XBP1 and Miyoshi myopathy: Univariate Cox proportional hazards regression analysis was conducted to determine the prognostic value of the quantified mRNA expression; the results indicated that in MM patients, higher expression of CXCR4, MARCKS, POMP, PSMB5, TXN, and XBP1 was significantly correlated with shorter PFS (Table 4, Figure 3).