Neuroblastoma and parental occupation

Objectives: We evaluated parental occupation and the risk of neuroblastoma using data from a large case–control study conducted by the Children's Cancer Group and the Pediatric Oncology Group.Methods: We compared the distribution of 73 paternal and 57 maternal occupational groups among 504 newly diagnosed cases of neuroblastoma and individually matched controls obtained by telephone random digit dialing in the United States and Canada.Results: An increased risk of neuroblastoma was found for fathers employed as broadcast, telephone and dispatch operators (odds ratio [OR]=6.1; 95% confidence interval [CI]=0.7–50.9), electrical power installers and power plant operators (OR=2.7; CI=0.9–8.1), landscapers and groundskeepers (OR=2.3; CI=1.0–5.2), and painters (OR=2.1; CI=0.9–4.8). Elevated odds ratios were found for mothers employed as farmers and farm workers (OR=2.2; CI=0.6–8.8), florists and garden store workers (OR=2.4; CI=0.6–9.9), hairdressers and barbers (OR=2.8; CI=1.2–6.3), electric power installers and power plant operators, and sailors, fishers, and railroad workers. No increase in risk was found for other paternal occupations previously associated, including electricians, electrical equipment assemblers and repairers (OR=1.1; CI=0.6–2.0), or welders (OR=0.5; CI=0.1–1.6).Conclusion: The study reinforced some prior evidence of increased risks in electrical, farming and gardening, and painting occupations, but failed to confirm other previously reported associations. Further analyses of exposure to electromagnetic fields, metals, solvents, and pesticides are currently under way.     

High-dose chemotherapy with autologous stem cell rescue for children with high risk and recurrent medulloblastoma and supratentorial primitive neuroectodermal tumors

Current treatment for high risk and recurrent medulloblastoma (MB) and supratentorial primitive neuroectodermal tumors (stPNET) has a very poor prognosis in children. High dose chemotherapy (HDCT) and autologous stem cell rescue have improved survival rates. We present 19 patients (thirteen classified in the high risk group and six patients with recurrent disease) that received HDCT and autologous stem cell rescue.In the high risk group [Med Pediatr Oncol 38 (2002) 83], all patients underwent neurosurgical debulking. Standard chemotherapy was prescribed in 10 patients. Radiotherapy was given to 4 patients (all older than 4years old). In the recurrence disease group [Childs Nerv Syst 15 (1999) 498], five patients underwent surgery. Radiotherapy was given to those who were not previously irradiated. The HDCT in twelve patients consisted of busulfan 4mg/kg/day, orally over 4days in 6-hourly divided doses and melphalan at a dose of 140mg/m²/day by intravenous infusion over 5min on day –1. Three patients additionally received thiotepa 250mg/m²/day intravenously over 2days and four patients additionally received topotecan 2mg/m²/day over 5days by intravenous infusion over 30min. The other seven patients received busulfan and thiotepa at the same doses.Patients stem cells were mobilized with granulocyte colony-stimulating factor at a dose of 12g/kg twice daily subcutaneously for four consecutive days. Cryopreserved peripheral blood progenitor cells were re-infused 48h after completion of chemotherapy. With a median follow-up of 34months (range 5–93) eight complete responses and one partial response were observed. Three patients died of treatment-related toxicities (15%). The 2 year event-free survival was 37.67±14% in all patients and 57±15% for the high risk group.Therefore we conclude that HDCT may improve survival rates in patients with high risk/recurrent MB and stPNET despite treatment toxicity.     

