Citations

A perception that living donor liver transplantation can be accomplished with an acceptable donor complication rate and recipient survival rate has led to the acceptance of living donor liver transplantation as a viable alternative to decreased deceased donor transplantation. Careful candidate evaluation and selection has been crucial to the success of this procedure. Advancements in the understanding of the lobar nature of the liver and of liver regeneration have advanced the surgical technique. Initial attempts at adult-to-adult donation utilized the left hepatic lobe, but now have evolved into use of the right hepatic lobe. Size matching is very important to successful graft function in the recipient. There is great concern regarding morbidity and mortality in donors. Biliary complications and infections continue to be among the most highly reported complications, although rates vary among centers and countries. Reports of single center complications have ranged from 9% to 67%. A survey of centers in the United States in 2003 reported complications of 10%. A series from our institution reported complications arising in 13 (33%) of 39 patients. A review focused on documenting donor deaths found 33 living liver donor deaths worldwide. The much publicized immediate postoperative mishap of 2002 that resulted in a donor’s death resulted in a drop in the utilization of living donor liver transplantation in the United States, from which this procedure has never fully recovered. The future development and expansion of living donor liver transplantation depends on open communication regarding donor complications and deaths. Close immediate postoperative monitoring and meticulous management will remain an essential aspect in limiting donor complications and deaths.

Abstract It is now widely accepted that a spectrum of somatic alterations occur in human cancer and that particular alterations are associated with response or lack of response to anti-cancer therapies. Here, we undertook a systematic correlation analysis of somatic mutations, copy number aberrations and drug response across 300+ human cancer cell lines. We studied the RAF and VEGFR inhibitor, sorafenib, evaluating associations between sorafenib response and somatic mutations in 35 common cancer genes and high-level amplifications and homozygous deletions in more than 100 minimal common regions of gain and loss, which include many known oncogenes and tumor suppressor genes. Notably, we found that NRAS mutations, among other alterations, were significantly associated with sensitivity to sorafenib (odds ratio = 7, p-value = 0.003), whereas activating BRAF mutations were strongly associated with a lack of response (odds ratio = 4.9, p-value = 0.012). Specifically, 64% (7 of 11) of NRAS mutant cell lines were sensitive to sorafenib, while only 20% (34 of 170) of NRAS wild-type lines were sensitive. On the contrary, just 6.7% (2 of 30) of BRAF mutant lines were sensitive to sorafenib. Because NRAS mutations occur frequently in leukemia and no leukemia cell lines were included in the original analysis, we selected 5 NRAS mutant and 5 NRAS wild-type leukemia cell lines for further evaluation. Consistent with our previous observation, the four most sensitive leukemia cell lines were all NRAS mutant, each line exhibiting greater than 50% growth inhibition after 72 hours of exposure to 4μM sorafenib. These results confirm the original association and suggest that across both solid tumors and hematologic malignancies, NRAS mutations may identify a subset of cancers that are likely to respond sorafenib. In addition, this work demonstrates that systematic analysis of somatic alterations and drug response across a large collection of cancer cell lines is capable of discovering novel predictive biomarkers. Citation Information: Clin Cancer Res 2010;16(7 Suppl):A41

Abstract Prevention of colorectal cancer (CRC) by screening hinges on the effective detection of precancers. As no conventional screening method fully prevents cancer across the colorectum, there is justification and incentive to consider alternative and complementary approaches. Precancers as Targets for Screening. In addition to curable stage CRC, precancers at greatest risk of progression are the critical screening targets. Adenomas likely account for 70-80% of CRC. While roughly 50% of Americans will acquire adenomas in their lifetime, only 6% develop CRC; so most adenomas do not progress. Advanced adenomas (those ≥1cm or containing high-grade dysplasia or prominent villous histology) appear to confer the highest risk and are generally considered to be the relevant subset for screening. Serrated polyps (sessile serrated adenomas, serrated adenomas, large hyperplastic polyps) are increasingly recognized as important precursors to CRC, especially on the right side. They account for 20-30% of CRCs, are often flat and endoscopically inconspicuous, harbor mutated BRAF and multiple hypermethylated genes, may have a more aggressive natural history, and have routinely been excluded or ignored as outcomes in screening studies1, 2. Flat dysplasia, as occurs sporadically and with inflammatory bowel disease, can be especially