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Background: Mutations in the KRAS gene can be detected in about 70-90% of pancreatic cancer (PC) cases. Whether these mutations have a prognostic or predictive value remains elusive. Furthermore, the clinical relevance of the extended RAS (KRAS+NRAS) mutational status is unclear in PC., Methods: We prospectively defined a PC patient population who received erlotinib-free chemotherapy regimens. A statistically significant difference between KRAS wild-type and KRAS mutated tumours in at least 160 patients in this population would support the assumption of a rather prognostic role of KRAS., Results: One hundred and seventy-eight tumour samples were collected from prospective clinical studies and successfully analysed for the extended RAS status: 37 tumours were KRAS wild-type (21%), whereas 141 (79%) carried a KRAS mutation; 132 of these mutations were found in KRAS exon 2 (74%), whereas only 9 mutations (5%) were detected in KRAS exon 3. Within KRAS exon 4 and NRAS exons 2-4, no mutations were apparent. There was no significant difference in overall survival for KRAS wild-type vs mutant patients (9.9 vs 8.3 months, P=0.70)., Conclusions: Together with the results of the AIO-PK-0104-trial, the present analysis supports the notion that KRAS mutation status is rather predictive than prognostic in advanced PC.

Background: Conflicting results on the role of secreted protein acidic and rich in cysteins (SPARC) expression have been reported in resected pancreatic ductal adenocarcinoma (PDAC), and its prognostic and/or predictive role in advanced PDAC (aPDAC) has not been extensively investigated yet. This study was designed to evaluate SPARC expression as a biomarker in aPDAC patients (pts) not receiving nab-paclitaxel., Methods: Using immunohistochemistry, we examined the stromal as well as the tumoral (i.e., cytoplasmic) SPARC expression in tumour tissue (primary tumours and metastases) of 134 aPDAC pts participating in completed prospective clinical and biomarker trials. The SPARC expression levels were correlated to the pts' clinicopathological parameters and survival times., Results: Sixty-seven per cent of the analysed tumours showed high stromal SPARC expression, which was not associated with overall survival (OS, median 9.1 vs 7.6 months, P=0.316). A positive cytoplasmic SPARC expression was detected in 55% of the tumours and correlated significantly with inferior progression-free survival (PFS, 6.2 vs 8.6 months, P=0.004) and OS (7.8 vs 8.4 months, P=0.032). This association was strongest for pts, where primary tumour tissue was examined (PFS: 6.7 vs 10.8 months, P=0.004; OS: 7.9 vs 11.9 months, P=0.030), whereas no significant correlation was detected for pts, where only metastatic tissue was available (PFS: 5.8 vs 6.6 months, P=0.502; OS: 7.0 vs 7.8 months, P=0.452). In pts receiving gemcitabine-based chemotherapy cytoplasmic SPARC expression was significantly associated with an inferior PFS and OS (PFS: 6.2 vs 9.2 months, P=0.002; OS 7.3 vs 9.9 months, P=0.012), whereas no such association was detected for stromal SPARC expression or for pts receiving fluoropyrimidine-based chemotherapy., Conclusion: We identified cytoplasmic SPARC expression in the primary tumour as a biomarker associated with inferior PFS and OS in aPDAC. Cytoplasmic SPARC expression may furthermore act as a negative predictive biomarker in pts treated with gemcitabine-based chemotherapy.

Background: Drug-induced skin toxicity may correlate with treatment efficacy in cancer patients receiving chemotherapy or biological agents. The correlation of the capecitabine-associated hand-foot skin reaction (HFS) on outcome parameters in pancreatic cancer (PC) has not yet been investigated., Methods: Within the multicentre phase III AIO-PK0104 trial, patients with confirmed advanced PC were randomly assigned to first-line treatment with either capecitabine plus erlotinib (150 mg/day, arm A) or gemcitabine plus erlotinib (150 mg/day, arm B). A cross-over to either gemcitabine (arm A) or capecitabine (arm B) was performed after failure of the first-line regimen. Data on skin toxicity were correlated with efficacy study endpoints using uni- and multivariate analyses. To control for guarantee-time bias (GTB), we focused on subgroup analyses of patients who had completed two and three or more treatment cycles., Results: Of 281 randomised patients, skin toxicity data were available for 255 patients. Median time to capecitabine-attributed HFS was two cycles, 36 of 47 (77%) HFS events had been observed by the end of treatment cycle three. Considering HFS during first-line treatment in 101 patients treated with capecitabine for at least two cycles within the capecitabine plus erlotinib arm, time to treatment failure after first- and second-line therapy (TTF2) and overall survival (OS) both were significantly prolonged for the 44 patients (44%) with HFS compared to 57 patients without HFS (56%) (TTF2: 7.8 vs. 3.8 months, HR 0.50, p = 0.001; OS: 10.4 vs. 5.9 months, HR 0.55, p = 0.005). A subgroup analysis of 70 patients on treatment with capecitabine for at least three cycles showed similar results (TTF2: 8.3 vs. 4.4 months, HR 0.53, p = 0.010; OS: 10.4 vs. 6.7 months, HR 0.62, p = 0.056)., Conclusion: The present subgroup analysis from AIO-PK0104 suggests that HFS may serve as an independent clinical predictor for treatment outcome in capecitabine-treated patients with advanced PC.

The objective of this study was to assess the efficacy and tolerability of YM155, a survivin suppressor, in combination with docetaxel, compared with docetaxel alone in patients with HER2-negative metastatic breast cancer. This phase II, multicenter, open-label, 2-arm study randomized patients (≥18 years) with histologically or cytologically confirmed stage IV HER2-negative metastatic breast cancer and ≥1 measurable lesion, to receive docetaxel alone or docetaxel plus YM155. The primary endpoint was progression-free survival (PFS). Secondary endpoints included objective response rate (ORR), overall survival (OS), duration of response (DOR), clinical benefit rate (CBR), time to response (TTR), biomarker assessment, and analysis of circulating tumor cells. Patients were women diagnosed with HER2-negative breast cancer; most had received prior drug therapies. The median PFS was 8.4 months with YM155 plus docetaxel (n = 50) and 10.5 months with docetaxel alone (n = 51; HR 1.53; 95 % CI 0.83, 2.83; P = 0.176). No statistically significant differences were observed for secondary endpoints, although slightly greater OS (630 vs 601 days; P = 0.768), CBR (84.3 vs 82.0 %; P = 0.855), DOR, and TTR were observed with docetaxel alone compared with YM155 plus docetaxel, whereas ORR was similar (25.5 vs 26.0). The most common TEAEs observed with YM155 plus docetaxel compared with docetaxel alone were neutropenia (83.3 vs 84.3 %), alopecia (62.5 vs 52.9 %), fatigue (50 vs 41.2 %), and nausea (37.5 vs 41.2 %). Although YM155 is a novel drug that suppresses survivin, YM155 plus docetaxel exhibited no statistically significant differences in endpoints compared with docetaxel alone. The combination regimen was well tolerated.

