Abstract P1-01-09: Ductal carcinoma in situ: A comparative study between histopathological characteristics and imaging findings

Background: The treatment policy for ductal cancer in situ (DCIS) of the breast greatly depends on the spreading diagnosis. However, a problem is that we cannot compare imaging findings with the histopathology of DCIS. The purpose of this study was to investigate the histopathological characteristics of DCIS and the association with imaging findings.

Methods: Subjects were 128 patients from Tokai University Hospital, diagnosed with DCIS. A positive finding on ultrasonography (USG) was defined as Breast Imaging Reporting and Data System (BI-RADS) of US category 3 or above, in mammography (MMG) it was Japan Breast Cancer Society category 2 or above, and in MRI it was BI-RADS-MRI category 3 or above. Histopathologically, we re-classified DCIS into 3 subtypes.

Table. Histopathological classification of the 3 DCIS subtypesSubtypesArchitectures of DCISType 1Flat and/or micropapillaryType 2Cribriform and/or papillaryType 3Solid and/or comedo, solid or comedo with any other architecture patterns, e.g. solid and cribriform or papillary, etc.

The microscopic examination items included the nuclear grade, necrosis and calcification, stromal reactions surrounding DCIS, distribution of DCIS, and with or without adenosis or other benign changes in the background breast. The automated image analysis using figures captured from virtual system are planned to evaluate concentration of DCIS distribution.

Results: 1) The clinical characteristics and association between imaging findings and histopathological classification of the 3 subtypes of DCIS are summarized as: a) Histopathologically, in type 3, there was a higher frequency of necrosis and calcification in the ducts of DCIS (χ2, p<0.001), the number of dilated peri-ductal capillaries was greater than in type 1 (p=0.023), and the distribution of DCIS was concentrated in type 3 (p=0.020); b) In imaging findings, type 3 was easier to detect than type 1 on USG (p=0.008), but there were no significant differences in MMG and MRI. 2) The 14 DCIS cases that could not be detected by USG, showed slight edematous or myxoid change in the stroma histopathologically (p<0.001), and were less likely to be detected by MRI (p=0.004). 3) The 6 MRI un-detected cases were less likely to be detected by USG (p=0.004), and the occurrence of adenosis or other benign changes in the background breast interfered with MRI (p=0.010). Peri-ductal capillaries seemed to be an important factor for MRI detection (p=0.007). 4) The results of automated image analysis will be presented.

Conclusion: USG imaging reflected the histopathological subtypes of DCIS, myxoid changes of the stroma, and the concentration of DCIS ducts. MRI was correlated with the peri-ductal capillaries of DCIS and the changes in the background breast, while MMG can make up for the shortcomings of USG and MRI. It is important for us to keep the histopathological type in mind and interpret the imaging findings comprehensively, when we do a spreading diagnosis of DCIS.

Citation Format: Tang X, Yamashita T, Kumaki N, Tokuda Y, Masuda S. Ductal carcinoma in situ: A comparative study between histopathological characteristics and imaging findings. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-01-09.

Nonlinear increase of X-ray intensities from thin foils irradiated with a 200 TW femtosecond laser

We report, for the first time, that the energy of femtosecond optical laser pulses, E, with relativistic intensities I > 10(21)  W/cm(2) is efficiently converted to X-ray radiation, which is emitted by "hot" electron component in collision-less processes and heats the solid density plasma periphery. As shown by direct high-resolution spectroscopic measurements X-ray radiation from plasma periphery exhibits unusual non-linear growth ~E(4-5) of its power. The non-linear power growth occurs far earlier than the known regime when the radiation reaction dominates particle motion (RDR). Nevertheless, the radiation is shown to dominate the kinetics of the plasma periphery, changing in this regime (now labeled RDKR) the physical picture of the laser plasma interaction. Although in the experiments reported here we demonstrated by observation of KK hollow ions that X-ray intensities in the keV range exceeds ~10(17)  W/cm(2), there is no theoretical limit of the radiation power. Therefore, such powerful X-ray sources can produce and probe exotic material states with high densities and multiple inner-shell electron excitations even for higher Z elements. Femtosecond laser-produced plasmas may thus provide unique ultra-bright X-ray sources, for future studies of matter in extreme conditions, material science studies, and radiography of biological systems.

