An internally and externally validated nomogram for predicting the risk of irinotecan-induced severe neutropenia in advanced colorectal cancer patients.

BACKGROUND: In Asians, the risk of irinotecan-induced severe toxicities is related in part to UGT1A1*6 (UGT, UDP glucuronosyltransferase) and UGT1A1*28, variant alleles that reduce the elimination of SN-38, the active metabolite of irinotecan. We prospectively studied the relation between the UGT1A1 genotype and the safety of irinotecan-based regimens in Japanese patients with advanced colorectal cancer, and then constructed a nomogram for predicting the risk of severe neutropenia in the first treatment cycle. METHODS: Safety data were obtained from 1312 patients monitored during the first 3 cycles of irinotecan-based regimen in a prospective observational study. In development of the nomogram, multivariable logistic regression analysis was used to test the associations of candidate factors to severe neutropenia in the first cycle. The final nomogram based on the results of multivariable analysis was constructed and validated internally using a bootstrapping technique and externally in an independent data set (n=350). RESULTS: The UGT1A1 genotype was confirmed to be associated with increased risks of irinotecan-induced grade 3 or 4 neutropenia and diarrhoea. The final nomogram included type of regimen, administered dose of irinotecan, gender, age, UGT1A1 genotype, Eastern Cooperative Oncology Group performance status, pre-treatment absolute neutrophil count, and total bilirubin level. The model was validated both internally (bootstrap-adjusted concordance index, 0.69) and externally (concordance index, 0.70). CONCLUSIONS: Our nomogram can be used before treatment to accurately predict the probability of irinotecan-induced severe neutropenia in the first cycle of therapy. Additional studies should evaluate the effect of nomogram-guided dosing on efficacy in patients receiving irinotecan.

S-1 as adjuvant chemotherapy for stage III colon cancer: a randomized phase III study (ACTS-CC trial).

BACKGROUND: S-1 is an oral fluoropyrimidine whose antitumor effects have been demonstrated in treating various gastrointestinal cancers, including metastatic colon cancer, when administered as monotherapy or in combination chemotherapy. We conducted a randomized phase III study investigating the efficacy of S-1 as adjuvant chemotherapy for colon cancer by evaluating its noninferiority to tegafur-uracil plus leucovorin (UFT/LV). PATIENTS AND METHODS: Patients aged 20-80 years with curatively resected stage III colon cancer were randomly assigned to receive S-1 (80-120 mg/day on days 1-28 every 42 days; four courses) or UFT/LV (UFT: 300-600 mg/day and LV: 75 mg/day on days 1-28 every 35 days; five courses). The primary end point was disease-free survival (DFS) at 3 years. RESULTS: A total of 1518 patients (758 and 760 in the S-1 and UFT/LV group, respectively) were included in the full analysis set. The 3-year DFS rate was 75.5% and 72.5% in the S-1 and UFT/LV group, respectively. The stratified hazard ratio for DFS in the S-1 group compared with the UFT/LV group was 0.85 (95% confidence interval: 0.70-1.03), demonstrating the noninferiority of S-1 (noninferiority stratified log-rank test, P < 0.001). In the subgroup analysis, no significant interactions were identified between the major baseline characteristics and the treatment groups. CONCLUSION: Adjuvant chemotherapy using S-1 for stage III colon cancer was confirmed to be noninferior in DFS compared with UFT/LV. S-1 could be a new treatment option as adjuvant chemotherapy for colon cancer. CLINICALTRIALSGOV: NCT00660894.

Safety of UFT/LV and S-1 as adjuvant therapy for stage III colon cancer in phase III trial: ACTS-CC trial.

