Efficacy of Oral Recombinant Methioninase and Eribulin on a PDOX Model of Triple-negative Breast Cancer (TNBC) Liver Metastasis.

BACKGROUND/AIM: The aim of the present study was to identify effective drugs for a highly-aggressive liver-metastasis of triple-negative breast cancer (TNBC) in a patient-derived orthotopic xenograft (PDOX) mouse model. Drugs tested were oral recombinant methioninase (o-rMETase), low-dose eribulin and their combination. MATERIALS AND METHODS: Patient-derived TNBC was implanted in the liver of nude mice by surgical hepatic implantation. Two weeks after transplantation, 32 mice were randomized (n=8 per group) into a phosphate-buffered saline vehicle-control group; o-rMETase-treatment group (100 units, o-rMETase, oral, daily for 2 weeks); eribulin-treatment group (0.05 mg/kg intraperitoneally once per week for 2 weeks); or combination-treatment group (100 units r-METase, oral, daily for 2 weeks + 0.05 mg/kg eribulin intraperitoneally once per week for 2 weeks). RESULTS: After 2 weeks, the three treatment groups exhibited significantly-inhibited TNBC growth in the liver compared to the vehicle-control group (p≤0.05). CONCLUSION: o-rMETase and low-dose eribulin monotherapy and their combination were efficacious against the highly-aggressive TNBC PDOX growing in the liver. The TNBC PDOX model can be used to identify highly-effective drugs for therapy of TNBC with liver metastasis.

Response of Triple-negative Breast Cancer Liver Metastasis to Oral Recombinant Methioninase in a Patient-derived Orthotopic Xenograft (PDOX) Model.

BACKGROUND/AIM: The aim of this study was to establish a patient-derived orthotopic xenograft (PDOX) mouse model of liver metastasis of triple-negative breast cancer (TNBC) and examine the efficacy of oral recombinant methioninase (o-rMETase) on the liver metastasis. MATERIALS AND METHODS: TNBC from a patient was implanted in the left hepatic lobe of nude mice to simulate liver metastasis in a PDOX model. Ten days later, all mice underwent laparotomy to measure tumor size and were randomized to three groups: control; o-rMETase 100 U once daily (qd); and o-rMETase 200 U qd. After 9 days of treatment, all mice were sacrificed. RESULTS: At the end of the treatment period for the liver metastasis, the size of liver metastases was 372.6 mm3 in the control group; 160.0 mm3 in the o-rMETase 100 U group; and 245.3 mm3 in the o-rMETase 200 U group. All mice had ascites and 12 out of 14 mice in all groups had mesenteric lymph-node metastasis, as re-metastasis. The mean body-condition score was 1.5 in the control group; 2.4 in the o-rMETase 100 U group; and 2.6 in the o-rMETase 200 U group (control group vs. o-rMETase 200 U group, p<0.05). CONCLUSION: The TNBC liver metastasis was highly aggressive resulting in re-metastasis and ascites. o-rMETase tended to inhibit the liver metastasis and significantly improved the mouse body-condition score. This new PDOX model of TNBC liver metastasis will be useful for identifying effective agents for this recalcitrant disease.

Oral Recombinant Methioninase Sensitizes a Bladder Cancer Orthotopic Xenograft Mouse Model to Low-dose Cisplatinum and Prevents Metastasis.

BACKGROUND/AIM: The aim of the study was to determine if oral recombinant methioninase (o-rMETase) can sensitize an orthotopic bladder tumor in nude mice to low-dose cisplatinum (CDDP). MATERIALS AND METHODS: The green fluorescent protein (GFP)-expressing UM-UC-3-GFP bladder cancer was surgically orthotopically implanted (SOI) to the bladder in nude mice. The treatment was initiated when the primary tumor volume reached 100 mm3 Mice were assigned to 3 groups: G1: Saline vehicle (0.1 ml per mouse, oral, twice per day); G2: low-dose CDDP (0.5 mg/kg, intraperitoneal twice per week); G3: o-rMETase + low-dose CDDP (100 units per mouse, oral, twice per day + 0.5 mg/kg, intraperitoneal twice per week, respectively). Tumor volume and body weight were measured twice per week. The expression of Ki-67 was detected by immunohistochemistry to evaluate cell proliferation. RESULTS: The combination of o-rMETase and low-dose CDDP increased inhibition efficacy compared to low-dose CDDP monotherapy, on primary-tumor growth (p=0.032) and metastasis (p=0.002). CONCLUSION: The combination of o-rMETase with low-dose CDDP has future clinical potential for bladder cancer.

Oral Methioninase Inhibits Recurrence in a PDOX Mouse Model of Aggressive Triple-negative Breast Cancer.

