Influence of comorbidity, age and performance status on treatment efficacy and safety of cetuximab plus irinotecan in irinotecan-refractory elderly patients with metastatic colorectal cancer.

BACKGROUND: We investigated the influence of comorbidity, Eastern Cooperative Oncology Group (ECOG) performance status and age on the efficacy and safety profile of cetuximab and irinotecan in elderly irinotecan-pretreated patients with mCRC. METHODS: 497 patients with mCRC were entered in the database of this non-interventional study (NIS). Comorbid conditions were recorded. RESULTS: A total of 247 and 250 patients aged <65 and >65 years, respectively, with a median age of 66 y were documented; 78% of the patients showed a reduced ECOG status. Grade III/IV toxicities occurred in 18% of patients without any difference between age groups although older patients had more comorbidities with a higher Charlson Comorbidity Index (CCI) (p = 0.002). Skin rash was strongly related to response (p = 0.006). Age, line of therapy, ECOG, gender and CCI had no influence on response. The objective response rates were similar: 38.1% for age <65 years versus 36.4% for age >65 years (p = 0.57). Progression-free survival (PFS) did not differ between patients 18-65 years (6.0 months) and patients >65 years (6.2 months; p = 0.99). Only PS had a negative impact on PFS (hazard ratio (HR): 0,499; 95% confidence interval (CI) 0.34-0.72; p=0.002), whereas the presence of skin toxicity (grade>1) influenced PFS and response rate (RR) positively (HR: 2.04; 95% CI, 1.6-2.6; p<0.001). CONCLUSIONS: Only PS and age had a negative influence on PFS irrespective of CCI or age. There were no significant differences in response rate and safety profile for elderly patients when treated with cetuximab and irinotecan. Comorbidities and age had no influence on efficacy or toxicity.

Cetuximab-based therapy in elderly comorbid patients with metastatic colorectal cancer.

BACKGROUND: Clinical trials under-represent patients (pts) >65 years. Non-interventional studies (NISs) help to evaluate therapies in daily practice. This NIS evaluates efficacy and safety of cetuximab in combination with chemotherapy in metastatic colorectal cancer (mCRC) pts aged >65 years vs ≤ 65 years. METHODS: A total of 657 pts were recruited into the NIS and analysed applying descriptive statistics and χ(2) or Fisher's exact test. RESULTS: A total of 309 and 305 pts aged ≤ 65 and >65 years, respectively, were documented; 80% showing a reduced ECOG status of 1-2 and 95% having received at least one palliative treatment. Cetuximab was combined with irinotecan according to approval status. Grade III/IV toxicities occurred in 20% of pts without any difference between age groups although the older pts had significantly more pre-existing comorbidities (P=0.001). A total of 64.2% of the pts developed skin rash, which was strongly related to response (P<0.0002) without any difference between age groups (P=0.34). The objective response rates were 37.9% for ages 18-65 years vs 35.4% for >65 years. Progression-free survival (PFS) did not differ between pts 18-65 years old (6.5 months) in comparison with pts >65 years (7.0 months). In a multivariate analysis only ECOG status had a negative impact on PFS (HR: 0,675; 95% Cl, 0.53-0.87; P=0.0019). CONCLUSION: This NIS reports one of the largest mCRC collectives >65 years and reduced performance status. Cetuximab has a similar efficacy and safety profile for pts aged ≤ 65 and >65 years.

Second-line chemotherapy with pemetrexed after gemcitabine failure in patients with advanced pancreatic cancer: a multicenter phase II trial.

BACKGROUND: A standard second-line chemotherapy regimen has yet to be defined for patients with gemcitabine (Gem)-refractory advanced pancreatic cancer (PC). PATIENTS AND METHODS: In this multicenter phase II trial, patients with unresectable or metastatic PC who had progressed on single-agent Gem or a Gem-containing regimen received pemetrexed 500 mg/m(2) as a 10-min infusion every 3 weeks until disease progression or occurrence of unacceptable toxicity. The primary end point was the 3-month survival rate. RESULTS: A total of 192 treatment cycles were given to 52 patients. The overall response rate was 3.8% (two partial responses); 10 patients (19.2%) experienced stable disease, nine of them for >12 weeks. At least one CA 19-9 reduction > or =50% occurred in 12 patients (23.1%). The 3-month survival rate was 75% (95% confidence interval 63.2% to 86.8%), the median time to tumor progression was 7 weeks (range 1-62 weeks) and the median overall survival time was 20 weeks (range 1-84 weeks). Grade 3/4 hematological toxic effects included (percent of patients): neutropenia (17.3%), thrombocytopenia (5.8%) and anemia (3.8%). The most frequent non-hematological toxic effects were diarrhea, nausea and stomatitis/pharyngitis (23.1% each). CONCLUSION: Pemetrexed is a safe treatment option with moderate activity in patients with advanced PC after failure of Gem.

