Sorafenib alone or as combination therapy for growth control of cholangiocarcinoma

Angiopoietin-2 and the Vascular Endothelial Growth Factor Promote Migration and Invasion in Hepatocellular Carcinoma- and Intrahepatic Cholangiocarcinoma-Derived Spheroids

Aggressive hepatocellular carcinoma (HCC) overexpressing Angiopoietin-2 (ANG-2) (a protein linked with angiogenesis, proliferation, and epithelial-mesenchymal transition (EMT)), shares 95% of up-regulated genes and a similar poor prognosis with the proliferative subgroup of intrahepatic cholangiocarcinoma (iCCA). We analyzed the pro-invasive effect of ANG-2 and its regulator vascular endothelial growth factor (VEGF) on HCC and CCA spheroids to uncover posUsible common ways of response. Four cell lines were used: Hep3B and HepG2 (HCC), HuCC-T1 (iCCA), and EGI-1 (extrahepatic CCA). We treated the spheroids with recombinant human (rh) ANG-2 and/or VEGF and then observed the changes at the baseline, after 24 h, and again after 48 h. Proangiogenic stimuli increased migration and invasion capability in HCC- and iCCA-derived spheroids and were associated with a modification in EMT phenotypic markers (a decrease in E-cadherin and an increase in N-cadherin and Vimentin), especially at the migration front. Inhibitors targeting ANG-2 (Trebananib) and the VEGF (Bevacizumab) effectively blocked the migration ability of spheroids that had been stimulated with rh-ANG-2 and rh-VEGF. Overall, our findings highlight the critical role played by ANG-2 and the VEGF in enhancing the ability of HCC- and iCCA-derived spheroids to migrate and invade, which are key processes in cancer progression.

Paracrine Interaction of Cholangiocellular Carcinoma with Cancer-Associated Fibroblasts and Schwann Cells Impact Cell Migration

Although the Mitogen-activated protein kinase (MAPK) pathway is enriched in cholangiocarcinoma (CCA), treatment with the multityrosine kinase-inhibitor Sorafenib is disappointing. While cancer-associated fibroblasts (CAF) are known to contribute to treatment resistance in CCA, knowledge is lacking for Schwann cells (SC). We investigated the impact of stromal cells on CCA cells and whether this is affected by Sorafenib. Immunohistochemistry revealed elevated expression of CAF and SC markers significantly correlating with reduced tumor-free survival. In co-culture with CAF, CCA cells mostly migrated, which could be diminished by Sorafenib, while in SC co-cultures, SC predominantly migrated towards CCA cells, unaffected by Sorafenib. Moreover, increased secretion of pro-inflammatory cytokines MCP-1, CXCL-1, IL-6 and IL-8 was determined in CAF mono- and co-cultures, which could be reduced by Sorafenib. Corresponding to migration results, an increased expression of phospho-AKT was measured in CAF co-cultured HuCCT-1 cells, although was unaffected by Sorafenib. Intriguingly, CAF co-cultured TFK-1 cells showed increased activation of STAT3, JNK, ERK and AKT pathways, which was partly reduced by Sorafenib. This study indicates that CAF and SC differentially impact CCA cells and Sorafenib partially reverts these stroma-mediated effects. These findings contribute to a better understanding of the paracrine interplay of CAF and SC with CCA cells.

Ibuprofen and diclofenac differentially affect cell viability, apoptosis and morphological changes in human cholangiocarcinoma cell lines

Objectives

Cholangiocarcinoma is a malignant biliary epithelial duct neoplasm caused by chronic inflammation after liver fluke infection. It is a major public health concern in the Greater Mekong sub-region in northeast Thailand. Herein, the effects of the non-steroidal anti-inflammatory drugs (NSAIDs) ibuprofen and diclofenac on the cell proliferation activity of the human cholangiocarcinoma cell lines KKU-M139 and KKU-213B were studied.

Methods

Cell viability was assessed with MTT assays. Inverted phase-contrast light microscopy, scanning electron microscopy and transmission electron microscopy were used to investigate the cells’ morphological alterations. Caspase 3/7 and Annexin V/PI were detected with a multimode microplate reader.

Results

Ibuprofen and diclofenac decreased viability in both cell lines, and ibuprofen-treated cells exhibited reversible cell injury. In both KKU-M139 and KKU-213B cell lines, the diclofenac-treated cells had the greatest injury. The cells exhibited features of irreversible cell injury. In addition, caspase 3/7 and Annexin V/PI detection revealed early cell apoptotic characteristics.

Conclusion

These findings suggest that NSAIDs may potentially suppress cell viability. Ibuprofen and diclofenac both induced morphological changes and apoptosis.

Patient-Derived Organoids of Cholangiocarcinoma

Cholangiocarcinoma (CC) is an aggressive malignancy with an inferior prognosis due to limited systemic treatment options. As preclinical models such as CC cell lines are extremely rare, this manuscript reports a protocol of cholangiocarcinoma patient-derived organoid culture as well as a protocol for the transition of 3D organoid lines to 2D cell lines. Tissue samples of non-cancer bile duct and cholangiocarcinoma were obtained during surgical resection. Organoid lines were generated following a standardized protocol. 2D cell lines were generated from established organoid lines following a novel protocol. Subcutaneous and orthotopic patient-derived xenografts were generated from CC organoid lines, histologically examined, and treated using standard CC protocols. Therapeutic responses of organoids and 2D cell lines were examined using standard CC agents. Next-generation exome and RNA sequencing was performed on primary tumors and CC organoid lines. Patient-derived organoids closely recapitulated the original features of the primary tumors on multiple levels. Treatment experiments demonstrated that patient-derived organoids of cholangiocarcinoma and organoid-derived xenografts can be used for the evaluation of novel treatments and may therefore be used in personalized oncology approaches. In summary, this study establishes cholangiocarcinoma organoids and organoid-derived cell lines, thus expanding translational research resources of cholangiocarcinoma.

Evidence of Omics, Immune Infiltration, and Pharmacogenomic for SENP1 in the Pan-Cancer Cohort

Sentrin specific-protease 1 (SENP1) is a protein involved in deSUMOylation that is almost overexpressed in cancer. SENP1 has a determinative role in the activation of transcription programs in the innate immune responses and the development B of and C lymphocytes. We found, SENP1 possibly plays a critical role in immune infiltration and acts as an expression marker in PAAD, ESCA, and THYM. CD4+ T cells, CD8+ T cells, and macrophages were more key-related immune cells, indicating that SENP1 might be introduced as a potential target for cancer immunotherapy. We further showed that dysregulation of SENP1 is powerfully associated with decreased patient survival and clinical stage. Total SENP1 protein also increases in cancer. SENP1 is also controlled by transcription factors (TFs) CREB1, KDM5A, REST, and YY1 that regulates apoptosis, cell cycle, cell proliferation, invasion, tumorigenesis, and metastasis. These TFs were in a positive correlation with SENP1. MiR-138-5p, miR-129-1-3p, and miR-129-2-3p also inhibit tumorigenesis through targeting of SENP1. The SENP1 expression level positively correlated with the expression levels of UBN1, SP3, SAP130, NUP98, NUP153 in 32 tumor types. SENP1 and correlated and binding genes: SAP130, NUP98, and NUP153 activated cell cycle. Consistent with this finding, drug analysis was indicated SENP1 is sensitive to cell cycle, apoptosis, and RTK signaling regulators. In the end, SENP1 and its expression-correlated and functional binding genes were enriched in cell cycle, apoptosis, cellular response to DNA damage stimulus. We found that the cell cycle is the main way for tumorigenesis by SENP1. SENP1 attenuates the effect of inhibitory drugs on the cell cycle. We also introduced effective FDA-Approved drugs that can inhibit SENP1. Therefore in the treatments in which these drugs are used, SENP1 inhibition is a suitable approach. This study supplies a wide analysis of the SENP1 across The Cancer Genome Atlas (CGA) cancer types. These results suggest the potential roles of SENP1 as a biomarker for cancer. Since these drugs and the drugs that cause to resistance are applied to cancer treatment, then these two class drugs can use to inhibition of SENP1.

Current progress in systemic therapy for biliary tract cancers

BACKGROUND

Biliary tract cancers (BTCs) are heterogeneous cancers that include cancers of the bile duct and gallbladder. Although they are relatively uncommon, most patients with BTC are diagnosed at advanced-stage disease with high mortality rates. Recently, systemic therapy options for patients with BTC have evolved. This paper reviews recent advancements in systemic therapy and the results of key clinical trials in BTC.

METHODS

A literature search in PubMed and Google Scholar was performed using keywords related to BTC and systemic therapy. Studies that were presented in major international cancer research conferences were also included.

