Venereal Tumors, Veterinary
Dog Diseases
Dogs
Veterinary Medicine
Veterinary Drugs
Sequence analysis of canine LINE-1 elements and p53 gene in canine transmissible venereal tumor. (1/28)
LINEs (long interspersed nuclear elements or long interspersed repeated DNA elements) contains two open reading frames (ORFs), ORF1 and ORF2. We analysed the ORF2 located in the 5' region to the first exon of oncogene c-myc in canine transmissible venereal tumor (TVT) cell. We also showed the transcription activation was induced by this TVT-LINE sequence using CAT assay. To identify the mutation of tumor suppressor gene, sequence analysis of p53 from TVT cell was performed. We identified the point mutation of 964 nucleotide (T-C) resulting in the change of amino acid (Phe-Ser) of p53 tumor suppressor protein. (+info)Tumor-infiltrating lymphocyte secretion of IL-6 antagonizes tumor-derived TGF-beta 1 and restores the lymphokine-activated killing activity. (2/28)
IL-6 is a multifunctional cytokine that regulates cell growth, differentiation, and cell survival. Many tumor cells produce TGF-beta1, which allows them to evade CTL-mediated immune responses. IL-6 antagonizes TGF-beta1 inhibition of CD3 cell activation. However, whether IL-6 restores NK activity, which also is suppressed by TGF-beta1, is not known. We used canine transmissible venereal tumor (CTVT), which produces TGF-beta1, as a model to determine whether IL-6 restores lymphokine-activated killer (LAK) activity. During the progression phase, CTVT cells stop expressing MHC molecules. During the regression phase, the number of surface MHC molecules increases dramatically on about one-third of tumor cells. Tumor cells that stop expressing MHC should be targeted by NK cells. In this study, we found that TGF-beta1 secreted by CTVT cells suppressed LAK cytotoxicity. Interestingly, tumor-infiltrating lymphocytes (TIL) isolated from regressing CTVT secrete high concentrations of IL-6 and antagonize the anti-LAK activity of tumor cell TGF-beta1. TIL also produce IL-6 during progression phase, but the concentration is too low to block the anti-LAK activity of TGF-beta1. There is probably a threshold concentration of IL-6 needed to reverse TGF-beta1-inhibited LAK activity. In addition, in the absence of TGF-beta1, IL-6 derived from TIL does not promote the activity of LAK. This new mechanism, in which TIL manufacture high concentrations of IL-6 to block tumor TGF-beta1 anti-LAK activity, has potential applications in cancer immunotherapy and tumor prognosis. (+info)Pegylated liposomal doxorubicin as a chemotherapeutic agent for treatment of canine transmissible venereal tumor in murine models. (3/28)
The effectiveness of Doxil as a new chemotherapeutic agent against canine transmissible venereal tumor was evaluated, using NOD/ SCID and CD1-nu xenograft mouse models and the response between the two mouse strains was compared. Samples of xenografted venereal tumor were inoculated SC into 20 six week-old NOD/SCID mice and 20 six week-old CD1-nu mice. Seven weeks later, tumor-bearing mice were divided into treatment and control groups. Treatment group was injected with Doxil (6 mg/kg, IP, as a single injection). Control group was injected with buffered saline (0.75cc, IP). Tumor size was determined by caliper measurements and tumor response was assessed according to standard criteria. In both strains there was a significant decrease in tumor size in response to Doxil treatment (P<0.0001). In CD1-nu eight out of nine tumors (88%) responded to the treatment, and in 2 cases complete remission was observed. In NOD/SCID group response to the treatment was seen in eight out of ten tumors (80%) but none regressed fully. Response to the treatment was statistically equal in both strains even though the apoptotic rate, confirmed by TUNEL staining, was higher in NOD/SCID than in CD-1-nu (8.65% and 0.7%, respectively) and tumor infiltrating cells were different: eosinophils in NOD/SCID and CD45R-positive B lymphocytes, and plasma cells in CD-1-nu. In untreated CD1-nu mice, tumor progress was slower than in NOD/SCID. Our results indicate that Doxil is effective against CTVT in mouse xenograft models. (+info)Identity of rearranged LINE/c-MYC junction sequences specific for the canine transmissible venereal tumor. (4/28)
