In IGF-I receptor-deficient leiomyosarcoma cells autocrine IGF-II induces cell invasion and protection from apoptosis via the insulin receptor isoform A

Efficacy of and resistance to anti-IGF-1R therapies in Ewing's sarcoma is dependent on insulin receptor signaling

“…Ratio of IGF-1R:IR in favor of IR seems to be responsible also for native resistance of some Ewing's sarcoma to anti-IGF-1R therapy and may also explain the lower level of sensitivity of other sarcomas, such as osteosarcoma and rhabdomyosarcoma. In fact, these tumors express higher levels of IR-A than IGF-1R together with IGF-2 (Sciacca et al, 2002;Avnet et al, 2009). Similarly high IR:IGF-1R ratios conveyed resistance to IMC-A12 in breast cancer cells (Ulanet et al, 2010), whereas higher levels of IGF-1R were seen in squamous cell carcinoma of patients responding to figitumumab-containing therapy as compared with non-responders (Gualberto et al, 2010).…”

The insulin receptor is essential for virus-induced tumorigenesis of Kaposi's sarcoma

“…Signaling by the IR promotes survival (Ottensmeyer et al, 2000;Sciacca et al, 2002), which, when inhibited by HNMPA-(AM 3 ), could trigger apoptosis. Accordingly, HNMPA-(AM 3 )-treated cells were assayed for apoptosis using Annexin V-FITC staining.…”

Insulin activates the insulin receptor to downregulate the PTEN tumour suppressor

“…Although numerous studies have shown that insulin may act through IR to affect tumour progression, 42,43 we cannot rule out the possibility that IGF-1 and IGF1-R might downregulate PTEN in a similar fashion as proposed for insulin and IR. Also, IR has been shown to form hetero-receptor complexes with IGF receptor, which could be activated by other insulin-like growth factors as well.…”