difficult to detect endoscopically and may often go undetected until CRC develops. Finally, field changes (molecular alterations occurring prior to phenotypic transformation) represent a largely unexplored target for screening. Limitations of Conventional Screening Tools. The commonly used screening tools have proven to be insensitive for colorectal precancers, especially right-sided ones. Such proximal lesions are above the reach of sigmoidoscopy, which has no effect on incidence of proximal CRC3. Fecal blood tests miss most precancers irrespective of their location4,,5 and have little of no effect on CRC prevention6. Because hemoglobin degrades during colon transit, commonly-used fecal blood tests, such as guaiac cards or FIT, are proportionately less sensitive for right-sided CRC5, 7. And, based on surprising recent reports8,, 9 even colonoscopy as historically practiced may fail to reduce incidence and mortality of right-sided CRC; and this may, in part, be explained by missed serrated polyps. Stool DNA Testing. As extensively reviewed,10 stool assay of exfoliated molecular markers from stool represents a noninvasive, biologically rational, and feasible strategy that continues to evolve technologically. Based on multicenter studies with early sDNA test approaches7,, 11 the American Cancer Society and other organizations endorsed sDNA testing for CRC screening12. Next-generation stool DNA (sDNA) test methods incorporate sample stabilization, the requisite analytical sensitivity to detect pre-cancers at high rates, and broad marker coverage. In a recent tissue study, panels of just 3-4 methylated DNA markers provide complete discrimination between normal colon and CRC or adenomas13. Various sDNA test approaches using new technologies in selected patients have detected 81-100% of CRC. Application of next generation sDNA testing for detection of three critical types of CRC precursors will be the major focus of this brief update. Adenomas. Based on recent reviews10,, 14 various nonoptimized stool DNA tests detect 44-86% of advanced adenomas at specificities of 85-96%. In a comparison on archival stools from a multicenter study,15 analytically sensitive next-generation methods detected significantly more advanced adenomas detection than did early sDNA tests. In a preliminary report using a multimarker next-generation assay,16 we observed that the detection rate increases with size and degree of dysplasia: 62% if ≥1cm, 78% if ≥2cm, and 90% if ≥3cm (comparable to CRC detection); and >80% of adenomas with high-grade dysplasia were detected. In contrast to fecal blood tests which are less sensitive for proximal than distal neoplasms, lesion site does not affect stool DNA test results7. Thus, regardless of anatomic site, adenomas with highest risk of progression appear to be the ones most likely to be detected by sDNA testing. Serrated Polyps. In a preliminary report,17 our group recently showed that advanced serrated polyps (i.e., those ≥1cm) can be detected noninvasively by sDNA testing. Using archived stools from a multicenter screening study, assay of mutated BRAF, methylated vimentin, or the combination detected 50%, 57%, and 71% of sessile serrated adenomas ≥1cm compared to just 7% by prospectively performed Hemoccult or HemoccultSensa (p<0.01) at comparable specificities. Large prospective studies are clearly needed to corroborate and extend these early findings. IBD-related Dysplasia. Conventional colonoscopy surveillance in patients with inflammatory bowel disease (IBD) has limited sensitivity for both premalignant dysplasia and CRC. In a preliminary report,18 our group presented findings from an ongoing multicenter study evaluating sDNA testing for detection of IBD-related neoplasia. We found that stool assay of methylated EYA4 detected 5/5 (100%) of CRCs and 4/5 (80%) of dysplasia at a 90% specificity (using colonoscopy or resected surgical specimens as criterion standards). Thus, sDNA testing appears to be feasible for the noninvasive detection of neoplasia in setting of IBD and could have an important complementary role in surveillance. Further evaluation of sDNA testing for noninvasive screening of IBD-related neoplasia are warranted Optimization and clinical validation of multimarker next-generation sDNA tests for detection of CRC, advanced adenomas, and serrated polyps in the screen setting are currently underway. References: 1. Noffsinger AE. Serrated polyps and colorectal cancer: new pathway to malignancy. Annu Rev Pathol 2009;4:343-64. 2. Lu FI et al. Longitudinal outcome study of sessile serrated adenomas of the colorectum: an increased risk for subsequent right-sided colorectal carcinoma. Am J Surg Pathol;34:927-34. 3. Atkin WS et al. Once-only flexible sigmoidoscopy screening in prevention of colorectal cancer: a multicentre randomised controlled trial. Lancet;375:1624-33. 4. Ahlquist DA et al. Accuracy of fecal occult blood screening for colorectal neoplasia. A prospective study using Hemoccult and HemoQuant tests. Jama 1993;269:1262-7. 5. Morikawa T et al. A comparison of the immunochemical fecal occult blood test and total colonoscopy in the asymptomatic population. Gastroenterology 2005;129:422-8. 