Non-IL-2-blocking anti-CD25 antibody inhibits tumor growth by depleting Tregs and has synergistic effects with anti-CTLA-4 therapy

CD25, also known as the interleukin-2 receptor α chain (IL-2Rα), is highly expressed on regulatory T cells (Tregs), but relatively lower on effector T cells (Teffs). This makes it a potential target for Treg depletion, which can be used in tumor immunotherapy. However, marketed anti-CD25 antibodies (Basiliximab and Daclizumab) were originally developed as immunosuppressive drugs to prevent graft rejection, because these antibodies can block IL-2 binding to CD25 on Teffs, which in turn destroys the function of Teffs. Recent studies have shown that non-IL-2-blocking anti-CD25 antibodies have displayed exciting antitumor effects. Here, we screened out a non-IL-2-blocking anti-CD25 monoclonal antibody (mAb) 7B7 by hybridoma technology, and confirmed its antitumor activity via depleting Tregs in a CD25 humanized mouse model. Subsequently, we verified that the humanized 7B7, named as h7B7-15S, has comparable activities to 7B7, and that its Treg depletion is further increased when combined with anti-CTLA-4, leading to enhanced remodeling of the tumor immune microenvironment. Moreover, our findings reveal that the Fab form of h7B7-15S has the ability to deplete Tregs, independent of the Fc region. Taken together, our studies expand the application of anti-CD25 in tumor immunotherapy and provide insight into the underlying mechanism.

Effect of emodin combined with cisplatin on the invasion and migration of HepG2 hepatoma cells

Cisplatin is the leading chemotherapy agent for advanced liver cancer. However, the resistance to cisplatin in liver cancer reduces its efficacy. A potential strategy to increase its effectiveness and reduce toxicity is to combine cisplatin with 1,3,8-trihydroxy-6-methylanthraquinone (emodin). In this study, we examined the effects of emodin combined with cisplatin on the invasion and migration of HepG2 cells and analyzed the role of emodin. The effects of cisplatin, emodin and their combination were assessed in HepG2 cells. Proliferation, invasion and migration of HepG2 cells were examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT), scar and Transwell assays. The gelatinase spectrum and an ELISA detected the expression of matrix metallopeptidase 2 (MMP-2) and matrix metallopeptidase 9 (MMP-9). The expression of E-cadherin and vimentin was detected by immunofluorescence and Western blots. Emodin inhibited cell invasion and migration in HepG2 hepatoma cells, increased E-cadherin expression, decreased vimentin, MMP-2, and MMP-9 expression. The combination of emodin and cisplatin-induced a more significant effect in a dose-dependent manner. In this study, we found that emodin inhibited hepatocellular carcinoma (HCC) metastasis. Compared with either cisplatin or emodin alone, the combination of both showed a more significant synergistic effect. Emodin can enhance the sensitivity of HepG2 HCC cells to cisplatin by inhibiting epithelial-mesenchymal transition, and thus, play a role in preventing recurrence and metastasis in HCC.

Filamin A is overexpressed in non-alcoholic steatohepatitis and contributes to the progression of inflammation and fibrosis

Non-alcoholic steatohepatitis (NASH) is a chronic and progressive liver disease characterized by steatosis, inflammation, and fibrosis. Filamin A (FLNA), an actin-binding protein, is involved in various cell functions, including the regulation of immune cells and fibroblasts. However, its role in the development of NASH through inflammation and fibrogenesis is not fully understood. In this study, we found that FLNA expression was increased in liver tissues of patients with cirrhosis and mice with non-alcoholic fatty liver disease (NAFLD)/NASH and fibrosis. Immunofluorescence analysis showed that FLNA was primarily expressed in macrophages and hepatic stellate cells (HSCs). Knocking down of FLNA by specific shRNA in phorbol-12-myristate-13-acetate (PMA)-derived THP-1 macrophages reduced lipopolysaccharide (LPS)-stimulated inflammatory response. The decreased mRNA levels of inflammatory cytokines and chemokines and suppression of the STAT3 signaling were observed in FLNA-downregulated macrophages. In addition, knockdown of FLNA in immortalized human hepatic stellate cells (LX-2 cells) resulted in decreased mRNA levels of fibrotic cytokines and enzymes involved in collagen synthesis, as well as increased levels of metalloproteinases and pro-apoptotic proteins. Overall, these results suggest that FLNA may contribute to the pathogenesis of NASH through its role in the regulation of inflammatory and fibrotic mediators.

Use of telemedicine in the postoperative assessment of proctological patients: a case-control study

BACKGROUND

Telemedicine is emerging as an easy way to communicate between patients and surgeons. Use of telemedicine increased during the coronavirus disease 2019 (COVID-19) pandemic. WhatsApp is one of the most common smartphone applications for user-friendly telemedicine. The aim of this study was to evaluate patient perception of health quality and positive outcomes using a diary sent by the patient to the surgeon via WhatsApp during the first post-discharge week after proctologic surgery.

METHODS

Ninety-eight patients discharged after proctologic surgery at the Israelite Hospital of Rome and the AOU Policlinico Umberto I of Rome in 1 January-31 December 2019 were divided into two groups: the WhatsApp group (group A), (n = 36) and the no WhatsApp group (group B) (n = 62). Group A patients received a protocol to follow for the day-by-day diary during the first post-discharge week and sending it by WhatsApp to the surgeon. Group B patients only received recommendations at discharge. The tool's usefulness was assessed by a questionnaire one month after the intervention.

RESULTS

The two groups were homogeneous for age, sex, schooling, employment, and proctologic pathology. Group A patients had less difficulty keeping a diary (p < 0.0001). Group A patients had the perception of better follow-up post-discharge (p = 0.002). The use of the diary sent by WhatsApp significantly improved the perception of positive post-intervention outcomes (p = 0.007). WhatsApp was the only independent predictor of perception of post-surgical positive outcomes (odds ratio = 4.06; 95% CI 1.35-12.24; p = 0.01).

CONCLUSIONS

The use of WhatsApp in the post-discharge period improves the lifestyle quality of the patients and their perception of the safety and quality of care received.

FTL004, an anti-CD38 mAb with negligible RBC binding and enhanced pro-apoptotic activity, is a novel candidate for treatments of multiple myeloma and non-Hodgkin lymphoma

Anti-CD38 monoclonal antibodies (mAbs), daratumumab, and isatuximab have represented a breakthrough in the treatment of multiple myeloma (MM). Recently, CD38-based mAbs were expected to achieve increasing potential beyond MM, which encouraged us to develop new anti-CD38 mAbs to meet clinical needs. In this study, we developed a novel humanized anti-CD38 antibody, FTL004, which exhibited enhanced pro-apoptotic ability and negligible binding to red blood cells (RBCs). FTL004 presented a better ability to induce direct apoptosis independent of Fc-mediated cross-linking against lymphoma and MM cell lines as well as primary myeloma cells derived from MM patients. For instance, FTL004 induced RPMI 8226 cells with 55% early apoptosis cells compared with 20% in the isatuximab-treated group. Of interest, FTL004 showed ignorable binding to CD38 on human RBCs in contrast to tumor cells, even at concentrations up to 30 μg/mL. Furthermore, with an engineered Fc domain, FTL004 displayed stronger antibody-dependent cellular cytotoxicity (ADCC) against CD38+ malignant cells. In vivo MM and non-Hodgkin lymphoma tumor xenograft models showed that FTL004 possessed an effective anti-tumor effect. Cryo-electron microscopy structure resolved two epitope centers of FTL004 on CD38: one of which was unique while the other partly overlapped with that of isatuximab. Taken together, FTL004 distinguishes it from other CD38 targeting mAbs and represents a potential candidate for the treatment of MM and non-Hodgkin lymphoma.

