Intratumoral induction of thymidylate synthase mRNA by 5-FU in colorectal cancer patients: association with survival

Dihydropyrimidine dehydrogenase (DPD) is the rate-limiting enzyme in 5-fluorouracil (5-FU) catabolism. Thymidylate synthase (TS) is inhibited to form an inactive ternary complex by 5-fluoro-dUMP and is considered to be a target enzyme of 5-FU treatment. Two enzymes, DPD and TS, have been reported to be major determinants of individual sensitivity to 5-FU, and it has been reported that TS mRNA levels are modified by 5-FU treatment. We investigated their impact on treatment efficacy in colorectal cancer patients. TS and DPD mRNA levels, which correlated to the corresponding enzyme activities, were quantified in tumor tissues before and after treatment in 40 advanced colorectal cancer patients who had been treated with Doxifluridine (5'-DFUR) for 14 days before surgery. Furthermore inter-individual variations of TS mRNA levels after 5-FU treatment were found, and the individual TS induction varied between patients (0.2-2.4). Increased TS mRNA levels were found in 19 out of 40 cases. The samples were divided into two groups according to their TS mRNA induction (< or >1; TS/beta-actin ratio after treatment divided by values prior treatment) and compared with tumor reduction and survival. TS and DPD mRNA levels in tumor biopsies before treatment were not related to 5-FU responses by histological evaluations in this study. However the efficacy of 5-FU treatment was enhanced in patients with no or low TS mRNA induction (odds ratio: 6.2, p<0.05). Furthermore, longer periods of survival were observed in the group without increased TS mRNA levels. These findings suggest that TS mRNA was induced by 5-FU treatment, and the overall induction level varied between individuals. Therefore, the estimation of TS mRNA induction may be useful to predict the efficacy of 5-FU treatment.     

Association of GSTM1, CYP1A1 and CYP2E1 genetic polymorphisms with susceptibility to lung adenocarcinoma: a case-control study in Chinese population

A case-control study of 164 lung adenocarcinoma (AC) patients with 181 age- and gender-matched healthy controls was conducted in order to assess any associations between glutathione- S -transferase M1 (GSTM1), cytochrome P4501A1 (CYP1A1) and cyto-chrome P4502E1 (CYP2E1) polymorphisms and susceptibility to lung AC in Chinese. The presence of CYP2E1 variant allele was significantly less frequent in cases than in controls, while the distribution of GSTM1 null genotype and variant CYP1A1 Msp 1 allele did not vary between cases and controls. After adjustment for age, gender, smoking and all other genotypes, the CYP2E1 Rsa1 variant allele was significantly associated with decreased risk of lung AC [odds ratio 0.534 (95% confidence interval, 0.340–0.837)]. Furthermore, 3.0-fold increased risk was found in individuals with combined GSTM1 null genotype and CYP2E1 Rsa 1 wild type versus those with combined GSTM1 non-null type and CYP2E1 variant allele. Our results suggest that CYP2E1 Rsa 1 variant allele is associated with a decreased risk of lung AC, and combined GSTM1 null genotype and CYP2E1 Rsa1 wild type has a promoting effect on susceptibility to lung AC. (Cancer Sci 2003; 94: 448–452)     

Relationship of third molar development and root angulation

Angled roots are seen in mandibular third molars, which have a high frequency of incomplete impaction. We examined the relationship between incomplete impaction and angled roots. We enrolled orthopantomographs to determine the prevalence of angled roots in 239 men and 222 women aged 21--35 years with bilateral mandibular third molars. Angled roots were more frequent in subjects in whom the third molars had a different status on each side than in those with the same status on both sides (men: P<0.05; women: P<0.01). The incidence of women with angled roots in those with bilateral incomplete impactions was higher than that in those with bilateral eruption (P<0.01). Angled roots among mandibular third molars are related to environmental factors. Angled roots occur more frequently in women with incomplete impaction than in those with full eruption.     

Plasma concentrations of (n-3) highly unsaturated fatty acids are good biomarkers of relative dietary fatty acid intakes: a cross-sectional study

A cross-sectional study was conducted to clarify the associations of lifestyle factors (habitual exercise, alcohol intake and smoking habit) and plasma fatty acid (FA) concentrations as biomarkers of dietary FA intakes. We collected 7-d weighed diet records, lifestyle information and blood samples from 15 male and 79 female Japanese dietitians, and estimated dietary FA intakes and analyzed plasma FA concentrations. Plasma concentrations of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and (n-3) highly unsaturated FA (HUFA) derived from marine foods, but not linoleic and alpha-linolenic acid from plant origins, demonstrated positive correlations with dietary intakes (r = 0.303-0.602, P < 0.05) in both genders. Multiple linear regression analyses adjusted for age, BMI, total energy intake, fat (or respective FA) consumption and lifestyle factors showed that dietary intakes of EPA, DHA and (n-3) HUFA were positively associated with age in men (P < 0.05) and negatively associated with BMI in women [P < 0.01 for DHA and (n-3) HUFA]. The plasma concentrations of EPA, DHA and (n-3) HUFA in women were found to be positively associated with age and marine oil (or respective FA) intake (P < 0.01), and negatively associated with total energy intake [P < 0.05 for EPA and (n-3) HUFA]. Lifestyle factors were not associated with dietary FA intakes and plasma FA concentrations. These findings suggest that the plasma concentrations of EPA, DHA and (n-3) HUFA might be useful biomarkers for the assessment of relative FA intakes without considering associations with habitual exercise, alcohol intake and smoking habit.     

