human her2 female breast cancer cell lines bt474 ts  (ATCC)

Journal: Journal of Nuclear Medicine

Article Title: Preirradiation of Spheroids with 225 Ac-Trastuzumab Improves Penetration of 225 Ac-Liposomes and MIRDcell Predictions of Responses to Drug Cocktails

doi: 10.2967/jnumed.124.269273

Figure Lengend Snippet: Penetration data in BT474 spheroids (200-µm radius) for Alexa Fluor 647-NHS-trastuzumab ( ), CFDA-SE liposomes ( ), and CFDA-SE liposomes after preirradiating spheroids with 6.5 kBq/mL 225 Ac-trastuzumab ( ). Shown are time-integrated average concentrations as function of distance from centers of spheroids (A) and correlated mean decays per cell using activity concentrations of 6.875 kBq/mL for all drugs (calculated with MIRDcell-Ã) (B). Distances beyond 200 µm represent medium.

Article Snippet: The spheroids comprised the human epidermal growth factor receptor 2–positive human BT474 breast cancer cell line, obtained from the American Type Culture Collection.

Techniques: Liposomes, Activity Assay

Journal: Journal of Nuclear Medicine

Article Title: Preirradiation of Spheroids with 225 Ac-Trastuzumab Improves Penetration of 225 Ac-Liposomes and MIRDcell Predictions of Responses to Drug Cocktails

doi: 10.2967/jnumed.124.269273

Figure Lengend Snippet: MIRDcell calculated mean decays per cell attributed to liposomes in BT474 spheroids based on experimental CFDA-SE liposome penetration data for (100% 225 Ac-liposome case from Howe et al. ) and (50% 225 Ac-liposome, 50% 225 Ac-trastuzumab case from newly retrieved data), and extrapolated/averaged (weighted) liposome penetration data for (70% 225 Ac-liposome, 30% 225 Ac-trastuzumab case) and (30% 225 Ac-liposome, 70% 225 Ac-trastuzumab case).

Article Snippet: The spheroids comprised the human epidermal growth factor receptor 2–positive human BT474 breast cancer cell line, obtained from the American Type Culture Collection.

Techniques: Liposomes

Journal: Journal of Nuclear Medicine

Article Title: Preirradiation of Spheroids with 225 Ac-Trastuzumab Improves Penetration of 225 Ac-Liposomes and MIRDcell Predictions of Responses to Drug Cocktails

doi: 10.2967/jnumed.124.269273

Figure Lengend Snippet: Comparison of BT474 experimental outgrowths taken from Howe et al. to MIRDcell (version 4.14)-predicted SFs as bar plot (A), linear regression plot (B), and Bland–Altman plot (C) (95% limit of agreement, −0.048 to 0.095). Predicted SFs shown were based on 225 Ac-trastuzumab in spheroids with no 225 Ac daughters present and 225 Ac-liposomes in spheroids with 225 Ac daughters present. 225 Ac-trastuzumab and 225 Ac-liposomes in medium both had 225 Ac daughters present. Bars on abscissa of panel A and legend for panels B and C are labeled to denote percentage of activity corresponding to 225 Ac-liposomes and 225 Ac-trastuzumab. For example, “L-100, A-0” is 100% 225 Ac-liposomes and 0% activity on trastuzumab antibodies. Error bars for experimental outgrowths correspond to SD. Final prediction uses penetration data for CFDA-SE liposomes after spheroids are exposed to 6.5 kBq/mL 225 Ac-trastuzumab for 50%/50% case; 70% and 30% 225 Ac-liposome cases use extrapolated/averaged penetration data shown in . For CFDA-SE liposomes, published penetration data that were used for old prediction did not involve pretreatment 225 Ac-trastuzumab. Only final predictions are shown in panels B and C.

Article Snippet: The spheroids comprised the human epidermal growth factor receptor 2–positive human BT474 breast cancer cell line, obtained from the American Type Culture Collection.

Techniques: Comparison, Liposomes, Labeling, Activity Assay

Journal: Journal of Nuclear Medicine

Article Title: Preirradiation of Spheroids with 225 Ac-Trastuzumab Improves Penetration of 225 Ac-Liposomes and MIRDcell Predictions of Responses to Drug Cocktails

doi: 10.2967/jnumed.124.269273

Figure Lengend Snippet: Mean absorbed dose due to 225 Ac-trastuzumab (antibodies) and 225 Ac-liposomes (liposomes) in BT474 spheroids and medium for cells at various radial depths within 200-µm-radius spheroids (top). Below each graph, corresponding MIRDcell 3D slice representation of spheroid is shown for equatorial slices of spheroids. Dark red dots in equatorial slices represent living cells, whereas pink dots represent dead cells.

Article Snippet: The spheroids comprised the human epidermal growth factor receptor 2–positive human BT474 breast cancer cell line, obtained from the American Type Culture Collection.

Techniques: Liposomes

Journal: Journal of Nuclear Medicine

Article Title: Preirradiation of Spheroids with 225 Ac-Trastuzumab Improves Penetration of 225 Ac-Liposomes and MIRDcell Predictions of Responses to Drug Cocktails

doi: 10.2967/jnumed.124.269273

Figure Lengend Snippet: MIRDcell (version 4.16) AI–predicted minimum number of decays necessary to achieve target SF < 0.0001 in BT474 spheroids treated with 225 Ac-trastuzumab (antibodies), 225 Ac-liposomes (liposomes), or combination thereof. 225 Ac daughters were assumed to migrate away from 225 Ac-trastuzumab and to remain near 225 Ac-liposomes within spheroid. MIRDcell AI was limited to maximum molar activity of 10 6 GBq/mol for both drugs and lower limit of 1.17 × 10 5 GBq/mol for antibodies only. No bar appearing for antibodies indicates that 225 Ac-trastuzumab alone could not achieve target SF. When optimized molar activities for combined therapy and liposome-only therapy were checked in Monte Carlo–based MIRDcell simulation, zero cell survivors were achieved for both therapies although liposomes required more total decays to achieve same result. “Liposome with preirradiation” indicates use of penetration profiles after preirradiation with 225 Ac-trastuzumab as in 50%/50% case, and “Liposome without preirradiation” indicates use of liposome penetration profile without preirradiation as in 100% 225 Ac-liposomes case.

Article Snippet: The spheroids comprised the human epidermal growth factor receptor 2–positive human BT474 breast cancer cell line, obtained from the American Type Culture Collection.

Techniques: Liposomes, Activity Assay