Keiji Koda

Quantitative Measurement of Blood Flow Using Perfusion CT for Assessing Clinicopathologic Features and Prognosis in Patients with Rectal Cancer

PURPOSE: The ability to evaluate clinicopathologic features and prognosis before surgery by contrast-enhanced CT would be valuable for managing rectal cancer. This study was designed to evaluate the clinical usefulness of perfusion CT in patients with rectal cancer before surgery. METHODS: Forty-four consecutive patients (27 men, 17 women; median age, 63.6 years) with rectal cancer underwent perfusion CT before surgery. We retrospectively investigated the correlations between tumor blood flow generated by perfusion CT and clinicopathologic features. RESULTS: There was a significant correlation between blood flow and wall invasion (P = 0.04). Well-differentiated tumors showed significantly higher blood flow than moderately differentiated tumors (P = 0.03). There was a significant tendency for tumors with low blood flow to show lymph node metastasis (P = 0.0005), vascular invasion (P = 0.004), lymphatic invasion (P = 0.04), and distant metastasis (P = 0.0005). For blood flow, accuracy was 75% for detection of tumors with lymph node metastasis if the cutoff point was set at 55 ml/100 g per minute. Patients with high blood flow tumors survived significantly longer than those with low blood flow tumors (P = 0.002). CONCLUSIONS: Blood flow of rectal cancers may be useful to evaluate pathologic features and prognosis before surgery.

Denervation of the neorectum as a potential cause of defecatory disorder following low anterior resection for rectal cancer

PURPOSEThe aim of this study was to determine whether denervation of the sigmoid colon during low anterior resection contributes to the postoperative motility characteristics of the neorectum and to the defecatory function of patients.METHODSSixty-seven patients who underwent either low or ultralow anterior resection for rectal cancer were evaluated. In accordance with the length of denervated neorectum, each patient was assigned to either the short-denervation or long-denervation group, determined by whether the inferior mesenteric artery was divided. Colonic propagated contraction was then measured by means of intraluminal pressure monitoring. Transit time was calculated with orally administered radiopaque markers.RESULTSPropagated contraction down to the neorectum was significantly less common in the long-denervation group (14/36) than in the short group (12/15, P < 0.05), whereas spastic minor contraction at the neorectum was significantly more common in the long-denervation group (21/36) than the in short group (3/15, P < 0.05). Colonic transit time below the sigmoid colon was significantly longer in long group (6.4 hours) than in the short group (3.4 hours, P < 0.01). Although motility disorder of the neorectum was correlated with clinical defecatory malfunctions, including multiple evacuations, urgency, and soiling, no significant correlation was noted between the length of the denervated neorectum and the defecatory disorders.CONCLUSIONSMotility of the neorectum following low anterior resection appears degraded by intraoperative maneuvers that cause denervation of the remnant sigmoid colon. Motility disorder of the neorectum, but not the length of the denervated neorectum causing the disorder, correlates well with several defecatory malfunctions. This finding suggests that postoperative defecatory disorder as a result of low anterior resection is caused by many factors in addition to denervation of the neorectum.

Sonic hedgehog-Gli1 signaling pathway might become an effective therapeutic target in gastrointestinal neuroendocrine carcinomas

Gastrointestinal neuroendocrine carcinomas (NECs) are extremely aggressive and poorly prognostic. We showed previously that human achaete-scute homologue gene 1 (hASH1), a basic helix-loop-helix transcription factor regulated by Notch, was aberrantly expressed in NECs. To date, no effective therapeutic strategies for NECs have been investigated. Notch, Wnt and Hedgehog (Hh) signalings are important for stem cell self-renewal and carcinogenesis in the gastrointestinal epithelium. In this study, we showed that Hh signaling was clearly upregulated in NECs in Gli1-dependent manner. Specific therapeutic effects of cyclopamine on NECs were also demonstrated. RT-PCR showed that among eight frozen samples (three NECs, one carcinoid tumor, three adenocarcinomas and one normal mucosa), the band intensities of Gli1 were the strongest in NECs, moderately strong in a carcinoid tumor, very weak in adenocarcinomas and undetectable in a normal mucosa. In real-time RT-PCR, the expression levels of Gli1 in NECs were 108.4, 28.6 and 16.3 times higher than that in an adenocarcinoma. In immunohistochemistry using 25 paraffin-embedded tissues, all twelve NECs and three of six carcinoid tumors showed positive stainings for Gli1, whereas six of seven adenocarcinomas were negative. In vitro, RT-PCR showed that NEC cell lines expressed Gli1 mRNA significantly. Administration of cyclopamine suppressed cell proliferation and invasion, and induced apoptosis in NECs. In cyclopamine-treated NECs, downregulation of Gli1, Ptch1, Snail and hASH1, and upregulation of E-cadherin were demonstrated at mRNA levels. Such effects were not observed in a Gli1-negative colonic adenocarcinoma cell line or in control alkaloid-treated NECs. Hh signaling may play a crucial role in the pathophysiology of NECs. Blockade of Hh pathway using cyclopamine or its synthetic derivatives might open an effective therapeutic strategy to NECs, not only by suppressing tumor viability but also by altering tumor cell nature.