How useful is the machine perfusion in liver transplantation? An answer from a national survey

Machine perfusion (MP) has been shown worldwide to offer many advantages in liver transplantation, but it still has some gray areas. The purpose of the study is to evaluate the donor risk factors of grafts, perfused with any MP, that might predict an ineffective MP setting and those would trigger post-transplant early allograft dysfunction (EAD). Data from donors of all MP-perfused grafts at six liver transplant centers have been analyzed, whether implanted or discarded after perfusion. The first endpoint was the negative events after perfusion (NegE), which is the number of grafts discarded plus those that were implanted but lost after the transplant. A risk factor analysis for NegE was performed and marginal grafts for MP were identified. Finally, the risk of EAD was analyzed, considering only implanted grafts. From 2015 to September 2019, 158 grafts were perfused with MP: 151 grafts were implanted and 7 were discarded after the MP phase because they did not reach viability criteria. Of 151, 15 grafts were lost after transplant, so the NegE group consisted of 22 donors. In univariate analysis, the donor risk index >1.7, the presence of hypertension in the medical history, static cold ischemia time, and the moderate or severe macrovesicular steatosis were the significant factors for NegE. Multivariate analysis confirmed that macrosteatosis >30% was an independent risk factor for NegE (odd ratio 5.643, p = 0.023, 95% confidence interval, 1.27–24.98). Of 151 transplanted patients, 34% experienced EAD and had worse 1- and 3-year-survival, compared with those who did not face EAD (NoEAD), 96% and 96% for EAD vs. 89% and 71% for NoEAD, respectively (p = 0.03). None of the donor/graft characteristics was associated with EAD even if the graft was moderately steatotic or fibrotic or from an aged donor. For the first time, this study shows that macrovesicular steatosis >30% might be a warning factor involved in the risk of graft loss or a cause of graft discard after the MP treatment. On the other hand, the MP seems to be useful in reducing the donor and graft weight in the development of EAD.

Design, Synthesis, and Bioevaluation of a Novel Hybrid Molecular Pyrrolobenzodiazepine-Anthracenecarboxyimide as a Payload for Antibody-Drug Conjugate

A novel series of hybrid molecules combining pyrrolobenzodiazepine (PBD) and anthracenecarboxyimide pharmacophores were designed, synthesized, and tested for in vitro cytotoxicity against various cancer cell lines. The most potent compound from this series, 37b3, exhibited a subnanomolar level of cytotoxicity with an IC₅₀ of 0.17-0.94 nM. 37b3 induced DNA damage and led to tumor cell cycle arrest and apoptosis. We employed 37b3 as a payload to conjugate with trastuzumab to obtain the antibody-drug conjugate (ADC) T-PBA. T-PBA maintained its mode of target and internalization ability of trastuzumab. We demonstrated that T-PBA could be degraded through the lysosomal pathway to release the payload 37b3 after internalization. T-PBA showed a powerful killing effect on Her2-positive cancer cells in vitro. Furthermore, T-PBA significantly inhibited tumor growth in gastric and ovarian cancer xenograft mouse models without overt toxicity. Collectively, these studies suggest that T-PBA represents a promising new ADC that deserves further investigation.

Transarterial chemoembolization of hepatocellular carcinoma before liver transplantation and risk of post-transplant vascular complications: a multicentre observational cohort and propensity score-matched analysis

BACKGROUND

Transarterial chemoembolization (TACE) in patients with hepatocellular cancer (HCC) on the waiting list for liver transplantation may be associated with an increased risk for hepatic artery complications. The present study aims to assess the risk for, primarily, intraoperative technical hepatic artery problems and, secondarily, postoperative hepatic artery complications encountered in patients who received TACE before liver transplantation.

METHODS

Available data from HCC liver transplantation recipients across six European centres from January 2007 to December 2018 were analysed in a 1 : 1 propensity score-matched cohort (TACE versus no TACE). Incidences of intraoperative hepatic artery interventions and postoperative hepatic artery complications were compared.

RESULTS

Data on postoperative hepatic artery complications were available in all 876 patients (425 patients with TACE and 451 patients without TACE). Fifty-eight (6.6 per cent) patients experienced postoperative hepatic artery complications. In total 253 patients who had undergone TACE could be matched to controls. In the matched cohort TACE was not associated with a composite of hepatic artery complications (OR 1.73, 95 per cent c.i. 0.82 to 3.63, P = 0.149). Data on intraoperative hepatic artery interventions were available in 825 patients (422 patients with TACE and 403 without TACE). Intraoperative hepatic artery interventions were necessary in 69 (8.4 per cent) patients. In the matched cohort TACE was not associated with an increased incidence of intraoperative hepatic artery interventions (OR 0.94, 95 per cent c.i. 0.49 to 1.83, P = 0.870).

CONCLUSION

In otherwise matched patients with HCC intended for liver transplantation, TACE treatment before transplantation was not associated with higher risk of technical vascular issues or hepatic artery complications.

Combination Foretinib and Anti-PD-1 Antibody Immunotherapy for Colorectal Carcinoma

Immune checkpoint inhibitors have achieved unprecedented success in cancer immunotherapy. However, the overall response rate to immune checkpoint inhibitor therapy for many cancers is only between 20 and 40%, and even less for colorectal cancer (CRC) patients. Thus, there is an urgent need to develop an efficient immunotherapeutic strategy for CRC. Here, we developed a novel CRC combination therapy consisting of a multiple receptor tyrosine kinase inhibitor (Foretinib) and anti-PD-1 antibody. The combination therapy significantly inhibited tumor growth in mice, led to improved tumor regression without relapse (83% for CT26 tumors and 50% for MC38 tumors) and prolonged overall survival. Mechanistically, Foretinib caused increased levels of PD-L1 via activating the JAK2-STAT1 pathway, which could improve the effectiveness of the immune checkpoint inhibitor. Moreover, the combination therapy remodeled the tumor microenvironment and enhanced anti-tumor immunity by further increasing the infiltration and improving the function of T cells, decreasing the percentage of tumor-associated macrophages (TAMs) and inhibiting their polarization toward the M2 phenotype. Furthermore, the combination therapy inhibited the metastasis of CT26-Luc tumors to the lung in BALB/c mouse by reducing proportions of regulatory T-cells, TAMs and M2 phenotype TAMs in their lungs. This study suggests that a novel combination therapy utilizing both Foretinib and anti-PD-1 antibody could be an effective combination strategy for CRC immunotherapy.

Serum Metabolic Profiling Analysis of Chronic Gastritis and Gastric Cancer by Untargeted Metabolomics

Purpose

Gastric cancer is a common tumor of the digestive system. Identification of potential molecules associated with gastric cancer progression and validation of potential biomarkers for gastric cancer diagnosis are very important. Thus, the aim of our study was to determine the serum metabolic characteristics of the serum of patients with chronic gastritis (CG) or gastric cancer (GC) and validate candidate biomarkers for disease diagnosis.