6. Heresbach D et al. Review in depth and meta-analysis of controlled trials on colorectal cancer screening by faecal occult blood test. Eur J Gastroenterol Hepatol 2006;18:427-33. 7. Ahlquist DA et al. Stool DNA and occult blood testing for screen detection of colorectal neoplasia. Ann Intern Med 2008;149:441-50, W81. 8. Baxter NN et al. Association of colonoscopy and death from colorectal cancer. Ann Intern Med 2009;150:1-8. 9. Brenner H et al. Protection from right- and left-sided colorectal neoplasms after colonoscopy: population-based study. J Natl Cancer Inst;102:89-95. 10. Ahlquist DA. Molecular detection of colorectal neoplasia. Gastroenterology 2010;138:2127-39. 11. Imperiale TF et al. Fecal DNA versus fecal occult blood for colorectal-cancer screening in an average-risk population. N Engl J Med 2004;351:2704-14. 12. Levin B et al. Screening and Surveillance for the Early Detection of Colorectal Cancer and Adenomatous Polyps, 2008: A Joint Guideline from the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology. CA Cancer J Clin 2008. 13. Zou H et al. Sensitive quantification of methylated markers with a novel methylation specific technology. 2010. 14. Ahlquist DA. Next-generation stool DNA testing: expanding the scope. Gastroenterology 2009;136:2068-73. 15. Zou H et al. High detection rates of colorectal neoplasia by stool DNA testing with a novel digital melt curve assay. Gastroenterology 2009;136:459-70. 16. Zou H JX et al. Quantitative stool DNA testing for detection of both colorectal cancer and advanced adenoma. Presented at DDW 2009. 17. Hussain FT et al. Noninvasive Detection of Serrated Colorectal Polyps by Stool Assay of Methylated Vimentin and Mutant BRAF Genes. Presented at DDW 2010. 18. Kisiel JB et al. Noninvasive Detection of Colorectal Neoplasia in Inflammatory Bowel Disease by Stool DNA Testing: A Pilot Study. Presented at DDW 2010. Citation Information: Cancer Prev Res 2010;3(12 Suppl):CN13-03.

Abstract Purpose: SR13668, an orally active AKT pathway inhibitor, has demonstrated cancer chemopreventive potential in preclinical studies. To accelerate the clinical development of this promising agent, we designed and conducted the first-ever phase 0 chemoprevention trial to evaluate and compare the effects of food and formulation on SR13668 bioavailability. Patients and Methods: Healthy adult volunteers were randomly assigned to receive a single 38-mg oral dose of SR13668 in one of five different formulations, with or without food. Based on existing animal data, SR13668 in a PEG400/Labrasol@ oral solution (formulation 1) was defined as the reference formulation. Four self-emulsifying solid dispersion test formulations in capsules were also investigated: Solutol@ HS 15 (formulation 2), Solutol@ HS 15/Vitamin E TGPS (50/50 w/w %) (formulation 3), Vitamin E TGPS (formulation 4), and Myrj 53 (formulation 5). SR163668 bioavailability was compared using a two-stage study design. In stage I, participants were randomized to receive the formulation 1 with or without a high-fat meal after an overnight fast. In Stage II, participants were randomly assigned to receive the test formulations, using the preferred dietary condition identified in stage I. Blood samples were obtained pre- and post-agent administration for pharmacokinetic analyses. Area under the plasma concentration-time curve (AUC) was defined as the primary endpoint. Data were analyzed and compared using established statistical methods for phase 0 trials with a limited sample size. Results: Participants (N=20) were rapidly accrued over a 5-month period. Complete pharmacokinetic data were available for 18 randomized participants. The time to peak plasma concentration and half-life values for SR13668 were 3 hours (range, 2 — 6 hours) and 11.2 ± 3.1 hours, respectively, and were not dependent on the formulation. In stage I, the oral bioavailability of SR13668 in formulation 1 was greater under the fed versus fasting dietary state (p = 0.05, Wilcoxon rank-sum test). Therefore, the fed state was selected as the preferred dietary condition for stage II. In stage II, the bioavailability of SR13668 for each of the test formulations were compared with the bioavailability of formulation 1 in the fed state. While not significantly different from formulation 1, formulation 2 AUC0-24h was significantly different (p = 0.004, ANOVA) from formulation 3, 4, and 5 (AUC0-24h, formulation 1- 222 ± 53 ng/ml·hr; AUC0-24h, formulation 2 — 302 ± 78 ng/ml·hr; AUC-177±39ng/ml·hr; AUC-144±29 0-24h, formulation30-24h, formulation 4 ng/ml·hr; AUC0-24h, formulation 5- 98 ± 21 ng/ml·hr). Formulation 1 AUC0-24h was almost 40% lower than the value achieved with formulation 2, and not significantly different from formulation 3, 4, and 5. Thus, formulation 2 provided the highest bioavailability of SR13668. Conclusions: Using a novel, highly efficient study design, we rapidly identified a lead formulation (Solutol@ HS 15) of SR13668 for further clinical testing. Our findings support application of the phase 0 trial paradigm to accelerate chemoprevention agent development. Supported by NIH grants N01-CN-35000, CA15083-34C3 and UL1 RR024150. Citation Information: Cancer Prev Res 2010;3(12 Suppl):CN02-03.

