mTOR Inhibition Is Most Beneficial After Liver Transplantation for Hepatocellular Carcinoma in Patients With Active Tumors.

OBJECTIVE: The aim of this study was to evaluate the survival benefit of sirolimus in patients undergoing liver transplantation (LT) for hepatocellular carcinoma (HCC) (exploratory analysis of the SiLVER-trial). SUMMARY AND BACKGROUND DATA: Patients receiving LT) for HCC are at a high risk for tumor recurrence. Calcineurin inhibitors have shown evidence to promote cancer growth, whereas mammalian target of rapamycin (mTOR) inhibitors like sirolimus have anticancer effects. In the SiLVER-trial (Clinicaltrials.gov: NCT00355862), the effect of sirolimus on the recurrence of HCC after LT was investigated in a prospective randomized trial. Although the primary endpoint of improved disease-free survival (DFS) with sirolimus was not met, outcomes were improved for patients in the sirolimus-treatment arm in the first 3 to 5 years. To learn more about the key variables, a multivariate analysis was performed on the SiLVER-trial data. PATIENTS AND METHODS: Data from 508 patients of the intention-to-treat analysis were included in exploratory univariate and multivariate models for overall survival (OS), DFS and a competing risk analysis for HCC recurrence. RESULTS: Sirolimus use for ≥3 months after LT for HCC independently reduced the hazard for death in the multivariate analysis [hazard ratio (HR): 0.7 (95% confidence interval, CI: 0.52-0.96, P = 0.02). Most strikingly, patients with an alpha-fetoprotein (AFP) ≥10 ng/mL and having used sirolimus for ≥3 months, benefited most with regard to OS, DFS, and HCC-recurrence (HR: 0.49-0.59, P = 0.0079-0.0245). CONCLUSIONS: mTOR-inhibitor treatment with sirolimus for ≥3 months improves outcomes in LT for HCC, especially in patients with AFP-evidence of higher tumor activity, advocating particularly for mTOR inhibitor use in this subgroup of patients. CLINICAL TRIAL REGISTRATION: EudraCT: 2005-005362-36 CLINICALTRIALS.GOV:: NCT00355862.

Resminostat plus sorafenib as second-line therapy of advanced hepatocellular carcinoma - The SHELTER study.

BACKGROUND & AIMS: No established therapies for patients with hepatocellular carcinoma (HCC) and progression on first-line sorafenib treatment currently exist. This phase I/II trial investigated safety, pharmacokinetics and potential biomarkers of the histone deacetylase inhibitor resminostat and a combination therapy with resminostat and sorafenib. METHODS: Patients with HCC and radiologically confirmed progression on sorafenib were treated in an exploratory, multi-center, open-label, uncontrolled, non-randomized, parallel group phase I/II study. In the combination group (n=38) four dose levels ranged from daily 200 to 600mg resminostat plus 400 to 800mg sorafenib. The monotherapy group (n=19) received 600mg resminostat. RESULTS: 57 patients received treatment. Most common adverse events were gastrointestinal disorders, thrombocytopenia and fatigue. Median maximal histone deacetylase inhibition and highest increase in H4-acetylation matched Tmax of resminostat. Sorafenib or the Child-Pugh score did not affect typical pharmacokinetics characteristics of resminostat. Efficacy assessment as progression-free survival-rate after 6 treatment cycles (12weeks, primary endpoint) was 12.5% for resminostat and 62.5% for resminostat plus sorafenib. Median time to progression and overall survival were 1.8 and 4.1months for resminostat and 6.5 and 8.0months for the combination, respectively. Zinc finger protein 64 (ZFP64) baseline expression in blood cells was found to correlate with overall survival. CONCLUSIONS: The combination of sorafenib and resminostat in HCC patients was safe and showed early signs of efficacy. Sorafenib did not alter the pharmacokinetic profile of resminostat or its histone deacetylase inhibitory activity in vivo. A prognostic and potentially predictive role of ZFP64 for treatment with resminostat should be further investigated in HCC and possibly other cancer indications. LAY SUMMARY: No established therapy for patients with advanced hepatocellular carcinoma and progression under first-line systemic treatment with sorafenib currently exists. Epigenetic modulation by inhibition of histone deacetylases might be able to overcome therapy resistance. This exploratory phase I/II clinical study in patients with radiologically confirmed progression under first-line treatment with sorafenib investigated the histone deacetylases inhibitor resminostat as single agent or in combination with continued application of sorafenib. CLINICAL TRIAL REGISTRATION: The clinical trial has been registered at www.clinicaltrials.gov as NCT00943449.

