Locoregional immuno(bio)therapy for liver metastases

Likelihood-Ratio-Test Methods for Drug Safety Signal Detection from Multiple Clinical Datasets

Pre- and postmarket drug safety evaluations usually include an integrated summary of results obtained using data from multiple studies related to a drug of interest. This paper proposes three approaches based on the likelihood ratio test (LRT), called the LRT methods, for drug safety signal detection from large observational databases with multiple studies, with focus on identifying signals of adverse events (AEs) from many AEs associated with a particular drug or inversely for signals of drugs associated with a particular AE. The methods discussed include simple pooled LRT method and its variations such as the weighted LRT that incorporates the total drug exposure information by study. The power and type-I error of the LRT methods are evaluated in a simulation study with varying heterogeneity across studies. For illustration purpose, these methods are applied to Proton Pump Inhibitors (PPIs) data with 6 studies for the effect of concomitant use of PPIs in treating patients with osteoporosis and to Lipiodol (a contrast agent) data with 13 studies for evaluating that drug's safety profiles.

Transarterial chemoembolization (TACE) using mitomycin and lipiodol with or without degradable starch microspheres for hepatocellular carcinoma: comparative study

Background

To evaluate survival data and local tumor control after transarterial chemoembolization in two groups with different embolization protocols for the treatment of HCC patients.

Methods

Ninty-nine patients (mean age: 63.6 years), 78 male (78.8%) with HCC were repeatedly treated with chemoembolization in 4-week-intervals. Eighty-eight patients had BCLC-Stage-B and in 11 patients, chemoembolization was performed for bridging (BCLC-Stage-A). In total, 667 chemoembolization treatments were performed (mean 6.7 treatments/patient). The administered chemotherapeutic agent included mitomycin. For embolization, lipiodol only (n = 51;51.5%; mean age 63.8 years; 38 male), or lipiodol plus degradable starch microspheres (DSM) (n = 48; 48.5%; mean age 63.4 years; 40 male) were used. The local tumor response was assessed by MRI using Response Evaluation Criteria in Solid Tumors 1.1 (RECIST 1.1). Patient survival times were evaluated using Kaplan-Meier curves and log-rank tests.

Results

The local tumor control in the lipiodol-group was: PR (partial response) in 11 (21.6%), SD (stable disease) in 32 (62.7%) and PD (progressive disease) in 8 cases (15.7%). In the lipiodol-DSM-group, PR was seen in 14 (29.2%), SD in 22 (45.8%), and PD in 12 (25.0%) individuals (p = 0.211). The median survival of patients after chemoembolization with lipiodol was 25 months and in the lipiodol-DSM-group 28 months (p = 0.845).

Conclusion

Our data suggest a slight benefit of the use of lipiodol and DSM in comparison of using lipiodol only for chemoembolization of HCC in terms of local tumor control and survival data, this trend did not reach the level of significance.

Selective Internal Yttrium-90 Radioembolization Therapy (90Y-SIRT) Versus Best Supportive Care in Patients With Unresectable Metastatic Melanoma to the Liver Refractory to Systemic Therapy: Safety and Efficacy Cohort Study

OBJECTIVES

To investigate survival, efficacy, and safety of selective internal yttrium-90 radioembolization therapy (Y-SIRT) in patients with unresectable metastatic melanoma (MM) to liver refractory to systemic therapy.

METHODS

An IRB-approved retrospective review of 58 patients diagnosed with unresectable MM to the liver, refractory to systemic therapy, between February 2003 and March 2012 was conducted. Of these, 28 received resin-based Y-SIRT (group A), and 30 patients received best supportive care (group B). Survival was calculated using the Kaplan-Meier method and Cox proportional hazard models.

