Cancer is a major public health problem and the second leading cause of mortality around the world. Cancer therapy has been growing in an unprecedented fashion in the past two decades. Specific gene mutation, protein dysfunction, dysregulation of intracellular signaling pathways, and immune response had been targeted. It has been shown that the dysregulation of intracellular signaling pathways mediated by Ca2+a and cAMP participates in the cancer initiation, tumor formation, tumor progression, metastasis, invasion and angiogenesis. Thereby, proteins involved in these pathways, such as Ca2+a channels and cAMP-dependent protein kinase (PKA), represent potential drugs targets for cancer therapy. We recently discovered that the interaction between intracellular signaling pathways mediated by Ca2+a and cAMP (Ca2+a/cAMP signaling interaction) participates in the regulation of several cellular responses, including neurotransmitter/hormone secretion and neuroprotection. Due to importance of the Ca2+a/cAMP signaling in the regulation of cellular proliferation, we have proposed that the pharmacological modulation of these signaling pathways could be a new strategy for cancer therapy.