Discovery of Inhibitors of Membrane Traffic from a Panel of Clinically Effective Anticancer Drugs.

In addition to their major targets, clinically effective drugs may have unknown off-targets. By identifying such off-targets it may be possible to repurpose approved drugs for new indications. We are interested in the Golgi apparatus as a novel target for cancer therapy, but there is a paucity of candidate Golgi-disrupting drugs. Here, we aimed to identify Golgi-disrupting compounds from a panel of 34 approved anticancer drugs by using HBC-4 human breast cancer cells and immunofluorescence microscopy to visualize the Golgi apparatus. The screen identified five drugs having Golgi-disrupting activity. Four of them were vinca alkaloids (vinorelbine, vindesine, vincristine and vinblastine), and the fifth drug was eribulin. This is the first study to demonstrate that vinorelbine, vindesine and eribulin possess Golgi-disrupting activity. The 5 drugs are known to inhibit tubulin polymerization and to induce microtubule depolymerization. Interestingly, a microtubule-stabilizer paclitaxel did not induce Golgi-disruption, suggesting that the three-dimensionally preserved microtubules are partly responsible for maintaining the Golgi complex. Concerning eribulin, a noteworthy drug because of its high clinical efficacy against advanced breast cancer, we further confirmed its Golgi-disrupting activity in 3 different human breast cancer cell lines, BSY-1, MDA-MB-231 and MCF-7. Golgi-disruption may contribute to anticancer efficacy of eribulin. In conclusion, the present study revealed that 4 vinca alkaloids and eribulin possessed potential Golgi-disrupting activity among a panel of 34 approved anticancer drugs. Other drugs covering various molecular-targeted drugs and classical DNA-damaging drugs showed no Golgi-disrupting effect. These results suggest that tubulin polymerization-inhibitors might be promising candidate drugs with Golgi-disrupting activity.

Monitoring of Serum Carcinoembryonic Antigen Levels after Curative Resection of Colon Cancer: Cutoff Values Determined according to Preoperative Levels Enhance the Diagnostic Accuracy for Recurrence.

OBJECTIVES: Serum carcinoembryonic antigen (CEA) has been widely used for postoperative surveillance for colorectal cancer. However, serum CEA has a poor diagnostic accuracy for detecting recurrence. We tested the hypothesis that determining cutoff values according to the preoperative serum CEA levels would enhance the diagnostic accuracy. METHODS: Serum CEA was measured before and 1-6 months after surgery in 783 patients with curatively resected colon cancer from 2005 through 2013. The cutoff values during surveillance were determined separately according to preoperative serum CEA levels. RESULTS: In patients with negative preoperative serum CEA, the diagnostic accuracy for recurrence was 89.1% when a postoperative cutoff value was set at 5 ng/mL. However, in patients with positive preoperative serum CEA, the diagnostic accuracy was 58.4% when a postoperative cutoff value was set at 5 ng/mL, and was 75.6% when a cutoff value was set at 8 ng/mL. Among patients with positive preoperative serum CEA, the recurrence-free survival rate was significantly lower in patients with a serum CEA of ≥8 ng/mL than those with a serum CEA of <8 ng/mL (p = 0.0018). CONCLUSIONS: The diagnostic accuracy of serum CEA for recurrence is enhanced by separately setting cutoff values according to preoperative serum CEA.

Comparison between oral antibiotics and probiotics as bowel preparation for elective colon cancer surgery to prevent infection: prospective randomized trial.