Dalteparin for prevention of catheter-related complications in cancer patients with central venous catheters: final results of a double-blind, placebo-controlled phase III trial.

BACKGROUND: Cancer patients receiving chemotherapy experience thromboembolic complications associated with the use of long-term indwelling central venous catheters (CVCs). This prospective, double-blind, placebo-controlled, multicenter study evaluated whether prophylactic treatment with a low molecular weight heparin could prevent clinically relevant catheter-related thrombosis. PATIENTS AND METHODS: Patients with cancer undergoing chemotherapy for at least 12 weeks (n=439) were randomly assigned, in a 2:1 ratio, to receive either dalteparin (5000 IU) or placebo, by subcutaneous injection, once daily for 16 weeks. Patients underwent upper extremity evaluation with either venography or ultrasound at the time of a suspected catheter-related complication (CRC) or upon completion of study medication. The primary end point, as determined by a blinded adjudication committee, was the occurrence of a CRC, defined as the first occurrence of any one of the following: clinically relevant catheter-related thrombosis that was symptomatic or that required anticoagulant or fibrinolytic therapy; catheter-related clinically relevant pulmonary embolism; or catheter obstruction requiring catheter removal. RESULTS: There was no significant difference in the frequency of CRCs between the dalteparin arm (3.7%) and the placebo arm (3.4%; P=0.88), corresponding to a relative risk of 1.0883 (95% confidence interval 0.37-3.19). No difference in the time to CRC was observed between the two arms (P=0.83). There was no significant difference between the dalteparin and placebo groups in terms of major bleeding (1 versus 0) or overall safety. CONCLUSIONS: Dalteparin prophylaxis did not reduce the frequency of thromboembolic complications after CVC implantation in cancer patients. Dalteparin was demonstrated to be safe over 16 weeks of treatment in these patients.

High reliability and sensitivity of the BCR/ABL1 D-FISH test for the detection of BCR/ABL rearrangements.

The BCR/ABL1 fusion gene is mainly caused by the t(9; 22)(q34; q11.2) translocation, which results in the Philadelphia (Ph) chromosome. The Ph chromosome is the typical hallmark in chronic myeloid leukemia (CML), but can also be present in acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). The BCR/ABL1 rearrangement is an important tumor classification marker and a useful prognostic factor allowing an adequate therapy management. Ph chromosome detection by conventional cytogenetics (CC) can be hampered by low quantity and quality of metaphases from tumor cells. Furthermore, BCR/ABL1 rearrangements may be hidden due to cryptic rearrangements or complex aberrations. Therefore, molecular cytogenetic methods turned out to be useful tools for the detection of BCR/ABL1 rearrangements. We performed fluorescent in situ hybridization (FISH) with the recently developed BCR/ABL1 D-FISH probe (QBIOgene, Illkirch, F) on cultured bone marrow and peripheral blood cells of 71 patients with CML, ALL, AML, and myeloproliferative disorder (MPD). FISH results and the results of banding methods were directly compared. Based on the analyses of >200 nuclei per patient, D-FISH correlated closely with CC and allowed an accurate quantification of BCR/ABL1 rearrangements even in a low percentage of aberrant cells. No false-positive or false-negative results were obtained. Furthermore, the D-FISH probe detected three cryptic and one complex BCR/ABL1 rearrangement, which were not visible by CC. We conclude that D-FISH reliably detects standard Ph chromosomes as well as its variant translocations and accurately quantifies BCR/ABL1 rearrangements prior and during cancer treatment as well as in the phase of remission, in daily routine tumor cytogenetic diagnostics.

Combination chemotherapy with docetaxel and cisplatin for locally advanced and metastatic gastric cancer.

BACKGROUND: Poor treatment results obtained with palliative chemotherapy for advanced gastric cancer indicate the need for new effective and well-tolerated regimens. PATIENTS AND METHODS: Forty-three patients with locally advanced or metastatic gastric cancer were enrolled in a phase II study to evaluate the efficacy and safety of combination chemotherapy with doxetacel 75 mg/m2 and cisplatin 75 mg/m2 given every three weeks. RESULTS: Thirty-nine patients were evaluable for response. Four achieved a complete response and twelve a partial response, for an overall response rate of 37.2% (16 of 43 patients; 95% confidence interval (CI): 22.98-53.72). Median time to progression was 6.1 months and median overall survival 10.4 months. Forty-two percent of all patients were still alive at one year and twelve percent at two years. The major toxicity was leukopenia which reached grade 3-4 in 18.6% (n = 8) of the patients. However, no febrile neutropenia occurred. Non-haematological toxicities were usually mild to moderate. Grade 3 toxicities included diarrhea (9% of the patients), nausea and vomiting (7%), and alopecia (7%). Severe ototoxicity with or without peripheral neuropathy developed after completion of chemotherapy in two patients. CONCLUSIONS: These results suggest that the combination of docetaxel and cisplatin has moderate toxicity and is an effective regimen for the treatment of advanced gastric cancer, both with regard to response rate and survival.