Pancreatic Atrophy in Hepatocellular Carcinoma Patients Receiving Long-Term Treatment with Sorafenib.

OBJECTIVE: To date, sorafenib is the only approved systemic therapy for advanced hepatocellular carcinoma (HCC). Pancreatic atrophy has recently been reported in 2 patients as a novel side effect after long-term sorafenib treatment. METHODS: We retrospectively analyzed clinical and radiological data of patients with advanced HCC with long-term treatment of sorafenib (median 279 days, range 153-826 days). Pancreata were semi-manually segmented section by section to calculate the pancreas volumes before and under sorafenib treatment. RESULTS: Sorafenib reduced pancreatic volume in 18/19 (95%) HCC patients with a mean pancreatic volume loss of 25% (p = 0.002). Pancreatic volume loss depended on the dose (r = 0.36) and exposure time of sorafenib (r = 0.35) and was detectable as early as after 3 months of sorafenib treatment and already after a cumulative sorafenib dose of <100 g. Median overall survival was 13.2 months (range 7.8-31.3 months) but did not correlate with sorafenib-induced pancreatic volume reduction (hazard ratio 1.002, 95% confidence interval 0.981-1.060, p = 0.24). CONCLUSION: We could confirm pancreatic atrophy as a novel adverse event of sorafenib therapy in HCC patients, correlating with sorafenib dose and exposure time.

Analysis of hepatitis C virus resistance to silibinin in vitro and in vivo points to a novel mechanism involving nonstructural protein 4B.

UNLABELLED: Intravenous silibinin (SIL) is an approved therapeutic that has recently been applied to patients with chronic hepatitis C, successfully clearing hepatitis C virus (HCV) infection in some patients even in monotherapy. Previous studies suggested multiple antiviral mechanisms of SIL; however, the dominant mode of action has not been determined. We first analyzed the impact of SIL on replication of subgenomic replicons from different HCV genotypes in vitro and found a strong inhibition of RNA replication for genotype 1a and genotype 1b. In contrast, RNA replication and infection of genotype 2a were minimally affected by SIL. To identify the viral target of SIL we analyzed resistance to SIL in vitro and in vivo. Selection for drug resistance in cell culture identified a mutation in HCV nonstructural protein (NS) 4B conferring partial resistance to SIL. This was corroborated by sequence analyses of HCV from a liver transplant recipient experiencing viral breakthrough under SIL monotherapy. Again, we identified distinct mutations affecting highly conserved amino acid residues within NS4B, which mediated phenotypic SIL resistance also in vitro. Analyses of chimeric viral genomes suggest that SIL might target an interaction between NS4B and NS3/4A. Ultrastructural studies revealed changes in the morphology of viral membrane alterations upon SIL treatment of a susceptible genotype 1b isolate, but not of a resistant NS4B mutant or genotype 2a, indicating that SIL might interfere with the formation of HCV replication sites. CONCLUSION: Mutations conferring partial resistance to SIL treatment in vivo and in cell culture argue for a mechanism involving NS4B. This novel mode of action renders SIL an attractive candidate for combination therapies with other directly acting antiviral drugs, particularly in difficult-to-treat patient cohorts.

CYP3A activity in severe liver cirrhosis correlates with Child-Pugh and model for end-stage liver disease (MELD) scores.

