Tumor-bearing State Research Articles

The effects of chemotherapy on resting energy expenditure, body composition, and cancer-related fatigue in women with breast cancer: a prospective cohort study

BackgroundBreast cancer (BC) is the most prevalent tumor in women. Improvements in treatment led to declined mortality, resulting in more survivors living with cancer- or therapy-induced comorbidities. In this study, we investigated the impact of neoplasia and chemotherapy on resting energy expenditure (REE) and body composition, in relation to cancer-related fatigue. Inflammatory parameters were checked as possible explanation for changes in REE.MethodsFifty-six women participated: 20 women with BC and 36 healthy controls. Patients were assessed at baseline (T0) and follow-up (T1) after 12 weeks of chemotherapy. Controls were measured once. REE was assessed with indirect calorimetry: body composition (body weight, fat mass, fat-free mass) by air plethysmography. The multidimensional fatigue index (MFI-20) was used to analyze fatigue. Baseline measurements of patients were compared to results of the healthy controls with the independent-samples T-test. The paired-samples T-test investigated the effects of chemotherapy from T0 to T1. A Pearson correlation analysis was conducted between REE, body composition, and fatigue and between REE, body composition, and inflammatory parameters. A linear regression analysis was fitted to estimate the contribution of the significantly correlated parameters. The measured REE at T0 and T1 was compared to the predicted REE to analyze the clinical use of the latter.ResultsAt baseline, patients with BC had significantly higher REE in the absence of differences in body composition. From baseline to T1, REE and body weight did not change. In contrast, fat-free mass declined significantly with concordant increase in fat mass. Fatigue deteriorated significantly. C-reactive protein at baseline predicted the change in energy expenditure. Predicted REE significantly underestimated measured REE.ConclusionsWomen with BC have higher REE in the tumor-bearing state compared to healthy controls. Chemotherapy does not affect REE but alters body composition. Predictive equations are invalid in the BC population. Results of our study can be used to implement personalized nutritional interventions to support energy expenditure and body composition and minimize long-term comorbidities.

Cancer-associated fibroblasts promote venous thrombosis through podoplanin/CLEC-2 interaction in podoplanin-negative lung cancer mouse model

BackgroundCancer-associated thrombosis (CAT) is the leading cause of morbidity and mortality. Cancer-associated fibroblasts (CAFs) are a prominent component of the tumor microenvironment that contributes to cancer progression through direct cell–cell interactions and the release of extracellular vesicles (EVs). However, the role of CAFs in CAT remains unclear. ObjectiveThis study aims to investigate whether CAFs aggravate CAT and the underlying molecular mechanism using a preclinical mouse lung cancer model. MethodsWe designed a Lewis lung carcinoma (LLC) tumor-bearing mouse model. CAFs were characterized using fluorescence immunohistostaining. The presence of podoplanin, a platelet-activating membrane protein through C-type lectin-like receptor 2 (CLEC-2), in EVs isolated from primary CAFs or LLC tumor tissues was assessed by immunoblotting. The platelet activation and aggregation abilities of the EVs were quantified using flow cytometry. Podoplanin plasma levels were measured by enzyme-linked immunosorbent assay. Venous thrombosis was induced in the femoral vein using 2.5% ferric chloride. The anti-CLEC-2 monoclonal antibody 2A2B10 was used to deplete CLEC-2 on the surface of the platelets. ResultsCAFs expressing CD90, PDGFRβ, HSP47, CD34, and vimentin, co-expressed podoplanin and induced platelet activation and aggregation in a CLEC-2-dependent manner. Tumor-bearing mice showed elevated podoplanin plasma levels. CAF-EV injection and tumor-bearing mice showed shorter occlusion time in the venous thrombosis model. Although tumor growth was not altered, antibody-induced CLEC-2 depletion suppressed venous thrombosis in the tumor-bearing state but not in the healthy condition. ConclusionCAFs and CAF-derived EVs induce CLEC-2-dependent platelet aggregation and aggravate venous thrombosis.