Background: The role of pERK, pAKT and p53 as biomarkers in patients with advanced pancreatic cancer has not yet been defined., Methods: Within the phase III study AIO-PK0104 281 patients with advanced pancreatic cancer received an erlotinib-based 1st-line regimen. Archival tissue from 153 patients was available for central immunohistochemistry staining for pERK, pAKT and p53. Within a subgroup analysis, biomarker data were correlated with efficacy endpoints and skin rash using a Cox regression model., Results: Fifty-five out of 153 patients were classified as pERKlow and 98 patients as pERKhigh; median overall survival (OS) was 6.2 months and 5.7 months, respectively (HR 1.29, p = 0.16). When analysing pERK as continuous variable, the pERK score was significantly associated with OS (HR 1.06, 95% CI 1.0-1.12, p = 0.05). Twenty-one of 35 patients were pAKTlow and 14/35 pAKThigh with a corresponding median OS of 6.4 months and 6.8 months, respectively (HR 1.03, p = 0.93). Four out of 50 patients had a complete loss of p53 expression, 20 patients a regular expression and 26 patients had tumors with p53 overexpression. The p53 status had no impact on OS (p = 0.91); however, a significant improvement in progression-free survival (PFS) (6.0 vs 1.8 months, HR 0.24, p = 0.02) and a higher rate of skin rash (84% vs 25%, p = 0.02) was observed for patients with a regular p53 expression compared to patients with a complete loss of p53., Conclusion: pERK expression may have an impact on OS in erlotinib-treated patients with advanced pancreatic cancer; p53 should be further investigated for its potential role as a predictive marker for PFS and skin rash., Trial Registration: NCT00440167 (registration date: February 22, 2007).

Objective: AIO-PK0104 investigated two treatment strategies in advanced pancreatic cancer (PC): a reference sequence of gemcitabine/erlotinib followed by 2nd-line capecitabine was compared with a reverse experimental sequence of capecitabine/erlotinib followed by gemcitabine., Methods: 281 patients with PC were randomly assigned to 1st-line treatment with either gemcitabine plus erlotinib or capecitabine plus erlotinib. In case of treatment failure (eg, disease progression or toxicity), patients were allocated to 2nd-line treatment with the comparator cytostatic drug without erlotinib. The primary study endpoint was time to treatment failure (TTF) after 1st- and 2nd-line therapy (TTF2; non-inferiority design). KRAS exon 2 mutations were analysed in archival tumour tissue from 173 of the randomised patients., Results: Of the 274 eligible patients, 43 had locally advanced and 231 had metastatic disease; 140 (51%) received 2nd-line chemotherapy. Median TTF2 was estimated with 4.2 months in both arms; median overall survival was 6.2 months with gemcitabine/erlotinib followed by capecitabine and 6.9 months with capecitabine/erlotinib followed by gemcitabine, respectively (HR 1.02, p=0.90). TTF for 1st-line therapy (TTF1) was significantly prolonged with gemcitabine/erlotinib compared to capecitabine/erlotinib (3.2 vs 2.2 months; HR 0.69, p=0.0034). Skin rash was associated with both TTF2 (rash grade 0/1/2-4:2.9/4.3/6.7 months, p<0.0001) and survival (3.4/7.0/9.6 months, p<0.0001). Each arm showed a safe and manageable toxicity profile during 1st- and 2nd-line therapy. A KRAS wild-type status (52/173 patients, 30%) was associated with an improved overall survival (HR 1.68, p=0.005)., Conclusion: Both treatment strategies are feasible and demonstrated comparable efficacy; KRAS may serve as biomarker in patients with advanced PC treated with erlotinib.

Background: We aimed to identify molecular epidermal growth factor receptor (EGFR) tissue biomarkers in pancreatic cancer (PC) patients treated with the anti-EGFR agent erlotinib within the phase 3 randomised AIO-PK0104 study., Methods: AIO-PK0104 was a multicenter trial comparing gemcitabine/erlotinib followed by capecitabine with capecitabine/erlotinib followed by gemcitabine in advanced PC; primary study end point was the time-to-treatment failure after first- and second-line therapy (TTF2). Translational analyses were performed for KRAS exon 2 mutations, EGFR expression, PTEN expression, the EGFR intron 1 and exon 13 R497K polymorphism (PM). Biomarker data were correlated with TTF, overall survival (OS) and skin rash., Results: Archival tumour tissue was available from 208 (74%) of the randomised patients. The KRAS mutations were found in 70% (121 out of 173) of patients and exclusively occurred in codon 12. The EGFR overexpression was detected in 89 out of 181 patients (49%) by immunohistochemistry (IHC), and 77 out of 166 patients (46%) had an EGFR gene amplification by fluorescence in-situ hybridisation (FISH); 30 out of 171 patients (18%) had a loss of PTEN expression, which was associated with an inferior TTF1 (first-line therapy; HR 0.61, P=0.02) and TTF2 (HR 0.66, P=0.04). The KRAS wild-type status was associated with improved OS (HR 1.68, P=0.005); no significant OS correlation was found for EGFR-IHC (HR 0.96), EGFR-FISH (HR 1.22), PTEN-IHC (HR 0.77), intron 1 (HR 0.91) or exon 13 R497K PM (HR 0.83). None of the six biomarkers correlated with the occurrence of skin rash., Conclusion: The KRAS wild-type was associated with an improved OS in erlotinib-treated PC patients in this phase 3 study; it remains to be defined whether this association is prognostic or predictive.

Adjacent ductal carcinoma in situ (DCIS) is found in approximately 45% of invasive ductal carcinomas (IDC) of the breast. Pure DCIS overexpresses HER2 in approximately 45%. There is uncertainty whether adjacent DCIS impacts on the response to neoadjuvant chemotherapy and trastuzumab as well as whether HER2 expression in IDC component or adjacent DCIS changes throughout treatment. Core biopsies and surgical tissue from participants of the GeparQuattro study with HER2-positive IDC were centrally examined for the area of invasive ductal component and adjacent DCIS before and after receiving neoadjuvant anthracycline-taxane-trastuzumab containing chemotherapy. HER2 overexpression in IDC and adjacent DCIS was quantified separately by immunohistochemistry using the Ventana automated staining system. Pathological complete response (pCR) was defined as no residual invasive or non-invasive tumor tissue. Fifty-nine (37.3%) of 158 IDCs presented with adjacent DCIS at diagnosis. These tumors showed lower regression grades than pure IDC (P = 0.033). The presence of adjacent DCIS was an independent negative predictor of pCR [odds ratio 0.42 (95% CI 0.2-0.9), P = 0.027]. Adjacent DCIS area decreased from pre-treatment to surgery (r = 0.205) with 30 (50.8%) IDCs with adjacent DCIS showing complete eradication of adjacent DCIS. HER2 status of adjacent DCIS was highly correlated with HER2 status of IDC component before (r = 0.892) and after treatment (r = 0.676). Degree of HER2 overexpression of the IDC component decreased in 16 (33.3%) out of 49 patients without a pCR. These 16 IDCs showed lower RGs compared to the 33 IDCs with unchanged HER2 expression (P = 0.055). HER2-positive IDCs with adjacent DCIS is less responsive to neoadjuvant chemotherapy and trastuzumab compared to pure IDC. However, complete eradication of adjacent DCIS is frequently observed. HER2-overexpression of the invasive ductal component decreases in a subset of tumors, which showed less tumor regression.

