What are the causes of anti-social behavior?
There are numerous barriers such as racial, cultural and parental influences.
Parents that are overprotective can feed false ideas into youth prompting lack of interaction with people of their age. Staunch Religious beliefs that prohibit association with others of disimilar faith can cause isolation. The same applies with racial segregation. These factors can cause lack of self esteem and have a negative effect on career growth and development.
Insecurity is the primary cause. This is fundamental, as outlined in Maslow's needs hierarchy.
A previous answer detailed some mechanisms, but not really the root causes. Why a person develops or retains insecurities is the whole range of primarily environmental factors. But, all anti-social behavior is really an individual's attempt to establish a personal sense of security.
Whether by withdrawal or lashing out, the behavior is a response to the individual's fear, and is a defensive posture. Establishing a sense of security for an individual at whatever level(s) are affected is therefore necessary to effect any positive change in the behavior.