**3. Novel treatment strategy of antipsychotics**

If the SCZCGs are responsible for the gene targets of disease mechanism of schizophrenia, the associated complexes or drugs derived from SCZCGs may contribute to novel treatment for schizophrenia whether they were traditional or atypical antipsychotics related. From the analysis of important cliques in SCZCGs, some of the drugs derived from clique analysis and mapped to the gene targets from DrugBank such as lovastatin and retinoid acid.

Lovastatin, a cholesterol-lowering agent is targeted by HDAC2. It was also the principal statin produced from *Monascus purpureus* derived from red yeast rice [79]. It has been implicated that statins target many of the pathways to neuroprogression in schizophrenia [80]. Adapalene, Tazarotene, and Tamibarotene are retinoids which involved RARA gene with multiple functions including eye vision, immune function, and activation of tumor suppressor genes. Retinoic acid has been reported for the treatment of schizophrenia. More and more evidence regarding retinoid dysregulation in schizophrenia implicated targeting retinoid receptors may be a novel approach to treat schizophrenia [25, 81].

Although there is not yet a clear and well-evidenced disease mechanism for schizophrenia, the current findings may contribute to novel indications or drug repurposing for schizophrenia. However, further evaluation and validation are needed in the near future.
