Ascites Of Cancer Patients Research Articles

A Biomimetic Autophagosomes-Based Nanovaccine Boosts Anticancer Immunity.

Personalized cancer vaccines based on tumor cell lysates offer promise for cancer immunotherapy yet fail to elicit a robust therapeutic effect due to the weak immunogenicity of tumor antigens. Autophagosomes, obtained from pleural effusions and ascites of cancer patients, have been identified as abundant reservoirs of tumor neoantigens that exhibit heightened immunogenicity. However, their potential as personalized cancer vaccines have been constrained by suboptimal lymphatic-targeting performances and challenges in antigen-presenting cell endocytosis. Here,a reinforced biomimetic autophagosome-based (BAPs) nanovaccine generated by precisely amalgamating autophagosome-derived neoantigens and two types of adjuvants capable of targeting lymph nodes is developed to potently elicit antitumor immunity. The redox-responsive BAPs facilitate cytosolic vaccine opening within antigen-presenting cells, thereby exposing adjuvants and antigens to stimulate a strong immune response. BAPs evoke broad-spectrum T-cell responses, culminating in the effective eradication of 71.4% of established tumors. Notably, BAPs vaccination triggers enduring T-cell responses that confer robust protection, with 100% of mice shielded against tumor rechallenge and a significant reduction in tumor incidence by 87.5%. Furthermore, BAPs synergize with checkpoint blockade therapy to inhibit tumor growth in the poorly immunogenic breast cancer model. The biomimetic approach presents a powerful nanovaccine formula with high versatilityfor personalized cancer immunotherapy.

Accurate Capture and Identification of Exosomes: Nanoarchitecture of the MXene Heterostructure/Engineered Lipid Layer.

Recently, exosome detection has become an important breakthrough in clinical diagnosis. However, the effective capture and accurate identification of cancer exosomes in a complex biomatrix are still a tough task. Especially, the large size and non-conductivity of exosomes are not conducive to highly sensitive electrochemical or electrochemiluminescence (ECL) detection. Therefore, we have developed a Ti3C2Tx-Bi2S3-x heterostructure/engineered lipid layer-based nanoarchitecture to overcome the limitations. The engineered lipid layer not only specifically captured and efficiently fused CD63 positive exosomes but also showed excellent antifouling property in the biological matrix. Moreover, the MUC1 aptamer-modified Ti3C2Tx-Bi2S3-x heterostructure further identified and covered the gastric cancer exosomes that have been trapped in the engineered lipid layer. In the self-luminous Faraday cage-type sensing system, the Ti3C2Tx-Bi2S3-x heterostructure with sulfur vacancies extended the outer Helmholtz plane and amplified the ECL signal. Therefore, this sensor can be used to detect tumor exosomes in ascites of cancer patients without additional purification. It provides a new pathway to detect exosomes and other large-sized vesicles with high sensitivity.

Tunnelled Peritoneal Catheter for Malignant Ascites-An Open-Label, Prospective, Observational Trial.

Simple SummaryRecurrent abdominal fluid collection (ascites) is a common clinical problem in patients with advanced malignancy that causes abdominal discomfort, nausea, fatigue and dyspnoea. Repetitive large volume paracentesis is the standard procedure that relieves patients from abdominal fluid; however, the procedure is painful and needs to be repeated up to several times per week. Tunnelled peritoneal PleurX catheters are implanted in the abdominal cavity as a permanent solution to drain ascites and can be used by the patient or nursing staff at home. In this study, we prospectively investigate the feasibility and safety of tunnelled peritoneal PleurX catheters in patients with malignant ascites. Our findings show that this technique is safe and can be routinely used. Tunnelled peritoneal PleurX catheters effectively reduce ascites-associated symptoms and hospitalization rates. Therefore, this technique should be considered in patients with recurrent malignant ascites.Treatment of recurrent malignant ascites in cancer patients is a challenge. Evidence based guidelines regarding the best treatment strategy are lacking. The aim of this prospective study was to investigate the safety and efficacy of a tunnelled peritoneal catheter (PleurX) in cancer patients with symptomatic ascites. Patients with symptomatic, diuretics-refractory ascites and indication for the implantation of a tunnelled peritoneal PleurX catheter were prospectively enrolled between August 2018 and July 2020. The number of catheter days, complications, amount of drained ascites and ascites-associated symptoms and hospitalization rate pre- and post-PleurX insertion were analysed. 51 Patients (64.7% male) were prospectively enrolled. The mean age was 66.6 (±7.9) years. The most common cause of ascites was pancreatic adenocarcinoma (n = 10) followed by cholangiocellular carcinoma (n = 9) and hepatocellular carcinoma (n = 8). The technical success rate of PleurX implantation was 100%. The mean volume of weakly drained ascites was 5.44l (±4.08). Major complications included cellulitis (n = 2), peritonitis and drainage dislocation (each n = 1). The mean catheter days per patient was 59.8 (±107.4) (Min 4, Max 668). Abdominal discomfort, impaired mobility, dyspnoea, fatigue, nausea and vomiting were significantly reduced 30 days after PleurX insertion (p < 0.05). Moreover, hospitalization rate was significantly reduced (p < 0.001; 27.08% of days preimplantation vs. 11.27% postimplantation). We conclude that implantation of a tunnelled ascites catheter is a safe and effective method for the treatment of refractory ascites in cancer patients with advanced disease. Serious complications are rare. Burdensome ascites-associated symptoms and hospitalization rates can be significantly reduced over a longer period of time.

