Search queries used in Embase for the systematic review. ('cancer cell'/exp OR 'cancer cell' OR 'cancer cell model' OR 'cancer cells' OR 'cancerous cell' OR 'cancerous cells' OR 'cell, cancer' OR 'malignancy cell' OR 'malignancy cells' OR 'malignant cell' OR 'malignant cells' OR 'malignant tumor cell' OR 'malignant tumour cell' OR 'oncocyte' OR 'oncocytes' OR 'cancer cell line'/exp OR 'cancer cell line' OR 'cancer cell lines' OR 'cancer cell strain' OR 'cancer derived cell line' OR 'cancer line' OR 'cancerous cell line' OR 'malignancy cell line' OR 'malignancy-derived cell line' OR 'malignant cell line' OR 'malignant line' OR 'cells'/exp OR 'cell' OR 'cells') AND ('uncaria tomentosa'/exp OR 'uncaria tomentosa' OR 'cat`s claw') AND ('ic50'/exp OR 'cytotoxicity'/exp OR 'cell toxicity' OR 'cytotoxic activity' OR 'cytotoxic effect' OR 'cytotoxic reaction' OR 'cytotoxicity' OR 'apoptosis'/exp OR 'ap-optosis' OR 'apo-ptosis' OR 'apoptosis' OR 'apoptotic cell death' OR 'apoptotic cellular death' OR 'apoptotic death' OR 'apoptotic suicide' OR 'apoptotic-like cell death' OR 'cell suicide' OR 'cellular suicide' OR 'programmed cell death' OR 'programmed cell death type i' OR 'suicidal cell death')