Experimental Design

A total of 123 human serum samples from patients with CG or GC were collected for untargeted metabolomic analysis via UHPLC-Q-TOF/MS to determine characteristics of the serum. Principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and heat map were used for multivariate analysis. In addition, commercial databases were used to identify the pathways of metabolites. Differential metabolites were identified based on a heat map with a t-test threshold (p < 0.05), fold-change threshold (FC > 1.5 or FC < 2/3) and variable importance in the projection (VIP >1). Then, differential metabolites were analyzed by receiver operating characteristic (ROC) curve to determine candidate biomarkers. All samples were analyzed for fasting lipid profiles.

Results

Analysis of serum metabolomic profiles indicated that most of the altered metabolic pathways in the three groups were associated with lipid metabolism (p < 0.05) and lipids and lipid-like molecules were the predominating metabolites within the top 100 differential metabolites (p < 0.05, FC > 1.5 or FC < 2/3, and VIP >1). Moreover, differential metabolites, including hexadecasphinganine, linoleamide, and N-Hydroxy arachidonoyl amine had high diagnostic performance according to PLS-DA. In addition, fasting lipid profile analysis showed the serum levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A1 (Apo-A1) were decreased concomitant to the progression of the progression of the disease compared with those in the control group (p < 0.05).

Conclusions

Thus, this study demonstrated that lipid metabolism may influence the development of CG to GC. Hexadecasphinganine, linoleamide, and N-Hydroxy arachidonoyl amine were selected as candidate diagnostic markers for CG and GC.

Effective antitumor activity of 5T4-specific CAR-T cells against ovarian cancer cells in vitro and xenotransplanted tumors in vivo

Ovarian cancer is considered to be the most lethal gynecologic malignancy, and despite the development of conventional therapies and new therapeutic approaches, the patient's survival time remains short because of tumor recurrence and metastasis. Therefore, effective methods to control tumor progression are urgently needed. The oncofetal tumor-associated antigen 5T4 (trophoblast glycoprotein, TPBG) represents an appealing target for adoptive T-cell immunotherapy as it is highly expressed on the surface of various tumor cells, has very limited expression in normal tissues, and spreads widely in malignant tumors throughout their development. In this study, we generated second-generation human chimeric antigen receptor (CAR) T cells with redirected specificity to 5T4 (5T4 CAR-T) and demonstrated that these CAR-T cells can elicit lytic cytotoxicity in targeted tumor cells, in addition to the secretion of cytotoxic cytokines, including IFN-γ, IL-2, and GM-CSF. Furthermore, adoptive transfer of 5T4 CAR-T cells significantly delayed tumor formation in xenografts of peritoneal and subcutaneous animal models. These results demonstrate the potential efficacy and feasibility of 5T4 CAR-T cell immunotherapy and provide a theoretical basis for the clinical study of future immunotherapies targeting 5T4 for ovarian cancer.

Opportunities and obstacles of targeted therapy and immunotherapy in small cell lung cancer

Small cell lung cancer (SCLC) is an aggressive malignant tumour which accounts for approximately 13-15% of all newly diagnosed lung cancer cases. To date, platinum-based chemotherapy are still the first-line treatments for SCLC. However, chemotherapy resistance and systemic toxicity limit the long-term clinical outcome of first-line treatment in SCLC. Recent years, targeted therapy and immunotherapy have made great breakthrough in cancer therapy, and researchers aim to exploit both as a single agent or in combination with chemotherapy to improve the survival of SCLC patients, but limited effectiveness and the adverse events remain the major obstacles in the treatment of SCLC. To overcome these challenges for SCLC therapies, prevention and early diagnosis for this refractory disease is very important. At the same time, we should reveal more information about the pathogenesis of SCLC and the mechanism of drug resistance. Finally, new treatment strategies should also be taken into considerations, such as repurposing drug, optimising of targets, combination therapy strategies or prognostic biomarkers to enhance therapeutic effects and decrease the adverse events rates in SCLC patients. This article will review the molecular biology characteristics of SCLC and discuss the opportunities and obstacles of the current therapy for SCLC patients.

Cryptophycin-55/52 based antibody-drug conjugates: Synthesis, efficacy, and mode of action studies

Cryptophycin-52 (CR52), a tubulin inhibitor, exhibits promising antitumor activity in vitro (picomolar level) and in mouse xenograft models. However, the narrow therapeutic window in clinical trials limits its further development. Antibody-drug conjugate (ADC), formed by coupling cytotoxic compound (payload) to an antibody via a linker, can deliver drug to tumor locations in a targeted manner by antibody, enhancing the therapeutic effects and reducing toxic and side effects. In this study, we aim to explore the possibility of CR52-based ADC for tumor targeted therapy. Due to the lack of a coupling site in CR52, its prodrug cryptophycin-55 (CR55) containing a free hydroxyl was synthesized and conjugated to the model antibody trastuzumab (anti-HER2 antibody drug approved by FDA for breast cancer therapy) via the linkers based on Mc-NHS and Mc-Val-Cit-PAB-PNP. The average drug-to-antibody ratios (DARs) of trastuzumab-CR55 conjugates (named T-L1-CR55, T-L2-CR55, and T-L3-CR55) were 3.50, 3.29, and 3.35, respectively. These conjugates exhibited potent cytotoxicity in HER2-positive tumor cell lines with IC₅₀ values at low nanomolar levels (0.58-1.19 nM). Further, they displayed significant antitumor activities at the doses of 10 mg/kg in established ovarian cancer (SKOV3) and gastric cancer (NCI-N87) xenograft models without overt toxicities. Finally, the drug releases were analyzed and the results indicated that T-L3-CR55 was able to effectively release CR55 and further epoxidized to CR52, which may be responsible for its best performance in antitumor activities. In conclusion, our results demonstrated that these conjugates have the potential for tumor targeted therapy, which provides insights to further research the CR55/CR52-based ADC for tumor therapy.

Comparative RNA-sequencing profiled the differential gene expression of liver in response to acetyl-CoA carboxylase inhibitor GS-0976 in a mouse model of NASH

Background

Non-alcoholic steatohepatitis (NASH) is a progressive liver disease characterized by hepatic steatosis, lobular inflammation and fibrosis. Acetyl-CoA carboxylase (ACC) isoform 1 and 2 involved in de novo lipogenesis (DNL) and fatty acid oxidation have been identified as a therapeutic target in NASH. GS-0976, the inhibitor of ACC1 and ACC2, has achieved favorable therapeutic effects in clinical trials with NASH. The purpose of this study was to explore the transcriptional alterations regulated by GS-0976 in NASH.

Methods

C57BL/6 mice were fed on a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) or normal diet for 12 weeks. Mice were treated with or without GS-0976 (3 mg/kg per day) in the last 8 weeks. Oil Red O, Haematoxylin-eosin (H & E), and Sirius Red were used to evaluate hepatic steatosis, inflammation and fibrosis. The comparative RNA-sequencing was conducted to analyse the hepatic gene expression profiles in mice. Reverse transcription–polymerase chain reaction analysis was performed to validate the differential expression of representative genes.

Results

GS-0976 attenuated the steatosis, inflammation, and fibrosis of NASH in CDAHFD mouse model. High-throughput sequencing and differential gene expression analysis showed that there were 516 up-regulated genes and 525 down-regulated genes after GS-0976 treatment. Genes involved in the metabolic process, extracellular matrix formation, immune response, and angiogenesis were significantly enriched. The “Metabolic pathways” and “ECM-receptor interaction” pathways were the most significantly enriched KEGG pathways in the up-regulated and down-regulated differentially expressed genes (DEGs), respectively.