Metformin promotes anticancer activity of NK cells in a p38 MAPK dependent manner

ABSTRACT Metformin, a drug prescribed to treat type 2 diabetes, has been reported to possess antitumor activity via immunity activation. However, the influence of metformin on natural killer (NK) cells is not fully understood. Here, we investigated whether metformin exerts a potent anticancer effect by activating NK cells. The results showed that sustained exposure to metformin enhances the cytolytic activity of NK-92 cells. Moreover, this enhancement of cytotoxicity by metformin was also observed in NK cells from healthy peripheral blood and cancer patient ascites. Mechanistically, metformin induced activation of the JAK1/2/3/STAT5 and AKT/mTOR pathways in a p38 MAPK-dependent manner rather than an AMPK-dependent manner. In vivo experiments, metformin also improved cancer surveillance of NK cells in mouse models of lymphoma clearance and metastatic melanoma. Additionally, combination treatment with metformin and anti-PD-1 antibodies increased the therapy response rates of B16F10 melanoma. Moreover, metformin treatment increased NK cell and T cell infiltration in tumors. Therefore, these results provide a deeper understanding of metformin on the effector function of NK cells and will contribute to the development and applications of metformin in cancer treatment strategies.

Tumor-released autophagosomes induces CD4+ T cell-mediated immunosuppression via a TLR2\u2013IL-6 cascade

BackgroundCD4+ T cells are critical effectors of anti-tumor immunity, but how tumor cells influence CD4+ T cell effector function is not fully understood. Tumor cell-released autophagosomes (TRAPs) are being recognized as critical modulators of host anti-tumor immunity during tumor progression. Here, we explored the mechanistic aspects of TRAPs in the modulation of CD4+ T cells in the tumor microenvironment.MethodsTRAPs isolated from tumor cell lines and pleural effusions or ascites of cancer patients were incubated with CD4+ T cells to examine the function and mechanism of TRAPs in CD4+ T cell differentiation and function. TRAPs-elicited CD4+ T cells were tested for their suppression of effector T cell function, induction of regulatory B cells, and promotion of tumorigenesis and metastasis in a mouse model.ResultsHeat shock protein 90α (HSP90α) on the surface of TRAPs from malignant effusions of cancer patients and tumor cell lines stimulated CD4+ T cell production of IL-6 via a TLR2–MyD88–NF-κB signal cascade. TRAPs-induced autocrine IL-6 further promoted CD4+ T cells secretion of IL-10 and IL-21 via STAT3. Notably, TRAPs-elicited CD4+ T cells inhibited CD4+ and CD8+ effector T cell function in an IL-6- and IL-10-dependent manner and induced IL-10-producing regulatory B cells (Bregs) via IL-6, IL-10 and IL-21, thereby promoting tumor growth and metastasis. Consistently, inhibition of tumor autophagosome formation or IL-6 secretion by CD4+ T cells markedly retarded tumor growth. Furthermore, B cell or CD4+ T cell depletion impeded tumor growth by increasing effector T cell function.ConclusionsHSP90α on the surface of TRAPs programs the immunosuppressive functions of CD4+ T cells to promote tumor growth and metastasis. TRAPs or their membrane-bound HSP90α represent important therapeutic targets to reverse cancer-associated immunosuppression and improve immunotherapy.

