MicroRNA and Messenger RNA Expression Profiles in Canine Mammary Gland Tumor

Abstract

Canine mammary gland tumor (CMT) is the most frequently diagnosed neoplasm in intact female dogs. As prognosis depends on the malignancy of tumors and metastasis levels, early and accurate diagnosis are crucial for prolongation of life expectancy. The genetic similarity of dogs with humans in addition to environmental and physiological similarities make them ideal models for the study of cancer. In this study, we analyzed differentially expressed microRNAs followed by RNA-Seq to investigate the alterations in mRNA levels based on the malignancy (benign, malignant) and the biopsy locations (tumors, surrounding normal tissues). We identified multiple breast cancer-related genes regardless of malignancy. We found cfa-miR-503 to be the only miRNA that showed altered expression in response to malignancy in CMTs. Although further validation is needed, cfa-miR-503 could be used as a potential diagnostic biomarker as well as a potential RNA-based anti-tumor drug in malignant CMTs.

Molecular Markers in Canine Mammary Tumors

“…In this regard, two lncRNAs (lnc40589 and lncRNA34977) with different behavior have been identifi ed in CMT cells. Specifi cally, lnc40589 inhibited the cells' proliferation, invasion and migration, while the opposite effect was registered for lncRNA34977; furthermor e, lncRNA34977 promoted mammary tumorigenesis in mice [89]. In another study, tamoxifen sensitivity and tumor development were affected by lncRNA-42060 through the regulation of the miR-204-5p/SOX4 axis in CMTs [97]…”

“…Several common microRNAs and lncRNAs were identifi ed in CMTs and human breast cancer [88,89]. miRNA expression patterns in CMT showed essential differences between the tumor and normal tissue and between the metastatic and non-metastatic cases [88].…”

“…Long noncoding RNAs (lncRNAs) are described as RNA transcripts longer than 200 nucleotides unrelated to the protein-coding features [89]. Genome-wide investigation discovered many lncRNAs in different cancers characterized by tumor progression and metastasis.…”

“…Genome-wide investigation discovered many lncRNAs in different cancers characterized by tumor progression and metastasis. Also, lncRNAs, including CMTs, were identifi ed as promising novel biomarkers and therapeutic targets for cancer [89]. The online tool FEELnc, comprising 20 canine RNA-seq samples, expands the canine genome annotation to include 10374 lncRNAs and 58640 mRNA transcripts [95].…”

Domestic Animal Models of Central Nervous System Tumors: Focus on Meningiomas

“…Some of the miRNAs listed in Table 8 play a role in canine and feline neoplasms, also. In particular, the role of miRNAs was highlighted in mammary gland tumors, melanomas, osteosarcomas, urothelial carcinomas, leukemia, hemangiosarcomas [278][279][280][281]. For a detailed review see Varvil and dos Santos (2023) [282].…”