Search

Cyclic GMP responses in transverse colon biopsies in subjects receiving linaclotide (Active) or placebo.

Incidence of adverse events by study age.

Cyclic GMP responses in rectal biopsies in subjects receiving linaclotide (Active) or placebo.

Polyphenon E (Poly E) is a green tea polyphenol preparation whose most active component is epigallocatechin gallate (EGCG). We studied the cancer preventive efficacy and safety of Poly E in subjects with rectal aberrant crypt foci (ACF), which represent putative precursors of colorectal cancers. Eligible subjects had prior colorectal advanced adenomas or cancers, and had ≥5 rectal ACF at a preregistration chromoendoscopy. Subjects (N = 39) were randomized to 6 months of oral Poly E (780 mg EGCG) daily or placebo. Baseline characteristics were similar by treatment arm (all P >0.41); 32 of 39 (82%) subjects completed 6 months of treatment. The primary endpoint was percent reduction in rectal ACF at chromoendoscopy comparing before and after treatment. Among 32 subjects (15 Poly E, 17 placebo), percent change in rectal ACF number (baseline vs. 6 months) did not differ significantly between study arms (3.7% difference of means; P = 0.28); total ACF burden was also similar (−2.3% difference of means; P = 0.83). Adenoma recurrence rates at 6 months were similar by arm (P > 0.35). Total drug received did not differ significantly by study arm; 31 (79%) subjects received ≥70% of prescribed Poly E. Poly E was well tolerated and adverse events (AE) did not differ significantly by arm. One subject on placebo had two grade 3 AEs; one subject had grade 2 hepatic transaminase elevations attributed to treatment. In conclusion, Poly E for 6 months did not significantly reduce rectal ACF number relative to placebo. Poly E was well tolerated and without significant toxicity at the dose studied.Prevention Relevance:We report a chemoprevention trial of polyphenon E in subjects at high risk of colorectal cancer. The results show that polyphenon E was well tolerated, but did not significantly reduce the number of rectal aberrant crypt foci, a surrogate endpoint biomarker of colorectal cancer.

Pre-Intervention Colonoscopy/Endoscopy Results.

Post intervention colonoscopy/endoscopy results.

Cyclic GMP responses in cecal biopsies in subjects receiving linaclotide (Active) or placebo.

Baseline Physical Exam.

Supplementary Table 1

ImportancePatients with familial adenomatous polyposis (FAP) are at markedly increased risk for duodenal adenomas and cancer. Combination sulindac and erlotinib was previously shown to reduce duodenal polyp burden but was associated with a relatively high adverse event (AE) rate. Objective: To evaluate if a once weekly dosing schedule for erlotinib intervention improves the AE profile, while still providing efficacy with respect to reduced polyp burden, in participants with FAP. Design, setting and participants: Single-arm trial, enrolling 46 participants with FAP, conducted from October 2017 to September 2019 in eight academic cancer centres.ExposuresParticipants self-administered 350 mg of erlotinib by mouth, one time per week for 6 months. Main outcomes and measures: Duodenal polyp burden (sum of polyp diameters) was assessed in the proximal duodenum by esophagogastroduodenoscopy performed at baseline and 6 months, with mean per cent change defined as the primary efficacy outcome of interest. Rate of grade 2–3 AEs was evaluated as a co-primary outcome. Secondary outcomes included changes in total duodenal polyp count, along with changes in lower gastrointestinal (GI) polyp burden and count (for participants examined by optional lower endoscopy).ResultsForty-six participants (mean age, 44.1 years (range, 18–68); women, 22 (48%)) were enrolled; 42 participants completed 6 months of intervention and were included in the per-protocol analysis. Duodenal polyp burden was significantly reduced after 6 months of weekly erlotinib intervention, with a mean per cent change of −29.6% (95% CI, −39.6% to −19.7%; pConclusionIn this single-arm, multi-centre trial of participants with FAP, erlotinib one time per week resulted in markedly lower duodenal polyp burden, and modestly reduced lower GI polyp burden, after 6 months of intervention. While AEs were still reported by nearly three-quarters of all participants, these events were generally lower grade and well-tolerated. These findings support further investigation of erlotinib as an effective, acceptable cancer preventive agent for FAP-associated GI polyposis.Trial registration numberNCT02961374.