Quality of life improves after palliative placement of percutaneous tunneled drainage catheter for refractory ascites in prospective study of patients with end-stage cancer.

Percutaneous tunneled drainage catheter (PTDC) placement is a palliative alternative to serial paracenteses in patients with end-stage cancer and refractory ascites. The impact of PTDC on quality of life (QoL) and long-term outcomes has not been prospectively described. The objective was to evaluate changes in QoL after PTDC. Eligible adult patients with end-stage cancer undergoing PTDC placement for refractory ascites completed the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire and McGill Quality of Life instruments before PTDC placement and at 2 to 7 days and 2 to 4 weeks after PTDC. Catheter function, complications, and laboratory values were assessed. Analysis of QoL data was evaluated with a stratified Wilcoxon signed-rank test. Fifty patients enrolled. Survey completion ranged from 65% to 100% (median 88%) across timepoints. All patients had a Tenckhoff catheter, with 98% technical success. Median survival after PTDC was 38 days (95% confidence interval = 32, 57 days). European Organization for Research and Treatment of Cancer scores showed improvement in global QoL (p = 0.03) at 1 week postprocedure (PP). Significant symptom improvement was reported for fatigue, nausea/vomiting, pain, dyspnea, insomnia, and appetite at 1 week PP and was sustained at 3 weeks PP for dyspnea (p < 0.01), insomnia (p < 0.01), and appetite loss (p = 0.03). McGill Quality of Life demonstrated overall QoL improvement at 1 (p = 0.03) and 3 weeks (p = 0.04) PP. Decline in sodium and albumin values pre- and post-PTDC slowed significantly (albumin slope -0.43 to -0.26, p = 0.055; sodium slope -2.50 to 1.31, p = 0.04). Creatinine values increased at an accelerated pace post-PTDC (0.040 to 0.21, p < 0.01). Thirty-eight catheter-related complications occurred in 24 of 45 patients (53%). QoL and symptoms improved after PTDC placement for refractory ascites in patients with end-stage malignancy. Decline in sodium and albumin values slowed postplacement. This study supports the use of a PTDC for palliation of refractory ascites in cancer patients.

Nuclear receptor ligands induce TREM-1 expression on dendritic cells: analysis of their role in tumors

ABSTRACTDendritic cells (DCs) initiate adaptive immune responses after their migration to secondary lymphoid organs. The LXR ligands/oxysterols and the RXR ligand 9-cis Retinoic Acid (9-cis RA) were shown to dampen DC migration to lymphoid organs through the inhibition of CCR7 expression. We performed transcriptomics of DCs undergoing maturation in the presence of the LXR ligand 22R-Hydroxycholesterol (22R-HC). The analysis highlighted more than 1500 genes modulated by 22R-HC treatment, including the triggering receptor expressed on myeloid cells (TREM)-1, which was found markedly up-regulated. We tested the effect of other nuclear receptor ligands (NRL) and we reported the induction of TREM-1 following RXR, RAR and VDR activation. From a functional point of view, triggering of TREM-1 induced by retinoids increased TNFα and IL-1β release, suggesting an active role of NRL-activated TREM-1+ DCs in inflammation-driven diseases, including cancer. Consistently with this hypothesis we detected DCs expressing TREM-1 in pleural effusions and ascites of cancer patients, an observation validated by the induction of TREM-1, LXR and RAR target genes when monocyte-DCs were activated in the presence of tumor-conditioned fluids. Finally, we observed a better control of LLC tumor growth in Trem-1−/- bone marrow chimera mice as compared to wild type chimera mice. Future studies will be necessary to shed light on the mechanism of TREM-1 induction by distinct NRL, and to characterize the role of TREM-1+ DCs in tumor growth.