A novel synthetic vitamin D3 analogue, 2-beta-(3-hydroxypropoxy)-calcitriol (ED-71): its biological activities and pharmacological effects on calcium metabolism

A novel vitamin D3 analogue, [2 beta-(3-hydroxypropoxy)-calcitriol: ED-71] showed a similar Ca-regulating activity as calcitriol in the in vivo and in vitro Ca mobilization test and ex vivo intestinal Ca absorption assay using vitamin D-deficient rats. The differentiation-inducing activity of ED-71 in mouse myeloid leukemia cell line (WEHI-3 cell) was slightly less than that of calcitriol. ED-71 distributes predominantly in plasma as an intact form and its half-life plasma was twice as long as that of calcitriol. Further study revealed that the higher binding potency of ED-71 to plasma-specific vitamin D-binding protein (DBP) compared with that of calcitriol accounts for its stability in the blood circulation. The pharmacological effect of ED-71 for the animal models with osteoporosis seemed to be better than that calcitriol. These results suggest that ED-71 should become a valuable therapeutic long-acting drug for patients with osteoporosis.

Metabolism and transporting system of 22-oxacalcitriol

The binding potencies of OCT to chick intestinal calcitriol receptor and vitamin DBP were approximately 1/8 and 1/600 of the respective values of calcitriol. OCT is circulating mainly as an intact form bound to chylomicrons and/or lipoproteins. Intravenously injected [3H]-OCT to normal rats was quickly decreased from blood and rapid excretion of OCT as a glucuronate into bile was observed. However, significant amounts of radioactivities were recovered in the intact form in liver and intestine even after 24 h. The separation of calcemic and immune and/or differentiation activities may be derived from the rapid turnover and the nonspecific transporting system.

Assessment of four methodologies (microparticle enzyme immunoassay, chemiluminescent enzyme immunoassay, affinity column-mediated immunoassay, and flow injection assay-tandem mass spectrometry) for measuring tacrolimus blood concentration in Japanese liver transplant recipients

Therapeutic drug monitoring (TDM) and subsequent dosage adjustment for individual patients in the treatment with tacrolimus are required after liver transplantation to prevent rejection and over-immunosuppression, which leads to severe infection and adverse reactions including nephrotoxicity. The purpose of this study was to evaluate the analytical performance among commercially available immunoassay methods, which were microparticle enzyme immunoassay (MEIA), chemiluminescent enzyme immunoassay (CLIA), and affinity column-mediated immunoassay (ACMIA), compared with an assay using liquid chromatography-tandem mass spectrometry (LC-MS/MS). In addition, the flow injection assay (FIA-MS/MS) was also evaluated to determine whether it could be available as a new method of analysis in tacrolimus therapy. The blood tacrolimus concentrations in samples from liver transplant recipients (n = 102) were measured using MEIA, CLIA, ACMIA, and LC-MS/MS. Additional blood samples from liver transplant recipients (n = 54) were analyzed using both FIA-MS/MS and LC-MS/MS. Because the assay performance and characteristics of MEIA, CLIA, ACMIA, and FIA-MS/MS are relatively different, the measured data should be carefully considered depending on the methodology.

Genetic diversity and population structure in native chicken populations from myanmar, Thailand and laos by using 102 indels markers

The genetic diversity of native chicken populations from Myanmar, Thailand, and Laos was examined by using 102 insertion and/or deletion (indels) markers. Most of the indels loci were polymorphic (71% to 96%), and the genetic variability was similar in all populations. The average observed heterozygosities (H_O) and expected heterozygosities (H_E) ranged from 0.205 to 0.263 and 0.239 to 0.381, respectively. The coefficients of genetic differentiation (Gst) for all cumulated populations was 0.125, and the Thai native chickens showed higher Gst (0.088) than Myanmar (0.041) and Laotian (0.024) populations. The pairwise Fst distances ranged from 0.144 to 0.308 among populations. A neighbor-joining (NJ) tree, using Nei’s genetic distance, revealed that Thai and Laotian native chicken populations were genetically close, while Myanmar native chickens were distant from the others. The native chickens from these three countries were thought to be descended from three different origins (K = 3) from STRUCTURE analysis. Genetic admixture was observed in Thai and Laotian native chickens, while admixture was absent in Myanmar native chickens.

Anti-high mobility group box 1 monoclonal antibody ameliorates experimental autoimmune encephalomyelitis

High mobility group box 1 (HMGB1) is an established inflammatory mediator when released from cells. Recent studies have implicated extracellular HMGB1 in the pathogenesis of various autoimmune diseases. The objective of this study was to determine whether HMGB1 could be a therapeutic target for experimental autoimmune encephalomyelitis (EAE). In this study, an anti-HMGB1 monoclonal antibody was injected intraperitoneally into a mouse model of EAE. We also measured serum cytokines levels in EAE and anti-HMGB1 monoclonal antibody-treated EAE. As a result, intraperitoneal injection of an anti-HMGB1 monoclonal antibody ameliorated the clinical and pathological severity of EAE and attenuated interleukin-17 up-regulation in serum. In conclusion, HMGB1 is involved in EAE pathogenesis and could trigger inflammation in the central nervous system. The novel aspect of this study is the demonstration that anti-HMGB1 ameliorates EAE. HMGB1 may be a novel therapeutic strategy for multiple sclerosis.