AIMS: Impaired liver function often necessitates drug dose adjustment to avoid excessive drug accumulation and adverse events, but a marker for the extent of the required adjustment is lacking. The aim of this study was to investigate whether Child-Pugh (CP) and model for end-stage liver disease (MELD) scores correlate with drug clearance. METHODS: Midazolam was used as a CYP3A probe and its pharmacokinetics were analyzed in 24 patients with mild to severe liver cirrhosis (n = 4, 10 and 10 with CP class A, B and C, respectively) and six patients without liver disease. RESULTS: Both scores correlated well with unbound midazolam clearance (CLu ), unbound midazolam fraction and half-life (all P < 0.01), whereas the unbound steady-state volume of distribution was not significantly changed. In patients with severe liver cirrhosis unbound midazolam clearance was only 14% of controls (CP C: CLu = 843 ± 346 l h(-1), MELD ≥ 15: CLu = 805 ± 474 l h(-1), controls: CLu = 5815 ± 2649 l h(-1), P < 0.01). CONCLUSION: The correlation with unbound midazolam clearance suggests that either score predicts the metabolic capacity of CYP3A, the most relevant drug metabolizing enzyme subfamily in humans.

Diarrhea is a positive outcome predictor for sorafenib treatment of advanced hepatocellular carcinoma.

OBJECTIVE: This study was performed to identify clinical predictors for better survival in patients with advanced hepatocellular carcinoma (HCC) under sorafenib treatment. METHODS: Between December 2007 and January 2010, 46 patients with advanced HCC were treated with sorafenib until significant tumor progression or intolerable toxicity. We prospectively collected clinical baseline data as well as data on the incidence and severity of toxic side effects of sorafenib to be correlated with progression-free survival and overall survival (OS), respectively. RESULTS: Only 26.1% (n = 12) of patients tolerated sorafenib without requiring dose reduction. The most frequent grade 3 toxicities were diarrhea (32.6%), hand-foot skin reaction (13.0%), fatigue (4.3%), and nausea/vomiting (2.2%). Eastern Cooperative Oncology Group performance status (p = 0.034) and portal vein infiltration (p = 0.021) significantly correlated with OS. Furthermore, we found a significant correlation between OS and appearance of grade 2 or 3 diarrhea with a median actuarial survival of 11.8 months (95% CI 6.9-16.6) compared to 4.2 months in patients with grade 0 or 1 diarrhea (95% CI 0.0-9.1; p = 0.009). In contrast, appearance of hand-foot skin reaction did neither correlate with progression-free survival nor with OS. CONCLUSION: Appearance of grade 2 or 3 diarrhea indicates a better OS of HCC patients undergoing sorafenib treatment.

Cytosolic and nuclear caspase-8 have opposite impact on survival after liver resection for hepatocellular carcinoma.

BACKGROUND: An imbalance between proliferation and apoptosis is one of the main features of carcinogenesis. TRAIL (TNF-related apoptosis-inducing ligand) induces apoptosis upon binding to the TRAIL death receptors, TRAIL receptor 1 (TRAIL-R1) and TRAIL-R2, whereas binding to TRAIL-R3 and TRAIL-R4 might promote cell survival and proliferation. The anti-tumor activity of TRAIL-R1 and TRAIL-R2 agonists is currently investigated in clinical trials. To gain further insight into the regulation of apoptosis in hepatocellular carcinoma (HCC), we investigated the TRAIL pathway and the regulators of apoptosis caspase-8, Bcl-xL and Mcl-1 in patients with HCC regarding patient survival. METHODS: We analyzed 157 hepatocellular carcinoma patients who underwent partial liver resection or orthotopic liver transplantation and healthy control liver tissue using immunohistochemistry on tissue microarrays for the expression of TRAIL-R1 to TRAIL-R4, caspase-8, Bcl-xL and Mcl-1. Immunohistochemical data were evaluated for potential associations with clinico-pathological parameters and survival. RESULTS: Whereas TRAIL-R1 was downregulated in HCC in comparison to normal liver tissue, TRAIL-R2 and -R4 were upregulated in HCC, especially in G2 and G3 tumors. TRAIL-R1 downregulation and upregulation of TRAIL-R2 and TRAIL-R4 correlated with tumor dedifferentiation (G2/G3). TRAIL-R3, Bcl-xL and Mcl-1 showed no differential expression in tumor tissue compared to normal tissue. The expression levels of TRAIL receptors did not correlate with patient survival after partial hepatectomy. Interestingly, in tumor tissue, but not in normal hepatocytes, caspase-8 showed a strong nuclear staining. Low cytosolic and high nuclear staining intensity of caspase-8 significantly correlated with impaired survival after partial hepatectomy, which, for cytosolic caspase-8, was independent from tumor grade. CONCLUSIONS: Assessment of TRAIL-receptor expression patterns may have therapeutic implications for the use of TRAIL receptor agonists in HCC therapy. Tumor-specific nuclear localisation of caspase-8 in HCC suggests an apoptosis-independent function of caspase-8 and correlates with patient survival.