BACKGROUND: We have already reported that, for patients undergoing elective colon cancer operations, perioperative infection can be prevented by a single intravenous dose of an antibiotic given immediately beforehand if mechanical bowel preparation and the administration of oral antibiotics are implemented. Synbiotics has been reported to reduce the rate of infection in patients after pancreatic cancer operations. The effectiveness of oral antibiotics and probiotics in preventing postoperative infection in elective colon cancer procedures was examined in a randomized controlled trial. METHODS: Three hundred ten patients with colon cancer randomly were assigned to one of three groups. All patients underwent mechanical bowel preparation and received a single intravenous dose of flomoxef immediately before operation. Probiotics were administered in Group A; oral antibiotics were administered in Group B; and neither probiotics nor oral antibiotics were administered in Group C. Stool samples were collected 9 and 2 days before and 7 and 14 days after the procedure. Clostridium difficile toxin and the number of bacteria in the intestine were determined. RESULTS: The rates of incisional surgical-site infection were 18.0%, 6.1%, and 17.9% in Groups A, B, and C, and the rates of leakage were 12.0%, 1.0%, and 7.4% in Groups A, B, and C, respectively, indicating that both rates were lesser in Group B than in Groups A and C (P = .014 and P = .004, respectively). The detection rates of C. difficile toxin were not changed among the three groups. CONCLUSION: We recommend oral antibiotics, rather than probiotics, as bowel preparation for elective colon cancer procedures to prevent surgical-site infections.

Hematogenous metastatic patterns of curatively resected colon cancer were different from those of stage IV and autopsy cases.

The hematogenous metastases of colon cancer have primarily been explained by the cascade hypothesis based on the cadaveric study. However, we experienced several cases with isolated lung metastasis. The metastatic patterns of a total of 982 patients with colon cancer who underwent surgery were reviewed. The incidence of single-site metastasis in curatively resected cases was significantly higher than in Stage IV cases (P = 0.002). The frequency of liver metastasis was significantly lower in curatively resected cases than in Stage IV cases (P < 0.0001). The frequencies of liver metastasis in Stage IV cases and in autopsy cases reported previously were almost the same (84%, 85%). The frequency of metastasis after curatively resection that did not include the liver was 39%, and cases of isolated lung metastases accounted for 19%. The patterns of hematogenous metastases that are inconsistent with the cascade hypothesis are more common than previously thought in clinical cases, especially in curatively resected cases.

Biopsy specimens obtained 7 days after starting chemoradiotherapy (CRT) provide reliable predictors of response to CRT for rectal cancer.

PURPOSE: Preoperative chemoradiation therapy (CRT) significantly decreases local recurrence in locally advanced rectal cancer. Various biomarkers in biopsy specimens obtained before CRT have been proposed as predictors of response. However, reliable biomarkers remain to be established. METHODS AND MATERIALS: The study group comprised 101 consecutive patients with locally advanced rectal cancer who received preoperative CRT with oral uracil/tegafur (UFT) or S-1. We evaluated histologic findings on hematoxylin and eosin (H&E) staining and immunohistochemical expressions of Ki67, p53, p21, and apoptosis in biopsy specimens obtained before CRT and 7 days after starting CRT. These findings were contrasted with the histologic response and the degree of tumor shrinkage. RESULTS: In biopsy specimens obtained before CRT, histologic marked regression according to the Japanese Classification of Colorectal Carcinoma (JCCC) criteria and the degree of tumor shrinkage on barium enema examination (BE) were significantly greater in patients with p21-positive tumors than in those with p21-negative tumors (P=.04 and P<.01, respectively). In biopsy specimens obtained 7 days after starting CRT, pathologic complete response, histologic marked regression according to both the tumor regression criteria and JCCC criteria, and T downstaging were significantly greater in patients with apoptosis-positive and p21-positive tumors than in those with apoptosis-negative (P<.01, P=.02, P=.01, and P<.01, respectively) or p21-negative tumors (P=.03, P<.01, P<.01, and P=.02, respectively). The degree of tumor shrinkage on both BE as well as MRI was significantly greater in patients with apoptosis-positive and with p21-positive tumors than in those with apoptosis-negative or p21-negative tumors, respectively. Histologic changes in H&E-stained biopsy specimens 7 days after starting CRT significantly correlated with pathologic complete response and marked regression on both JCCC and tumor regression criteria, as well as with tumor shrinkage on BE and MRI (P<.01, P<.01, P<.01, P<.01, and P=.03, respectively). CONCLUSIONS: Immunohistochemical expressions of p21 and apoptosis together with histologic changes on H&E-stained biopsy specimens obtained 7 days after starting CRT are strong predictors of the response to CRT.