Conclusions

Transcriptome analysis showed that GS-0976 could regulate the expression of genes related to metabolism, inflammation and fibrosis in NASH. The global transcriptomic changes in gene expression promote the further understanding for the inhibition mechanisms of GS-0976 in NASH.

Targeting of DDR1 with antibody-drug conjugates has antitumor effects in a mouse model of colon carcinoma

DDR1 has been identified as a cancer‐associated receptor tyrosine kinase that is highly expressed in several malignancies relative to normal tissues. Clinically approved multi‐kinase inhibitors, such as nilotinib, inhibit DDR1‐mediated tumor growth in xenograft models, suggesting DDR1 might be a potential target for cancer treatments. Here, we employed an antibody‐based strategy with a novel anti‐DDR1 antibody‐drug conjugate (ADC) for colon carcinoma treatment. We developed T₄H₁₁‐DM4, an ADC targeting DDR1 which carries the tubulin inhibitor payload DM4. Immunohistochemical analysis of a tissue microarray containing 100 colon cancer specimens revealed that DDR1 was highly expressed in 81% of tumor tissues. Meanwhile, high expression of DDR1 was associated with poor survival in patients. In vitro, T₄H₁₁‐DM4 exhibited potent anti‐proliferative activity with half maximal inhibitory concentration (IC₅₀) values in the nanomolar range in a panel of colon cancer cell lines. In vivo, the antitumor efficacy of T₄H₁₁‐DM4 was evaluated in three colon cancer cell lines expressing different levels of DDR1. T₄H₁₁‐DM4 achieved complete tumor regression at doses of 5 and 10 mg·kg⁻¹ in HT‐29 and HCT116 tumor models. Moreover, a correlation between in vivo efficacy of T₄H₁₁‐DM4 and the levels of DDR1 expression on the cell surface was observed. Tumor cell proliferation was caused by the induction of mitotic arrest, indicating that the antitumor effect in vivo was mediated by DM4. In addition, T₄H₁₁‐DM4 was efficacious in oxaliplatin‐resistant colon cancer models. In exploratory safety studies, T₄H₁₁‐DM4 exhibited no overt toxicities when multi‐doses were administered at 10 mg·kg⁻¹ into BALB/c nude mice or when a single dose up to 50 mg·kg⁻¹ was administered into BALB/c mice. Overall, our findings highlight the potential of DDR1‐targeted ADC and may facilitate the development of a new effective therapeutic strategy for colon cancer.

FTO rs9939609 Gene Polymorphism and Obesity: Lack of Association in Kidney Transplantation

The fat mass and obesity-associated (FTO) gene is one of the most important obesity susceptibility genes. Some FTO gene polymorphisms have been associated with obesity, diabetes, and hypertension, all conditions for which, after transplant, there is increased susceptibility, due to effects of immunosuppressive regimens. To evaluate whether FTO could be a candidate for targeted preventive intervention in the transplant setting, we investigated whether the common genetic variation, FTO rs9939609T>A, could affect weight gain and risk of cardiovascular complications in kidney transplantation.

METHODS

In 198 kidney transplant recipients, FTO rs9939609 was investigated in association with body mass index (BMI)/obesity and with other clinical markers of posttransplant risk, then monitored up to 5 years after transplantation. Genotyping was performed using an allelic discrimination method on a real-time polymerase chain (PCR) system. Associations were analyzed using the chi-square test; differences between genotypes were examined with analysis of variance or Kruskal-Wallis test; tests for repeated measures and a general linear model analysis controlling for age and gender were also utilized.

RESULTS

Allele and genotype frequencies of FTO rs9939609 in recipients (T/T, 29.8%; T/A, 49.0%; A/A, 21.2%; A, 45.7%; T, 54.3%) reflect those present in healthy Caucasian populations. In the face of pre-/posttransplant differences in total cholesterol, triglycerides, or fasting glucose, results did not show significant changes in these factors among genotypes either before or after transplantation.

CONCLUSION

This study highlights a lack of association of FTO rs9939609T>A genotypes and posttransplant weight gain, plasma lipids, and fasting blood glucose in kidney transplantation.

Expression of 5T4 extracellular domain fusion protein and preparation of anti-5T4 monoclonal antibody with high affinity and internalization efficiency

5T4, a membrane protein, is overexpressed in many tumor tissues but rarely expressed in normal tissues. Here, CHO-5T4⁺ cells were generated and served as the antigen to immunize mice. Hybridoma techniques were employed to produce monoclonal antibodies (mAbs). The recombinant protein of human IgG Fc-fused extracellular domain of 5T4 (5T4 ECD-Fc) was obtained from transient expression in HEK293F cells. The fusion protein 5T4 ECD-Fc and CHO-5T4⁺ cells were respectively utilized to screen anti-5T4 antibodies that could bind to the native antigen. In preliminary screening, three hundred and fifty mAbs were obtained. Via surface plasmon resonance and flow cytometry screening, seven anti-5T4 mAbs stood out. Among them, H6 showed a high affinity (K_D = 1.6 × 10^-11 M) and internalization percentage (36% for 1 h and 80% for 4 h). The molecular weight and isoelectric point of H6 were determined by LC-MS and iCIEF. Moreover, the specific reactivity of H6 was demonstrated by western blotting, flow cytometry, and immunohistochemistry, respectively. In conclusion, we produced human recombinant protein of 5T4 extracellular domain and developed high-affinity internalizing monoclonal antibodies which may be applied in the 5T4-targeting ADC therapy and basic research.

Surgical Technique Notes of Arterial Vascular Reconstruction During Kidney Transplantation: Personal Experience and Literature Review

BACKGROUND

Arterial vascular anomalies in patients undergoing kidney transplantation (KT) are correlated with a higher incidence of early surgical complications, potentially causing graft loss. Arterial reconstruction allows patients to overcome these surgical challenges, thus minimizing the risk of poor outcomes. The aim of the present study is to retrospectively investigate the safety and effectiveness of the multiple arterial reconstruction technique with a Teflon patch in case of an unavailable aortic patch: to do so, surgical complications, graft function, and patient survival were evaluated.

METHODS

During the period January 2009 to August 2016, 202 adult deceased-donor KTs were performed at our center. Group A (n = 27; reconstruction of multiple arteries) and Group B (n = 175; control group) were compared.

RESULTS

No differences were observed between the 2 groups in terms of early postoperative course, with no vascular complication observed in Group A. No vascular patch infections were reported, nor longer cold ischemia time rates. Similarly, long-term survival rates were similar between the 2 groups.

CONCLUSIONS

The Teflon-patch arterial reconstruction technique appears to be safe and effective, with an acceptable balance of benefits and potential risks of using a prosthetic material. Studies based on larger series are needed to further validate this approach.

