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Echinococcosis is a zoonosis caused by cestodes of the genus Echinococcus (family Taeniidae). This serious and near-cosmopolitan disease continues to be a significant public health issue, with western China being the area of highest endemicity for both the cystic (CE) and alveolar (AE) forms of echinococcosis. Considerable advances have been made in the 21st century on the genetics, genomics, and molecular epidemiology of the causative parasites, on diagnostic tools, and on treatment techniques and control strategies, including the development and deployment of vaccines. In terms of surgery, new procedures have superseded traditional techniques, and total cystectomy in CE, ex vivo resection with autotransplantation in AE, and percutaneous and perendoscopic procedures in both diseases have improved treatment efficacy and the quality of life of patients. In this review, we summarize recent progress on the biology, epidemiology, diagnosis, management, control, and prevention of CE and AE. Currently there is no alternative drug to albendazole to treat echinococcosis, and new compounds are required urgently. Recently acquired genomic and proteomic information can provide a platform for improving diagnosis and for finding new drug and vaccine targets, with direct impact in the future on the control of echinococcosis, which continues to be a global challenge., (Copyright © 2019 American Society for Microbiology.)

In the first part of this review, some behavioural and environmental risk factors playing important roles in the development of Kazakh's oesophageal squamous cell carcinoma (OSCC) were presented. Although all individuals have been exposed to the same environment and share the same behaviour, some of them will not develop OSCC. Thus, gene susceptibility and/or gene polymorphism are unavoidably involved. The molecular events underlying the initiation and progression of OSCC remain, however, poorly understood. In the second part of our review of OSCC in northwestern China, especially in the high-risk Kazakh population, some recent progress in the study of the molecular biology underlying oesophageal carcinogenesis, including chromosome deletions and loss of heterozygocity, polymorphisms of genes involved in xenobiotic metabolizing and DNA repair, and genetic alterations of transcriptional factors and apoptosis genes are presented. Results obtained in this high-risk population are compared with those obtained in other areas that are also known to be at high risk for OSCC, and whenever possible, with those studies performed in European, American or Australian low-risk areas. Recent advances in the investigation of the proteomics and microRNA biomarkers potentially useful for an earlier diagnosis and/or prognosis of OSCC are also discussed.

Oesophageal squamous cell carcinoma (OSCC) remains a public health problem in many countries, especially in emerging and developing countries. Epidemiology of OSCC is characterized by marked differences in prevalence between countries/regions/ethnical groups. The highest incidence in the world is reached by populations living in specific areas of northwestern Xinjiang, China where age-adjusted mortality may reach 150 of 100 000. In fact, there are also marked differences among the various geographical areas and the various ethnic groups within the region, which suggests specific risk factors. Behavioural factors include those factors which are common to all 'high-risk populations', such as tobacco smoking and alcohol drinking. However, the very unusual sex ratio (1.2 : 1.0) and young age range of OSCC occurrence suggests the involvement of additional early risk factors shared by males and females, and which are different from those studied in other 'high-risk' areas of the world, including China, such as LinXian area. These include drinking very hot and salted tea, boiled with milk; a diet rich in meat, especially salted, dry and/or smoked meat, and dairy products; and a diet poor in fresh fruit and vegetables. The combination of hot drinks (such as milk, tea and soups) and high-degree spirit drinks, and hard food (bread, meat and cheese), together with poor oral hygiene and tooth loss, is likely to add mechanical injury of the oesophagus to other factors linked to climate characteristics of the area (drought) and dietary habits, which promote a sodium and nitrosamine-rich diet. Association of early and severe hypertension in the same populations at high risk of OSCC might likely raise more attention. Human papilloma virus (HPV) infection, and especially HPV 16/18 E6/E7, with gene mutations and association with p53 overexpression, may contribute to the extremely high incidence of OSCC observed in Xinjiang, and could be accessible to prevention. Infection may especially be a crucial additional factor in the Uygur population in which not only HPV infection but also infection with other oncogenic viruses, such as HHV8, are highly prevalent. Genetic polymorphism might interact with viruses and/or viral products to promote carcinogenesis. These observations in northwestern China suggest that usually neglected factors, such as sodium excess and viral infection, could be taken into more account when studying OSCC risk factors in other parts of the world, especially Europe.