Abstract:
Triple Negative Breast Cancer (TNBC) is highly heterogeneous and an aggressive
breast cancer subtye associated with poor prognosis. TNBC lacks the PR, ER, and
HER2 receptors found in other breast cancer subtypes. Therefore TNBC does not
respond to hormonal therapies targeted towards ER, PR, and HER2, demanding novel
therapies. Chloroquine (CQ) is an anti-malarial drug it exhibits its anti-cancer effects
by sensitizing cancer cells to chemotherapy and inhibiting autophagy. Previously it has
been reported that Beclin-1 which is an autophagy gene contributes to cell invasion,
proliferation, and migration suggesting that Beclin-1 provides proto-oncogenic effects
in TNBC. However, the role of Beclin-1 in mediating CQ-induced anti-tumor effects
in TNBC is not yet known. In this study, in silico data of CD44 and Beclin-1 was
obtained from Gepia, Human Protein Atlas, and STRING. Chloroquine-encapsulated
chitosan nanoparticles coated with Hyaluronic acid (CQ-CS-HA NPs) were formulated
by ionic gelation method. Nanoparticle characterization was done by XRD, FTIR, Zeta,
SEM, and TEM. Afterwards in vitro cytotoxicity and hemolytic activity were analyzed
and Beclin 1 expression in response to treatment was observed. The optimized CQ NFs
had zeta potential, particle size, and encapsulation efficiency of 284.6, 23.5, and 83.0,
respectively. The SEM and TEM analysis showed spherical-shaped nanoformulations
with dense structure and narrow size distribution. The in vitro cytotoxic and hemolytic
analysis of the optimized CQ NFs demonstrated that CS-NFs significantly improved
the biological activities of CQ in protection against hemolysis, and increased cytopathic
effect in Triple Negative Breast Cancer Cells (MDA MB-231). Moreover, qRT-PCR
analysis showed downregulation in the expression of anti-apoptotic protein Beclin-1
was observed in the CQ NF-treated cells. These results imply that optimized CQ NFs
can prove to be an effective treatment against TNBC.
