Sulindac effects on inflammation and tumorigenesis in the intestine of mice with Apc and Mlh1 mutations.

We have previously reported that sulindac, a non-steroidal anti-inflammatory drug, inhibited tumor formation in the small intestine but increased tumors in the colon of Apc(Min/+) mice, a model of human familial adenomatous polyposis. To further explore intestinal regional responses, we studied effects of sulindac on additional gene-targeted mouse models of human intestinal tumorigenesis; these were (i) Apc(1638N/+) mouse (chain termination mutation in exon 15 of the Apc gene); (ii) Mlh1(+/-) mouse (DNA mismatch repair deficiency, a mouse model of human hereditary non-polyposis colorectal cancer) and (iii) double-heterozygous Mlh1(+/-)Apc(1638N/+) mutant mouse. Mice were fed AIN-76A control diet with or without 0.02% sulindac for 6 months. Intestinal regional tumor incidence, multiplicity, volume and degree of inflammation were used as end points. The results showed the following: (i) sulindac inhibited tumor development in the small intestine of Apc(1638N/+) mice; (ii) in contrast, sulindac increased tumors in the small intestine of Mlh1 mutant mice, a neoplastic effect which persisted in heterozygous compound Mlh1(+/-)Apc(1638N/+) mutant mice; (iii) sulindac increased tumors in the cecum of all mice regardless of genetic background; (iv) sulindac decreased inflammation in the small intestine of Apc(1638N/+) mice, but it increased inflammation in the small intestine of Mlh1(+/-) mice and Mlh1(+/-)Apc(1638N/+) mice and (v) sulindac enhanced inflammation in the cecum of all mutant mice. Findings indicate that the effects of sulindac in the intestine of these mutant mouse models are probably related to genetic background and appear to be associated with its inflammatory-inducing response.

[Strategy for patients with GIST after failure of imatinib].

Sunitinib malate(SU11248)is an oral multitargeted receptor tyrosine kinase inhibitor(MTI)that has antitumor activities for patients with gastrointestinal stromal tumor; GIST after failure of Imatinib. Sunitinib has demonstrated significant clinical benefits, including PFS, RR and OS in the USA and Japan. However, cis-mutations in the activation loop of the KIT gene tend to develop Sunitinib-resistant GIST. Two clinical trials revealed that new multitargeted receptor tyrosine kinase inhibitors, Sorafenib and Nilotinib, had antitumor activities for Sunitinib-resistant GIST with longer PFS and a different spectrum. Now, clinical trials of several new MTIs are ongoing in Western countries. Inhibition of the KIT gene cis-mutations and antiangiogenesis activities may be essential for the strategy for Imatinib/Sunitinibresistant GIST.

Chemopreventive effects of orange peel extract (OPE). II: OPE inhibits atypical hyperplastic lesions in rodent mammary gland.

Cancer chemoprevention via the ingestion of natural substances is a current topic of considerable interest. Flavonoids are a family of biologically active phytochemicals having a variety of biological effects. Orange peel extract (OPE) is an abundant source of polymethoxyflavones (PMFs) with potential chemopreventive properties. The OPE used here was a mixture containing tangeretin (19.0%), heptamethoxyflavone (15.24%), tetramethoxyflavone (13.6%), nobiletin (12.49%), hexamethoxyflavone (11.06%), and sinensitin (9.16%). C57Bl/6 mice were fed a new "Western-style" diet (NWD), which had previously induced atypical hyperplasias in mammary gland, and NWD supplemented with a standardized OPE containing 30% PMFs. Mice were fed one of four diets: (1) AIN-76A diet (control); (2) NWD; 0.25% OPE in NWD; or (4) 0.5% OPE in NWD. After 3 months of feeding, atypical hyperplasias developed in mammary glands of mice fed NWD, but not in controls. After feeding OPE in NWD, atypical hyperplasias per mouse decreased in frequency compared to feeding NWD alone (P < .05 in mice fed 0.25% OPE). Apoptosis increased in OPE-treated groups (P < .01) with no inhibition of mitosis. Thus, a standardized preparation of OPE with 30% PMFs decreased development of an atypical hyperplastic lesion and increased apoptosis in ductal epithelial cells of mouse mammary gland.

Chemopreventive effects of orange peel extract (OPE). I: OPE inhibits intestinal tumor growth in ApcMin/+ mice.

