Genetic testing for personalised medicine and limitations of the current medical practise in public health
Ben Y.F. Fong, Martin C.S. Wong in The Routledge Handbook of Public Health and the Community, 2021
Many diseases are caused by infectious microorganisms, such as Epstein-Barr Virus (EBV) which has a high correlation with the development of nasopharyngeal cancer (Hau et al., 2020), while Helicobacter pylori has been proven a causative agent of stomach ulcer and cancer (Choi et al., 2020). Hence, early detection of these microorganisms in human body leading to early treatment of these diseases can, very often, improve the medical outcome. A study has shown that sequencing of the DNA in human serum allows detection of viral DNA, such as EBV, which can be used as a screening test for nasopharyngeal cancer in the general population (Lam et al., 2018). In the future, it is possible to identify tens of thousands of microorganisms in blood in a single sequencing screening. Thanks to the exponential growth in the development of the sequencing technology, the cost of a whole genome sequencing has been dramatically reduced to approximately US$7000–10,000 (Bick et al., 2017). As this reliable technology becomes more affordable, it is anticipated that WGS will become more accessible to patients in the future.
Nasal Cavity Cancer in Laboratory Animal Bioassays of Environmental Compounds
D. V. M. Gerd Reznik, Sherman F. Stinson in Nasal Tumors in Animals and Man, 2017
Other occupational or environmental groups with increased exposure to agents known to induce nasal neoplasms in laboratory animals are also predisposed to nasal epithelial carcinogenesis. Inhalation of cigarette smoke is associated with respiratory carcinogenesis in humans and some studies have also shown an increased risk of heavy smokers for the development of nasal cancers.58 Wood workers have an unusually high incidence of nasal tumors.61 Trimethoxycinnamaldehyde, a derivative of wood lignin constituents, was a nasal carcinogen in rats. Several occupational groups exposed to inorganic dusts (such as nickel workers) have increased incidences of nasal cavity cancer. Experimental exposure to several dusts has been associated with nasal epithelial carcinogenesis in animals (see Chapter 10, Volume II). Southern Chinese carry a high risk for nasopharyngeal cancer.58 Consumption of large quantities of marine salted fish has been suggested as an etiologic agent. Cantonese salted fish was a nasal carcinogen in rats. Radiation has been implicated in the genesis of nasal cancers in man.62 Radioactive cerrium induced nasal carcinomas in rats (also see Chapter 6).
Head and neck cancer
Pat Price, Karol Sikora in Treatment of Cancer, 2014
There are wide geographical variations in the standardized incidence rates for specific types of head and neck cancer. Bangladesh, one of the poorest countries in the world, has some of the highest incidence rates of head and neck tumours. These differences provide important clues concerning the causes of the disease and the role of genetic susceptibility in the development of cancer. The distribution of nasopharyngeal cancer is a case in point. The highest incidence is in Hong Kong and Southeast Asia, with world age-standardized rates per 100,000 men of 25.2 in Hong Kong, 15.8 in Singapore and 13.4 in Malaysia. The incidence of this cancer is also high in parts of North Africa—10.9 in Tunisia—where, both clinically and epidemiologically, it presents as a distinct form of the disease.
Factors associated with early diagnosis in pediatric vs adult nasopharyngeal carcinoma
Published in Acta Oto-Laryngologica, 2018
In recent years, the epidemiological study of NPC has been extensively described in the literature, as well as pathogenesis, treatment and prognosis. However, cancer of the nasopharynx often evades early diagnosis. The nasopharynx is a relatively difficult area to examine. Symptoms of NPC are often of insidious onset and may be ignored in the early stages, especially in children and adolescents. A better characterization of the disease as it relates to the different age groups is critical to optimize diagnosis and treatment approaches. This is particularly important since treatment for pediatric NPC usually follows the guidelines established for adults, and the potential differences in pathogenesis. Furthermore, children and adolescents with cancer are classically excluded from clinical trials, which target diseases that are more prevalent in adults. Comparing the clinical features of children and adolescents and adults may provide clues to differences in pathogenesis between these groups and may also assist in bringing about collaboration among medical and pediatric oncologists in the design of future trials [6]. The purpose of this article is to statistics the initial symptoms of children with nasopharyngeal cancer and compared with adults, leading to a further understanding of the disease. Diagnosis of NPC at early stage can improve the outcome of NPC patients. Therefore, there is a clear need for early diagnosis.
The value of serum p53 antibody as a biomarker in oral and pharyngeal squamous cell carcinoma
Published in Acta Oto-Laryngologica, 2023
Shotaro Hirokawa, Koji Araki, Taku Yamashita, Kosuke Uno, Masayuki Tomifuji, Hideaki Shimada, Akihiro Shiotani
The carcinogenic mechanism of p16-positive oropharyngeal cancer is characterized by deregulated human papillomavirus (HPV) E6 and E7 oncoprotein expression in proliferating cells [16]. E6 and E7 inactivate p53 and RB, respectively, resulting in the disruption of cell cycle regulation and inhibition of p53‑mediated apoptotic responses, driving immortalization, and the accumulation of epigenetic and genetic alterations necessary for cancer progression. Nasopharyngeal cancer is caused by the Epstein-Barr virus (EBV), which is a persistent infection of the pharyngeal mucosa. EBV-encoded proteins, including latent membrane protein 1 (LMP1), LMP2A, and EBV nuclear antigen 1 cause dysregulation of intracellular signaling pathways in nasopharyngeal cancer cells [17]. These facts indicate that the oncogenic mechanism of virus-related cancer is independent of p53 gene mutations, and it is also related to the small number of TP53 mutations shown in HPV-related cancers in the TCGA study [14]. Therefore, autoantibodies against mutant p53 protein are not produced in patients with virus-related pharyngeal cancer, and our results support this.
A model of radiation-induced temporomandibular joint damage in mice
Published in International Journal of Radiation Biology, 2022
Peng Zhang, Lejing Yao, Guoping Shan, Yuanyuan Chen
The incidence of nasopharyngeal carcinoma is higher in Southern China than that in the other regions of China (Eduardo et al. 2010). Because of the nasopharyngeal anatomical location and radiological characteristics, radiotherapy has become the primary treatment for nasopharyngeal carcinoma; however, this treatment has some serious side effects, including impaired function of the salivary gland, masticatory muscle fibrosis, limited jaw mobility, etc. (Ritchie et al. 1983). Restricted jaw mobility is a common sequelae of nasopharyngeal carcinoma patients after radiotherapy, with incidence rates of 5–58.5% (Chen et al. 2001; Dijkstra et al. 2004). However, no experiments have revealed the specific mechanism of jaw movement, with current literature mainly comprising clinical case reports. Some authors have reported a relationship between fibrosis of the temporomandibular joint (chewing muscles) after high-dose irradiation and limited jaw movement (Goldstein et al. 1999; Forrester et al. 2014). This clinical side effect has been dynamically linked to some proinflammatory cytokines, chemokines, and other specific molecular substances (Hallahan et al. 2002). Prospective studies using imaging and those investigating the pathology and changes in the microenvironment caused by radiofrequency injury of temporomandibular joint will have a positive effect on the treatment and prevention of such injuries.
Related Knowledge Centers
- Diet
- Epidemiology
- Epithelium
- Head & Neck Cancer
- Pharyngeal Recess
- Pharynx
- Virus
- Cancer
- Head & Neck Cancer
- Genetics
- Squamous-Cell Carcinoma