A novel 5T4-targeting antibody-drug conjugate H6-DM4 exhibits potent therapeutic efficacy in gastrointestinal tumor xenograft models

5T4, also named as trophoblast glycoprotein, is often upregulated in some cancer cells. Here, we demonstrated that 5T4 was highly expressed in gastric, colorectal, and pancreatic cancer, associated with significantly poor prognosis of gastrointestinal (GI) cancer patients. To search for new targeting drugs for GI cancer, we developed a novel anti-5T4 monoclonal antibody with high affinity and robust internalization ability and conjugated it to the potent microtubule inhibitor DM4 to produce conjugate H6-DM4. This antibody-drug conjugate (ADC) displayed significant cytotoxicity in a panel of GI cancer cell lines with IC50 values in the nanomolar range. H6-DM4 eradicated established GI tumor xenograft models at 2.5 mg/kg or 10 mg/kg without observable toxicity. Further, 5T4 was highly expressed in cancer-initiating cells (CICs) compared with non-CICs in colorectal cancer. In vitro and in vivo, treatment with H6-DM4 exhibited a powerful efficacy on colorectal CICs. Additionally, colorectal cancer cells resistant to platinum were effectively eliminated by H6-DM4. Taken together, our results showed 5T4-positive GI cancer cells, colorectal cancer-initiating cells, and platinum-resistant colorectal cancer cells were potently eliminated by H6-DM4, indicating H6-DM4 may be a potential candidate drug for GI cancer treatment.

Promiximab-duocarmycin, a new CD56 antibody-drug conjugates, is highly efficacious in small cell lung cancer xenograft models

Small cell lung cancer (SCLC) is of a highly invasive and metastatic lung cancer subtype and there had not been effective targeted therapies. CD56, a cell surface marker highly expressed on most SCLC, is a promising therapeutic target for treatment of this aggressive cancer. In this study, we generated a novel anti-CD56 antibody named promiximab, characterized by high affinity, internalization and tumor specificity. Then, the promiximab was conjugated with a potent DNA alkylating agent duocarmycin via reduced interchain disulfides to yield the promiximab-Duocarmycin (promiximab-DUBA) conjugates. Mass spectrometry analysis showed promiximab-DUBA had an average DAR (Drug-to-Antibody Ratio) of about 2.04. In vitro, promiximab-DUBA exerted strong inhibitory effects on SCLC cell lines NCI-H526, NCI-H524 and NCI-H69, with IC50 values of 0.07 nmol/L, 0.18 nmol/L and 0.29 nmol/L, respectively. In vivo antitumor activity, promiximab-DUBA at the dose of 5 mg/kg and 10 mg/kg every three days with a total of three times were sufficient to induce sustained regression of NCI-H526 tumors over control treatment with promiximab. Mostly, no recurrence was observed until 65 days post treatment with promiximab-DUBA. In the NCI-H69 subcutaneous xenograft model, significant inhibition of tumor growth was also observed following administration of promiximab-DUBA at the dose of 5 mg/kg or 10 mg/kg. Moreover, body weight and histopathology of major organs (liver, spleen, heart, lung and kidney) showed no significant changes after treatment of promiximab-DUBA. In conclusion, promiximab-DUBA is highly efficacious in small cell lung cancer xenograft models, and provides a new immunotherapy approach for SCLC.

Therapeutic potential of an anti-HER2 single chain antibody-DM1 conjugates for the treatment of HER2-positive cancer

Antibody-drug conjugates (ADCs) take the advantage of monoclonal antibodies to selectively deliver highly potent cytotoxic drugs to tumor cells, which have become a powerful measure for cancer treatment in recent years. To develop a more effective therapy for human epidermal growth factor receptor 2 (HER2)-positive cancer, we explored a novel ADCs composed of anti-HER2 scFv-HSA fusion antibodies conjugates with a potent cytotoxic drug DM1. The resulting ADCs, T-SA1-DM1 and T-SA2-DM1 (drug-to-antibody ratio in the range of 3.2-3.5) displayed efficient inhibition in the growth of HER2-positive tumor cell lines and the half-maximal inhibitory concentration on SKBR-3 and SKOV3 cells were both at the nanomolar levels in vitro. In HER2-positive human ovarian cancer xenograft models, T-SA1-DM1 and T-SA2-DM1 also showed remarkable antitumor activity. Importantly, three out of six mice exhibited complete remission without regrowth in the high-dose group of T-SA1-DM1. On the basis of the analysis of luminescence imaging, anti-HER2 scFv-HSA fusion antibodies, especially T-SA1, showed strong and rapid tumor tissue penetrability and distribution compared with trastuzumab. Collectively, the novel type of ADCs is effective and selective targeting to HER2-positive cancer, and may be a promising antitumor drug candidate for further studies.

Multiple Organ Failure Associated With Coxsackie Virus in a Kidney Transplant Patient: Case Report

INTRODUCTION

Viral myocarditis can emerge with various symptoms, including fatal arrhythmia and cardiogenic shock, potentially evolving in chronic myocarditis or dilatative cardiomyopathy. We report a case of a kidney transplant patient affected by coxsackie viral myocarditis.

METHODS

A 49-year-old man was admitted to our hospital with dyspnea and fever in August 2014. He underwent living donor kidney transplantation in 1986 and polar graft resection for papillary carcinoma in 2012.

RESULTS

The initial investigation showed pulmonary congestion, pancreatitis, increased serum troponin I, and increased liver enzyme levels. Echocardiogram revealed an ejection fraction (EF) of 20% and PAPS 45 mm Hg. He underwent coronary stent implantation, started hemodialysis, and continued on low-dose steroid immunosuppressive therapy. The clinical course improved rapidly, but endomyocardial biopsy showed acute myocarditis. Further investigation revealed a high antibody titer against coxsackievirus B4 and B5. Pancreatic enzyme levels normalized 2 months after patient admission; his cardiac condition improved after 6 months. The patient has been followed for 1 year, and his left ventricular EF is stable (45%).

CONCLUSIONS

Viral myocarditis represents a serious clinical condition requiring a fast therapeutic intervention. This patient's clinical course suggests that changes in his immunosuppressive therapy were associated with progressive amelioration of his viral myocarditis.

Kidney Transplantation, Polymorphisms of IL-18, and Other Pro-Inflammatory Genes and Late Post-Transplant Outcome

BACKGROUND

Functional polymorphisms of molecules involved in immune-mediated mechanisms of allograft rejection could be predictive of increased risk for early and late post-transplant complications. In the past years, the challenge for long-term graft survival in kidney recipients is the implementation of personalized approaches. In this study, effects of interleukin (IL)-18-137G/C (rs187238), -607C/A (rs1946518), and other pro-inflammatory cytokine gene polymorphisms (tumor necrosis factor [TNF]-α-308G/A, rs1800629, IL-6-174G/C, rs1800795, and interferon [IFN]-γ+874A/T, rs2430561) on the main post-transplant risk parameters and diseases (metabolic, cardiovascular, infective, and chronic allograft rejection) were assessed in kidney-transplanted patients.

METHODS

One hundred seventy-nine transplanted patients were retrospectively analyzed for clinical and biochemical parameters and onset of post-transplant complications. Taqman allelic discrimination and PCR-SSP (polymerase chain reaction-sequence specific primers) techniques were used for genotyping.

RESULTS

No predictive effects of allele and genotypes of IL-18-607C/A, TNF-α-308G/A, IL-6-174G/C, and IFN-γ+874A/T gene polymorphisms and onset of risk factors and late complications were evidenced. However, Kaplan-Meier analysis evidenced a weak effect of IL-18-137G/C genotypes on graft survival.

CONCLUSIONS

Analyzing associations between some pro-inflammatory cytokine gene polymorphisms and onset of the most relevant risk factors and late complications of kidney transplant, results suggested a possible impact of IL-18-137G/C genotypes on graft survival, which deserves further studies.

Delayed Introduction of Everolimus in De Novo Renal Transplanted Patients: A Single-Center Experience

INTRODUCTION

Immunosuppressive protocols containing everolimus (EVR) preserve good renal function in kidney transplantation (KT), although they are often complicated by several adverse events. We have evaluated the efficacy and safety of a protocol with late (1 month after KT) EVR introduction.