Evaluation of chlorinated benz[a]anthracene on hepatic toxicity in rats and mutagenic activity in Salmonella typhimurium

Chlorinated benz[a]anthracenes (Cl-BaA) are halogenated aromatic compounds (typified by dioxins) found in the environment at relatively high concentrations. Fischer 344 rats were intragastrically administered 0, 1, or 10 mg of Cl-BaA or its parent compound benz[a]anthracene (BaA) per kg of body weight for 14 consecutive days. Both chemicals at 10 mg/kg/day inhibited the gain in body weight, and consequent increase in relative liver weight. Hepatic gene expression of cytochrome P450 (CYP) 1A1, 1A2, and 1B1 was significantly stimulated by administration of BaA (10 mg/kg/day) compared with the control. After administration of Cl-BaA, only the CYP1A2 gene was significantly induced, even at the lower dosage; CYP1A1 and 1B1 mRNA levels remained unchanged in Cl-BaA-treated rats compared with controls. To elucidate the role of such Cl-BaA exposure and induced CYPs at toxicity onset, we investigated the mutagenicity of BaA and Cl-BaA using Salmonella typhimurium TA98 and TA100. BaA and Cl-BaA at 10 μg/plate produced positive results in both strains in the presence of rat S-9. Incubation of Cl-BaA with recombinant rat CYP1A2 produced a significantly higher number of revertant colonies in TA98 and TA100 than in controls, but no such change was observed for BaA. In conclusion, BaA changes its own physiological and toxicological actions by its chlorination; (1) daily exposure to Cl-BaA selectively induces hepatic CYP1A2 in rats and (2) Cl-BaA induces frameshift mutations in the presence of CYP1A2, although BaA does not exert mutagenicity. This indicates that CYP1A2 may metabolize Cl-BaA to active forms.

Abstract P5-01-02: Inter-observer concordance of Ki-67 labeling index in breast cancer: Japan Breast Cancer Research Group (JBCRG) Ki-67 Ring Study

Background: The standardized assessment of Ki-67 labeling index (LI) plays pivotal roles in identifying the patients (pts) with primary breast cancer who could benefit from systemic chemotherapy, in particular among pts with estrogen receptor(ER)-positive cancers. Therefore, in this study, we evaluated the inter-observer concordance of the assessment of Ki-67 LI in archival materials.

Methods: Six surgical pathologists specializing in breast pathology from different Japanese institutions participated in this study. All slides were prepared from archival tissues of breast cancer fixed in 10% buffered formalin for 24 hours in a single institution (KU). Three independent studies were conducted. Study 1) Six consecutive slides were prepared from 5 cases. A slide from each case was stained with MIB-1 (DAKO, Denmark) in each institution according to their routine methods. Total of 30 stained slides were assessed for Ki-67 LI by each pathologist using two different modes of assessment. One is the scoring system in which the rate of positive cells was scored from 1 (0–9 %) to 10 (90–100%) without counting the cell number. The second one is the counting system in which approximately 1000 cells in total were counted in the hot spots and the positive rate was calculated. Study 2) Twenty tumors with Ki-67 LI ranging from 5 to 25 (15 ± 10) %, stained in a single institution (KU) were assessed by each pathologist by the counting system. Study 3) In order to avoid variations by assessment in varied microscopic fields and to further evaluate the variation of threshold of immunointensity interpreted as positive by different pathologists, fifteen printed photographs of Ki-67-stained slides were sent and assessed for Ki-67 LI by each participating breast pathologist.

Results: Study 1) The counting system demonstrated a better correlation of Ki-67 LI among six pathologists than the scoring system {the intraclass correlation coefficient (ICC), 0.66 (95% confidence interval 0.52–0.78) for the counting system, 0.57 (0.42–0.72) for the scoring system}. The two assessment systems showed a moderate correlation {ICC, 0.68 (0.60–0.75)}. Study 2) The assessment of Ki-67 LI in 20 slides with Ki-67 LI of 5 to 25 % demonstrated a correlation similar to that in the specimens with an unrestricted range of Ki-67 LI in the study 1 {ICC, 0.68 (0.50–0.81) for the study 2, 0.66 (0.52–0.78) for the study 1}. Study 3) The assessment of Ki-67 LI in the same photographs yielded a considerably significant concordance among six pathologists {ICC, 0.94 (0.88–0.97)}.