The canine transmissible venereal tumor is a naturally occurring neoplastic disease that affects the external genitalia of both sexes and is transmitted during coitus. Cytogenetic and immunologic studies demonstrated that tumors from different parts of the world are very similar, suggesting that they are transferred from one animal to another by the transplantation of viable cells. We found that the c-MYC oncogene was rearranged in this tumor by the insertion of a transposable genetic element sequence (known as LINE, long interspersed element) 5' to the first exon. The amplification of a DNA segment located in the junction of the LINE genome and c-MYC upstream sequences enabled the testing of the similarity of transmissible venereal tumor samples collected independently in different parts of the world. Oligonucleotide primers flanking the LINE/c-MYC junction were used to amplify a 340-base-pair segment and nested primers amplified a 280-base-pair segment. A fifth oligonucleotide used as a probe contained the actual junction sequence. All of the tumors analyzed revealed the existence of the specific bands, which were absent in normal canine DNA samples. The amplified segments obtained from all of the tumors analyzed were identical in size and nucleotide sequence, suggesting transmission of the original rearranged cell itself, as opposed to independent events of LINE insertion in a "hot spot." (+info)Disseminated transmissible venereal tumor in a dog. (5/28)
Transmissible venereal tumor (TVT) is a well-documented transplantable tumor in dogs, with no breed or sex predilection and a low metastatic rate. In this report, a 2-year-old intact female Mastiff that had numerous, rapidly growing masses throughout the subcutis mainly at the dorsal body plane, the caudal half of the ventral abdomen, and around the vulva was euthanized due to poor prognosis. Neoplastic nodules similar to those seen in the subcutis were also noted in the lung, anterior mediastinum, liver, spleen, kidney, and superficial and deep lymph nodes in both abdominal and thoracic cavities. The neoplastic nodules from the subcutis as well as metastatic foci revealed similar cytologic and histologic features, which were consistent with canine TVT. By immunohistochemical staining, the neoplastic cells were positive for lysozyme and vimentin but were negative for cytokeratin, desmin, CD3, and CD79a. The diagnosis of the TVT was further supported by the identification and analysis of long interspersed nuclear elements (LINE) from paraffin-embedded tumor tissue. This case is a rare example of TVT with multiorgan metastasis. In this case, the polymerase chain reaction technique was useful in differential diagnosis of canine round cell tumors because this technique can be applied in retrospective as well as future study. (+info)The singular history of a canine transmissible tumor. (6/28)
In this issue of Cell, Murgia et al. (2006) confirm that the infectious agent of canine transmissible venereal tumor is the cancer cell itself and that the tumor is clonal in origin. Their findings have implications for understanding the relationship between genome instability and transmissible cancer and for conservation biology, canine genomics, and companion animal medicine. (+info)Clonal origin and evolution of a transmissible cancer. (7/28)
The transmissible agent causing canine transmissible venereal tumor (CTVT) is thought to be the tumor cell itself. To test this hypothesis, we analyzed genetic markers including major histocompatibility (MHC) genes, microsatellites, and mitochondrial DNA (mtDNA) in naturally occurring tumors and matched blood samples. In each case, the tumor is genetically distinct from its host. Moreover, tumors collected from 40 dogs in 5 continents are derived from a single neoplastic clone that has diverged into two subclades. Phylogenetic analyses indicate that CTVT most likely originated from a wolf or an East Asian breed of dog between 200 and 2500 years ago. Although CTVT is highly aneuploid, it has a remarkably stable genotype. During progressive growth, CTVT downmodulates MHC antigen expression. Our findings have implications for understanding genome instability in cancer, natural transplantation of allografts, and the capacity of a somatic cell to evolve into a transmissible parasite. (+info)Biphasic pulses enhance bleomycin efficacy in a spontaneous canine genital tumor model of chemoresistance: Sticker sarcoma. (8/28)
(+info)Venereal tumors in veterinary medicine refer to a type of contagious cancer that affects primarily the genitalia of dogs and other canids. These tumors are transmitted through sexual contact or during breeding, and they can also spread through direct contact with tumor cells, such as during licking or biting of the affected area.
The tumors typically appear as firm, nodular masses in the genital region, and they can vary in size from small bumps to large, ulcerated lesions. They are highly vascular, which means that they have a rich blood supply, and this can make them prone to bleeding.