Impact of videotaped information on frequency and confidence of breast self-examination

Background Videotaped education materials to teach breast self-examination (BSE) are used worldwide. However, evaluation of videotaped BSE instructions is lacking. Methods Premenopausal women (mean age 33.4±11.2 years) without history of breast cancer were approached to participate in this experimental study and randomly assigned to a video intervention group (VG; n=130; length of the video=15 min) or non-video comparison group (NVG; n=121). All participants answered a questionnaire on BSE behavior and health beliefs. No additional training was given. The total duration of the session including completion of the questionnaire was 15min for the NVG and 30min for the VG. Three months later, changes in BSE behavior were compared in the two groups. The influence of health beliefs on actual BSE behavior was investigated as well. Results Women of both the VG and NVG performed BSE significantly more frequently at follow-up than at baseline. Analysis of covariance, using the baseline BSE-frequency as co-variate and the follow-up BSE frequency as the dependent variable, revealed that women in the VG (adjusted mean=7.9 times per year, 95%CI=6.5–9.4) performed BSE more frequently than women of the NVG (adjusted mean=6.1 times per year, 95%CI=4.6–7.5) (F=4.2, df=2, p=0.02). Among motivational predictors, having an example of a role model (modeling) was shown by regression analysis to explain the greatest amount of variance (13%) in BSE frequency. Conclusion Use of an educational videotape increased the frequency of BSE among premenopausal women.     

Irofulven Induces Apoptosis in Breast Cancer Cells Regardless of Caspase-3 Status*

Caspase-3 deficiency can limit the efficiency of pro-apoptotic anticancer treatments. Irofulven (hydroxymethylacylfulvene, HMAF, MGI 114, NSC 683863) is an antitumor drug, currently in a Phase III and multiple Phase II trials, which can differentiate between tumor and normal cells in apoptosis induction. This study investigated whether apoptosis induced by irofulven requires caspase-3. Irofulven action was compared in breast cancer cells differing in caspase-3 status: deficient MCF-7 cells and proficient MDA-MB-231 cells and in normal human mammary epithelial cells, HMEC. Irofulven induces significant, concentration and time-dependent apoptotic DNA fragmentation in breast cancer cell lines, regardless of caspase-3 status. After 12, 24 and 48h incubation at 1M irofulven ( 3×GI₅₀), fragmented DNA comprised 3.7, 14.1 and 34.6% and 8.4, 12.6 and 20.3% of total DNA in MCF-7 and MDA-MB-231 cells, respectively. Cell viability (trypan blue exclusion) remained largely unaffected during the first 24h but decreased markedly after 48h, indicating secondary necrosis. Net losses in cell numbers were apparent at 48h. Normal HMEC cells were refractory to 1M drug with only 3–9% fragmented DNA after 12–48h, although apoptosis was observed at drug levels >3M. The broad-spectrum caspase inhibitor Z-VAD-fmk inhibited irofulven-induced apoptosis of all cell lines at 20M with nearly complete abrogation of apoptosis at 100M. Irofulven treatment resulted in marginal caspase-3 processing in MDA-MB-231 and HMEC cells. These results indicate that whereas the caspase cascade mediates irofulven- induced apoptosis, caspase-3 is dispensable (supported by NIH CA70091 and CA78706).     

Distribution of Small Magnetic Particles in Brain Tumor-bearing Rats

Small (10–20nm) uncharged magnetic particles (SMP) were evaluated for their ability to target intracerebral rat glioma-2 (RG-2) tumors in vivo. In an effort to determine the influence of particle size on blood-tumor barrier uptake, the tissue distribution of the injected particles was evaluated following intraarterial injection (4mg/kg SMP) in male Fisher 344 rats bearing RG-2 tumors with a magnetic field of 0G or 6000G applied to the brain for 30min. Animals were sacrificed at 30min or 6h post-injection after which tissues were collected and analyzed for magnetite content. In the presence of a magnetic field, SMP localized in brain tumor tissue at levels of 41–48% dose/g tissue after 30min and 6h respectively, significantly greater than non-target tissues. In the absence of a magnetic field only 31–23% dose/g tissue was achieved for the same time points. Tumor targeting of the SMP for brain tumor was demonstrated by large target selectivity indexes (ts) of 2–21 for normal brain tissue, indicating a 2–21 fold increase in concentrations compared to normal brain. In comparison with larger (1µm) diameter magnetic particles, SMP concentrated in brain tumor at significantly higher levels than magnetic neutral dextran (p=0.0003) and cationic aminodextran (p=0.0496) microspheres previously studied. TEM analysis of brain tissue revealed SMP in the interstitial space of tumors, but only in the vasculature of normal brain tissue. These results suggest that changes in the vascular endothelium of tumor tissue promote the selective uptake of SMP and provide a basis for the design of new small drug-loaded particles as targeted drug delivery systems for brain tumors.     

