Esophageal cancer in Kashmir [India]: an enigma for researchers

About 90% of esophageal cancers worldwide are Squamous Cell Carcinomas [SCC], mostly occurring in defined high-incidence areas of low and middle-resource countries. Historically, the highest incidences are reported in regions of Central Asia. One such region is Kashmir Valley in Northern India. In this review, we summarize a large body of epidemiological, toxicological and observational information on occurrence, dietary patterns and lifestyles to discuss factors that may be involved in the etiology of SCC in Kashmir Valley. To date, no single factor can be identified as the main cause of the excess incidence of SCC as compared to other regions of India. Three main components emerge as important factors: a societal component with poor, rural lifestyle and general deprivation, status in particular in vitamins and oligoelements; a lifestyle component with the use of copper utensil in cooking, the consumption of spicy, deep fried foodstuffs, and the drinking of hot salty tea; and an environmental component with exposure to high levels of dietary nitrosamines from diverse sources. Overall, these three components are similar to the general pattern of factors that have been involved in causing SCC in other high-incidence area in the so-called "esophageal cancer belt", namely in central China [Cixian, Lixian] and in Northern Iran [Golestan]. Further comparative studies between these regions are needed to identify the contributions of these various components

Association of Beta-catenin gene mutations and human papillomavirus in Carcinoma of Esophagus in a high-risk population of India

Background: Esophageal cancer [EC] is the sixth leading cause of death from cancer. In high-risk regions, squamous cell carcinoma is the most common type of EC, and its etiology remains poorly understood. It shows uneven geographical distribution in its occurrence, reflecting the influence of local environmental conditions, lifestyle and genetic predisposition in the development of the cancer. Kashmir, in the north of India, has been described as a high-risk area for esophageal squamous cell carcinoma [ESCC]. In the present investigation an attempt was made to study the role of -catenin mutations and human papillomavirus in 62 ESCC patients from Kashmir

Methods: The hot spot mutation region of -catenin exon 3 was evaluated in matched tumor and normal tissues using a combination of PCR-SSCP and direct sequencing. We used two different sets of consensus primers viz., GP5+ and GP6+; PGMY09 and PGMY11 in conjunction with reverse line blot assay to screen for human papillomavirus[HPV]

Results: None of the tumors showed the presence of commonly reported mutations in -catenin. In view of the fact that HPV has been linked to pathogenesis of EC, we screened all the tumor and control specimens for the presence of HPV and we didn't detect HPV in any of the matched tumor and control specimens in contrast to the positive controls we used

Conclusion: In conclusion our results suggest that squamous cell carcinoma of esophagus in Kashmir may arise independent of oncogenic Beta-catenin mutations and HPV is unlikely to be an etiologic factor for ESCC in this region

association of beta-catenin gene mutations and human papillomavirus in carcinoma of esophagus in a high-risk population of India

Esophageai cancer [EC] is the sixth leading cause of death from cancer. In high-risk regions, squamous cell carcinoma is the most common type of EC, and its etiology remains poorly understood. It shows uneven geographical distribution in its occurrence, reflecting the influence of local environmental conditions, lifestyle and genetic predisposition in the development of the cancer. Kashmir, in the north of India, has been described as a high-risk area for esophageal squamous cell carcinoma [ESCC]. In the present investigation an attempt was made to study the role of p-catenin mutations and human papillomavirus in 62 ESCC patients from Kashmir. The hot spot mutation region of p-catenin exon 3 was evaluated in matched tumor and normal tissues using a combination of PCR-SSCP and direct sequencing. We used two different sets of consensus primers viz., GP5+ and GP6+; PGMY09 and PGMY11 in conjunction with reverse line blot assay to screen for human papillomavirus [HPV]. None of the tumors showed the presence of commonly reported mutations in p-catenin. In view of the fact that HPV has been linked to pathogenesis of EC, we screened all the tumor and control specimens for the presence of HPV and we didn't detect HPV in any of the matched tumor and control specimens in contrast to the positive controls we used. In conclusion our results suggest that squamous cell carcinoma of esophagus in Kashmir may arise independent of oncogenic p-catenin mutations and HPV is unlikely to be an etiologic factor for ESCC in this region