Ocular attacks after phacoemulsification and intraocular lens implantation in patients with Behçet disease

PURPOSE: To elucidate factors related to ocular inflammatory attacks after cataract surgery, limited to a single procedure of phacoemulsification and intraocular lens implantation, in patients with Beh?et disease. METHODS: This retrospective study included 12 consecutive patients (16 eyes) with Beh?et disease, who underwent phacoemulsification and intraocular lens implantation during 4 years from January 1995 to December 1998 at three institutions. Their medical records were reviewed, and factors related to the ocular attacks were analyzed. RESULTS: Four eyes of 3 patients experienced ocular attacks during 1 year before cataract surgery, while 4 eyes of 4 patients developed ocular attacks during 1 year after the surgery. The development of ocular attacks after cataract surgery was significantly related with the presence of ocular attacks during 1 year before the surgery (p = 0.0286, chi(2) test). The patients' age or gender, the duration of Beh?et disease or oral medications for Beh?et disease did not show any relationship with the presence or absence of ocular attacks after cataract surgery. The visual acuity improved in all patients after the surgery, including those who developed ocular attacks. CONCLUSIONS: The experience of ocular attacks during 1 year before cataract surgery is related to postoperative ocular attacks. Despite postoperative ocular attacks, phacoemulsification with intraocular lens implantation is a safe procedure to expect a good visual outcome in patients with Beh?et disease.     

Transport characteristics of ebastine and its metabolites across human intestinal epithelial Caco-2 cell monolayers

The transport characteristics of a selective peripheral H1 receptor antagonist, ebastine, a substrate for cytochrome P450 3A4, and its three major metabolites, i.e., the hydroxy metabolite of ebastine (M-OH), the pharmacologically active metabolite carebastine (Car), and the desbutyrophenone metabolite (des-BP), were studied in cultured human intestinal Caco-2 cells expressing a drug efflux pump, P-glycoprotein (P-gp), on the apical membrane. The polarized transport of [3H]cyclosporin A (CyA), mediated by P-gp in the basolateral to apical direction across the Caco-2 cell monolayers, was affected by the presence of ebastine in a concentration-dependent manner and significant inhibition was observed at high concentrations (>50 microM). M-OH (300 microM) also significantly inhibited whereas Car and des-BP did not. Although no marked polarized transport of [14C]ebastine in a secretory direction was observed in the Caco-2 systems, the flux in the basolateral to apical direction was slightly higher than that in the opposite direction at concentrations less than 30 microm. [14C]Ebastine (2 microM) uptake from the apical side was significantly increased in the presence of an excess of cold CyA, suggesting that the efflux process mediated by P-gp may be involved in the ebastine uptake by Caco-2 cells. Collectively, these results indicate that ebastine (and presumably M-OH) is transported via P-gp in Caco-2 cells, however, the affinity for P-gp is very low. It is unlikely that the secretory transport of ebastine mediated by P-gp will dramatically affect overall intestinal absorption in vivo because efficient passive diffusion of this drug should occur due to its high lipophilicity. However, it may be advantageous for its efficient first-pass metabolism.     

In situ pedicle resection in left trisegmentectomy of the liver combined with reconstruction of the right hepatic vein to an inferior vena caval segment transpositioned from the infrahepatic portion

A combination of an in situ pedicle resection of the liver and a hepatic vein reconstruction using a cranially transpositioned segment of the IVC after implantation of an ePTFE graft at the missing IVC was useful in treating a patient who suffered from a huge liver tumor involving all of the hepatic venous confluence and the IVC. Although early tumor recurrence remains an unresolved problem for such patients, a surgical approach is feasible. This technique can be justified as a therapeutic modality, not only because it improves quality of life, but also because it provides patients with an opportunity for additional treatment.     

Genetic instability did not lead to p53 mutations in an extremely early-onset breast cancer in a cancer-prone family.

BACKGROUND: A positive family history is a major contributor to risk of development of breast cancer. METHODS: Somatic and germ line mutations of p53 and genetic instability were evaluated for an extremely early-onset breast cancer case in a cancer-prone family. RESULTS: The mode of inheritance in this case was clearly autosomal dominant. DNA replication error was recognized by detecting microsatellite allelic alterations. However, mutations of p53 were not found at either somatic or germ-line level. CONCLUSION: These genetic studies suggest that an increased genetic instability did not lead to p53 gene mutations in this breast cancer patient.     

Uptake and Intracellular Distribution of Amrubicin, a Novel 9-Amino-anthracycline, and Its Active Metabolite Amrubicinol in P388 Murine Leukemia Cells

Amrubicin, a 9-aminoanthracycline anti-cancer drug, and its C-13 hydroxyl metabolite amrubicinol, were examined for growth-inhibitory activity as well as cellular uptake and distribution in P388 murine leukemia cells and doxorubicin-resistant P388 cells. Also discussed are the differences in the mechanisms of action among amrubicin, amrubicinol and doxorubicin in terms of their cellular pharmacokinetic character. In P388 cells, amrubicinol was about 80 times as potent as amrubicin, and about 2 times more potent than doxorubicin in a 1-h drug exposure growth-inhibition test. A clear cross-resistance was observed to both amrubicin and amrubicinol in doxorubicin-resistant P388 cells, though the resistance index was lower for amrubicin. The intracellular concentration of amrubicinol was about 6 times and 2 times higher than those of amrubicin and doxorubicin, respectively. Compared to doxorubicin, amrubicin and amrubicinol were released rapidly after removal of the drugs from the medium. A clear correlation was found between the growth-inhibiting activity and the cellular level of amrubicin and amrubicinol in P388 cells. About 10 to 20% of amrubicin or amrubicinol taken up by the cells was detected in the cell nuclear fraction, whereas 70 to 80% of doxorubicin was localized in this fraction. These results suggest that amrubicin and amrubicinol exert cytotoxic activity via a different mechanism from that of doxorubicin.