Flow cytometric analysis of primary tumors and their corresponding metastatic nodes in breast cancer

Human breast carcinoma is biologically heterogeneous, and its clinical course may vary from one which is indolent to one which rapidly progresses. Although it is the metastasis rather than the primary tumor that ultimately overwhelms the patients, studies concerning the DNA pattern have focused on the primary tumors. This study was undertaken to identify heterogeneities between primary tumors and metastases, and to evaluate the prognostic significance of the ploidy pattern and the S-phase fraction (SPF) of metastatic nodes in axillary node positive patients. Seventy-four frozen specimens of the primary and corresponding metastatic nodes from 37 patients have been analyzed by flow cytometry and the SPF calculated. The results of ploidy pattern analysis in primaries revealed 25 diploidy (67.6%) and 12 aneuploidy (32.4%), while those in metastasis showed 17 diploidy (46.0%) and 20 aneuploidy (54.0%). The aneuploidy group in metastatic nodes had the poorer histological grade (85.0% vs. 15.0%, p=0.02), and more mean metastatic nodes (5.75±2.10 vs. 3.05±1.56, p=0.018), and more frequent lymphatic vessel invasion (65.0% vs. 11.8%, p=0.031) than its counterpart. Decreased expression of ER (70.6% vs. 25.0% p=0.006) and increased expression of c-erbB2 (65.0% vs. 23.5%, p=0.012) were observed in the aneuploidy of metastatic nodes. The group with higher SPF in metastatic nodes had more metastatic nodes (5.47±2.31 vs. 4.00±1.78, p=0.042), and the higher incidence of lymphatic vessel invasion (57.9% vs. 22.2%, p=0.027), and poor histological grade (71.4% vs. 37.5%, p=0.039). In conclusion, the cell populations in metastatic nodes revealed DNA pattern which differed from that of primary tumors. The ploidy pattern and SPF in metastatic nodes might be considered as discriminate measure for risk factors in breast cancer patients with positive axillary node.     

Prognostic significance of acute presentation with emergency complications of gastric cancer

Background Although acute complications necessitating emergency hospital admission are well documented in patients with carcinoma of the colon, comparable data for patients with gastric carcinoma is thin. The aim of this study, therefore, was to examine the outcomes of patients presenting to hospital as acute admissions with emergency complications of previously undiagnosed gastric cancer.Methods Three hundred consecutive patients with gastric adenocarcinoma were studied prospectively, and subdivided into two groups according to whether the patients were referred as acute emergencies (n = 116) or as outpatients (n = 184).Resuslts The commonest emergency complications were: abdominal pain (57%), vomiting (41%), gastrointestinal bleeding (37%), dysphagia (26%), and a palpable mass (18%). Stages of disease were significantly more advanced in patients presenting acutely (I:II:III:IV = 7:11:27:71) compared with patients referred via outpatients (20:23:50:91, ² = 3.955; DF, 1; P = 0.047). R0 gastrectomy was significantly less likely after acute presentation (23 patients; 20%) compared with patients referred via outpatients (70 patients; 38%; ² = 11.037; DF, 1; P = 0.001). Cumulative 5-year survival for patients referred acutely was 9%, compared with 22% after outpatient referral (² = 9.11; DF, 1; P = 0.0025). Multivariate analysis revealed two factors to be significantly and independently associated with durations of survival: stage of disease (hazard ratio [HR], 1.742; 95% confidence interval [CI], 1.493–2.034; P = 0.0001) and presentation with acute complications (HR, 1.561; 95% CI, 1.151–2.117; P = 0.004).Conclusion Emergency complications of gastric cancer are a significant and independent prognostic marker of poor outcome.Presented at: British Society of Gastroenterology, Birmingham 2003, and 5th International Gastric Cancer Congress, Rome 2003.     