To date, only limited toxicity data are available for the combination of erlotinib with either capecitabine or gemcitabine as front-line therapy for advanced pancreatic cancer. Within a randomized phase III trial, 281 treatment-naive patients were randomly assigned between capecitabine (2000 mg/m/day, for 14 days, once every 3 weeks) plus erlotinib (150 mg/day, arm A) and gemcitabine (1000 mg/m as a 30-min infusion) plus erlotinib (150 mg/day, arm B). In case of treatment failure, patients were crossed over to a second-line treatment with the comparator cytostatic drug without erlotinib. The primary study endpoint was the time to treatment failure of second-line therapy (TTF2). This interim analysis of toxicity contains safety data from the first 127 randomized patients. During first-line therapy, patients received a median number of three treatment cycles (range 0-13) in both the arms. Regarding chemotherapy, a treatment delay was observed in 12% of the cycles in arm A and in 22% of the cycles in arm B. Dose reductions of the cytostatic drug were performed in 18 and 27% of treatment cycles, respectively. Erlotinib dose reductions were performed in 6 and 11% of all cycles. Grade 3/4 hematological toxicity was <10% in both the arms; major grade 3/4 toxicities in arms A and B were diarrhea (9 vs. 7%), skin rash (4 vs. 12%), and hand-foot syndrome (7 vs. 0%). No treatment-related death was observed. In conclusion, this interim safety analysis suggests that treatment with erlotinib 150 mg/day is feasible in combination with capecitabine or gemcitabine.

Background: The combination of docetaxel (Taxotere), cisplatin, and fluorouracil improved efficacy in gastric cancer, but was associated with substantial toxicity. This study was designed to incorporate docetaxel into a tolerable biweekly (once every 2 weeks) oxaliplatin-based chemotherapy regimen., Patients and Methods: Patients with measurable, metastatic adenocarcinoma of the stomach or esophagogastric junction and no prior chemotherapy received oxaliplatin 85 mg/m(2), leucovorin 200 mg/m(2), and fluorouracil 2600 mg/m(2) as a 24-h infusion in combination with docetaxel 50 mg/m(2) (FLOT) on day 1 every 2 weeks. Prophylactic growth factors were not administered., Results: Fifty-nine patients were enrolled; 54 received treatment. Patients had a median age of 60 years (range 29-76) and most (93%) of them had metastatic disease. Objective responses were observed in 57.7% of patients with a median time to treatment response of 1.54 months. Median progression-free survival (PFS) and overall survival were 5.2 and 11.1 months, respectively. Twenty-five percent of patients experienced prolonged (>12 months) PFS. Frequent (>10%) grade 3 or 4 toxic effects included neutropenia in 26 (48.1%), leukopenia in 15 (27.8%), diarrhea in 8 (14.8%), and fatigue in 6 (11.1%) patients. Complicated neutropenia was observed in two (3.8%) patients, only., Conclusions: Biweekly FLOT is active and has a favorable safety profile.

Advanced biliary tract carcinomas (BTCs) are often diagnosed at an advanced/metastatic stage and have a poor prognosis. The combination of gemcitabine and oxaliplatin (GEMOX) has shown promising activity in this setting. This international phase II study evaluated the efficacy and safety of GEMOX as first-line therapy in patients with advanced BTCs. Eligible patients with previously untreated locally advanced or metastatic BTC received gemcitabine 1000 mg m(-2) (day 1) and oxaliplatin 100 mg m-2 (day 2), every 2 weeks. Seventy patients were enroled; 72.9% had metastatic disease. Sixty-seven patients were treated. There were 10 confirmed partial responses (14.9%; 95% confidence interval (CI), 7.4-25.7%) in the treated population (RECIST). Twenty-four patients (35.8%) had stable disease. The objective response rate was 20.5% in patients with non-gallbladder cancers (9/44 patients) and 4.3% in patients with gallbladder cancers (1/23). Median overall survival for the intent-to-treat population was 8.8 months (95% CI, 6.9-11.1%) and progression-free survival was 3.4 months (95% CI, 2.5-4.6%). Grade 3/4 toxicities included thrombocytopenia (14.9% of patients), alanine aminotransferase elevation (13.4%), anaemia (10.4%), neutropenia (11.9%) and pain (1 1.9%). In this study, GEMOX demonstrated activity in non-gallbladder carcinoma, but poor activity in gallbladder carcinoma. GEMOX is well tolerated in advanced BTCs.

Background: We evaluated the efficacy of a single fixed 6 mg dose of pegfilgrastim (a pegylated version of filgrastim) per cycle of chemotherapy, compared with daily administration of filgrastim, in the provision of neutrophil support., Patients and Methods: Patients (n = 157) were randomized to receive either a single 6 mg subcutaneous (s.c.) injection of pegfilgrastim or daily 5 mg/kg s.c. injections of filgrastim, after doxorubicin and docetaxel chemotherapy (60 mg/m(2) and 75 mg/m(2), respectively). Duration of grade 4 neutropenia, depth of neutrophil nadir, incidence of febrile neutropenia, time to neutrophil recovery and safety information were recorded., Results: A single 6 mg injection of pegfilgrastim was as effective as daily injections of filgrastim for all efficacy measures for all cycles. The mean duration of grade 4 neutropenia in cycle 1 was 1.8 and 1.6 days for the pegfilgrastim and filgrastim groups, respectively. Results for all efficacy end points in cycles 2-4 were consistent with the results from cycle 1. A trend towards a lower incidence of febrile neutropenia was noted across all cycles with pegfilgrastim compared with filgrastim (13% versus 20%, respectively). A single fixed dose of pegfilgrastim was as safe and well tolerated as standard daily filgrastim., Conclusions: A single fixed dose of pegfilgrastim administered once per cycle of chemotherapy was comparable to multiple daily injections of filgrastim in safely providing neutrophil support during myelosuppressive chemotherapy. Pegfilgrastim may have utility in other clinical settings of neutropenia.

