CD4+ T cell-derived IL-22 enhances liver metastasis by promoting angiogenesis.

Metastasis is a cancer-related systemic disease and is responsible for the greatest mortality rate among cancer patients. Interestingly, the interaction between the immune system and cancer cells seems to play a key role in metastasis formation in the target organ. However, this complex network is only partially understood. We previously found that IL-22 produced by tissue resident iNKT17 cells promotes cancer cell extravasation, the early step of metastasis. Based on these data, we aimed here to decipher the role of IL-22 in the last step of metastasis formation. We found that IL-22 levels were increased in established metastatic sites in both human and mouse. We also found that Th22 cells were the key source of IL-22 in established metastasis sites, and that deletion of IL-22 in CD4+ T cells was protective in liver metastasis formation. Accordingly, the administration of a murine IL-22 neutralizing antibody in the establishment of metastasis formation significantly reduced the metastatic burden in a mouse model. Mechanistically, IL-22-producing Th22 cells promoted angiogenesis in established metastasis sites. In conclusion, our findings highlight that IL-22 is equally as important in contributing to metastasis formation at late metastatic stages, and thus, identify it as a novel therapeutic target in established metastasis.

A single-center, open-label, randomized cross-over study to evaluate the pharmacokinetics and bioavailability of once-daily prolonged-release formulations of tacrolimus in de novo liver transplant recipients.

BACKGROUND: The narrow therapeutic window of tacrolimus (Tac) requires intense drug monitoring to achieve adequate efficacy while minimizing dose-related toxicities. Once-daily formulations of Tac (LCP-Tac and PR-Tac) have been recently designed for higher bioavailability and a more consistent exposure over time, as opposed to the twice-daily, administered immediate-release formulation of Tac (IR-Tac). METHODS: This single-center, open-label, randomized cross-over pharmacokinetic (PK) study compares extended-release LCP-Tac with the prolonged-release formulation of tacrolimus (PR-Tac) in adult de novo liver transplant recipients. Eligible patients were screened and randomized 1:1 to the two treatment arms up to 30 days after liver transplantation. Patients were administered either LCP-Tac or PR-Tac for 14 days followed by another 14-day time interval of the other once-daily Tac medication. A 24hr-PK profile was obtained at the end of each time interval. RESULTS: Nine patients (45%) completed the study resulting in a total of 18 Tac PK profiles. Overall, the profile of the mean concentrations indicated a flattened kinetic of LCP-Tac compared to PR-Tac, especially in the first 3 h after drug intake. The average cumulative dose per day to achieve equivalent trough levels was approximately 25% lower for LCP-Tac (8.7 mg) than for PR-Tac (11.7 mg). LCP-Tac resulted in a longer tmax and fewer peak-to-trough fluctuations compared to PR-Tac. CONCLUSION: Despite methodological weaknesses that limit the conclusions, we have found a more consistent drug exposure for LCP-Tac in de novo LT recipients. LCP-Tac demonstrated a greater bioavailability compared to PR-Tac.

Dual antibody induction and de novo use of everolimus enable low-dose tacrolimus with early corticosteroid withdrawal in simultaneous pancreas-kidney transplantation.

BACKGROUND: To be an optimal immunosuppressive regimen after simultaneous pancreas kidney transplantation (SPK), low dose calcineurin inhibitor and early withdrawal of corticosteroids are desired. METHODS: Immunosuppressive regimen as such has been conducted consecutively in SPK recipients since 2009 in authors' institute. In addition to tacrolimus in low trough level and early corticosteroid withdraw, dual induction with basiliximab and low-dose thymoglobulin in combination with everolimus are the important components of the protocol. RESULTS: 25 consecutive primary SPK recipients were included in the study. Lymphocyte depletion by low dose thymoglobulin was limited to two weeks, and CD25 coating with basiliximab was detectable for 4 weeks. The BPAR within the first 12 months was 13%. During a median follow-up of 58 months, new-onset diabetes mellitus and renal function deterioration were rare events. No cytomegalovirus activation was encountered. The patients, pancreas and kidney graft survival at 1-year and 5-year was 100% and 94.4%, 95.8% and 95.8%, 100% and 100% respectively.

