Effects of transplantation sites on tumour growth, pulmonary metastasis and ezrin expression of canine osteosarcoma cell lines in nude mice

To determine the influence of the transplantation site of canine osteosarcoma (OS) cell lines on tumour growth and pulmonary metastasis, three OS cell lines were transplanted into nude mice via subcutaneous (SC), intratibial (IT) or intravenous (IV) injection. IT-xenografts exhibited greater potential for developing primary masses and pulmonary metastasis than SC-xenografts. In IT and IV xenografts, lung micrometastases along with phosphorylated ezrin-radixin-moesin (p-ERM) overexpression were found in mice xenografted with HMPOS and OOS cells after 1 week and metastasis was found with decreased p-ERM expression at later time points. The expression of ezrin and p-ERM in the primary tumours of IT-xenografted mice was higher than those in SC-xenografted mice with HMPOS and OOS cells. The results suggest that the orthotopic transplantation site plays an important role in the spontaneous metastasis of canine OS and that ezrin phosphorylation may be involved in the early metastatic mechanism of canine OS cells.

Comparison of actual tidal volume in neonatal lung model volume control ventilation using three ventilators

In neonates, small changes in tidal volumes (V(T)) may lead to complications. Previous studies have shown a significant difference between ventilator-measured tidal volume and tidal volume delivered (actual V(T)). We evaluated the accuracy of three different ventilators to deliver small V(T) during volume-controlled ventilation. We tested Servo 300, 840 ventilator and Evita 4 Neoflow ventilators with lung models simulating normal and injured neonatal lung compliance models. Gas volume delivered from the ventilator into the test circuit (V(TV)) and actual V(T) to the test lung were measured using Ventrak respiration monitors at set V(T) (30 ml). The gas volume increase of the breathing circuit was then calculated. Tidal volumes of the SV300 and PB840 in both lung models were similar to the set V(T) and the actual tidal volumes in the injured model (20.7 ml and 19.8 ml, respectively) were significantly less than that in the normal model (27.4 ml and 23.4 ml). PB840 with circuit compliance compensation could not improve the actual V(T). V(TV) of the EV4N in the normal and the injured models (37.8 ml and 46.6 ml) were markedly increased compared with set V(T), and actual V(T) were similar to set V(T) in the normal and injured model (30.2 ml and 31.9 ml, respectively). EV4N measuring V(T) close to the lung could match actual V(T) to almost the same value as the set V(T) however the gas volume of the breathing circuit was increased. If an accurate value for the patient's actual V(T) is needed, this V(T) must be measured by a sensor located between the Y-piece and the tracheal tube.

[Bronchial injury due to double-lumen endobronchial tube]

A 68-years-old and 148 cm tall female with lung cancer was operated on a left lower lobectomy via posterolateral thoracotomy. A 35 Fr double-lumen endobronchial tube was smoothly inserted and the tip was placed in the left main bronchus whose position was confirmed by fiberoptic bronchoscope. After lobectomy and lymph node dissection were completed, 1-lung ventilation was terminated, the left chest cavity was filled with saline, and an air-leak test was performed. Immediately after the initiation of bilateral lung ventilation, massive air-leak was observed in the left hilar region and the saline in the chest regurgitated into the airway, and she fell into critical ventilatory insufficiency. After sucking the saline in the chest, thorough observation revealed a 3 cm-long rupture of the membranous portion of the left main bronchus. The rupture was manually occluded and ventilatory insufficiency was avoided, then the tip of the endobronchial tube was re-inserted into the right main bronchus and right single lung ventilation was initiated. The rupture was closed by a 4-0 polydioxanone (PDS) running suture with no coverage. The patient was extubated immediately after the operation. Ten days later, she had a tiny bronchial fistula, and it was cured by chest drainage only, and she discharged home on the 48th postoperative day.

Silencing of ferrochelatase enhances 5-aminolevulinic acid-based fluorescence and photodynamic therapy efficacy

Background:

Recurrence of glioma frequently occurs within the marginal area of the surgical cavity due to invading residual cells. 5-Aminolevulinic acid (5-ALA) fluorescence-guided resection has been used as effective therapeutic modalities to improve discrimination of brain tumour margins and patient prognosis. However, the marginal areas of glioma usually show vague fluorescence, which makes tumour identification difficult, and the applicability of 5-ALA-based photodynamic therapy (PDT) is hampered by insufficient therapeutic efficacy in glioma tissues.

Methods:

To overcome these issues, we assessed the expression of ferrochelatase (FECH) gene, which encodes a key enzyme that catalyses the conversion of protoporphyrin IX (PpIX) to heme, in glioma surgical specimens and manipulated FECH in human glioma cell lines.

Results:

Prominent downregulation of FECH mRNA expression was found in glioblastoma tissues compared with normal brain tissues, suggesting that FECH is responsible for PpIX accumulation in glioblastoma cells. Depletion of FECH by small interference RNA enhanced PpIX fluorescence after exposure to 5-ALA concomitant with increased intracellular PpIX accumulation in glioma cells. Silencing of FECH caused marked growth inhibition and apoptosis induction by PDT in glioma cells.

