The lysine demethylase, KDM4B, is a key molecule in androgen receptor signalling and turnover.

The androgen receptor (AR) is a key molecule involved in prostate cancer (PC) development and progression. Post-translational modification of the AR by co-regulator proteins can modulate its transcriptional activity. To identify which demethylases might be involved in AR regulation, an siRNA screen was performed to reveal that the demethylase, KDM4B, may be an important co-regulator protein. KDM4B enzymatic activity is required to enhance AR transcriptional activity; however, independently of this activity, KDM4B can enhance AR protein stability via inhibition of AR ubiquitination. Importantly, knockdown of KDM4B in multiple cell lines results in almost complete depletion of AR protein levels. For the first time, we have identified KDM4B to be an androgen-regulated demethylase enzyme, which can influence AR transcriptional activity not only via demethylation activity but also via modulation of ubiquitination. Together, these findings demonstrate the close functional relationship between AR and KDM4B, which work together to amplify the androgen response. Furthermore, KDM4B expression in clinical PC specimens positively correlates with increasing cancer grade (P < 0.001). Consequently, KDM4B is a viable therapeutic target in PC.

SPRY2 loss enhances ErbB trafficking and PI3K/AKT signalling to drive human and mouse prostate carcinogenesis.

Loss of SPRY2 and activation of receptor tyrosine kinases are common events in prostate cancer (PC). However, the molecular basis of their interaction and clinical impact remains to be fully examined. SPRY2 loss may functionally synergize with aberrant cellular signalling to drive PC and to promote treatment-resistant disease. Here, we report evidence for a positive feedback regulation of the ErbB-PI3K/AKT cascade by SPRY2 loss in in vitro as well as pre-clinical in vivo models and clinical PC. Reduction in SPRY2 expression resulted in hyper-activation of PI3K/AKT signalling to drive proliferation and invasion by enhanced internalization of EGFR/HER2 and their sustained signalling at the early endosome in a PTEN-dependent manner. This involved p38 MAPK activation by PI3K to facilitate clathrin-mediated ErbB receptor endocytosis. Finally, in vitro and in vivo inhibition of PI3K suppressed proliferation and invasion, supporting PI3K/AKT as a target for therapy particularly in patients with PTEN-haploinsufficient-, low SPRY2- and ErbB-expressing tumours. In conclusion, SPRY2 is an important tumour suppressor in PC since its loss drives the PI3K/AKT pathway via functional interaction with the ErbB system.

Results of laparoscopic cryoablation in the treatment of small renal masses.

CONTEXT: Study of clinical outcome in renal cryoablation. AIMS: Laparoscopic cryoablation (LCA) is emerging as a reliable treatment option for small renal masses (SRMs) particularly in elderly patients. Our aim was to study the results of cryoablation for small renal masses in our cohort of patients. SETTINGS AND DESIGN: We retrospectively studied all patients who underwent LCA for SRMs between September 2005 and July 2008. MATERIALS AND METHODS: All patients were discussed in our multidisciplinary meeting prior to cryoablation. Our LCA protocol included two freeze-thaw cycles, achieving a core temperature of -70°C and a peripheral temperature of at least -40°C. Follow-up included serum creatinine measurements and pre- and postcontrast CT scans at 3, 6, 12, 18, and 24 months and yearly thereafter. STATISTICAL ANALYSIS USED: Paired samples t-test was used to study statistical difference. RESULTS: Twenty-two patients underwent LCA with a mean (range) age of 68 (39-81 years) years. The mean (range) tumor size was 29 (19-45 mm) mm. Two patients required blood transfusions, one patient developed pneumonia, and another patient developed a small area of skin necrosis at the cryoneedle entry site. The average (range) hospital stay was 4 (2-14 days) days. Twenty-one patients have had CT follow-up at a mean (range) of 24 (4-42 months) months. Three of the 21 tumors showed central enhancement on follow-up CT scans, consistent with treatment failure. CONCLUSIONS: Laparoscopic cryoablation is a safe treatment option for SRM in a selected group of patients.

LYRIC/AEG-1 is targeted to different subcellular compartments by ubiquitinylation and intrinsic nuclear localization signals.

PURPOSE: LYRIC/AEG-1 has been reported to influence breast cancer survival and metastases, and its altered expression has been found in a number of cancers. The cellular function of LYRIC/AEG-1 has previously been related to its subcellular distribution in cell lines. LYRIC/AEG-1 contains three uncharacterized nuclear localization signals (NLS), which may regulate its distribution and, ultimately, function in cells. EXPERIMENTAL DESIGN: Immunohistochemistry of a human prostate tissue microarray composed of 179 prostate cancer and 24 benign samples was used to assess LYRIC/AEG-1 distribution. Green fluorescent protein-NLS fusion proteins and deletion constructs were used to show the ability of LYRIC/AEG-1 NLS to target green fluorescent protein from the cytoplasm to the nucleus. Immunoprecipitation and Western blotting were used to show posttranslational modification of LYRIC/AEG-1 NLS regions. RESULTS: Using a prostate tissue microarray, significant changes in the distribution of LYRIC/AEG-1 were observed in prostate cancer as an increased cytoplasmic distribution in tumors compared with benign tissue. These differences were most marked in high grade and aggressive prostate cancers and were associated with decreased survival. The COOH-terminal extended NLS-3 (amino acids 546-582) is the predominant regulator of nuclear localization, whereas extended NLS-1 (amino acids 78-130) regulates its nucleolar localization. Within the extended NLS-2 region (amino acids 415-486), LYRIC/AEG-1 can be modified by ubiquitin almost exclusively within the cytoplasm. CONCLUSIONS: Changes in LYRIC/AEG-1 subcellular distribution can predict Gleason grade and survival. Two lysine-rich regions (NLS-1 and NLS-3) can target LYRIC/AEG-1 to subcellular compartments whereas NLS-2 is modified by ubiquitin in the cytoplasm.

