COL5A1 and central nervous system cancer: We observed significant differences in the incidence of COL5A1 expression between different grades and different pathologic types of gliomas: (i) high-grade gliomas expressed significantly higher levels of COL5A1 compared with low-grade gliomas; (ii) recurrent gliomas expressed a slightly more amount of COL5A1 than the primary; (iii) IDH wild-type gliomas had a higher COL5A1 expression than the IDH mutation type; and (iv) gliomas with 1p/19q co-deletion expressed lower levels of COL5A1 than the 1p/19q non-co-deletion type.