Venereal tumors in dogs are treatable with chemotherapy or radiation therapy, and the prognosis is generally good if the tumors are detected and treated early. However, if left untreated, venereal tumors can grow and spread to other parts of the body, making them more difficult to treat and potentially life-threatening.
It's important to note that venereal tumors are not common in domestic pets other than dogs, and they are rarely seen in cats or other small animals.
There is no medical definition for "dog diseases" as it is too broad a term. However, dogs can suffer from various health conditions and illnesses that are specific to their species or similar to those found in humans. Some common categories of dog diseases include:
1. Infectious Diseases: These are caused by viruses, bacteria, fungi, or parasites. Examples include distemper, parvovirus, kennel cough, Lyme disease, and heartworms.
2. Hereditary/Genetic Disorders: Some dogs may inherit certain genetic disorders from their parents. Examples include hip dysplasia, elbow dysplasia, progressive retinal atrophy (PRA), and degenerative myelopathy.
3. Age-Related Diseases: As dogs age, they become more susceptible to various health issues. Common age-related diseases in dogs include arthritis, dental disease, cancer, and cognitive dysfunction syndrome (CDS).
4. Nutritional Disorders: Malnutrition or improper feeding can lead to various health problems in dogs. Examples include obesity, malnutrition, and vitamin deficiencies.
5. Environmental Diseases: These are caused by exposure to environmental factors such as toxins, allergens, or extreme temperatures. Examples include heatstroke, frostbite, and toxicities from ingesting harmful substances.
6. Neurological Disorders: Dogs can suffer from various neurological conditions that affect their nervous system. Examples include epilepsy, intervertebral disc disease (IVDD), and vestibular disease.
7. Behavioral Disorders: Some dogs may develop behavioral issues due to various factors such as anxiety, fear, or aggression. Examples include separation anxiety, noise phobias, and resource guarding.
It's important to note that regular veterinary care, proper nutrition, exercise, and preventative measures can help reduce the risk of many dog diseases.
I believe there might be a misunderstanding in your question. "Dogs" is not a medical term or condition. It is the common name for a domesticated carnivore of the family Canidae, specifically the genus Canis, which includes wolves, foxes, and other extant and extinct species of mammals. Dogs are often kept as pets and companions, and they have been bred in a wide variety of forms and sizes for different purposes, such as hunting, herding, guarding, assisting police and military forces, and providing companionship and emotional support.
If you meant to ask about a specific medical condition or term related to dogs, please provide more context so I can give you an accurate answer.
Veterinary medicine is the branch of medical science that deals with the prevention, diagnosis, and treatment of diseases, disorders, and injuries in non-human animals. The profession of veterinary medicine is dedicated to the care, health, and welfare of animals, as well as to the promotion of human health through animal research and public health advancements. Veterinarians employ a variety of diagnostic methods including clinical examination, radiography, laboratory testing, and ultrasound imaging. They use a range of treatments, including medication, surgery, and dietary management. In addition, veterinarians may also advise on preventative healthcare measures such as vaccination schedules and parasite control programs.
Veterinary education is a postsecondary educational process and training that prepares students to become licensed veterinarians. The curriculum typically includes courses in biochemistry, anatomy, physiology, pharmacology, pathology, microbiology, immunology, toxicology, animal nutrition, parasitology, and veterinary clinical practice.
In addition to classroom instruction, veterinary education also involves hands-on training through clinical rotations in veterinary hospitals, clinics, and research laboratories. Students learn how to diagnose and treat diseases and injuries in a variety of animals, including domestic pets, livestock, and wildlife.
Veterinary education typically takes four years to complete and is offered by colleges or schools of veterinary medicine that are accredited by the American Veterinary Medical Association (AVMA) Council on Education. After completing their education, graduates must pass a licensing exam in order to practice veterinary medicine. Continuing education is also required throughout their careers to maintain their license and stay up-to-date with advances in the field.
Veterinary drugs, also known as veterinary medicines, are substances or combinations of substances used to treat, prevent, or diagnose diseases in animals, including food-producing species and pets. These drugs can be administered to animals through various routes such as oral, topical, injectable, or inhalation. They contain active ingredients that interact with the animal's biological system to produce a therapeutic effect. Veterinary drugs are subject to regulatory control and must be prescribed or recommended by a licensed veterinarian in many countries to ensure their safe and effective use.