Powering antitumor immunity: challenges & promise at the intersection of immunometabolism & cancer immunotherapy

Since their approval, immune checkpoint inhibitors have drastically altered the landscape of cancer care. However, despite this substantial progress, many agents demonstrating considerable preclinical potential have failed to be successfully translated to the clinic. Therefore, an understanding of the processes underlying T cell responses will be crucial for the rational design of the next generation of immune checkpoint inhibitors. In parallel with these advances in tumor immunology, the field of immunometabolism has identified the importance of metabolic reprogramming during the initial steps of T cell activation in modulating clonal expansion, effector activity, and fate determination. Here, we will highlight the interplay between these processes, their suppression in the tumor-bearing state, and the putative mechanisms by which checkpoint blockade may restore metabolic reprogramming. Finally, we will discuss novel checkpoints under investigation and discovery-driven approaches to identify modulators of immune cell metabolism to synergize with new approaches to immune checkpoint inhibitors .

Texture Analysis of Computed Tomography Images in the Lung of Patients With Breast Cancer.

The aim of this study was to investigate whether the texture features of lung computed tomography images were altered by primary breast cancer without pulmonary metastasis. Texture analysis was performed on the regions of interest of lung computed tomography images from 36 patients with breast cancer and 36 healthy controls. Texture parameters between subjects with different clinical stages and hormone receptor (HR) statuses in patients with breast cancer were analyzed. Three texture parameters (mean, SD, and variance) were significantly different between patients with breast cancer and healthy controls and between preoperative and postoperative stages in patients with breast cancer. All 3 parameters showed an increasing trend under the tumor-bearing state. These parameters were significantly higher in the stage III + IV group than in the stage I + II group. The variance parameter was significantly higher in the HR-negative group than in the HR-positive group. Texture analysis may serve as a novel additional tool for discovering conventionally invisible changes in the lung tissue of patients with breast cancer.

Tumor-associated neutrophils suppress antitumor immunity of NK cells through the PD-L1/PD-1 axis.

Studies have begun to emerge showing the protumor effects of tumor-associated neutrophils (TANs) in tumorigenesis, which may involve dysfunction of NK cells. However, the mechanism through which these rebellious neutrophils modulate NK cell immunity in tumor-bearing state remains unclear. In the present study, we demonstrate that neutrophils can impair the cytotoxicity and infiltration capability of NK cells, and downregulate CCR1 resulting in the weakened infiltration capability of NK cells. Moreover, neutrophils can decrease the responsiveness of NK-activating receptors, NKp46 and NKG2D. Mechanistically, enhanced PD-L1 on neutrophils and PD-1 on NK cells, and subsequent PD-L1/PD-1 interactions were the main mechanisms determining the suppression of neutrophils in NK cell immunity. G-CSF/STAT3 pathway was responsible for PD-L1 upregulation on neutrophils, while IL-18 was essential for PD-1 enhancement on NK cells. The crosstalk between neutrophils and NK cells was cell-cell interaction-dependent. These findings suggest that neutrophils can suppress the antitumor immunity of NK cells in tumor-bearing status through the PD-L1/PD-1 axis, highlighting the importance of PD-L1/PD-1 in the inhibitory effect of neutrophils on NK cells. Targeting G-CSF/STAT3 and IL-18 signaling pathway may be potential strategies to inhibit residual tumor in tumor therapy.

Tumor Induced PD-L1 on Neutrophils Suppress the Antitumor Immunity of NK Cells via PD-L1/PD-1 Axis

