First-Line Treatment for Advanced Hepatocellular Carcinoma: A Three-Armed Real-World Comparison.

Background and Aim: There are several existing systemic 1st- line therapies for advanced hepatocellular carcinoma (HCC), including atezolizumab/bevacizumab (Atez/Bev), sorafenib and lenvatinib. This study aims to compare the effectiveness of these three 1st-line systemic treatments in a real-world setting for HCC, focusing on specific patient subgroups analysis. Methods: A total of 177 patients with advanced HCC treated with Atez/Bev (n = 38), lenvatinib (n = 21) or sorafenib (n = 118) as 1st line systemic therapy were retrospectively analyzed and compared. Primary endpoints included objective response rate (ORR), progression-free survival (PFS) and 15-month overall survival (15-mo OS). Subgroups regarding liver function, etiology, previous therapy and toxicity were analyzed. Results: Atez/Bev demonstrated significantly longer median 15-month OS with 15.03 months compared to sorafenib with 9.43 months (p = 0.04) and lenvatinib with 8.93 months (p = 0.05). Similarly, it had highest ORR of 31.6% and longest median PFS with 7.97 months, independent of etiology. However, significantly superiority was observed only compared to sorafenib (ORR: 4.2% (p < 0.001); PFS: 4.57 months (p = 0.03)), but not comparing to lenvatinib (ORR: 28.6% (p = 0.87); PFS: 3.77 months (p = 0.10)). Atez/Bev also resulted in the longest PFS in patients with Child-Pugh A and ALBI 1 score and interestingly in those previously treated with SIRT. Contrary, sorafenib was non inferior in patients with impaired liver function. Conclusion: Atez/Bev achieved longest median PFS and 15-mo OS independent of etiology and particularly in patients with stable liver function or prior SIRT treatment. Regarding therapy response lenvatinib was non-inferior to Atez/Bev. Finally, sorafenib seemed to perform best for patients with deteriorated liver function.

Regulatory T Cell Inhibition by P60 Combined with Adenoviral AFP Transduced Dendritic Cells for Immunotherapy of Hepatocellular Carcinoma.

BACKGROUND & AIMS: Vaccination with tumor-associated antigen-pulsed dendritic cells leads to specific T-cell response against hepatocellular carcinoma. However, clinical response has been shown to be limited. High regulatory T-cell count is associated with poor prognosis and seems to mediate immune tolerance in hepatocellular carcinoma. Forkhead box P3-peptide inhibitor P60 has been shown to specifically inhibit regulatory T-cell function in murine models. Aim of this study was to investigate whether P60 can improve the immune response induced by vaccination with adenovirus-transduced dendritic cells expressing alpha-fetoprotein in subcutaneous and orthotopic murine models for hepatocellular carcinoma. METHODS: Mice developing subcutaneous or orthotopic HCC received daily treatment with P60 starting at different tumor stages. Additionally, mice were vaccinated twice with dendritic cells expressing alpha-fetoprotein. RESULTS: In a preventive setting prior to tumor engraftment, vaccination with alpha-fetoprotein-expressing dendritic cells significantly decreased tumor growth in a subcutaneous model (p = .0256), but no further effects were achieved by addition of P60. However, P60 enhanced the antitumoral effect of a vaccination with alpha-fetoprotein-expressing dendritic cells in established subcutaneous and orthotopic hepatocellular carcinoma characterized by high Treg levels (p = .011). CONCLUSION: In this study, we showed that vaccination with alpha-fetoprotein-expressing dendritic cells in combination with a specific inhibition of regulatory T-cells by using P60 leads to synergistic tumor inhibition and prolonged survival. This emphasizes the importance of regulatory T-cells inhibition for obtaining an effective antitumoral immune response in hepatocellular carcinoma.

Deficient Immune Response following SARS-CoV-2 Vaccination in Patients with Hepatobiliary Carcinoma: A Forgotten, Vulnerable Group of Patients.