RESULTS

Groups A and B were similar for the Child-Pugh class, ECOG scores, age, sex, and race. Median overall survival (OS) from diagnosis of primary melanoma in groups A and B were 119.9 and 26.1 months, respectively (P<0.001). Median OS from hepatic metastasis in groups A and B were 19.9 and 4.8 months, respectively (P<0.0001). In group A, median OS from hepatic metastasis in the Child-Pugh A, B, and C patients was 37.7, 4.2, and 3.6 months, respectively (P<0.001). In group B, median OS from hepatic metastasis in the Child-Pugh A, B, and C patients was 7.8, 4.2, and 1.9 months, respectively (P=0.04). Within group A, median OS from first Y-SIRT was 10.1 months; median OS of the Child-Pugh A, B, and C patients from first Y-SIRT was 10.3, 1.2, and 0.9 months, respectively (P=0.04). Median OS from first Y-SIRT was significantly greater in the absence of diffuse (>10) liver metastases (15.1 vs. 4.7 mo, P=0.02), and in the absence of extrahepatic metastases (21.3 vs. 8.6 mo, P<0.001). Common clinical toxicities following Y-SIRT included abdominal pain (17.9%), fatigue (14.3%), and self-limiting grade III bilirubin toxicity (10.7%).

CONCLUSION

For patients with unresectable MM to the liver refractory to systemic therapy, resin-based Y was associated with longer survival from liver metastases than best supportive care. Child-Pugh A patients with <10 metastatic lesions and absence of extrahepatic metastases demonstrated greatest survival following Y-SIRT.

Preparation and Characterization of Hyaluronic Acid-Polycaprolactone Copolymer Micelles for the Drug Delivery of Radioactive Iodine-131 Labeled Lipiodol

Micelles, with the structure of amphiphilic molecules including a hydrophilic head and a hydrophobic tail, are recently developed as nanocarriers for the delivery of drugs with poor solubility. In addition, micelles have shown many advantages, such as enhanced permeation and retention (EPR) effects, prolonged circulation times, and increased endocytosis through surface modification. In this study, we measured the critical micelle concentrations, diameters, stability, and cytotoxicity and the cell uptake of micelles against hepatic cells with two kinds of hydrophilic materials: PEG-PCL and HA-g-PCL. We used ¹³¹I as a radioactive tracer to evaluate the stability, drug delivery, and cell uptake activity of the micelles. The results showed that HA-g-PCL micelles exhibited higher drug encapsulation efficiency and stability in aqueous solutions. In addition, the ¹³¹I-lipiodol loaded HA-g-PCL micelles had better affinity and higher cytotoxicity compared to HepG2 cells.

Enhancement of Intratumoral Chemotherapy with Cisplatin with or without Microwave Ablation and Lipiodol. Future Concept for Local Treatment in Lung Cancer

Novel therapies for lung cancer are being explored nowadays with local therapies being the tip of the arrow. Intratumoral chemotherapy administration and local microwave ablation have been investigated in several studies. It has been previously proposed that lipiodol has the ability to modify the microenvironment matrix. In our current study we investigated this theory in BALBC mice. In total 160 BALBC mice were divided in eight groups: a) control, b) cisplatin, c) microwave, d) microwave and lipiodol, e) cisplatin and lipiodol, f) microwave and cisplatin, g) lipiodol and h) lipiodol, cisplatin and microwave. Lewis lung carcinoma cell lines (10⁶) were injected into the right back leg of each mouse. After the 8th day, when the tumor volume was about 100mm³ the therapy application was initiated, once per week for four weeks. Magnetic resonance imaging was performed for each tumor when a mouse died or when sacrificed if they were still alive by the end of the experiment (8-Canal multifunctional spool; NORAS MRI products, Gmbh, Germany). Imaging and survival revealed efficient tumor apoptosis for the groups b,c,d,e and f. However; severe toxicity was observed in group h and no follow up was available for this group after the second week of therapy administration. Lipiodol in its current form does assist in a more efficient way the distribution of cisplatin, as the microwave apoptotic effect. Future modification of lipiodol might provide a more efficient method of therapy enhancement. Combination of drug and microwave ablation is possible and has an efficient apoptotic effect.