The nature of an ideal therapeutic human antibody

With all the advancements in recombinant DNA technology virtually any antibody molecule can be designed; either engineered or reverse engineered [1,2]. Shuffling and rearranging antibody genes and gene segments can now be accomplished so the entire antibody molecule can be completely created. Phage display libraries also provide an exhaustive palette from which to build antibody molecules. In reverse engineering antibodies, instead of commonly starting with an antibody, one begins with an antigen and builds an antibody molecule around it. Either way the antibody molecule can be designed to achieve specific goals and what those goals are will determine what type of antibody should be designed. Since the technology is now available to perform all this engineering, the focus then shifts to what type of antibody is required and for what purposes. In the field of oncology, the optimal criterion in designing the best type of antibody can be identified. Optimisation should help ensure more efficacious treatments. Thus, an examination of what would make an ideal antibody is in order. An ideal anticancer human antibody would have:

Serotonin (5-HT3) receptor antagonists for the reduction of symptoms of low anterior resection syndrome

Purpose Serotonin (5-hydroxytryptamine [5-HT])3 receptor antagonists are effective for the treatment of diarrhea-predominant irritable bowel syndrome (IBS-D), in which exaggerated intestinal/colonic hypermotility is often observed. Recent studies have suggested that the motility disorder, especially spastic hypermotility, seen in the neorectum following sphincter-preserving operations for rectal cancer may be the basis of the postoperative defecatory malfunction seen in these patients. We investigated the efficacy of 5-HT3 receptor antagonists in patients suffering from severe low anterior resection syndrome. Patients and methods A total of 25 male patients with complaints of uncontrollable urgency or fecal incontinence following sphincter-preserving operations were enrolled in this study. Defecatory status, assessed on the basis of incontinence score (0–20), urgency grade (0–3), and number of toilet visits per day, was evaluated using a questionnaire before and 1 month after the administration of the 5-HT3 antagonist ramosetron. Results All the parameters assessed improved significantly after taking ramosetron for 1 month. The effect was more prominent in cases whose anastomotic line was lower, ie, inside the anal canal. Defecatory function was better in patients who commenced ramosetron therapy within 6 months postoperatively, as compared to those who were not prescribed ramosetron for more than 7 months postoperatively. Conclusion These results suggest that 5-HT3 antagonists are effective for the treatment of low anterior resection syndrome, as in diarrhea-predominant irritable bowel syndrome. The improvement in symptoms is not merely time dependent, but it is related to treatment with 5-HT3 antagonists.

Tumor-associated antigens recognized by human monoclonal antibodies

AbstractBackground: Nonhuman monoclonal antibodies (MoAbs) of desired specificities have been studied in cancer treatment and tumor targeting with minimal success. Attempts of using humanized chimeric antibodies have not improved significantly their clinical applications. We have engaged in the development of human MoAbs by incorporating the in vitro immunization protocols to the nodal lymphocytes of cancer patients. Three human MoAbs thus generated were found to be strongly reactive with various human malignancies. The antigens recognized by the three antibodies were selected for immunochemical and biochemical characterizations. Methods: The antigens investigated were AgSK1, PA 1-2 and PA 3-1. The patterns of each antigen expression in various human cancer cell lines were studied by the immunocytochemical staining technique. The expression of AgSK1 in association with cellular proliferation was examined by the flow cytometry analysis. In studying the biochemical natures of these antigens, their sensitivies toward various chemical and physical treatments were determined. The antigens that were shown to be proteins were subjected to SDS-PAGE and Western blot for estimations of molecular weights. Results: The AgSK1 was detected in 10 human carcinoma cell lines but in none of the melanoma cell lines. This suggests that SK1 may be an epithelial or carcinoma marker. The phenotypic expressions of AgSK1 were shown to be associated with proliferation of carcinoma cells. Biochemically AgSK1 was a sialophycoprotein with an estimated molecular weight of 42–44 kilodaltons (kDa). HuMAb PA1-2 demonstrated a unique staining pattern at both the cytoplasmic and intercellular interface. The stained filamentlike structures extending from cell to cell indicated that Ag PA1-2 might play a role in cellular interactions. Biochemically, Ag PA1-2 appeared to be an asialocarbohydrate. The Ag PA3-1 was a cytoplasmic glycoprotein expressed by all 13 cell lines. The estimated molecular weights of PA3-1 were 164, 104, and 40 kDa. Conclusions: Tumor-associated antigens recognized by the human MoAbs may be more relevant clinically than those recognized by the mouse immune system. Carcinoma-specific human MoAbs are desirable for cancer treatment and tumor localization.

