Add this code once the file is uploaded.

uploadFile.CheckOut();

ListItem item = uploadFile.ListItemAllFields;
item["FieldName"] = "SomeFieldValue";
item.Update();

// use OverwriteCheckIn type to make sure not to create multiple versions 
uploadFile.CheckIn(string.Empty, CheckinType.OverwriteCheckIn);

Source: http://stackoverflow.com/questions/9847935/upload-a-document-to-a-sharepoint-list-from-client-side-object-model

Add this code once the file is uploaded.

uploadFile.CheckOut();

ListItem item = uploadFile.ListItemAllFields;
item["FieldName"] = "SomeFieldValue";
item.Update();

// use OverwriteCheckIn type to make sure not to create multiple versions 
uploadFile.CheckIn(string.Empty, CheckinType.OverwriteCheckIn);

Source: https://stackoverflow.com/questions/9847935/upload-a-document-to-a-sharepoint-list-from-client-side-object-model