Ra. Britten et al., THE DIFFERENTIAL INDUCTION OF COLLATERAL RESISTANCE TO 62.5-MEV (P-]BE-MEV PHOTONS BY EXPOSURE TO CISPLATINUM() NEUTRONS AND 4), International journal of radiation oncology, biology, physics, 26(5), 1993, pp. 837-843
Citations number
18
Categorie Soggetti
Oncology,"Radiology,Nuclear Medicine & Medical Imaging
Purpose: To determine the relative sensitivity to cis-platinum, 4 MeV
photons and 62.5 MeV (p-->Be+) neutrons in five human tumor cell lines
, and their cis-platinum resistant variants. Methods and Materials: Th
e degree of cross-resistance of five human in-vitro cell lines to phot
ons or fast neutrons was analysed for both cisplatinum-sensitive and r
esistant variants. Results: The development of acquired cis-platinum r
esistance conferred collateral resistance to 62.5 MeV (p - Be+) neutro
ns in all five cell lines, but did not consistently decrease the photo
n sensitivity of these same cells. Conclusion: The reduction in photon
and neutron sensitivity following the development of acquired cis-pla
tinum resistance may possibly be regulated by different mechanisms. Th
e reduction in neutron sensitivity was primarily due to a 1.3-1.7 fold
reduction in the magnitude of the initial slope (alpha), which was in
dependent of the degree of platinum resistance induced, suggesting a n
on-stochiometric relationship between the mechanisms responsible for a
cquired cis-platinum, and 62.5 MeV (p-->Be+) neutron resistance.