In tumor-bearing state, the conversion of the system immune status makes the protumor function of neutrophils, and leading the suppression of NK cells cytotoxicity. The induced dysfunctional neutrophils could modulate the antitumor function of NK cells, but it is unclear whether and how the rebellious neutrophils modulate the NK cells anti-tumor function. Here we report that tumor-bearing neutrophils could impair NK cells cytotoxicity and the infiltration capability. Decreased CCR1 responsible for the weakened infiltration capability. Neutrophils could decrease the reactivity of NK activating receptor NKp46 and NKG2D. Induced PD-L1 expression (neutrophils) and PD-1 (NK cells) and the PD-L1/PD-1 axis were the main one mechanism of the suppression of NK cells immunity. Systemic increased G-CSF enhanced the expression of PD-L1, G-CSF/JAK2-STAT3 cell signaling pathway responsible to the upregulation of PD-L1. Tumor derived IL-18 enhances the PD-1 expression, block the IL-18 pathway by IL-18BP or knockdown the IL-18 expression by siRNA could both offset the IL-18 induced PD-1 expression. The neutrophils and NK cells crosstalk was cell-cell contact dependent, the affect of neutrophils on NK cells was disappeared when they were cultured in a separate system. These findings highlight the PD-L1/PD-1 signal on the immune suppression effect of neutrophils on NK cells. G-CSF and IL-18 producing might lead to a poor prognosis via different ways which cooperate to activate the immunosuppressive signal and weaken the antitumor affect of NK cells. Targeting G-CSF and IL-18 might be a potential approach to eliminate residual tumor cells in comprehensive strategy for tumor therapy. Funding Statement: This work was supported by National Natural Science Foundation of China (No. 81502461, 81502265), Natural Science Foundation of Hubei province (NO. 2016CFB340), Key Project of Wuhan Municipal Health Planning Commission Key Project (NO. WX15A08). Huazhong University of Science and Technology Double Top Construction, Project of International Cooperation (NO. 540-5001540013). Declaration of Interests: No potential conflicts of interest were disclosed. Ethics Approval Statement: BALB/c mice, 6 wks old, were purchased from Center of Medical Experimental Animals of Hubei Province (Wuhan, China) for studies approved by the Animal Care and Use Committee of Tongji Medical College (Wuhan, China).

Lack of interleukin-6 in the tumor microenvironment augments type-1 immunity and increases the efficacy of cancer immunotherapy.

Conquering immunosuppression in tumor microenvironments is crucial for effective cancer immunotherapy. It is well known that interleukin (IL)‐6, a pleiotropic cytokine, is produced in the tumor‐bearing state. In the present study, we investigated the precise effects of IL‐6 on antitumor immunity and the subsequent tumorigenesis in tumor‐bearing hosts. CT26 cells, a murine colon cancer cell line, were intradermally injected into wild‐type and IL‐6‐deficient mice. As a result, we found that tumor growth was decreased significantly in IL‐6‐deficient mice compared with wild‐type mice and the reduction was abrogated by depletion of CD8+ T cells. We further evaluated the immune status of tumor microenvironments and confirmed that mature dendritic cells, helper T cells and cytotoxic T cells were highly accumulated in tumor sites under the IL‐6‐deficient condition. In addition, higher numbers of interferon (IFN)‐γ‐producing T cells were present in the tumor tissues of IL‐6‐deficient mice compared with wild‐type mice. Surface expression levels of programmed death‐ligand 1 (PD‐L1) and MHC class I on CT26 cells were enhanced under the IL‐6‐deficient condition in vivo and by IFN‐γ stimulation in vitro. Finally, we confirmed that in vivo injection of an anti‐PD‐L1 antibody or a Toll‐like receptor 3 ligand, polyinosinic‐polycytidylic acid, effectively inhibited tumorigenesis under the IL‐6‐deficient condition. Based on these findings, we speculate that a lack of IL‐6 produced in tumor‐bearing host augments induction of antitumor effector T cells and inhibits tumorigenesis in vivo, suggesting that IL‐6 signaling may be a promising target for the development of effective cancer immunotherapies.