Conclusion:

These results suggest that knockdown of FECH is a potential approach to enhance PpIX fluorescent quality for optimising the subjective discrimination of vague fluorescence and improving the effect of 5-ALA-PDT.

Abstract P3-13-05: Estrogen Receptor-Positive Breast Cancer in Japanese Women: Trends in Incidence, Characteristics and Prognosis

Background: The incidence of breast cancer in Japanese women has doubled in all age groups over the past two decades. Patients and Methods: We examined the characteristics of patients and tumors treated in three time periods between 1982 and 2010. Estrogen receptor (ER), progesterone receptor (PgR), and HER2 status were assessed by immunohistochemistry. Correlation of hormone receptor levels with clinicopathological factors and prognosis was analyzed in ER-positive, HER2-negative breast cancer in two age groups (≥50 years vs. >50 years).

Results: A total of 1903 women with breast cancer, who were treated at Nagoya City University Hospital, were included in this study. The frequency of ER-positive breast cancer in women aged 50 years or younger increased greatly over the interval studied (1982-1991: 52.5%, 1992-2001: 72.6%, 2002-2010: 87.1%, P < 0.0001). The frequency of ER-positive tumors was also significantly increased in women over 50 years of age (1982-1991: 69.4%, 1992-2001: 73.3%, 2002-2010: 78.6%, P = 0.029). In ER-positive, HER2-negative breast cancer, tumor grade was negatively correlated with expression levels of ER (P = 0.0029) and PgR (P < 0.0001). Interestingly, PgR levels were significantly higher in women aged 50 years or younger than in women over 50 years old (P < 0.0001). In both age groups, the prognosis for patients with ER-positive, HER2- negative breast cancer significantly improved over time, due to advances in adjuvant therapies. ER and PgR expression levels were not associated with disease-free survival. Lymph node status and tumor size were strong prognostic factors regardless of the biological characteristics of the tumors in ER-positive, HER2-negative breast cancer in both age groups. Conclusions: It is necessary to establish risk factors, both genetic and environmental, capable of predicting the risk of ER-positive breast cancer and thus enable the efficient selection of candidates for hormone receptor-targeted chemoprevention. Furthermore, new approach should be considered to improve survival for node-positive, ER-positive breast cancer.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-13-05.

Estrogen receptor-positive breast cancer in Japanese women: trends in incidence, characteristics, and prognosis

BACKGROUND

The incidence of breast cancer in Japanese women has doubled in all age groups over the past two decades.

PATIENTS AND METHODS

We examined the characteristics of the tumors treated in three time periods between 1982 and 2010. Estrogen receptor (ER), progesterone receptor (PgR) and HER2 status were assessed by immunohistochemistry. Correlation of hormone receptor levels with clinicopathological factors and prognosis was analyzed in ER-positive, HER2-negative breast cancer in two age groups (≤50 years versus >50 years).

RESULTS

The frequency of ER-positive breast cancer in women aged 50 years or younger increased greatly over the interval studied (1982-1991: 52.5%, 1992-2001: 72.6%, 2002-2010: 87.1%, P < 0.0001). The frequency of ER-positive tumors also significantly increased in women over 50 years of age (1982-1991: 69.4%, 1992-2001: 73.3%, 2002-2010: 78.6%, P = 0.029). In ER-positive, HER2-negative breast cancer, tumor grade was negatively correlated with expression levels of ER and PgR. Prognosis for patients with ER-positive, HER2-negative disease significantly improved over time, due to advances in adjuvant therapies.

CONCLUSION

It is necessary to establish risk factors, both genetic and environmental, capable of predicting the risk of ER-positive breast cancer and thus enable the efficient selection of candidates for hormone receptor-targeted chemoprevention.

Intake of n-3 polyunsaturated fatty acids and non-alcoholic fatty liver disease: a cross-sectional study in Japanese men and women

BACKGROUND/OBJECTIVES

Non-alcoholic fatty liver disease (NAFLD) is a common condition, in which abnormal amounts of triglycerides accumulate in hepatocytes and is closely related to cardiovascular diseases and diabetes. Dietary fats contribute 15% of fat accumulation in the liver and regulate hepatic lipid metabolism. The supplementation of n-3 polyunsaturated fatty acids (n-3 PUFAs) improves NAFLD. The aim of this study is to assess the cross-sectional association between dietary n-3 PUFAs and NAFLD in Japanese men and women.

SUBJECTS/METHODS

Participants were middle-aged, apparently healthy, 296 men and 496 women, who did not drink alcohol and who participated in a general health check-up program. Dietary information from the previous month was obtained by the brief-type self-administered diet history questionnaire. NAFLD was diagnosed if abdominal ultrasonography revealed the presence of fatty liver.