RESULTS

The evidence shows that adjuvant capecitabine has been associated with a lower relapse rate in early-stage BTC. In unselected patients with advanced BTC, combination chemotherapy is a standard treatment option. However, with a better understanding of the molecular profile of BTC, there has been a shift toward targeted agents in BTC that have shown promising responses. The evolving data also support the evolving role of immunotherapy in patients with deficient DNA mismatch repair or PD-L1-positive BTC.

DISCUSSION

Systemic treatment options for BTC have improved. The future identification of new targets, novel compounds, and predictive markers is a key step toward the use of personalized medicine in BTC.

Tissue-Engineered Bile Ducts for Disease Modeling and Therapy

Recent biotechnical advances in the in vitro culture of cholangiocytes and generation of bioengineered biliary tissue have a high potential for creating biliary tissue to be used for disease modeling, drug screening, and transplantation. For the past few decades, scientists have searched for a source of cholangiocytes, focused on primary cholangiocytes or cholangiocytes derived from hepatocytes or stem cells. At the same time, the development of scaffolds for biliary tissue engineering for transplantation and modeling of cholangiopathies has been explored. In this review, we provide an overview on the current understanding of cholangiocytes sources, the effect of signaling molecules, and transcription factors on cell differentiation, along with the effects of extracellular matrix molecules and scaffolds on bioengineered biliary tissues, and their application in disease modeling and drug screening. Impact statement Over the past few decades, biliary tissue engineering has acquired significant attention, but currently a number of factors hinder this field to eventually generate bioengineered bile ducts that mimic in vivo physiology and are suitable for transplantation. In this review, we present the latest advances with respect to cell source selection, influence of growth factors and scaffolds, and functional characterization, as well as applications in cholangiopathy modeling and drug screening. This review is suited for a broad spectrum of readers, including fundamental liver researchers and clinicians with interest in the current state and application of bile duct engineering and disease modeling.

Regorafenib after failure of gemcitabine and platinum-based chemotherapy for locally advanced/metastatic biliary tumors: REACHIN, a randomized, double-blind, phase II trial

BACKGROUND

There is a high unmet clinical need for treatments of advanced/metastatic biliary tract cancers after progression on first-line chemotherapy. Regorafenib has demonstrated efficacy in some gastrointestinal tumors that progress on standard therapies.

PATIENTS AND METHODS

REACHIN was a multicenter, double-blind, placebo-controlled, randomized phase II study designed to evaluate the safety and efficacy of regorafenib in patients with nonresectable/metastatic biliary tract cancer that progressed after gemcitabine/platinum chemotherapy. Patients were randomly assigned 1 : 1 to best supportive care plus either regorafenib 160 mg once daily 3 weeks on/1 week off or placebo until progression or unacceptable toxicity. No crossover was allowed. The primary objective was progression-free survival (PFS). Secondary objectives were response rate, overall survival, and translational analysis.

RESULTS

Sixty-six patients with intrahepatic (n = 42), perihilar (n = 6), or extrahepatic (n = 9) cholangiocarcinoma, or gallbladder carcinoma (n = 9) were randomized, 33 to each treatment group (33 per group). At a median follow-up of 24 months, all patients had progressed and six patients were alive. Median treatment duration was 11.0 weeks [95% confidence interval (CI): 6.0-15.9] in the regorafenib group and 6.3 weeks (95% CI: 3.9-7.0) in the placebo group (P = 0.002). Fourteen of 33 patients (42%) in the regorafenib group had a dose reduction. Stable disease rates were 74% (95% CI: 59-90) in the regorafenib group and 34% with placebo (95% CI: 18-51; P = 0.002). Median PFS in the regorafenib group was 3.0 months (95% CI: 2.3-4.9) and 1.5 months (95% CI: 1.2-2.0) in the placebo group (hazard ratio 0.49; 95% CI: 0.29-0.81; P = 0.004) and median overall survival was 5.3 months (95% CI: 2.7-10.5) and 5.1 months (95% CI: 3.0-6.4), respectively (P = 0.28). There were no unexpected/new safety signals.

CONCLUSION

Regorafenib significantly improved PFS and tumor control in patients with previously treated metastatic/unresectable biliary tract cancer in the second- or third-line setting.

CLINICAL TRIAL REGISTRATION

The trial is registered in the European Clinical Trials Register database (EudraCT 2012-005626-30) and at ClinicalTrials.gov (NCT02162914).

Causes of hOCT1-Dependent Cholangiocarcinoma Resistance to Sorafenib and Sensitization by Tumor-Selective Gene Therapy

Although the multi-tyrosine kinase inhibitor sorafenib is useful in the treatment of several cancers, cholangiocarcinoma (CCA) is refractory to this drug. Among other mechanisms of chemoresistance, impaired uptake through human organic cation transporter type 1 (hOCT1) (gene SLC22A1) has been suggested. Here we have investigated the events accounting for this phenotypic characteristic and have evaluated the interest of selective gene therapy strategies to overcome this limitation. Gene expression and DNA methylation of SLC22A1 were analyzed using intrahepatic (iCCA) and extrahepatic (eCCA) biopsies (Copenhagen and Salamanca cohorts; n = 132) and The Cancer Genome Atlas (TCGA)-CHOL (n = 36). Decreased hOCT1 mRNA correlated with hypermethylation status of the SLC22A1 promoter. Treatment of CCA cells with decitabine (demethylating agent) or butyrate (histone deacetylase inhibitor) restored hOCT1 expression and increased sorafenib uptake. MicroRNAs able to induce hOCT1 mRNA decay were analyzed in paired samples of TCGA-CHOL (n = 9) and Copenhagen (n = 57) cohorts. Consistent up-regulation in tumor tissue was found for miR-141 and miR-330. High proportion of aberrant hOCT1 mRNA splicing in CCA was also seen. Lentiviral-mediated transduction of eCCA (EGI-1 and TFK-1) and iCCA (HuCCT1) cells with hOCT1 enhanced sorafenib uptake and cytotoxic effects. In chemically induced CCA in rats, reduced rOct1 expression was accompanied by impaired sorafenib uptake. In xenograft models of eCCA cells implanted in mouse liver, poor response to sorafenib was observed. However, tumor growth was markedly reduced by cotreatment with sorafenib and adenoviral vectors encoding hOCT1 under the control of the BIRC5 promoter, a gene highly up-regulated in CCA. Conclusion: The reason for impaired hOCT1-mediated sorafenib uptake by CCA is multifactorial. Gene therapy capable of selectively inducing hOCT1 in tumor cells can be considered a potentially useful chemosensitization strategy to improve the response of CCA to sorafenib.

Advances in the Diagnosis and Treatment of Patients with Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is an aggressive biliary tract cancer (BTC) that arises from the biliary tract epithelium distal to the secondary biliary radicals. Over the past decade, significant advances have been made in the diagnosis, staging, and treatment of ICC. Emerging data have highlighted the importance of lymphadenectomy for elucidating patient prognosis as well as the at-risk nodal basins based on tumor location (de Jong et al. in J Clin Oncol 29(23):3140-3145, 2011). Several large randomized controlled trials have recently been published clarifying the role of adjuvant therapy for BTCs (Cloyd and Pawlik in J Oncol Pract 14(12):723-724, 2018). In addition, the molecular understanding of ICC pathogenesis has increased over time, leading to new potential molecular biomarkers and opening opportunities for novel targeted and immunologic therapies (Rizvi et al. in Nat Rev Clin Oncol 15(2):95-111, 2018). These recent advances serve to only improve our understanding of the optimal multidisciplinary treatment of this difficult disease.

The synergistic antitumor effect of Huaier combined with 5-Florouracil in human cholangiocarcinoma cells

BACKGROUND

5-Florouracil (5-FU) is a commonly used chemotherapeutic drug for cholangiocarcinoma, whereas it has unsatisfactory effect, and patients often have chemo-resistance to it. The combination of chemotherapeutic agents and traditional Chinese medicine has already exhibited a promising application in oncotherapy. Huaier extract (Huaier) has been used in clinical practice widely, exhibiting good anti-tumor effect. This paper aims to investigate the possibility of combination 5-FU and Huaier as a treatment for cholangiocarcinoma.

METHODS

A series of experiments were performed on the Huh28 cells in vitro, which involved cell proliferation, colony formation, apoptosis, cell cycle, migratory and invasive tests. Besides, western blots were also performed to examine the potential mechanism of 5-FU.