Tumor cell-released autophagosomes (TRAPs) promote immunosuppression through induction of M2-like macrophages with increased expression of PD-L1

BackgroundTumor-associated macrophages (TAMs) facilitate tumor progression via establishment of an immunosuppressive tumor microenvironment (TME). However, it is poorly understood how tumor cells could functionally modulate TAMs. Our previous work indicated that tumor cell-released autophagosomes (TRAPs), a type of LC3-II+ double-membrane extracellular vesicles (EVs) was sufficient to suppress anti-tumor immune responses by inducing IL-10-producing B cells and immune suppressive neutrophils. Here, we hypothesized that TRAPs may participate in regulating macrophage polarization.MethodsTRAPs isolated from multiple murine tumor cell lines and pleural effusions or ascites of cancer patients were incubated with bone marrow-derived macrophages (BMDMs) and monocytes, respectively. Cellular phenotypes were examined by flow cytometry, ELISA and quantitative PCR. TRAPs treated BMDMs were tested for the ability to suppress T-cell proliferation in vitro, and for promotion of tumor growth in vivo. Transwell chamber and neutralization antibodies were added to ascertain the inhibitory molecules expressed on BMDMs exposed to TRAPs. Knockout mice were used to identify the receptors responsible for TRAPs-induced BMDMs polarization and the signaling mechanism was examined by western blot. Autophagy-deficient tumors were profiled for phenotypic changes of TAMs and IFN-γ secretion of T cells by flow cytometry. The phenotype of monocytes from pleural effusions or ascites of cancer patients was assessed by flow cytometry.ResultsTRAPs converted macrophages into an immunosuppressive M2-like phenotype characterized by the expression of PD-L1 and IL-10. These macrophages inhibited the proliferation of both CD4+ and CD8+ T cells in vitro, and promoted tumor growth mainly through PD-L1 in vivo. TRAPs-induced macrophage polarization was dependent on TLR4-mediated MyD88-p38-STAT3 signaling. In vivo studies indicated that disruption of autophagosome formation in B16F10 cells by silencing the autophagy gene Beclin1 resulted in a remarkable delay in tumor growth, which was associated with reduced autophagosome secretion, TAMs reprogramming and enhanced T cell activation. Moreover, the levels of LC3B+ EVs appeared to correlate significantly with up-regulation of PD-L1 and IL-10 in matched monocytes from effusions or ascites of cancer patients, and TRAPs isolated from these samples could also polarize monocytes to an M2-like phenotype with increased expression of PD-L1, CD163 and IL-10, decreased expression of HLA-DR, and T cell-suppressive function.ConclusionsThese findings suggest the TRAPs-PD-L1 axis as a major driver of immunosuppression in the TME by eliciting macrophage polarization towards an M2-like phenotype, and highlight the potential novel therapeutic approach of simultaneously targeting autophagy and PD-L1.

Tumor cell-released autophagosomes (TRAP) enhance apoptosis and immunosuppressive functions of neutrophils

ABSTRACT Our previous studies have confirmed that tumor cell-released autophagosomes (TRAP) could induce the differentiation of B cells into IL-10+ regulatory B cells (Bregs) with suppressive activities on T lymphocytes. However, the mechanism of TRAP-mediated immune suppression is still largely unclear. Herein, we sought to assess the immunomodulatory effect of TRAPs on human neutrophils, a major immune cell type that infiltrates human tumor tissues. We found that TRAPs enriched from malignant effusions or ascites of cancer patients and tumor cell lines were rapidly and effectively phagocytized by neutrophils through macropinocytosis and promoted neutrophil apoptosis via reactive oxygen species (ROS) generation and caspase-3 activation. Moreover, the apoptotic neutrophils that have phagocytized TRAPs inhibited the proliferation and activation of CD4+ T and CD8+ T cells in a cell contact- and ROS-dependent manner. These findings define a novel TRAP-mediated mechanism in neutrophils that potentially suppresses the anti-tumor T cell immunity and highlight TRAPs as an important target for future tumor immunotherapy.

Protein Concentration of Refractory Ascites in Cancer Patients is Reflected by the Presence and Severity of Peritoneal and Liver Metastasis.

Ascites total protein concentration (A-TP) affects the performance of cell-free and concentrated ascites reinfusion therapy (CART). As the factors determining A-TP remain unclear, we examined peritoneal and liver metastasis. Among 98 patients who received CART, 68 with cancer, ascites from no other apparent cause, and complete CT and A-TP data were recruited. Sixty-six patients (97%) with peritoneal and/or liver metastasis on CT were divided into the peritoneal metastasis group (PM group), peritoneal and liver metastasis group (PM+LM group), and liver metastasis group (LM group). A-TP was highest in the PM group (3.9g/dL [3.4-4.4]), lowest in the LM group (1.0g/dL [0.9-2.0]), and broadly dispersed in the PM+LM group (3.3g/dL [2.0-3.8]). All differences were statistically significant. The percentage of metastasis volume occupying the liver was negatively and significantly related to A-TP in the PM+LM group. Taken together, the presence and severity of peritoneal and liver metastasis may influence A-TP.

