U373, A172, and U87 GBM cell lines, expressing high levels of OASIS, have been tested for their response to ER stress upon OASIS knockdown, and not only was the expression of BiP and GRP94 chaperones reduced, but chondroitin sulfate PGs (CSPGs) levels were also diminished. The gene discussed is HSP90B1; the disease is glioblastoma.