The pathogenesis of hypercalcemia of malignancy comprises increased net bone resorption and enhanced renal tubular reabsorption of calcium (Ca). To evaluate the prevalence of an increased renal tubular reabsorption of Ca index [tubular reabsorption of calcium index (TRCaI)] in cancer patients with hypercalcemia and of elevated circulating levels of PTH-related protein (PTHrP), which is recognized as a major mediator of this syndrome, we investigated 315 well rehydrated patients, aged 58.1 +/- 0.7 yr (mean +/- SEM), with hypercalcemia [albumin-corrected plasma Ca (pCa), >2.7 mmol/L] secondary to histologically proven malignancy. Changes in pCa and, therefore, various Ca filtered loads were obtained by different degrees of bone resorption inhibition achieved with a single infusion of the bisphosphonate ibandronate, given at various doses on a randomized, double blind basis. PTHrP was determined at baseline in 147 of the patients and 7 days after bisphosphonate therapy in 73. Before ibandronate therapy, pCa was 3.36 +/- 0.02 mmol/L, mean TRCaI was increased at 3.09 +/- 0.03 mmol/L glomerular filtration rate (GFR; normal, 2.40-2.90), and 65% of patients had TRCaI above 2.90 mmol/L GFR. Mean serum PTHrP levels were 4.9 +/- 0.5 pmol/L (normal, <2.5) and values above the normal range were found in 53% of the patients (76% in lung and upper respiratory tract malignancies). By 7 days after the infusion of ibandronate, a decrease in pCa of 0.69 +/- 0.03 mmol/L (20.0 +/- 0.7%; P < 0.001) and in bone resorption [mean change in fasting urinary Ca, 0.09 +/- 0.04 mmol/L GFR (47.6 +/- 8.6%; P < 0.001) and 14.4 +/- 1.7 nmol/mmol (27.6 +/- 10.6%; P < 0.01) in deoxypyridinoline] was observed. TRCaI was slightly lowered by 0.30 +/- 0.09 mmol/L GFR. Mean changes in PTHrP, 1,25-dihydroxyvitamin D3, and PTH were +0.7 +/- 0.4 (P = NS), +27.6 +/- 3.0 (P < 0.001), and +2.9 +/- 0.8 (P < 0.005) pmol/L, respectively. After ibandronate treatment, the relative risk of relapsing hypercalcemia was particularly increased (3.43-fold) in lung and upper respiratory tract malignancies. These results obtained in a large cohort of patients indicate a significant prevalence of an increased renal tubular reabsorption of calcium index in hypercalcemia of malignancy and a substantial proportion of patients with detectable PTHrP.

Vegetables, fruits, and whole grains contain a wide variety of phytochemicals that have the potential to modulate cancer development. There are many biologically plausible reasons why consumption of plant foods might slow or prevent the appearance of cancer. These include the presence in plant foods of such potentially anticarcinogenic substances as carotenoids, chlorophyll, flavonoids, indole, isothiocyanate, polyphenolic compounds, protease inhibitors, sulfides, and terpens. The specific mechanisms of action of most phytochemicals in cancer prevention are not yet clear but appear to be varied. Considering the large number and variety of dietary phytochemicals, their interactive effects on cancer risk may be extremely difficult to assess. Phytochemicals can inhibit carcinogenesis by inhibiting phase I enzymes, and induction of phase II enzymes, scavenge DNA reactive agents, suppress the abnormal proliferation of early, preneoplastic lesions, and inhibit certain properties of the cancer cell.

In order to replace the central venous line necessary for continuous infusion of vincristine and doxorubicin with high-dose dexamethasone (VAD) and to avoid hospitalization, we evaluated the efficacy and toxicity of oral idarubicin, vincristine and dexamethasone (VID) in patients with multiple myeloma. Vincristine (1.6 mg/m2, max 2 mg) was given as a bolus injection on day 1. Idarubicin was given in capsules 10 mg/m2/day for days 1-4 with an intraindividual dose escalation, 40 mg dexamethasone were given on days 1-4, 9-12, 17-20. Treatment cycles were repeated every 28 days. At this interim analysis, 53 patients have been entered into the ongoing trial; 46 patients are evaluable for toxicity. The median age was 60 years (interquartile range, 52-65). 46% were primary or secondary refractory, 20% had previously been treated with VAD and 30% had previously untreated disease, 4% had two or more relapses. Four patients died within 2 months from entry and were considered as early deaths (8.7%). 45% of the 42 patients evaluable for efficacy achieved a partial remission and 26% a minor remission. The median reduction of the M-component was 43% (interquartile range, 25-64%). VID is an effective and convenient alternative to VAD even in relapsed or refractory patients.

The current phase II study evaluates the safety and efficacy of paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) and 5-fluorouracil (5-FU) plus folinic acid in patients with advanced gastric cancer. Paclitaxel 175 mg/m2 was given intravenously over 3 hours on days 1 and 22; folinic acid 500 mg/m2 given intravenously over 2 hours followed by 5-FU 2,000 mg/m2 given intravenously over 24 hours was administered on days 1, 8, 15, 22, 29, and 36. Six weeks of treatment were considered one cycle, and each cycle was followed by 2 weeks off treatment. Twenty-two patients (six women and 16 men) with advanced/metastatic gastric cancer were entered on trial. All patients are evaluable for response and toxicity. None had received prior chemotherapy. Radiologically metastatic sites included gastric lymph nodes (64%), liver (36%), lungs (18%), peritoneum (18%), bone (9%), and skin (5%). No complete responses were observed. Seven patients (32%; 95% confidence interval, 12% to 52%) had a partial response. Sites of partial responses included the lungs, skin, lymph nodes, and locally advanced tumor. Twelve patients (55%) had stable disease and three (14%) had disease progression. At a median follow-up of 12 months (range, 1 to 17+ months), the median overall survival for all patients was 11 months (range, 1 to 17+ months; 95% confidence interval, 6.8 to 18.2) and the median progression-free interval was 8 months (range, 1 to 13+ months; 95% confidence interval, 4.7 to 9.8). Severe nonhematologic toxicities were alopecia (45%), fever/infection (9%), diarrhea (5%), and nausea/vomiting (5%). Grade 3/4 neutropenia occurred in three patients (14%). In summary, paclitaxel given every 3 weeks in combination with once-weekly, 24-hour continuous infusions of 5-FU/folinic acid is active in advanced gastric cancer and appears to achieve response rates comparable to regimens like etoposide/folinic acid/5-FU or 5-FU/doxorubicin/methotrexate. The toxicity of this new combination is moderate and allows treatment in an outpatient setting. Ongoing studies are evaluating the activity of paclitaxel combined with weekly continuous infusions of 5-FU/folinic acid with or without cisplatin.