Orange peel is a rich source of flavonoids with polymethoxyflavones as major constituents, compounds associated with potential antioxidant, anti-inflammatory, and antitumor activities. We studied the effect of an orange peel extract (OPE) on intestinal tumor growth in Apc(Min/+) mice, a mouse model for human familial adenomatous polyposis (FAP). The OPE contained 30% polymethoxyflavones, a mixture that included tangeretin (19.0%), heptamethoxyflavone (15.24%), tetramethoxyflavone (13.6%), nobiletin (12.49%), hexamethoxyflavone (11.06%), and sinensitin (9.16%). Apc(Min/+) mice were fed one of four diets: (1) AIN-76A control diet; (2) a new Western-style diet (NWD), i.e., AIN-76A diet modified with decreased calcium, vitamin D, and methyl-donor nutrients and increased lipid content); (3) NWD with 0.25% OPE; and (4) NWD with 0.5% OPE, with all additives premixed in the diet. After 9 weeks of feeding NWD to the Apc(Min/+) mice, tumors increased mainly in the colon, with tumor multiplicity increasing 5.3-fold and tumor volume increasing 6.7-fold. After feeding 0.5% OPE in NWD, the development of tumors markedly decreased, with multiplicity decreasing 49% in the small intestine and 38% in the colon. NWD also led to increased apoptosis in intestinal tumors, and 0.5% OPE in NWD further increased apoptosis in tumors of the small and large intestine. Findings indicated that OPE inhibited tumorigenesis in this preclinical mouse model of FAP, and increased apoptosis may have contributed to this effect.

Retroperitoneal perforation arising from duodenal diverticulum treated by endoscopic drainage: a case report.

Retroperitoneal perforation of duodenal diverticula around the papilla of Vater is relatively rare. In this report, we describe retroperitoneal abscess, which was successfully treated by endoscopic drainage. Thus, endoscopic approach for retroperitoneal perforation caused by diverticulum is one of the treatment options in addition to surgery.

Independent antitumor spectrum of UCN-01 (7-hydroxystaurosporine) against gastric and colorectal cancers as detected by MTT assay.

To evaluate the clinical usefulness of 7-hydroxystaurosporine (UCN-01), we compared the antitumor spectrum of UCN-01 with those of conventional antitumor agents against 40 fresh gastric and 40 fresh colorectal cancer specimens using the MTT assay. At a cut-off concentration of 30 micrograms/ml, UCN-01 showed a higher efficacy rate than mitomycin C (MMC), cisplatin, and 5-fluorouracil (5-FU) against both gastric and colorectal cancers. With respect to the gastric cancer specimens, the antitumor spectrum of UCN-01 was independent from those of the other agents, while the patterns of antitumor effects of the conventional agents all correlated significantly with each other. For the colorectal cancer specimens, the pattern of UCN-01-sensitivity did not correlate with the patterns for 5-FU or MMC. In conclusion, UCN-01 may be useful for clinical application against gastric and colorectal cancer due to its different antitumor spectrum from conventionally available agents.

Surgically treated Cronkhite-Canada syndrome associated with gastric cancer.

Cronkhite-Canada syndrome is generally accepted to be a benign disorder, with 374 reported cases to the present. Worldwide, there have been 18 previously reported cases of Cronkhite-Canada syndrome associated with gastric cancer. In this report we describe a case of a 52-year-old man with the clinical features of Cronkhite-Canada syndrome combined with gastric cancer. Although the gastric tumor was located at the antrum of the stomach, we performed a total gastrectomy because of the edematous swelling and high risk of malignancy in the remnant stomach. As Cronkhite-Canada syndrome may be a premalignant condition for gastric cancer, as well as for colorectal cancer, we suggest periodic examination of the stomach, colon, and rectum for patients with Cronkhite-Canada syndrome.

UCN-01 (7-hydroxystaurosporine) inhibits the growth of human breast cancer xenografts through disruption of signal transduction.

BACKGROUND: 7-Hydroxystaurosporine (UCN-01), originally isolated as a phospholipid-dependent protein kinase C inhibitor, has been shown to have antitumor activity against several human cancer cell lines. UCN-01 inhibits cell cycle progression from the G1 to S phase by inhibition of cyclin-dependent kinase (CDK) activity and induction of intrinsic CDK inhibitor protein, leading to dephosphorylation of retinoblastoma (Rb) protein. MATERIALS AND METHODS: The antitumor activity of UCN-01 has been investigated against three human breast carcinoma strains serially transplanted into nude mice, including estrogen-dependent MCF-7, Br-10, and estrogen-independent MX-1. When the inoculated tumors started growing exponentially, UCN-01 (7.5 mg/kg) was administered intraperitoneally on five consecutive days a week for 2 weeks. The antitumor effect was evaluated as the lowest T/C ratio (%) during the experiments, where T was the relative mean tumor weight of the treated group and C was that of the control group. At the end of UCN-01 administration expression of p21, a protein of the CDK inhibitor family, and phosphorylated and dephosphorylated Rb protein was detected by Western blotting using treated and control tumors. RESULTS: UCN-01 had activity against MCF-7 and Br-10, with the lowest T/C ratios of 25.0% and 27.0%, respectively, while MX-1 was resistant to UCN-01 with a T/C ratio of 65.9%. The antitumor spectrum of UCN-01 was different from that of other conventional agents such as doxorubicin and cyclophosphamide which were ineffective against Br-10 but were active against MX-1. Although p21 was induced in three tested strains by UCN-01, little dephosphorylated Rb protein was expressed in MX-1 compared with Br-10 and MCF-7 (in vitro). CONCLUSION: UCN-01 appeared to be a promising agent for the treatment of breast cancer, with a different mode of action and antitumor spectrum from other currently available antitumor drugs.