MATERIAL AND METHODS

This study randomized 49 de novo patients undergoing KT between September 2012 and June 2014 into 2 groups: group A (n = 24) with late EVR introduction and tacrolimus reduction, and group B (control group; n = 25) with a standard immunosuppressive regimen. Primary aims were 1-year patient and graft survivals and acute rejection rates. Secondary aims were related to wound, metabolic, and hematologic complications.

RESULTS

Patient and graft survivals were similar in both groups. One year after KT, median serum creatinine was inferior in group A (1.4 vs 1.8 mg/dL; P = .004). Late acute rejection (8.3 vs 12.0%; P = 1.0) and wound complication (4.2 vs 4.0%; P = 1.0) rates were similar. Higher cholesterol and triglycerides and lower platelets and hemoglobin levels were observed in group A.

CONCLUSIONS

In our experience, delayed introduction of EVR shows similar results with respect to its early introduction, contemporaneously presenting fewer wound complications and lymphoceles. A higher rate of metabolic and hematologic complications are, however, observed in patients under EVR therapy. Further multicenter studies should be performed to confirm these preliminary results.

Inhibition of adipogenic differentiation of bone marrow mesenchymal stem cells by erythropoietin via activating ERK and P38 MAPK

We examined whether erythropoietin (EPO) can inhibit adipogenic differentiation of mesenchymal stem cells (MSCs) in the mouse bone marrow and its underlying mechanism. We separated and extracted mouse bone marrow MSCs and induced adipogenic differen-tiation using 3-isobutyl-1-methylxanthine, insulin, and dexamethasone. Different concentrations of EPO were added to the cells and observed by Oil Red O staining on the 20th day to quantitatively analyze the degree of cell differentiation. mRNA expression levels of peroxysome proliferator-activated receptor γ (PPARγ), CCAAT enhancer binding protein α, and adiponectin were analyzed by real-time quantitative polymerase chain reaction, and the activity of PPARγ, extracellular sig-nal-regulated kinase (ERK), and p38 mitogen-activated protein kinase (p38 MAPK) were determined by western blotting. EPO significantly inhibited adipogenic differentiation of MSCs after 20 days and reduced absorbance values by Oil Red O staining without affecting proliferation activity. EPO downregulated the mRNA expression of PPARγ, CCAAT enhancer binding protein α, fatty acid binding protein 4, and adiponec-tin during adipogenesis and increased protein phosphorylation of ERK, p38 MAPK, and PPARγ during differentiation. EPO downregulated the mRNA expression of PPARγ, CCAAT enhancer binding protein α, fatty acid binding protein 4, and adiponectin by increasing protein phosphor-ylation of ERK, p38 MAPK, and PPARγ during differentiation, which inhibited adipogenic differentiation of MSCs.

Predictive factors of recurrence of hepatocellular carcinoma after liver transplantation: a multivariate analysis

We analyzed predictive risk factors for recurrence of hepatocellular carcinoma (HCC) after orthotopic liver transplantation (OLT). We retrospectively analyzed the clinical data from 109 consecutive HCC patients who underwent OLT at our center from 1988 to 2007. We excluded all patients who died due to factors other than tumor recurrence within the first year (n = 24). The remaining 85 patients were enrolled in either a recurrence group (A; n = 19) or a nonrecurrence group (B; n = 66). Upon univariate analysis, the 2 groups were significantly different for 11 parameters. Group A included more females (P = .05), noncirrhotic liver recipients (P = .003), "up-to 7 status" patients (HCC with 7 as the sum of the size of the largest tumor [cm] and the number of tumors, P < .0001), patients exceeding Milan criteria (MC; P < .0001) or University of California San Francisco (UCSF) criteria (P < .0001), and OLT performed before 1999 (P = .003). Group A also showed a higher number of lesions (P = .035), a greater sum of diameters of the lesions (P < .0001), a major number of macrovascular (P < .0001) and microvascular invasions (P < .0001), and an increased number of G3-G4 grading (P = .006). Only microvascular invasion (P = .007) and exceeding UCSF criteria (P = .003) were independent risk factors for recurrence upon multivariate analysis. Patients with both these parameters are not candidates for OLT. Microvascular invasion is a good predictive parameter, but is impossible to detect preoperatively. New pre-OLT predictive risk factors are needed to achieve optimal results.

Use of octogenarian donors for liver transplantation: a survival analysis

Use of very old donors in liver transplantation (LT) is controversial because advanced donor age is associated with a higher risk for graft dysfunction and worse long-term results, especially for hepatitis C virus (HCV)-positive recipients. This was a retrospective, single-center review of primary, ABO-compatible LT performed between 2001 and 2010. Recipients were stratified in four groups based on donor age (<60 years; 60-69 years; 70-79 years and ≥80 years) and their outcomes were compared. A total of 842 patients were included: 348 (41.3%) with donors <60 years; 176 (20.9%) with donors 60-69 years; 233 (27.7%) with donors 70-79 years and 85 (10.1%) with donors ≥80 years. There was no difference across groups in terms of early (≤30 days) graft loss, and graft survival at 1 and 5 years was 90.5% and 78.6% for grafts <60 years; 88.6% and 81.3% for grafts 60-69 years; 87.6% and 75.1% for grafts 70-79 years and 84.7% and 77.1% for grafts ≥80 years (p = 0.065). In the group ≥80 years, the 5-year graft survival was lower for HCV-positive versus HCV-negative recipients (62.4% vs. 85.6%, p = 0.034). Based on our experience, grafts from donors ≥80 years may provide favorable results but require appropriate selection and allocation policies.

Expanded criteria for hepatocellular carcinoma after liver transplantation: a 20-year evolution

BACKGROUND/AIM

Milan Criteria (MC) consent excellent survivals for hepatocellular carcinoma (HCC) after liver transplantation (LT). However, several new expanded criteria were proposed, with the intent to increase the HCC patients eligible for LT, maintaining acceptable recurrence rates. The aim of the present study was to analyze a cohort of HCC patients, evaluating the evolutions in its management during the last 20 years and comparing the disease-free survivals among three different periods.

METHODOLOGY

HCC patients (n = 122) were transplanted and stratified in three periods: 1st (1988-1998, liberal selection), 2nd (1999-2003, use of MC) and 3rd (2004-2008, use of UCSF criteria). The three periods were analyzed and their survivals were compared.

RESULTS

Statistical differences were reported at univariate analysis regarding to both dimensional (total tumor diameter) and biological (alpha feto-protein, microvascular invasion) HCC features. Comparing the 5-year survival rates, a progressive increase was observed in the three periods (62.6%, 87.9% and 88.4%, respectively), with a significant difference between 1st and the second periods (p = 0.008).

CONCLUSIONS

In our experience, use of UCSF criteria is safe, with a contemporaneous increased number of transplants and better survivals. Introduction of new selection criteria, also based on biological features, is on the way.

Conversion from twice-daily to once-daily Tacrolimus administration in liver transplant patient: results of long term follow-up

OBJECTIVES

The aim of this study was to assess the long term effects of once-daily tacrolimus (OD-TAC) in a cohort of stable liver recipients converted from the twice daily tacrolimus (TD TAC), with a particular attention on the possible effects on renal function.

