. 2022 Feb 21;41:71. doi: 10.1186/s13046-021-02237-6

Table 1.

Correlation between circCUL2 expression level and clinicopathologic characteristics of PDAC patients

Characteristics	N of cases	circCUL2 expression level
		Low	High	p value ^a
Total cases	161	81	80
Gender				0.529
Male	87	46	41
Female	74	35	39
Age, mean ± SD, year^b		60.10 ± 9.29	58.46 ± 7.96	0.232
Differentiation				0.061
Well	11	7	4
Moderate	88	50	38
Poor	62	24	38
TNM stage (AJCC) ^c				<0.001^***
I	31	25	6
II	103	50	53
III	27	6	21
Lymph-node metastasis				<0.001^***
Negative	61	48	13
Positive	100	33	67
Perineural invasion				0.641
Negative	21	12	9
Positive	140	69	71
Long-term smoking^d				0.093
No	141	67	74
Yes	20	14	6
High-fat diet				0.269
No	138	72	66
Yes	23	9	14
Chronic pancreatitis				0.831
No	135	67	68
Yes	26	14	12
Abbreviations: SD = standard deviation; TNM = tumor node metastasis; AJCC = American Joint Committee on Cancer. ^a Chi-square test (except for age), ^* p < 0.05, ^ p < 0.01, ^* p < 0.001. ^b Unpair t test, ^* p < 0.05, ^ p < 0.01, ^* p < 0.001. ^c Patients were staged in accordance with the 8th Edition of the AJCC Cancer’s’ TNM Classification. ^d Long-term smoking (duration ≥ 29 years).