Retinoids can inhibit cell growth and induce cell differentiation in experimental tumour models. Human alcohol dehydrogenase (ADH) exists as a group of enzymes that can be placed into five classes based upon structural and functional distinctions. Human class I ADH catalyses the oxidation of a wide variety of alcohols including ethanol and retinol, whereas human class II ADH does not catalyse the oxidation of retinol. Using specific fluorescent substrates, class I and class II ADH activity in human sera was determined. No significant changes in class I or II activity were observed after 4 weeks of treatment with cis-retinoic acid (cRA). While total ADH activity was increased from 84 +/- 78 mU/1 to 206 +/- 70 mU/1 (mean +/- SD, P < 0.02) after 1 week of treatment, there were no further significant changes after 4 weeks of treatment with cRA. Sex-related differences were observed on total ADH activity after 1 week of treatment with cRA. Although total ADH activity of patients with cancer of the cervix increased significantly after 1 week of treatment, there were no significant changes in total activity in head and neck cancer patients. This sex-related difference might be dependent on the stage of the menstrual cycle. The elimination of ethanol in women can be either faster or slower than in men depending on the stage of menstrual cycle. This study therefore suggests that the main ADH activity observed in serum belongs to class II, and not to class I ADH. The data from this study also suggest that retinoic acid has a positive feedback effect on total ADH activity after 1 week of treatment.

Conditioning therapy preceding bone marrow transplantation (BMT) usually consists of high-dose chemotherapy and total body irradiation (TBI). It has acute and delayed toxic effects on several tissues, possibly related to peroxidation processes and exhaustion of antioxidants. Early studies indicated an increase of peroxide processes and a decrease of antioxidants during conditioning therapy. Hence, we investigated the effect of antioxidant supplementation on peroxidation processes and antioxidant status. We supplemented a patient group (N = 16) [BMT (+)], with oral 45 mg beta-carotene, 825 mg alpha-tocopherol and 450 mg ascorbic acid daily for three weeks before conditioning therapy. Another patient group (N = 10), BMT(-), was not supplemented with antioxidants before conditioning therapy. In order to investigate the physiologic effect of supplement antioxidants a healthy control group (N = 10) was supplemented with the same doses as BMT(+). Peroxide concentrations in plasma were measured by using the cholesterol oxidase (CHOD)-iodide method and antioxidants were measured by HPLC. Before supplementation the beta-carotene and alpha-tocopherol concentrations were comparable in both patient groups. After supplementation significantly higher beta-carotene and alpha-tocopherol concentrations were measured in the supplemented patients, BMT(+), than in the unsupplemented patients, BMT(-). After conditioning therapy, BMT(+) patients showed a significantly higher beta-carotene concentration (p < 0.05) than before supplementation. In BMT(-) patients the beta-carotene (p < 0.05) and alpha-tocopherol concentrations (p < 0.01) decreased significantly and the lipid peroxide concentration increased significantly following conditioning therapy. We conclude that antioxidant supplementation prior to conditioning therapy reduces peroxidation processes induced by conditioning therapy in bone marrow recipients.

A phase II trial was performed to evaluate the efficacy and toxicity of the combination of paclitaxel and 5-fluorouracil (5-FU)/folinic acid in patients with advanced gastric carcinoma. Twenty-two patients (six female and 16 male) with advanced or metastatic disease were enrolled. None of them had received prior chemotherapy. Paclitaxel was administrated as a 3 h infusion of 175 mg/m2 at days 1 and 22, 5-FU 2000 mg/m2 i.v. over 24 h and folinic acid 500 mg/m2 i.v. 2 h prior to 5-FU weekly from days 1 to 36. Seven patients (32%) had partial remissions including the lungs, skin, lymph nodes and locally advanced primary tumor. The median overall survival was 11 months (range 1-17+) and the median progression-free interval was 8 months (range 1-13+). Neutropenia (WHO grade III/IV) occurred in 14% of patients. Other main toxicities were alopecia in 45%, fever/infection in 9%, and nausea/vomiting and diarrhea in 5%. In conclusion, the combination of paclitaxel and continuously infused 5-FU/folinic acid appears to be an active regimen for advanced gastric carcinoma with a remission rate comparable to ELF or FAMtx. The moderate toxicity allows treatment on an outpatient basis.

The objective of this study was to investigate the effect of alcohol administration on jejunoileal bypass (JIB)-induced liver dysfunction in rats resulting in abnormalities of fatty acid composition of cell membranes, and whether methionine is able to reverse these changes. Male Wistar rats were subjected to a jejunoileal bypass operation. For 12 weeks, all groups were pair-fed either an alcohol-containing (36% of total calories) liquid diet or a liquid diet in which alcohol was replaced isocalorically by starch. Methionine supplementation in three control groups was 0, 32, 160 and 224 mg/kg body weight/day and the rats in the four alcohol feeding groups received 0, 32, 160 and 224 mg/kg body weight/day. In the alcohol group without any methionine supplementation, higher proportions of oleic and linoleic acid and lower proportions of docosahexaenoic and arachidonic acid became evident in tissue samples of liver and jejunum, in comparison with the other alcohol group. A possible explanation for this reduction in tissue polyunsaturated fatty acid (PUFA) may be a decrease in the activities of delta 6-and delta 5-desaturases, and subsequently a displacement of PUFA from lipid fractions by other fatty acids. Interestingly, in the alcohol group with the highest methionine supplementation, compared to all other alcohol groups, lower proportions of oleic acid and higher proportions of docosahexaenoic acid, appeared. A possible explanation for this increase of PUFA in tissue may be increased activities of delta 6- and delta 5-desaturases.

There is considerable evidence that under experimental conditions, oxygen free radicals (OFRs) are decisive in the pathogenesis of ischemia-reperfusion injury. Normally OFRs are scavenged by antioxidants such as alpha-tocopherol. Thus, in the following study we investigated whether antioxidants are consumed locally in human pancreatic grafts after reperfusion. A series of ten patients receiving bladder-drained pancreaticoduodenal and renal allografts were studied. Sequential blood samples were drawn locally from the venous outflow of the graft and simultaneously from the radial artery after reperfusion. alpha-Tocopherol, retinol, lycopene, and alpha- and beta-carotene levels were determined. After reperfusion these levels remained largely unchanged. Hence, in our study a consumption of antioxidants locally in the pancreatic graft after transplantation was not demonstrated. Therefore, the antioxidant capacity seems not to be exhausted at that time. This suggests that in clinical pancreatic transplantation oxidant stress in the initial reperfusion period might not have the relevance suggested by animal models.