Aerobic and resistance training dependent skeletal muscle plasticity in the colon-26 murine model of cancer cachexia

PurposeThe appropriate mode of exercise training for cancer cachexia is not well-established. Using the colon-26 (C26) mouse model of cancer cachexia, we defined and compared the skeletal muscle responses to aerobic and resistance training. MethodsTwelve-month old Balb/c mice were initially assigned to control, aerobic training (AT; wheel running), or resistance training (RT; ladder climbing) (n=16–17/group). After 8weeks of training, half of each group was injected with C26 tumor cells, followed by 3 additional weeks of training. Body composition and neuromuscular function was evaluated pre- and post-training. Muscles were collected post-training and analyzed for fiber cross-sectional area (CSA), Akt–mTOR signaling, and expression of insulin-like growth factor-I (IGF-I) and myogenic regulatory factors. ResultsTotal body mass decreased (p<0.05) in C26 (−8%), AT+C26 (−18%), and RT+C26 (−15%) but not control. Sensorimotor function declined (p<0.05) in control (−16%), C26 (−13%), and RT+C26 (−23%) but not AT+C26. Similarly, strength/body weight decreased (p<0.05) in control (−7%), C26 (−21%), and RT+C26 (−10%) but not AT+C26. Gastrocnemius mass/body weight tended to be greater in AT+C26 vs. C26 (+6%, p=0.09). Enlargement of the spleen was partially corrected in AT+C26 (−27% vs. C26, p<0.05). Fiber CSA was lower in all C26 groups vs. control (−32% to 46%, p<0.05); however, the effect size calculated from C26 and AT+C26 was large (+24%, d=1.04). Phosphorylated levels of mTOR in AT+C26 exceeded C26 (+32%, p<0.05). RT+C26 showed greater mRNA expression (p<0.05) of IGF-IEa (+79%) and myogenin (+126%) with a strong tendency for greater IGF-IEb (+127%, p=0.069) vs. control. ConclusionsAerobic or resistance training was unable to prevent tumor-induced body weight loss. However, aerobic training may have preserved function, reduced the inflammatory response of the spleen, and marginally rescued muscle mass possibly through activation of mTOR. Aerobic training may therefore have therapeutic value for patients with cancer cachexia. In contrast, resistance training induced the expression of genes associated with muscle damage and repair. This gene response may be supportive of excessive stress generated by high resistance loading in a tumor-bearing state.

Ghrelin relieves cancer cachexia associated with the development of lung adenocarcinoma in mice

Cancer cachexia is a multifactorial, critical illness syndrome characterized by an ongoing loss of skeletal muscle and adipose tissue. The reductions in body weight and skeletal muscle mass are important prognostic indicators for cancer patients that are refractory to current therapies. Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor, is produced in the stomach, stimulates food intake and growth hormone secretion, suppresses inflammation, and prevents muscle catabolism. We investigated the pharmacological potential of ghrelin in the treatment of cancer cachexia by using urethane-treated, bronchioalveolar epithelium-specific Pten-deficient mice that developed lung adenocarcinomas. Ghrelin or phosphate-buffered saline was given to mice daily for four weeks beginning at five months after urethane injection, which corresponded to the time point of lung adenocarcinoma formation. Ghrelin inhibited the inductions of C-reactive protein, tumor necrosis factor-α, interleukin-1β, and interleukin-6, mitigated the reduction of food intake and fat mass, and consequently ameliorated body weight loss in the mouse model of lung adenocarcinoma. We also demonstrated that skeletal muscle mass and muscle contraction force in both fast-twitch muscle and slow-twitch muscle were retained in ghrelin-treated mice in conjunction with an upregulation of local insulin-like growth factor 1/Akt signaling. In addition, ghrelin administration reduced the expressions of phosphorylated-p38 mitogen-activated protein kinase, phosphorylated-nuclear factor-kappa B, Forkhead box protein O1, muscle RING-finger protein-1, and F-Box protein 32 in the lysates of skeletal muscle in the tumor-bearing state. Our results indicate that ghrelin administration exerts a protective effect against cancer cachexia by ameliorating skeletal muscle wasting and regulating systemic inflammation.

Effects of tumor bearing on serum and liver lipid levels in RCN-9-implanted rats

Objectives: To investigate the effects of a bearing of RCN-9, a transplantable rat colon adenocarcinoma, on lipid metabolism, changes in serum and liver lipid levels were investigated in RCN-9-implanted rats. In the tumor-bearing state, decreases in food intake and body weight are seen as a result of a cancer-induced cachexia; therefore, a pair-feeding study was conducted to investigate the effects of food restriction on tumor-bearing in RCN-9-implanted rats.

