Kobe Bryant scored a Lakers-best 26 points on his return after missing 14 games with a badly sprained right ankle.
The All-Star guard was booed by the crowd at Cleveland's Gund Arena and missed his opening shot. Overall, he showed few signs of rust after being on the sidelines for more than a month.
"It feels great to be back," said Bryant after the Lakers lost for the fifth time in six games.
James produced his best work for Cleveland in the second half with 21 points.
In Miami, Dwyane Wade poured in 28 points and Shaquille O'Neal 27 as the Heat defeated the San Antonio Spurs 96-92 in a showdown between the Eastern and Western conference leaders.
Wade and O'Neal outplayed Tim Duncan and the Spurs back court of Tony Parker and Manu Ginobili to claim their first win over San Antonio in three years.
Ginobili had 24 points for the Spurs while Parker hit for 22 and Duncan 20.
In Minneapolis, Ben Gordon had 21 points as the Chicago Bulls edged the Minnesota Timberwolves 87-83 to ruin Kevin McHale's debut as coach.
Taking over from Flip Saunders after he was fired Saturday, McHale failed to inspire the Timberwolves as they were beaten for the eighth time in nine games.
Latrell Sprewell collected 26 points for Minnesota while NBA MVP Kevin Garnett registered 23 points and 14 rebounds.
In New York, Tim Thomas scored a three-pointer as time expired to lift the Knicks to a 102-99 victory over the expansion Charlotte Bobcats.
Jamal Crawford had 23 points for the Knicks, who won for only the fourth time in 22 outings.
In East Rutherford, Vince Carter notched 23 points and Jason Kidd added 13 points and eight assists to spark the New Jersey Nets to a 94-79 rout of the
The loss spoiled Kenyon Martin's homecoming. Traded to Denver in the off-season, the popular forward received a warm welcome from the New Jersey fans but was held to 13 points.
In Toronto, Chris Bosh recorded 26 points and 10 rebounds and Rafer Alston added 18 points, including 10 in the final quarter, as the Raptors downed the Los Angeles Clippers 109-106 to snap a four-game losing skid.
Elton Brand had 26 points and 11 rebounds for the Clippers, who have lost five straight.
In Boston, Mike Bibby contributed 27 points and Chris Webber posted a triple-double as the Sacramento Kings overcame the Celtics 104-100.
Webber picked up 14 points, 17 rebounds and 12 assists while Brad Miller and Cuttino Mobley each scored 20 points to help the Kings end a four-game losing run.
In Orlando, Steve Francis and Hedo Turkoglu notched 22 points apiece to carry the Magic past the New Orleans Hornets 97-94.
In Indianapolis, Stephen Jackson had 19 points and eight rebounds and Jermaine O'Neal added 11 points and eight boards to lead the Indiana Pacers to a 76-73 win over the Memphis Grizzlies.
In Seattle, Dirk Nowitzki claimed 31 points and 11 rebounds and Michael Finley added 23 points and 11 boards as the Dallas Mavericks beat the SuperSonics 95-92.
Rashard Lewis had 18 points for the SuperSonics, who lost for the first time in six games.
In Oakland, Joe Johnson recorded 23 points while Quentin Richardson and Shawn Marion each chipped in with 21 to guide the Phoenix Suns to a 106-102 overtime victory over the Golden State Warriors.
Steve Nash contributed 20 points and 12 assists for the Suns while Mike Dunleavy registered 24 points for the Warriors.
In Houston, Yao Ming posted 23 points and eight rebounds and Tracy McGrady added 18 points, including four free throws in the final seconds, as the Rockets squeezed past the Portland Trail Blazers 81-80.