Prevention of rat mammary carcinoma utilizing leuprolide as an equivalent to oophorectomy

A clinical trial is currently under way to examine the effectiveness of leuprolide as a breast cancer chemopreventive agent and contraceptive. This trial, as well as similar proposed studies, is based on the assumption that leuprolide is as effective as surgical castration in preventing the onset of mammary tumors; however, this has not been well documented in the DMBA animal model. We directly compared leuprolide and oophorectomy in this model and examined a combined therapy of leuprolide/bromocriptine. Twenty-seven day old female Sprague-Dawley rats were randomly allocated into one of eight groups. All rats received a 20-mg dose of DMBA at the age of 55 days. Group 1 (n=10), no treatment; Group 2 (n=9), leuprolide (100g/kg/day) for eight weeks beginning four weeks prior to DMBA; Group 3 (n=10), oophorectomy four weeks prior to DMBA with replacement estrogen beginning four weeks following DMBA. Estrogen replacement was achieved with a 0.05-mg estradiol tablet releasing 0.833g/day over a 60-day period. Group 4 (n=10), leuprolide (100g/kg/day) initiated two weeks prior to DMBA and continuing for two weeks following DMBA; Group 5 (n=9), oophorectomy two weeks prior to DMBA with 0.05mg of estradiol in depot form, releasing 0.833g/day, beginning four weeks following DMBA and continuing until week 16 of the study; Group 6 (n=10), leuprolide (100g/kg/day) beginning two weeks prior to DMBA and continuing for the duration of the experiment; Group 7 (n=10), leuprolide (100g/kg/day) for eight weeks beginning two weeks prior to DMBA; Group 8 (n=9), leuprolide (100g/kg/day) and bromocriptine (83g/day) for eight weeks beginning two weeks prior to DMBA. At nineteen weeks (15 weeks post DMBA), animals were sacrificed and autopsies performed. One hundred percent of untreated animals developed tumors. No animals undergoing oophorectomy four weeks prior to DMBA or receiving leuprolide four weeks prior to and simultaneously with DMBA developed tumors. In animals pretreated two weeks prior to DMBA with leuprolide or oophorectomy, each group had one animal with tumor development. No tumors developed in the animals receiving ongoing injections of leuprolide. However, one tumor developed in those receiving leuprolide for the first eight weeks beginning two weeks prior to DMBA administration. One animal receiving both leuprolide and bromocriptine developed one tumor. We conclude that chemical oophorectomy (with leuprolide) is as effective as surgical oophorectomy in inhibiting DMBA induced carcinogenesis.     

Relationship between the morphological and biological characteristics of intraductal components accompanying invasive ductal breast carcinoma and patient age

We divided 324 cases with invasive ductal breast carcinoma into three age groups, and investigated the differences in proliferative activity and extension of the intraductal components among the age cohorts. Proliferative activity was expressed as the number of MIB1-positive nuclei per 1000 cancer cells in the intraductal components (MLI), and the intraductal component extension farthest from the invasive focus was defined as the maximum distance of ductal spread (MXDS). Moreover, analyses were conducted for three grade types, classified according to the classification system of ductal carcinoma in situ. The under-40 age group had significantly higher MXDS values than the other two age groups (p=0.0280), and this trend was more marked in those with the non-high grade without necrosis type (p=0.0045). The under-40 age group had higher MLIs, but the differences did not reach statistical significance (p=0.0793). In regard to those with the high grade type, the under-40 age group had significantly higher MLIs than the other two age groups (p=0.0269), and this trend was not significant in the cases with any other grade types. Associations between the age group and the margin status of the lumpectomy specimens were investigated in the 143 cases in which breast conserving surgery was tried. The under-40s had a significantly higher margin-positive rate in their lumpectomy specimens than the other two age groups (p=0.0362), and this trend was also seen in the groups with the non-high grade without necrosis type (p=0.0256). These results confirm the importance of considering patient age when designing surgical procedures for breast conserving therapy.     

