Update field on `customer_entity` table

I created a new field on customer_entity table.

 $  setup->getConnection()->addColumn(             $  setup->getTable('customer_entity'),             'profession',             [                 'type' => \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,                 'comment' => 'Profession',                 'nullable' => false,                 'default' => false,             ]         ); 

Now I need to update this field. I’m trying

    use Magento\Customer\Model\CustomerExtractor as CustomerExtractor;      $  customer = $  this->customerExtractor->extract('customer_account_create', $  this->_request);     $  customer->setCustomAttribute('profession','test'); 

but the field on table stay blank. No error appears.