br Silica is not a
Silica is not a mutagen and might not be an initiator in the multi-stage carcinogenesis process. More likely, the silicified prickles are the critical promoters while initiating agent exposure such as polycyclic aromatic hydrocarbons and background radiation can be ubiquitous. These silica prickles can cause repeated local injury as they pass down the esophagus and stimulate proliferation by providing anchorage (O'Neill et al., 1982). Indeed, biogenic silica fibers were found to be powerful promoters of skin cancer in mice (Bhatt et al., 1984). The mechanism by which these silica fibers stimulate cell growth and di-vision is not completely understood. Besides population based geo-graphical studies, mechanistic insights can be obtained by testing the carcinogenicity of silicified prickles from the wheat chaﬀ in north China using human cell models and chicken models.
In conclusion, our preliminary findings on the detection of phyto-liths and the higher than normal Si concentration in ESCC tumor tissue
Fig. 3. Transmission 1809249-37-3 micrographs and elemental analysis (by EDS) of particles from freeze dried ash of the resected esophagus tissue of an ESCC patient from north China. A) Sharp signals of Si were seen in the tumor tissue. Elemental signals of P and Ca were also obvious, indicating tissue calcification by calcium-phosphate deposition. B) Si signal was not obvious in the normal tissue besides the esophageal carcinoma.
warrants further testing the role of biogenic silica in esophageal cancer. Both population and laboratory-based studies involving multiple dis-ciplines are needed to examine whether silicified prickle hairs from wheat chaﬀ might contaminate wheat flour and contribute to the high incidence of ESCC in north China.
Ethics approval and consent to participate
Ethical approval for this study was obtained from the Institutional Review Board of Heping Hospital (2018-004).
Consent for publication
This study contained no individual person's data in any form.
Availability of data and material
Please contact author for data requests.
The authors declare that they have no competing interests.
The National Natural Science Foundation of China [grant numbers 41272180 and 41771241] partially supported Linwei Tian and Xinxin Zuo, respectively for their time in writing this manuscript.
CL and LT conceived and designed the analysis; SX and JR collected data; WL, JZ, ZH and XZ performed phytolith and microscope analyses; LT wrote the paper.
Fig. 4. Transmission electron micrograph and elemental analysis (by EDS) of mineral particles in ultrathin section of the resected esophagus tissue of an ESCC patient from north China. Sharp signals of Si in the EDX spectrum were seen in the tumor tissue; the Pb peaks were from lead citrate in the TEM grid staining material.
Conflicts of interest
We have no conflict of interest to declare.
This study was supported by the National Natural Science Foundation of China [grant numbers 41272180 and 41771241]. We thank Prof. Houyuan Lu from the Institute of Geology and Geophysics, Chinese Academy of Sciences for his advice and laboratory support.
Appendix A. Supplementary data
Craddock, V.M., 1993. Cancer of the Esophagus: Approaches to the Etiology. Cambridge University Press.
Silica accumulation in Triticum aestivum L. and Dactylis glomerata L. Anal. Bioanal.
Editorial Committee for the Atlas of Cancer Mortality in the People’s Republic of China, 1979. Atlas of Cancer Mortality in the People's Republic of China. China Map Press, Shanghai.
International Agency for Research on Cancer (IARC), 1993. Pickled vegetables. In: IARC Monographs Evaluating the Carcinogenic Risks to Humans. Some Naturally Occurring Substances: Food Items and Constituents, Heterocyclic Aromatic Amines and Mycotoxins, vol. 56. World Health Organization, Geneva, pp. 83–113. Jabbari, A., Besharat, S., Semnani, S., 2008. Role of silica in esophageal cancer. World J.
Van Rensburg, S., 1982. Esophageal cancer, micronutrient malnutrition, and silica frag-ments. Lancet 2, 1098–1099. Van Rensburg, S., 1981. Epidemiologic and dietary evidence for a specific nutritional predisposition to esophageal cancer. J. Natl. Cancer Inst. 67, 243–251.
85 ARTICLE IN PRESS
Available online at www.jpain.org and www.sciencedirect.com
Associations Between Catecholaminergic and Serotonergic Genes and Persistent Arm Pain Severity Following Breast Cancer Surgery
Mitchell R. Knisely,* Yvette P. Conley,y Betty Smoot,z Steven M. Paul,x Jon D. Levine,z and Christine Miaskowskix