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Background: The combination of chemotherapy with the vascular endothelial growth factor (VEGF) antibody bevacizumab is a standard of care in advanced colorectal cancer (CRC). However, biomarkers predicting outcome of bevacizumab-containing treatment are lacking. As angiopoietin-2 (Ang-2) is a key regulator of vascular remodelling in concert with VEGF, we investigated its role as a biomarker in metastatic CRC. Methods: Serum Ang-2 levels were measured in 33 healthy volunteers and 90 patients with CRC. Of these, 34 had metastatic disease and received bevacizumab-containing therapy. To determine the tissue of origin of Ang-2, quantitative real-time PCR was performed on microdissected cryosections of human CRC and in a murine xenograft model of CRC using species-specific amplification. Results: Ang-2 originated from the stromal compartment of CRC tissues. Serum Ang-2 levels were significantly elevated in patients with metastatic CRC compared with healthy controls. Amongst patients receiving bevacizumab-containing treatment, low pre-therapeutic serum Ang-2 levels were associated with a significant better response rate (82 vs 31% P

Purpose: Cyclin D1, a key cell cycle regulator, is overexpressed in multiple types of cancer. Such tumor-associated genes may be useful targets for cancer immunotherapy. Nevertheless, it had previously been suggested that efficient T cells recognizing cyclin D1-derived epitopes are absent from the repertoire because of thymic deletion. We attempted to induce autologous CTL from healthy donors and patients with cyclin D1-overexpressing tumors using a highly efficient T-cell expansion system based on CD40-activated B cells as antigen-presenting cells.Experimental Design: Cyclin D1-derived, HLA-A*0201–restricted epitopes were predicted by multiple computer algorithms, screened in HLA-A2-binding assays, and used for T-cell stimulation. The generated CTL lines and clones were analyzed by IFN-γ enzyme-linked immunosorbent spot assay or cytolysis assay.Results: After screening, at least two naturally processed and presented HLA-A*0201–binding cyclin D1 epitopes were identified. CTL specific for these epitopes could be successfully generated from HLA-A2+ donors. T cells efficiently recognized target cells pulsed with the cognate peptide and cyclin D1-expressing tumor cell lines in an HLA-A*0201–restricted manner. More importantly, HLA-A*0201–matched, primary cyclin D1+ tumor cells were efficiently recognized by cyclin D1-specific CTL. These CTL could be generated from patients with mantle cell lymphoma and cyclin D1+ colon cancer.Conclusions: These results underscore that cyclin D1 needs to be considered as a target for broad-based antitumor immunotherapy.

Stage IV colorectal cancer is usually an incurable disease. However, patients with resectable metastases have 5-year disease-free survival rates of up to 30%. Even with primarily irresectable disease, cure can be achieved in patients who become operable after neoadjuvant treatment. To improve the prognosis of these patients, highly effective neoadjuvant regimens need to be developed.Here, we report the case of a 62-year-old male patient who had been diagnosed with International Union against Cancer (UICC) stage III colon cancer 7 years previously and now presented with a large, irresectable liver metastasis and enlarged perihepatic lymph nodes. After neoadjuvant treatment with cetuximab, bevacizumab and XELOX, the patient showed a complete remission and underwent surgery. Histopathologically, the resected tissue and lymph nodes were free of residual tumor.To our knowledge, this is the first report of a complete pathological response in a patient with irresectable colorectal cancer after intensive chemotherapy/anti-EGFR/ VEGF antibody therapy. This combination regimen may help to improve the survival rates for patients with irresectable disease.