Introduction: Data on immune response rates following vaccination for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in patients with hepatobiliary carcinoma (HBC) are rare. However, impaired immunogenicity must be expected due to the combination of chronic liver diseases (CLDs) with malignancy and anticancer treatment. Methods: In this prospective, longitudinal study, 101 patients were included, of whom 59 were patients with HBC under anticancer treatment. A cohort of patients with a past medical history of gastrointestinal cancer, of whom 28.6% had HBC without detectable active tumor disease having been off therapy for at least 12 months, served as control. Levels of SARS-CoV-2 anti-spike IgG, surrogate neutralization antibodies (sNABs), and cellular immune responses were compared. In uni- and multivariable subgroup analyses, risk factors for impaired immunogenicity were regarded. Data on rates and clinical courses of SARS-CoV-2 infections were documented. Results: In patients with HBC under active treatment, levels of SARS-CoV-2 anti-spike IgG were significantly lower (2.55 log10 BAU/mL; 95% CI: 2.33-2.76; p < 0.01) than in patients in follow-up care (3.02 log10 BAU/mL; 95% CI: 2.80-3.25) 4 weeks after two vaccinations. Antibody levels decreased over time, and differences between the groups diminished. However, titers of SARS-CoV-2 sNAB were for a longer time significantly lower in patients with HBC under treatment (64.19%; 95% CI: 55.90-72.48; p < 0.01) than in patients in follow-up care (84.13%; 95% CI: 76.95-91.31). Underlying CLD and/or liver cirrhosis Child-Pugh A or B (less than 8 points) did not seem to further impair immunogenicity. Conversely, chemotherapy and additional immunosuppression were found to significantly reduce antibody levels. After a third booster vaccination for SARS-CoV-2, levels of total and neutralization antibodies were equalized between the groups. Moreover, cellular response rates were balanced. Clinically, infection rates with SARS-CoV-2 were low, and no severe courses were observed. Conclusion: Patients with active HBC showed significantly impaired immune response rates to basic vaccinations for SARS-CoV-2, especially under chemotherapy, independent of underlying cirrhotic or non-cirrhotic CLD. Although booster vaccinations balanced differences, waning immunity was observed over time and should be monitored for further recommendations. Our data help clinicians decide on individual additional booster vaccinations and/or passive immunization or antiviral treatment in patients with HBC getting infected with SARS-CoV-2.

Comparison between regular additional endobiliary radiofrequency ablation and photodynamic therapy in patients with advanced extrahepatic cholangiocarcinoma under systemic chemotherapy.

Background and aims: Extrahepatic cholangiocarcinoma (eCCA) remains a malignancy with a dismal prognosis. The first-line standard of care includes systemic chemotherapy (SC) and biliary drainage through stenting. Endobiliary ablative techniques, such as photodynamic therapy (ePDT) and radio-frequency ablation (eRFA), have demonstrated feasibility and favorable survival data. This study aimed to compare the oncologic outcome in patients treated with SC and concomitant eRFA or ePDT. Method: All patients with eCCA were evaluated for study inclusion. Sixty-three patients receiving a combination of SC and at least one endobiliary treatment were retrospectively compared. Results: Patients were stratified into three groups: SC + ePDT (n = 22), SC + eRFA (n = 28), and SC + ePDT + eRFA (n = 13). The median overall survival (OS) of the whole cohort was 14.2 months with no statistically significant difference between the three therapy groups but a trend to better survival for the group receiving ePDT as well as eRFA, during SC (ePDT + SC, 12.7 months; eRFA + SC, 13.8 months; ePDT + eRFA + SC, 20.2 months; p = 0.112). The multivariate Cox regression and subgroup analysis highlighted the beneficial effect of eRFA on OS. Overall, combined therapy was well tolerated. Only cholangitis occurred more often in the SC + eRFA group. Conclusion: Additional endobiliary ablative therapies in combination with SC were feasible. Both modalities, eRFA and ePDT, showed a similar benefit in terms of survival. Interestingly, patients receiving both regimes showed the best OS indicating a possible synergism between both ablative therapeutic techniques.

