8개월령의 단모종 집고양이가 감소된 식욕과 활력 저하로 내원하였다. 진단을 위한 영상 검사에서 종격동의 종괴와 종격동 림프절의 비대 소견을 확인할 수 있었다. 이어서 진행한 세침흡인술 검사로, 악성 림프구를 다수 확인할 수 있었으며, 이 고양이는 다발성 림프종 (병기 V-b)로 진단되었다. 치료는 COP 프로토콜을 사용하였으며, 완전 완화를 확인할 수 있었지만, 항암 치료를 시작한 후 314일 째 재발과 함께 중추신경계로 전이된 소견을 확인할 수 있었다. 구조화학 요법을 실시하여, 단기적으로는 임상증상의 큰 개선을 확인할 수 있었지만, 부분완화만이 관찰되었으며, 처음 내원 부터 약 383일 정도 생존하였다. 부검과 조직병리학적 검사를 통해, 다발성의 T 세포 림프종으로 확인하였으며, 뇌에서도 병변을 확인할 수 있었다.
The presence of the tick-borne pathogens Ehrlichia and Borrelia in German Shepherd dogs in Korea was determined by enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). A total of 291 dogs were randomly selected from five Korean provinces from October 2005 through September 2006. The seroprevalence of antibodies to canine Ehrlichia and Borrelia agents detected by ELISA (Snap ® 3Dx ® Test, IDEXX Laboratories) was 7.56% (22 dogs) and 1.72% (5 dogs) respectively, throughout the country. Positive antibodies against both pathogens were detected in two dogs (0.69%). The provincial distribution of seroprevalence against Ehrlichia was1.28% (1 of 78) in Gyeonggi-do, 12.64% (11 of 87) in Gangwon-do, 9.76% (4 of 41) in Chungcheong-do, 8.93% (5 of 56) in Gyeongsang-do, and 3.45% (1 of 29) in Jeolla-do. According to PCR analysis, Ehrlichia chaffeensis target DNA was amplified in 3.09% (9 of 291 dogs) of blood samples, 2.41% (7 of 291) from Gangwon-do and 0.69% (2 of 291) from Chungcheong-do. The oligonucleotide sequences (SNU-EC3 and SNU-EC5) from the PCR fragment examined in Korea were closely related to E. chaffeensis isolated from the tick Haemaphysalis longicornis, in China and the state of Arkansas in the US. Based on these results, the presence of E. chaffeensis infection was identified in German Shepherds being bred in Korea. These results bring to light the importance of paying close attention to tick-borne infections such as Lyme disease during clinical diagnosis. This infectious disease should be included as a differential diagnosis for patients who participate in outdoor activity from spring to fall or who have thrombocytopenia or leucopenia.
Rivoceranib, a novel tyrosine kinase inhibitor, exhibits anti-tumour effects by selectively blocking vascular endothelial growth factor receptor-2 (VEGFR2) in cancer cells. Recently, the therapeutic effects of rivoceranib on solid tumours have been elucidated in human patients. However, the anti-tumour effects of rivoceranib against canine cancer remain unclear. Here, we investigated the anti-tumour effects of rivoceranib using in vitro and in vivo mouse xenograft models.We performed cell proliferation, cell cycle, and migration assays to determine the effects of rivoceranib on canine solid tumour cell lines in vitro. Furthermore, apoptosis and angiogenesis in tumour tissues were examined using a TUNEL assay and immunohistochemistry methods with an anti-cluster of differentiation-31 antibody, respectively. Additionally, the expression levels of cyclin-D1 and VEGFR2 activity were determined using western blot analysis.Rivoceranib treatment showed anti-proliferative effects and mediated cell cycle arrest in the canine melanoma cell line (LMeC) and the mammary gland tumour (MGT) cell line (CHMp). In animal experiments, rivoceranib decreased the average volume of LMeC cells compared to that following control treatment, and similar results were observed in CHMp cells. Histologically, rivoceranib induced apoptosis and exerted an anti-angiogenic effect in tumour tissues. It also downregulated the expression of cyclin-D1 and inhibited VEGFR2 activity.Our results show that rivoceranib inhibits proliferation and migration of tumour cells. These findings support the potential application of rivoceranib as a novel chemotherapeutic strategy for canine melanoma and MGTs.