PATIENTS AND METHODS

Between September 2008 and September 2010 conversion from TD-TAC to OD-TAC was proposed in adult stable liver transplant recipients who were followed as outpatients in our Transplant centre. Conversion from TC-TAC to OD-TAC was based on a 1 mg: 1 mg proportion. Tacrolimus through levels, laboratory parameters, metabolic disorders and any adverse events were evaluated at 1, 3, 6, 12 and 24 months after conversion. Renal function was evaluated using creatinine plasma levels and estimated glomerular filtration rate (GFR) derived from the Modification of Diet in Renal Disease (MDRD). Analysis of variance and t test for paired data were utilised for the comparison of the results obtained at the scheduled controls.

RESULTS

Sixty-five patients were enrolled in the study (50 males, 15 females, mean age 59±8 years). Median time since liver transplant (LT) was 39 months (range: 6 to 83 months). All patients were followed for a minimum of 12 months. Ninety per cent of patients stabilized their blood levels within 45 days. Liver function, glucose and plasma lipids concentration and arterial blood pressure remained stable during the study. Renal function improved during the 24 months of follow-up. No adverse events or acute rejection episodes were recorded during the study.

CONCLUSIONS

Considering the advantage on patient compliance, the equivalent efficacy and the adequate safety of OD-TAC formulation may represent a useful option in liver transplant patients, with a possible advantage on renal function.

Mirizzi Syndrome in a patient with an accessory hepatic duct

Mirizzi syndrome (MS) represents an uncommon clinical condition, being characterized by a narrowing of the common hepatic duct or its erosion by stones impacted in the cystic duct or gallbladder Hartman's pouch. Very uncommonly, MS can be reported in patients with contemporaneous bile duct anomalies. The case is reported of a 76-year-old Caucasian woman with a MS with a cholecystobiliary fistula and a contemporaneous aberrant biliary duct for the right posterior segments.Due to the presence of an anatomical abnormality, an open approach was decided: also during surgery, it was impossible to clarify which part of the biliary tree the accessory duct merged into. After surgery, post-operative course was uneventful: the patient is alive without medical problems (follow-up: 16 months). MS represents a challenge for the surgeon. Contemporaneous presence of biliary abnormalities is anecdotic, increasing the risk of iatrogenic injuries. An open approach may be preferred in these conditions.

Living organ donation, a therapeutic possibility, is still poorly used in Italy: a national analysis

Validity of living donor kidney transplantation is universally accepted. In contrast, after enthusiastic adoption in the 1990s, living donor liver transplantation has decreased in recent years. The aim of the present study was to evaluate retrospectively the current use of this form of donation in Italy by comparing liver and kidney cadaveric and living donations from 2002 to 2010. The number of liver transplantations from living donors has decreased from 34 in 2002 (3.9% of total) to 13 in 2010 (1.3% of total). In contrast, kidney transplantation from living donors increased from 126 (7.9% of total) to 186 (11% of total). We observed that living donations for kidney transplantation are still underused, especially with unrelated donors. Living donor liver transplantation has decreased in recent years; this procedure should be reserved to centers with particular expertise. It would be appropriate to implement programs to increase the attention of health professionals and the general population and to integrate living donations into programs of deceased organ donation.

Model for end-stage liver disease dynamic stratification of survival benefit

Only patients with Model for End-stage Liver Disease (MELD) scores ≥18 or ≥17 experience a survival benefit (SB) at 12 and 36 months after liver transplantation (OLT). The SB calculation estimates the difference after stratification for risk categories between the survival rate of transplanted versus waiting list patients. The aim of this study was to perform a short- and long-term (60 months) SB analyses of a Italian OLT program. One-hundred seventy-one patients were stratified into four MELD classes (6-14, 15-18, 19-25, 26-40), and two groups: namely, waiting list (WL) and transplanted groups (TX). The median waiting time for transplanted patients was 4.4 months (range, 0-35). SB was expressed as mortality hazard ratio (MHR) as obtained through a Cox regression analysis using as a covariate the status of each patient in the waiting list (WL = 0, reference group) or the TX group (TX = 1). Values over 1 indicated the MHR in favor of the WL with the values below 1 indicating MHR in favor of Tx. In the MELD class 6 to 14, the MHR was above 1 at 3 and 6 months, indicating an SB in favor of WL; subsequently, the MHR dropped below 1, indicating an SB in favor of TX (P < .05). In the MELD class 15 to 18 the MHR was above 1 at 3 months, but below 1 subsequently (P < .05). For MELD classes 19 to 25 and 26 to 40, the MHR was always below 1 (P < .01). According to the SB approach, patients in the MELD class 6 to 14 could safely wait for at least 36 months; patients in the MELD class 15 to 18 should likely remain no longer than 12 months on the waiting list, and all the remaining patients with MELD > 18 should be transplanted as soon as possible. OLT should not be precluded but only postponed for MELD < 19 patients.

Hepatic resection for giant haemangioma in a patient with a contemporaneous adult polycystic liver disease

Hepatic resection for giant haemangioma in a patient with a contemporaneous adult polycystic liver disease. According to Gigot classification, and to the characteristics of haemangioma surgery in these patients can be considered safe. We report the case of a 55 year-old man affected by an adult polycystic liver disease (PCLD) and a contemporaneous symptomatic haemangioma of the III segment. At the preoperative imaging scans, APCLD was classified in a type II grading according to Gigot classification. The patient underwent surgery: a wedge resection of the III segment with the exportation of the haemangioma and a fenestration of a large cyst placed in the VIII segment were performed. Post-operative course was regular and the patient was discharged uneventfully in post-operative 9th day, with a total regress of the initial symptoms. APCLD and haemangioma are two benign conditions that do not require surgery except if they cause important symptoms, such as pain. The good clinical conditions of the patient, the moderate gravity of the APCLD and the particular exofitic localisation of the cavernous haemangioma gave us the possibility to make a safe surgery for the patient. To the best of our knowledge, this is the first case reported in literature in which a liver resection for haemangioma in patient with APCLD was performed. In conclusion, liver resection for haemangioma is not contraindicated, mainly if it is symptomatic, even in the contemporaneous presence of an APCLD.

Later diagnosed with a neuroendocrine tumor, case report of a 60-year-old

Neuroendocrine tumours of the colon and rectum are infrequent. Clinical manifestations are not different from standard adenocarcinoma. Symptoms are non specific; the most common are abdominal pain, nausea and vomiting, weight loss and gastrointestinal blood loss. We report an advanced case of transverse colon neuroendocrine carcinoma with multiple metastasis. When these tumours are diagnosed, they have distance disease related to a poor prognosis for the patient. Surgery is the treatment that can offer a greater chance of survival to these patients.

P5-21-01: A Renewable Tissue Resource of Phenotypically Stable Human Breast Cancer Xenografts for Preclinical Studies

Introduction Translational breast cancer research is hampered severely by difficulties in obtaining and studying primary human breast tissue, and by the lack of in vivo preclinical models that accurately reflect patient tumor biology. These limitations are due, in part, to the fact that traditional immunocompromised mouse models are not generally permissive for growth. We sought to circumvent some of these limitations by transplanting and growing human mammary tumors in the mammary fat pad of SCID/Beige immunocompromised mice in the absence of exogenous human fibroblasts.