Outcome following right-extended split liver transplantation in the recent transplant era: Single-center analysis of a German transplant center.

INTRODUCTION: When a sufficiently high-quality liver is available, classic liver graft splitting is performed. In such cases, a small child receives the left-lateral split graft, with subsequent transplantation of the right-extended graft in an adult. METHODS: We analyzed 64 patients who received right-extended liver grafts from 2007 to 2015, and compared outcomes between cases of external vs in-house graft splitting. RESULTS: We found excellent donor data and comparable recipient characteristics. Cold ischemic time was significantly longer for external (14 ± 2 hours; n = 38) vs internal (12 ± 2 hours; n = 26) liver graft splitting. Compared to the internal splitting group, the external liver graft splitting group showed significantly reduced 1- and 5-year patient survival (100% vs 84%; P = .035) and higher rates of biliary (24% vs 12%) and vascular (8% vs 0%) complications. CONCLUSIONS: The outcomes following right-extended split LTX are disappointing given the excellent organ quality. External liver graft splitting was associated with worse outcome and surgical complication rates. This may be related to the prolonged cold ischemic time due to twofold transportation, as well as the ignorance of the splitting procedure details and related pitfalls.

Application of ICP-MS and HPLC-ICP-MS for diagnosis and therapy of a severe intoxication with hexavalent chromium and inorganic arsenic.

ICP-MS and HPLC-ICP-MS were applied for diagnosis and therapeutic monitoring in a severe intoxication with a liquid containing hexavalent chromium (Cr(VI)) and inorganic arsenic (iAs). In this rare case a liver transplantation of was considered as the only chance of survival. We developed and applied methods for the determination of Cr(VI) in erythrocytes and total chromium (Cr) and arsenic (As) in blood, plasma, urine and liver tissue by ICP-MS. Exposure to iAs was diagnosed by determination of iAs species and their metabolites in urine by anion exchange HPLC-ICP-MS. Three days after ingestion of the liquid the total Cr concentrations were 2180 and 1070µg/L in whole blood and plasma, respectively, and 4540µg/L Cr(VI) in erythrocytes. The arsenic concentration in blood was 206µg/L. The urinary As species concentrations were <0.5, 109, 115, 154 and 126µg/L for arsenobetaine, As(III), As(V), methylarsonate (V) and dimethylarsinate (V), respectively. Total Cr and As concentrations in the explanted liver were 11.7 and 0.9mg/kg, respectively. Further analytical results of this case study are tabulated and provide valuable data for physicians and toxicologists.

Incidence of BK polyomavirus infection after kidney transplantation is independent of type of immunosuppressive therapy.

BACKGROUND: BK polyomavirus (BKV) infection and BKV nephropathy (BKVN) are risk factors for allograft function and survival. METHODS: We retrospectively analyzed BK viremia and BKVN in 348 patients who received a kidney transplantation donated after brain death (n=232) or living donation (n=116) between 2008 and 2013. A total of 266 patients were treated with standard immunosuppression consisting of basiliximab induction, calcineurin inhibitor (CNI), and mycophenolic acid (MPA, n=219) or everolimus (n=47); 82 patients received more intense immunosuppression with lymphocyte depletion, CNI and MPA (n=38) or everolimus (n=44). RESULTS: BK viremia occurred in 33 (9.5%) patients in the first year and in 7 (2.0%) recipients in the second year after transplantation. BKVN occurred in 4 (1.1%) patients in the first year. Donor and recipient age, diabetes, previous transplantation, and type of transplantation (donated after brain death vs living donation) were not risk factors (P>.05). BK incidence did not differ depending on induction or maintenance immunosuppression. CONCLUSION: Incidence of BK viremia is independent of recipient characteristics, type of transplantation as well as induction and maintenance immunosuppression.