Liver allocation: urgency of need or prospect of success? Ethical considerations.

In German legislation and in Eurotransplant's practice of liver allocation, urgency of need is considered as the primary distribution criterion. However, at a certain stage, the "sickest-first" principle is regarded as counterproductive as the performance status of these patients receiving an organ is on average critical and mortality and morbidity after liver transplantation increase. Within the medical transplant community, the criterion of prospect for success is highly accepted. As clinicians having a certain scope in decision-making as "gatekeepers" in regard to which patient gets on the waiting list and at which stage a patient is defined as "not transplantable" and as transplantation centers aspire good success rates, the goal of high prospect for success might become more weighty than intended by legislation and professional guidelines. From an ethical point of view, it is submitted a so-called mediatory approach in between the two extremes "sickest-first" and "fittest-first." Beyond that, it is argued for further development of a prognostic score for post-operative outcome after liver transplantation - as long as questions of social justice are borne in mind - to support "objective" decision-making.

Effects of mycophenolate mofetil introduction in liver transplant patients: results from an observational, non-interventional, multicenter study (LOBSTER).

The benefits of calcineurin inhibitor (CNI)-sparing regimens on renal function following liver transplantation (LT) have been demonstrated in clinical studies. This observational study assessed the real-life effects of mycophenolate mofetil (MMF) introduction in LT patients. Four hundred and ninety-seven patients in whom MMF was introduced according to local standards or clinical considerations were entered. Patients were grouped by time between transplantation and start of MMF (start of study): Group A (n = 263): ≤6 d; Group B (n = 64): >6 d to ≤1 month; Group C (n = 74): >1 month to ≤1 yr; and Group D (n = 96): >1 yr. CNI sparing occurred in all groups, particularly in Groups C and D. Mean MMF doses at 12 months were 1202.7, 1363.5, 1504.7, and 1578.1 mg/d, respectively, in Groups A-D. At introduction of MMF, median glomerular filtration rate was 73.3, 81.7, 62.7, and 53.7 mL/min/1.73 m(2) in Groups A-D. At 12 months, this decreased to 66 mL/min/1.73 m(2) in Groups A and B, remained stable in Group C, and increased in Group D (64.8 mL/min/1.73 m(2) ). Serious adverse drug reactions were lowest in Group D. In conclusion, MMF with a subsequent decrease in CNI was well tolerated and improved renal function even years after transplantation. A more forceful MMF dosing strategy with greater CNI sparing may further improve renal function.

Sorafenib treatment is save and may affect survival of recurrent hepatocellular carcinoma after liver transplantation.

