CXCR4 and B-cell chronic lymphocytic leukemia: If these outliers were omitted, compared to conventional culture, (i) expression of VCAM1 was reduced in CLL cells both in CMC-PEG and collagen scaffolds, (ii) MCL1 expression increased in CLL cells in CMC-PEG but decreased in collagen scaffolds, (iii) CXCR4 was downregulated in collagen-cultured and upregulated in CMC-PEG cultured CLL cells, and (iv) CCL4 expression was higher in CLL cells growing in collagen scaffolds (for significance, see Table 3).