BACKGROUND/AIM: The aim of the study was to use a triple-negative breast cancer (TNBC) patient-derived orthotopic xenograft (PDOX) model to examine the efficacy of oral recombinant methioninase (o-rMETase) against this recalcitrant disease. MATERIALS AND METHODS: The TNBC tumor from a patient was implanted in the right 4th inguinal mammary fat pad of nude mice. Two weeks later, the mice underwent tumorectomy with grossly-negative surgical margins. Two days after tumorectomy the mice were divided in two groups: one control and one treated with o-rMETase. RESULTS: Tumors recurred in all mice. On day 11, the mean recurrent tumor volumes were 936.7 mm3 in the control group and 450.9 mm3 in the o-rMETase group (p<0.05). On day 15, the mean recurrent tumor volumes were 3392.5 mm3 in the control group and 1603.5 mm3 in the o-rMETase group. The mean recurrent tumor weights were 2.1 g in the control group and 1.1 g in the o-rMETase group on day 15. CONCLUSION: o-rMETase is an effective adjuvant treatment for aggressive TNBC.

A Single Low Dose of Eribulin Regressed a Highly Aggressive Triple-negative Breast Cancer in a Patient-derived Orthotopic Xenograft Model.

BACKGROUND/AIM: In the present study, the breast cancer patient-derived orthotopic xenograft (PDOX) model was used to identify an effective drug for a highly aggressive triple negative breast cancer (TNBC). MATERIALS AND METHODS: The TNBC tumor from a patient was implanted in the right 4th inguinal mammary fat pad of nude mice to establish a PDOX model. Three weeks later, 19 mice were randomized into the untreated-control group (n=10) and the eribulin treatment group (n=9, eribulin, 0.3 mg/kg, i.p., day 1). RESULTS: On day 8, eribulin significantly inhibited tumor volume compared to the control group (p<0.01). Eribulin regressed tumors in 3 mice (33.3%) and apparently eradicated them in 6 mice (66.7%). At day 14, tumor regrowth was observed in 2 mice of the eribulin group, which was undetectable on day 8. However, 44.4% (4 out of 9) of the mice in the eribulin group were tumor-free on day 14. CONCLUSION: A single low-dose eribulin was efficacious on a highly aggressive TNBC. The breast cancer PDOX model can be used to identify highly effective drugs for TNBC.

Appendectomy: Should it Be Performed So Quickly?

Controversy surrounds appendectomy timings and their effects on postoperative outcomes. This study evaluated the influence of hospital delays on perforation rates and complications in patients with acute appendicitis. From January 2008 to December 2013, the cases of 4148 consecutive patients who had undergone appendectomies for suspected appendicitis were reviewed. The patients' demographic data, times from symptom onset to hospital arrival (prehospital delay), times from hospital arrival to surgery (hospital delay), histological findings, and postoperative outcomes were documented. Perforation rates and complications were assessed at each time interval between symptom onset and surgery. Perforation rates and complications increased with longer prehospital delays, but no correlations were evident between hospital delays and perforation rates or between hospital delays and complications. Although delaying appendectomies for >18 hours had no statistically significant impact on perforation rates (25.3 vs 19.4%, P = 0.133), it caused more complications (8.7 vs 3.8%, P = 0.023) compared with cases delayed for 12 to 18 hours. Multivariate analyses determined that hospital delays were not associated with increased risks of perforation, complications, wound infections, or intra-abdominal abscesses. However, a >18-hour hospital delay was associated with a significantly increased risk of postoperative ileus (odds ratio = 2.94, 95% confidence interval = 1.17-7.41, P = 0.022). Hospital delays were not associated with significantly increased risks of perforation and complications. However, patients with perforated appendicitis had higher risks of developing postoperative ileus if hospital delays were >18 hours. Therefore, hospital delays of ≤18 hours are safe, but caution is required if delays are >18 hours.

[The variation of hepatic duct confluence and asymptomatic common bile duct stone with routine intraoperative cholangiogram during laparoscopic cholecystectomy].

BACKGROUND/AIMS: Intraoperative cholangiogram (IOC) during laparoscopic cholecystectomy (LC) has been used to evaluate bile duct stone. But, the routine use of IOC remains controversial. With routine IOC during LC, we reviewed the variation of hepatic duct confluence and try to suggest the diagnostic criteria of asymptomatic common bile duct (CBD) stone. METHODS: We reviewed the medical record of 970 consecutive patients who underwent LC with IOC from January 1999 to December 2009, retrospectively. RESULTS: Nine hundered seventy patients were enrolled. IOC were successful in 957 (98.7%) and unsuccessful in 13 (1.3%). Eighty two of 957 patients (8.2%) were excluded because of no or poor radiologic image. According to Couinaud's classification, 492 patients (56.2%) had type A hepatic duct confluence, 227 patients (26.1%) type B, 15 patients (17%) type C1, 43 patients (4.9%) type C2, 72 patients (8.2%) type D1, 21 patients (2.4%) type D2, 1 patient (0.1%) type E1, 1 patient (0.1%) type E2, 2 patients (0.2%) type F, and 1 patient (0.1%) no classified type. The CBD stone was found in 116 of 970 (12.2%) patients. In 281 patients, preoperative serologic and radiologic tests did not show abnormality. When preoperative findings were not remarkable, there was no difference of clinical features between patients with or without CBD stones. CONCLUSIONS: Although IOC during LC has some demerits, it is a safe and accurate method for the detection of CBD stone and the anatomic variation of intrahepatic duct.