RESULTS

The prevalence of NAFLD was 45.3% in men and 17.5% in women. In comparison with the first tertile, multivariate adjusted odds ratios (95% confidence intervals) for the presence of NAFLD in the second and third tertiles for men taking eicosapentaenoic acid (EPA) were 0.59 (0.31-1.14) and 0.45 (0.23-0.90), respectively, (P for linear trend=0.024), and the multivariate adjusted odds ratios (95% confidence intervals) for the presence of NAFLD in the second and third tertiles for men taking EPA+docosahexaenoic acid (DHA) were 0.44 (0.23-0.86) and 0.48 (0.24-0.95), respectively, (P for linear trend=0.035). However, there was no significant relation between NAFLD and each of these nutrients in women.

CONCLUSIONS

Dietary EPA and EPA+DHA may be independent and preventive nutrients for NAFLD in Japanese men.

Comparison of Actual Tidal Volume in Neonatal Lung Model Volume Control Ventilation using Three Ventilators

In neonates, small changes in tidal volumes (VT) may lead to complications. Previous studies have shown a significant difference between ventilator-measured tidal volume and tidal volume delivered (actual VT). We evaluated the accuracy of three different ventilators to deliver small VT during volume-controlled ventilation.

We tested Servo 300, 840 ventilator and Evita 4 Neoflow ventilators with lung models simulating normal and injured neonatal lung compliance models. Gas volume delivered from the ventilator into the test circuit (VTV) and actual VT to the test lung were measured using Ventrak respiration monitors at set VT (30 ml). The gas volume increase of the breathing circuit was then calculated.

Tidal volumes of the SV300 and PB840 in both lung models were similar to the set VT and the actual tidal volumes in the injured model (20.7 ml and 19.8 ml, respectively) were significantly less than that in the normal model (27.4 ml and 23.4 ml). PB840 with circuit compliance compensation could not improve the actual VT. VTV of the EV4N in the normal and the injured models (37.8 ml and 46.6 ml) were markedly increased compared with set VT, and actual VT were similar to set VT in the normal and injured model (30.2 ml and 31.9 ml, respectively). EV4N measuring VT close to the lung could match actual VT to almost the same value as the set VT, however the gas volume of the breathing circuit was increased.

If an accurate value for the patient's actual VT is needed, this VT must be measured by a sensor located between the Y-piece and the tracheal tube.

304. DECIDUAL HtrA3 NEGATIVELY REGULATES TROPHOBLAST INVASION

Controlled trophoblast invasion cell into the maternal decidua (interstitial invasion) is important for placental development. Abnormalities in the invasion process may lead to pregnancy complications. Decidua secrets many factors to control trophoblast invasion. Serine protease HtrA3 is highly expressed in the decidual cells in the late secretory phase of the menstrual cycle and throughout pregnancy. It is highly expressed in first trimester in most trophoblast cell types, but not in the invading interstitial trophoblast. HtrA3 and its family members are down-regulated in a number of cancers and are proposed as tumor suppressors. We hypothesized that HtrA3 is an inhibitor of trophoblast invasion. The current study aimed to investigate whether HtrA3 secreted by decidual cells regulates trophoblast invasion. Human endometrial stromal cells (HESC) were decidualised with estradial, medroxyprogesterone acetate and cyclic AMP. Real-time RT-PCR, western blotting and immunocytochemistry demonstrated that decidualisation increased HtrA3 mRNA and protein expression. HtrA3 was also detected by western blotting in the conditioned media (CM) of decidualised HESC (96h), confirming its secretory nature. For functional studies, wild type and protease inactive mutant HtrA3 were produced using wheat germ cell-free technology. The mutant has negligible protease activity and significantly inhibited the wild type protease activity, supporting its dominant-negative inhibition and utility as a specific inhibitor of the wild type protein. CM of decidualised HESC suppressed invasion of trophoblast HTR-8 cells, whereas inhibition of HtrA3 in the decidual HESC CM by exogeneous addition of HtrA3 mutant increased trophoblast HTR-8 cell invasion. These results strongly support our hypothesis that decidual HtrA3 negatively regulates trophobalst invasion.

Identification of the novel canine CYP1A2 1117 C>T SNP causing protein deletion

The pharmacokinetics of YM-64227 (4-cyclohexyl-1-ethyl-7-methylpyrido[2,3-d]-pyrimidine-2-(1H)-one), a novel and selective phosphodiesterase type 4 inhibitor, was characterized in beagle dogs. Based on the plasma parent drug to major hydroxylated metabolite ratio, 21 dogs were phenotyped as 16 extensive metabolizers (EM) and five poor metabolizers (PM). Nucleotide sequences of CYPs 1A2, 2B11, 2C21, 2D15, 2E1 and 3A12 were investigated in the EM and PM dogs. A CYP1A2 1117 C>T single nucleotide polymorphism was found, which resulted in an amino acid change from an Arg codon to a stop codon at position 373. All dogs phenotyped as PM were T/T homozygous, whereas EMs were C/C homozygous and C/T heterozygous. In Western blotting of liver microsomes, CYP1A protein expression was detected in the C/C and C/T types, but not in the T/T type. Of 65 dogs genotyped using genome DNA, the frequencies of the C and T alleles were 0.61 and 0.39, respectively, suggesting approximately 15% of the dogs would not express the CYP1A2 protein. The findings provide a coherent explanation for the inter-individual variability in the pharmacokinetics of CYP1A2 substrate drugs in dogs.