Membrane-bound proteindisulfide isomerase (PDI) is involved in regulation of surface expression of thiols and drug sensitivity of B-CLL cells.

The proteindisulfide isomerase (PDI), a multifunctional cytoplasmic enzyme with additional chaperone activity, has been shown recently, using monoclonal antibodies, to be located on the membrane of mature human B lymphocytes and B cell chronic lymphocytic leukemia (B-CLL) cells. Here, evidence is presented that this antigen exhibits catalytic activity as measured by the reductive degradation of insulin (release of A chain molecules) on intact B cells in patients suffering from B-CLL, as well as on JVM 13 cells (B-CLL cell line). More than 98% of these cells exhibited PDI activity which could be inhibited by bacitracin and also by monoclonal and polyclonal antibodies to PDI. Interestingly, surface PDI expression was strongly correlated in our study with protein-bound membrane SH groups. These surface protein thiols were specifically determined by using low concentrations of the chloromethyl-derivative based fluorescent probe 5-(and6)-(((4-chloromethyl)-benzoyl)amino)-tetramethyl-rhodamine (CMTMR) at low temperature in the presence of sodium azide in flow cytometry. The highest PDI and SH expression was found on B lymphocytes, particularly B-CLL cells. The mean fluorescence intensity (MFI) of CMTMR-positive B cells in the B-CLL line was up to 10-fold higher than that of controls, indicating a strong elevation of cell membrane-located protein thiols on malignant B cells. The link between PDI and SH expression on cell surfaces points to a functional interaction between the two. Treatment with bacitracin resulted in a strong inhibition of PDI and a dramatic increase in surface protein thiol expression of B-CLL cells. Similar effects could be observed by cell treatment with anti-PDI antibodies, indicating that this enzyme system plays a crucial role in the regulation of protein-bound SH groups. Interestingly, artificially induced protein thiol expression led to significantly higher cellular resistance to the cytostatic drugs chlorambucil, vinblastin, and cisplatin in vitro as measured by cell growth. These data suggest for the first time a regulatory effect of PDI on the surface protein thiol status of B cells. The increased expression of PDI may play a crucial role in SH-mediated protection and drug resistance in malignant B lymphocytes.

Alterations in structure and cellular localization of molecular forms of DP IV/CD26 during T cell activation.

Dipeptidyl peptidase IV (DP IV, CD26), known as an activation marker of T lymphocytes, is a proline-specific protease thought to be involved in the regulation of the immune response. The physiological role of dipeptidyl peptidase IV in the immune system and the molecular events of lymphocyte activation mediated by this enzyme are only partly established. Former results suggested the occurrence of different molecular forms of DP IV in distinct human sources. As yet it has been unknown whether DP IV from human hematopoietic cells also appears in different forms and whether similar structural modifications are involved in functional processes of the regulation of the immune response. Here we describe that lymphocytic DP IV/CD26 occurs in various molecular forms and that some of them are associated with the activation process. In cell lysates of mitogen-activated lymphocytes at least 5 enzymatically active DP IV forms and up to 11 immunoreactive molecular forms of this enzyme with isoelectric points between pH 3.5 and 5.9 were discernible. Corresponding analyses of soluble and membrane cell fractions of human lymphocytes showed significant differences in the staining pattern of molecular DP IV structures. After mitogenic stimulation a special molecular form of DP IV arises in the membrane, which was originated either from the soluble part of the cell (translocation) or represents a new synthesized form. Particularly, changes of molecular DP IV forms after mitogenic stimulation strongly suggest that special forms/epitopes of this enzyme are directly involved in the process of lymphocyte activation and growth. Importantly, different monoclonal DP IV antibodies partly define different molecular forms of DP IV. Moreover, the pattern of immunostaining and enzymatic staining (Gly-Pro-beta-methoxynaphthylamide) also reveals drastic differences. These data strongly suggest a direct relationship between the expression/recognition of special DP IV epitopes and the contradictory functional effects of monoclonal DP IV antibodies found by us and other groups.

Expression and localization of messenger RNA for tumor necrosis factor receptor (TNF-R) I and TNF-RII in pregnant mouse uterus and placenta.