Impaired immunogenicity after vaccination for SARS-CoV-2 in patients with gastrointestinal cancer: does tumor entity matter?

Background: SARS-CoV-2 immunogenicity in patients with gastrointestinal cancer (GI cancer) following second and third vaccination was analyzed. Methods: A total of 125 patients under active anticancer therapy or in follow-up care were included in this prospective study. Seroprevalence of SARS-CoV-2 anti-spike and surrogate neutralization antibodies (NABs) was measured. Results: Four weeks after second vaccination, adequate titers of SARS-CoV-2 anti-spike immunoglobulin G (IgG) [≥282.0 binding antibody units (BAU)/mL] were found in 62.2% of patients under treatment versus 96.3% of patients in follow-up care (P<0.01). Sufficient titers of SARS-CoV-2 surrogate NAB (≥85.0%) were found in 32.7% of patients under treatment versus 70.6% in follow-up care (P<0.01). Titers of SARS-CoV-2 anti-spike IgG were especially low in patients with colorectal cancer (CRC). For SARS-CoV-2 surrogate NAB, patients with hepatocellular carcinoma (HCC) and with pancreaticobiliary cancer showed the lowest titers (P<0.01). SARS-CoV-2 anti-spike IgG and SARS-CoV-2 surrogate NAB were associated with a correlation coefficient of 0.93. Reaching a titer of SARS-CoV-2 anti-spike IgG ≥482.0 BAU/mL, protective levels of SARS-CoV-2 surrogate NAB (≥85.0%) could be assumed. Following booster vaccination, all patients reached effective antibody titers. Conclusions: Patients with active GI cancer showed impaired immunogenicity after second SARS-CoV-2 vaccination which was overcome by booster vaccination. Our findings were tumor-related and pronounced in patients with CRC and HCC. Waning immunity over time and antibody escape phenomena by variant of concern Omicron must be considered in these especially vulnerable patients.

Second-line and third-line therapy with nanoliposomal irinotecan (nal-IRI) in pancreatic cancer: a single-center experience and review of literature.

Background: Prognosis of patients with pancreatic cancer is still extremely poor. First-line palliative therapies with FOLFIRINOX or gemcitabine/nab-paclitaxel have been established in the last decade. In the second-line, 5-FU/LV in combination with nanoliposomal irinotecan (nal-IRI) after gemcitabine has been shown to be effective. However, the use of nal-IRI as third-line therapy after FOLFIRINOX and gemcitabine-based chemotherapies is still controversial. In this study, we report about the use of 5-FU/LV + nal-IRI in a daily practice and analyze whether nal-IRI is an option as third-line therapy after FOLFIRINOX and gemcitabine/nab-paclitaxel. Methods: This is a single center retrospective analysis of patients with irresectable pancreatic cancer who were treated with 5-FU/LV and nal-IRI from 2017 to 2021 as second- or third-line palliative treatment. Overall survival (OS), progression-free survival (PFS) and toxicity were analyzed, and multivariate analysis was used to identify independent prognostic factors. Results: Twenty-nine patients receiving 5-FU/LV and nal-IRI were included in the analysis. The majority of patients (n=19) received 5-FU/nal-IRI as third-line therapy after pre-exposition to FOLFIRINOX and gemcitabine/nab-paclitaxel. Median OS and PFS were 9.33 months (95% CI: 3.37, 15.30) and 2.90 months (95% CI: 1.64, 4.16), respectively. Furthermore, patients receiving nal-IRI + 5-FU/LV as third-line treatment also showed some benefits, with no OS difference compared to second-line patients (9.33 vs. 10.27 months; HR: 1.85; 95% CI: 0.64, 5.41; P=0.253). Adverse effects were similar to reported trials. Conclusions: In our study, the use of 5-FU/nal-IRI in unselected patients with advanced pancreatic cancer showed similar OS, PFS and tolerance as randomized prospective phase II/III trials. Interestingly, the use of 5-FU/nal-IRI seemed to be beneficial in third-line therapy, despite a pre-exposure to non-liposomal irinotecan.