Phase I trial of hepatic arterial infusion of nanoparticle albumin-bound paclitaxel: toxicity, pharmacokinetics, and activity

Because liver involvement in patients with metastatic cancer has limited options and poor outcomes, we conducted a phase I study to determine the safety, activity, and pharmacokinetic characteristics of hepatic arterial infusion of nanoparticle albumin-bound paclitaxel (HAI nab-paclitaxel). Cohorts of three patients having predominant hepatic metastases received HAI nab-paclitaxel at three dose levels (180, 220, and 260 mg/m(2), respectively) infused for more than 1 hour every 3 weeks (3 + 3 design). Some patients participated in comparative pharmacokinetic studies (i.v. vs. HAI), receiving their first course i.v., to determine peak concentrations and effect of first-pass hepatic extraction compared with subsequent courses administered by HAI. The highest dose level was expanded to determine the safety and activity of HAI nab-paclitaxel. Thirty-eight patients were treated. There were no dose-limiting toxicities at doses up to 260 mg/m(2). Common adverse events included alopecia, fatigue, myelosuppresion, nausea, and vomiting. Three patients had stable disease for 4 or more months and 2 patients (1 of 12 with breast cancer and 1 of 1 with cervical cancer) achieved a partial response lasting for 5 and 15 months, respectively. Peak concentrations were lower (∼50%) with greater hepatic extraction of drug (∼42%) following HAI than i.v. infusion based on area under the curve comparison of drug exposure. HAI nab-paclitaxel showed partial hepatic extraction. At doses 260 mg/m(2) or less given for 1 hour every 3 weeks, the treatment was well-tolerated and showed activity in advanced cancer patients with predominant liver metastases.

Spleen migrating dendritic cells primed with CC531 colon cancer antigen and LPS - is it a method to compromise liver metastases?

The anti-tumor vaccination is burdened by low recruitment rate of intravenously administered in vitro primed DC in liver metastases and lack of supplying them continuously in large numbers. Therefore, it seemed rational to create a model of in vivo vaccination with specifically primed splenic DC and cytotoxic T lymphocytes being continuously supplied to the liver vascular bed. The question we raised was whether anti-tumor immunized splenic DC flowing to liver metastases could adhere to and be cytotoxic to tumor cells. We immunized rats with CC531 tumor cells and stimulated them with Escherichia coli LPS. Subsequently, spleen DC-enriched population was isolated, its activation by LPS, adherence to CC531 cells and cytotoxicity were measured. Spleen cells home to the liver reaching it via splenic vein. These cells can be retrieved by simple washout of liver sinusoids (liver sinusoidal washout cells - LSWC). Their adherence to and cytotoxicity against CC531 cells were evaluated. Moreover, in vitro adherence of splenic DC-enriched cells and LSWC to CC531 liver tumor sections was measured. We found that in vivo immunization of splenic population containing DC, NK cells and lymphocytes with CC531 cells and stimulation with LPS activated these cells but did not significantly increase the cytotoxicity against CC531 cells. There was also no increase in cytotoxicity of LSWC. Adhesion of splenic DC and LWSC to liver CC531 metastases on cryosections was higher than to the adjacent liver tissue. However, it was more expressed on tumor stromal than neoplastic cells. The level of splenic Treg cells down-regulating immune response was found only slightly increased after immunization. Taken together, in the model of in vivo immunization against CC531 cells, low level of spleen DC and spleen-derived LSWC cytotoxicity as well as adherence rate to tumor cells were observed. More effective methods of immunizing splenic DC overcoming the suppressive mechanisms should be looked for.

Locoregional treatment of malignant hepatic tumors with biologic response modifiers

Locoregional delivery of biologic response modifiers (BRMs) to hepatic tumors is an appealing approach to increase the dwell time of BMRs, to minimize the systemic toxicity, and to induce local and possibly systemic immune responses against tumor cells. Previous clinical studies using this approach showed some encouraging results. However, a large-scale clinical trial is needed to prove the efficacy of locoregional BMR treatment in primary and metastatic hepatic tumors. Combination of various BRM agents with appropriate treatment modalities might further improve the efficacy of locoregional BMR treatment. Additionally, we need to collect more information regarding the host immune response and change in tumor microenvironment after delivering BMRs to hepatic tumors.

Immunoembolization of malignant liver tumors, including uveal melanoma, using granulocyte-macrophage colony-stimulating factor

PURPOSE

We conducted a phase I study to investigate the feasibility and safety of immunoembolization with granulocyte-macrophage colony-stimulating factor (GM-CSF; sargramostim) for malignant liver tumors, predominantly hepatic metastases from patients with primary uveal melanoma.

