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SUMMARY:Nanostructural study of human tumour transformed tissues by X-ray 
 diffraction methods using synchrotron radiation
DTSTART;VALUE=DATE-TIME:20160705T090000Z
DTEND;VALUE=DATE-TIME:20160705T100000Z
DTSTAMP;VALUE=DATE-TIME:20260411T052622Z
UID:indico-contribution-1184@indico.inp.nsk.su
DESCRIPTION:Speakers: Alvina Vazina (Institute of theoretical and experime
 ntal biophysics\, RAS)\nThe work is dedicated to investigating the nanostr
 uctural organization of proteoglycans in different physiological states of
  biological tissues of human and animals. \nExperimental samples of human 
 tissues obtained during biopsies\, surgeries and pathologoanatomic revisio
 ns\; samples of breast cancer tissue were obtained from mammary gland divi
 sion of Blokhin’s Onkological Scientific Center of Russian Ministry of H
 ealth. We used also unique collection of tumor transformed epithelial tiss
 ues from respiratory tracts of liquidators engaged in elimination of the d
 isaster sequels on the Chernobyl A-plant obtained from Pulmonogical Resear
 ch Institute. X-ray diffraction and fluorescence study of biological tissu
 es with using synchrotron radiation were carried out on the channel K1.3 o
 f the “Siberia-2” storage ring at NRC “Kurchatovsky Institute”\, M
 oscow (on the constructed and created by us small-angle stations DICSI) an
 d on the channel 3b of VEPP-3 at INP SD RAS\, Novosibirsk\, and also on SA
 XS/WAXS station of European Synchrotron Radiation Facility at Grenoble\, F
 rance.\nSmall-angle X-ray patterns of epithelial tissue\, both intact and 
 pathologically transformed\, display a large number of sharp diffraction r
 ings at spacing of 4.5 nm and its higher orders caused by the proteoglycan
 s of extracellular matrix of tissue. The period of identity at spacing of 
 4.65 (± 0.15) nm is attributed by us to regular attachment of olygosaccha
 ride chains to the protein core of giant proteoglycan molecules [A.A.Vazin
 a et al.\, NIM\, 2005\, A543\, 297-301]. A correlation between the integra
 ted intensity of X-ray patterns and elemental content of tissue is observe
 d. It is experimentally shown that the structure of proteoglycans can be r
 eversibly transformed by metal cations and chelating agents\, and that cal
 cium is the major element in the mineral composition of tissue.\nIn cancer
  transformed tissues intensity of diffuse scattering and diffraction rings
  of 4.5 nm varies in a wide range and correlates with change of calcium co
 ntent in the diseased tissues\, a significant change in elemental content 
 is detected\, up to 200 times increase in the concentration of calcium is 
 found. The final stage of disease is characterized by a significant increa
 se in small-angle diffuse scattering\; Debye rings are never registered. T
 reating the tissue with chelating agents such as EGTA and EDTA\, in this c
 ase turns out to be ineffective\, suggesting the irreversibility of the st
 ructural transformation of the extracellular matrix.\nThus\, the problem o
 f cancerogenesis should be looked at in two aspects: investigation of the 
 mechanisms of normal cell transformation which is initiated by DNA damage 
 (mutations)\, and the stages of tumor progression\, processes of malignant
  cell proliferation\, invasion and metastasis which lead to numerous malig
 nant tumors. X-ray study of tissues indicates that it may be possible to u
 se diffraction characteristics of proteoglycan structures as novel markers
  of pathological transformation of tissues.\nThe research was supported by
  RFBR-Moscow region Grant #14-44-03667.\n\nhttps://indico.inp.nsk.su/event
 /3/contributions/1184/
LOCATION:Budker INP 2nd and 3rd floors
URL:https://indico.inp.nsk.su/event/3/contributions/1184/
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