Table 4.

Model parameter estimates. Notes. #1: Cell death rate equals the birth rate in a normal pancreas. #2: For carcinogenesis the death rate of pancreatic cancer cells must be less than their death rate. As a point of departure we assume the death rate for cancerous cells is 0.75 the replication rate. #3: Using an assumed mutation rate per base pair per generation of 5 x 10⁻¹⁰, Yachida and Jones et al. (2010) estimated the mutation rate per cell generation to be 0.016. We require the mutation rate per cell per unit time, and hence estimate k′ to be 0.016 mutations / cell-replication * 1 cell-replication / 2.3 cell days. #4 We set the repair rate to be equal to 99 percent of the mutation rate per cell per unit time; k″=0.99 x 0.16/2.3.

Parameter	Description	Units	Estimate	Reference/note
b′	replication of cells in PanIN	Cell divisions per cell per unit time	1 replication / 2.3 cell days	(Yachida et al. 2010)
b″	replication of pancreatic cancer cells	Cell divisions per cell per unit time	1 replications / 2.3 days per cell division	(Yachida et al. 2010)
b5	Replication of metastatic cancer cells	Cell divisions per cell per unit time	1 replication / 56 days	(Yachida et al. 2010)
μ′	Normal cell death	Deaths per cell per unit time	1 death / 2.3 cell days	#1
μ″	Death of pancreatic cancer cells	Deaths per cell per unit time	μ″ < b″ – k54 ~0.75 * 1/2.3 deaths / cell day	#2
k′	Mutation/initiation to reversible pre-cancerous or cancerous condition	Mutations per cell per unit time	k′=6.957*10−3	#3
k″	DNA repair to normal or earlier cancer state	Repair to prior cell state per cell per unit time	k″=6.887*10−3	#4