MicroRNAs associated with metastatic prostate cancer.

OBJECTIVE: Metastasis is the most common cause of death of prostate cancer patients. Identification of specific metastasis biomarkers and novel therapeutic targets is considered essential for improved prognosis and management of the disease. MicroRNAs (miRNAs) form a class of non-coding small RNA molecules considered to be key regulators of gene expression. Their dysregulation has been shown to play a role in cancer onset, progression and metastasis, and miRNAs represent a promising new class of cancer biomarkers. The objective of this study was to identify down- and up-regulated miRNAs in prostate cancer that could provide potential biomarkers and/or therapeutic targets for prostate cancer metastasis. METHODS: Next generation sequencing technology was applied to identify differentially expressed miRNAs in a transplantable metastatic versus a non-metastatic prostate cancer xenograft line, both derived from one patient's primary cancer. The xenografts were developed via subrenal capsule grafting of cancer tissue into NOD/SCID mice, a methodology that tends to preserve properties of the original cancers (e.g., tumor heterogeneity, genetic profiles). RESULTS: Differentially expressed known miRNAs, isomiRs and 36 novel miRNAs were identified. A number of these miRNAs (21/104) have previously been reported to show similar down- or up-regulation in prostate cancers relative to normal prostate tissue, and some of them (e.g., miR-16, miR-34a, miR-126*, miR-145, miR-205) have been linked to prostate cancer metastasis, supporting the validity of the analytical approach. CONCLUSIONS: The use of metastatic and non-metastatic prostate cancer subrenal capsule xenografts derived from one patient's cancer makes it likely that the differentially expressed miRNAs identified in this study include potential biomarkers and/or therapeutic targets for human prostate cancer metastasis.

Percutaneous embolization of transhepatic tracks for biliary intervention.

Significant pain can occur after removing transhepatic catheters from biliary access tracks, after percutaneous biliary drainage (PBD) or stenting. We undertook a randomized prospective study to ascertain whether track embolization decreases the amount of pain or analgesic requirement after PBD. Fifty consecutive patients (M:F, 22:28; age range: 29-85 years; mean age: 66.3 years) undergoing PBD were randomized to receive track embolization or no track embolization after removal of biliary drainage catheters. A combination of Lipoidol and n-butyl cyanoacrylate were used to embolize transhepatic tracks using an 8F dilator. The patients who did not have track embolization performed had biliary drainage catheters removed over a guide wire. A visual analog scoring (VAS) system was used to grade pain associated with catheter removal, 24 h afterward. A required analgesic score (RAS) was devised to tabulate the analgesia required. No analgesia had a score of 0, oral or rectal nonopiate analgesics had a score of 1, oral opiates had a score of 2, and parenteral opiates had a score of 3. The average VAS and RAS for both groups were calculated and compared. Seven patients were excluded for various reasons, leaving 43 patients in the study group. Twenty-one patients comprised the embolization group and 22 patients comprised the nonembolization group. The mean biliary catheter dwell time was not significantly different (p > 0.05) between the embolization group and nonembolization (mean: 5.4 days vs 6.9 days, respectively). In the nonembolization group, the mean VAS was 3.4. Eight patients required parenteral opiates, three patients required oral opiates, and five patients required oral or rectal analgesics, yielding a mean RAS of 1.6. In the embolization group, the mean VAS was 0.9. No patient required parenteral opiates, six patients required oral opiates, and two patients had oral analgesia. The average RAS was 0.6. Both the VAS and the RAS were significantly lower in the embolization group compared with the nonembolization group (p < 0.0023 and p < 0.002, respectively). No complications were seen related to track embolization. Percutaneous track embolization after removal of biliary drainage catheters decreases patient's perception of pain and decreases the amount of required analgesia. In particular, the amount of opiate analgesia required is considerably less.

Calcific myonecrosis: keys to recognition and management.

OBJECTIVE: Calcific myonecrosis masses can become quite large and worrisome for malignancy. The key to recognition is a combination of radiologic imaging features and remote clinical history of injury associated with compartment syndrome or vascular or neurologic compromise. CONCLUSION: This article will highlight importance of correct diagnosis by identifying the severe and devastating complications following inappropriate management.