Table 1.

The relationship between HHLA2 expression in tumour tissue and cancer patient prognosis.

Human cancer type	cancer cases	Results: Expression in tumour cells and relationship with prognosis	Analysis method	antibody	Refs
Prostate cancer	239	HHLA2 higher expression was related to worse prognosis because of higher tumour grade, tumour stage, and lymphatic metastasis.	IHC	clone 566.1	[64]
Hepatocellular carcinoma (HCC)	462	HHLA2 expression was higher, and the high level of HHLA2 was related to a worse prognosis.	qRT-PCR IHC IHC	– Cell Signaling Technology, Danvers, MA, USA ab214327, Abcam, Cambridge, UK	[65], [67], [66]
Oral squamous cells carcinoma (OSCC)	201	Increased HHLA2 expression in oral squamous cells carcinoma and higher HHLA2 expression levels indicate poor prognosis.	IHC	Abcam, Cambridge, UK	[59]
	241	Approximately 23.1 % of patients showed B7 high expression, and HHLA2 expression at a high level was related to good clinical outcomes.	–	–	[28]
Pancreatic cancer	365	Higher HHLA2 expression was related to a better prognosis, such as prolonged OS, delayed cancer recurrence, improved post-operative cancer-specific survival, and less immune evasion.	IHC and RT-qPCR IHC IHC IHC	AP10650a, Abgent, San Diego, CA, USA B7H5 mAb HPA055478, Sigma-Aldrich clone 566.1	[12], [7], [68], [69]
Osteosarcoma tumours	62	HHLA2 was expressed in a large proportion of osteosarcoma tumours, and its expression was related to poorer survival.	IHC	clone 566.1	[62]
Lung cancer	1344	High HHLA2 expression was related to metastasis higher stage and poor progression-free survival in lung cancer.	IHC IHC IHC	ab214327, Abcam, Cambridge, UK clone 566.1 A13262, IgG, Abclonal, Inc	[36], [37], [38]
Ovarian cancer	64	HHLA2 overexpression was related to inhibiting the proliferation of ovarian cancer cells.	IHC and qRT–PCR	clone 566.1	[60]
Gastric cancer	633	HHLA2 was overexpressed in gastric cancer tissue, and the high level of HHLA2 was associated with deep tumour invasion, advanced clinical stage, metastasis, and short OS.	IHC and qRT–PCR IHC	Abcam, Cambridge, UK B7H5 mAb	[70], [58]
Glioma	669	High expression of HHLA2 was associated with a better prognosis for patients with glioma.	IHC	cat. no. HPA055478, Sigma-Aldrich, Merck KGaA	[71]
Intrahepatic cholangiocarcinoma (ICC)	153	High HHLA2 expression level was significantly associated with poor OS.	IHC	Atlas, Stockholm, Sweden	[9]
Ampullary tumour	72	High HHLA2 expression levels were related to delayed cancer recurrence and improved post-operative cancer-specific survival.	IHC and RT-PCR	clone 566.1	[69]
Bladder urothelial carcinoma	212	HHLA2 was overexpressed in tumour tissue, and high HHLA2 expression significantly correlated with poor prognosis.	IHC and qRT-PCR	ab214327, Abcam, Cambridge, UK	[72]
Breast cancer	50	HHLA2 expression was aberrant in tumour tissue. In addition, overexpression of HHLA2 was related to worse consequences	IHC	clone 566.1	[4]
Colorectal carcinoma	63	High HHLA2 expression was related the invasion depth.	IHC	ab214327, Abcam, Cambridge, UK	[73]
Clear cell renal cell carcinoma (ccRCC)	534	High HHLA2 expression was present in tumours, and higher HHLA2 expression indicates better prognosis of the patient with kidney clear cell carcinoma.	IHC	clone 566.1	[74]
	585	High HHLA2 mRNA expression level was present in tumour tissues, and higher expression of HHLA2 was related to poorer OS, larger tumour size, and advanced TNM stage.	IHC IHC and RT-PCR IHC and qRT-PCR	Sigma- Aldrich, HPA055478 LSC321945, Lifespan Biosciences Dako Corporation, USA	[75], [76], [77]
Cervical adenocarcinoma	76	HHLA2 expression was negatively related to lymph node metastasis, and high HHLA2 expression was associated with more prolonged disease-free survival.	IHC	Thermo Fisher Scientific, IL	[78]
Oesophageal cancer	185	High HHLA2 expression in oesophageal cancer was related to worse OS.	–	–	[29]

IHC immunohistochemistry.

qRT-PCR quantitative reverse transcription-polymerase chain reactio.