Expression of MAGE--A restricted to testis and ovary or to various cancers in dogs.

Expression of MAGE-A protein, a family of cancer/testis antigens, was investigated in normal and neoplastic canine tissues. Immunohistochemical analysis of cross-reactions between a mouse anti-human MAGE-A proteins including MAGE-A1, -A2, -A3, -A4, -A6, -A10, and -A12 monoclonal antibody and canine proteins, showed positive immunoreactivity only in testicular spermatogonia and spermatocytes, and ovary oocytes. The immunoreaction was negative in all other tissues tested, including normal tissues of the skin, gingiva, muscle, adipose, connective, salivary gland, lymph node, intestinal mucosa, mammary gland, liver, cartilage, oviduct, endometrium, cerebrum and cerebellum. Use of a scoring system in the investigated tumors showed positive immunoreactivity in 75% (21/28) of melanomas including oral, cutaneous, eyelid, and interdigital melanomas; in 68.7% (22/32) of oral and nasal tumors; in 52.5% (21/40) discrete round cell tumors; and in 40.5% (15/37) of soft tissue sarcomas. Different tumor types also showed large difference in percentage of MAGE-A expression. Although oral squamous cell carcinomas, multicentric lymphomas and extraosseous osteosarcomas showed no expression, overexpression occurred in oral melanomas (81.82%, 18/21), malignant nasal tumors (100%, 3/3) and in transmissible venereal tumors (100%, 10/10). Based on the characteristic expression of MAGE-A in canine germ cells and in various neoplasms, MAGE-A has potential use as an indicator of malignancy but is probably unsuitable for strictly diagnostic purposes (i.e., diagnosis of tumor type).

Overexpression of P-glycoprotein, STAT3, phospho-STAT3 and KIT in spontaneous canine cutaneous mast cell tumours before and after prednisolone treatment.

Prednisolone is a glucocorticoid (GC) commonly used in the treatment of canine mast cell tumours (MCTs); however, resistance to GCs develops in many MCTs following repeated treatment. P-glycoprotein (P-gp), signal transducer and activator of transcription 3 (STAT3) and KIT (CD117) are involved in GC resistance. The aim of this study was to evaluate the response to prednisolone treatment in canine cutaneous MCTs and to investigate the levels of P-gp, STAT3, phospho-STAT3 (pSTAT3) and KIT proteins in MCTs with or without prednisolone treatment. Immunohistochemistry was performed on tumour samples from 41 dogs with cutaneous MCTs. The overall objective response rate (including complete and partial responses) was 51.8% for dogs treated with prednisolone; poorly differentiated or higher stage MCTs had a lower response rate. The median time-span of tumours to reach maximal tumour regression was 14 d (range 3-77 d); 22 (81.5%) reached maximal regression at 21 d. The majority of MCTs overexpressed both P-gp and STAT3 before and after prednisolone treatment. Reduced expression of pSTAT3 and alterations in the KIT expression pattern were observed in MCTs post-treatment. Prednisolone treatment that caused a marked reduction in tumour volume was correlated with reduced pSTAT3 expression. A cytoplasmic KIT staining pattern was correlated with a lower tumour response rate to prednisolone treatment.

Acute response in vivo of a fiber-optic sensor for continuous glucose monitoring from canine studies on point accuracy.

The objective of this study was to evaluate the acute response of Sencil(™), a fiber-optic sensor, in point accuracy for glucose monitoring in vivo on healthy dogs under anesthesia. A total of four dogs with clinically normal glycemia were implanted with one sensor each in the chest region to measure the interstitial glucose concentration during the ovariohysterectomy procedure. The data was acquired every 10 seconds after initiation, and was compared to the concentration of venous plasma glucose sampled during the surgery procedures for accuracy of agreement analysis. In the four trials with a range of 71-297 mg/dL plasma glucose, the collected 21 pairs of ISF readings from the Sencil™ and the plasma reference showed superior dispersion of residue values than the conventional system, and a linear correlation (the Pearson correlation coefficient is 0.9288 and the y-intercept is 14.22 mg/dL). The MAD (17.6 mg/dL) and RMAD (16.16%) of Sencil™ measurements were in the comparable range of the conventional system. The Clarke error grid analysis indicated that 100% of the paired points were in the clinically acceptable zone A (61.9%) and B (38.1%).