Conclusion: The counting system turned out better than the scoring system in terms of the inter-observer agreement of the Ki-67 LI assessment. The degree of concordance was by no means influenced by the range of Ki-67 LI. The concordance of the Ki-67 LI assessment among six participating pathologists was significantly high when the assessed field was fixed using the same photographs for evaluation, suggesting that the selection of the fields for evaluation is critical. These results suggest that identification of hot spots for evaluation is pivotal for obtaining the accurate Ki-67 LI of breast cancer and still images of these hot spots could provide reproducible results.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-01-02.

Impact of biomarker usage on oncology drug development

WHAT IS KNOWN AND OBJECTIVE

The increasing cost of drug research and development and the decreasing number of new drugs being launched are serious issues for pharmaceutical companies. Biomarkers for predicting drug effectiveness are regarded as useful tools for combating these trends. However, the extent to which these biomarkers actually help in improving drug development is unclear. Here, we investigated the efficiency of biomarker usage in oncology drug development by focusing on stratification markers.

METHODS

Anti-tumour agents for which clinical studies were initiated between 1998 and 2009 were identified using commercially available data sources, and clinical trials registered in ClinicalTrials.gov were examined to identify the use of stratification marker. Phase transition probability for each clinical phase was calculated and analysed along with various other factors that may affect the efficiency of the development process.

RESULTS AND DISCUSSION

Of 908 anti-tumour agents identified, 121 (13·3%) utilized stratification markers in their clinical studies. Phase I, II and III transition probabilities for all agents were 76·4%, 50·8% and 58·5%, respectively. Corresponding Phase I, II and III transition probabilities of agents developed with stratification markers of 90·4%, 69·0% and 85·0%, respectively, were significantly higher than those for agents without stratification markers. Orphan designation positively affected phase transition probabilities of agents without stratification markers in all phases, while it did not affect transition probabilities of agents with stratification markers, except for Phase II. This shows that stratification markers help improve the probability of success in the development of agents without orphan designation.

WHAT IS NEW AND CONCLUSION

Stratification markers contribute to improving the efficiency of development of anti-cancer drugs. The majority of non-orphan drugs are still being developed without stratification markers. Finding reliable stratification markers for all drugs should improve the success rates in drug development.

Loss of multidrug and toxin extrusion 1 (MATE1) is associated with metformin-induced lactic acidosis

BACKGROUNDS AND PURPOSE

Lactic acidosis is a fatal adverse effect of metformin, but the risk factor remains unclear. Multidrug and toxin extrusion 1 (MATE1) is expressed in the luminal membrane of the kidney and liver. MATE1 was revealed to be responsible for the tubular and biliary secretion of metformin. Therefore, some MATE polymorphisms, that cause it to function abnormally, are hypothesized to induce lactic acidosis. The purpose of this study is to clarify the association between MATE dysfunction and metformin-induced lactic acidosis.

EXPERIMENTAL APPROACH

Blood lactate, pH and bicarbonate ion (HCO(3) (-) ) levels were evaluated during continuous administration of 3 mg·mL(-1) metformin in drinking water using Mate1 knockout (-/-), heterozygous (+/-) and wild-type (+/+) mice. To determine the tissue accumulation of metformin, mice were given 400 mg·kg(-1) metformin orally. Furthermore, blood lactate data were obtained from diabetic patients given metformin.

KEY RESULTS

Seven days after metformin administration in drinking water, significantly higher blood lactate, lower pH and HCO(3) (-) levels were observed in Mate1(-/-) mice, but not in Mate1(+/-) mice. The blood lactate levels were not affected in patients with the heterozygous MATE variant (MATE1-L125F, MATE1-G64D, MATE2-K-G211V). Sixty minutes after metformin administration (400 mg·kg(-1) , p.o.) the hepatic concentration of metformin was markedly higher in Mate1(-/-) mice than in Mate1(+/+) mice.

CONCLUSION AND IMPLICATIONS

MATE1 dysfunction caused a marked elevation in the metformin concentration in the liver and led to lactic acidosis, suggesting that the homozygous MATE1 variant could be one of the risk factors for metformin-induced lactic acidosis.