Neutrophils with protumor potential could efficiently suppress tumor growth after cytokine priming and in presence of normal NK cells.

In tumor-bearing state, the function of neutrophils is converted from tumor-suppressing to tumor-promoting. Here we report that priming with IFN-γ and TNF-α could convert the potential of neutrophils from tumor-promoting to tumor-suppressing. The neutrophils with protumor potential have not lost their responsiveness to IFN-γ and TNF-α. After priming with IFN-γ and TNF-α, the potential of the neutrophils to express Bv8 and Mmp9 genes was reduced. Conversely, the tumor-promotional neutrophils recovered the expression of Rab27a and Trail, resumed the activation levels of PI3K and p38 MAPK pathways in response to stimuli, and expressed higher levels of IL-18 and NK-activating ligands such as RAE-1, MULT-1, and H60. Therefore, the anti-tumor function of the neutrophils was augmented, including the cytotoxicity to tumor cells, the capability of degranulation, and the capacity to activate NK cells. Since the function of NK cells is impaired in tumor-bearing state, the administration of normal NK cells could significantly augment the efficiency of tumor therapy based on neutrophil priming. These findings highlight the reversibility of neutrophil function in tumor-bearing state, and suggest that neutrophil priming by IFN-γ/TNF-α might be a potential approach to eliminate residual tumor cells in comprehensive strategy for tumor therapy.

&amp;#946;-Hydroxy-&amp;#946;-Methylbutyrate as a Countermeasure for Cancer Cachexia: A Cellular and Molecular Rationale

Cancer cachexia is a life-threatening condition characterized by involuntary body weight loss and skeletal muscle wasting. In addition to being associated with poor prognosis and reduced survival, patients with cachexia exhibit a critical loss of physical function that impinges upon their ability to perform basic activities of daily living. Consequently, there is a loss of independence and a drastically reduced quality of life. Despite being a major unmet medical need of patients, very few treatment options exist. Maintaining muscle mass represents an important objective in the cancer patient trajectory not only because it relates to one's capacity to perform activities of daily living, but also because muscle preservation may be a critical determinant of survival while in a tumor-bearing state. In this regard, research has been directed towards identifying countermeasures effective in preserving muscle. With respect to nutritional approaches, administration of the leucine metabolite β-hydroxy-β-methylbutyrate (HMB) could be a viable component in multi-modal therapies targeting cancer cachexia. Evidence suggests that HMB treatment promotes regenerative events (i.e. myogenic program), suppresses protein degradation, and activates signaling pathways preceding protein synthesis and skeletal muscle growth. HMB therefore, could conceivably act on key regulatory events driving cancer cachexia, thereby favoring muscle growth/preservation. In this review, we take a mechanistic approach in making a case for the use of HMB provision as a possible therapeutic strategy for cancer cachexia by highlighting the cellular and molecular aspects of HMB function.

The Key Role of IL-6–Arginase Cascade for Inducing Dendritic Cell–Dependent CD4+ T Cell Dysfunction in Tumor-Bearing Mice

Evaluation of immune dysfunction during the tumor-bearing state is a critical issue in combating cancer. In this study, we initially found that IL-6, one of the cachectic factors, suppressed CD4(+) T cell-mediated immunity through downregulation of MHC class II by enhanced arginase activity of dendritic cells (DC) in tumor-bearing mice. We demonstrated that administration of Ab against IL-6R (anti-IL-6R mAb) greatly enhanced T cell responses and inhibited the growth of tumor in vivo. We also found that IL-6 upregulated the expression of arginase-1 and arginase activity of DC in vitro. Tumor-infiltrating CD11c(+) DC exhibited upregulated mRNA expression of arginase-1 but reduced expression of MHC class II in parallel with the increase in serum IL-6 levels at the late stage in tumor-bearing hosts. However, the administration of anti-IL-6R mAb into tumor-bearing mice inhibited both the downmodulation of MHC class II and the upregulation of arginase-1 mRNA levels in DC. Furthermore, we noted that N(ω)-hydroxy-L-arginine or L-arginine, an arginase-1 inhibitor, blocked the reduction in MHC class II levels on CD11c(+) DC during the tumor-bearing state. Finally, we demonstrated that the administration of N(ω)-hydroxy-L-arginine at the peritumor site significantly enhanced CD4(+) T cell responses and inhibited tumor growth. Thus, IL-6-mediated arginase activation and the subsequent reduction in MHC class II expression on DC appeared to be critical mechanisms for inducing dysfunction of the immune system in the tumor-bearing state. Blockade of the IL-6-arginase cascade is a promising tool to overcome the dysfunction of antitumor immunity in tumor-bearing hosts.