Purpose: We conducted a phase I/II randomized trial to evaluate the clinical and immunologic effect of chemotherapy combined with vaccination in primary metastatic colorectal cancer patients with a carcinoembryonic antigen–derived peptide in the setting of adjuvants granulocyte macrophage colony-stimulating factor, CpG-containing DNA molecules (dSLIM), and dendritic cells. Experimental Design: HLA-A2–positive patients with confirmed newly diagnosed metastatic colorectal cancer and elevated serum carcinoembryonic antigen (CEA) were randomized to receive three cycles of standard chemotherapy (irinotecan/high-dose 5-fluorouracil/leucovorin) and vaccinations with CEA-derived CAP-1 peptide admixed with different adjuvants [CAP-1/granulocyte macrophage colony-stimulating factor/interleukin-2 (IL-2), CAP-1/dSLIM/IL-2, and CAP-1/IL-2]. After completion of chemotherapy, patients received weekly vaccinations until progression of disease. Immune assessment was done at baseline and after three cycles of combined chemoimmunotherapy. HLA-A2 tetramers complexed with the peptides CAP-1, human T-cell lymphotrophic virus type I TAX, cytomegalovirus (CMV) pp65, and EBV BMLF-1 were used for phenotypic immune assessment. IFN-γ intracellular cytokine assays were done to evaluate CTL reactivity. Results: Seventeen metastatic patients were recruited, of whom 12 completed three cycles. Therapy resulted in five complete response, one partial response, five stable disease, and six progressive disease. Six grade 1 local skin reactions and one mild systemic reaction to vaccination treatment were observed. Overall survival after a median observation time of 29 months was 17 months with a survival rate of 35% (6 of 17) at that time. Eight patients (47%) showed elevation of CAP-1–specific CTLs. Neither of the adjuvants provided superiority in eliciting CAP-1–specific immune responses. During three cycles of chemotherapy, EBV/CMV recall antigen–specific CD8+ cells decreased by an average 14%. Conclusions: The presented chemoimmunotherapy is a feasible and safe combination therapy with clinical and immunologic efficacy. Despite concurrent chemotherapy, increases in CAP-1–specific T cells were observed in 47% of patients after vaccination.

Today, many patients with lymphoma are cured by polychemotherapy and irradiation. However, residual masses are frequently observed after treatment and discrimination between vital tumor and inactive fibrotic tissue by computed tomography or magnetic resonance tomography is often not possible. 18 F-Fluorodeoxyglucose (FDG) positron emission tomography (PET) is a metabolic imaging modality that is able to detect active lymphoma lesions. The application of PET may play a crucial role in identifying patients with residual disease and contribute valuable prognostic information. To assess the prognostic implications of PET in the post-therapeutic setting, we performed a MedLine Search and reviewed the current available studies on this important issue together with our own data.

PURPOSE: Micrometastatic disease in bone marrow is of prognostic significance in colorectal cancer patients. However, detection rates of standard immunocytology are relatively low. We used magnetic activated cell sorting (MACS), a highly sensitive method, to increase detection rates and correlated the presence of cytokeratin (CK)-expressing cells with clinical parameters. PATIENTS AND METHODS: Bone marrow was obtained from 51 consecutive patients with newly diagnosed colorectal adenocarcinoma who underwent primary surgery and 18 control subjects. International Union Against Cancer (UICC) stage I disease was diagnosed in 11 patients, stage II disease was diagnosed in 14 patients, stage III disease was diagnosed in 12 patients, and stage IV disease was diagnosed in 14 patients. CK-positive cells were enriched and stained with magnetically labeled CAM 5.2 antibodies directed to CK 7 and 8. RESULTS: CK-positive cells were found in 33 (65%) patients and were absent in 18 (35%). Four of 11 (36%) patients with UICC stage I disease, nine of 14 (64%) with stage II diease, eight of 12 (67%) with stage III disease, and 12 of 14 (86%) with stage IV disease were CK-positive. Epithelial cells were more frequently found in pT3/4 (72%) than in pT1/2 (36%) tumors (P = .026), but there was no difference for lymph node status. CK-positive patients had a higher chance for elevated carcinoembryonic antigen (85% v 15%, P = NS) and CA 19-9 levels (92% v 8%, P = .019). There were no significant differences in CA 72-4, sex, age, tumor grading, or tumor localization regarding the presence of CK-positive cells. All control subjects were CK-negative. CONCLUSION: In searching for micrometastases in colorectal cancer patients, we have achieved high detection rates by using MACS. The presence of these cells correlated significantly with tumor stage, tumor extension, and the tumor marker CA 19-9.

High-dose methotrexate (HDMTX) is a component of many cancer treatment regimens. Despite careful management, delayed renal clearance, followed by extremely high serum levels with potentially life-threatening toxicity can occur. In the present study, we report our results of carboxypeptidase-G2 (CPDG2) rescue in 8 patients with delayed methotrexate elimination and renal impairment after HDMTX therapy for lymphoma or osteosarcoma. A dose of 50 U/kg CPDG2 was administered. MTX plasma levels decreased rapidly and recovery of renal function was observed in all patients. No patient developed severe WHO grade 4 MTX toxicity. CPDG2 provides an alternative route of MTX elimination by converting it to inactive and non-toxic metabolites. CPDG2 rescue was well tolerated, safe and very effective in preventing severe or life-threatening MTX toxicity.

