Table 2.

Different types of MNs, characteristics of MNs, matrixes, the loaded drugs, the diseases treated with MNs, and the treatment methods in cancer therapy

MN types	Characteristics	Matrixes	The loaded drugs	Diseases	Treatment methods	Refs
Solid MNs	High mechanical strength Low biosafety Low biocompatibility	Stainless steel	Dabrafenib, trametinib	Melanoma	PTT	[95]
		Silicon	Cholesterol-modified housekeeping gene (Gapdh) siRNA	Genetic disease	Gene therapy	[68]
		Oscillating MN device dermapen	Imiquimod	BCC	Chemotherapy	[69]
		HA, stainless steel	Itraconazole	BCC	Chemotherapy	[122]
Dissolving MNs	Excellent biocompatibility Excellent biosafety Release the loaded drug rapidly Wide range of applications Simple preparation process	HA	5-Fu; ICG	Human epidermoid cancer, Melanoma	PTT Chemotherapy	[96]
		PVP K30: PVA 103 = 6: 1, PVP K90	CuS NPs, CPT	Melanoma	PTT; Chemotherapy	[94]
		HA	5-ALA	Skin lesions	PTT	[105]
		PVP	Cationic delivery peptide (RALA), DNA	Immunogenic disease	Gene therapy	[109]
		PVA	RALA/pDNA NPs	Cervical Cancer	Gene therapy	[111]
		PVA	CU-NS	Skin cancer	Chemotherapy	[75]
		HA	Cur	Melanoma	Chemotherapy	[87]
		Sodium carboxymethylcellulose (SCMC)	LCC-NPs	Head and neck cancer	Chemotherapy	[117]
		Maltose	Honokiol, Oleic acid	Breast cancer	Chemotherapy	[119]
		PVP	Imiquimod	BCC	Chemotherapy	[120]
		PVP	aPD-1, DDP	Oral squamous cell carcinoma	Chemotherapy; Immunotherapy	[76]
		PVA	RALA/pDNA NPs	CRPC	Immunotherapy	[128]
		CS: NMP = 2 g/80 ml	Polymeric nanocomplex of paclitaxel-encapsulated sulfobutylether-β-cyclodextrin (SBE)/mannosylated N,N,N-trimethylchitosan (mTMC)/DNA	Melanoma	Immunotherapy	[89]
		P127: PEG = 7: 3	Toll-like receptor 7/8 agonist (R848), ovalbumin protein	EG-7 lymphoma	Immunotherapy	[135]
		HA	Ovalbumin protein	EG-7 lymphoma	Immunotherapy	[74]
		HA: PVP K30 = 15%: 40%	GOx	Melanoma	Starvation therapy	[72]
		PVP K30: PVA 103 = 1: 4, PVP K90	GOx, CAT, ICG	Melanoma	Starvation therapy	[147]
		PVP K90	PTX, IR780	Melanoma	PTT Chemotherapy	[73]
		HA	AuNC, DOX	Melanoma	PTT Chemotherapy	[104]
		HA	Chloroquine, CQ, IR780	Melanoma	PTT Immunotherapy	[150]
		PVA: PVP = 2: 1	Lanthanum hexaboride, DOX	Breast Cancer	PTT Chemotherapy	[148]
		HA	p53 DNA, IR820	Human oral epidermoid carcinoma	PTT Gene therapy	[149]
		PVP K90	Poly(cyclopentadithiophene-alt-benzothiadiazole), immune adjuvant polyinosinic–polycytidylic acid	Melanoma	PTT Immunotherapy	[24]
Coated MNs	High transdermal efficiency Prepare the coating solution separately Complex preparation process and mold The coating tends to become uneven	PCL	p53 DNA, PEI	Human oral epidermoid carcinoma	Gene therapy	[82]
		PCL	Dimethylmaleic anhydride-modified polylysine (PLL-DMA), p53 DNA	Human oral epidermoid carcinoma	Gene therapy	[23]
		Stainless steel	BRAF siRNA	Melanoma	Gene therapy	[84]
		Polyethylene glycol (PEG)	Gold nanorod, DOC	Human oral epidermoid carcinoma	PTT Chemotherapy	[99]
Hydrogel MNs	Controlled drug release Excellent biocompatibility Excellent biosafety High risk of drug leakage	GelMA	pDNA, poly(β-aminoester) (PBAE) NPs	Tissue regeneration and cancer therapy	Gene therapy	[81]
		PVA: PEG = 20%: 7.5%	Bevacizumab	Lymphomas Secondary metastatic tumors	Chemotherapy	[79]
		DexMA	DOX, Tra	Melanoma	Chemotherapy	[118]
Biodegradable MNs	Excellent biodegradability Low toxicity	HA	aPD1, GOx	Melanoma	Immunotherapy	[78]
		HA	Cytotoxic T-cell epitope peptide	Melanoma	Immunotherapy	[146]
Core–shell structure MNs	Complex preparation process High drug loading relatively	Oligomeric sodium hyaluronate, PVP: HA = 31.25%: 33%; 40%; 50%	ICG, aPD-L1	Melanoma	PTT Immunotherapy	[85]
		PVP: PVA = 25%: 15%	1-Methyl-tryptophan, ICG, indoleamine 2,3-dioxygenase (IDO)	Melanoma	PTT Immunotherapy	[86]
Injectable MNs	Complex use process	Stainless steel	Cholesterol-modified housekeeping gene (Gapdh) siRNA	Cervical Cancer	Gene therapy	[112]
Derma roller® MNs	High market transformation efficiency	HA	DOX, CEL	Melanoma	Chemotherapy	[115]