BACKGROUND: Effective approaches for prevention of hepatocellular carcinoma (HCC) will have a significant impact on HCC-related mortality. Data from preclinical models strongly support epidermal growth factor receptor (EGFR) as a target for chemoprevention of HCC. Erlotinib is a small-molecular EGFR tyrosine kinase inhibitor that is FDA-approved for cancer treatment. The side effects of erlotinib observed in patients receiving the oncology dose (150 mg/day) render it unacceptable as a chemoprevention agent at this dose. OBJECTIVE: The objective of this clinical trial was determination of a safe and minimum effective dose of erlortinib for which a ≥50% reduction phospho-EGFR immunohistochemical staining in the liver was observed. RESULTS: 46 participants were pre-registered and 25 participants were registered in this multicenter trial. In a dose de-escalation trial design, cohorts of participants received a 7 day course of erlotinib 75 mg/day, 50 mg/day or 25 mg/day with liver tissue acquisition prior to and after erlotinib. A ≥50% reduction phospho-EGFR immunohistochemical staining in the liver was observed in a minimum of 40% of participants at each of the dose levels. Erlotinib was very well tolerated with few side effects observed, particularly at the dose of 25 mg/day. A favorable modulation of the Prognostic Liver Signature was observed in participants that received the higher erlotinib doses (50 and 75 mg/day). CONCLUSION: These data support the selection a dose of 25 mg/day of erlotinib for a longer intervention to assess for evidence of efficacy as an HCC chemoprevention drug. Citation Format: Kenneth K. Tanabe, David Zahrieh, Carrie A. Strand, Yujin Hoshida, Thomas J. Flotte, Gary Della’Zanna, Asad Umar, Paul Limburg. Pilot study of EGFR inhibition with erlotinib in liver fibrosis for hepatocellular carcinoma prevention [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3031.

Guanylyl cyclase C (GUCY2C) is a tumor-suppressing receptor silenced by loss of expression of the luminocrine hormones guanylin and uroguanylin early in colorectal carcinogenesis. This observation suggests oral replacement with a GUCY2C agonist may be an effective targeted chemoprevention agent. Previous studies revealed that linaclotide, an oral GUCY2C agonist formulated for gastric release, did not persist to activate guanylyl cyclase signaling in the distal rectum. Dolcanatide is an investigational oral uroguanylin analog, substituted with select D amino acids, for enhanced stability and extended persistence to activate GUCY2C in small and large intestine. However, the ability of oral dolcanatide to induce a pharmacodynamic (PD) response by activating GUCY2C in epithelial cells of the colorectum in humans remains undefined. Here, we demonstrate that administration of oral dolcanatide 27 mg daily for 7 d to healthy volunteers did not activate GUCY2C, quantified as accumulation of its product cyclic GMP, in epithelial cells of the distal rectum. These data reveal that the enhanced stability of dolcanatide, with persistence along the rostral-caudal axis of the small and large intestine, is inadequate to regulate GUCY2C across the colorectum to prevent tumorigenesis. These results highlight the importance of developing a GUCY2C agonist for cancer prevention formulated for release and activity targeted to the colorectum.

Difluoromethylornithine (DFMO), an inhibitor of polyamine synthesis, was shown to act synergistically with a NSAID for chemoprevention of colorectal neoplasia. We determined the efficacy and safety of DFMO plus aspirin for prevention of colorectal adenomas and regression of rectal aberrant crypt foci (ACF) in patients with prior advanced adenomas or cancer. A double-blinded, placebo-controlled trial was performed in 104 subjects (age 46–83) randomized (1:1) to receive daily DFMO (500 mg orally) plus aspirin (325 mg) or matched placebos for one year. All polyps were removed at baseline. Adenoma number (primary endpoint) and rectal ACF (index cluster and total) were evaluated at a one year colonoscopy. ACF were identified by chromoendoscopy. Toxicity was monitored, including audiometry. Eighty-seven subjects were evaluable for adenomas or ACF modulation (n = 62). At one year of treatment, adenomas were detected in 16 (38.1%) subjects in the DFMO plus aspirin arm (n = 42) versus 18 (40.9%) in the placebo arm (n = 44; P = 0.790); advanced adenomas were similar (n = 3/arm). DFMO plus aspirin was associated with a statistically significant reduction in the median number of rectal ACF compared with placebo (P = 0.036). Total rectal ACF burden was also reduced in the treatment versus the placebo arm relative to baseline (74% vs. 45%, P = 0.020). No increase in adverse events, including ototoxicity, was observed in the treatment versus placebo arms. While adenoma recurrence was not significantly reduced by one year of DFMO plus aspirin, the drug combination significantly reduced rectal ACF number consistent with a chemopreventive effect.

Prior research strongly implicates gastric acid and bile acids, two major components of the gastroesophageal refluxate, in the development of Barrett's esophagus and its pathogenesis. Ursodeoxycholic acid (UDCA), a hydrophilic bile acid, has been shown to protect esophageal cells against oxidative stress induced by cytotoxic bile acids. We conducted a pilot clinical study to evaluate the clinical activity of UDCA in patients with Barrett's esophagus. Twenty-nine patients with Barrett's esophagus received UDCA treatment at a daily dose of 13 to 15 mg/kg/day for 6 months. The clinical activity of UDCA was assessed by evaluating changes in gastric bile acid composition and markers of oxidative DNA damage (8-hydroxydeoxyguanosine), cell proliferation (Ki67), and apoptosis (cleaved caspase-3) in Barrett's esophagus epithelium. The bile acid concentrations in gastric fluid were measured by liquid chromatography/mass spectrometry. At baseline, UDCA (sum of unchanged and glycine/taurine conjugates) accounted for 18.2% of total gastric bile acids. After UDCA intervention, UDCA increased significantly to account for 93.4% of total gastric bile acids (P < 0.0001). The expression of markers of oxidative DNA damage, cell proliferation, and apoptosis was assessed in the Barrett's esophagus biopsies by IHC. The selected tissue biomarkers were unchanged after 6 months of UDCA intervention. We conclude that high-dose UDCA supplementation for 6 months resulted in favorable changes in gastric bile acid composition but did not modulate selected markers of oxidative DNA damage, cell proliferation, and apoptosis in the Barrett's esophagus epithelium. Cancer Prev Res; 9(7); 528–33. ©2016 AACR. See related article by Brian J. Reid, p. 512