RESULTS

The combination effect (antagonism, synergy or additive) was assessed using Chou-Talalay method. Using the CCK-8 and Colony formation assay, the anti-proliferation effect of 5-FU combined with Huaier was observed. Apoptosis inducing and cell cycle arrest effect of the combination of two drugs were assessed by flow cytometry. To determine the combined treatment on cell immigration and invasion ability, wound healing and Transwell assay were performed. The above experiment results suggest that the combined 5-FU and Huaier, compared with treatment using either drug alone, exhibited stronger effects in anti-proliferation, cycle arrest, apoptosis-induced and anti-metastasis. Further, western blot results reveal that the inhibition of STAT3 and its target genes (e.g. Ki67, Cyclin D1, Bcl-2 and MMP-2) might be set as the potential therapeutic targets. Besides, the inhibition of combination treatment in proteins expression associated with proliferation, apoptosis, cell cycle and metastasis was consistent with that of previous phenotypic experiments.

CONCLUSIONS

Huaier combined with 5-FU exhibited a synergistic anti-tumor effect in Huh28 cell. Furthermore, the mechanisms might be associated with the activation and translocation of STAT3, as well as its downstream genes.

Increased expression of SLC46A3 to oppose the progression of hepatocellular carcinoma and its effect on sorafenib therapy

Hepatocellular carcinoma (HCC) prognosis remains dismal due to postsurgical recurrence and distant metastasis. Therefore, novel prognostic biomarkers and therapeutic targets for HCC therapy are urgently needed to improve the survival of liver cancer patients. Our evidence suggests that SLC46A3 (the gene solute carrier family 46 (sodium phosphate), member 3) is a member of the SLC46 family and has a potential role in the progression and treatment of HCC. The objective of the present study was to estimate the expression pattern and biological function of SLC46A3 in the progression of HCC, which may serve as a promising biomarker for diagnosis and therapy. In order to determine the expression pattern of SLC46A3 in HCC, several public HCC databases and tissue chips were used to examine 129 sets of primary HCC and non-tumor adjacent tissues from patients who had undergone surgery. The expression of SLC46A3 in 80 sets of HCC and non-tumor adjacent tissues were then compared by RT-PCR and Western Blot. The proliferation, invasion, migration and sphere-forming abilities of SLC46A3 knock-down and overexpressing cell lines were evaluated and the expression of related molecules in the epithelial mesenchymal transition (EMT) were detected by RT-PCR, western blot and immunofluorescence assay. The IC₅₀ value was used to evaluate the effect of SLC46A3 on sorafenib resistance. A lung metastasis model of mice HCC was constructed to test the potential effect of SLC46A3 on cancer metastasis and a subcutaneous xenografted tumor mice model was designed to verify the effect of SLC46A3 on the resistance of HCC cell lines to sorafenib. The expression of SLC46A3 was down-regulated in 83.2% of human HCC tissues compared to non-tumor adjacent tissues. Tumors that expressed low levels of SLC46A3 had more aggressive phenotypes, and patients with these tumors had shorter survival times after surgery compared to patients whose tumors expressed high levels of SLC46A3. Hepatocellular carcinoma cell lines that stably overexpressed SLC46A3 inhibited the levels of migration and invasion compared with control HCC cells, and formed smaller xenograft tumors with more metastases in mice compared with HCC cells that did not overexpress SLC46A3. In addition, overexpression of SLC46A3 obviously inhibited epithelial-to-mesenchymal transition-activating transcription factors such as N-cadherin and Vimentin. Furthermore, descended of IC₅₀ showed that overexpressed SLC46A3 could reduce sorafenib resistance and improve drug response in vivo and in vitro. In conclusion, increased expression of SLC46A3 could favor a better clinical prognosis for patients with HCC, ameliorate sorafenib resistance, and improve drug response. SLC46A3 might serve as a potential prognostic biomarker and therapeutic target in HCC.

Biliary tract cancers: current knowledge, clinical candidates and future challenges

Biliary tract cancers (BTCs) are rare with poor prognosis. Due to the advent of genomic sequencing, new data have emerged regarding the molecular makeup of this disease. To add to the complexity, various subtypes also harbor a varied genetic composition. The commonly mutated genes associated with this cancer are KRAS, EGFR, IDH, FGFR and BAP1. Various clinical studies are looking at targeting these genetic mutations. Another therapeutic area of note is the potential for the use of immunotherapy in patients with BTC. Although BTC may be a result of chronic inflammation, this does not necessarily translate into increased immunogenicity. This literature review discusses the diverse molecular and immune-related pathways in patients with BTC and their potential therapeutic implications.

Implementation of comprehensive rehabilitation therapy in postoperative care of patients with cholangiocarcinoma and its impact on patients' quality of life

Implementation of comprehensive rehabilitation therapy in postoperative care of patients with cholangiocarcinoma was studied to explore its impact on patients' quality of life. Two hundred and nineteen patients with cholangiocarcinoma who underwent surgery in Yidu Central Hospital of Weifang from April 2014 to June 2017 were selected as study subjects. Of these patients, 116 received comprehensive rehabilitation therapy, in addition to chemotherapy, after surgery and were assigned to the experimental group. The remaining 103 patients received routine treatment after surgery and were assigned to the control group. Under the guidance of experts, patients in the experimental group carried out multiple comprehensive rehabilitation activities, such as exercises on general physical function, adjustment of psychological state and recovery of social family function. The outcome after 1 month of treatment was evaluated for the two groups according to the RECIST 1.1 guidelines. Nutritional status of patients before surgery, at 1 day and at 1 month after surgery was measured according to the Nutritional Risk Screening endorsed by the European Society for Clinical Nutrition and Metabolism (ESPEN). The quality of life at 1 month after surgery was assessed based on the QLQ-C30 quality of life questionnaire. The negative emotions that patients experienced at 1 month after surgery were assessed using the self-rating anxiety scale (SAS) and the self-rating depression scale (SDS). The response rate in the experimental group was 76.72%, which was significantly higher than 46.60% in the control group (P<0.05). At 1 month after surgery, the nutritional status and quality of life, as well as SAS/SDS scores, were significantly better in the experimental group than in the control group, and the differences were statistically significant (P<0.05). In clinical anticancer treatment, synergistic implementation of comprehensive rehabilitation therapy can improve patients' psychological health status, nutritional status and the overall quality of life, and reduce the impact of negative emotions on the physical state.

Novel zinc‑ and silicon‑phthalocyanines as photosensitizers for photodynamic therapy of cholangiocarcinoma

Photodynamic therapy (PDT) has emerged as an effective and minimally invasive cancer treatment modality. In the present study, two novel phthalocyanines, tetra‑triethyleneoxysulfonyl substituted zinc phthalocyanine (ZnPc) and dihydroxy‑2,9(10),16(17),23(24)‑tetrakis(4,7,10‑trioxaundecan‑1‑sulfonyl) silicon phthalocyanine (Pc32), were investigated as photosensitizers (PS) for PDT of cholangiocarcinoma (CC). ZnPc showed a pronounced dose‑dependent and predominantly cytoplasmic accumulation in EGI‑1 and TFK‑1 CC cell lines. Pc32 also accumulated in the CC cells, but this was less pronounced. Without photoactivation, the PS did not exhibit any antiproliferative or cytotoxic effects. Upon photoactivation, ZnPc induced the formation of reactive oxygen species (ROS) and immediate phototoxicity, leading to a dose‑dependent decrease in cell proliferation, and an induction of mitochondria‑driven apoptosis and cell cycle arrest of EGI‑1 and TFK‑1 cells. Although photoactivated Pc32 also induced ROS formation in the two cell lines, the extent was less marked, compared with that induced by ZnPc‑PDT, and pronounced antipoliferative effects occurred only in the less differentiated EGI‑1 cells, whereas the more differentiated TFK‑1 cells did not show sustained growth inhibition upon Pc32‑PDT induction. In vivo examinations on the antiangiogenic potency of the novel PS were performed using chorioallantoic membrane (CAM) assays, which revealed reduced angiogenic sprouting with a concomitant increase in nonperfused regions and degeneration of the vascular network of the CAM following induction with ZnPc‑PDT only. The study demonstrated the pronounced antiproliferative and antiangiogenic potency of ZnPc as a novel PS for PDT, meriting further elucidation as a promising PS for the photodynamic treatment of CC.

