Chloroquine dihydrochloride (20 μM) inhibits IL-12p70 release and reduces Th1-priming capacity of activated human monocyte-derived Langerhans-like cells (MoLC). Chloroquine dihydrochloride (20 μM) enhances IL-1–induced IL-23 secretion in MoLC and subsequently increases IL-17A release by primed CD4+ T cells[1]. Chloroquine dihydrochloride (25 μM) suppresses MMP-9 mRNA expression in normoxia and hypoxia in parental MDA-MB-231 cells. Chloroquine dihydrochloride has cell-, dose- and hypoxia-dependent effects on MMP-2, MMP-9 and MMP-13 mRNA expression. TLR7 and TLR9 inhibition using IRS-954 or Chloroquine dihydrochloride significantly reduces HuH7 cell proliferation in vitro.
Chloroquine dihydrochloride (0.01-100 μM; 48?hours) potently blocked virus infection (vero E6 cells infected with SARS-CoV-2) at low-micromolar concentration (EC50=1.13?μM). Chloroquine dihydrochloride blocks virus infection by increasing endosomal pH required for virus/cell fusion, as well as interfering with the glycosylation of cellular receptors of SARS-CoV.

Chloroquine dihydrochloride (80 mg/kg, i.p.) does not prevent the growth of the triple-negative MDA-MB-231 cells with high or low TLR9 expression levels in the orthotopic mouse model.
TLR7 and TLR9 inhibition using IRS-954 or Chloroquine dihydrochloride significantly inhibits tumour growth in the mouse xenograft model. HCC development in the DEN/NMOR rat model is also significantly inhibited by Chloroquine.