Abstract TMEM-042: MALIGNANT EXTRACELLULAR VESICLES CAUSE MESOTHELIAL CELL DAMAGE TOWARD PERITONEAL DISSEMINATION IN OVARIAN CANCER

Abstract PURPOSE: To elucidate novel mechanisms of peritoneal dissemination by focusing on extracellular vesicles BACKGROUNDS AND SUMMARY: Metastasis to the abdominal cavity is frequently observed in ovarian cancer patients and is one of the reasons for the unfavorable outcomes. Extracellular vesicles (EVs), including exosomes and microvesicles, are small membrane vesicles that contain various bioactive molecules, such as microRNAs, mRNAs and proteins, and they are released from all cell types and play key physiological roles in intercellular communication. Recent evidence has demonstrated that cancer cells secrete EVs to both proximal surrounding cells and distal sites, thereby enabling the development of a cancer microenvironment that in turn promotes cancer metastasis. We established orthotopic mouse models by using 4 ovarian carcinoma cell lines with different metastatic traits and investigated the functions of cancer-derived EVs. The EVs from highly metastatic cells strongly induced metastatic behavior in moderately metastatic tumors. Notably, the metastatic cancer EVs efficiently induced apoptotic cell death in mesothelial cells in vitro and in vivo, thus resulting in the destruction of the peritoneal mesothelium barrier. Whole transcriptome analysis showed that MMP1 was significantly elevated in mesothelial cells treated with highly metastatic cancer EVs, and intact MMP1 mRNAs were selectively packaged in the EVs. Importantly, MMP1 expression in ovarian cancer is tightly correlated with a poor prognosis, particularly in stage I patients. Moreover, we found MMP1 mRNA-carrying EVs in the ascites of cancer patients, and these EVs also induced apoptosis in mesothelial cells. CONCLUSIONS: Our findings provide a promise for the understanding of a previously unknown mechanism for peritoneal dissemination that is associated with cancer-derived EVs, and which may be novel biomarkers for prognosis and can provide a new therapeutic strategy for inhibiting metastasis by disrupting the EVs. Citation Format: Akira Yokoi and Takahiro Ochiya. MALIGNANT EXTRACELLULAR VESICLES CAUSE MESOTHELIAL CELL DAMAGE TOWARD PERITONEAL DISSEMINATION IN OVARIAN CANCER [abstract]. In: Proceedings of the 11th Biennial Ovarian Cancer Research Symposium; Sep 12-13, 2016; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(11 Suppl):Abstract nr TMEM-042.

Malignant extracellular vesicles carrying MMP1 mRNA facilitate peritoneal dissemination in ovarian cancer

Advanced ovarian cancers are highly metastatic due to frequent peritoneal dissemination, resulting in dismal prognosis. Here we report the functions of cancer-derived extracellular vesicles (EVs), which are emerging as important mediators of tumour metastasis. The EVs from highly metastatic cells strongly induce metastatic behaviour in moderately metastatic tumours. Notably, the cancer EVs efficiently induce apoptotic cell death in human mesothelial cells in vitro and in vivo, thus resulting in the destruction of the peritoneal mesothelium barrier. Whole transcriptome analysis shows that MMP1 is significantly elevated in mesothelial cells treated with highly metastatic cancer EVs and intact MMP1 mRNAs are selectively packaged in the EVs. Importantly, MMP1 expression in ovarian cancer is tightly correlated with a poor prognosis. Moreover, MMP1 mRNA-carrying EVs exist in the ascites of cancer patients and these EVs also induce apoptosis in mesothelial cells. Our findings elucidate a previously unknown mechanism of peritoneal dissemination via EVs.