Purpose: To evaluate the hypocalcemic effect and safety of three different doses of the bisphosphonate ibandronate in tumor-associated hypercalcemia, and to identify factors predicting response., Patients and Methods: One hundred seventy-four cancer patients with a serum calcium level greater than 2.7 mmol/L (10.8 mg/dL) were enrolled onto the trial. If hypercalcemia persisted after fluid repletion, patients were randomly assigned to treatment with 0.6 mg, 1.1 mg, and 2.0 mg of ibandronate. Response, defined as restoration of normocalcemia, was evaluated by an intent-to-treat analysis., Results: One hundred seventy-three (99%) patients were assessable for toxicity and 151 (87%) for efficacy. The administration of 0.6 mg (group A), 1.1 mg (group B), or 2.0 mg (group C) of ibandronate led to response rates of 44%, 52%, and 67%, respectively. Significantly more patients in group C responded than in group A (P = .0276). Of the various parameters examined, only the initial serum calcium level (P < .0001; odds ratio, 0.083) and the dose of ibandronate (P = .0162; odds ratio, 2.094) correlated with response. One hundred ninety-five adverse events (AEs) were reported, 99 classified as serious and 96 as nonserious. Three serious and sixteen nonserious AEs were considered related to ibandronate treatment. The three serious AEs were one case with thrombocytopenia, one with nausea, and one with fever., Conclusion: Ibandronate therapy led to a dose-dependent reduction in serum calcium levels. The response to ibandronate treatment correlated negatively with the initial serum calcium level and positively with the dose administered. A dose of 2 mg was necessary to achieve a response rate comparable to that in previous studies with the bisphosphonates pamidronate and clodronate. Because the incidence of drug-associated AEs was low, a dose escalation of ibandronate can be recommended for further clinical trials.

Aim: The assessment of the value of the antibody QBEND10, which is directed against the haemopoietic stem cell related antigen CD34, in the immunohistochemical diagnosis of myelodysplastic syndrome in routinely processed bone marrow biopsy specimens., Methods: 581 formalin fixed, paraffin embedded trephine biopsy specimens of the iliac crest were immunostained with QBEND10 (avidin-biotin complex/ABC method). The number of CD34+ haemopoietic stem cells/blast cells (referred to hereafter as CD34+ cells) was determined in each case. The Wilcoxon test was used for statistical analysis., Results: The following diagnostic categories were defined: (1) normal or reactive bone marrow (n = 356), (2) lymphoproliferative disorders, usually non-Hodgkin's lymphoma of low grade malignancy or multiple myeloma (n = 118), (3) myelodysplastic syndrome (n = 22), (4) acute leukaemia (n = 44), and (5) myeloproliferative diseases (n = 41). The average number of CD34+ cells was very low (0.2/HPF) in normal and reactive bone marrow, in lymphoproliferative disorders and in the myelodysplastic syndrome subtypes RA and RARS. Myeloproliferative diseases showed an average of three CD34+ cells/HPF. However, the average number of CD34+ cells was significantly higher (p < 0.05) in the myelodysplastic syndrome subtypes RAEB and RAEB-T (8.7/HPF) and in acute leukaemia (including both myeloid and lymphoblastic leukaemia; 111.7/HPF)., Conclusions: QBEND10 is of value for the identification of RAEB and RAEB-T in routinely processed bone marrow biopsy specimens because it enables the detection of even small increases in the number of CD34+ cells.

Conditioning therapy preceding bone marrow transplantation usually consists of high-dose chemotherapy and total body irradiation. This is associated with acute and delayed toxic effects for several tissues, possibly related to peroxidation processes and exhaustion of antioxidants. Therefore, plasma of 22 patients was examined for alpha- and gamma-tocopherol (vitamin E), the carotenoids beta-carotene and lycopene, retinol, and ascorbic acid before, during and after conditioning chemotherapy for bone marrow transplantation. 18 of the patients received total body irradiation as well. Retinol and ascorbic acid have been given intravenously in a multiple of the recommended doses (Deutsche Gesellschaft für Ernährung (DGE) and Recommended Dietary Allowance (RDA), respectively). The doses chosen were sufficient to maintain the initial plasma concentrations of these vitamins. However, alpha-tocopherol (in RDA doses) and beta-carotene (no RDA established) concentrations deteriorated after the conditioning therapy (20% and 50% loss, respectively). The loss of these lipid-soluble antioxidants has been considered to result from lipid peroxidation, since lipid peroxide concentrations in plasma increased concurrently. On the basis of these results we performed interventions studies in order to investigate the effect of high-dose supplementation on antioxidant status. We compared the loss of antioxidants and the toxicity in two groups of patients undergoing bone marrow transplantation: The first group without and the second group with oral supplementation of high doses of alpha-tocopherol (825 mg daily), ascorbic acid (450 mg daily) and beta-carotene (45 mg daily) for three weeks prior to chemo- and radiotherapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Bisphosphonates have been shown to be effective in lowering serum calcium levels in patients with cancer-associated hypercalcemia. 1-Hydroxy-3-(methylpentylamino)propylidenebisphosphonate (BM 21.0955) was developed as a third generation bisphosphonate and has been recently proven effective in animals and in patients with Paget's disease or tumor osteolysis. Thirty-six patients with cancer-associated hypercalcemia were treated with increasing doses (0.2-2.0 mg) of BM 21.0955 by single i.v. infusion over 4 h in a phase I trial. Six patients were rejected from analysis due to concomitant treatment with other bisphosphonates or chemotherapy. After rehydration and infusion of BM 21.0955 the mean serum calcium levels fell significantly (P < 0.001), from 3.29 +/- 0.49 mmol/l to 3.04 +/- 0.44 mmol/l until day 2 and normalized on day 6 (2.66 +/- 0.33 mmol/l). Serum calcium was reduced in all patients and normalized in 16. No symptomatic hypocalcemia occurred. Mean serum creatinine decreased significantly (P < 0.01), from 1.25 +/- 0.58 mg/dl (day 0) to 1.05 +/- 0.37 mg/dl (day 6). The mean urinary calcium/creatinine concentration fell significantly (P < 0.001), from 1.90 +/- 1.16 mM/mM (day 0) to 0.37 +/- 0.34 mM/mM/l (day 6). There were no subjective drug-related side effects during or after the infusion. Thirteen patients had elevations of morning body temperature above 38 degrees C. This was due to confirmed infections in five patients and possibly drug- or tumor-related in the other eight. We conclude from these preliminary results that a single infusion of BM 21.0955 is an effective and safe way to treat cancer-associated hypercalcemia.

The effects of daily dietary supplementation for 6 weeks with either 4.5 g eicosapentaenoic acid (EPA) and 3.35 g docosahexaenoic acid (DHA) (group I, EPA/DHA = 1.33) or 3.5 g EPA and 6.4 g DHA (group II, EPA/DHA = 0.54) on platelet responsiveness to the stable prostaglandin (PG)-endoperoxide analogue 9,11-dideoxy,9 alpha-11 alpha-methanoepoxy-PGF2 alpha (U 46619) were studied in healthy volunteers. Dose-response curves (DRC) of U 46619-induced platelet aggregation were analysed by computerized non-linear curve fitting. In group I, the concentration of U 46619 required for half-maximum platelet aggregation (EC50) remained unchanged, whereas the Hill coefficient decreased from 6.2 to 3.3 (P < 0.02). In group II, characterized by a high intake of DHA, a considerable increase of EC50 from 0.3 to 1.4 microM was found (P < 0.02). These results suggest different effects of EPA and DHA on the platelet thromboxane/endoperoxide-amplifying system. The considerable shift of the DRC in group II suggests a direct effect of DHA on the presentation of the endoperoxide receptor and/or post-receptoral events.