Clinical significance of and future perspectives for hepatic arterial infusion chemotherapy in patients with liver metastases from colorectal cancer.

The most common site of metastases in patients with colorectal cancer is the liver. Hepatic resection is considered to be the treatment of choice for liver metastasis from colorectal cancer; however, hepatic resection can be performed in only 20 or 25% of all patients. Recurrence develops in the remnant liver or other organs after hepatic resection in over half of all patients with liver-only metastasis. Hepatic arterial infusion (HAI) chemotherapy can provide relatively high concentrations of drugs to microscopic or macroscopic metastases in the liver, with less toxicity than systemic administration. Meta-analyses have shown HAI chemotherapy to have a significantly higher response rate than systemic chemotherapy and its effect on extrahepatic metastases is negligible. HAI chemotherapy provides much better local control of liver metastases from colorectal cancer than systemic chemotherapy. However, well-controlled studies are needed to elucidate the optimal treatment strategies for neoadjuvant and postoperative adjuvant chemotherapy that optimally combine HAI chemotherapy, molecular targeted agents, and systemic chemotherapy such as FOLFOX or FOLFIRI.

A case of isolated paraaortic lymph node recurrence from colon cancer successfully treated with chemoradiotherapy.

Isolated paraaortic lymph node (PALN) recurrence from colorectal cancer is rare and has no established treatment. A 56-year-old woman was referred to our hospital for the treatment of PALN recurrence in June 2005. She had undergone right hemicolectomy for ascending colon cancer two years earlier. The pathological diagnosis in 2003 was a well-differentiated adenocarcinoma with positive PALN metastasis in 3 of 4 dissected nodes (T3, N1b, M1a, stage IVa). At our hospital, chemoradiotherapy was started, with the radiation field determined from positron emission tomography (PET) images. Oral tegafur/uracil (600 mg/day) plus leucovorin (75 mg/day) therapy was also started. Radiotherapy (1.5 Gy/ fraction, total of 45 Gy) was completed in August 2005, while oral chemotherapy was discontinued 3 weeks after it was started due to diarrhea and epigastric discomfort. The serum carcinoembryonic antigen level was 193 ng/ml (N < 5) before treatment and decreased to within normal limits 3 months after initiation of chemoradiotherapy. Complete remission was confirmed by computed tomography (CT) and PET in December 2005 and has continued for more than 6 years. This case shows that chemoradiotherapy is potentially curative for PALN recurrence from colorectal cancer. To our knowledge, this is the first report of more than 5 years disease-free survival in a patient with PALN recurrence from colon cancer treated with chemoradiotherapy.

Bactericidal effects of acidic electrolyzed water on the dental unit waterline.

Many studies have been conducted in the United States regarding the microbial contamination of dental unit waterline, but not in Japan. Recently, acidic electrolyzed water has been used in the medical and dental fields. In this study, we investigated the bactericidal effects of the temporary inflow of acidic electrolyzed water on microbial contamination of the dental unit waterline. First, in order to observe the daily bacterial contamination of the dental unit waterline, water samples were collected at the end of handpieces and three-way syringes before the inflow of acidic electrolyzed water. They were cultured to detect viable bacteria. Later, the inflow of acidic electrolyzed water was conducted through the piping box of the dental unit. Before starting operation on next day, water samples were collected and cultured, as described above. The mean viable bacteria count was 910 -/+ 190 CFU/ml at the end of handpieces, and 521 -/+ 116 CFU/ml at the end of three-way syringes before the inflow of acidic electrolyzed water. However, bacteria were detected in only small numbers at the end of handpieces and three-way syringes on the next day. These results indicated that acidic electrolyzed water could be applied as an appropriate measure against bacterial contamination of the dental unit waterline.