Therapeutic Application of Percutaneous Peritoneovenous (Denver) Shunt in Treating Chylous Ascites in Cancer Patients

PurposeTo evaluate the safety and efficacy of percutaneous peritoneovenous shunt (PPVS) placement in treating intractable chylous ascites (CA) in patients with cancer. Materials and MethodsData from 28 patients with refractory CA treated with PPVS from April 2001 to June 2015 were reviewed. Demographic characteristics, technical success, efficacy, laboratory values, and complications were recorded. Univariate and multivariate logistic regression analysis was performed. ResultsTechnical success was 100%, and ascites resolved or symptoms were relieved in 92.3% (26 of 28) of patients. In 13 (46%) patients with urologic malignancies, whose ascites had resulted from retroperitoneal lymph node dissection, the ascites resolved, resulting in shunt removal within 128 days ± 84. The shunt provided palliation of symptoms in 13 of the remaining 15 patients (87%) for a mean duration of 198 days ± 214. Serum albumin levels increased significantly (21.4%) after PPVS placement from a mean of 2.98 g/dL ± 0.64 before the procedure to 3.62 g/dL ± 0.83 (P < .001). The complication rate was 37%, including shunt malfunction/occlusion (22%), venous thrombosis (7%), and subclinical disseminated intravascular coagulopathy (DIC) (7%). Smaller venous limb size (11.5 F) and the presence of peritoneal tumor were associated with a higher rate of shunt malfunction (P < .05). No patient developed overt DIC. ConclusionsPPVS can safely and effectively treat CA in patients with cancer, resulting in significant improvement in serum albumin in addition to palliation of symptoms.

Diagnostic and prognostic value of SHOX2 and SEPT9 DNA methylation and cytology in benign, paramalignant, and malignant ascites.

BackgroundCytology remains the gold standard for the detection of malignant cells in ascites. However, its sensitivity is limited. The aim of this study was to evaluate DNA methylation biomarkers for the differential diagnosis of benign (ascites in patients without malignancy), malignant (ascites in cancer patients directly caused by malignancy), and paramalignant (ascites in cancer patients caused by comorbidities but not by malignancy) ascites.MethodsA cohort of 283 patients (134 cancer patients, 149 patients with benign diseases) presenting with ascites was prospectively enrolled. Ascites was evaluated by means of cytopathological investigation and DNA methylation of SHOX2 and SEPT9 in the cell-free and cellular fraction. DNA methylation in bisulfite-converted DNA was determined using quantitative methylation specific real-time PCR. Cytopathological and DNA methylation results were evaluated with regard to diagnosis and overall survival (OS).ResultsPatients with positive DNA methylation had a poor overall survival compared to methylation-negative patients (hazard ratio: HR = 1.97, p = 0.001). In multivariate survival analysis, DNA methylation was an independent prognostic parameter (p = 0.003) together with age (HR = 1.03, p < 0.001) and the presence of malignant disease (HR = 1.87, p < 0.001).The combination of methylation with cytopathological analyses led to a 42 % increase in the detection rate of malignant ascites, resulting in 37 % positively diagnosed cancer patients and a specificity of 97 %. Among cancer patients, patients with DNA methylation-positive ascites showed an adverse clinical course (HR = 1.63, p = 0.039).ConclusionsDNA methylation testing adds diagnostic and prognostic information and might constitute an effective ancillary method for the differential diagnosis of malignant, paramalignant, and benign ascites.Electronic supplementary materialThe online version of this article (doi:10.1186/s13148-016-0192-7) contains supplementary material, which is available to authorized users.

Elevated alpha1-acid glycoprotein in gastric cancer patients inhibits the anticancer effects of paclitaxel, effects restored by co-administration of erythromycin.

Paclitaxel (PTX) which easily elutes into ascites is widely used to treat gastric cancer patients with peritoneal carcinomatosis (PC), but clinical outcomes are suboptimal. Increased concentrations of α1-acid glycoprotein (AGP), an important drug-binding protein, have been reported in the plasma and ascites of cancer patients. This study sought to clarify whether AGP binds to PTX and alters its anticancer effects. AGP concentrations were measured in the serum and ascites of gastric cancer patients with PC and in the serum of healthy volunteers. The in vitro effects of AGP and AGP plus erythromycin (EM) on PTX were evaluated by MTT assays in the gastric cancer cell lines. We also measured AGP concentrations in the ascites of PC model mice and examined the effects of EM plus PTX on PC. The mean AGP concentrations in the serum and ascites of gastric cancer patients with PC were 1524 and 834 μg/mL, respectively, higher than the mean AGP concentration of 650 μg/mL observed in the sera of healthy volunteers. AGP > 400 μg/mL significantly suppressed the cell growth inhibitory effect of PTX in vitro, but the co-administration of EM restored it. Elevated AGP concentrations were observed in the ascites of PC model mice. Administration of PTX alone did not markedly diminish PC, whereas co-administration of PTX and EM significantly reduced PC (p = 0.011). AGP is an important regulatory factor modulating the anticancer activity of intraperitoneal PTX. The co-administration of PTX and EM may be effective in treating gastric cancer patients with PC.