INTRODUCTION: Recurrent hepatocellular carcinoma (HCC) after liver transplantation (LT) is a rare but challenging condition. In most cases, the recurrent tumor is presented with extrahepatic spread. Therefore, systemic treatment with sorafenib has to be assessed. Because of a plethora of possible drug interactions, e.g., with immunosuppressant or anti-infective therapy, safety and feasibility of sorafenib treatment requires special attention. MATERIALS AND METHODS: We retrospectively analyzed 18 patients who suffered from recurrent advanced HCC after LT between January 2002 and December 2010 at the University Hospital Heidelberg regarding safety of sorafenib treatment and survival. RESULTS: Results showed that 8 patients were eligible for treatment with sorafenib showing a median time to progression (TTP) of 4.5 months and an overall survival of 9 months. Most common side effects were grades I and II diarrhea and hand-foot syndrome (HFS) which could be managed by sorafenib dose reduction. No grade III or IV adverse events (AEs) were noticed. No patient had to discontinue treatment due to AEs. The ten patients not amenable for sorafenib treatment, due to initial poor performance status or its deterioration after first line treatment, were treated with surgical resection (n = 3), locoregional therapies (n = 1), or palliative radiation therapy (n = 1). They showed a median overall survival of 2.3 months. CONCLUSION: Sorafenib may represent a therapeutic option for recurrent HCC after LT with manageable side effects. The clinical benefit of sorafenib in this setting is promising but needs to be confirmed in a prospective randomized trial.

The role of HBIg as hepatitis B reinfection prophylaxis following liver transplantation.

BACKGROUND AND INTRODUCTION: Without adequate prophylaxis, liver transplantation (LTx) is frequently followed by hepatitis B virus (HBV) reinfection, which results in rapidly progressing liver disease and significantly decreased overall survival. In the last two decades, significant progress has been made in the prophylaxis and treatment of HBV. DISCUSSION: We present an overview of different protocols and regimens used for prophylaxis of HBV reinfection after LTx and describe the protocol implemented at our center. Following LTx, HBV reinfection can be effectively prevented by administration of anti-hepatitis B immunoglobulin (HBIg) alone or more recently in combination with antiviral nucleoside/nucleotide analogs (NUCs). Several studies reported good results with the use of HBIg alone, but combination treatment with HBIg and NUCs has proven to be a superior prophylactic regimen for HBV recurrence. At present, combination therapy (HBIg and a nucleoside or nucleotide analog) is the gold standard used in many transplantation centers. This preventive regimen reduces the risk of a recurrence of HBV infection and thereby the need for re-transplantation. Future and ongoing studies will show how long HBIg must be given after transplantation, especially when used in combination with potent antivirals, such as entecavir or tenofovir.

Risk factors of survival after liver transplantation for HCC: a multivariate single-center analysis.

BACKGROUND: The selection criteria for liver transplantation (LT) in patients with hepatocellular cancer (HCC) are well defined. Increasing evidence suggests that the effectiveness of pre-transplant bridging influences the individual course after LT significantly. Thus, the aim of this study was to determine its impact on tumor progression during waiting time and identify patient subgroups with favorable oncological long-term outcome. METHODS: Prospectively collected data of 78 consecutive patients undergoing LT for HCC between 2001 and 2007 were analyzed retrospectively. Survival rates were assessed using the Kaplan-Meier estimate. Clinicopathologic prognostic factors were identified by Cox regression analysis. RESULTS: After 48.9 months of median follow-up, the five-yr overall survival rate is 57% with a five-yr recurrence-free survival rate of 74%. Progressive disease (PD) during bridging was developed in 32% of patients, and a trend toward impaired overall survival in patients with PD before LT was detected in multivariate analysis (p = 0.073). HCC ≥3 cm was associated with a three times increased risk of recurrent disease. Neither fulfillment of MILAN criteria nor bridging with transarterial chemoembolization had an impact on the outcome. CONCLUSION: PD during waiting time influences the oncological course after LT. However, even with an increasing organ shortage, further studies are warranted to define clear selection criteria based on the biological tumor behavior and allow a more personalized treatment.

Bortezomib sensitizes primary human esthesioneuroblastoma cells to TRAIL-induced apoptosis.

