Kane hit 7 of 14 from the field and made 3 of 6 from 3-point range, while Tinnon had 11 points and 12 boards for the Thundering Herd (9-9, 2-1). Elijah Pittman added 19 points and D.D. Scarver 11, while Nigel Spikes grabbed 11 rebounds.
Marshall improved to 8-1 this year in the Cam Henderson Center.
Robert Sampson collected his fifth double-double of the year with 10 points and 17 rebounds for East Carolina (11-6, 2-2), which had its two-game winning streak snapped.
Miguel Paul added 17 points and five assists, but committed seven of the Pirates' 18 turnovers.
Marshall scored 24 points off the giveaways, and also outscored East Carolina 52-30 in the paint and 20-4 on fast breaks.
Northwestern has never made the NCAA tournament, but the Wildcats' upward trajectory suggests 2016-17 could finally be the season it happens.
Dillon Brooks, who led Oregon with 16.7 points per game last season, will opt out of the NBA draft process and return to the Ducks, a source told ESPN.
Mississippi State freshman guard Malik Newman will withdraw from the NBA draft, but sources told ESPN he might explore other opportunities besides returning to Mississippi State.