Aims and Methods To establish a set of stable human breast cancer xenografts for preclinical studies. Human breast cancer biopsies were received, minced into small fragments and then transplanted directly into “cleared” fat pads of recipient SCID/Beige immunocompromised mice. Transplanted fat pads were checked weekly. After initial tumor was palpated and harvested, tumor fragments were transplanted into new SCID/Beige hosts for subsequent transplant generations. Serial immunohistochemical evaluations were performed to confirm human origin and biomarker status. Analytical flow cytometry for evaluating expression of proposed “cancer stem cell” markers, and gene and protein expression analysis were carried out on all stable lines.

Results and Conclusions Xenograft lines were established directly from breast cancer patient samples, without intervening culture in vitro, using the epithelium-free mammary fat pad as the transplantation site. Of the conditions tested, xenograft take rate was highest in the presence of a low-dose estradiol pellet without exogenous human fibroblasts. Thirty six stably transplantable xenograft lines representing 27 patients were established, using pre-treatment, mid-treatment, and/or post-treatment samples. Most patients yielding xenografts were “triple-negative” (ER-PR-HER2−) (n=21), we were able to establish lines from three ER-PR-HER2+ patients, one ER+PR+HER2−, one ER+PR-HER2−and one “triple-positive” (ER+PR+HER2+) patients. Serially passaged xenografts show phenotypic consistency with the tumor of origin at the histopathology level, and remarkable stability across multiple transplant generations at both the genomic, transcriptomic, and proteomic levels. Of 27 lines evaluated fully, thirteen xenografts showed metastasis to the mouse lung. These models thus serve as a renewable, quality-controlled tissue resource, and should prove useful for preclinical evaluation of experimental therapeutics.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-21-01.

P1-03-02: The Norton-Simon Hypothesis and Cancer Stem Cells: How Cancer Stem Cells May Explain the Effectiveness of Dose-Dense Chemotherapy

Background: Systemic therapies are effective initially in controlling and reversing tumor growth; however, residual cancers will invariably re-grow despite this initial response. We have published data from paired human breast cancer samples that standard therapy every three weeks kills dividing daughter cells but not tumor-initiating cells (TICs), so that samples obtained after therapy are enriched for CD44+/CD24−/low putative “tumor-initiating” or “cancer stem” cells, indicating that standard treatment regimens are missing the critical targets, TICs. Interestingly, we have recent data in human breast tumors that indicate that TICs may in fact be chemosensitive initially, with a decrease in TICs observed within two days of chemotherapy, but shortly thereafter, TICS are actually induced by chemotherapy.

Materials and Methods: To evaluate TICs response to chemotherapy, mice with human breast tumor xenograft lines BCM-2665a and BCM-2147 were treated with vehicle, 10-, or 33-mg/kg docetaxel, and then tumors were collected for TIC assays and molecular analysis at both 48 and 72h after treatment. Using Affymetrix gene expression microarrays and reverse phase protein array (RPPA) analysis with 119 different validated antibodies, we identified pathways involved in regulation of TICs. Results: According to flow cytometric analysis for TIC markers and mammosphere (MS) formation efficiency, BCM-2665 TICs were reduced by docetaxel treatment compared to vehicle-treated at 48h post 10 mg/kg docetaxel (4-fold decrease) and 48 and 72h post 33 mg/kg docetaxel compared to control (14- and 2-fold decrease, respectively). Although the BCM-2147 TICs did not significantly decrease at any time points or doses tested, they were clearly induced at 72h post-treatment compared to control. Additionally, BCM-2665 TICs were increased within 72h post 10 mg/kg docetaxel, indicating that these time points are ideal for defining the mechanisms responsible for induction of TICs. Ingenuity Pathway Analysis of Affymetrix microarray data for both BCM-2665 and BCM-2147 revealed induction of inflammatory pathways, suggesting leukocyte infiltration associated with induction of TICs. Furthermore, RPPA analysis confirmed gene expression changes from the microarray data, and implicated apoptosis and inflammatory pathways. Sixteen of 28 proteins significantly changed with activation of CSC are involved in development of leukocytes. Discussion: These findings are consistent with the Norton-Simon Hypothesis in that chemotherapy regimens given more frequently may in fact eliminate TICs, thereby explaining the proven increased effectiveness of dose-dense chemotherapy. Based on when TICs became chemoresistant, we are comparing dose-dense treatment (4 mg/kg docetaxel every 3 days) to a traditional single dose of 32 mg/kg, in an effort to eliminate the tumor cells that cause tumor recurrence. Furthermore, our analysis of gene expression at both the RNA and protein level implicated the immune cells as TICs inducers. Since our immunocompromised mice lack T- and B- cells but have active macrophages, macrophages are indicated as inducers of TICs. We are focusing our current efforts at identifying how immune cells activate TICs and thus enhance tumorigenesis.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-03-02.

Does caval reconstruction technique affect early graft function after liver transplantation? A preliminary analysis

BACKGROUND

In the past decades, the inferior vena cava (IVC) reconstruction technique has undergone several evolutions, such as biopump, piggyback technique (PB), and laterolateral approach (LLPB). Several advantages are reported comparing the PB technique to biopump use. However, comparison between PB and LLPB has not been as well investigated. The aim of this study was to compare the results in terms of immediate graft function and intermediate graft survival among 3 subgroups characterized by distinct caval reconstruction techniques.

METHODS

We retrospectively analyzed a cohort of 200 consecutive adult patients who underwent liver transplantation from January 2001 to December 2009. The patients were stratified according to 3 caval reconstructive techniques: biopump (n=135), PB (n=32) and LLPB (n=33).

RESULTS

The LLPB group showed the shortest cold and warm ischemia times and the best immediate postoperative graft function. Survival analysis revealed LLPB patients to present the best 1-year graft survival rates: namely, 90.9% versus 75.0% and 74.1% among the PB and biopump groups, respectively (log-rank tests: LLPB vs biopump: P=.03; LLPB vs PB: P=.05). In our experience, LLPB showed the best graft survivals with an evident reduction in both cold and warm ischemia times. However, it is hard to obtain an irrefutable conclusion owing to the retrospective nature of this study, the small sample, and the different periods in which the groups were transplanted.

CONCLUSIONS

LLPB technique was a safe procedure that minimized the sequelal of ischemia-reperfusion damage. This technique yielded results superior to venovenous bypass. No definitive conclusions can to be obtained in this study comparing classic PB or LLPB.

Tacrolimus trough levels and level-to-dose ratio in stable renal transplant patients converted to a once-daily regimen

Numerous evidence has been reported to support a safe 1:1 conversion from the twice-daily tacrolimus (Tac-T) to the once-daily tacrolimus regimen (Tac-O), but frequently there is a reduction in drug trough levels, which has been estimated by some authors to be about 20%. The relationship between Tac-O dosage and trough levels after conversion is not clear. The tacrolimus trough levels-to-dose ratio has been applied to better define the wide variability in doses and blood levels of tacrolimus. The aim of this study was to evaluate tacrolimus trough levels, tacrolimus daily dosage, and tacrolimus level-to-dose ratio during 1 year pre-postconversion follow-up in 31 stable kidney transplant patients who had received Tac-T therapy for over 6 months with stable renal function. They were converted to the same dosage of Tac-O. Patients before and after conversion were their own controls. The trough levels of tacrolimus showed a slight albeit significant reduction after conversion, remaining in the therapeutic range. Nineteen percent underwent an adjustment in total daily dosage after conversion versus 39% before conversion with no significant difference. No significant differences were detected in the total daily dose administered either by tacrolimus level-to-dose ratio before or after conversion. Kidney transplant recipients under Tac-O therapy were safely maintained using the same therapeutic monitoring as when receiving Tac-T.