Effect of hypoxia duration on the oxygen-dependent production of a recombinant protein, β-galactosidase, by an animal cell line, F6D2, with a hypoxia-inducible enhancer

Expression of specific genes is a strategy of animal cells for adaptation to oxygen deficiency and the mechanism underlying the hypoxic activation of gene expression may be useful for efficient production of recombinant proteins by animal cells, because oxygen is a limiting factor in animal cell cultures. We prepared an animal cell line harboring the plasmid in which expression of a reporter gene, β-galactosidase, is controlled by an enhancer responsible for the hypoxic activation of gene transcription. The purpose of this paper is to understand this hypoxic production of recombinant proteins quantitatively by a mathematical model originally developed based on the following hypotheses; 1 lacZ (the reporter gene) is transcribed after HIF-1 protein complex is bound to the hypoxic enhancer, 2. β-galactosidase synthesis rate is limited at the transcription of lacZ, 3. HIF-1 is an inactive form under a normal oxygen concentration, 4. Oxygen works as a repressor in the synthesis of HIF-1 protein, 5. Both β-galactosidase and HIF-1 are decomposed according to the first order reaction. The effects of hypoxic duration as well as oxygen concentration on the β-galactosidase production were successfully predicated by the model.

In vitro neuroprotective action of recombinant rat erythropoietin produced by astrocyte cell lines and comparative studies with erythropoietin produced by Chinese hamster ovary cells

In the central nervous system, astrocytes produce erythropoietin (Epo) and neurons express its receptor. To examine whether or not the brain Epo protects the in vitro cultured neurons from glutamate-induced cell death, we established rat astrocyte cell lines containing the plasmid for production of recombinant rat Epo. Epo partially purified from the culture medium showed a neuroprotective effect similar to that of rat Epo produced by Chinese hamster ovary (CHO) cells. Comparison was made in some other properties between Epo produced by these astrocyte cell lines and that by CHO cells.

Erythropoietin enhancer stimulates production of a recombinant protein by Chinese hamster ovary (CHO) cells under hypoxic condition

Oxygen is a limiting nutrient in animal cell culture and its supply is still worthy of improvement for production of useful proteins with a high efficiency. From a different point of view, development of the system by which a high productivity can be maintained even under hypoxic condition as well as under normoxic condition may be important. A number of hypoxia-inducible genes have been found in eucaryotic cells and the induction in most cases, if not all, is due to hypoxic activation of the gene transcription. Transcription of erythropoietin gene is highly hypoxia-inducible and the induction is achieved by binding of a protein, which is widely distributed in animal cells, to a short DNA stretch (erythropoietin enhancer) in the 3' flanking region of erythropoietin gene. Using a hepatoma cell line (Hep3B) that produces the endogenous erythropoietin in an oxygen-dependent manner and Chinese hamster ovary cells that have been widely used for production of recombinant proteins, we show that, under hypoxic condition, the erythropoietin enhancer can activate not only the promoter of erythropoietin gene but also promoters of cytomegalovirus early genes and eucaryotic polypeptide chain elongation factor gene, both of which are very active in animal cells under normoxic condition.

The challenge of acute rejection in intestinal transplantation

Early diagnosis and treatment of acute cellular rejection (ACR) after intestinal transplantation (ITx) is challenging. We report the outcome of three patients: two presented mild ACR improved with steroids. One presented steroid-resistant severe rejection, improved after rabbit anti-thymocyte globulin (r-ATG), but unfortunately died for encephalitis caused by opportunistic infections.

Microfocus x-ray imaging of traceable pointlike (22)Na sources for quality control

PURPOSE

The purpose of this study is to propose a microfocus x-ray imaging technique for observing the internal structure of small radioactive sources and evaluating geometrical errors quantitatively, and to apply this technique to traceable pointlike (22)Na sources, which were designed for positron emission tomography calibration, for the purpose of quality control of the pointlike sources.

METHODS

A microfocus x-ray imaging system with a focus size of 0.001 mm was used to obtain projection x-ray images and x-ray CT images of five pointlike source samples, which were manufactured during 2009-2012. The obtained projection and tomographic images were used to observe the internal structure and evaluate geometrical errors quantitatively. Monte Carlo simulation was used to evaluate the effect of possible geometrical errors on the intensity and uniformity of 0.511 MeV annihilation photon pairs emitted from the sources.

RESULTS

Geometrical errors were evaluated with sufficient precision using projection x-ray images. CT images were used for observing the internal structure intuitively. As a result, four of the five examined samples were within the tolerance to maintain the total uncertainty below ±0.5%, given the source radioactivity; however, one sample was found to be defective.

CONCLUSIONS

This quality control procedure is crucial and offers an important basis for using the pointlike (22)Na source as a basic calibration tool. The microfocus x-ray imaging approach is a promising technique for visual and quantitative evaluation of the internal geometry of small radioactive sources.