Perioperative therapy with FLOT4 significantly increases survival in patients with gastroesophageal and gastric cancer in a large real-world cohort.

In 2019, the FLOT4 protocol was established as the new standard for perioperative therapy in patients with locally advanced gastroesophageal and gastric cancer. Whether this protocol is beneficial in a real-world setting remains a question with limited answers to date. In our study, a large cohort of unselected patients treated with FLOT4 was analyzed and compared to protocols based on 5-FU/platinum derivative. This retrospective analysis included patients with locally advanced gastroesophageal and gastric cancer treated with perioperative FLOT or 5-FU/platinum derivative at University Hospital, Bonn between 2010 and 2022 in a curative setting (n = 99). Overall survival, disease-free survival, therapy response and therapy complications were analyzed. Patients treated with FLOT showed a statistically significant longer median overall survival of 57.8 vs 28.9 months (HR: 0.554, 95% CI: 0.317-0.969, P = .036). Moreover, pathological tumor regression (pTR) was significantly higher in the FLOT group compared to the 5-FU/platinum group (P = .001). Subgroup analysis showed a favorable survival benefit for the FLOT vs 5-FU/platinum derivate in patients with AEG and non-signet cell carcinoma. Overall, FLOT was tolerated well but CTCAE ≥3 grade neutropenia and diarrhea occurred more often within the FLOT group. Similar to the prospective phase II/III trials, FLOT4 was the best protocol for patients with locally advanced gastroesophageal and gastric cancer as perioperative therapy in terms of overall survival and pathological response rate compared to 5-FU/platinum derivative protocols. Interestingly, patients with gastroesophageal cancer benefitted more from this therapy. In contrast, patients with signet ring cells appear not to benefit from addition of docetaxel.

Efficacy and tolerability of fluorouracil, leucovorin, oxaliplatin and docetaxel (FLOT) in unselected patients with advanced gastric and gastroesophageal cancer: does age really matter?

PURPOSE: Fluorouracil, leucovorin, oxaliplatin and docetaxel (FLOT) regimen has shown strong efficacy as perioperative therapy for patients with locally advanced gastric (GC) and gastroesophageal (AEG) carcinoma. In the palliative situation, FLOT is recommended only for young fit patients. Data of efficacy and tolerability of FLOT in elderly patients are scarce and controversial. Thus, this study aimed to provide real-life experience of elderly patients with GC and AEG treated with FLOT as first-line palliative chemotherapy. METHODS: Patients with advanced or metastatic GC or AEG and treated with FLOT as first-line palliative therapy between 2010 and 2021 were analyzed. Patients were grouped into < 65 years old (n = 35) and ≥ 65 years old (n = 22) groups. Overall survival (OS), progression-free survival (PFS), feasibility and toxicity were analyzed. RESULTS: The median OS was 10.4 months with no significant difference between both groups (HR 0.86; 95% CI 0.48, 1.57; p = 0.632). The ECOG performance status showed powerful influence on OS in the subgroup analysis with median OS of 12.3 months for ECOG = 0 compared to 5.0 months for ECOG ≥ 1 (p = 0.015) as well as in multivariate analysis (HR 2.62; 95% CI 1.36, 5.04; p = 0.004). CONCLUSION: In the present study the ECOG performance status showed a stronger prognostic value than patient age in FLOT as first- line therapy in a real-life cohort with advanced and metastatic GC and AEG. The performance status should therefore be considered in the therapeutic decision making of elderly patients with GC and AEG.

Case Report: Sustained complete remission on combination therapy with olaparib and pembrolizumab in BRCA2-mutated and PD-L1-positive metastatic cholangiocarcinoma after platinum derivate.