Gas volume analysis and postoperative bowel functional disorders in patients who received anterior resection for rectal cancer.

AbstractPURPOSE: Colon gas analysis using abdominal radiography has been reported as a reliable method for assessing functional bowel disorders. The aim of this study was to clarify the relevance of colon gas distribution in postoperative disorders such as constipation and feelings of incomplete evacuation following rectal cancer operation. METHODS: Colon gas volume score was calculated using plain abdominal radiographs and evaluated in 50 patients who had received low anterior resections. Twenty-one constipated patients who required laxatives and 29 patients who did not were compared in terms of colon gas distribution. In addition, 32 patients with postoperative feelings of incomplete evacuation and 18 patients without such feelings were assessed in similar fashion. RESULTS: Left colon gas scores in patients who required laxatives were significantly higher (2.82 ± 3.23 percent) than in nonusers (1.21 ± 0.96 percent; P < 0.01). Patients with feelings of incomplete evacuation displayed significantly higher left side colon gas scores (2.51 ± 2.66 percent) than those without such feelings (0.77 ± 0.81 percent; P < 0.0001). CONCLUSION: Patients with postoperative functional bowel disorders such as constipation or feelings of incomplete evacuation may experience relatively high volumes of gas in the left colon.

Human monoclonal antibodies to nuclear antigens

Human lymph node lymphocytes from cancer patients were fused with either the UC 729-6 or SHFP-1 human fusion partners. Resulting human-human hybridomas were tetraploid, expressed markers from both parent cells, and secreted approximately 1 microgram Ig/10(6) cells/ml/day. Immunofluorescence analysis of some of the human MAbs with a panel of normal and malignant cell lines revealed a staining pattern of only the nuclear region. One IgM secreting hybridoma, TLN1F4, derived from a teratocarcinoma lymph node, predominantly stained the nuclear regions of adherent tumor cell lines and no hematopoietic cell lines or normal fibroblasts. PLN3C8, an IgG1 secreting hybridoma, derived from a prostate carcinoma lymph node, predominantly stained the nucleolus of LnCap, a a carcinoma of the prostate cell line. CLN2E5, an IgM secreting human hybridoma, derived from a carcinoma of the cervix lymph node, predominantly stained both cytoplasmic and nuclear components to tumor cell lines and not normal fibroblasts or hematopoietic cell lines. These data suggest that the immune response occurring within regional draining lymph nodes is capable of recognizing nuclear-associated antigens.

Use of severe combined immunodeficient (SCID) mice to produce human hybridoma ascites

The use of the severe combined immunodeficient mouse (SCID), CB-17/Icr//Imd-SCID, was investigated for the production of human hybridoma ascites containing human antibody. Human-human hybridomas, generated from the fusion of lymphocytes isolated from regional draining lymph nodes of cancer patients with the SHFP-1 fusion partner, were injected i.p. at various cell concentrations into pristane-primed SCID mice. Ascites growth was typically observed at 7-14 days postinoculation. No significant differences in ascites yield or production were observed between IgG- and IgM-secreting hybridomas. Yields of immunoreactive human immunoglobulin ranged from approximately 0.5 to 3 mg/ml of harvested ascites. The ease and relatively low cost suggest that the use of SCID mice is preferred over conventional and costly large-scale industrial procedures.

Dihydropyrimidine dehydrogenase-related enzymes predict efficacy and adverse reactions of UFT1+cisplatin neoadjuvant chemotherapy for gastric cancer.

Dihydropyrimidine dehydrogenase (DPD) and dihydropyrimidinase (DHP) are metabolic enzymes of fluoropyrimidine. UFT containing uracil (U) and Tegafur is the first reported DPD-inhibitory fluoropyrimidine. To clarify the significance of the enzyme activities, we examined the relationships between the effects and adverse reactions, and DPD and DHP activities in gastric cancer treated with UFT1+cisplatin neoadjuvant chemotherapy. Twenty-five gastric cancer patients were administered UFT at 370 mg/m2/day for 21 days and cisplatin at 15 mg/m2/day for 2 days. Dihydrouracil (DU) and U levels in the urine and DPD activities in the resected tumors were measured. Chemotherapeutic effects were classified histologically into non-responder and responder groups. The responder group accounted for 48% of the patients. All six patients with high DPD activities (≥0.08 nmol/min/ww) belonged to the non-responder group and 11 of 19 patients with low DPD activities (<0.08 nmol/min/ww) belonged to the responder group; the difference was significant (p =0.0435). Adverse reactions to UFT occurred in four patients, all of whom were among the six patients with abnormal DU/U values. The incidence of UFT adverse reactions was estimated at 67%. In conclusion, the measured levels of DPD-related enzyme activities appear to be significant for predicting the effects and adverse reactions to chemotherapy.