[A case of residual gastric cancer accompanied by esophageal invasion in which residual lesions were eradicated by half-dose administration of TS-1].

The patient was a 64-year-old male. On November 21, 1991, he underwent gastric resection on the pyloric side for early gastric cancer in the authors' hospital, and did not experience recurrence for many years thereafter. However, endoscopic examination of the upper gastrointestinal tract performed on June 11, 1999 revealed advanced cancer in the posterior wall of the residual stomach which was accompanied by invasion of the esophagus. Thus, the residual stomach was completely removed on July 5, 1999. The histopathological findings were tub1, se, ly3, v2, aw(-), ow(+) and ew(+), and a portion of the esophageal stump and the serosa of the lesser curvature were positive for cancerous tissue. Endoscopic examination was performed one month after the operation, on August 7, 1999. A forceps biopsy taken from an elevated lesion of the esophagus at the posterior wall of the anastomosis revealed adenocarcinoma cells in the lower layer of the squamous epithelium. A residual esophageal lesion was thus diagnosed. Beginning on August 9, 1999, TS-1 was administered in a dosage of 50 mg bid, but it was later learned that the patient had ingested only half of that TS-1 dosage (i.e., 50 mg/day). After completion of one course of this therapy, endoscopy was again performed. It was found that the prominence on the esophageal mucosa at the anastomosis, which had been diagnosed as being cancerous tissue, had shrunk in size, while a forceps biopsy taken from the same site yielded no findings of malignancy. The patient was followed for 18 months thereafter, and endoscopy was performed three times during that interval but continued to yield no evidence of malignancy. As of February 2001, this patient had completed 12 courses of TS-1 at one-half its usual dosage. There have been no findings of recurrence, and the patient's course continues to be good. In summary, this was an interesting case in which residual cancer was detected in the esophageal stump following resection for gastric cancer, and it can be concluded that TS-1 therapy was effective in spite of being incomplete (i.e., half-dose), eradicating the residual cancer tissue.

[A clinical results of TS-1 in advanced and recurrent gastric cancer in our hospital].

A total of 40 patients with advanced and recurrent gastric cancer in our hospital were treated with TS-1 alone, and the efficacy of treatment, survival time, and adverse effects were examined. TS-1 was administered with the usual dosage and dose regimen. Response to treatment included a complete response (CR) in 3 cases, partial response (PR) in 8 cases, no change (NC) in 10 cases, and progressive disease (PD) in 7 cases. The response rate was 39.3%, and among the 28 patients with evaluable lesions TS-1 produced a high response rate of 56.3% in 16 patients who had undergone prior therapy. The median survival time (MST) was 478 days in the 28 patients with evaluable lesions, excluding patients with peritoneal dissemination, and 283 days in the 12 patients with peritoneal dissemination. The outcome was markedly poorer in the patients with peritoneal dissemination than in the patients with evaluable lesions. The incidence of grade 3 or higher adverse effects was 20%, including two cases in which decreased dihydropyrimidine dehydrogenase (DPD) activity was suspected, and one case in which decreased dihydropyrimidinase (DHP) was suspected. Although the effect of TS-1 alone on gastric cancer is significantly superior to that of any conventional cancer drugs, the results of this study suggest that the antitumor effect varies with the site of the target lesions and according to whether the lesion is a remnant or recurrence.

Possible chemoresistance-related genes for gastric cancer detected by cDNA microarray.

To identify chemoresistance-related genes of gastric cancer, we utilized cDNA microarray technology. Thirty-five gastric cancer specimens surgically resected at our institute between 1998 and 1999 were studied for quantification of expression of 6300 genes by means of oligonucleotide microarray methods, and the results were evaluated in comparison with the chemoresistance of the specimens, which was determined by MTT (tetrazolium-based 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Inhibition rates (IR) were determined for cisplatin (DDP), 5-fluorouracil (5-FU), mitomycin C or doxorubicin. IR of 60% or more was regarded as sensitive to each agent, and IR of less than 40% was defined as resistant. Clustering was successfully completed for DDP, resulting in selection of 23 candidates as DDP-resistance-related genes, including vascular permeability factor, 2 membrane transporting subunits, and retinoblastoma-binding protein-1. In addition, further selection of DDP-resistance-related genes was performed according to these criteria: 1) Expression of the gene can be detected in more than 70% of resistant tumors. 2) Expression can be detected in less than 30% of sensitive tumors. 3) Expression in tumors is more than twice that of normal mucosa in more than 50% of specimens. Then, metallothionein-IG and heparin-binding epidermal growth factor-like growth factor (HB-EGF) were identified as candidate DDP-resistance-related genes. When known DDP-resistance-related genes were analyzed according to the MTT assay result, families of glutathione-S-transferase and cyclooxygenase-2 genes were also evaluated as resistance-related genes. For 5-FU resistance, dihydropyrimidine dehydrogenase and HB-EGF-like growth factor genes were also suggested to be resistance-related genes. The present study demonstrated that oligonucleotide microarrays can provide information regarding chemoresistance factors in cancer.