Synergistic Effect of Forbesione From Garcinia hanburyi in Combination with 5-Fluorouracil on Cholangiocarcinoma

Background: Chemotherapy for advanced cholangiocarcinoma (CCA) is largely ineffective; thus innovative combinations of chemotherapeutic agents and natural compounds represent a promising strategy. This study aimed to investigate the synergistic effects of forbesione combined with 5-fluorouracil (5-FU) in hamster cholangiocarcinoma (Ham-1) cells both in vitro and in vivo. The anti-tumor effects of 5-FU combined with forbesione in vitro were determined using the Sulforhodamine B (SRB) assay and the effects in vivo were assessed in transplanted Ham-1 allograph models. Using ethidium bromide/acridine orange (EB/AO) staining, the morphological changes of apoptotic cells was investigated. The expressions of apoptosis-related molecules after combined treatment with forbesione and 5-FU were determined using real-time RT-PCR and western blot analysis. Forbesione or 5-FU alone inhibited proliferation of Ham-1 cells in a dose-dependent manner and their combination showed a synergistic proliferation inhibitory effect in vitro. In vivo studies, forbesione in combination with 5-FU exhibited greater inhibition of the tumor in the hamster model compared with treatment using either drug alone. Forbesione combined with 5-FU exerted stronger apoptotic induction in Ham-1 cells than did single drug treatment. The combination of drugs strongly suppressed the expression of B-cell lymphoma 2 (Bcl-2) and procaspase-3 while enhancing the expression of p53, Bcl-2-associated X protein (Bax), apoptotic protease activating factor-1 (Apaf-1), caspase-9 and caspase-3, compared with single drug treatments. These results explained the decreased expression of cytokeratin 19 (CK19) positive cells and proliferation cell nuclear antigen (PCNA) positive cells in Ham-1 cell tumor tissues of the treated hamsters. There was no apparent systemic toxicity observed in the treated animals compared with the control groups. Forbesione combined with 5-FU strongly induced apoptosis in Ham-1 cells. The growth inhibitory effect of combined treatment using these two drugs was much greater than treatment with either drug alone, both in vitro and in vivo.

Inhibitory Effect of Aspirin on Cholangiocarcinoma Cells

Aspirin and other non-steroidal anti-inflammatory drugs reduce the risk of cancer due to their anti-proliferative and apoptotic effects, which are the important mechanisms for their anti-tumor activity. Here, the effect of aspirin on human cholangiocarcinoma cells (KKU-214) and the underlying mechanisms of its action were explored. Cell proliferation was measured by sulforhodamine B (SRB) assay, while cell cycle distribution and apoptosis were determined by flow cytometry. Western blotting was used to explore protein expression underlying molecular mechanisms of anti-cancer treatment of aspirin. Aspirin reduced cell proliferation in a dose- and time-dependent manner, and altered the cell cycle phase distribution of KKU-214 cells by increasing the proportion of cells in the G0/G1 phase and reducing the proportion in the S and G2/M phases. Consistent with its effect on the cell cycle, aspirin also reduced the expression of cyclin D1 and cyclin-dependent kinase 4 (Cdk-4), which are important for G0/G1 cell cycle progression. Treatment with aspirin led to increased induction of apoptosis in a dose-dependent manner. Further analysis of the mechanism underlying the effect of this drug showed that aspirin induced the expression of the tumor-suppressor protein p53 while inhibiting the anti-apoptotic protein B-cell lymphoma-2 (Bcl-2). Correspondingly, the activation of caspase-9 and -3 was also increased. These findings suggest that aspirin causes cell cycle arrest and apoptosis, both of which could contribute to its anti-proliferative effect.

Sumoylation in p27kip1 via RanBP2 promotes cancer cell growth in cholangiocarcinoma cell line QBC939

BACKGROUND

Cholangiocarcinoma is one of the deadly disease with poor 5-year survival and poor response to conventional therapies. Previously, we found that p27kip1 nuclear-cytoplasmic translocation confers proliferation potential to cholangiocarcinoma cell line QBC939 and this process is mediated by crm-1. However, no other post-transcriptional regulation was found in this process including sumoylation in cholangiocarcinoma.

RESULTS

In this study, we explored the role of sumoylation in the nuclear-cytoplasmic translocation of p27kip1 and its involvement of QBC939 cells' proliferation. First, we identified K73 as the sumoylation site in p27kip1. By utilizing plasmid flag-p27kip1, HA-RanBP2, GST-RanBP2 and His-p27kip1 and immunoprecipitation assay, we validated that p27kip1 can serve as the sumoylation target of RanBP2 in QBC939. Furthermore, we confirmed crm-1's role in promoting nuclear-cytoplasmic translocation of p27kip1 and found that RanBP2's function relies on crm-1. However, K73R mutated p27kip1 can't be identified by crm-1 or RanBP2 in p27kip1 translocation process, suggesting sumoylation of p27kip1 via K73 site is necessary in this process by RanBP2 and crm-1. Phenotypically, the overexpression of either RanBP2 or crm-1 can partially rescue the anti-proliferative effect brought by p27kip1 overexpression in both the MTS and EdU assay. For the first time, we identified and validated the K73 sumoylation site in p27kip1, which is critical to RanBP2 and crm-1 in p27kip1 nuclear-cytoplasmic translocation process.

CONCLUSION

Taken together, targeted inhibition of sumoylation of p27kip1 may serve as a potentially potent therapeutic target in the eradication of cholangiocarcinoma development and relapses.

Novel zinc phthalocyanine as a promising photosensitizer for photodynamic treatment of esophageal cancer

Photodynamic therapy (PDT) has gathered much attention in the field of cancer treatment and is increasingly used as an alternative solution for esophageal cancer therapy. However, there is a constant need for improving the effectiveness and tolerability of the applied photosensitizers (PS). Here, we propose tetra-triethyleneoxysulfonyl substituted zinc phthalocyanine (ZnPc) as a promising PS for photodynamic treatment of esophageal cancer. ZnPc-induced phototoxicity was studied in two human esophageal cancer cell lines: OE-33 (adenocarcinoma) and Kyse-140 (squamous cell carcinoma). In vitro studies focused on the uptake and intracellular distribution of the novel ZnPc as well as on its growth inhibitory potential, reactive oxygen species (ROS) formation and the induction of apoptosis. The chicken chorioallantoic membrane assay (CAM assay) and studies on native Wistar rats were employed to determine the antineoplastic and antiangiogenic activity of ZnPc-PDT as well as the tolerability and safety of non-photoactivated ZnPc in vivo. ZnPc was taken up by cancer cells in a dose- and time-dependent manner and showed a homogeneous cytoplasmic distribution. Photoactivation of ZnPc-loaded (1-10 µM) cells led to a dose-dependent growth inhibition of esophageal adenocarcinoma and squamous cell carcinoma cells of >90%. The antiproliferative effect was based on ROS-induced cytotoxicity and the induction of mitochondria-driven apoptosis. In vivo studies on esophageal tumor plaques grown on the CAM revealed pronounced antiangiogenic and antineoplastic effects. ZnPc-PDT caused long-lasting changes in the vascular architecture and a marked reduction of tumor feeding blood vessels. Animal studies confirmed the good tolerability and systemic safety of ZnPc, as no changes in immunological, behavioral and organic parameters could be detected upon treatment with the non-photoactivated ZnPc. Our findings show the extraordinary photoactive potential of the novel ZnPc as a photosensitizer for PDT of esophageal cancer.

CRM-1 knockdown inhibits extrahepatic cholangiocarcinoma tumor growth by blocking the nuclear export of p27Kip1

Cholangiocarcinoma is a deadly disease which responds poorly to surgery and conventional chemotherapy or radiotherapy. Early diagnosis is difficult due to the anatomical and biological characteristics of cholangiocarcinoma. Cyclin-dependent kinase inhibitor 1B (p27Kip1) is a cyclin‑dependent kinase inhibitor and in the present study, we found that p27Kip1 expression was suppressed in the nucleus and increased in the cytoplasm in 53 samples of cholangiocarcinoma from patients with highly malignant tumors (poorly-differentiated and tumor-node-metastsis (TNM) stage III-IV) compared with that in samples from 10 patients with chronic cholangitis. The expression of phosphorylated (p-)p27Kip1 (Ser10), one of the phosphorylated forms of p27Kip1, was increased in the patient samples with increasing malignancy and clinical stage. Coincidentally, chromosome region maintenance 1 (CRM-1; also referred to as exportin 1 or Xpo1), a critical protein responsible for protein translocation from the nucleus to the cytoplasm, was also overexpressed in the tumor samples which were poorly differentiated and of a higher clinical stage. Through specific short hairpin RNA (shRNA)-mediated knockdown of CRM-1 in the cholangiocarcinoma cell line QBC939, we identified an elevation of cytoplasmic p27Kip1 and a decrease of nuclear p27Kip1. Furthermore, the viability and colony formation ability of QBC939 cells was largely reduced with G1 arrest. Consistent with the findings of the in vitro experiments, in a xenograft mouse model, the tumors formed in the CRM-1 knockdown group were markedly smaller and weighed less than those in the control group in vivo. Taken together, these findings demonstrated that the interplay between CRM-1 and p27Kip1 may provide potentially potent biomarkers and functional targets for the development of future cholangiocarcinoma treatments.

