/thymus indexes, which was evaluated as the marker of protective effect on the immune system. Our findings support HSYA as a promising candidate for the prevention and treatment of HCC.

The emerging roles of GPRC5A in diseases

The ‘Retinoic Acid-Inducible G-protein-coupled receptors’ or RAIG are a group comprising the four orphan receptors GPRC5A, GPRC5B, GPRC5C and GPRC5D. As the name implies, their expression is induced by retinoic acid but beyond that very little is known about their function. In recent years, one member, GPRC5A, has been receiving increasing attention as it was shown to play important roles in human cancers. As a matter of fact, dysregulation of GPRC5A has been associated with several cancers including lung cancer, breast cancer, colorectal cancer, and pancreatic cancer. Here we review the current state of knowledge about the heterogeneity and evolution of GPRC5A, its regulation, its molecular functions, and its involvement in human disease.