Cholangiocarcinoma (CCA) still has a poor prognosis and remains a major therapeutic challenge. When curative resection is not possible, palliative systemic chemotherapy with gemcitabine and platinum derivate as first line followed by a 5-FU doublet combination as second line is the standard therapy. Recently, targeted therapy and immunotherapy have rapidly emerged as personalized therapeutic approaches requiring previous tumor sequencing and molecular profiling. BRCA mutations are well-characterized targets for poly (ADP-ribose) polymerase inhibitors (PARPi). However, BRCA gene mutations in CCA are rare and few data of PARPi in the treatment of CCA are available. Immunotherapy with programmed death receptor-1 (PD-1) has been shown to be effective in combination with chemotherapy or in PD-L1-positive CCA. However, data from immunotherapy combined with targeted therapy, including PARPi, are lacking. In this report, we present the case of a male patient with PD-L1-positive and BRCA2-mutated metastatic intrahepatic cholangiocarcinoma, who was treated with a combined therapy with PARP (PARPi), olaparib, and a PD-1 antibody, pembrolizumab, as second-line therapy after gemcitabine/platinum derivate failure. Combined therapy was able to induce a long-lasting complete remission for over 15 months. The combined therapy was feasible and well tolerated. Only mild anemia and immune-related thyroiditis were observed, which were easily manageable and did not result in discontinuation of olaparib and pembrolizumab. Conclusion: The presented case showed substantial clinical activity of a combination with olaparib/pembrolizumab in advanced BRCA2-mutated CCA. Thus, identifying targetable molecular signatures and combinations of targeted therapies with immunotherapy reveals a promising strategy to effectively treat patients with cholangiocarcinoma and should be considered after failure of standard chemotherapy.

Impact of regular additional endobiliary radiofrequency ablation on survival of patients with advanced extrahepatic cholangiocarcinoma under systemic chemotherapy.

Prognosis of patients with advanced extrahepatic cholangiocarcinoma (eCCA) is poor. The current standard first-line treatment is systemic chemotherapy (CT) with gemcitabine and a platinum derivate. Additionally, endobiliary radiofrequency ablation (eRFA) can be applied to treat biliary obstructions. This study aimed to evaluate the additional benefit of scheduled regular eRFA in a real-life patient cohort with advanced extrahepatic cholangiocarcinoma under standard systemic CT. All patients with irresectable eCCA treated at University Hospital Bonn between 2010 and 2020 were eligible for inclusion. Patients were stratified according to treatment: standard CT (n = 26) vs. combination of eRFA with standard CT (n = 40). Overall survival (OS), progression free survival (PFS), feasibility and toxicity were retrospectively analyzed using univariate and multivariate approaches. Combined eRFA and CT resulted in significantly longer median OS (17.3 vs. 8.6 months, p = 0.004) and PFS (12.9 vs. 5.7 months, p = 0.045) compared to the CT only group. While groups did not differ regarding age, sex, tumor stage and chemotherapy treatment regimen, mean MELD was even higher (10.1 vs. 6.7, p = 0.015) in the eRFA + CT group. The survival benefit of concomitant eRFA was more evident in the subgroup with locally advanced tumors. Severe hematological toxicities (CTCAE grades 3 - 5) did not differ significantly between the groups. However, therapy-related cholangitis occurred more often in the combined treatment group (p = 0.031). Combination of eRFA and systemic CT was feasible, well-tolerated and could significantly prolong survival compared to standard CT alone. Thus, eRFA should be considered during therapeutic decision making in advanced eCCA.

First Line and Second Line Chemotherapy in Advanced Cholangiocarcinoma and Impact of Dose Reduction of Chemotherapy: A Retrospective Analysis.

