(A) In cells expressing a low level of FAVL (VL), there is perhaps a dynamic balance between 2 versions of FANCL protein (L): the free form and the complex form, activating the FA-BRCA tumor suppressor pathway and maintaining chromosomal stability. (B and C) In cells overexpressing FAVL, this balance may be disturbed, as a result of FAVL sequestration of FANCL protein and its enhancement of FANCL turnover. (B) The production of the FA complex E3 will be slightly (or not) affected when levels of FAVL are high but not beyond a threshold level. (C) However, the production of the FA complex E3 will be affected substantially when levels of FAVL exceed the threshold level. Both slightly and substantially compromised complex E3 will be able to restrain the activation of the FA-BRCA tumor suppressor pathway and, ultimately, contribute to chromosomal instability and cancer development within a relatively longer or shorter period of time, respectively.