"With increasingly tight federal budgets, every dollar invested at the NIH becomes even more precious," the group wrote.
The letter raised specific concerns about communications spending at the National Cancer Institute (NCI), which was criticized in an editorial last month published in the journal Nature.
According to that piece, the NCI spent $45 million on public relations activities in 2012, or enough to fund more than 100 research grants.
The lawmakers asked for a reply from Collins by April 25.
In addition to Upton, the letter came from Marsha BlackburnMarsha BlackburnLatino entrepreneurs need federal protection from pyramid schemes Overnight Tech: GOP split on net neutrality strategy | Trump's phone worries Dems | Bill in the works on self-driving cars Net neutrality fix faces hard sell MORE (R-Tenn.), Energy and Commerce Committee vice chairman; Joe Barton (R-Texas), the panel's chairman emeritus, Joe Pitts (R-Pa.) and Michael BurgessMichael BurgessCongress must not pass Endangered Species reform bill Trump admin moves to 'stabilize' ObamaCare markets Trump touts border crackdown MORE (R-Texas), who lead the panel's health subcommittee; and Jack Kingston (R-Ga.) and Rodney Alexander (R-La.), who lead the Appropriations subcommittee that governs the federal health department.