New Approach for Treatment of Primary Liver Tumors: The Role of Quercetin

Hepatocellular carcinoma (HCC) is the most common primary liver tumor (PLT), with cholangiocarcinoma (CC) being the second most frequent. Glucose transporter 1 (GLUT-1) expression is increased in PLTs and therefore it is suggested as a therapeutic target. Flavonoids, like quercetin, are GLUT-1 competitive inhibitors and may be considered as potential therapeutic agents for PLTs. The objective of this study was evaluation of quercetin anticancer activity in three human HCC cell lines (HepG2, HuH7, and Hep3B2.1-7) and in a human CC cell line (TFK-1). The possible synergistic effect between quercetin and sorafenib, a nonspecific multikinase inhibitor used in clinical practice in patients with advanced HCC, was also evaluated. It was found that in all the cell lines, quercetin induced inhibition of the metabolic activity and cell death by apoptosis, followed by increase in BAX/BCL-2 ratio. Treatment with quercetin caused DNA damage in HepG2, Hep3B2.1-7, and TFK-1 cell lines. The effect of quercetin appears to be independent of P53. Incubation with quercetin induced an increase in GLUT-1 membrane expression and a consequent reduction in the cytoplasmic fraction, observed as a decrease in (18)F-FDG uptake, indicating a GLUT-1 competitive inhibition. The occurrence of synergy when sorafenib and quercetin were added simultaneously to HCC cell lines was noticed. Thus, the use of quercetin seems to be a promising approach for PLTs through GLUT-1 competitive inhibition.

Cholangiocarcinoma: from molecular biology to treatment

Cholangiocarcinoma is a rare tumor originating in the bile ducts, which, according to their anatomical location, is classified as intrahepatic, extrahepatic and hilar. Nevertheless, incidence rates have increased markedly in recent decades. With respect to tumor biology, several genetic alterations correlated with resistance to chemotherapy and radiotherapy have been identified. Here, we highlight changes in KRAS and TP53 genes that are normally associated with a more aggressive phenotype. Also IL-6 and some proteins of the BCL-2 family appear to be involved in the resistance that the cholangiocarcinoma presents toward conventional therapies. With regard to diagnosis, tumor markers most commonly used are CEA and CA 19-9, and although its use isolated appears controversial, their combined value has been increasingly advocated. In imaging terms, various methods are needed, such as abdominal ultrasound, computed tomography and cholangiopancreatography. Regarding therapy, surgical modalities are the only ones that offer chance of cure; however, due to late diagnosis, most patients cannot take advantage of them. Thus, the majority of patients are directed to other therapeutic modalities like chemotherapy, which, in this context, assumes a purely palliative role. Thus, it becomes urgent to investigate new therapeutic options for this highly aggressive type of tumor.

Combinatorial anticancer effects of curcumin and sorafenib towards thyroid cancer cells via PI3K/Akt and ERK pathways

The objective of this study was to examine the in vitro combinatorial anticancer effects of curcumin and sorafenib towards thyroid cancer cells FTC133 using a MTT cytotoxicity assay, and to test whether the mechanism involves induction of apoptosis. The present results demonstrated that curcumin at 15-25 μM dose-dependently suppressed the proliferation of FTC133. Combined treatment (curcumin (25 μM) and sorafenib (2 μM)) resulted in a reduction in cell colony formation and significantly decreased the invasion and migration of FTC133 cells compared with that treated with individual drugs. Western blot showed that the levels of p-ERK and p-Akt proteins were significantly reduced (p < 0.01) in the medicine-treated FTC133 cells. The curcumin was found to dose-dependently inhibit the apoptosis of FTC133 cells possibly via PI3K/Akt and ERK pathways. There is a synergetic antitumour effect between curcumin and sorafenib.

FTY720 (Fingolimod) sensitizes hepatocellular carcinoma cells to sorafenib-mediated cytotoxicity

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide. The multityrosine kinase inhibitor sorafenib is used in the therapy of advanced disease. However, the effects of sorafenib are limited, and combination treatments aiming at improved survival are encouraged. The sphingosine analog FTY720 (Fingolimod), which is approved for treatment of multiple sclerosis, has shown tumor suppressive effects in cell lines and animal models of HCC. In the present study, we combined sorafenib with FTY720 in order to sensitize the HCC cell lines Huh7 and HepG2 to sorafenib treatment. Using the XTT assay we show that noncytotoxic doses of FTY720 synergistically enhanced the decrease in viability caused by treatment of both cell lines with increasing doses of sorafenib. Further studies in Huh7 revealed that combined treatment with FTY720 and sorafenib resulted in G1 arrest and enhanced cell death measured using flow cytometry analysis of cells labeled with propidium iodide (PI)/Annexin-V and PI and 4′,6-diamidino-2-phenylindole-staining of nuclei. In addition, signs of both caspase-dependent and – independent apoptosis were observed, as cotreatment with FTY720 and sorafenib caused cytochrome c release and poly-ADP ribose polymerase-cleavage as well as translocation of Apoptosis-inducing factor into the cytosol. We also detected features of autophagy blockage, as the protein levels of LC3-II and p62 were affected by combined treatment with FTY720 and sorafenib. Together, our results suggest that FTY720 sensitizes HCC cells to cytotoxic effects induced by treatment with sorafenib alone. These findings warrant further investigations of combined treatment with sorafenib and FTY720 in vivo in order to develop more effective treatment of HCC.

A randomized, multicenter, phase II study of vandetanib monotherapy versus vandetanib in combination with gemcitabine versus gemcitabine plus placebo in subjects with advanced biliary tract cancer: the VanGogh study

BACKGROUND

The management of biliary tract cancers (BTCs) is complex due to limited data on the optimal therapeutic approach. This phase II multicenter study evaluated the efficacy and tolerability of vandetanib monotherapy compared with vandetanib plus gemcitabine or gemcitabine plus placebo in patients with advanced BTC.

PATIENTS AND METHODS

Patients were randomized in a 1 : 1 : 1 ratio to three treatment groups: vandetanib 300 mg monotherapy (V), vandetanib 100 mg plus gemcitabine (V/G), gemcitabine plus placebo (G/P). Vandetanib (300 mg or 100 mg) or placebo was given in single oral daily doses. Gemcitabine 1000 mg/m(2) was i.v. infused on day 1 and day 8 of each 21-day cycle. The primary end point was progression-free survival (PFS). Secondary end points were: objective response rate (ORR), disease control rate, overall survival, duration of response, performance status and safety outcomes.

RESULTS

A total of 173 patients (mean age 63.6 years) were recruited at 19 centers across Italy. Median (95% confidence intervals) PFS (days) were 105 (72-155), 114 (91-193) and 148 (71-225), respectively, for the V, V/G and G/P treatment groups, with no statistical difference among them (P = 0.18). No statistical difference between treatments was observed for secondary end points, except ORR, which slightly favored the V/G combination over other treatments. The proportion of patients reporting adverse events (AEs) was similar for the three groups (96.6% in V arm, 91.4% in the V/G arm and 89.3% in the G/P arm).

CONCLUSIONS

Vandetanib treatment did not improve PFS in patients with advanced BTC. The safety profile of vandetanib did not show any additional AEs or worsening of already known AEs.

CLINICAL TRIAL NUMBER

NCT00753675.

Gemcitabine plus sorafenib versus gemcitabine alone in advanced biliary tract cancer: a double-blind placebo-controlled multicentre phase II AIO study with biomarker and serum programme

BACKGROUND

Since sorafenib has shown activity in different tumour types and gemcitabine regimens improved the outcome for biliary tract cancer (BTC) patients, we evaluated first-line gemcitabine plus sorafenib in a double-blind phase II study.

PATIENTS AND METHODS

102 unresectable or metastatic BTC patients with histologically proven adenocarcinoma of gallbladder or intrahepatic bile ducts, Eastern Cooperative Oncology Group (ECOG) 0-2 were randomised to gemcitabine (1000 mg/m2 once weekly, first 7-weeks+1-week rest followed by once 3-weeks+1-week rest) plus sorafenib (400 mg twice daily) or placebo. Treatment continued until progression or unacceptable toxicity. Tumour samples were prospectively stained for sorafenib targets and potential biomarkers. Serum samples (first two cycles) were measured for vascular endothelial growth factors (VEGFs), vascular endothelial growth factor receptor 2 (VEGFR-2) and stromal cell-derived factor 1 (SDF1)α by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Gemcitabine plus sorafenib was generally well tolerated. Four and three patients achieved partial responses in the sorafenib and placebo groups, respectively. There was no difference in the primary end-point, median progression-free survival (PFS) for gemcitabine plus sorafenib versus gemcitabine plus placebo (3.0 versus 4.9 months, P=0.859), and no difference for median overall survival (OS) (8.4 versus 11.2 months, P=0.775). Patients with liver metastasis after resection of primary BTC survived longer with sorafenib (P=0.019) compared to placebo. Patients who developed hand-foot syndrome (HFS) showed longer PFS and OS than patients without HFS. Two sorafenib targets, VEGFR-2 and c-kit, were not expressed in BTC samples. VEGFR-3 and Hif1α were associated with lymph node metastases and T stage. Absence of PDGFRβ expression correlated with longer PFS.