TNF-related apoptosis-inducing ligand (TRAIL), a promising novel anti-cancer cytokine of the TNF superfamily, and Bortezomib, the first-in-class clinically used proteasome inhibitor, alone or in combination have been shown to efficiently kill numerous tumor cell lines. However, data concerning primary human tumor cells are very rare. Using primary esthesioneuroblastoma cells we analyzed the anti-tumor potential and the mechanism employed by Bortezomib in combination with TRAIL for the treatment of this rare but aggressive tumor. Expression of components of the TRAIL pathway was analyzed in tumor specimens and isolated primary tumor cells at the protein level. Cells were treated with TRAIL, Bortezomib, and a combination thereof, and apoptosis induction was quantified. Clonogenicity assays were performed to elucidate the long-term effect of this treatment. Despite expressing all components of the TRAIL pathway, freshly isolated primary esthesioneuroblastoma cells were completely resistant to TRAIL-induced apoptosis. They could, however, be very efficiently sensitized by subtoxic doses of Bortezomib. The influence of Bortezomib on the TRAIL pathway was analyzed and showed upregulation of TRAIL death receptor expression, enhancement of the TRAIL death-inducing signaling complex (DISC), and downregulation of anti-apoptotic proteins of the TRAIL pathway. Of clinical relevance, TRAIL-resistant primary tumor cells could be repeatedly sensitized by Bortezomib, providing the basis for repeated clinical application schedules. This is the first report on the highly synergistic induction of apoptosis in primary esthesioneuroblastoma cells by Bortezomib and TRAIL. This combination, therefore, represents a promising novel therapeutic option for esthesioneuroblastoma.

Beyond Milan criteria--chances and risks of expanding transplantation criteria for HCC patients with liver cirrhosis.

Orthotopic liver transplantation (OLT) is, apart from resection, one important curative treatment for hepatocellular carcinoma (HCC) in liver cirrhosis, and especially attractive because it eliminates both the tumor and the underlying liver disease. The application of restrictive inclusion criteria for OLT in HCC patients resulted in favorable long-term recurrence-free survival. These criteria, however, exclude a subgroup of patients which, despite advanced tumor size, demonstrate an acceptable outcome. As a consequence, expansion of the strict Milan criteria has been discussed. However, this will also deteriorate the average outcome of OLT in HCC patients. Considering that we run short of donor organs, more sophisticated prediction models for survival after OLT for HCC patients are needed to identify patients who benefit best from OLT. Neoadjuvant treatment that is frequently applied as a bridging technique for patients on the waiting list for OLT could provide useful information on tumor behavior to better predict the risk of post-OLT tumor recurrence. This might also allow expansion of the Milan criteria to patients with good response to downstaging methods without negatively affecting post-OLT survival. Furthermore, alternative scoring systems have been suggested to identify HCC patients that might still benefit from resection instead of OLT, and molecular tools are being explored to provide predictive information on HCC biology. This review discusses the advantages and risks of extended inclusion criteria for OLT and the currently available data on alternative prediction models and bridging methods in HCC patients.

TRAIL and other TRAIL receptor agonists as novel cancer therapeutics.

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), also known as Apo2L, is a member of the TNF superfamily (TNFSF) of cytokines. TRAIL gained much attention during the past decade due to the demonstration of its therapeutic potential as a tumor-specific apoptosis inducer. TRAIL was identified as a protein with high homology to other members of the TNF cytokine family, especially to the ligand of Fas/Apo-1 (CD95), CD95L (FasL/APO-1L). TRAIL has been shown to induce apoptosis selectively in many tumor cell lines without affecting normal cells and tissues, making TRAIL itself as well as agonists of the two human receptors of TRAIL which can submit an apoptotic signal, TRAIL-R1 (DR4) and TRAIL-R2 (DR5), promising novel biotherapeutics for cancer therapy. An increasing number of publications now shows that TRAIL resistance in primary human tumor cells will have to be overcome and that sensitization to TRAIL-induced apoptosis will be required in many cases. Therefore, it will also be instrumental to develop suitable diagnostic tests to identify patients who will benefit from TRAIL-based novel anticancer therapeutics and those who will not. Interestingly, the first clinical results even in monotherapy with TRAIL as well as various agonistic TRAIL receptor-specific antibodies have shown encouraging results. This chapter provides a compact overview on the biochemistry of the TRAIL/TRAIL-R system, the physiological role of TRAIL and its receptors and the results of clinical trials with TRAIL and various TRAIL-R agonistic antibodies.