Effect of Dose and Infusion Time on the Delivery of p-boronophenylalanine for Neutron Capture Therapy

Clinical trials of boron neutron capture therapy (BNCT) for glioblastoma multiforme are currently in progress using p-boronophenylalanine (BPA) as the 10B delivery agent. Enhancement of tumor boron uptake and/or the tumor-to-blood (T:B) boron concentration ratio would have the potential of significantly improving the therapeutic gain of BNCT. The effects of total dose, infusion time, and route of administration of BPA on tumor and blood boron concentrations were studied in rats bearing the 9L gliosarcoma. Increasing the total dose of BPA from 250 to 1000mg/kg, administered intravenously over a 2-h infusion period, resulted in an increase in tumor boron concentration from 30 to 70µg 10B/g, with a constant T:B boron concentration ratio of about 3.7:1. Similarly, extension of the infusion time from 2 to 6h, at a constant dose-rate of 125mg BPA/kg/h, resulted in an increase in tumor boron concentration from 30 to 80µg 10B/g, while, again, maintaining a constant T:B ratio of about 3.7:1. In contrast, intracarotid infusion of BPA for 1h at a dose rate of 125mg BPA/kg resulted in an increase in the tumor boron concentration from 26 to 38µg 10B/g with a corresponding increase in the T:B ratio from 3.5:1 to 5.0:1. The effects of these results on the therapeutic gain potentially achievable with BNCT are discussed.     

Inflammatory Breast Cancer Survival: The Role of Obesity and Menopausal Status at Diagnosis

No previous studies have evaluated the effect of body size and menopausal status at diagnosis on survival from inflammatory breast cancer (IBC). We evaluated whether obesity and menopausal status had an impact on IBC survival in a cohort of 177 female IBC patients seen from 1974 to 1993 at The University of Texas MD Anderson Cancer Center. Survival time was defined as time from diagnosis until death or censorship at last date of contact. We categorized women by body size by using the National Institutes of Health/National Heart, Lung, and Blood Institute's definitions of obesity as body mass index ((BMI)=weight in kg/(height in m)²)30, overweight as 25BMI <30kg/m², and normal/lean as BMI <25kg/m². Cox proportional hazards analysis, adjusting for axillary lymph node involvement and chemotherapy protocol, revealed a modifying effect of menopausal status at diagnosis on the association between obesity and IBC survival (P=0.02). Relative to postmenopausal women, premenopausal women had significantly worse survival (hazard ratio (HR)=1.51, 95% confidence interval (CI)=1.03–2.22). After stratifying by menopausal status, premenopausal obese women had non-significantly better survival than their leaner premenopausal counterparts (HR=0.63, 95% CI=0.34–1.15) while postmenopausal obese women had significantly worse survival than their leaner counterparts (HR=1.86, 95% CI=1.02–3.40). These findings suggest that factors associated with larger body size at diagnosis may contribute to shorter IBC survival among postmenopausal women but not premenopausal women, who were found to have poorer survival regardless of body size.     

Differential Effect of Cycloheximide on Neuronal and Glioma Cells Treated with Chemotherapy and Radiation

Dividing cells and non-dividing cells are distinct in their cell cycle kinetics, and react differently when facing cytotoxic stimuli. A protein synthesis inhibitor, cycloheximide (CHX), has recently been found to protect neuronal cells from oxidative stress. We investigated whether CHX exerts differential effects on dividing and non-dividing cells in the brain under cytotoxic stimuli. Mitotic C6 rat glioma cells and postmitotic neuronal cells were studied with a cytotoxic regimen combining -irradiation (RT) and 1,3-bis,2-chloroethyl-1-nitrosurea (BCNU). Cells were exposed to BCNU (1µg/ml) for 15h before -irradiation and incubated with CHX (1µg/ml) from 30min before and until 5h after irradiation. Clonogenic assay was used to assess cytotoxic effects on C6 glioma cells. LDH assay was used for the viability of H19-7 postmitotic neuronal cells. A 2.27–3.75 fold enhancement of cytotoxicity was noticed with the addition of CHX to BCNU and 2–10Gy of radiation. Our data demonstrated that CHX enhanced cytotoxocity of RT plus BCNU, while no additional toxicity was incurred to the postmitotic neuronal cells when CHX was added. We further studied whether the inhibition of DNA repair, assayed by single-cell DNA electrophoresis (comet assay), is a contributing factor for the enhanced cytotoxicity on C6 glioma cells.Interestingly, the initial DNA damage after RT plus BCNU was equivalent; whereas DNA repair was significantly less at 5h after radiation in CHX-treated C6 glioma cells. Protecting non-dividing neuronal cells to avoid excesive functional deficit is an integral part of a successful brain tumor treatment regimen. Taking advantage of the differential effect of CHX on glioma and neuronal cells may improve tumor control without excessive neural toxicity.     

