Let me preface by saying that I don't want to overstate what I think is really a rather modest difference of interpretation that you and I have.
I have read the paper, and much of their basic biology seems sound. They show convincingly that pancreatic ductal cancer cell proliferation does not differ between glucose and fructose at a variety of concentrations (figure 1).
They then compare pancreatic tumor to hepatic tumor to normal-ish tissues and show a series of metabolic differences when grown in glucose-containing vs fructose-containing media (figure 2). These changes include transketolase activity, ribose synthesis, and release of C13-labeled lactate into the media. Here, I have a bit of an issue. Nobody is claiming that our high-fructose diet causes us to have a glucose-free plasma, so it's totally non-physiologic to compare just glucose vs just fructose (which some of the panels appear to be doing in this figure, while others are comparing glucose vs fructose+glucose, which is a stronger comparison IMHO).
There are other figures; they are fine. I like their data. Where they lose me is with the claims that they make from their data. They show in figure 1 that there is no proliferative difference in Panc-1 cells between a glucose vs a fructose "diet" at all concentrations, but then based on data in figure 4 they claim that the TK-inhibitor oxythiamine reduces "fructose-induced Panc-1 cell proliferation." Well, which is it: does fructose induce Panc-1 cell proliferation, or does it not? Your answer will depend upon whether you like figure 1 better or figure 4. While these claims appear to be contradictory to me, it's also possible that I didn't read the paper carefully enough so please correct me if I missed something.
At any rate, just because this paper cited other work showing human studies (which it did), that certainly does not mean that this paper itself has policy implications. The human studies that it cited might have policy implications.
Especially given figure 1, which shows no difference in proliferation between cancer cells given fructose and those given glucose, I would have a hard time justifying policy claims with this paper.
I have read the paper, and much of their basic biology seems sound. They show convincingly that pancreatic ductal cancer cell proliferation does not differ between glucose and fructose at a variety of concentrations (figure 1).
They then compare pancreatic tumor to hepatic tumor to normal-ish tissues and show a series of metabolic differences when grown in glucose-containing vs fructose-containing media (figure 2). These changes include transketolase activity, ribose synthesis, and release of C13-labeled lactate into the media. Here, I have a bit of an issue. Nobody is claiming that our high-fructose diet causes us to have a glucose-free plasma, so it's totally non-physiologic to compare just glucose vs just fructose (which some of the panels appear to be doing in this figure, while others are comparing glucose vs fructose+glucose, which is a stronger comparison IMHO).
There are other figures; they are fine. I like their data. Where they lose me is with the claims that they make from their data. They show in figure 1 that there is no proliferative difference in Panc-1 cells between a glucose vs a fructose "diet" at all concentrations, but then based on data in figure 4 they claim that the TK-inhibitor oxythiamine reduces "fructose-induced Panc-1 cell proliferation." Well, which is it: does fructose induce Panc-1 cell proliferation, or does it not? Your answer will depend upon whether you like figure 1 better or figure 4. While these claims appear to be contradictory to me, it's also possible that I didn't read the paper carefully enough so please correct me if I missed something.
At any rate, just because this paper cited other work showing human studies (which it did), that certainly does not mean that this paper itself has policy implications. The human studies that it cited might have policy implications.
Especially given figure 1, which shows no difference in proliferation between cancer cells given fructose and those given glucose, I would have a hard time justifying policy claims with this paper.