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Tumor Discovery Sorafenib induces MVPs in NSCLC

as mediator of PAFR-induced effect, 18,19 our next studies both cell lines in a dose-dependent manner as compared
evaluated if sorafenib treatment can induce MVP release. to vehicle control (Figure 2A and B). In addition, we found
Furthermore, as MVP release is an earlier event, which that sorafenib-mediated MVP release was comparable to
significantly peaks at 4 – 8 h time points, and could CPAF and PMA treatments (Figure 2A and B).
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impact tumor cell behavior in responses to therapeutic As PAFR activation mediates MVP release, and the
agents, we tested three different doses (4, 8, and 16 aSMase is a key mediator of MVP biogenesis, our
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µM) of sorafenib from the cell viability assay shown in next studies determined the underlying mechanisms,
Figure 1A and 1B, that resulted in differential cytotoxic particularly, the roles of the PAFR signaling and an
response. To that end, A549 and H1299 cell lines were aSMase using the optimal dose (8 µM) of sorafenib. To
separately treated with vehicle (0.1% DMSO) as a negative that end, A549 and H1299 cell lines were pre-treated
control, CPAF (a known PAFR agonist, 100 nM) and PMA with a well-known PAFR antagonist, WEB2086 (10
(PAFR-independent agonist, 100 nM) as positive controls, µM), or an aSMase inhibitor, imipramine (20 µM),
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and various doses of sorafenib. After 4 h, we extracted and followed by the treatments with or without CPAF, PMA,
analyzed MVP as per our published reports. 14,18,19 The data or sorafenib. After 4 h, we extracted and analyzed MVP.
demonstrated that sorafenib induces MVP release from Our studies demonstrated that the WEB2086 compound

A B

Figure 1. Effects of sorafenib on cell survival. (A) Dose response curve of sorafenib effect on A549 cells. (B) Dose response curve of sorafenib effect on
H1299 cell lines. Data are presented as mean ± scanning electron microscope of four independent biological replicates.

A B

Figure 2. Dose-response effect of sorafenib treatment on MVP release. A549 (A) and H1299 (B) cell lines were treated with vehicle (0.1% DMSO), CPAF
(100 nM), PMA (100 nM), and various doses of sorafenib. After 4 h of incubation, MVP extraction and analyses were performed. Data are presented as
mean ± scanning electron microscope of three independent biological replicates, normalized per 1 × 10 cells. Statistically significant differences were
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observed between control and other groups.
Notes: *p<0.05, **p<0.01, ***p<0.001.
Abbreviations: CPAF: Carbamoyl-platelet-activating factor; MVP: Microvesicle particle; PMA: Phorbol myristate acetate; SF: Sorafenib.

Volume 4 Issue 3 (2025) 84 doi: 10.36922/TD025110019