BACKGROUND: The Adjuvant Chemotherapy Trial of TS-1 for Colon Cancer (ACTS-CC) is a phase III trial designed to validate the non-inferiority of S-1 to UFT/leucovorin (LV) as postoperative adjuvant chemotherapy for stage III colon cancer. We report the results of a planned safety analysis. METHODS: Patients aged 20-80 years with curatively resected stage III colon cancer were randomly assigned to receive UFT/LV (UFT, 300 mg m(-2) per day as tegafur; LV, 75 mg per day on days 1-28, every 35 days, 5 courses) or S-1 (80, 100, or 120 mg per day on days 1-28, every 42 days, 4 courses). Treatment status and safety were evaluated. RESULTS: Of 1535 enrolled patients, a total of 1504 (756 allocated to S-1 and 748 to UFT/LV) were analysed. The completion rate of protocol treatment was 77% in the S-1 group and 73% in the UFT/LV group. The overall incidence of adverse events (AEs) were 80% in S-1 and 74% in UFT/LV. Stomatitis, anorexia, hyperpigmentation, and haematological toxicities were common in S-1, whereas increased alanine aminotransferase and aspartate aminotransferase were common in UFT/LV. The incidences of grade 3 AEs were 16% and 14%, respectively. CONCLUSION: Although AE profiles differed between the groups, feasibility of the protocol treatment was good. Both S-1 and UFT/LV could be safely used as adjuvant chemotherapy.

The indications for a diverting stoma in low anterior resection for rectal cancer: a prospective multicentre study of 222 patients from Japanese cancer centers.

AIM: The aim of the study was to determine the present state of diverting stoma construction in Japanese cancer centres and to investigate the relationship between symptomatic leakage and diverting stoma after low anterior resection for rectal cancer. METHOD: Two hundred and twenty-two consecutive patients undergoing low anterior resection for rectal cancer located within 10 cm from the anal verge were investigated in a prospective, multicenter study. RESULTS: The overall leakage rate was 9.0% (20/222). Of 31 cases with an anastomosis within 2.0 cm from the anal verge, 22 (71%) had a diverting stoma. Of cases anastomosed within 5.0 cm, the absence of a diverting stoma and tumour size were significantly related to an increased rate of leakage [leakage in 13 (12.7%) of 102 cases without a diverting stoma; in three (3.8%) of 80 cases with a diverting stoma]. Among anastomoses within 2.0 cm from the anal verge, leakage occurred in four (44.4%) of nine cases without and in none (0%) of 22 cases with a diverting stoma. CONCLUSION: We recommend a diverting stoma for an anastomosis within 5.0 cm of the anal verge and strongly recommend it for a very low anastomosis within 2.0 cm.

Application of immunochemical methods to the identification and characterization of rat kidney inactive renin.

Identification of inactive prorenin in the kidney has been difficult due to rapid proteolytic conversion of the inactive zymogen to its active form in the tissue or during homogenization and purification. Immunochemical methods, Western blotting, direct radioimmunoassay, and immunoaffinity chromatography were used to isolate and identify rat kidney renin and prorenin and to determine their molecular weights without complete purification. Antisera to pure rat renin were raised in rabbits. A specific reaction between the antisera and rat renin was demonstrated by double immunodiffusion, inhibition of enzyme activity, and competitive radioimmunoassay. The anti-rat renin IgG did not cross-react with purified human renin or rat spleen or kidney cathepsin D. The IgG showed binding affinity to both inactive renin as well as active enzyme. A combination of affinity chromatographies consisting of pepstatin-Sepharose, IgG-Sepharose, and Affi-Gel Blue permitted rapid and complete separation of inactive renin from active renin in rat kidney extract. Neither inactive nor active renin preparations exhibited aspartyl protease activity on hemoglobin used as substrate. The apparent molecular weight of inactive renin was estimated as 50,000 by gel filtration. Electrophoresis of partially purified inactive renin in sodium dodecyl sulfate (SDS) polyacrylamide gel followed by transblotting of proteins to a nitrocellulose sheet and immunochemical staining with anti-renin IgG showed a single protein band with a molecular weight of 48,000. Activation of inactive renin by trypsin was accompanied by the reduction of the 48,000-dalton native protein to a 39,000-dalton protein as determined by the SDS polyacrylamide gel electrophoresis and the transblotting.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunohistochemical evidence that angiotensins I and II are formed by intracellular mechanism in juxtaglomerular cells.