Early Initiation of Everolimus After Liver Transplantation: A Single-Center Experience.

BACKGROUND: Evidence relating to early everolimus use after liver transplantation remains limited. MATERIAL AND METHODS: Ninety-one adult patients undergoing liver transplantation at our center during 2007-2012 in whom everolimus therapy was initiated <3 months post-transplant were analyzed retrospectively. Everolimus was started on days 1-5 in 50 patients (group 1) and after day 5 in 41 patients (group 2). Most patients continued to receive low-dose cyclosporine (59.3%, target 50-80 ng/ml) or low-dose tacrolimus (25.3%; target 3-5 ng/ml). Mean follow-up was 4.6 years. RESULTS: One-, three- and five-year patient survival rates were 80.5%, 74.2%, and 70.5%, respectively, and did not differ between groups 1 and 2. Six patients (6.6%) developed biopsy-proven acute rejection after a median of 47 days (range 27-356 days). Everolimus was discontinued due to adverse events in 21 patients (23.1%). Incisional hernia repair occurred in 14.0% and 9.4% of patients in group 1 and 2, respectively. Renal function remained stable during follow-up, despite poor baseline function. CONCLUSIONS: Everolimus with very low-dose calcineurin inhibitor given immediately after liver transplantation appears safe and effective, achieving a low rejection rate with well-preserved renal function.

De novo mTOR inhibitor-based immunosuppression in ABO-incompatible kidney transplantation.

ABO-incompatible (ABOi) kidney transplantation (KTx) has become an accepted therapeutic option in renal replacement therapy for patients without a blood group-compatible living donor. Using different desensitization strategies, most centers apply B-cell depletion with rituximab and maintenance immunosuppression (IS) with tacrolimus and mycophenolic acid. This high load of total IS leads to an increased rate of surgical complications and virus infections in ABOi patients. Our aim was to establish ABOi KTx using an immunosuppressive regimen, which is effective in preventing acute rejection without increasing the risk for viral infections. Therefore, we selected a de novo immunosuppressive protocol with low-dose calcineurin inhibitor and the mTOR inhibitor everolimus for our ABOi program. Here, we report the first 25 patients with a complete three-yr follow-up treated with this regimen. Three-yr patient survival and graft survival were 96% and 83%. The rate of acute T-cell-mediated rejections was low (12%). Cytomegalovirus (CMV) infection was evident in one patient only (4%). Surgical complications were common (40%), but mild in 80% of cases. We demonstrate that ABOi KTx with a de novo mTOR inhibitor-based regimen is feasible without severe surgical or immunological complications and a low rate of viral infections.

Prolonged dormancy of human liposarcoma is associated with impaired tumor angiogenesis.

The disease state of cancer appears late in tumor development. Before being diagnosed, a tumor can remain for prolonged periods of time in a dormant state. Dormant human cancer is commonly defined as a microscopic tumor that does not expand in size and remains asymptomatic. Dormant tumors represent an early stage in tumor development and may therefore be a potential target for nontoxic, antiangiogenic therapy that could prevent tumor recurrence. Here, we characterize an experimental model that recapitulates the clinical dormancy of human tumors in mice. We demonstrate that these microscopic dormant cancers switch to the angiogenic phenotype at a predictable time. We further show that while angiogenic liposarcomas expand rapidly after inoculation of tumor cells in mice, nonangiogenic dormant liposarcomas remain microscopic up to one-third of the normal severe combined immune deficiency (SCID) mouse life span, although they contain proliferating tumor cells. Nonangiogenic dormant tumors follow a similar growth pattern in subcutaneous (s.c.) and orthotopic environments. Throughout the dormancy period, development of intratumoral vessels is impaired. In nonangogenic dormant tumors, small clusters of endothelial cells without lumens are observed early after tumor cell inoculation, but the nonangiogenic tumor cannot sustain these vessels, and they disappear within weeks. There is a concomitant decrease in microvessel density, and the nonangiogenic dormant tumor remains harmless to the host. In contrast, microvessel density in tumors increases rapidly after the angiogenic switch and correlates with rapid expansion of tumor mass. Both tumor types cultured in vitro contain fully transformed cells, but only cells from the nonangiogenic human liposarcoma secrete relatively high levels of the angiogenesis inhibitors thrombospondin-1 and TIMP-1. This model suggests that as improved blood or urine molecular biomarkers are developed, the microscopic, nonangiogenic, dormant phase of human cancer may be vulnerable to antiangiogenic therapy years before symptoms, or before anatomical location of a tumor can be detected, by conventional methods.