O2-009 - Retrospective Analysis of Clinical Features of 5-Year-Survival Patients with Advanced Non-Small-Cell Lung Cancer (NSCLC)

ABSTRACT Background Recently, prognosis in patients with advanced NSCLC will improve much better than before. In these patients, several patients survive with tumor-bearing state for 5 years or more. Purpose We retrospectively examined clinical features in patients with advanced NSCLC who survived for 5 years or more. Patients and methods We extracted 5 years or more survival patients from those who met the following criteria: those with histologically proven NSCLC; those who received first-line chemotherapy between 1 January 2004 and 31 January 2007; those who had advanced stages including stage IIIB (unsuitable for surgical treatment or radical thoracic radiation therapy), stage IV and post-surgical recurrence; and those who had measurable or evaluable lesions. Perioperative chemotherapy was not counted as first-line chemotherapy. The survival time was defined as the time from the initiation date of first-line chemotherapy to the date of death or last follow-up. The survival time data were updated on 31 January 2012. We collected various data from their clinical records as follows: baseline demographics information including sex, PS, stage and histology; chemotherapy including regimen and number of cycles and dose; EGFR genetic-testing. Results A total of 228 patients met the above criteria. The median survival time was 12.9 months. Seventeen (7.4%) patients—8 males and 9 females, with a median age of 66 (range: 52–80)—survived for 5 years or more. Among these, six had a performance status (PS) of 0 and 11 had a PS of 1; all had adenocarcinoma; 12 had never smoked and 5 were current smokers. Eight patients had stage IV, 6 had relapsed after surgery and 3 had stage IIIB with malignant pleural effusion. Twelve patients underwent EGFR testing: three had exon 19 deletions, two had L858R mutations, two had other mutations and five had the wild type. These 17 survivors may be categorized into four types: (a) patients (n = 4) who responded to EGFR-TKIs only; (b) those (n = 3) who responded to two or more regimens, including EGFR-TKIs; (c) those (n = 7) who responded to one or more regimens but not EGFR-TKIs; and (d) those (n = 3) who had very slow-growing lung cancers. Conclusion Most patients who survived for 5 years or more responded to one or more regimens for a long period.

Contribution of an aging environment towards a proinflammatory tumor-like milieu (54.4)

Abstract Chronic inflammation associated with aging is termed inflamm-aging. It manifests as a rise in many proinflammatory mediators and contributes to a decline in immune function. Unregulated inflammasome activation initiates an inappropriate inflammatory response. It is particularly imperative to understand inflammasome dysregulation in the elderly (&amp;gt;65 yrs), since it is a likely basis of immune dysfunction. Analyses of freshly isolated memory CD4+ and CD8+ splenic T cells demonstrated that even without further activation, inflammasome genes were already significantly up-regulated in old mice compared to young, including factors critical to myeloid-derived suppressor cell (MDSC) expansion including S100a8, S100a9, IL-1β, IL-13 and IL-6. A corresponding 2-3 fold increase in CD11b+Gr1+cells was observed in the spleens of old naïve mice compared to young. Importantly, cells with the CD11b+Gr1+ phenotype from old mice, unlike young, were functionally MDSCs and suppressed T cell proliferation. Therefore, the immunosuppressive environment of the tumor-bearing host also appears to be operative in aging, even in the absence of tumor. We hypothesize that constituitive activation of inflammasome complex results in a chronic inflammatory state, altering immune responses in the elderly similarly to the tumor-bearing state. Preemptive reversal of inflammasome-induced MDSCs may enhance T cell immunosurveillance in the elderly, a population with a heightened susceptibility to malignancy.

