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Among the PTPs superfamily, PTP1B has become prom-inent for its down regulation of both insulin and leptin signaling and control of glucose homeostasis and energy expenditure (Tsou and Bence 2012). It terminates the sig-naling cascade by dephosphorylating the tyrosine residues on its substrates, the phosphotyrosine kinases (PTKs). As a major negative regulator of Janus kinase in JAK-STAT signaling, moreover, PTP1B is recognized to be a key link between metabolic diseases (Tonks 2003), inflammation (Pike et al. 2014) and cancer (Feldhammer et al. 2013). In insulin signaling, PTP1B acts to dephosphorylate the insulin receptor (IR) at tandem Y1162/Y1163 (Tsou and Bence 2012; Galic et al. 2005) and possibly the insulin re-ceptor substrate 1 (IRS-1) (Galic et al. 2005). Increasing expressed PTP1B and its activity result in over dephos-phorylation of IR and kinases leading to interruption of insulin cascades and hence insulin resistance in target tissues