Ultrastructural Changes of the Vascular Endothelium after Intra-arterial Administration of Tumor Necrosis Factor-alpha (TNFα) in Rat Gliomas

The ensuing ultrastructural changes in tumor vascular endothelial cells following intra-arterial administration of tumor necrosis factor- (TNF) were studied in an experimental rat glioma model. C6 glioma cells were implanted in Wistar rats and then after 14 days, 5×10³U of human natural-type TNF (1.7×10⁵U/m²) was administered through the carotid artery. The animals were sacrificed at 3 or 24h after TNF treatment. A detailed examination with transmission electron microscope revealed swelling of the tumor vascular endothelial cell nuclei and mitochondria with matrix densities at 3h. At 24h, these cells demonstrated the presence of high amplitude mitochondrial swelling or the violent blebbing characteristic of damaged mitochondria; the cytoplasm was swollen enormously and there were dissolution of cytoplasmic organelles and rupture of the plasma membrane. The observed findings were typical of cell necrosis and confirms yet another mechanism by which TNF exerts its anti-tumor effects, that is, necrotizing effects on tumor vascular endothelium. The information appears to be important in the context of clinical application of intra-arterial TNF in the treatment of malignant gliomas.     

Effect of the aromatase inhibitor vorozole on estrogen and progesterone receptor content of rat mammary carcinomas induced by 1-methyl-1-nitrosourea

Vorozole, a nonsteroidal aromatase inhibitor, impedes the post-initiation stage of chemically induced mammary carcinogenesis. While various aspects of vorozole's effects on mammary carcinoma development have been investigated, little attention has been directed to determining the estrogen receptor (ER) and progesterone receptor (PR) content of mammary carcinomas that arise despite vorozole treatment. Female Sprague–Dawley rats were given an i.p. injection of 50mg MNU/kg body weight at 21 days of age and placed on diet supplemented with 0 or 3mg vorozole/kg, which had no effect on mammary tumor development. Histologically confirmed carcinomas were evaluated for ER and PR by immunohistochemistry. In the control group, 78.8% of carcinomas were ER positive with an ER content ranging from 13.8 to 40.0%, similar to ER content of mammary ductal epithelial cells from non-carcinogen treated animals. PR content ranged from 4.4 to 45.2% and also was similar to levels of PR observed in ductal epithelial cells. ER was not correlated with PR in mammary carcinomas (r=0.05, p>0.80), whereas there was a significant correlation in ductal epithelium (r=0.86, p=0.006). In vorozole-treated rats, no ER negative carcinomas were observed and overall ER expression by vorozole was elevated (p<0.03). All carcinomas from vorozole-treated rats expressed PR (2.5–60.2%) and correlation between ER and PR content was numerically greater in carcinomas from vorozole-treated animals (r=0.42, p=0.09). These data, which are considered hypothesis generating, provide evidence that low doses of vorozole in the diet select for mammary carcinomas with an increased ER positive phenotype.     

Repetitive 5-aminolevulinic acid-mediated photodynamic therapy on human glioma spheroids

The response of human glioma spheroids to repetitive 5-aminolevulinic acid-mediated photodynamic therapy (PDT) was investigated. In all cases, light fluences were kept below toxic thresholds to simulate conditions typically found at 1–2cm depths in brain adjacent to tumor. Significant inhibition of spheroid growth was observed following multiple PDT treatments at sub-threshold light fluences. The effect appears to be insensitive to the treatment intervals investigated (weekly or bi-monthly). In all cases, suppression of growth was observed for the duration of treatment. Low fluence rates (5mWcm^–2) appear to be more effective than high fluence rates (25mWcm^–2). No evidence of PDT resistance was found in this investigation.     

