Review Article
Peptide Receptor Targeting in Cancer: The Somatostatin Paradigm
Table 2
Main signalling systems regulated by the activation of SST receptors.
| | sst1 | sst2 | sst3 | sst4 | sst5 |
| cAMP production | | | | | | Adenylyl cyclase | ▼ | ▼ | ▼ | ▼ | ▼ | Tyrosine phosphatases | | | | | | PTP | ▲ | ▲ | ▲ | ▲ | ▲ | SHP-1 | ∘ | ▲ | ▲ | ∘ | ▲ | SHP-2 | ▲ | ▲ | ▲ | ▲ | ▲ | Ion channels and transporters | | | | | | Ca2+ channels | ▼ | ▼ | ∘ | ∘ | ▼ | K+ currents | ▲ | ▲ | ▲ | ▲ | ▲ | Na+/H+ exchanger 1 (NHE1) | ▼ | ▼/▲ | ∘ | ▲ | ∘ | MAPK | | | | | | ERK1/2 | ▼/▲ | ▼/▲ | ▼ | ▲ | ▼ | p38 | ∘ | ▲ | ∘ | ▲ | ∘ | JNK | ∘ | ▼ | ∘ | ∘ | ▲ | Tyrosine kinases | | | | | | c-Src | ▲ | ▲ | ∘ | ∘ | ∘ | JAK2 | ▲ | ▲ | ∘ | ∘ | ∘ | Phospholipid kinases | | | | | | PI3K | ▼/▲ | ▼/▲ | ∘ | ∘ | ∘ | Cyclin-dependent kinase inhibitors | | | | | | p27kip1 | ▲ | ▲ | ∘ | ∘ | ∘ | p21Cip1 | ▲ | ∘ | ∘ | ∘ | ∘ | Zac1 | ∘ | ▲ | ∘ | ∘ | ∘ | Nitric oxide synthases | | | | | | nNOS | ∘ | ▲/▼ | ▼ | ∘ | ▼ | eNOS | ▼ | ▼ | ▼ | ∘ | ∘ | Apoptotic pathways | | | | | | p53 | ∘ | ∘ | ▲ | ∘ | ∘ | BAX | ∘ | ∘ | ▲ | ∘ | ∘ | Bcl-2 | ∘ | ∘ | ▼ | ∘ | ∘ |
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▲: activation, ▼: inhibition, ∘: no effects.
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