OBJECTIVE: Prognosis of patients with irresectable cholangiocarcinoma is still poor. The ABC-02 trial established the current first line (1L) standard systemic chemotherapy (CT) with gemcitabine/platinum derivate for advanced cholangiocarcinoma. However, the majority of patients needed therapy adaptions. Thus, the aim of this study was to evaluate 1L and second line (2L) therapy regimens and the impact of therapy adaptions in an unselected real-life cohort of patients with advanced cholangiocarcinoma. MATERIALS AND METHODS: This is a single institution retrospective analysis of patients with irresectable cholangiocarcinoma who were treated with gemcitabine/platinum derivate from 2010 to 2018. Overall survival (OS), progression-free survival (PFS) and toxicity were analyzed for all patients, especially with regard to CT de-escalation. RESULTS: Fifty-eight patients receiving gemcitabine/platinum derivate were included in the analysis. Median OS and PFS were 12.2 and 6.9 months. Interestingly, 41 patients (71%) needed therapy de-escalation. However, despite reduced CT exposition, there was no-significant difference in OS (10.8 months vs. 15.6 months, p = 0.127), and patients suffered from less adverse events during CT. 21 (36%) patients reached 2L CT, most often with FOLFIRI (57%). Survival beyond the end of 1L CT was 7.1 months with 2L CT vs. 2.9 months with BSC. CONCLUSION: In our study, the combination of gemcitabine/platinum derivate showed similar OS and PFS as randomized prospective phase II/III trials. Therapy regimen adaptions were needed in the majority of patients. However, individualized modifications of the therapy regimen allowed better tolerance as well as continuation of therapy and did not significantly influence median OS. Furthermore, our study revealed a potential survival benefit with 2L CT for selected patients.

Multimodal and systemic therapy with cabozantinib for treatment of recurrent hepatocellular carcinoma after liver transplantation: A case report with long term follow-up outcomes.

RATIONALE: Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) remains a major therapeutic challenge. In recent years, new molecular-targeted therapies, such as cabozantinib, have been approved for the treatment of advanced HCC. However, clinical experience with these new drugs in the treatment of HCC in the LT setting is very limited. PATIENT CONCERNS: In 2003, a 36-year-old woman was referred to the hospital with right upper abdominal pain. DIAGNOSIS: An initial ultrasound of the liver demonstrated a large unclear lesion of the left lobe of the liver. The magnet resonance imaging findings confirmed a multifocal inoperable HCC in a non-cirrhotic liver. Seven years after receiving a living donor LT, pulmonary and intra-hepatic recurrence of the HCC was radiologically diagnosed and histologically confirmed. INTERVENTIONS: Following an interdisciplinary therapy concept consisting of surgical, interventional-radiological (with radiofrequency ablation [RFA]) as well as systemic treatment, the patient achieved a survival of more than 10 years after tumor recurrence. As systemic first line therapy with sorafenib was accompanied by grade 3 to 4 toxicities, such as mucositis, hand-foot skin reaction, diarrhea, liver dysfunction, and hyperthyroidism, it had to be discontinued. After switching to cabozantinib from June 2018 to April 2020, partial remission of all tumor manifestations was achieved. The treatment of the remaining liver metastasis could be completed by RFA. The therapy with cabozantinib was well tolerated, only mild arterial hypertension and grade 1 to 2 mucositis were observed. Liver transplant function was stable during the therapy, no drug interaction with immunosuppressive drugs was observed. OUTCOMES: More than 10 years survival after recurrence of HCC after living-donor LT due to intensive multimodal therapy concepts, including surgery, RFA, and systemic therapy with cabozantinib in the second line therapy. LESSONS: In conclusion, this report highlights the tolerability and effectiveness of cabozantinib for the treatment of HCC recurrence after LT. We show that our patient with a late recurrence of HCC after LT benefitted from intensive multimodal therapy concepts, including surgery, RFA, and systemic therapy.

Alpha-Fetoprotein- and CD40Ligand-Expressing Dendritic Cells for Immunotherapy of Hepatocellular Carcinoma.