Role of Ceramide During Cisplatin-induced Apoptosis in C6 Glioma Cells

Cisplatin is commonly used for the treatment of malignant brain tumors. However, the mechanisms of cell death by cisplatin are not fully understood. Therefore, the present study was designed to elucidate the apoptotic signaling pathway(s) activated by cisplatin in a C6 rat glioma cell line. C6 cells were treated with various concentrations of cisplatin (0.2–10g/ml) for 24–72h. At 10g/ml cisplatin, over 90% of the cells became dead at 72h. Apoptotic death was confirmed by condensation and fragmentation of nuclei, and DNA laddering. Even in cells treated with 1.5g/ml cisplatin, typical apoptotic cells were observed at 72h. The intracellular level of ceramide, measured Escherichia coli diacylglycerol kinase markedly increased during 24–72h after the addition of 10g/ml cisplatin. The activity of caspase-3(-like) proteases increased and reached a peak at 48h. Inhibitors of caspases reduced the number of apoptotic cells. Pretreatment of C6 cells with glutathione or N-acetyl-cysteine, which are known to block the activation of neutral magnesium-dependent sphingomyelinase, inhibited ceramide formation, leading to suppression of both activation of caspase-3(-like) proteases and apoptosis by cisplatin. In contrast, pretreatment of the cells with N-oleoylethanolamine (OE), a ceramidase inhibitor, potentiated apoptosis induced by cisplatin. Furthermore, OE enhanced sensitivity of the cisplatin-resistant cells to cisplatin. These results suggest that ceramide is closely implicated in apoptosis of glioma cells by cisplatin through activation of caspase-3(-like) proteases.     

Gastroesophageal reflux disease, use of H2 receptor antagonists, and risk of esophageal and gastric cancer

Objective: The incidence of esophageal adenocarcinoma has risen rapidly in the past two decades, for unknown reasons. The goal of this analysis was to determine whether gastroesophageal reflux disease (GERD) or the medications used to treat it are associated with an increased risk of esophageal or gastric cancer, using data from a large population-based case–control study. Methods: Cases were aged 30–79 years, newly diagnosed with esophageal adenocarcinoma (n=293), esophageal squamous cell carcinoma (n=221), gastric cardia adenocarcinoma (n=261), or non-cardia gastric adenocarcinoma (n=368) in three areas with population-based tumor registries. Controls (n=695) were chosen by random digit dialing and from Health Care Financing Administration rosters. Data were collected using an in-person structured interview. Results: History of gastric ulcer was associated with an increased risk of non-cardia gastric adenocarcinoma (OR 2.1, 95% CI 1.4–3.2). Risk of esophageal adenocarcinoma increased with frequency of GERD symptoms; the odds ratio in those reporting daily symptoms was 5.5 (95% CI 3.2–9.3). Ever having used H₂ blockers was unassociated with esophageal adenocarcinoma risk (OR 0.9, 95% CI 0.5–1.5). The odds ratio was 1.3 (95% CI 0.6–2.8) in long-term (4 or more years) users, but increased to 2.1 (95% CI 0.8–5.6) when use in the 5 years prior to the interview was disregarded. Risk was also modestly increased among users of antacids. Neither GERD symptoms nor use of H₂ blockers or antacids was associated with risk of the other three tumor types. Conclusions: Individuals with long-standing GERD are at increased risk of esophageal adenocarcinoma, whether or not the symptoms are treated with H₂blockers or antacids.     