PATIENTS AND METHODS

Thirty-nine patients with surgically unresectable malignant liver tumors, including 34 patients with primary uveal melanoma, were enrolled. Hepatic artery embolization accompanied an infusion of dose-escalated GM-CSF (25 to 2,000 microg) given every 4 weeks. Primary end points included dose-limiting toxicity and maximum tolerated dose (MTD). Patients who completed two cycles of treatments were monitored for hepatic antitumor response. Survival rates of patients were also monitored.

RESULTS

MTD was not reached up to the dose level of 2,000 microg, and there were no treatment-related deaths. Thirty-one assessable patients with uveal melanoma demonstrated two complete responses, eight partial responses, and 10 occurrences of stable disease in their hepatic metastases. The median overall survival of intent-to-treat patients who had metastatic uveal melanoma was 14.4 months. Multivariate analyses indicated that female sex, high doses of GM-CSF (> or = 1,500 microg), and regression of hepatic metastases (complete and partial responses) were correlated to longer overall survival. Moreover, high doses of GM-CSF were associated with prolonged progression-free survival in extrahepatic sites.

CONCLUSION

Immunoembolization with GM-CSF is safe and feasible in patients with hepatic metastasis from primary uveal melanoma. Encouraging preliminary efficacy and safety results warrant additional clinical study in metastatic uveal melanoma.

Activation and dramatically increased cytolytic activity of tumor specific T lymphocytes after radio-frequency ablation in patients with hepatocellular carcinoma and colorectal liver metastases

AIM: To assess if a specific cytotoxic T cell response can be induced in patients with malignant liver tumors treated with radio-frequency ablation (RFA).

METHODS: Six Patients with liver metastases of colorectal cancer and 6 with hepatocellular carcinoma (HCC) underwent RFA. Blood was sampled before, 4 and 8 wk after RFA. Test antigens were autologous liver and tumor lysate obtained from each patient by biopsy. Peripheral T cell activation was assessed by an interferon gamma (IFNγ) secretion assay and flow cytometry. T cells were double-stained for CD4/CD8 and IFNγ to detect cytotoxic T cells. The ratio of IFNγ positive and IFNγ negative T cells was determined as the stimulation index (SI). To assess cytolytic activity, T cells were co-incubated with human CaCo colorectal cancer and HepG2 HCC cells and release of cytosolic adenylate kinase was measured by a luciferase assay.

RESULTS: Before RFA SI was 0.021 (± 0.006) for CD4⁺ and 0.022 (± 0.004) for CD8⁺ T cells against nonmalignant liver tissue and 0.018 (± 0.005) for CD4⁺ and 0.021 (± 0.004) for CD8⁺ cells against autologous tumor tissue. Four weeks after RFA SI against tumor tissue increased to 0.109 (± 0.005) for CD4⁺ and 0.11 (± 0.012) for CD8⁺ T cells against HCC, and to 0.115 (± 0.031) for CD4⁺ and 0.15 (± 0.02) for CD8⁺ cells for colorectal metastases (P < 0.0001). No increased SI was observed with nonmalignant tumor tissue at all time points. Before RFA cytolytic activity against the respective cancer cells was low with 2.62 (± 0.37) relative luminescence units (RLU), but rose more than 100 fold 4 and 8 wk after RFA. Spontaneous release was < 2% of maximum release in all experiments.

CONCLUSION: Patients with primary and secondary tumors of the liver show a significant tumor-specific cytotoxic T-cell stimulation with a dramatically increased tumor specific cytolytic activity of CD8⁺ T cells after RFA.