In vitro-activated tumor-bearing host T cells and the effectiveness of tumor vaccine immunotherapy

BACKGROUND AND OBJECTIVEVaccination during periods of lymphopenia may facilitate immune responses to weak self-antigens and enhance antitumor immunity. The objective of this study was to determine the effectiveness of tumor vaccine immunotherapy combined with immune reconstruction using tumor-bearing host immune cells in lymphopenia, and to investigate the role of tumor-bearing host T cells activated in vitro during immunotherapy.DESIGN AND SETTINGAnimal study conducted in the First Affiliated Hospital of Xi’an Jiaotong University from January 2009 to January 2010.PATIENTS AND METHODSLymphopenia was induced by cyclophosphamide. A reconstituted immune system with different syngeneic lymphocytes was employed, including lymphocytes from naïve rats (unsensitized group), tumor-bearing rats (tumor-bearing group), and tumor-bearing rats activated in vitro (activated group). All rats were immunized with granulocyte-macrophage colony-stimulating factor (GM-CSF)-modified NuTu-19 ovarian cancer (GM-CSF/NuTu-19) cells. Tumor vaccine-draining lymph nodes (TVDLNs) were harvested, and then stimulated to induce effector T cells (TE). TE were then adoptively transferred to rats bearing a 3-day pre-established abdominal tumor (NuTu-19), and the survival rate was calculated.RESULTSCompared with the unsensitized group, the levels of interleukin-2 (IL-2) were significantly lower in the tumor-bearing group, whereas that of IL-4 were significantly higher (P<.05). The number of CD4+ T cells secreting interferon-γ and the specific cytotoxicity of CD8+ cytotoxic T lymphocytes were significantly lower (P<.05). The survival was significantly higher in the activated group compared with the other groups.CONCLUSIONSLymphocytes from tumor-bearing rats activated in vitro can effectively reverse the immunosuppressive effects of tumor-bearing hosts.

Acquired STAT4 deficiency as a consequence of cancer chemotherapy

AbstractSignal Transducer and Activator of Transcription 4 (STAT4) is a transcription factor that is activated by IL-12 signaling and promotes Th1-cell differentiation and IFN-γ production. Defective IFN-γ production because of STAT4 mRNA and protein deficiency occurs after autologous stem cell transplantation for lymphoma. In the present study, we investigated the mechanisms of STAT4 deficiency in lymphoma patients. The tumor-bearing state is not responsible, because STAT4 levels were not significantly different in PBMCs obtained from healthy control subjects compared with those from lymphoma patients before treatment. STAT4 protein levels were significantly decreased in PBMCs and T cells obtained from lymphoma patients after standard-dose chemotherapy. Furthermore, treatment of control PBMC cultures or a natural killer cell line with chemotherapy drugs in vitro also resulted in reduced STAT4 protein and diminished, IL-12–induced IFN-γ production. Translation of STAT4 protein was not impaired in chemotherapy-treated cells, whereas the STAT4 protein half-life was significantly reduced. Chemotherapy drugs promoted the ubiquitination and proteasomal degradation of STAT4. Treatment with the proteasome inhibitor bortezomib reversed chemotherapy-induced STAT4 deficiency and defective IFN-γ production. We conclude that acquired STAT4 deficiency in lymphoma patients is a consequence of treatment with chemotherapy, results that have important implications for the design of optimal immunotherapy for lymphoma.