Progression of Premalignant MCF10AT Generates Heterogeneous Malignant Variants with Characteristic Histologic Types and Immunohistochemical Markers

The purpose of this study was to evaluate the pain experience of women during mammography for breast cancer screening. Possible associations with personal and medical history, sociodemographics and/or situational factors were studied. It was also investigated whether this pain influenced the intention to return for future breast cancer screening. In the Netherlands, women between 50–75 years are invited for screening every two years. A total of 1200 participants were asked to fill up a questionnaire. The response rate was 79.5% (n=954), and 945 questionnaires contained adequate information for analyses. A total of 689 women (72.9%) described mammography as mild to severely painful. In this group, compared to the group that reported no pain, the following factors occurred significantly more often: sensitive breasts (P=0.001), family history of breast diseases (P=0.017), expected pain based on former mammography (P=0.001), high education (P=0.008), anxiety (P=0.001), breast sensitivity in last three days (P=0.001), insufficient attention of technologist (P=0.001). Other factors like age, hormonal status, breast size and hormone use were not associated with the pain experienced. Thirty-two women (3.3%) indicated that they would not attend further screening, 25 (2.6%) reported that the pain might deter them, six women (0.6%) had other reasons, one woman (0.1%) was sure not to come because of severe pain. In conclusion, a large majority of women attending breast cancer screening describes mammography as painful (72.9%). Factors associated with pain were described. Relatively few women (2.7%) indicated that the pain might deter them from future mammography. Recommendations are given to reduce the pain experienced during screening mammography.     

Phase II of doxorubicin/taxol in metastatic breast cancer

Purpose. To assess the response rate, survival, and toxicity of Taxol®(paclitaxel) as 1h infusion plus doxorubicin as firstline treatment for patients with metastatic breast cancer (MBC).Patients and methods. Seventysix patients with untreated MBC were recruited. All of them had measurable disease and were evaluable for toxicity. Fiftyfive percent of the patients had visceral involvement. The dose of doxorubicin was fixed at 50mg/m² as a short intravenous infusion, followed by 200mg/m² of Taxol as a 1h intravenous infusion. Doxorubicin was administered during the first seven cycles, continuing with Taxol only up to a maximum of ten cycles.Results. Neutropenia was the most important toxicity: 30% grade 3 and 18% grade 4. Only 2 patients showed a decrease in the left ventricular ejection fraction (LVEF) which caused discontinuing the treatment. No clinical congestive heart failure (CHF) was observed. Seventyfour patients were eligible for response evaluation: 10 (14%) achieved complete response (CR) and 46 (62%) achieved partial response (PR). The mean duration of response was 13.47± 1.35 months (95% confidence interval (CI): 10.82; 16.12) and the mean survival was 21.50± 1.42 months (95% CI: 18.72; 24.29).Conclusion. The overall response (OR) rate was 76%. No CHF was assessed and 2 patients stopped treatment due to LVEF decrease. Although doxorubicin 50mg/m² followed by Taxol 200mg/m² in 1h intravenous infusion presents a toxicity profile which demands a close followup, it represents a convenient outpatient schedule with similar activity rate compared to longer Taxol infusions.     

Expression of inducible nitric oxide synthase in human breast cancer depends on tumor grade

Expression of inducible nitric oxide synthase (iNOS) by tumor cells has been suggested to abrogate metastasis in several tumor models, whereas constitutive NOS expression correlated positively with tumor grade in human breast carcinoma. Whether or not expression of one of the various NOS isoforms could predict the prognosis of breast cancer, however, has not been established. In the present report we investigated the cellular distribution of NOS isoforms in a series of benign and malignant breast tumors and in normal breast tissue. Immunohistochemistry revealed that in samples of benign disease the number of iNOS+epithelial cells or total epithelial cells was 69±16% (n=50). In samples of grade II invasive ductal breast carcinomas the number of iNOS+ tumor cells or total tumor cells was 62±20 (n=40), compared to 12±9 (n=40) in samples of grade III carcinomas (P<0.0001). iNOS protein was also identifiable in most of the epithelial cells of normal breast tissue (n=4). In contrast, eNOS protein was restricted to vascular endothelial cells in all of the specimens studied. Since the presence of tumor cell iNOS protein is inversely related to the tumors metastatic potential, we conclude that endogenous tumor cell mediated iNOS expression might have an inhibitory effect on the metastatic process in breast cancer.