Dendritic cells (DC) as professional antigen presenting cells are able to prime T-cells against the tumor-associated antigen α-fetoprotein (AFP) for immunotherapy of hepatocellular carcinoma (HCC). However, a strong immunosuppressive tumor environment limits their efficacy in patients. The co-stimulation with CD40Ligand (CD40L) is critical in the maturation of DC and T-cell priming. In this study, the impact of intratumoral (i.t.) CD40L-expressing DC to improve vaccination with murine (m)AFP-transduced DC (Ad-mAFP-DC) was analyzed in subcutaneous (s.c.) and orthotopic murine HCC. Murine DC were adenovirally transduced with Ad-mAFP or Ad-CD40L. Hepa129-mAFP-cells were injected into the right flank or the liver of C3H-mice to induce subcutaneous (s.c.) and orthotopic HCC. For treatments, 106 Ad-mAFP-transduced DC were inoculated s.c. followed by 106 CD40L-expressing DC injected intratumorally (i.t.). S.c. inoculation with Ad-mAFP-transduced DC, as vaccine, induced a delay of tumor-growth of AFP-positive HCC compared to controls. When s.c.-inoculation of Ad-mAFP-DC was combined with i.t.-application of Ad-CD40L-DC synergistic antitumoral effects were observed and complete remissions and long-term survival in 62% of tumor-bearing animals were achieved. Analysis of the tumor environment at different time points revealed that s.c.-vaccination with Ad-mAFP-DC seems to stimulate tumor-specific effector cells, allowing an earlier recruitment of effector T-cells and a Th1 shift within the tumors. After i.t. co-stimulation with Ad-CD40L-DC, production of Th1-cytokines was strongly increased and accompanied by a robust tumor infiltration of mature DC, activated CD4+-, CD8+-T-cells as well as reduction of regulatory T-cells. Moreover, Ad-CD40L-DC induced tumor cell apoptosis. Intratumoral co-stimulation with CD40L-expressing DC significantly improves vaccination with Ad-mAFP-DC in pre-established HCC in vivo. Combined therapy caused an early and strong Th1-shift in the tumor environment as well as higher tumor apoptosis, leading to synergistic tumor regression of HCC. Thus, CD40L co-stimulation represents a promising tool for improving DC-based immunotherapy of HCC.

Induction of cytotoxic effector cells towards cholangiocellular, pancreatic, and colorectal tumor cells by activation of the immune checkpoint CD40/CD40L on dendritic cells.

INTRODUCTION: Gastrointestinal (GI) malignancies, such as cholangiocarcinoma, pancreatic carcinoma, and metastatic colorectal carcinoma, have a poor prognosis and effective therapeutic approaches are still challenging. Checkpoint inhibition with PD-1 or PDL-1 antibodies revealed promising results in different tumor entities; however, only few patients with GI tumors can potentially benefit from PD1/PDL1 inhibiting immunotherapy. Further immunotherapeutic strategies for GI malignancies are urgently needed. The aim of this study was to demonstrate that in vitro activation of the immune checkpoint CD40/CD40L can improve DC action towards bile duct, pancreas, and colorectal carcinoma. METHODS: Human DC were isolated from buffy coats from healthy donors, pulsed with tumor lysates and then transduced with adenoviruses encoding human CD40L (Ad-hCD40L). Using transwell assays, the effects of (m)CD40L on DC immunoactivation compared to (s)CD40L were analyzed. Surface marker and cytokine/chemokine expression were measured by flow cytometry, ELISA and cytokine arrays. Capacity of Ad-hCD40L-transduced DC to induce tumor-specific effector cells was tested using MTT proliferation assay and cytotoxicity assays. Apoptosis induction on tumor cells after culturing with supernatants of Ad-hCD40L-transduced DC was analyzed by flow cytometry. RESULTS: Ad-hCD40L transduction induced a high expression of (s)CD40L and (m)CD40L on DC and seemed to induce a strong cellular CD40/CD40L interaction among DC, leading to the formation of cell aggregates. Due to the CD40/CD40L interaction, a significant upregulation of DC maturation markers and a Th1-shift on cytokines/chemokines in the supernatant of DC were achieved. Interestingly, a pure Th1-shift was only achieved, when a cellular CD40/CD40L interaction among DC took place. (s)CD40L induced almost no upregulation of maturation markers and rather resulted in a Th2-cytokine expression, such as IL-10. Correspondingly, (m)CD40L-expressing DC led to significant proliferation and stimulation of tumor-specific effector cells with increased cytotoxicity towards pancreatic, bile duct and colorectal tumor cells. Supernatants of Ad-hCD40L-transduced DC could also induce apoptosis in the different tumor cells in vitro. CONCLUSION: Stimulation of the immune checkpoint CD40L/CD40 by endogenous expression of (m)CD40L provokes a cellular interaction, which increases the immunomodulatory capacity of DC. A Th1 cytokine/chemokine expression is induced, leading to a significant proliferation and enabling cytotoxicity of effector cells towards human bile duct, pancreatic and colorectal tumor cells. The present data point to the promising approach for DC-based immunotherapy of gastrointestinal malignances by activating the CD40/CD40L immune checkpoint.