The detection of isolated tumor cells (ITC) in the bone marrow of patients with epithelial malignancies is an independant prognostic factor for several entities as breast cancer, colorectal cancer or non-small lung cancer. However, with conventional immunocytology using Ficoll density gradient and APAAP staining, only a small proportion of the bone marrow samples can be scanned for cytokeratin-positive (CK+) cells. To improve detection rates, we evaluated the enrichment of ITC by magnetic activated cell sorting (MACS) compared to regularly stained cytospins. Recovery experiments with a CK+ breast cancer cell line (SKBR3) were performed to calculate the MACS enrichment rate. Bone marrow was obtained by aspiration from 20 patients with carcinomas of epithelial origin and from 17 controls. ITC were enriched and stained with magnetically labeled CAM 5.2 antibodies directed to cytokeratin 7 and 8. MACS of SKBR3 seeded in peripheral blood revealed average recovery rates of 62% and 48% and average enrichment factors of 104-fold and 8139-fold of the CK+ cells after one and after two separations, respectively. After immunomagnetic enrichment, CK+ cells were detected in 16 of 20 (80%) cancer patients, whereas only 7 (35%) patients showed CK+ cells without magnetic enrichment (P=0.002). Ten of twelve (83%) patients with metastatic disease (stage M1) and six of eight (75%) patients without any overt metastases (M0) had CK+ cells in their bone marrow. None of the negative controls showed any CK+ cells. Enrichment with magnetically labeled anti cytokeratin antibodies increases the detection rate of epithelial cells in bone marrow of cancer patients compared to immunocytology.

Tie2-expressing monocytes (TEM) promote tumor angiogenesis and growth in experimental cancer models. The role of TEM in cancer patients is unknown. We studied TEM in healthy volunteers and colorectal cancer (CRC) patients. Although TEM were detectable in the blood and tumor lesions of CRC patients, their frequency and functional phenotype showed no correlation with levels of angiopoietin-2 or vascular endothelial growth factor, microvessel density, tumor markers, tumor stage, or outcome of antiangiogenic therapy. These unexpected findings are at odds with murine tumor models and question the diagnostic or therapeutic value of TEM in human cancer.

Background Sunitinib monotherapy in pretreated patients with advanced gastric cancer (AGC) was investigated. Preplanned analyses of tumour biomarkers on treatment outcome were performed. Patients and methods Patients received sunitinib 50 mg/day for 4 weeks with 2 weeks rest until disease progression or unacceptable toxicity. The primary end-point was objective response rate (ORR). Secondary end-points included progression-free survival (PFS), overall survival (OS) and safety. Results Fifty-two patients were enrolled and treated (safety population, SP). In the intention to treat population ( n = 51); the ORR was 3.9%, median PFS was 1.28 months [95% CI, 1.18–1.90], median OS was 5.81 months [95% CI, 3.48–12.32], the estimated one-year survival rate was 23.7% [95%CI: 12.8–36.5]. In subgroup analyses, tumour VEGF-C expression compared with no expression was associated with significantly shorter median PFS (1.23 versus 2.86 months, logrank p = 0.0119) but there was no difference in tumour control rate ( p = 0.142). In the SP, serious adverse events occurred in 26 patients, leading to 13 deaths, all sunitinib unrelated. Thirty-eight patients died from progressive disease, nine died Conclusion Sunitinib monotherapy was associated with limited tumour response and good/moderate tolerability in this setting.

Early treatment failure is still a clinical challenge despite high cure rates in Hodgkin lymphoma (HL) patients. To identify the biological risk factors predicting early treatment failure, we performed a retrospective case-control study. Forty-seven pretherapeutic serum samples were available from 47 advanced stage HL patients with early treatment failure and from 47 matched controls in complete remission. All patients were treated within German Hodgkin Study Group phase 3 trials. Matching was done according to treatment, stage, age, gender, International Prognostic Score (IPS) and histological subtype. Pretreatment serum levels of 30 cytokines, chemokines and soluble receptors were determined using immunoassays and flow cytometer based cytometric bead arrays. Only interleukin-10 serum levels were significantly associated with early treatment failure after statistical correction for multitesting (paired-sign test, p = 0.0008). In summary, pretherapeutic interleukin-10 levels are associated with early treatment failure within 12 months after the end of treatment in advanced stage HL independently from known clinical factors such as age or IPS.

