How to add a value for column in Item adding event in Remote event receivers using csom

public SPRemoteEventResult ProcessEvent(SPRemoteEventProperties properties)
{
SPRemoteEventResult result = new SPRemoteEventResult();
if (properties.EventType == SPRemoteEventType.ItemAdding)
{
result.ChangedItemProperties.Add("Title", "After adding");
result.Status = SPRemoteEventServiceStatus.Continue;
}
return result;
}