Brief Report: Human Mesenchymal Stem-Like Cells Facilitate Floating Tumorigenic Cell Growth via Glutamine-Ammonium Cycle.

How mesenchymal stem cells (MSCs) promote tumor growth remains incompletely understood. Here, we show that mesenchymal stem-like cells (MSLCs) are commonly present in malignant pleural effusion or ascites of cancer patients, where they directly interact with tumor cells. Chemokines and chemokine receptors, especially the CCL2/CCR2 pathway, are involved in this interaction. As a result, MSLCs exert tumor-promoting effects by enhancing the proliferation and colony formation of tumor-repopulating cells. The underlying molecular basis involves MSLC release of glutamine to tumorigenic cells. Inhibition of glutamine uptake impedes MSC-mediated tumor-promoting effects. More intriguingly, MSLCs take up tumor cell-released ammonium that, in turn, favors MSLC growth. Thus, glutamine and ammonium form a vicious cycle between MSLCs and tumorigenic cells. These findings suggest a potential clinical application by targeting MSLCs in patients with malignant pleural effusions or ascites.

Immunological changes in the ascites of cancer patients after intraperitoneal administration of the bispecific antibody catumaxomab (anti-EpCAM × anti-CD3)

ObjectiveTo explore the effects of intraperitoneal (i.p.) infusion of catumaxomab, a bispecific monoclonal antibody (anti-EpCAM×anti-CD3), on T cells, NK cells and macrophages in ascites of cancer patients and to understand how ascitic immune cells can be activated despite the pervasive immunosuppressive ability of ascites microenvironment. MethodsSix patients with malignant ascites received i.p. catumaxomab infusion. Ascitic immune cells were profiled by flow cytometry and gene expression at baseline and after i.p. catumaxomab infusion. In vitro experiments enabled investigations on the adverse effect of ascites microenvironment on catumaxomab-stimulated immune cells. ResultsI.p. catumaxomab infusion enhanced the expression of the CD69 and CD38 activation molecules in CD4+ and CD8+ T cells, NK cells and macrophages, and favoured CD8+ T cell accumulation into the peritoneal cavity. An analogous immune cell activation as well as IFN-γ and IL-2 production were induced by catumaxomab in vitro. In vitro experiments showed that the immunosuppressive milieu of ascites abrogated all the immunostimulatory activities of catumaxomab. Adding EpCAM+ tumour cells to the culture permitted both catumaxomab Fab regions to engage cognate antigens and restored immunostimulatory catumaxomab activity. ConclusionsThis is the first demonstration in a clinical setting that i.p. catumaxomab infusion activates NK cells and macrophages in addition to T cells in ascites and favours CD8+ T cell accumulation into the peritoneal cavity. Moreover, our findings indicate that the concomitant binding of both catumaxomab Fab regions delivers an activation signal that is strong enough to activate immune cells despite the prevailing immunosuppressive environment of malignant ascites.

Systemic effect of catumaxomab in a patient with metastasized colorectal cancer: a case report

BackgroundCatumaxomab, the first anti-EpCAM antibody, was approved in 2009 for the treatment of malignant ascites in cancer patients with EpCAM positive tumors. We consider this case of interest as treatment with catumaxomab not only prolonged the puncture-free interval but also showed a systemic effect in a patient with metastasized colorectal cancer by regression of a pulmonary metastasis.Case presentationWe describe the case of a 78 year old patient initially diagnosed with locally advanced colon cancer and one synchronous liver metastasis in September 2010 who was treated by hemicolectomy and simultaneous atypical liver resection. During adjuvant chemotherapy the patient developed a peritoneal carcinomatosis with ascites in March 2011. Palliative chemotherapy was not well tolerated and therefore refused by the patient. Because of disease progression in June 2011 with one pulmonary metastasis and clinically predominant ascites an immunotherapy with intraperitoneal catumaxomab was started in December 2011. After treatment with catumaxomab a puncture free survival of 12 months as well as a regression of the pulmonary lesion was achieved until January 2013.ConclusionThis case suggests that treatment with catumaxomab does not only improve quality of life by local suppression of malignant ascites but also might have a systemic antitumor effect.