The existence of angiotensin II (AII) immunoreactivity in juxtaglomerular (JG) cells of rat kidney, which has been demonstrated previously by immunohistochemical studies, can be explained either as the product of intracellular synthesis or by the internalization of receptor-bound AII originating in plasma. To resolve these two alternative mechanisms, attempts were made to identify AI in JG cells of rat kidney by immunohistochemical staining using specific antibodies to AI. Although AI-like immunoreactivity was not detected in normal rat kidney, rats treated with the angiotensin-converting enzyme inhibitors, MK-421 or captopril, showed AI-like immunoreactivity in JG cells. The presence of renin and AII-like immunoreactivity was demonstrated in the same cells by specific antibodies to respective antigens used on adjacent serial sections. These findings support an intracellular mechanism of the formation of AII and suggest an intracellular renin angiotensin system, presumably separate from the extracellular system.

Hyperplasia of juxtaglomerular cells and renin localization in kidney of normotensive animals given captopril. Electron microscopic and immunohistochemical studies.

Captopril, a competitive inhibitor of angiotensin I-converting enzyme (ACE), is an orally potent antihypertensive agent. Light and electron microscopic studies of th kidneys of mice, rats, and monkeys given large oral doses of captopril for long duration were conducted. All mice and some rats and monkeys developed hyperplasia of the renin-secreting cells which appeared in several layers surrounding the vascular wall of the afferent arterioles. In the electron microscope, these epithelioid cells appeared heavily loaded with aggregates of homogeneous electron dense, osmiophilic amorphous granules filling distended spaces of the endoplasmic reticulum. The Golgi cisterns often included small, sharply outlined triangular or rhomboid osmiophilic granules. The use of specific renin antibodies and the application of the "three-layer bridge technique" for peroxidase-antiperoxidase defined and verified the accumulation of renin in the juxtaglomerular cells. After cessation of dosing, hyperplasia of the juxtaglomerular cells markedly regressed, and there was a significant reduction in the number and size of the renin granules in such cells.

Partial purification of prorenin and activation by kallikreins: a possible new link between renin and kallikrein systems.

With the objective of identifying prorenin and its physiological activation mechanism, human plasma prorenin was completely separated from active renin for the first time. It was shown that prorenin has no activity whereas active renin has no potential for further activation. Urinary kallikreins were found to activate prorenin fractions freed from kallikrein inhibitors by affinity chromatography and treatment at pH 3.3. Human plasma kallikrein also exhibited weak activation.

Enzymic formation of thiamine pyrophosphate in plants.

Evidence was presented by paper chromatographic analysis on the occurrence of an enzyme capable of catalyzing a pyrophosphate transfer from ATP to thiamine in green leaves of various plants. The exclusive localization of the enzyme activity in the 105,000 X g supernatant (in a soluble form) was demonstrated by differential centrifugation of a cell homogentae in 0.25 M sucrose. The enzyme was purified by column chromatography with DEAE-cellulose and by gel filtration with Sephadex G-150. The partially pruified preparation, while contaminated with detectable activity of acid phosphatase, lost the ability of utilizing thiamine monophosphate as the substrate in place of thiamine. These findings lead to the conclusion that thiamine pyrophosphate is formed in green leaves of plants through a direct pyrophosphorylation of thiamine in the presence of ATP and Mg.

Mechanism and regulation of thiamine pyrophosphokinase from parsely leaf.

