Citric acid can cause a decrease in the expression of anti-apoptotic molecules, such as BCL-2 and myeloid cell leukaemia 1(Mcl-1) [208,209,210], and an increase in the expression of apoptosis-initiating and executing molecules, such as caspase family-related proteins (caspase-2/3/8/9), which finally inhibit tumour cells [211,212]. Here, BCL2 is linked to neoplasm.