Application of transcript profiling in formalin-fixed paraffin-embedded diagnostic prostate cancer needle biopsies.

OBJECTIVE: To investigate the feasibility of transcript profiling in diagnostic formalin-fixed and paraffin-embedded (FFPE) biopsies for prostate cancer. MATERIALS AND METHODS: Laser-capture microdissection (LCM) was used to microdissect glandular epithelium as well as stromal tissue in archival prostate needle biopsies. Optimized RNA extraction, reverse transcription and real-time PCR (QPCR) protocols were used to detect transcript expression. RNA degradation effects were assessed using hydrolysed cell line RNA and matched xenograft FFPE and frozen tumours. RESULTS: LCM and RNA extraction was achieved in all biopsies from a pilot cohort of five patients. cDNA produced was successfully used to detect expression of glyceraldehyde-3-phosphate dehydrogenase, RPL13, prostate-specific antigen, vimentin, inhibitor of differentiation/DNA binding 1 (Id-1) and polycomb group protein enhancer of zeste homolog 2 (EZH2) transcripts. In the cell line and xenograft models, we investigated the effect of RNA degradation on transcript quantification by QPCR. In both models normalization of transcript quantity with a housekeeping gene resulted in restored expression in all degraded samples to within a 50% difference of control samples. Using an extended cohort of 29 biopsies, we tested application in detecting differences in EZH2 and Id-1 expression between malignant and benign epithelium. The results confirmed that our technique was capable of quantifying significant differences in expression between malignant and benign epithelium consistent with the reported trends. CONCLUSION: This study reports the use of standard FFPE needle biopsies for transcript profiling and supports the concept of molecular prognostic studies in tissue acquired at diagnosis in prostate cancer.

Is continent diversion using the Mitrofanoff principle a viable long-term option for adults requiring bladder replacement?

OBJECTIVE: To audit the long-term outcome of patients with Mitrofanoff continent urinary diversion (MUD) to inform counselling of future patients concerning the procedure. PATIENTS AND METHODS: All patients who underwent MUD between 1990 and 2003 were identified. Continence, urinary tract infection (UTI), calculus formation and renal function were assessed by chart review and interviews. RESULTS: Of the 29 patients identified 12 were women and 17 men with a mean (range) age of 48 (18-79) years at operation. The median (range) follow-up was 126 (5-190) months. On questioning, 25 of 28 (89%) patients stated that they were continent. There was more than one confirmed UTI per year in two patients. Half of the patients had at least two UTIs within the follow-up period but with no deterioration in renal function. Calculi developed in eight (29%) patients; four with bladder, three with renal and one with both renal and bladder calculi. Stomal stenosis developed in 15 (54%) patients requiring intervention at a mean (range) rate of 0.4 (0.1-2.4) episodes per year and nine ultimately required stomal reconstruction. Five (18%) patients required conversion to ileal conduit, two of these for persistent incontinence and three for recurrent stomal complications, at a mean (range) of 82 (9-140) months. CONCLUSIONS: MUD is effective in offering continence with no major deterioration of renal function; however, this needs to be balanced against the need for subsequent additional interventions for stomal stenosis, stone formation and UTI on an individual basis.

Are conventional pressure-flow measurements dependent upon filled volume?

OBJECTIVE: To determine, in a prospective study, whether detrusor pressure (p(det.Qmax)) and maximum urinary flow rate (Q(max)) measurements obtained after filling to maximum cystometric capacity (MCC) differ from those obtained with filling restricted to average voided volume (V(void)), as standard protocols for pressure flow studies (PFS) mandate bladder filling until the subject has a strong desire to void, which aids standardization but further divorces the test from real-life experience. PATIENTS AND METHODS: After calculating the appropriate sample size, 84 patients attending for PFS with an adequately completed 3-day frequency-volume chart were recruited. Each underwent two consecutive PFS with filling to MCC and average V(void) in a random order, and measurements of p(det.Qmax) and Q(max) were compared. For men, the agreement for a diagnosis of obstruction between the tests was also assessed. RESULTS: Complete data were obtained from 76 (90%) of the patients, with a mean (range) age of 64 (20-94) years. The mean (sd) difference between MCC and average V(void) was 134 (113) mL (P < 0.01). There were no significant differences between estimates of Q(max), at - 0.1 (3) mL/s (P = 0.75), and of p(det.Qmax), at - 1 (13) cmH(2)O (P = 0.91), obtained within each patient. For men there was 91% agreement (32 of 35) in the classification of obstruction. CONCLUSIONS: Restriction of filling to the average V(void) during PFS allows a closer approximation to normal voiding and results in no clinically relevant change to the value of standard pressure-flow measurements or alters individual classification of obstruction.

Follicular dendritic cell sarcoma of a cervical lymph node: case report and review of the literature.

Follicular dendritic cell sarcoma is a rare tumor that occurs mainly in lymph nodes. We report a case of follicular dendritic cell sarcoma in a cervical lymph node that was initially diagnosed as a B-cell lymphoma by Tru-Cut biopsy. The correct diagnosis was established by excision biopsy and immunohistochemistry. This tumor is of interest to head and neck surgeons because its recurrence rate is significant and its metastatic potential has been underestimated because of its rarity and the difficulty in making the diagnosis. We discuss the salient clinical and pathologic features of this tumor, as well as its management protocol, and we review the literature.