Many thanks @akulkarni It worked!!
curl -i --header "Accept:application/json" -H "Content-Type: application/json" -u admin:admin -X POST http://nodo1.dominio.es:6080/service/public/v2/api/policy -d '{"name":"lending_2","service":"PoC_Cognosfera_kafka","isEnabled":"true","isAuditEnabled":"true","policyType":"0","policyItems":[{"users":["test"],"accesses":[{"isAllowed":"true","type":"publish"}]}],"resources":{"topic":{"values":["prueba"]}}}'
HTTP/1.1 200 OK
Server: Apache-Coyote/1.1
Set-Cookie: RANGERADMINSESSIONID=8DA224285F1E8FE1E5EF3E7ABA956284; Path=/; HttpOnly
WWW-Authenticate: Negotiate
Set-Cookie: hadoop.auth=; Path=/; Domain=hadoopmaster2.kst.internal; Expires=Thu, 01-Jan-1970 00:00:00 GMT; HttpOnly
X-Frame-Options: DENY
Content-Type: application/json
Transfer-Encoding: chunked
Date: Mon, 29 May 2017 09:02:35 GMT