Antitumor Activity of IFN-λ in Murine Tumor Models

IFN-lambda 1, -lambda 2 and -lambda 3 have been discovered as the latest members of the class II cytokine family and shown to possess antiviral activity. Murine B16 melanoma and Colon26 cancer cells were transduced with mouse IFN-lambda to determine whether IFN-lambda possesses antitumor activity. Overexpression of IFN-lambda induced cell surface MHC class I expression and Fas/CD95 Ag, induced significant caspase-3/7 activity, and increased p21(Waf1/Cip1) and dephosphorylated Rb (Ser(780)) in B16 cells in vitro. IFN-lambda expression in tumor cell lines markedly inhibited s.c. and metastatic tumor formation in vivo compared with mock transfections (p < 0.05). Moreover, IFN-lambda expression induced lymphocytic infiltrates, and an Ab-mediated immune cell depletion assay showed that NK cells were critical to IFN-lambda-mediated tumor growth inhibition. Hydrodynamic injection of IFN-lambda cDNA successfully targeted liver metastatic foci of Colon26 cells, and moderately decreased the mortality of mice with tumors. IFN-lambda overexpression in the liver increased NK/NKT cells and enhanced their tumor-killing activity, and suggested the activation of innate immune responses. Thus, IFN-lambda induced both tumor apoptosis and NK cell-mediated immunological tumor destruction through innate immune responses. These findings suggested that local delivery of IFN-lambda might prove a useful adjunctive strategy in the clinical treatment of human malignancies.

Pharmacokinetics and in vitro and in vivo anti-tumor response of an interleukin-2-human serum albumin fusion protein in mice

PURPOSE

Albuleukin fusion protein is a recombinant human interleukin-2 (rIL-2) genetically fused to recombinant human serum albumin (rHSA). The pharmacokinetics and pharmacologic activity of Albuleukin were examined in mice to determine whether the fusion protein had the immunomodulatory and anti-tumor properties of rIL-2 as well as a prolonged serum half-life due to the rHSA.

METHODS

The effect of Albuleukin on lymphocyte proliferation, IL-2 receptor binding, and release of IFN-gamma from human NK cells were examined in vitro. For the pharmacokinetic analysis, Albuleukin and rIL-2 were administered intravenously (i.v.) and subcutaneously (s.c.) to BALB/c mice, both at a single dose of 500 microg/kg. The anti-tumor properties of Albuleukin were evaluated in a Renca tumor model in BALB/c mice and in a metastatic liver model of B16F10 melanoma in C57B1/6 mice. In the Renca tumor model, BALB/c mice were dosed intraperitoneally (i.p.) and s.c. with Albuleukin on days 12, 14, 16, 19, 21, and 23 and i.p. with rIL-2 daily for two periods of 5 days (days 10-14 and 17-21). In the B16 melanoma model, C57B1/6 mice were dosed s.c. with rIL-2 twice daily or Albuleukin every 48 h for 14 days.

RESULTS

In vitro, Albuleukin induced the proliferation of primary human and mouse T cells and B cells and primary human NK cells, competed with rIL-2 for binding to the IL-2 receptors, and induced the production of IFN-gamma from primary human NK cells. The s.c. bioavailability of Albuleukin was about 45% relative to the i.v. dose. Plasma half-life was prolonged and ranged from 6 to 8 h with Albuleukin, compared to 19-57 min with rIL-2. Total clearance of Albuleukin was about 50-fold slower than that of rIL-2 after i.v. dosing. In vivo, Albuleukin suppressed the growth of Renca tumors and induced a dense infiltration of CD4+ and CD8+ T cells. Both Albuleukin and rIL-2 significantly reduced the tumor burden in mice with hepatic B16F10 metastases. Albuleukin significantly reduced the incidence of residual macroscopic hepatic tumors, resulting in improved survival relative to controls and rIL-2.

CONCLUSION

Results from these studies suggest that the therapeutic efficacy of rIL-2 is improved in mice by prolonging its in vivo half-life through genetic fusion to albumin. Albuleukin, the fusion protein, had pronounced anti-tumor effects in Renca and hepatic melanoma tumor models without an increase in mortality. On the basis of its preclinical effects, Albuleukin was brought to the clinic to assess its therapeutic benefit in a variety of cancers.

Transfection of IL-2 and/or IL-12 genes into spleen in treatment of rat liver cancer

AIM: To test the efficacy of gene therapy in rat liver tumor.

METHODS: A retroviral vector GCIL12EIL2PN encoding human IL-2 (hIL-2) and mouse IL-12 (mIL-12) fused gene and its packaging cell were constructed. The packaging cell lines contained of IL-2 and/or IL-12 genes were injected intrasplenically to transfect splenocyte at different time. The therapeutic effect, immune function and toxic effect were evaluated.