Abstract Background. Breast density assessed from mammography is a strong predictor of breast cancer risk, but the strength of the association may vary with adiposity. To examine effect modification by adiposity, we combined data from four case-control studies on breast density that represented an ethnically diverse population with a wide variation in level of adiposity as measured by body mass index (BMI, kg/m2). Methods. We combined data from four case-control studies representing different locations: California, Hawaii and Minnesota in the United States, and Gifu in Japan. All studies included incident breast cancer cases diagnosed between 1994 and 2002 and matched controls representing the underlying case population. One mammographic image per subject was selected, specifically the mammogram at diagnosis for the studies from California, Minnesota, and Japan and the closest prediagnostic mammogram for Hawaii. Percent density was measured by one reader, who was blinded to case status, using a computer-assisted method. Self-reported anthropometric measures were used to classify women as normal, overweight, and obese according to ethnic-specific BMI cut points (<23, 23-27.4, and ≥27.5 for Asian women and <25, 25-29.9, and ≥30 for other ethnic groups). Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI) and to evaluate interactions using the likelihood ratio while adjusting for potential confounders, including age and ethnicity. Heterogeneity across studies was marginally significant as assessed by examining density-by-study interaction (P = 0.09) and, therefore, we also adjusted for study-site. Results. The study included 1,699 cases and 2,422 controls of diverse ethnicity: 45% Caucasian, 40% Asian, 9% African-American, and 7% Other. Of these women, we classified 34% as overweight and19% as obese. Age-adjusted mean percent density was significantly greater for cases than for controls: 31.7% versus 28.9%, respectively (P < 0.001). BMI was inversely associated with breast density; the estimated age-adjusted mean percent density was 36.5%, 26.8%, and 19.3% for normal, overweight, and obese, respectively (Ptrend < 0.001). The overall OR for a 10% higher percent density was 1.15 (95% CI: 1.05, 1.18) with higher estimates in overweight (OR: 1.19, 95% CI: 1.09, 1.29) and obese (OR: 1.25, 95% CI: 1.11, 1.41) than normal BMI (OR: 1.11, 95% CI: 1.05, 1.18). The effect modification by BMI was statistically significant (Pinteraction = 0.01). Conclusions. Our findings confirm that the elevated risk of breast cancer associated with breast density differs by level of adiposity, with a higher risk for overweight and obese than normal BMI. Further research is needed to understand the underlying biological reasons for these noted differences in association by adiposity. Citation Information: Cancer Prev Res 2010;3(12 Suppl):B25.