The CC thymus and activation-related chemokine (TARC) is a protein, which is highly expressed by Reed-Sternberg cells in Hodgkin's disease and is found in the majority of Hodgkin's disease patients. Within several trials conducted by the German Hodgkin study group, 62 Hodgkin's disease patients were elected based on availability of serum samples post and prior therapy to assess TARC levels by ELISA. TARC levels from 33 patients with continuous complete response (CCR), 20 patients with relapse, and nine patients with progressive disease (PD) were correlated with freedom from treatment failure and survival. As defined in healthy donors (mean value ± 2× SD), a TARC level of >500 pg/mL was considered as elevated. The median TARC levels of all patients at baseline and after completed primary treatment were 5,803 pg/mL (range, 116-73,074 pg/mL) and 663 pg/mL (50-24,709 pg/mL), respectively. TARC levels of patients with PD were higher than those of patients with CCR at baseline and after therapy. Baseline TARC correlated significantly with stage (P = 0.019), erythrocyte sedimentation rate (P = 0.004), leukocyte count (P < 0.001), and lymphocyte count (P = 0.026). A TARC level of >2,000 pg/mL after completed treatment was a significant risk factor for poorer survival (P = 0.02) but not for relapse. In conclusion, monitoring serum TARC levels in Hodgkin's disease patients may add valuable information about therapy success in Hodgkin's disease patients, especially those with PD and should therefore be prospectively evaluated in future trials.

Topotecan, a topoisomerase-I inhibitor is an active drug in the treatment of AML and MDS. To evaluate its toxicity and efficacy in a combination regimen with cytarabine, we conducted a clinical phase I/II trial in patients with relapsed acute myeloid leukemia (AML) or relapsed or newly diagnosed MDS RAEB, RAEB-t or CMML. Twenty-one patients (11 AML, 10 MDS/CMML) entered the study and were treated with 1.25 mg/m2 topotecan as continuous intravenous infusion daily for 5 days and cytarabine 1.0 g/m2 by infusion over 2 h daily for 5 days (TA). Cycles were repeated on day 28. The median observation time was 131 weeks (range: 36-196 weeks). A total of 37 cycles of TA were administered. In 1 patient, the dose of TA had to be reduced and in 1 patient, there was a treatment delay for the second cycle, both because of hematologic toxicity. The most frequent non-hematologic side-effect of TA was fever, which occurred in 17 patients (89%) with temperatures over 38 degrees C. None of the patients died due to any treatment-related toxicities, but 2 patients (10%) died within 1 month due to disease progression. A CR was achieved in 7 patients (33%), 3 of whom were MDS and 4 AML. A partial remission was reported in 8 patients (38%), no change of disease in 2 patients (10%) and progressive disease in 4 patients (19%). The median remission duration was 18 weeks (range 2-161 weeks) for MDS patients and 11 weeks (range 2-49 weeks) for AML patients. The time to progression for patients of 60 years and older (n = 10) was 16 weeks (range 2-49 weeks) and the survival was 32 weeks (range 2-119 weeks). TA is a feasible and efficacious chemotherapeutic combination for the treatment of MDS RAEB, RAEB-t, CMML and AML. For patients of 60 years and older, this regimen is also a safe option.

Regulatory T cells (T(reg) cells) are increased in context of malignancies and their expansion can be correlated with higher disease burden and decreased survival. Initially, interleukin 2 (IL-2) has been used as T-cell growth factor in clinical vaccination trials. In murine models, however, a role of IL-2 in development, differentiation, homeostasis, and function of T(reg) cells was established. In IL-2 treated cancer patients a further T(reg)-cell expansion was described, yet, the mechanism of expansion is still elusive. Here we report that functional T(reg) cells of a naïve phenotype--as determined by CCR7 and CD45RA expression--are significantly expanded in colorectal cancer patients. Treatment of 15 UICC stage IV colorectal cancer patients with IL-2 in a phase I/II peptide vaccination trial further enlarges the already increased naïve T(reg)-cell pool. Higher frequencies of T-cell receptor excision circles in naïve T(reg) cells indicate IL-2 dependent thymic generation of naïve T(reg) cells as a mechanism leading to increased frequencies of T(reg) cells post IL-2 treatment in cancer patients. This finding could be confirmed in naïve murine T(reg) cells after IL-2 administration. These results point to a more complex regulation of T(reg) cells in context of IL-2 administration. Future strategies therefore might aim at combining IL-2 therapy with novel strategies to circumvent expansion and differentiation of naïve T(reg) cells.

4133 Background: The combination of chemotherapy and the anti-VEGF antibody bevacizumab (BV) is the current standard treatment for advanced colorectal cancer (CRC). Previous efforts to identify bio...