Bortezomib sensitizes primary human astrocytoma cells of WHO grades I to IV for tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis.

PURPOSE: Malignant gliomas are the most aggressive human brain tumors without any curative treatment. The antitumor effect of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in gliomas has thus far only been thoroughly established in tumor cell lines. In the present study, we investigated the therapeutic potential of TRAIL in primary human glioma cells. EXPERIMENTAL DESIGN: We isolated primary tumor cells from 13 astrocytoma and oligoastrocytoma patients of all four WHO grades of malignancy and compared the levels of TRAIL-induced apoptosis induction, long-term tumor cell survival, caspase, and caspase target cleavage. RESULTS: We established a stable culture model for isolated primary human glioma cells. In contrast to cell lines, isolated primary tumor cells from all investigated glioma patients were highly TRAIL resistant. Regardless of the tumor heterogeneity, cotreatment with the proteasome inhibitor bortezomib efficiently sensitized all primary glioma samples for TRAIL-induced apoptosis and tremendously reduced their clonogenic survival. Due to the pleiotropic effect of bortezomib-enhanced TRAIL DISC formation upon TRAIL triggering, down-regulation of cFLIP(L) and activation of the intrinsic apoptosis pathway seem to cooperatively contribute to the antitumor effect of bortezomib/TRAIL cotreatment. CONCLUSION: TRAIL sensitivity of tumor cell lines is not a reliable predictor for the behavior of primary tumor cells. The widespread TRAIL resistance in primary glioma cells described here questions the therapeutic clinical benefit of TRAIL as a monotherapeutic agent. Overcoming TRAIL resistance by bortezomib cotreatment might, however, provide a powerful therapeutic option for glioma patients.

The promise of TRAIL--potential and risks of a novel anticancer therapy.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising new anticancer biotherapeutic. As shown by many preclinical studies, TRAIL efficiently induces apoptosis in numerous tumor cell lines but not in the majority of normal cells. However, an increasing number of publications report on a predominance of TRAIL resistance in primary human tumor cells, which require sensitization for TRAIL-induced apoptosis. Sensitization of cancer cells by treatment with chemotherapeutic drugs and irradiation has been shown to restore TRAIL sensitivity in many TRAIL-resistant tumor cells. Accordingly TRAIL treatment has been successfully used in different in vivo models for the treatment of tumors also in combination with chemotherapeutics without significant toxicity. However, some reports demonstrated toxicity of TRAIL alone or in combination with chemotherapeutic drugs in normal cells. This review summarizes data concerning the apoptosis-inducing pathways and efficacy of TRAIL, alone or in combination with chemotherapeutic drugs, in primary cancer cells compared to the unwanted effects of TRAIL treatment on normal tissue. We discuss the different in vitro tumor cell models and the potential of different recombinant forms of TRAIL or agonistic antibodies to TRAIL death receptors. Most preclinical studies show a high efficiency of a combinatorial TRAIL-based therapy in animal models and in primary human ex vivo tumor cells with a low toxicity in normal cells. Accordingly clinical phase I/II studies have begun and will be developed further with caution.

Cytogenetic and molecular biological characterization of an adult medulloblastoma.

Medulloblastoma is a malignant invasive embryonal tumor, occurring in children mainly. It is rare in adults (<1% of adult brain tumors), and so comprehensive cytogenetic and molecular biological data on adult medulloblastomas are very limited. Conventional therapies provide disappointing long-term disease control, and new therapeutic options are being tested. We performed comprehensive cytogenetic analyses of an adult medulloblastoma, WHO grade IV, using trypsin-Giemsa staining (GTG-banding), multicolor fluorescence in situ hybridization (M-FISH), and locus-specific FISH, complemented by molecular karyotyping using high-density single nucleotide polymorphism (SNP) arrays. GTG-banding of 25 metaphases revealed 31 structural chromosomal aberrations, predominantly located on chromosomes 4q, 9q, 10q, 11p, and 20q, which were confirmed by M-FISH. Two novel, so far not described translocations were found: t(4;11)(q25;p15) and t(9;20)(p23;p12). GTG-banding, locus-specific FISH, and M-FISH detected numerical changes of chromosomes 8, 14, 18, 19, 20, 21, and 22. Molecular karyotyping by SNP array confirmed chromosomal changes -2p, -10q, -16q, and -Xq and revealed de novo partial uniparental disomy 1q and 9q. Applying an upcoming therapeutic approach, we found that primary medulloblastoma cells were resistant to TRAIL, a novel anticancer cytokine, but could be efficiently sensitized by cotreatment with the proteasome inhibitor bortezomib. Bortezomib-TRAIL cotreatment may serve as a powerful therapeutic option for medulloblastoma patients.

