Cheville, John C.

Abstract Gleason score 7 (GS7) prostate cancer [tumors with both Gleason patterns 3 (GP3) and 4 (GP4)] portends a significantly more aggressive tumor than Gleason score 6 (GS6). It is, therefore, critical to understand the molecular relationship of adjacent GP3 and GP4 tumor cell populations and relate molecular abnormalities to disease progression. To decipher molecular relatedness, we used laser capture microdissection (LCM) and whole-genome amplification (WGA) to separately collect and amplify DNA from adjacent GP3 and GP4 cell populations from 14 cases of GS7 prostate cancer. We then carried out massively parallel mate-pair next generation sequencing (NGS) to examine the landscape of large chromosomal alterations. We identified four to 115 DNA breakpoints in GP3 and 17 to 480 in GP4. Our findings indicate that while GP3 and GP4 from the same tumor each possess unique breakpoints, they also share identical ones, indicating a common origin. Approximately 300 chromosomal breakpoints were localized to the regions affected in at least two tumors, whereas more than 3,000 were unique within the set of 14 tumors. TMPRSS2–ERG was the most recurrent rearrangement present in eight cases, in both GP3 and GP4. PTEN rearrangements were found in five of eight TMPRSS2–ERG fusion–positive cases in both GP3 and GP4. Hierarchical clustering analysis revealed that GP3 has greater breakpoint similarity to its partner GP4 compared with GP3 from different patients. We show evidence that LCM, WGA, and NGS of adjacent tumor regions provide an important tool in deciphering lineage relationships and discovering chromosomal alterations associated with tumor progression. Cancer Res; 73(11); 3275–84. ©2013 AACR.

Abstract Tumor-associated hypoxia has been associated with malignant progression, metastasis and resistance to therapy. We studied the role of oxygen tension (pO2) in modulating the properties of cultured human prostate cancer (CaP) cells. In air, where oxygen tension (pO2) is approximately 20 kPa, cultured CaP cells expressed lower levels of transcripts associated with cancer and urologic disease; reducing pO2 to 2 kPa made these levels comparable to those in surgical CaP specimens suggesting that hypoxically cultured cells, rather than normoxically cultured cells, express genes at levels akin to those in tumor cells in situ. In human primary CaP tissue, transcripts of hypoxia-associated genes DLG7, CCNB1 and HMMR were overexpressed and associated with Gleason score and disease prognosis; this implies the potential prognostic value of these transcripts. While hypoxia affected the CaP cell proteome mostly quantitatively, it did affect expression of tumor–associated antigens and suggested the potential therapeutic relevance of the hypoxic antigenic landscape. Overall, our results suggest that hypoxia modifies cellular properties of cultured CaP cells towards a phenotype more similar to tumor cells in situ. Introduction of pO2 as a variable can constitute a tool for the identification of more effective prognostic biomarkers and development of better therapy for CaP and, possibly, other tumors. Citation Format: Christian R. Gomez, Stanimir Vuk-Pavlovic, Farhad Kosari, Jan Marie Munz, Claire Schreiber, Gaylord Knutson, Cristine Charlesworth, R. Jeffrey Karnes, John Cheville, George Vasmatzis. Prognostic value of hypoxia-associated genes in prostate cancer [abstract]. In: Proceedings of the AACR Special Conference on Advances in Prostate Cancer Research; 2012 Feb 6-9; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2012;72(4 Suppl):Abstract nr C43.

Objective To evaluate carbonic anhydrase IX ( CAIX ) expression as an independent prognostic marker for clear cell renal cell carcinoma ( ccRCC ). With recent smaller studies showing conflicting results, we aimed to update our initial analysis in 2007 with an additional 5‐year follow‐up. Patients and Methods We provided long‐term follow‐up of the same cohort used in our 2007 study (730 patients with unilateral, sporadic ccRCC treated surgically between 1990 and 1999). Associations of CAIX expression with RCC death and distant metastases were evaluated using C ox proportional hazards regression models. Results CAIX was expressed in 708 (97.0%) of the specimens; 163 tumours (22.3%) had low (≤85%) expression and 567 (77.7%) high (>85%) expression. There were 483 deaths and 265 RCC ‐specific deaths. The median follow‐up for the 247 patients still under observation was 13.8 years. Univariately, low CAIX expression was associated with an increased risk of RCC death vs high expression (hazard ratio 1.62; P < 0.001). Low CAIX expression was not statistically significantly associated with RCC death or distant metastases after adjusting for nuclear grade or coagulative tumour necrosis. Conclusion After additional long‐term follow‐up of our large cohort, our results continue to suggest that CAIX is not an independent prognostic marker for ccRCC .

ObjectivesTo evaluate risk factors associated with iatrogenic splenectomy during nephrectomy and to assess outcomes among patients undergoing nephrectomy for renal tumors.MethodsOf 4323 patients who underwent nephrectomy at Mayo Clinic between 1992 and 2008, 33 (0.8%) had an iatrogenic/unplanned splenectomy. In a case–control study design, controls without splenectomy were matched 1:3 based on age, sex, surgical date, side of the renal tumor, surgical approach and surgeon. Perioperative features and survival were evaluated using conditional logistic and Cox regression.ResultsAmong the 33 iatrogenic splenectomy patients, the majority (94%) underwent radical, open and left‐sided nephrectomy. Primary tumor classification ≥T3 was the only clinicopathological risk factor significantly associated with splenectomy (odds ratio 3.4; P = 0.02). Compared with controls, patients with an iatrogenic splenectomy were more likely to have longer operative time (205 vs 171 min; P = 0.02), higher estimated blood loss (1.3 vs 0.3 L; P = 0.001), longer length of stay (median 7 vs 5 days; P = 0.03) and a higher likelihood for postoperative complications (odds ratio 5.3; P = 0.002). With a median of 9.8 years of follow up, splenectomy patients tended to have greater all‐cause mortality (hazard ratio 1.6; P = 0.07), although this difference approached statistical significance.ConclusionsIatrogenic splenectomy is a rare complication during nephrectomy and is associated with locally advanced tumors (≥pT3). It also carries prognostic significance for adverse perioperative outcomes and possibly diminished survival, although this warrants further study.