Summary of in vitro and in vivo studies testing the effects of pure and surface-modified Ag NPs^a.

Surface mod.	Size (in nm)	Main finding	VT	VV	Model systems	Dose/concentration	Cellular/tumoral effects	CCS	Mechanism	Ref.
Pure	8–22C	Ag NPs synthesized from plant extracts induce anticancer activity in lung cancer models	●	●	H1299	VT: 2–30 μg mL−1; VV: 10 μg g−1	Dose-dependent ↓ cell viability. ↓ tumor size & growth		Morphological alterations, ↓ NF-κB transcriptional activity and Bcl2, ↑ caspase-3 and survivin	152
Pure	5–35C	Bio-synthesized Ag NPs exhibit anticancer, antioxidant and anti-angiogenic activity with no adverse effect on liver and kidney		●	DAL	VT: 0–100 μg mL; VV: 50 μg mL−1	Dose-dependent ↓ cell viability ex vivo			187
Pure	9.4–25.9C	Ag NPs synthesized from Nostoc linckia extracts exert anticancer activity in breast cancer models	●	●	VT: MCF-7, WI38, WISH; VV: EAC	VT: 1.56–100 μg mL−1; VV: 5 mg kg−1	Dose-dependent ↓ cell viability. ↓ cell volume, cell count and weight of tumors	●		153
Pure	31.8C	Ag NPs synthesized from Acorus calamus show antitumor activity with complete NP elimination 89 days post-treatment	●	●	VT: Hep2, COLO 205, SH-SY5Y	0–200 μg mL−1	↓ cell viability		↑ ROS, ↓ MMP, ↑ caspases-8, 9 and 3, ↑ lamin and PARP, ↑ MDA, ↓ SOD, GPx and CAT	154
Pure	8–20C	Ag NPs synthesized from Agaricus bisporus cause apoptosis and anti-angiogenesis in combination with gamma radiation	●	●	VT: MCF-7; VV: EAC	VV: 0.1–10 μg kg−1	Dose-dependent ↓ cell viability		↑ caspase-3, ↑ nitric oxide and MDA, ↑ ROS, DNA damage	155
Pure	2.6C, 18C	Ag NPs induce size-dependent cell death in chemo-resistant pancreatic CCs via apoptosis, autophagy, necroptosis and mitotic catastrophe	●		PANC-1, hTERT-HPNE	0–5μg mL−1 (2.6 nm), 0–100 μg mL−1 (18 nm)	Dose-dependent ↓ cell viability. ↓ toxicity with ↑ NP size	●	Apoptosis: ↑ bax, p53, ↓ bcl-2. Necroptosis: ↑ MLKL, RIP1, RIP3. Autophagy: ↑ LC3-II	91
Citrate-coated	5C	Ag NPs initiate antitumor effects and trigger the activation of a tumor cell-specific immune response	●	●	VT: HeLa, A549, KLN205; VV: KLN205, CT26	VT: 5–50 μg mL−1; VV: 100 μg	Dose-dependent ↓ cell viability. Tumor inflammation and ↓ tumor size		↑ ROS, mitochondrial damage, autophagy, immunomodulatory effects (↑ NFκB pathway and ↑ IL-1α)	175
PVP-coated	30–50	Ag NPs induce toxicity to CCs via necrosis and increase survival of mice	●	●	L5178Y-R	VT: 9–579 nM; VV: 20 mg kg−1	Dose-dependent ↓ cell viability			97
PVP-coated	5–75C	Ag NPs show selective cytotoxicity against TNBC cells regardless of size, shape or coating	●	●	VT: TNBC, MDA-MB-231, SUM159; VV: TNBC	VT: 0–60 μg mL−1; VV: 6 mg kg−1	↓ proliferation. ↓ tumor growth rate, ↑ survival rate	●	Impairment of cellular redox balance, ↑ ER stress, UPR activation, ↑ CHOP, DNA damage	178
EPS-coated	11C	Ag NPs biogenerated by Klebsiella oxytoca DSM 29614 show anticancer activity mainly by induction of autophagy	●		SKBR3	5 and 50 μg mL−1	Dose- and time-dependent ↓ colony-forming ability		↑ ROS. Autophagy: ↑ ATG5, ATG7, LC3-II and Beclin-1, ↓ AKT, p-AKT, p62 and HSP90	177
Ag+-R, Ag0-R	<2C	Compared to Ag+-R NCs, Ag0-R nanoclusters (NCs) exhibit greater release of Ag species	●		BJ	62.5, 250 and 1000 mM	Toxicity by Ag0-R NCs > Ag+-R NCs		Activation of p53	176
TAT-coated	8C	Antitumor activity in both multidrug resistant and non-resistant CCs is greater with TAT functionalization	●	●	VT: HeLa, MCF-7(/ADR), B16; VV: B16	VV: 1 nmol kg−1	↓ cell viability. ↓ tumor growth at lower doses than DOX			191

^{a C}core size, ^HDhydrodynamic size, VT in vitro, VV in vivo, CCS cancer-cell specific.