In 1989, a prospective randomized multicenter study was initiated in order to determine the safety and efficacy of oral clodronate in myeloma patients. The primary objective of this long-term trial is to evaluate whether supportive clodronate is able to prevent or retard the progression of bone disease and reduce the occurrence of characteristic complications: pain, pathologic fractures, and hypercalcemia. We now report first results as an interim analysis, including data obtained from 26 patients (total number of Tübingen patients n = 36) who entered the study at the Medizinische Universitätsklinik Tübingen. Patients were randomized to receive either chemotherapy alone (melphalan 15 mg/m2 i.v. on day 1 and prednisolone 60 mg/m2 orally on days 1-4 every 4 weeks (control group) or in combination with 1600 mg clodronate/day orally as a single dose for a period of at least 1 year. Repeated radiologic examinations in addition to hematologic and biochemical analysis were performed in order to evaluate the skeletal status with respect to lytic bone lesions and osteoporosis and the course of serum M protein and light chain excretion into urine. Clodronate treatment resulted in a significant decrease of serum calcium concentrations and of biochemical indices for bone resorption. No clodronate-related toxicity or hypocalcemia was observed. In patients treated with chemotherapy alone, this effect was less marked and discontinuous. Clodronate-treated patients developed fewer progressive bone lesions (significant for lytic, not for osteoporotic lesions). No hypercalcemic episodes occurred in the clodronate-treated patients, but there were six episodes in the control group. Whereas the number of vertebral fractures was evidently less is clodronate-treated patients, three of those patients suffered from multiple fractures of long bones and ribs. All together, 12 pathologic fractures occurred in five clodronate-treated patients, whereas in the control group 23 pathologic fractures occurred in the same number of patients during the whole observation period. The final analysis of all multicenter included patients should clarify these findings. There was a significant finding that clodronate proved to have an analgesic effect.

Plasma from 22 patients was examined for alpha- and gamma-tocopherol (vitamin E), the carotenoids beta-carotene (provitamin A) and lycopene, retinol (vitamin A), and ascorbic acid (vitamin C) before, during and after conditioning chemotherapy for bone marrow transplantation, 18 of these received total body irradiation as well. In addition, alpha-tocopherol in red blood cell membranes was measured. Retinol and ascorbic acid have been applied in multiple of the recommended doses (Deutsche Gesellschaft für Ernährung and Recommended Dietary Allowance, respectively). The chosen doses were sufficient to maintain the initial plasma concentrations of these vitamins. However, alpha-tocopherol (in RDA doses) and beta-carotene (no RDA established) concentrations deteriorated after the conditioning therapy (20 and 50% loss, respectively). The loss of these lipid-soluble antioxidants has been considered to result from lipid peroxidation. On the basis of the presented results we propose intervention studies to investigate the effect of high dose antioxidant administration on the toxicity (mainly of liver and lung) of intensive antineoplastic therapy protocols.

During the past decade, remarkable progress has been made in our understanding of cancer-causing agents, mechanisms of cancer formation and the behavior of cancer cells. Cancer is characterized primarily by an increase in the number of abnormal cells derived from a given normal tissue, invasion of adjacent tissues by these abnormal cells, and lymphatic or blood-borne spread of malignant cells to regional lymph nodes and to distant sites (metastasis). It has been estimated that about 75-80% of all human cancers are environmentally induced, 30-40% of them by diet. Only a small minority, possibly no more than 2% of all cases, result purely from inherent genetic changes. Several lines of evidence confirm that the fundamental molecular event or events that cause a cell to become malignant occur at the level of the DNA and a variety of studies indicate that the critical molecular event in chemical carcinogenesis is the interaction of the chemical agent with DNA. The demonstration that DNA isolated from tumor cells can transfect normal cells and render them neoplastic provides direct proof that an alteration of the DNA is responsible for cancer. The transforming genes, or oncogenes, have been identified by restriction endonuclease mapping. One of the characteristics of tumor cells generated by transformation with viruses, chemicals, or radiation is their reduced requirement for serum growth factors. A critical significance of electrophilic metabolites of carcinogenes in chemical carcinogenesis has been demonstrated. A number of "proximate" and "ultimate" metabolites, especially those of aromatic amines, were described. The "ultimate" forms of carcinogens actually interact with cellular constituents to cause neoplastic transformation and are the final metabolic products in most pathways. Recent evidence indicates that free radical derivatives of chemical carcinogens may be produced both metabolically and nonenzymatically during their metabolism. Free radicals carry no charge but do possess a single unpaired electron, making the radical extremely reactive. That such forms may be important in the introduction of neoplastic transformation by chemicals from two lines of evidence. (1) Various molecules that inhibit the formation of free radicals, many of which are termed antioxidants, can inhibit the carcinogenic action of a variety of chemical carcinogens. (2) There are relatively specific metabolic reactions of certain chemical carcinogens, particularly of polycyclic hydrocarbons, for which it has been shown to proceed through free radical intermediates. In conclusion, free radical processes with direct effects on DNA can be proposed for a variety of human and animal carcinogens.(ABSTRACT TRUNCATED AT 400 WORDS)

The course of disease in 119 HIV-infected patients (117 men, 2 women; median age 38.5 years) with malignant tumours other than Kaposi's sarcoma was analyzed in a multi-centre retrospective study. This was conducted to obtain initial information concerning the incidence, clinical features and results of therapy in HIV-associated neoplasms, especially malignant lymphomas. The most frequent tumour was malignant non-Hodgkin's lymphoma (98 patients, 82.5%), seven patients had Hodgkin's disease, five had solid tumours, four a polyclonal lymphoproliferative syndrome, three an acute lymphocytic leukaemia, and two had other lymphoproliferative diseases. 58% of the non-Hodgkin's lymphomas occurred in patients with marked immunodeficiency, 85% were high grade malignancies and 47% had primary extranodal disease. 56% of primary nodal lymphomas also had visceral spread (Stage IV). Lymphoblastic non-Hodgkin's lymphoma was more common in patients with favourable immunological status, presented less frequently with primary extranodal disease, was diagnosed earlier than other non-Hodgkin's lymphomas, and appeared to carry a better prognosis. 78 out of the 98 patients with non-Hodgkin's lymphoma had been treated, 66 with cytotoxics. The median survival time was 6 months. Longer remission periods, of at least 12 months, were seen in ten of the 78 patients (13%). Despite the overall poor prognosis and the pre-existing immune defect, palliative (chemo-)therapeutic measures are both justified and promising, and may also result in life-prolonging remissions.