Angiogenesis inhibition by angiostatin, endostatin and TNP-470 prevents cyclophosphamide induced cystitis.

Angiogenesis, the induction of vessel growth is involved in numerous physiological and pathological processes. While the anti-tumor effect of angiogenesis inhibitors has been extensively investigated in malignant tumors, there is very little information on the effect of angiogenesis inhibitors on inflammation induced angiogenesis. In this report, we utilized a murine model of acute chemically induced cystitis to investigate the ability of three different angiogenesis inhibitors, angiostatin, endostatin and TNP-470, to inhibit the angiogenesis stimulated by this injury. We demonstrate herein, that prophylactic application of the angiogenesis inhibitors led to a significant reduction of each of the inflammatory parameters that were measured. We conclude that anti-angiogenic therapy with angiostatin, endostatin and TNP-470 inhibits inflammation associated angiogenesis induced in this model. We also propose that anti-angiogenic agents may serve as a valuable addition to a standard cyclophosphamid chemotherapy regimen to help reduce the chemotherapy-related side effects while potentially adding an anti-tumor effect.

Portal vein embolization vs. portal vein ligation for induction of hypertrophy of the future liver remnant.

The objective of this study was to assess the efficacy of right portal vein embolization (PVE) vs. right portal vein ligation (PVL) for induction of hypertrophy of the left lateral liver lobe before extended right hepatectomy. Thirty-four patients with primary or secondary liver tumors and estimated remnant functional liver parenchyma of less than 0.5% of body weight underwent either right PVE (transcutaneous, n = 10; transileocolic, n = 7) or right PVL (n = 17). Liver volume was assessed by CT scan before occlusion of the right portal vein and prior to resection. There were no deaths. The morbidity rate in each group was 5.8% (PVE, 1 abscess; PVL, 1 bile leak). The increase in liver volume was significantly higher after PVE compared with PVL (188 +/- 81 ml vs. 123 +/- 58 ml) (P = 0.012). Postoperative hospital stay was significantly shorter after PVE in comparison to PVL (4 +/- 2.9 days vs. 8.1 +/- 5.1 days; P < 0.01). Curative liver resection was performed in 10 of 17 patients after PVE and 11 of 17 patients after PVL. PVE and PVL were found to be feasible and safe methods of increasing the remnant functional liver volume and achieving resectability for extended liver tumors. PVE results in a significantly more efficient increase in liver volume and a shorter hospital stay.

Persistence of microscopic human cancers in mice: alterations in the angiogenic balance accompanies loss of tumor dormancy.

Some human tumor lines do not form visible tumors when inoculated into immunosuppressed mice. The fate of these human tumor lines was followed by transfecting them with green fluorescence protein before inoculating them into mice. Although the tumor lines failed to grow progressively, they formed small dormant microscopic foci maintained at constant mass by balanced proliferation and apoptosis. Transfecting the cells with either VEGF165 or activated c-Ha-ras induced loss of dormancy, which correlated with a shift in the angiogenic balance toward increased vascularity with reduced tumor cell apoptosis. These results support a model in which loss of dormancy is controlled in part by a switch to an angiogenic phenotype. These tumor lines may serve as models for investigating the cellular mechanisms controlling dormancy and identifying those factors that promote the loss of balanced proliferation and apoptosis. Finally, these models may prove useful in the design and testing of therapies directed toward eradicating dormant tumors and preventing tumor recurrence.