Do stocked hatchery-reared juveniles ecologically suppress wild juveniles in Salvelinus leucomaenis?

The dominancy of semi-wild and hatchery-reared white-spotted charr Salvelinus leucomaenis juveniles was evaluated using pair-wise enclosure tests and field stocking tests. The semi-wild S. leucomaenis originated in a hatchery, being stocked into the test stream as eyed-eggs. In the pair-wise enclosure test, the semi-wild S. leucomaenis dominated the hatchery S. leucomaenis that were of a similar standard length (L(S) ). The semi-wild S. leucomaenis were subordinate to hatchery S. leucomaenis that were > 11% larger in LS . In the field stocking test, the abundance and growth of semi-wild S. leucomaenis was decreased in the presence of larger hatchery S. leucomaenis (14% larger LS ). Taken together, these results suggest that larger hatchery S. leucomaenis ecologically suppress the smaller semi-wild S. leucomaenis. Salvelinus leucomaenis juveniles that are stocked with the intention of supplementing natural populations should be < 10% larger than their wild counterparts at the time of stocking to minimize their competitive advantage. The semi-wild and hatchery S. leucomaenis used in both tests were genetically similar individuals, suggesting that the differences are due to the early rearing environment of either a natural stream or hatchery. The hatchery S. leucomaenis have lower levels of aggression as a result of selection in the hatchery rearing environment. Rearing in a natural stream from the eyed-egg stage is likely to increase their lowered aggression.

Abstract P3-14-08: A randomized phase II trial comparing docetaxel plus cyclophosphamide with epirubicin plus cyclophosphamide followed by docetaxel as neoadjuvant chemotherapy for hormone receptor-negative breast cancer. Kanagawa breast oncology group (KBOG) 1101 study

Background: Taxane-based regimens have been developed and used widely to treat breast cancer. It has therefore become important to identify subgroups of patients in which anthracyclines are indispensable. Pathological response to neoadjuvant chemotherapy (NAC) predicts prognosis in hormone-negative subtypes. We therefore initiated a randomized phase II NAC study to compare a taxane with and without an anthracycline in these breast-cancer subtypes.

Aim: To determine the safety and activity of six cycles of docetaxel and cyclophosphamide (TC6) compared with 5-fluorouracil, epirubicin, and cyclophosphamide followed by docetaxel (FEC-D), and to examine the predictive factors for each regimen.

Methods: Eligibility criteria were operable hormone-receptor-negative breast cancer, age younger than 75 years and ECOG PS0-1. According to HER2 status, patients were randomly assigned to TC (75/600 mg/m2) every 3 weeks X 6 or FEC (500/100/500 mg/m2) every 3 weeks X 3 followed by D (100 mg/m2) every 3 weeks X 3. The primary endpoint was the rate of pathological complete response (pCR; grade 3). Triple-negative (TN) breast cancer was subdivided by cytokeratin 5/6 and epidermal growth factor receptor into basal- and non-basal subtypes. Secondary endpoints were safety, breast-conserving surgery, disease-free survival, overall survival, and predictive factors: Ki-67, p53, aldehyde dehydrogenase (ALDH) 1 and topoisomerase 2A by both immunohistochemistry and fluorescence in situ hybridization for each regimen.

Results: Ninety-seven of 103 patients were analyzed successfully (50 for FEC-D and 47 for TC6). Significantly more severe adverse events (grade 2) were observed in FEC-D-treated patients (poor appetite, nausea and vomiting: p = 0.001; febrile neutropenia: p = 0.016). The pCR rate tended to be higher in FEC-D-treated patients compared with TC6-treated patients (pCR: 36.0 vs. 25.5%, n.s.). FEC-D treatment was significantly more effective than TC6 in basal-type (p = 0.033) but not in non-basal and HER2 subtypes. ALDH1 was associated with resistance to both regimens (FEC-D: p = 0.047, TC6: p = 0.085)

Conclusions: TC6 was safer, but not more effective than FEC-D. TC6 was significantly less active than FEC-D in basal subtype, and equivalent to FEC-D in HER2 and non-basal subtypes. Concurrent use of trastuzumab with TC could thus represent a reasonable option for NAC in HER2-subtype patients. ALDH1 could provide a marker for novel strategies such as stem cell-based therapies for breast cancer. Analyses on pathological factors in surgical specimens after NAC will be presented at the meeting.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-14-08.