CONCLUSION

The addition of sorafenib to gemcitabine did not demonstrate improved efficacy in advanced BTC patients. Biomarker subgroup analysis suggested that some patients might benefit from combined treatment.

Update on the management of cholangiocarcinoma

Cholangiocarcinoma (CC) is a rare cancer arising from the epithelium of the biliary tree, anywhere from the small peripheral hepatic ducts to the distal common bile duct. Classification systems for CC typically group tumours by anatomical location into intrahepatic, hilar or extrahepatic subtypes. Surgical resection or liver transplantation remains the only curative therapy for CC, but up to 80% of patients present with advanced, irresectable disease. Unresectable CC remains resistant to many chemotherapeutic agents, although gemcitabine, particularly in combination with other agents, has been shown to improve overall survival. Ongoing investigation of biological agents has also yielded some promising results. Several novel interventional and endoscopic techniques for the diagnosis and management of non-operable CC have been developed: initial results show improvements in symptoms and progression-free survival, but further randomised studies are required to establish their role in the management of CC.

Multimodal imaging of tumor response to sorafenib combined with radiation therapy: comparison between diffusion-weighted MRI, choline spectroscopy and 18F-FLT PET imaging

The purpose of this study was to determine the value of different imaging modalities, that is, magnetic resonance imaging/spectroscopy (MRI/MRS) and positron emission tomography (PET), to assess early tumor response to sorafenib with or without radiotherapy. Diffusion-weighted (DW)-MRI, choline (1)H MRS at 11.7 T, and (18)F-FLT PET imaging were used to image fibrosarcoma (FSaII) tumor-bearing mice over time. The imaging markers were compared with apoptosis cell death and cell proliferation measurements assessed by histology. Anti-proliferative effects of sorafenib were evidenced by (1)H MRS and (18)F-FLT PET after 2 days of treatment with sorafenib, with no additional effect of the combination with radiation therapy, results that are in agreement with Ki67 staining. Apparent diffusion coefficient calculated using DW-MRI was not modified after 2 days of treatment with sorafenib, but showed significant increase 24 h after 2 days of sorafenib treatment combined with consecutive irradiation. The three imaging markers were able to show early tumor response as soon as 24 h after treatment initiation, with choline MRS and (18)F-FLT being sensitive to sorafenib in monotherapy as well as in combined therapy with irradiation, whereas DW-MRI was only sensitive to the combination of sorafenib with radiotherapy.

Expression of SLC22A1 variants may affect the response of hepatocellular carcinoma and cholangiocarcinoma to sorafenib

Reduced drug uptake is an important mechanism of chemoresistance. Down-regulation of SLC22A1 encoding the organic cation transporter-1 (OCT1) may affect the response of hepatocellular carcinoma (HCC) and cholangiocarcinoma (CGC) to sorafenib, a cationic drug. Here we investigated whether SLC22A1 variants may contribute to sorafenib chemoresistance. Complete sequencing and selective variant identification were carried out to detect single nucleotide polymorphisms (SNPs) in SLC22A1 complementary DNA (cDNA). In HCC and CGC biopsies, in addition to previously described variants, two novel alternative spliced variants and three SNPs were identified. To study their functional consequences, these variants were mimicked by directed mutagenesis and expressed in HCC (Alexander and SK-Hep-1) and CGC (TFK1) cells. The two novel described variants, R61S fs*10 and C88A fs*16, encoded truncated proteins unable to reach the plasma membrane. Both variants abolished OCT1-mediated uptake of tetraethylammonium, a typical OCT1 substrate, and were not able to induce sorafenib sensitivity. In cells expressing functional OCT1 variants, OCT1 inhibition with quinine prevented sorafenib-induced toxicity. Expression of OCT1 variants in Xenopus laevis oocytes and determination of quinine-sensitive sorafenib uptake by high-performance liquid chromatography-dual mass spectrometry confirmed that OCT1 is able to transport sorafenib and that R61S fs*10 and C88A fs*16 abolish this ability. Screening of these SNPs in 23 HCC and 15 CGC biopsies revealed that R61S fs*10 was present in both HCC (17%) and CGC (13%), whereas C88A fs*16 was only found in HCC (17%). Considering all SLC22A1 variants, at least one inactivating SNP was found in 48% HCC and 40% CGC.

CONCLUSION

Development of HCC and CGC is accompanied by the appearance of aberrant OCT1 variants that, together with decreased OCT1 expression, may dramatically affect the ability of sorafenib to reach active intracellular concentrations in these tumors.

Second-line therapy in advanced biliary tract cancer: what should be the standard?

Biliary tract cancer is a rare malignant tumor. Accordingly, to perform prospective and randomized trials is difficult and the knowledge of its natural history and optimal management remains limited. Chemotherapy is commonly used to improve the outcome and to delay tumor progression in advanced disease. Only recently, cisplatin-gemcitabine combination was identified as the new standard first-line therapy. Despite the outcome improvement, disease progression is a constant and approximately half of patients failing upfront treatment maintain a good performance status and are willing to undergo further treatment. No standard salvage chemotherapy regimen has been identified yet. Experiences of salvage therapy in advanced biliary tract cancer are sparse and yielded disappointing results. Well designed multi-institutional randomized trials are warranted to clarify the role and the activity of a second-line therapy.

Anti-proliferative actions of N'-desmethylsorafenib in human breast cancer cells

The multi-kinase inhibitor sorafenib is used for the treatment of renal and hepatic carcinomas and is undergoing evaluation for treatment of breast cancer in combination with other agents. Cytochrome P450 (CYP) 3A4 converts sorafenib to multiple metabolites that have been detected in patient plasma. However, recent clinical findings suggest that combination therapy may elicit inhibitory pharmacokinetic interactions involving sorafenib that increase toxicity. While sorafenib N-oxide is an active metabolite, information on the anti-tumor actions of other metabolites is unavailable. The present study evaluated the actions of sorafenib and its five major metabolites in human breast cancer cell lines. All agents, with the exception of N'-hydroxymethylsorafenib N-oxide, decreased ATP formation in four breast cancer cell lines (MDA-MB-231, MDA-MB-468, MCF-7 and T-47D). Prolonged treatment of MDA-MB-231 cells with N'-desmethylsorafenib, N'-desmethylsorafenib N-oxide and sorafenib (10 μM, 72 h) produced small increases in caspase-3 activity to 128-139% of control. Sorafenib and its metabolites, again with the exception of N'-hydroxymethylsorafenib N-oxide, impaired MEK/ERK signaling in MDA-MB-231 cells and modulated the expression of cyclin D1 and myeloid cell leukemia sequence-1, which regulate cell viability. When coadministered with doxorubicin (0.5 or 1 μM), sorafenib and N'-desmethylsorafenib (25 μM) produced greater effects on ATP production than either treatment alone. Thus, it emerges that, by targeting the MEK/ERK pathway, multiple sorafenib metabolites may contribute to the actions of sorafenib in breast cancer. Because N'-desmethylsorafenib is not extensively metabolized and does not inhibit major hepatic CYPs, this metabolite may have a lower propensity to precipitate pharmacokinetic drug interactions than sorafenib.

Preclinical evaluation of sorafenib-eluting stent for suppression of human cholangiocarcinoma cells

Background

Cholangiocarcinoma is a malignant tumor arising from the epithelium of the bile ducts. In this study, we prepared sorafenib-loaded biliary stents for potential application as drug-delivery systems for localized treatment of extrahepatic cholangiocarcinoma.

Methods

A sorafenib-coated metal stent was prepared using an electrospray system with the aid of poly(ɛ-caprolactone) (PCL), and then its anticancer activity was investigated using human cholangiocellular carcinoma (HuCC)-T1 cells in vitro and a mouse tumor xenograft model in vivo. Anticancer activity of sorafenib against HuCC-T1 cells was evaluated by the proliferation test, matrix metalloproteinase (MMP) activity, cancer cell invasion, and angiogenesis assay in vitro and in vivo.

