Table 1.

Summary of aberrant actin isoform expression in various cancers.

Actin Isoform	Cancer(s) in which it is aberrantly expressed	Upregulated or Downregulated	mRNA or Protein	Tumour cells or tumour tissue analysed	Clinical Outcome	Reference
ACTA1	Head and neck squamous cell carcinomas	Downregulated	mRNA and protein	Cells and tissue	Correlated with greater aggressiveness and shorter survival	[24], [25]
	Colorectal cancer	Downregulated	mRNA	Tissue	–	[26]
	Prostate	Downregulated in the cancer, Upregulated in associated cancer-associated fibroblasts	mRNA	Cells and tissue	–	[29], [31]
	Pancreatic adenocarcinoma	Downregulated	mRNA	Cells and tissue	–	[28]
	Oral squamous cell carcinoma	Upregulated	mRNA	Tissue	Shorter survival	[32]
	Basal-like breast cancer	Upregulated	mRNA	Tissue	Associated with drug resistance	[33]
ACTA2	Lung adenocarcinoma	Upregulated	mRNA and protein	Cells and tissue	Shorter survival and early distant metastasis	[44]
	HER2+ breast cancer	Upregulated	mRNA and protein	Cells and tissue	Shorter survival	[43]
	Colorectal cancer	Upregulated in the cancer, Upregulated in associated cancer-associated fibroblasts	mRNA and protein	Cells and tissue	Shorter disease-free survival	[45], [49]
	Bladder cancer	Upregulated	mRNA	Tissue	Shorter survival	[42]
	Non-small cell lung cancer	Upregulated	Protein	Cells	–	[46]
	Head and neck cancers	Upregulated in associated cancer-associated fibroblasts	mRNA and protein	Cells and tissue	Shorter survival	[47]
	Pancreatic cancer	Upregulated in associated cancer-associated fibroblasts	mRNA and protein	Cells and tissue	–	[48]
ACTB	Sarcoma	Upregulated	Protein	Cells	–	[56]
	Colon adenocarcinoma	Upregulated	Protein	Cells	–	[53]
	Hepatoma	Upregulated	Protein	Cells	Greater metastatic potential	[54]
	Melanoma	Upregulated	mRNA	Cells	–	[58]
	Gastric cancer	Upregulated	mRNA	Tissue	–	[62]
	oesophageal carcinoma	Upregulated	Protein	Tissue	–	[59]
	Non-small cell lung cancer	Upregulated	mRNA	Cells and tissue	–	[61], [63]
	Breast cancer	Upregulated	mRNA	Cells	–	[60]
	Lymphoma	Upregulated	Protein	Cells	–	[66]
	Cervical cancer	Downregulated	Protein	Cells		[65]
ACTC1	Head and neck cancer	Upregulated	Protein	Cells	Greater distant metastasis	[76]
	Bladder cancer	Upregulated	mRNA	Tissue	–	[79]
	Urothelial cancer	Upregulated	mRNA	Tissue	–	[79]
	Prostate cancer	Upregulated	mRNA	Tissue	Predictor of the diseased/cancer state	[78]
	Non-small cell lung cancer	Upregulated	mRNA	Cells	–	[80]
	Breast cancer	Upregulated	mRNA	Cells	Multi-drug resistance	[81], [82]
	Glioblastoma	Upregulated	mRNA	Cells	Greater distant metastasis	[77], [83]
ACTG1	Skin cancer	Upregulated	mRNA	Tissue	–	[85]
	Hepatocellular carcinoma	Upregulated	Protein	Cells and tissue	Shorter survival and high expression is correlated to advanced tumour stage	[87]
	Non-clear cell renal cell carcinoma	Upregulated	mRNA	Tissue	–	[88]
	Colorectal cancer	Upregulated	Protein	Cells	Greater distant metastasis	[90]
	Lung cancer	Upregulated	mRNA	Cells	–	[89]
	Cervical cancer	Upregulated	mRNA	Tissue	Can serve as a biomarker for malignancy.	[91]
	Acute lymphoblastic leukaemia	Downregulated	Protein	Cells	Resistance to microtubule-targeting agents	[93]
	Neuroblastoma	Downregulated	Protein	Cells	Greater distant metastasis	[86]
	Breast cancer	Downregulated	Protein	Cells	Drug resistance to anti-mitotic agents	[94]
	Lung cancer	Upregulated	Protein	Tissue	–	[92]
	Colon cancer	Upregulated	Protein	Tissue	–	[92]
	Prostate cancer	Upregulated	Protein	Cells	–	[92]
	Pancreatic cancer	Upregulated	Protein	Cells	–	[92]
	Testicular cancer	Upregulated	Protein	Cells	–	[92]
	Colorectal cancer	Upregulated	Protein	Cells	–	[92]
	Oral squamous cell carcinoma	Upregulated	Protein	Cells	–	[92]
ACTG2	Hepatocellular carcinoma	Upregulated	mRNA and protein	Cells and tissue	Correlated with EMT and aggressiveness	[96], [97]