Comparison of calcitriol versus cholecalciferol therapy in addition to oral calcium after total thyroidectomy with central neck lymph node dissection: a prospective randomized study.

BACKGROUND: The purpose of this study was to determine the effectiveness of oral calcium plus vitamin D supplementation and to compare the effects of cholecalciferol versus calcitriol treatments on postoperative hypocalcemia. METHODS: After total thyroidectomy with central neck dissection, 306 patients were divided into 4 groups according to "routine use versus on-demand use" and "cholecalciferol versus calcitriol." RESULTS: Hypocalcemic symptoms developed in 101 patients (33.0%). Hypocalcemia developed less frequently in patients receiving routine supplementation regardless of vitamin D type. However, routine supplementation did not prevent severe hypocalcemia. In patients receiving on-demand supplements, calcitriol was more effective and faster acting than was cholecalciferol. CONCLUSION: Routine oral calcium and vitamin D supplements are beneficial after total thyroidectomy with central neck lymph node dissection with no difference between cholecalciferol and calcitriol. If taken after the onset of hypocalcemia, however, calcitriol along with calcium carbonate seems to be more effective than is cholecalciferol with calcium carbonate.

Does pre-operative breast magnetic resonance imaging in addition to mammography and breast ultrasonography change the operative management of breast carcinoma?

Magnetic resonance imaging (MRI) has been used for the local staging of breast cancer, especially to determine the extent of multiple lesions and to identify occult malignancies. The aim of this study was to evaluate the effect of pre-operative MRI on the surgical treatment of breast cancer. Between January 2006 and May 2007, 535 newly diagnosed breast cancer patients who planned to undergo breast conserving surgery had clinical examinations, bilateral mammography, breast ultrasonography, and breast MRI. The radiologic findings and clinicopathologic data were reviewed retrospectively. Ninety-eight (18.3%) patients had additional lesions, shown as suspicious lesions on breast MRI, but not detected with conventional methods. Eighty-four (15.7%) of these patients had a change in surgical treatment plans based on the MRI results. Forty-seven (8.8%) of the 84 patients had additional malignancies;the other 37 patients (6.9%) had benign lesions. The positive predictive value for MRI-based surgery was 56.0% (47 of 84 patients). During the period of study, the use of pre-operative MRI was increased with time (OR 1.20; 95% CI 1.16-1.23; P < 0.001), but the mastectomy rate did not change significantly (OR 0.98; 95% CI 0.95-1.00; P = 0.059). Multiple factors were analyzed to identify the patients more likely to undergo appropriate and complete surgery based on the additional findings of the pre-operative MRI, but the results were not statistically significant. This research suggests that a pre-operative MRI can potentially lower the rate of incompletely excised malignancies by identifying additional occult cancer prior to surgery and does not lead to an increase in the mastectomy rate; however, because some benign lesions are indistinguishable from suspicious or malignant lesions, excessive surgical procedures are unnecessarily performed in a significant portion of patients. In the future, the criteria for the use of MRI in local staging of breast cancer should be established.

The role of PET CT to evaluate the response to neoadjuvant chemotherapy in advanced breast cancer: comparison with ultrasonography and magnetic resonance imaging.

BACKGROUND: Recently PET is emerged as a method to estimate the response of neoadjuvant chemotherapy (NAC) in advanced breast cancer. This study is aimed to estimate the predictive role of PET CT and other imaging modalities (ultrasound, MRI) through NAC. METHODS: PET CT was acquired before and after NAC from 41 patients. Pathologic results were classified as pathological complete response (pCR) and non-pCR. The results of clinical responses were assessed with imaging indexes (postTx, postchemotherapy size or peak standardized uptake values (pSUV); delta, the size difference between treatment; RR, reduction rate of tumor size or pSUV), and they were compared with pathologic results. RESULTS: Seven patients (17.1%) showed pCR. As a result of comparison of the image index, all image indexes of MRI were predictive for pCR (P < 0.05). In contrast, only delta and RR of US, RR of PET CT were significant. The area under curve of delta and RR in MRI were higher (0.91, 0.90) than US (0.83, 0.80) and PET CT (0.62, 0.72). The MRI is superior to the US or PET CT. CONCLUSIONS: We have concluded that the MRI is better than PET CT for monitoring the effect of NAC in advanced breast cancer.