Results

The drug-release study showed that the increased drug content on the PCL film induced a faster drug-release rate. The growth of cancer cells on the sorafenib-loaded PCL film surfaces decreased in a dose-dependent manner. MMP-2 expression of HuCC-T1 cells gradually decreased according to sorafenib concentration. Furthermore, cancer cell invasion and tube formation of human umbilical vein endothelial cells significantly decreased at sorafenib concentrations higher than 10 mM. In the mouse tumor xenograft model with HuCC-T1 cells, sorafenib-eluting PCL films significantly inhibited the growth of tumor mass and induced apoptosis of tumor cells. Various molecular signals, such as B-cell lymphoma (Bcl)-2, Bcl-2-associated death promoter, Bcl-x, caspase-3, cleaved caspase-3, Fas, signal transducer and activator of transcription 5, extracellular signal-regulated kinases, MMP-9 and pan-janus kinase/stress-activated protein kinase 1, indicated that apoptosis, inhibition of growth and invasion was cleared on sorafenib-eluting PCL films.

Conclusion

These sorafenib-loaded PCL films are effective in inhibiting angiogenesis, proliferation and invasion of cancer cells. We suggest that sorafenib-loaded PCL film is a promising candidate for the local treatment of cholangiocarcinoma.

Sequence dependence of MEK inhibitor AZD6244 combined with gemcitabine for the treatment of biliary cancer

PURPOSE

MEK inhibition has clinical activity against biliary cancers and might therefore be successfully combined with gemcitabine, one of the most active chemotherapy agents for these cancers. As gemcitabine is active in S-phase, and the extracellular signal-regulated kinase (ERK) pathway has a major role driving cell-cycle progression, concurrent use of a MEK inhibitor could potentially antagonize the effect of gemcitabine. We therefore tested the sequence dependence of the combination of gemcitabine and the MEK inhibitor AZD6244 using a series of biliary cancer models.

EXPERIMENTAL DESIGN

Primary xenografts were established from patients with gallbladder and distal bile duct cancer and grown in severe combined immunodeficient (SCID) mice at the subcutaneous site. Plasma and tumor drug levels and the time course for recovery of ERK signaling and S-phase were measured in tumor-bearing mice treated for 48 hours with AZD6244 and then monitored for 48 hours off treatment. On the basis of these results, two different treatment schedules combining AZD6244 with gemcitabine were tested in four different biliary cancer models.

RESULTS

DNA synthesis was suppressed during treatment with AZD6244, and reentry into S-phase was delayed by approximately 48 hours after treatment. Strong schedule dependence was seen in all four biliary cancer models tested, suggesting that combined treatment with AZD6244 plus gemcitabine would be more active in patients with biliary cancer when gemcitabine is given following a 48-hour interruption in AZD6244 dosing, rather than concurrently.

CONCLUSIONS

The combination of AZD6244 plus gemcitabine is highly schedule dependent, and predicted to be more effective in the clinic using sequential rather than simultaneous dosing protocols.

Safety and pharmacokinetics of ganitumab (AMG 479) combined with sorafenib, panitumumab, erlotinib, or gemcitabine in patients with advanced solid tumors

PURPOSE

This phase 1b dose-escalation study assessed safety, tolerability, and pharmacokinetics of ganitumab, a fully human monoclonal antibody against the insulin-like growth factor 1 (IGF1) receptor, combined with targeted agents or cytotoxic chemotherapy in patients with advanced solid tumors.

EXPERIMENTAL DESIGN

Patients with treatment-refractory advanced solid tumors were sequentially enrolled at 2 ganitumab dose levels (6 or 12 mg/kg i.v. every 2 weeks) combined with either sorafenib 400 mg twice daily, panitumumab 6 mg/kg every 2 weeks, erlotinib 150 mg once daily, or gemcitabine 1,000 mg/m(2) on days 1, 8, and 15 of each 4-week cycle. The primary end points were safety and pharmacokinetics of ganitumab.

RESULTS

Ganitumab up to 12 mg/kg appeared well tolerated combined with sorafenib, panitumumab, erlotinib, or gemcitabine. Treatment-emergent adverse events were generally mild and included fatigue, nausea, vomiting, and chills. Three patients had dose-limiting toxicities: grade 3 hyperglycemia (ganitumab 6 mg/kg and panitumumab), grade 4 neutropenia (ganitumab 6 mg/kg and gemcitabine), and grade 4 thrombocytopenia (ganitumab 12 mg/kg and erlotinib). Ganitumab-binding and panitumumab-binding antibodies were detected in 5 and 2 patients, respectively; neutralizing antibodies were not detected. The pharmacokinetics of ganitumab and each cotherapy did not appear affected by coadministration. Circulating total IGF1 and IGF binding protein 3 increased from baseline following treatment. Four patients (9%) had partial responses.

CONCLUSIONS

Ganitumab up to 12 mg/kg was well tolerated, without adverse effects on pharmacokinetics in combination with either sorafenib, panitumumab, erlotinib, or gemcitabine. Ganitumab is currently under investigation in combination with some of these and other agents.

Potent in vitro and in vivo antitumor activity of sorafenib against human intrahepatic cholangiocarcinoma cells

BACKGROUND

Intrahepatic cholangiocarcinoma (ICC) is rising in clinical importance due to the increasing incidence worldwide, poor prognosis, and suboptimal response to therapies. New effective therapeutic approaches are needed for improvement of treatment outcome. A recent study showed that sorafenib, a multikinase inhibitor that acts predominantly through inhibition of Raf kinase and vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) receptors, exhibited potent antitumor activity in a preclinical model of cholangiocarcinoma cells.

METHOD

We tested the in vitro and in vivo antitumor activity of sorafenib against human ICC cell lines.

RESULTS

Treatment of ICC cells with sorafenib resulted in inhibition of proliferation and induction of apoptosis in the cell lines. In the cells treated with sorafenib, phosphorylation of mitogen-activated protein kinase kinase (MEK) and mitogen-activated protein kinase (MAPK) and also interleukin-6-induced phosphorylation of signal transducer and activator of transcription 3 (STAT3) were inhibited in a dose-dependent manner. Down-regulation of the anti-apoptotic protein myeloid cell leukemia-1 (Mcl-1) paralleled the reduced phosphorylation of STAT3. However, sorafenib induced no significant change in the cell cycle distribution and the expression levels of cyclin D1 and p27(Kip1) in the cells. For the in vivo antitumor activity, oral administration of sorafenib significantly inhibited the growth of subcutaneous tumors established in immunodeficient mice at doses of 10, 30, and 100 mg/kg. Moreover, administration of sorafenib (30 mg/kg) to animals with peritoneally disseminated ICC resulted in significantly prolonged survival compared with that of untreated animals (76 vs. 43 days in treated and vehicle-treated mice, respectively).

CONCLUSION

These results indicate that sorafenib is a potent agent that may provide a new therapeutic option for human ICC.

Sorafenib in unresectable intrahepatic cholangiocellular carcinoma: a case report

BACKGROUND

The oral multikinase inhibitor sorafenib is the new reference standard for the treatment of advanced hepatocellular carcinoma. Only few data are available on the use of sorafenib in cholangiocellular carcinoma (CCC).

METHODS

A 70-year-old male patient with histologically confirmed unresectable intrahepatic cholangiocellular carcinoma not amenable to any other systemic chemotherapy was treated with sorafenib 400 mg bid.

RESULTS

Sorafenib treatment led to a significant improvement of tumor symptoms, liver function parameters, and a decrease in tumor marker levels. The best radiologic tumor response according to RECIST and mRECIST was stable disease (SD) with a time to progression (TTP) of 5.7 months. Side effects of sorafenib (diarrhea, fatigue, and skin toxicity) were low-grade and manageable. Twenty-four months after sorafenib initiation the patient is still alive and presents in a well-preserved physical constitution, performance status 0. Gene analyses revealed that neither B-raf nor K-ras was mutated in our patient.

CONCLUSIONS

Sorafenib was effective and well-tolerated in a patient with advanced cholangiocellular carcinoma. Prospective trials are warranted to evaluate the benefit of sorafenib in unresectable CCC.

Targeting the IL-6 dependent phenotype can identify novel therapies for cholangiocarcinoma

Background

The need for new therapies for cholangiocarcinoma is highlighted by their poor prognosis and refractoriness to chemotherapy. Increased production of Interleukin-6 promotes cholangiocarcinoma growth and contributes to chemoresistance by activating cell survival mechanisms. We sought to identify biologically active compounds capable of ameliorating the phenotypic effects of IL-6 expression and to explore their potential therapeutic use for cholangiocarcinoma.

