Since they were first described in the 1990s, circulating microRNAs (miRNAs) have provided an active and rapidly evolving area of current research that has the potential to transform cancer diagnostics and therapeutics. In particular, miRNAs could provide potential new biomarkers for prostate cancer, the most common cause of cancer in UK men. Current diagnostic tests for prostate cancer have low specificity and poor sensitivity. Further, although many prostate cancers are so slow growing as not to pose a major risk to health, there is currently no test to distinguish between these and cancers that will become aggressive and life threatening. Circulating miRNAs are highly stable and are both detectable and quantifiable in a range of accessible bio fluids, thus have the potential to be useful diagnostic, prognostic and predictive biomarkers. This review aims to summarise the current understanding of circulating miRNAs in prostate cancer patients and their potential role as biomarkers.

MicroRNAs (miRs) play an important role in the development of many complex human diseases and may have tumour suppressor or oncogenic (oncomir) properties. Prostate cancer is initially an androgen-driven disease, and androgen receptor (AR) remains a key driver of growth even in castration-resistant tumours. However, AR-mediated oncomiR pathways remain to be elucidated. We demonstrate that miR-27a is an androgen-regulated oncomir in prostate cancer, acting via targeting the tumour suppressor and AR corepressor, Prohibitin (PHB). Increasing miR-27a expression results in reduced PHB mRNA and protein levels, and increased expression of AR target genes and prostate cancer cell growth. This involves a novel mechanism for androgen-mediated miR regulation, whereby AR induces a transient increase in miR-23a27a24-2 transcription, but more significantly accelerates processing of the primiR-23a27a24-2 cluster. Androgens therefore regulate miR-27a expression both transcriptionally (via AR binding to the cluster promoter) and post-transcriptionally (accelerating primiR processing to the mature form). We further show that a miR-27a anti-sense oligonucleotide, by opposing the effects of mir-27a, has therapeutic potential in prostate cancer.

Background:Post-molar pregnancy gestational trophoblastic tumours (GTT) have been curable with chemotherapy treatment for over 50 years. Because of the rarity of the diagnosis, detailed structured information on prognosis, treatment escalations and outcome is limited.Methods:We have reviewed the demographics, prognostic variables, treatment course and clinical outcomes for the post-mole GTT patients treated at Charing Cross Hospital between 2000 and 2009.Results:Of the 618 women studied, 547 had a diagnosis of complete mole, 13 complete mole with a twin conception and 58 partial moles. At the commencement of treatment, 94% of patients were in the FIGO low-risk group (score 0–6). For patients treated with single-agent methotrexate, the primary cure rate ranged from 75% for a FIGO score of 0–1 through to 31% for those with a FIGO score of 6.Conclusion:In the setting of a formal follow-up programme, the expected cure rate for GTT after a molar pregnancy should be 100%. Prompt treatment and diagnosis should limit the exposure of most patients to combination chemotherapy. Because of the post-treatment relapse rate of 3% post-chemotherapy, hCG monitoring should be performed routinely.

No abstract