He added, "It certainly doesn't help when the president of the United States attacks a senator or if a senator bogs down in DNA results".
Trump has often mocked Warren for saying she was Native American because she didn't have documentation of status.
On top of this, there is also a 1999 Affirmative Action Plan Book published by Harvard that appears to identify Warren as Native American.
Surprisingly, conservative panelist Abby Hunstman agreed with Hostin, saying, "I don't know why any politician today thinks that they can out bully Trump, because thus far no politician has been successful".
Sen. Elizabeth Warren's supporters say her the political video she released this week along with the results of a DNA test suggesting she has Native American ancestry show she is capable and willing to confront the president's personal insults - calling her "Pocahontas" for years in reference to controversy over her heritage.
As the Boston Globe reported in 2012, she "listed herself in the Association of American Law Schools directory as a minority, beginning in 1986".
During the 2016 presidential campaign, Trump vowed to contribute $1 million to Warren's favorite charity if a DNA test proved her assertions.
In the interview, the Cambridge Democrat, who has said she will "take a hard look" at running for president after November 6, placed the DNA results within the context of other recent moves she's made to open her background to outside scrutiny.
Trump also claimed that Warren would not have been hired as a Harvard law professor if not for claiming to be a "person of color".
Trump called on his potential 2020 Democratic challenger to apologize and claimed that even the Cherokee Nation "denies her".
Should she keep to this aspiration, she would run in the American primaries for the Democrats. "That will not be something I'll enjoy doing, either".
Again, it's not Trump she'll have to battle.
Secondly, and with all the evidence proving the exact opposite, Warren still stands by her claim that her parents were forced to elope due to family strife over her mother being Indian. But when pressed about her call for him to pay up, he turned defensive.
Ms Warren has claimed Cherokee and Delaware Indian heritage, citing family stories, but until Monday had not presented documentation.
Warren tweeted that Trump is a "cowardly elitist" and that she "won't sit quietly for Trump's racism" so she took the test. "It may soothe his ego - but it won't work", Warren tweeted.
Many Oklahomans take pride in their Indian blood even if, as in Warren's case, they can not trace an ancestor to the original tribal rolls. "What are YOU hiding, @realDonaldTrump?" she wrote.
Trump has bucked decades of precedent by refusing to release the returns.