Programmed cell death protein 1 (PD-1)-inhibition in hepatocellular carcinoma (HCC): a single center experience.

BACKGROUND: The prognosis for advanced Hepatocellular carcinoma (HCC)is still very poor. Despite initial usefulness of immune checkpoint inhibitor (PD-1), phase 3 trials failed to show significant benefit of PD-1 inhibition with nivolumab or pembrolizumab in the first and second line therapy of HCC. Clinical evidence of PD-1 inhibition in patients with advanced and heavily pretreated HCC outside clinical trials is extremely limited. In this study, we analyzed the clinical experience with PD-1 inhibition in patients with heavily pretreated HCC. METHODS: Between May 2016 and January 2019 14 patients with advanced and heavily pretreated HCC were treated with nivolumab or pembrolizumab at the University Hospital Bonn, Germany. Base line characteristics prior to immunotherapy, immunohistochemistry of different immunological markers, beneficial outcome and safety were recorded and retrospectively analyzed. RESULTS: Immunotherapy with PD-1 inhibition was well tolerated and resulted in significant clinical benefit as last line therapy. Median overall survival (OS) was 6.6 months (95%CI:3.9-11.8), progression-free survival (PFS) was 5.3 months (95%CI:2.4-11.7) and overall response rate (ORR) was 30.8%. One patient reached a complete remission. CONCLUSIONS: Despite numerous pretreatments, PD-1 inhibition was well tolerated and showed clinical benefit in patients with heavily pretreated HCC.

Physiological relevance of sphingolipid activator proteins in cultured human fibroblasts.

The physiological degradation of several membrane-bound glycosphingolipids (GSLs) by water-soluble lysosomal exohydrolases requires the assistance of sphingolipid activator proteins (SAPs). Four of these SAPs are synthesized from a single precursor protein (prosaposin). Inherited deficiency of this precursor results in a rare disease in humans with an accumulation of ceramide (Cer) and glycolipids such as glucosylceramide and lactosylceramide (LacCer). In a previous study, we have shown that human SAP-D stimulates the lysosomal degradation of Cer in precursor deficient cells. In order to study the role of SAPs (or saposins) A-D in cellular GSL catabolism, we recently investigated the catabolism of exogenously added [(3)H]labeled ganglioside GM1, Forssman lipid, and endogenously [(14)C]labeled GSLs in SAP-precursor deficient human fibroblasts after the addition of recombinant SAP-A, -B, -C and -D. We found that activator protein deficient cells are still able to slowly degrade gangliosides GM1 and GM3, Forssman lipid and globotriaosylceramide to a significant extent, while LacCer catabolism critically depends on the presence of SAPs. The addition of either of the SAPs, SAP-A, SAP-B or SAP-C, resulted in an efficient hydrolysis of LacCer.