EGF-induced MMP-9 expression is mediated by the JAK3/ERK pathway, but not by the JAK3/STAT-3 pathway in a SKBR3 breast cancer cell line.

The number of epidermal growth factor receptors (EGFRs) and their ligands are highly expressed in malignant tumor cells. The EGF signaling pathway is also activated in up to one-third of patients with breast cancer. In this study, we investigated the novel function of the JAK3 inhibitor, WHI-P131, on EGF-induced MMP-9 expression and the regulatory mechanism of EGF-induced MMP-9 expression in SKBR3 cells. We observed that EGF increased MMP-9 mRNA and protein expression in a dose-dependent manner. EGF also induced the phosphorylation of EGFR, ERK, and STAT-3, and these effects were inhibited by the EGFR inhibitor, AG1478.To investigate the involvement of the STAT-3 pathway on EGF-induced MMP-9 expression, we pretreatedSKBR3 cells with JAK1, JAK2, and JAK3 inhibitors prior to EGF treatment. The results showed that the JAK3 inhibitor, WHI-P131, as well as JAK3 siRNA transfection, but not the JAK1 and JAK2 inhibitors, significantly decreased EGF-induced MMP-9 expression. In addition, EGF-induced STAT-3 phosphorylation was only inhibited by WHI-P131. We then transfected cells with adenoviral STAT-3 (Ad-STAT-3), followed by treatment with EGF. Interestingly, EGF-induced MMP-9 expression was decreased by Ad-STAT-3 overexpression in a dose-dependent manner, while it was significantly increased by STAT-3 siRNA transfection. Our results also showed that basal levels of MMP-9 expression were significantly increased by constitutive active-MEK (CAMEK)overexpression. EGF-induced ERK phosphorylation was prevented by WHI-P131, but not by JAK1 andJAK2 inhibitors. On the other hand, EGF-induced MMP-9 expression was decreased by the MEK1/2 inhibitor,UO126. Therefore, for the first time, we suggest that the JAK3 inhibitor, WHI-P131, inhibits EGF-induced STAT-3 phosphorylation as well as ERK phosphorylation. The JAK3/ERK pathway may play an important role in EGFinduced MMP-9 expression in SKBR3 cells.

Silibinin prevents TPA-induced MMP-9 expression and VEGF secretion by inactivation of the Raf/MEK/ERK pathway in MCF-7 human breast cancer cells.

Matrix metalloproteinase-9 (MMP-9) and vascular endothelial growth factor (VEGF) expression are pivotal steps in cancer metastasis. Herein, we investigated the effect of silibinin, a major constituent (flavanolignan) of the fruits of Silybum marianum, on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 and VEGF expression in MCF-7 human breast cancer cells. The expression of MMP-9 and VEGF in response to TPA was increased, whereas TPA-induced MMP-9 and VEGF expression was decreased by silibinin. To investigate the regulatory mechanism of silibinin on TPA-induced MMP-9 and VEGF expression, we pretreated cells with various inhibitors, such as UO126 (MEK1/2 inhibitor), SP600125 (JNK inhibitor), and SB203580 (p38 inhibitor). Interestingly, TPA-induced MMP-9 expression was significantly inhibited by UO126, but not by SP600125 and SB203580. In addition, we pretreated cells with 100 microM silibinin prior to TPA treatment. TPA-induced MEK and ERK phosphorylation was significantly decreased by silibinin in MCF7 cells. TPA-induced VEGF expression was also suppressed by UO126. On the other hand, we found that adenoviral constitutive active-MEK (Ad-CA-MEK) significantly increased MMP-9 and VEGF expression. Taken together, we suggest that the inhibition of TPA-induced MMP-9 and VEGF expression by silibinin is mediated by the suppression of the Raf/MEK/ERK pathway in MCF-7 breast cancer cells.

Successful surgical treatment of aortoenteric fistula.

In order to establish optimal management for aortoenteric fistula (AEF) the records of five patients treated for AEF (four aortoduodenal and one aortogastric fistula) were retrospectively reviewed. The arterial reconstruction procedures were selected according to the surgical findings, underlying cause, and patient status. In situ aortic reconstructions with prosthetic grafts were performed on three patients who had no gross findings of periaortic infection, whereas axillo-bifemoral bypass was carried out in the other two patients with periaortic purulence. In all patients, after retroperitoneal irrigation a pedicled omentum was used to cover the aortic graft or aortic stump. In the preoperative abdominal computed tomography (CT) scan there was a periaortic air shadow in four out of five patients. There was no surgical mortality or graft infection observed during a mean follow-up period of 40 months (range, 24-68 months). Therefore, the treatment results of an AEF can be improved using intravenous contrast-enhanced abdominal CT for rapid diagnosis and selection of an appropriate surgical procedure based on the surgical findings and underlying cause.