Chronic Cadmium Treatment Induces Tubular Nephropathy and Osteomalacic Osteopenia in Ovariectomized Cynomolgus Monkeys

In an attempt to establish a primate model of chronic cadmium toxicosis, we ovariectomized cynomolgus monkeys and treated them with CdCl2 by repeated intravenous injections for 13 to 15 months. The animals showed normocytic-normochromic anemia. The cadmium treatment resulted in increases of urinary enzyme activity indicative of renal tubular degeneration. Histopathology of the kidney revealed renal proximal tubular atrophy accompanied by interstitial fibrosis. Decreased bone mineral density was evident in the trabecular and cortical zones of the lumbar vertebra and femur, with osteoid accumulation around the trabeculae and Haversian canals. Iron deposition at the mineralization front and osteoclasts hyperplasia were indicative of impairment of bone mineralization and an increase of resorption. Blood inorganic phosphorus and 1α,25(OH)2 vitamin D3 levels decreased and urinary deoxypyridinoline level increased in cadmium-treated animals. The renal and bone lesions closely resemble those of itai-itai disease patients, the most severe case of cadmium toxicosis in terms of clinical chemistry and histopathology. Thus, ovariectomized monkeys chronically exposed to cadmium can serve as a primate itai-itai disease model, which is beneficial for developing novel therapeutic methods, investigating the mechanisms of the renal and bone lesions, and establishing more clearly defined criteria for diagnosing the disease.

Thyroid follicular adenoma with accumulation of collagen type IV in a common marmoset (Callithrix jacchus)

A thyroid tumour was identified in a 10-year-old male common marmoset (Callithrix jacchus). The tumour was encapsulated by fibrous connective tissue and compressed the adjacent normal thyroid. The tumour was composed of variably sized and irregularly shaped thyroid follicles lined by a single layer of columnar epithelial cells. Eosinophilic material at the base of the neoplastic cells stained black with periodic acid-methenamine silver and red with periodic acid-Schiff. Immunohistochemistry confirmed that this eosinophilic material was collagen type IV. Ultrastructurally, highly dense and amorphous material was observed at the base of the neoplastic cells. Small vesicles in the basolateral cytoplasm of the neoplastic cells contained similar material to that at the base of the cells. The tumour was diagnosed as a thyroid follicular adenoma with accumulation of collagen type IV. This is the first description of an endocrine tumour with accumulation of collagen type IV in animals.

RUNX1, but not its familial platelet disorder mutants, synergistically activates PF4 gene expression in combination with ETS family proteins

BACKGROUND

Familial platelet disorder (FPD) is a rare autosomal dominant disease characterized by thrombocytopenia and abnormal platelet function. Causal mutations have been identified in the gene encoding runt-related transcription factor 1 (RUNX1) of FPD patients.

OBJECTIVES

To elucidate the role of RUNX1 in the regulation of expression of platelet factor 4 (PF4) and to propose a plausible mechanism underlying RUNX1-mediated induction of the FPD phenotype.

METHODS

We assessed whether RUNX1 and its mutants, in combination with E26 transformation-specific-1 (ETS-1), Core-binding factor subunit beta (CBFβ), and Friend leukemia virus integration 1 (FLI-1), cooperatively regulate PF4 expression during megakaryocytic differentiation. In an embryonic stem cell differentiation system, expression levels of endogenous and exogenous RUNX1 and PF4 were determined by real-time RT-PCR. Promoter activation by the transcription factors were evaluated by reporter gene assays with HepG2 cells. DNA binding activity and protein interaction were analyzed by electrophoretic mobility shift assay and immunoprecipitation assay with Cos-7 cells, respectively. Protein localization was analyzed by immunocytochemistry and Western blotting with Cos-7 cells.

RESULTS

We demonstrated that RUNX1 activates endogenous PF4 expression in megakaryocytic differentiation. RUNX1, but not its mutants, in combination with ETS-1 and CBFβ, or FLI-1, synergistically activated the PF4 promoter. Each RUNX1 mutant harbors various functional abnormalities, including loss of DNA-binding activity, abnormal subcellular localization, and/or alterations of binding affinities for ETS-1, CBFβ, and FLI-1.

CONCLUSIONS

RUNX1, but not its mutants, strongly and synergistically activates PF4 expression along with ETS family proteins. Furthermore, loss of the RUNX1 transcriptional activation function is induced by various functional abnormalities.