Preclinical differentiation between apparently safe and potentially hepatotoxic applications of TRAIL either alone or in combination with chemotherapeutic drugs.

PURPOSE: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo2L) exhibits potent antitumor activity on systemic administration in nonhuman primates without deleterious side effects for normal tissue. However, there is a controversy about the potential toxicity of TRAIL on human hepatocytes. The use of different recombinant TRAIL forms only partially explains the contradicting reports on TRAIL sensitivity in primary human hepatocytes (PHH). EXPERIMENTAL DESIGN: To clarify this issue, we comprehensively tested four different recombinant forms of TRAIL for their apoptosis-inducing capacity on PHH obtained from a total of 55 human livers between day 1 and day 8 of in vitro culture. RESULTS: One day after single-cell isolation, all but one recombinant form of TRAIL [i.e., an untagged form of TRAIL (TRAIL.0)] induced apoptosis in PHH. Apoptosis induction by TRAIL in these cells could only be fully inhibited by concomitant blockade of TRAIL receptor 1 and TRAIL receptor 2. At day 4 of in vitro culture, when surrogate markers indicated optimal hepatocyte in vitro function, only high doses of cross-linked FLAG-TRAIL killed PHH whereas the other three recombinant TRAIL forms did not. Strikingly, cotreatment of day 4 PHH with cisplatin sensitized for TRAIL-induced apoptosis whereas 5-fluorouracil, etoposide, gemcitabine, irinotecan, or oxaliplatin, which are commonly used in the treatment of gastrointestinal cancers, did not. CONCLUSION: Our data show that whereas TRAIL alone or together with selected chemotherapeutic drugs seems to be safe, the combination of TRAIL with cisplatin is toxic to PHH.

Sorafenib in Patients with Hepatocellular Carcinoma-Results of the Observational INSIGHT Study.

Purpose: Sorafenib is the only currently approved systemic therapy for advanced hepatocellular carcinoma (HCC). We aimed to evaluate the safety and efficacy of sorafenib therapy in patients with HCC under real-life conditions regarding patient, tumor characteristics, and any adverse events at study entry and at follow-up visits every 2 to 4 months.Experimental Design: The current INSIGHT study is a noninterventional, prospective, multicenter, observational study performed in 124 sites across Austria and Germany between 2008 and 2014.Results: Median overall survival and time to progression (RECIST) were found to be dependent on baseline Barcelona Clinic Liver Cancer (BCLC) tumor stage (A: 29.2, B: 19.6, C: 13.6, D: 3.1 and A: 6.0, B: 5.5, C: 3.9, and D: 1.7 months, respectively), Child-Pugh liver function (A: 17.6, B: 8.1, C: 5.6 and A: 5.3, B: 3.3, C: 2.5 months, respectively), and performance status of the patient; however, age did not affect prognosis. Sorafenib-related adverse events at any grade occurred in 64.9% of patients, with diarrhea (35.4%), hand-foot-skin reaction (16.6%), nausea (10.3%), and fatigue (11.2%) occurring most frequently.Conclusions: Sorafenib treatment was shown to be effective in a real-life setting, in agreement with previously reported clinical trial data. The therapy was found to have an acceptable safety profile, with predominantly mild to moderate side effects. Clin Cancer Res; 23(19); 5720-8. ©2017 AACR.