Thiamine pyrophosphokinase (EC 2.7.6.2) from parsely leaf showed an absolute requirement for divalent cation such as Mg2+, Mn2+ and Co2+. The activation effect varied with the species and concentrations of such cations. When Mn2+ or Co2+ was used as cofactor, maximal activation was found at a lower level than ATP concentration, whereas the activation by Mg2+ increased hyperbolically with the concentration. Studies of initial velocity and product inhibition led to conclude that the kinase reaction obeys a sequential ordered Bi Bi mechanism; i.e. the enzyme combines in turns with MgATP and thiamine, followed by release of TPP and AMP. The inhibition type revealed for inorganic pyrophosphate was competitive with respect to thiamine with Ki of approximately 2.8 mM. On the other hand, thiamine monophosphate exhibited noncompetitive inhibition with Ki of 0.2 mM. The plots of the reaction rate against MgATP concentrations gave a sigmoidal curve. Addition of either AMP or GMP resulted in restoration of a depressed activity at low concentration of MgATP. The "allosteric" inhibition was also relieved by the addition of an excess amount of magnesium ions. These findings suggest that transphosphorylation is regulated by subcellular concentrations of metal ions relative to ATP or of the products involved in the thiamine biosynthesis.

Purification and properties of thiamine pyrophosphokinase from parsely leaf.

Thiamine pyrophosphokinase was purified about 8,000-fold from extracts of parsely leaves. The enzyme, as prepared, was homogenous on polyacrylamide gel electrophoresis. The molecular weight of the enzyme, estimated by gel filtration with Sephadex G-150, was approximately 30,000. In 0.05 M Tris-HCl, the enzymic activity showed a pH optimum over a range of 8 to 9. A least squares analyses of Lineweaver-Burk and Hofstee plots gave Km values of 0.8mM and 0.15mum for ATP and thiamine, respectively. Thiamine homologues and analogues so far tested, except for cetyl thiamine, were all inactive as substrates. The enzyme was specific for ATP and Mg++, although to a lesser extent a combination with other ribonucleoside triphosphates or divalent cations could replace them. SH reagents, such as PCMB, NEM and iodoacetamide, were potent inhibitors of the enzyme. The inhibition was prevented by the addition of dithiothreitol. Inorganic pyrophosphate exhibited striking inhibition. TMP could not replace thiamine as the substrate, whereas it inhibited the TPP formation from thiamine. These findings are consistent with the views that TMP is not directly converted to TPP but after being dephosphorylated by the action of a monoesterase, thiamine is pyrophosphorylated with ATP by thiamine pyrophosphokinase (EC 2.7.6.2) to form TPP and thus give a clear evidence regarding the mechanism of TPP formation in plant tissues.

[A T-cell type non-Hodgkin's lymphoma with a near-triploid karyotype].

A 16 year-old boy of non-Hodgkin's lymphoma (NHL) was reported. Although Hodgkin's disease was suspected by the presence of Reed-Sternberg-like cells and lacunar cells histologically, a diagnosis of NHL was made because of atypism and monoclonality of the background's cells as well as the morphology of invasive cells in the bone marrow. The tumor cells expressed, CD2, CD3, CD4, CD5 and CD7 antigens, which corresponded to the phenotype of helper-inducer T-lymphocytes. In the analysis of their karyotypes, 16 out of 24 cells revealed normal karyotype, while all the rest showed near-triploidy. Common abnormality was identified as trisomies of No. 1, 3, 5, 16, 21 chromosomes, tetrasomies of No. 10, 19, 20 chromosomes, and 4q+, 7q+, 14p+. Multimodal chemotherapy was successful to induce the patient promptly into complete remission. He has been free from the disease for approximately 12 months. Thus far, triploid clones in hematopoietic malignancies have rarely been described. More importantly, the appearance of them in pediatric lymphoid neoplasms has not yet been reported.

[A patient with advanced gastric cancer who obtained downstaging and underwent radical surgery by neoadjuvant chemotherapy].