Various pathological disorders are accompanied by the deposition of lipids into glomerular cells. To gain insight into these disorders, it is essential to know if glomerular cells possess lipoprotein receptors. We therefore characterized the activity of lipoprotein receptors in cultured epithelial cells of the human glomerulus. Podocytes were chosen as they are directly exposed to lipoproteins in pathological states like in glomerular proteinuria (such as, nephrotic syndrome). Isolated human glomeruli (purity greater than 95%) were incubated in buffered RPMI 1640 medium supplemented with 20% heat-inactivated fetal bovine serum at 37 degrees C and 5% CO2. Outgrowing cells were vimentin and keratin positive. Monolayer cultures of human glomerular epithelial cells upon incubation in lipoprotein deficient serum for 48 hours expressed a receptor-dependent uptake of lipoproteins. These cells showed about 10% of the maximal capacity for LDL uptake as compared to fibroblasts; however, the Km values for binding, internalization and degradation were similar in the cultures of glomerular epithelial cells and fibroblasts. The Km values for degradation of LDL, chylomicron remnants, beta-VLDL from cholesterol-fed rabbits and VLDL from familial LCAT-deficiency patients were 14.2, 4.9, 2.9, 4.5 micrograms protein/ml medium, respectively, for glomerular epithelial cells. The avid uptake of 125I-labeled apo E-containing lipoproteins was further substantiated by their poor displacement by a 25-fold excess of unlabeled LDL and their ability to down regulate the apo B,E receptor activity. LDL as well as beta-VLDL were able to suppress the incorporation of 14C acetate into sterols and to stimulate 3H-cholesterylester formation. These experiments show that cultured glomerular epithelial cells express lipoprotein receptor activity. Plasma concentrations of apo E-containing lipoproteins are increased in certain renal diseases (such as, nephrotic syndrome); these lipoproteins could be rapidly removed by glomerular epithelial cells and lead to lipid deposition in glomeruli.

Lipid peroxidation in erythrocytes is currently studied by measuring the formation of malonyldialdehyde (MDA). A new and simple methodological approach to the measurement of the extend of lipid peroxidation is described here. Erythrocytes from freshly drawn human blood were washed and suspended in isoosmotic phosphate-buffered saline and incubated with sodium azide to inhibit the catalase. Oxidation of red cell lipids was induced by the addition of hydrogen peroxide. MDA formation was measured by the 2-thiobarbituric acid (TBA) reaction. After the same procedure of incubation the production of volatile alkanes (pentane, ethane, ethylene, n-butane, and propane) was estimated by gas chromatography. The total amount of pentane formation from red cells after 120 min of incubation with hydrogen peroxide was much higher than of the other alkanes. This assay provides a useful model to elucidate the role of lipid peroxidation of erythrocytes and is a simple method to study changes in their membrane lipid in diseases and red cell aging.

Human red blood cells and male Sprague-Dawley rats were treated in vitro and in vivo, respectively, with phenylhydrazine in order to determine whether the release of volatile hydrocarbons can serve as a suitable index for phenylhydrazine-induced red blood cell peroxidation. Lipid peroxidation following phenylhydrazine administration (in vitro experiments: dosage calculated at 0.5-50 mM; in vivo experiments: intraperitoneal injection of 2.8 mg/100 g body wt) was monitored by the release of ethane and pentane measured by gas chromatography. Further hydrocarbons such as ethylene, propane, n-butane, iso-butane and iso-butene were monitored to form a basis of comparison. In vitro haemolysis was also determined during the course of incubation. Red blood cell suspensions yielded more than 15-fold concentrations of propane and more than 2-fold concentrations of iso-butane compared to pentane and ethane yields. Haemoglobin solutions also produced propane and iso-butane in the presence of phenylhydrazine, whereas pentane and ethane were not detectable. Time-course studies revealed that ethane and pentane reached maximum in vitro levels after red blood cell suspensions had been incubated for 2 hr whereas the maximum degree of haemolysis (approximately 60%) was attained between 60 and 90 min following the beginning of phenylhydrazine treatment. The dosage did not affect the final degree of haemolysis. Rats treated with phenylhydrazine exhaled greater concentrations of ethane (6-fold increase) and pentane (2-fold increase) compared to control animals. Exhaled propane showed a 30-fold increase in concentration following drug treatment. Our results suggest that the release of pentane and ethane may be useful in assessing red blood cell lipid peroxidation in the presence of phenylhydrazine in vitro and in vivo.

Red blood cells from 31 healthy donors were examined for the cholesterol content, the fatty acid composition, and the susceptibility to lipid peroxidation induced by either hydrogen peroxide or phenylhydrazine. Lipid peroxidation was monitored by the release of pentane and ethane. In addition, plasma fatty acids were measured in order to find out, whether plasma and red cell fatty acids were correlated. In experiments with hydrogen peroxide, a significant positive correlation was found between the proportion of arachidonic acid (C 20:4n - 6; r = 0.57, p less than 0.01) and docosahexaenoic acid (C 22:6n - 3; r = +0.71, p less than 0.01), and the release of pentane and ethane, respectively. A significant negative correlation was found between the membrane cholesterol content and the pentane release (r -0.44, p less than 0.05). In experiments performed with phenylhydrazine, red cell membrane lipid composition did not influence the susceptibility of red cells to lipid peroxidation. A close correlation was found between plasma and red cell fatty acids (palmitic acid, r = +0.46, p less than 0.01; linoleic acid, r = +0.41, p less than 0.05; arachidonic acid, r = +0.59, p less than 0.01; docosahexaenoic acid, r = +0.67, p less than 0.01). The results demonstrated that the degree of peroxide-induced oxidation of erythrocyte lipids depends on the content of polyunsaturated fatty acids in the membrane, which on the other hand, is determined by plasma fatty acids. It is suggested that dietary variations may influence the susceptibility of red cells to lipid peroxidation.

The present study investigates the effect of ascorbate on red cell lipid peroxidation. At a concentration between 0.2 mmol - 20 mmol/1 ascorbic acid reduces hydrogen peroxide-induced red blood cell lipid peroxidation resulting in a marked decrease in ethane and pentane production as well as in haemolysis. Ascorbic acid also shows an antioxidant effect on chelated iron-catalyzed hydrogen peroxide-induced peroxidation of erythrocyte membranes. At a concentration of 10 mmol/1 ascorbic acid totally inhibits oxidative break-down of polyunsaturated fatty acids by radicals originating from hydrogen peroxide. Our results indicate that ascorbate at the chosen concentration has an antioxidant effect on red blood cell lipid peroxidation.