Detection of MicroRNA as Novel Biomarkers of Epithelial Ovarian Cancer From the Serum of Ovarian Cancer Patient

MicroRNA (miRNA) is an abundant class of small noncoding RNAs that act as gene regulators. Recent studies have suggested that miRNA deregulation is associated with the initiation and progression of human cancer. However, information about cancer-related miRNA is mostly limited to tissue miRNA. The aim of this study was to find specific profiles of serum-derived miRNAs of ovarian cancer based on a comparative study using a miRNA microarray of serum, tissue, and ascites. From 2 ovarian cancer patients and a healthy control, total RNA was isolated from their serum, tissue, and ascites, respectively, and analyzed by a microarray. Under the comparative study of each miRNA microarray, we sorted out several miRNAs showing a consistent regulation tendency throughout all 3 specimens and the greatest range of alteration in serum as potential biomarkers. The availability of biomarkers was confirmed by qRT-PCR of 18 patients and 12 controls. Out of 2222 kinds of total miRNAs that were identified in the microarray analysis, 95 miRNAs were down-regulated and 88 miRNAs were up-regulated, in the serum, tissue, and ascites of cancer patients. Among the miRNAs that showed a consistent regulation tendency through all specimens and showed more than a 2-fold difference in serum, 5 miRNAs (miR-132, miR-26a, let-7b, miR-145, and miR-143) were determined as the 5 most markedly down-regulated miRNAs in the serum from ovarian cancer patients with respect to those of controls. Four miRNAs (miR-132, miR-26a, let-7b, and miR-145) out of 5 selected miRNAs were significantly underexpressed in the serum of ovarian cancer patients in qRT-PCR. Serum miR-132, miR-26a, let-7b, and miR-145 could be considered as potential candidates as novel biomarkers in serous ovarian cancer. Also, serum miRNAs is a promising and useful tool for discriminating between controls and patients with serous ovarian cancer.

Oxidative dna Damage of Lymphocytes in Peripheral Blood and Ascites in Cancer Patients

Patients with malignant ascites (ma) usually experience poor quality of life, and treatment of this symptom remains a challenge. Oxidative stress, which can cause oxidative damage to dna, plays a pivotal role in carcinogenesis; however, the relationship between oxidative stress and dna damage to tumour-associated lymphocytes (tals) in ma is unclear. We measured the total antioxidant capacity (tac) of plasma and ma supernatant in 31 cancer patients with ma, and we used a comet assay to assess dna damage to both peripheral blood mononuclear cells (pbmcs) and tals. Measurements in age- and sex-matched healthy volunteers were used as controls. The tac of plasma was remarkably lower in cancer patients (9.73 ± 1.96 U/mL) than in healthy control subjects (11.31 ± 1.50 U/mL, p < 0.001). The tac of ma supernatant (6.34 ± 1.57 U/mL) was significantly lower than that of plasma in cancer patients (7.42 ± 1.36 U/mL, p < 0.001). The comet percentage of pbmcs was higher in cancer patients (17.26% ± 6.04%) than in healthy control subjects (9.44% ± 4.47%, p < 0.01). In cancer patients, the comet percentage of tals (36.14% ± 17.85%) was significantly higher than that of pbmcs (17.26% ± 6.04%, p < 0.001). In cancer patients with ma, negative correlations were observed between plasma tac and dna damage to pbmcs (r = -0.505, p = 0.004) and between the tac of ma supernatant and the comet percentage of tals (r = -0.588, p = 0.001). Results indicate the presence of significant oxidative damage to the dna of lymphocytes in peripheral blood and ascites from patients with ma, being especially higher in the cells from ascites. The lower tac of ma supernatant may be related to a higher degree of dna damage to tals. The present study suggests that an oxidant-antioxidant imbalance may be one of the mechanisms leading to the dna damage detected in peripheral blood and local tals in patients with ma, which may provide a novel approach to the treatment of ma.