The temporal and cell-specific localization of tumor necrosis factor (TNF) receptor mRNAs in the uterus and placenta during pregnancy in the mouse was investigated. Messenger RNA for TNF and the TNF receptors (TNF-RI, p55/p60 and TNF-RII, p75/p80) was assessed by northern blot andin situ hybridization. TNF, TNF-RI and TNF-RII specific transcripts were present on days 7 through 18 of pregnancy. Relative concentrations of TNF mRNA decreased from days 7 to 18 with levels being higher in the uterus than the placenta. In contrast TNF-RI mRNA levels were constant throughout gestation and no differences were seen between steady state levels in the uterus and placenta. Two transcripts for TNF-RII (3.6 and 4.5 kb) were identified in all tissues. Steady state levels of TNF-RII mRNA increased throughout gestation and levels were higher in the placenta than in the uterus. On day 9 of gestation, TNF-RI and TNF-RII mRNAs were localized to undecidualized endometrium, mesometrial decidual cells, and the developing placenta. In addition, muscle cells contained TNF-RI but not TNF-RII mRNA. By day 15 of gestation, TNF-RI and TNF-RII transcripts were primarily localized to the uterine epithelium and trophoblast giant cells and spongiotrophoblast cells in the placenta. The results of these studies reveal the uterine and placental cell-specific expression of TNF receptor mRNAs during pregnancy in the mouse and provide insight into the cellular targets of TNF action.

Thiol-proteindisulfide-oxidoreductase (proteindisulfide isomerase): a new plasma membrane constituent of mature human B lymphocytes.

The thiol-proteindisulfide-oxidoreductase (TPO, EC 1.8.4.2., proteindisulfide isomerase, EC 5.3.4.1.) is known as an cytoplasmatic enzyme, and is thought to be involved in the post-translational folding of disulfide containing proteins. Using monoclonal and polyclonal antibodies the authors were able to prove that this enzyme or an unknown homologous protein is localized also to the plasma membrane of B lymphocytes. In peripheral blood from healthy donors 11% of the mononuclear cells (PBMNC) expressed this surface antigen whereas in PBMNC of patients with B-cell chronic lymphocytic leukaemia 76% of the MNC were positive. This value correlates well with the known B-cell markers CD19 and CD20. However, this antigen is different from all known clustered B-cell markers. Immunoprecipitation analysis of PHA-stimulated PBMNC and of cells from patients suffering from chronic lymphocytic leukaemia revealed a membrane protein with the same molecular weight (61 kDa) as the TPO. These data suggest that this enzyme is present not only in the cytoplasm but also on the surface of B cells and that it is possibly involved in the regulation of the SH-SS status of the cell membrane proteins of B lymphocytes.

Induction of protein disulphide-isomerase and immunoglobulins by pokeweed mitogen in human lymphocytes.

The Protein disulphide-isomerase (PDI, EC 5.3.4.1, Thiol-proteindisulphide oxidoreductase, EC 1.8.4.2) is thought to regulate the sulfhydryl status of cells and to catalyze thiol/disulphide exchange reactions involved in the post-translational processing of disulphide containing secretory proteins. The aim of the present investigations was to study the possible function of this enzyme in differentiation of B lymphocytes and immunoglobulin synthesis. Non-adherent human mononuclear cells or purified T cells were cultured in presence and absence of Pokeweed mitogen over 3, 5 and 7 days. Monoclonal antibodies and a rabbit polyclonal antiserum specific for human liver PDI were produced to determine the concentration of PDI by an ELISA technique and cytoplasmic immunofluorescence. After PWM stimulation, both, the cellular content of PDI as well as that of immunoglobulin, particularly IgM, have been found to be induced in a time dependent manner with a 2-3 fold increase in comparison to unstimulated cells. The specific induction of PDI in human B lymphocytes was also confirmed in Western blotting. Our findings suggest that PDI plays a critical role in the final stages of B cell differentiation and immunoglobulin synthesis by activated B cells and plasma cells, respectively.

[Immunochemical determination of human thiol protein disulfide oxidoreductase in cell and tissue homogenates by competitive EIA]. / Immunochemische Bestimmung der humanen Thiol-Proteindisulfid-Oxidoreduktase in Zell- und Gewebshomogenaten mit Hilfe eines kompetitiven EIA.

Different monospecific antisera against thiol-protein disulfide oxidoreductase (TPO, EC 1.8.4.2, protein-disulfide isomerase, EC 5.3.4.1) were raised in rabbits by immunization with purified human TPO and characterized by means of Laurell and immunoblot techniques. A competitive anti-TPO-EIA with insolubilized TPO has been used to determine this enzyme in cells and tissue homogenates. The assay shows a sensitivity of 1.2 ng/ml and a specificity of about 99%. The TPO content in relation to the total protein was found to be: in pancreas 0.65%, liver 0.45%, spleen 0.12%, placenta 0.16%, tonsils 0.06% and lymph nodes 0.03%.