Single and combined supplementation of glutamine andn-3 polyunsaturated fatty acids on host tolerance and tumour response to 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxy-camptothecin (CPT-11)/5-fluorouracil chemotherapy in rats bearing Ward colon tumour

Prior reports suggest that during irinotecan (7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxy-camptothecin; CPT-11) chemotherapy in laboratory rats, the anti-tumour efficacy and diarrhoea toxicity could be modulated by n-3 PUFA and glutamine, respectively. We further examined how these two dietary elements, when provided individually and in combination, would affect the efficacy of a cyclical regimen of CPT-11/5-fluorouracil (5-FU), an accepted combination regimen for colorectal cancer. Prior to initiating chemotherapy, diets enriched either with glutamine (2 %, w/w total diet) or n-3 PUFA (0.88 %, w/w total diet) alone, inhibited Ward colon tumour growth (P < 0.05). These diets also completely or partially normalized the changes in peripheral leucocyte counts associated with the tumour-bearing state (e.g. neutrophil proportion/concentration and lymphocyte proportion). During chemotherapy, either glutamine- or n-3 PUFA-enriched diet enhanced tumour chemo-sensitivity, and reduced body weight loss, anorexia and muscle wasting (v. animals fed control diet, P < 0.05). Surprisingly, providing both glutamine and n-3 PUFA together did not confer a greater benefit on tumour inhibition either in the presence or absence of chemotherapy; individual benefits associated with single treatments, particularly in respect to host nutritional status (i.e. body weight, food intake and muscle weight) and immune (peripheral leucocyte counts) features were instead partially or completely lost when these two nutrients were combined. These results draw into question the common assumption that there are additive or synergistic benefits of combinations of nutrients, which are beneficial on an individual basis, and suggest that co-supplementation with glutamine and n-3 PUFA is not indicated during chemotherapy with CPT-11 and 5-FU.

Ligation of tumour-produced mucins to CD22 dramatically impairs splenic marginal zone B-cells

CD22 [Siglec-2 (sialic acid-binding, immunoglobulin-like lectin-2)], a negative regulator of B-cell signalling, binds to alpha2,6- sialic acid-linked glycoconjugates, including a sialyl-Tn antigen that is one of the typical tumour-associated carbohydrate antigens expressed on various mucins. Many epithelial tumours secrete mucins into tissues and/or the bloodstream. Mouse mammary adenocarcinoma cells, TA3-Ha, produce a mucin named epiglycanin, but a subline of them, TA3-St, does not. Epiglycanin binds to CD22 and inhibits B-cell signalling in vitro. The in vivo effect of mucins in the tumour-bearing state was investigated using these cell lines. It should be noted that splenic MZ (marginal zone) B-cells were dramatically reduced in the mice bearing TA3-Ha cells but not in those bearing TA3-St cells, this being consistent with the finding that the thymus-independent response was reduced in these mice. When the mucins were administered to normal mice, a portion of them was detected in the splenic MZ associated with the MZ B-cells. Furthermore, administration of mucins to normal mice clearly reduced the splenic MZ B-cells, similar to tumour-bearing mice. These results indicate that mucins in the bloodstream interacted with CD22, which led to impairment of the splenic MZ B-cells in the tumour-bearing state.

A clinical grade poly I:C-analogue (Ampligen ®) promotes optimal DC maturation and Th1-type T cell responses of healthy donors and cancer patients in vitro

Maturation of dendritic cells (DC) can be triggered in vitro by inflammatory cytokines or Toll-like receptor (TLR) ligands such as CpG or polyI:C. Corresponding, well-characterized agents which can be applied in clinical settings are sparse. We have evaluated a clinical grade, non-toxic analogue of polyI:C, poly(I:C 12U) (Ampligen ®), as a potential adjuvant for cancer immunotherapy, for its ability to drive maturation of human myeloid DC. Our results provide evidence that poly(I:C 12U) is effective in inducing optimal phenotypic (elevated levels of MHC-Class I/Class II, CD83, CCR7, CD86 and CD40 molecules) and functional maturation of human DC in vitro, capable of promoting the production of the inflammatory (Th1-type) cytokine IL-12, with significantly lower levels of IL-10 production, compared to that induced by the parent compound polyI:C. Importantly, poly(I:C 12U) has a comparable effect on the maturation and function of DC derived either from healthy donors or cancer patients indicating that it is able to overcome any immune suppressive factors associated with the tumour bearing state. These characteristics make poly(I:C 12U) a suitable agent for use as an adjuvant in cancer directed immunotherapeutic regimes.