Methodology

A genomic signature associated with Interleukin-6 expression in Mz-ChA-1 human malignant cholangiocytes was derived. Computational bioinformatics analysis was performed to identify compounds that induced inverse gene changes to the signature. The effect of these compounds on cholangiocarcinoma growth was then experimentally verified in vitro and in vivo. Interactions with other therapeutic agents were evaluated using median effects analysis.

Principal Findings

A group of structurally related compounds, nitrendipine, nifedipine and felodipine was identified. All three compounds were cytotoxic to Mz-ChA-1 cells with an IC50 for felodipine of 26 µM, nitrendipine, 44 µM and nifedipine, 15 µM. Similar results were observed in KMCH-1, CC-LP-1 and TFK-1 cholangiocarcinoma cell lines. At a fractional effect of 0.5, all three agents were synergistic with either camptothecin or gemcitabine in Mz-ChA-1 cells in vitro. Co-administration of felodipine and gemcitabine decreased the growth of Mz-ChA-1 cell xenografts in nude athymic mice.

Conclusions

Computational bioinformatics analysis of phenotype-based genomic expression can be used to identify therapeutic agents. Using this drug discovery approach based on targeting a defined tumor associated phenotype, we identified compounds with the potential for therapeutic use in cholangiocarcinoma.

Targeting EGFR/HER2 pathways enhances the antiproliferative effect of gemcitabine in biliary tract and gallbladder carcinomas

Background

Advanced biliary tract carcinomas (BTCs) have poor prognosis and limited therapeutic options. Therefore, it is crucial to combine standard therapies with molecular targeting. In this study EGFR, HER2, and their molecular transducers were analysed in terms of mutations, amplifications and over-expression in a BTC case series. Furthermore, we tested the efficacy of drugs targeting these molecules, as single agents or in combination with gemcitabine, the standard therapeutic agent against BTC.

Methods

Immunohistochemistry, FISH and mutational analysis were performed on 49 BTC samples of intrahepatic (ICCs), extrahepatic (ECCs), and gallbladder (GBCs) origin. The effect on cell proliferation of different EGFR/HER2 pathway inhibitors as single agents or in combination with gemcitabine was investigated on BTC cell lines. Western blot analyses were performed to investigate molecular mechanisms of targeted drugs.

Results

EGFR is expressed in 100% of ICCs, 52.6% of ECCs, and in 38.5% of GBCs. P-MAPK and p-Akt are highly expressed in ICCs (>58% of samples), and to a lower extent in ECCs and GBCs (<46%), indicating EGFR pathway activation. HER2 is overexpressed in 10% of GBCs (with genomic amplification), and 26.3% of ECCs (half of which has genomic amplification). EGFR or its signal transducers are mutated in 26.5% of cases: 4 samples bear mutations of PI3K (8.2%), 3 cases (6.1%) in K-RAS, 4 (8.2%) in B-RAF, and 2 cases (4.1%) in PTEN, but no loss of PTEN expression is detected. EGI-1 cell line is highly sensitive to gemcitabine, TFK1 and TGBC1-TKB cell lines are responsive and HuH28 cell line is resistant. In EGI-1 cells, combination with gefitinib further increases the antiproliferative effect of gemcitabine. In TFK1 and TGBC1-TKB cells, the efficacy of gemcitabine is increased with addiction of sorafenib and everolimus. In TGBC1-TKB cells, lapatinib also has a synergic effect with gemcitabine. HuH28 becomes responsive if treated in combination with erlotinib. Moreover, HuH28 cells are sensitive to lapatinib as a single agent. Molecular mechanisms were confirmed by western blot analysis.

Conclusion

These data demonstrate that EGFR and HER2 pathways are suitable therapeutic targets for BTCs. The combination of gemcitabine with drugs targeting these pathways gives encouraging results and further clinical studies could be warranted.

Multimodal oncological therapy comprising stents, brachytherapy, and regional chemotherapy for cholangiocarcinoma

BACKGROUND/AIMS

To prospectively evaluate our palliative management of unresectable cholangiocarcinoma (CC) treated with tailored multimodal oncological therapy.

METHODS

Between January 2005 and January 2010, 50 consecutive patients with unresectable CC and jaundice were palliated with percutaneous drainage. Forty-three patients underwent metallic-stent implantation followed by brachytherapy. Patients were divided into two arms: the intra-arterial chemotherapy arm (IA arm, n=17) consisted of patients treated with locoregional treatment (IA admission of Cisplatin and 5-fluorouracil, or chemoembolization with Lipiodol) and/or systemic chemotherapy, while the systemic chemotherapy arm (IV arm, n=23) included all the other patients, who were treated only with systemic chemotherapy.

RESULTS

In total, 78 metal self-expandable stents were placed. Hilar involvement with mass-forming and periductal infiltrating types of CC (84%) was predominant. The average number of percutaneous interventional procedures was 11.61 per patient (range, 4-35). The median overall survival from diagnosis of disease for all patients was 13.5 months (range, 11.0-18.8 months). The median overall survival times were 25.2 months (range, 15.2-31.3 months) and 11.5 months (range, 8.5-12.6 months) in the IA and IV arms, respectively (p<0.05). The 1-, 2-, and 3-year survival rates in the IA and IV arms were 88.2%, 52.9%, and 10.1% and 43.5%, 25.4, and 0%, respectively. There were no major complications (WHO III/IV) due to interventional procedures.

CONCLUSIONS

We could reach acceptable prognosis in patients with unresectable CC using complex tailored oncological therapy. However, the main limitations of prolonging survival are performance status, patient compliance and the maintaining of biliary tract patency.

Targeted therapy in biliary tract cancer: 2009 update

Biliary tract cancers (BTCs) include cholangiocarcinoma (intrahepatic, perihilar and extrahepatic), carcinoma of the gall bladder and ampullary carcinoma. In patients with advanced disease the prognosis is poor. There is not a consensus regarding treatment strategy. Chemotherapy has only limited efficacy. This review summarizes the new approaches for BTC patients and the rationale for targeted therapies. The prognostic factors and the molecular features of BTC are analyzed. The clinical trials evaluating the targeted agents are accurately described, especially those assessing the role of anti-EGFR and antiangiogenic drugs. The ongoing trials are also analyzed. In fact, only the results of these trials will establish which is the most effective agent or combination for this setting.

The potential role of sunitinib in gastrointestinal cancers other than GIST

Gastrointestinal tumors are the most frequent and lethal malignancies worldwide. The deeper knowledge in molecular biology mechanisms involved in carcinogenesis has allowed the design of new targeted drugs mainly directed against the epidermal growth factor receptor (EGFR), the vascular endothelial growth factor (VEGF) and its receptors (VEGFRs). Sunitinib is an oral multitargeted inhibitor of the VEGF, platelet-derived growth factor (PDGF), and c-KIT, among others, tyrosine kinase receptors. Therefore, sunitinib acts in a dual mode as antiangiogenic agent and as antitumoral drug. The aim of this review is to gather the preclinical rationale behind the clinical use of sunitinib in gastrointestinal malignancies other than gastrointestinal stromal tumors (GIST) and to summarize the clinical data from phase I to III trials currently available.

Synergistic activity of letrozole and sorafenib on breast cancer cells

Estrogens induce breast tumor cell proliferation by directly regulating gene expression via the estrogen receptor (ER) transcriptional activity and by affecting growth factor signaling pathways such as mitogen-activated protein kinase (MAPK) and AKT/mammalian target of rapamycin Complex1 (mTORC1) cascades. In this study we demonstrated the preclinical therapeutic efficacy of combining the aromatase inhibitor letrozole with the multi-kinase inhibitor sorafenib in aromatase-expressing breast cancer cell lines. Treatment with letrozole reduced testosterone-driven cell proliferation, by inhibiting the synthesis of estrogens. Sorafenib inhibited cell proliferation in a concentration-dependent manner; this effect was not dependent on sorafenib-mediated inhibition of Raf1, but involved the down-regulation of mTORC1 and its targets p70S6K and 4E-binding protein 1 (4E-BP1). At concentrations of 5-10 μM the growth-inhibitory effect of sorafenib was associated with the induction of apoptosis, as indicated by release of cytochrome c and Apoptosis-Inducing Factor into the cytosol, activation of caspase-9 and caspase-7, and PARP-1 cleavage. Combination of letrozole and sorafenib produced a synergistic inhibition of cell proliferation associated with an enhanced accumulation of cells in the G(0)/G(1) phase of the cell cycle and with a down-regulation of the cell cycle regulatory proteins c-myc, cyclin D1, and phospho-Rb. In addition, longer experiments (12 weeks) demonstrated that sorafenib may be effective in preventing the acquisition of resistance towards letrozole. Together, these results indicate that combination of letrozole and sorafenib might constitute a promising approach to the treatment of hormone-dependent breast cancer.