Abstract Background: Epithelial proliferation in benign breast disease (BBD) is a well-established biomarker of breast cancer risk, and BBD tissues can be used as a platform to assess other biomarkers for breast cancer risk. Lobular involution (the degree of age-related atrophy in lobules) is a new biomarker, with greater degrees of involution associated with lower breast cancer risk. Successful application of tissue biomarkers of risk to breast tissues from normal women would be valuable for risk prediction in the general population. We hypothesized that normal breast tissue samples would differ from BBD tissues in these histologic features of breast cancer risk, with less epithelial proliferation but a similar degree of involution compared to BBD tissues. Methods: Core biopsy samples from the Mayo Benign Breast Disease Cohort Study were compared to core biopsy samples of normal breast tissue obtained from the Susan G. Komen for the Cure Tissue Bank at IU Simon Cancer Center (KTB), a unique resource of breast tissue from donor women without any known breast abnormalities. All core biopsies were assessed histologically by a single breast pathologist for degree of epithelial proliferation (classified as non-proliferative, proliferative without atypia, or atypical hyperplasia) and extent of lobular involution (classified as none, 1-24%, 25-74%, or >75% of lobules). Data were analyzed using chi-square tests and logistic regression. Results: Overall, 318 Mayo BBD and 303 normal (KTB) core breast biopsy samples were evaluated. As anticipated, significantly less epithelial proliferation was present in normal samples compared to BBD samples. Proliferative disease occurred in 9/303 (3%) of normals versus 79/318 (25%) of BBD, and atypical hyperplasia was seen in 2/303 (0.7%) of normal samples versus 24/318 (8%) of BBD core biopsies, p < 0.0001. This difference remained significant after adjusting for age (which was greater overall in the BBD samples). Complete involution was more frequent in normal compared to BBD tissues, although the difference did not reach statistical significance. The age-adjusted odds ratio of complete involution in normal versus BBD tissues was 1.46 (95% CI 0.98-2.17, p = 0.06), suggesting a possible delay or failure of involution in women with BBD. Conclusions: Histologic features of normal breast tissues are different from those of BBD tissues, with less epithelial proliferation and more lobular involution, consistent with a lower risk of breast cancer expected for women with normal breast tissue compared to those with benign breast disease. Normal breast tissues are a valuable and distinct resource that should be considered for biomarker validation studies. Citation Information: Cancer Prev Res 2010;3(12 Suppl):B23.

Abstract Pancreatic cancer is a devastating disease for which the role of dietary risk factors remains inconclusive. We evaluated fruit, vegetable, fiber, and grain consumption with pancreatic cancer risk using a clinic-based case-control design, excluding participants who reported changing their diet within 5 years prior to entering the study. Our study included 384 rapidly ascertained cases and 983 non-cases (frequency matched on age at time of recruitment (± 5 years), race, sex, and region of residence) who completed epidemiologic surveys and a 144-item food frequency questionnaire developed by the National Cancer Institute. Logistic regression was used to calculate odds ratios (OR) and 95% CIs, adjusted for age, sex, smoking, body mass index, energy intake, and alcohol consumption. Comparing highest to lowest quintiles, we observed significant (OR < 0.01) inverse associations with significant trends (ptrend < 0.01) for citrus, melon, and berries, other fruit, dark green vegetables, deep yellow vegetables, tomato, other vegetables, dry bean and pea, insoluble fiber, soluble fiber, and whole grains. Adjusting for diabetes or total sugar intake in the multivariate logistic regression model did not significantly affect results. Consuming a diet high in fruits, vegetables, fiber, and whole grains may reduce the risk of developing pancreatic cancer. Citation Information: Cancer Prev Res 2010;3(12 Suppl):A85.

Abstract Preclinical investigations have identified insulin-like growth factor (IGF) signaling as a key mechanism for cancer growth and resistance to clinically useful therapies in multiple tumor types including breast cancer. Thus, agents targeting and blocking IGF signaling have promise in the treatment of solid tumors. To identify possible mechanisms of resistance to blocking the IGF pathway, we generated a cell line that was resistant to the IGF-1R/InsR benzimidazole inhibitors, BMS-554417 and BMS-536924, and compared expression profiles of the parental and resistant cells lines using Affymetrix GeneChip Human Genome U133 arrays. Compared with MCF-7 cells, breast cancer resistance protein (BCRP) expression was increased 9-fold in MCF-7R4, which was confirmed by immunoblotting and was highly statistically significant (P = 7.13E-09). BCRP was also upregulated in an independently derived resistant cell line, MCF-7 924R. MCF-7R4 cells had significantly lower intracellular accumulation of BMS-536924 compared with MCF-7 cells. Expression of BCRP in MCF-7 cells was sufficient to reduce sensitivity to BMS-536924. Furthermore, knockdown of BCRP in MCF-7R4 cells resensitized cells to BMS-536924. Four cell lines selected for resistance to the pyrrolotriazine IGF-1R/InsR inhibitor, BMS-754807, did not have upregulation of BCRP. These data suggest that benzimidazole IGF-1R/InsR inhibitors may select for upregulation and be effluxed by the ATP-binding cassette transporter, BCRP, contributing to resistance. However, pyrrolotriazine IGF-1R/InsR inhibitors do not appear to be affected by this resistance mechanism. Mol Cancer Ther; 10(1); 117–25. ©2011 AACR.