The patient was a 74-year-old man with extremely advanced gastric cancer. A CT scan of the abdomen showed enlargement of many huge abdominal para-aortic lymph nodes. Neoadjuvant chemotherapy (NAC) was planned in order to reduce or eliminate the tumor. Two cycles of FLP combination therapy (5-fluorouracil, leucovorin, cisplatin) were given. After NAC, a CT scan revealed marked shrinkage of the No. 16 lymph nodes, and a distal gastrectomy with extended radical lymph node dissection including the No. 16 nodes was performed. The histological effect was judged to be grade 2. There were no viable cancer cells in the No. 16 lymph nodes. The FLP combination therapy as NAC was so effective that it induced downstaging from stage IVb to IIIb.

[Proctocolectomy with ileal W pouch anal anastomosis for ulcerative colitis].

Restorative proctocolectomy with ileal pouch anal anastomosis, which is a relatively new procedure, has become a standard procedure for ulcerative colitis (UC) requiring surgical management. The main impact of this procedure is to cure patients of disease and to avoid permanent ileostomy, preserving better defecatory function and acceptable QOL. Some key aspects of our surgical procedure are as follows: 1) two or three separate staged operation, 2) W-shaped reservoir, 3) distal rectal mucosectomy and handsewn ileo-anal anastomosis, 4) short muscular cuff, and 5) temporary diverting ileostomy. Staged operation and diverting ileostomy are helpful to decrease risk of pelvic infection. Total removal of the rectal mucosa is necessary to cure the disease, and shorter muscular cuff decreases operating time and bleeding and thus the risk of pelvic sepsis. The W-shaped reservoir described by Nicholls brings both spontaneous defecation and improved function. We have adopted ileal W-pouch among several types of reservoir to 58 patients with UC since 1984, and found that a large and wide reservoir might allow better defecatory function. There were no cases of serious complications and no needs to remove the reservoir. Mean daily stool frequency was gradually decreased with time, and 4.9 stools per 24 hours at present day, and clinical score of neorectal function also gradually improved according to reduction of stool frequency. Seventy three percent of patients felt their defecatory function satisfactory and 89% of the patients recovered acceptable QOL no less than that obtained during the medically treated period.

Immunohistochemical localization of renin in luteinizing hormone-producing cells of rat pituitary.

The location of renin (EC 3.4.99.19) in rat pituitary was determined by the peroxidase-antiperoxidase immunohistochemical technique. By using antisera prepared with purified rat renal renin, an immunoreactive substance was localized within ovoid cells scattered throughout the anterior pituitary. These cells were shown to be luteinizing hormone-producing cells by staining with anti-luteinizing hormone antisera in adjacent sections. By using the double staining method, the renin-containing cells were differentiated from cells containing corticotropin, thyrotropin, growth hormone (somatotropin), and prolactin (mammotropin). These results suggest a possible local role for renin in the anterior pituitary.

Cloning and expression of a thermostable exo-alpha-1,4-glucosidase gene from Bacillus stearothermophilus ATCC12016 in Escherichia coli.

The gene coding for a thermostable exo-alpha-1,4-glucosidase (alpha-glucoside glucohydrolase: EC 3.2.1.20) of Bacillus stearothermophilus ATCC 12016 was cloned within a 2.8-kb AvaI fragment of DNA using the plasmid pUC19 as a vector and Escherichia coli JM109 as a host. E. coli with the hybrid plasmid accumulated exo-alpha-1,4-glucosidase mainly in the cytoplasm. The level of enzyme production was about sevenfold higher than that observed for B. stearothermophilus. The cloned enzyme coincided absolutely with the B. stearothermophilus enzyme in its relative molecular mass (62,000), isoelectric point (5.0), amino-terminal sequence of 15 residues (Met-Lys-Lys-Thr-Trp-Trp-Lys-Glu-Gly-Val-Ala-Tyr-Gln-Ile-Tyr-), the temperature dependency of its activity and stability, and its antigenic determinants.