For example, when patients suffering from early relapsing multiple sclerosis (MS) become infected with helminths the disease stops progressing, and circulating myelin-recognizing Treg appear in the peripheral blood 32, 33, an exciting observation that has led to formal clinical trials 34.
These results raised the possibility that breast imaging techniques using low-dose ionising radiation may induce breast cancers or cause existing breast tumours to progress, if the circulating levels of oestrogen are elevated in women at the time of mammography exposure.
However, recurrent prostate tumors advance to an androgen-independent state in which they progress in the absence of circulating testosterone, leading to metastasis and death.
Although the development of early detection tests had led to an improvement in prognosis for patients with localised PCs treated with prostatectomy, AI lesions may eventually develop and progress despite low levels of circulating androgens (Tannock et al, 2004; Mimeault and Batra, 2006; Freedland, 2010).
Research on circulating miRNAs can only progress by bringing more statistical rigour to bear in this field and by evaluating changes of individual miRNAs in the context of the overall miRNA network.
In this review, we outline recent progress in the field of circulating biomarkers in metastatic prostate cancer and evaluate their potential for enabling this vision of real-time precision medicine.
Therefore, such diagnostic procedures may prove useful for patient selection or for monitoring the progress of treatment with long circulating nanoparticles carrying anti-cancer agents, thus minimizing damage to this important line of body's defence cells, and are discussed.
While the identification of circulating miRNA in breast cancer is progressing rapidly, exploring miRNAs investigated in other (often related) metastatic cancers may inform current work in the breast cancer field.
As prostate cancer progresses from hormone sensitive to hormonerefractory, the circulating concentrations of IL-6 in the serum of patients increase (Fearon et al, 1991; Drachenberg et al, 1999; Heinrich et al, 2003).
Further molecular studies are needed to determine the mechanisms by which high-grade PIN induced by chronic bacterial infection and inflammation progresses towards an invasive carcinoma independently of circulating androgens and AR.