RESULTS: The average survival times of the 4 groups using IL genes at days 1, 3, 5 and 7 after tumor implantation were 53.3 ± 3.7, 49.3 ± 4.2, 31.0 ± 2.1 and 24.3 ± 1.4 d respectively in IL-2/IL-12 fused gene group, 25.0 ± 2.5, 23.5 ± 2.0, 18.3 ± 2.4 and 12.0 ± 1.8 d respectively in IL-2 gene treatment group, and 39.0 ± 4.8, 32.0 ± 3.9, 23.0 ± 2.5 and 19.4 ± 2.1 d respectively in IL-12 gene treatment group (P < 0.01, n = 10). In the IL-12/IL-2 fused gene treatment group, 30% of rats treated at days 1 and 3 survived more than 60 d and serum mIL-12 and hIL-2 levels were still high at day 3 after treatment. Compared with IL alone, NK cell activity was strongly stimulated by IL-2/IL-12 gene. Microscopy showed that livers were infiltrated by a number of lymphocytes.

CONCLUSION: IL-2 and/or IL-12 genes injected directly into spleen increase serum IL-2 and IL-12 levels and enhance the NK cell activity, which may inhibit the liver tumor growth. The therapy of fused gene IL-2/IL-12 is of low toxicity and relatively high NK cell activity. Our data suggest that IL-2/IL-12 fused gene may be a safe and efficient gene therapy for liver tumor. The gene therapy should be administrated as early as possible.

Regional treatment options for patients with ocular melanoma metastatic to the liver

Ocular melanoma is the most common primary ocular malignancy and has a significant predilection for metastasis to the liver. More than 40% of patients have hepatic metastases present at initial diagnosis, and the liver becomes involved in up to 95% of individuals who develop metastatic disease. The median survival of patients after diagnosis of liver metastasis ranges from 2 to 7 months. Metastatic disease localized to the liver has proven to be resistant to most available chemotherapy and immunotherapy regimens. Recognition of the grave prognosis associated with liver metastasis from ocular melanoma has led to the evaluation of new regional treatment modalities primarily designed to control tumor progression in the liver, including hepatic arterial chemotherapy, hepatic artery chemoembolization, regional immunotherapy, isolated hepatic perfusion, and percutaneous hepatic perfusion. This article reviews the efficacy, outcomes, and morbidities of the multiple locoregional therapies available today.

Combined interventional therapies of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignancies in the world, responsible for an estimated one million deaths annually. It has a poor prognosis due to its rapid infiltrating growth and complicating liver cirrhosis. Surgical resection, liver transplantation and cryosurgery are considered the best curative options, achieving a high rate of complete response, especially in patients with small HCC and good residual liver function. In nonsurgery, regional interventional therapies have led to a major breakthrough in the management of unresectable HCC, which include transarterial chemoembolization (TACE), percutaneous ethanol injection (PEI), radiofrequency ablation (RFA), microwave coagulation therapy (MCT), laser-induced thermotherapy (LITT), etc. As a result of the technical development of locoregional approaches for HCC during the recent decades, the range of combined interventional therapies has been continuously extended. Most combined multimodal interventional therapies reveal their enormous advantages as compared with any single therapeutic regimen alone, and play more important roles in treating unresectable HCC.

New treatments with curative intent for metastatic colorectal liver cancer

Although surgical resection is the mainstay of therapy in metastatic colorectal liver cancer, < 10 - 15% of patients are suitable for resection. In addition, recurrence rates after resection may reach 75% in the first 2 years, of which 50% involve local recurrences in the liver. This has provided an impetus for the development of neoadjuvant and adjuvant protocols in the treatment of this malignancy, techniques concentrating on improving the residual liver functional reserve, as well as local tumour ablative therapies using radiofrequency and cryotherapy. A multimodal interdisciplinary approach is a pre-requisite when treating secondary liver tumours from colorectal cancer and should be concentrated in centres of reference. The development of such innovative modalities as preoperative downstaging in the absence of extrahepatic tumour disease, local tumour control and new adjuvant therapies has expanded the patient population thus providing the opportunity to treat patients with large or advanced stage colorectal liver tumours. The following is a review of some of the approaches currently being evaluated in the treatment of colorectal liver metastases.