Objective A major impediment to translating chemoprevention to clinical practice has been lack of intermediate biomarkers. We previously reported that rectal interrogation with low-coherence enhanced backscattering spectroscopy (LEBS) detected microarchitectural manifestations of field carcinogenesis. We now wanted to ascertain if reversion of two LEBS markers spectral slope (SPEC) and fractal dimension (FRAC) could serve as a marker for chemopreventive efficacy. Design We conducted a multicentre, prospective, randomised, double-blind placebo-controlled, clinical trial in subjects with a history of colonic neoplasia who manifested altered SPEC/FRAC in histologically normal colonic mucosa. Subjects (n=79) were randomised to 325 mg aspirin or placebo. The primary endpoint changed in FRAC and SPEC spectral markers after 3 months. Mucosal levels of prostaglandin E2 (PGE2) and UDP-glucuronosyltransferase (UGT)1A6 genotypes were planned secondary endpoints. Results At 3 months, the aspirin group manifested alterations in SPEC (48.9%, p=0.055) and FRAC (55.4%, p=0.200) with the direction towards non-neoplastic status. As a measure of aspirin9s pharmacological efficacy, we assessed changes in rectal PGE2 levels and noted that it correlated with SPEC and FRAC alterations (R=−0.55, p=0.01 and R=0.57, p=0.009, respectively) whereas there was no significant correlation in placebo specimens. While UGT1A6 subgroup analysis did not achieve statistical significance, the changes in SPEC and FRAC to a less neoplastic direction occurred only in the variant consonant with epidemiological evidence of chemoprevention. Conclusions We provide the first proof of concept, albeit somewhat underpowered, that spectral markers reversion mirrors antineoplastic efficacy providing a potential modality for titration of agent type/dose to optimise chemopreventive strategies in clinical practice. Trial Number NCT00468910

Guanylate cyclase C (GUCY2C) is a tumor-suppressing receptor silenced by loss of expression of its luminocrine hormones guanylin and uroguanylin early in colorectal carcinogenesis. This observation suggests oral replacement with a GUCY2C agonist may be an effective targeted chemoprevention agent. Linaclotide is an FDA-approved oral GUCY2C agonist formulated for gastric release, inducing fluid secretion into the small bowel to treat chronic idiopathic constipation. The ability of oral linaclotide to induce a pharmacodynamic response in epithelial cells of the colorectum in humans remains undefined. Here, we demonstrate that administration of 0.87 mg of oral linaclotide daily for 7 days to healthy volunteers, after oral colon preparation with polyethylene glycol solution (MoviPrep), activates GUCY2C, resulting in accumulation of its product cyclic (c)GMP in epithelial cells of the cecum, transverse colon, and distal rectum. GUCY2C activation by oral linaclotide was associated with homeostatic signaling, including phosphorylation of vasodilator-stimulated phosphoprotein and inhibition of proliferation quantified by reduced Ki67-positive epithelial cells. In the absence of the complete oral colonoscopy preparation, linaclotide did not alter cGMP production in epithelial cells of the colorectum, demonstrating that there was an effect related to the laxative preparation. These data show that the current FDA-approved formulation of oral linaclotide developed for small-bowel delivery to treat chronic idiopathic constipation is inadequate for reliably regulating GUCY2C in the colorectum to prevent tumorigenesis. The study results highlight the importance of developing a novel GUCY2C agonist formulated for release and activity targeted to the large intestine for colorectal cancer prevention. Cancer Prev Res; 10(6); 345–54. ©2017 AACR.

TPS1594Background: Colorectal cancer (CRC) remains the 4th most common cancer in the United States. Thus the identification of effective and safe prevention methods remains important. While long-te...

Background& Aims Proton pump inhibitors and nonsteroidal anti-inflammatory drugs might prevent esophageal adenocarcinoma in patients with Barrett's esophagus (BE), but there are limited data from clinical trials to support this concept. We conducted a randomized, double-blind, placebo-controlled, phase 2 trial to assess the effects of the combination of aspirin (3 different doses) and esomeprazole on tissue concentrations of prostaglandin (PG) E 2 in patients with BE with no dysplasia or low-grade dysplasia. Methods Participants were recruited through the multicenter Cancer Prevention Network and randomly assigned to groups that were given 40 mg esomeprazole twice daily in combination with an aspirin placebo once daily (arm A; n=30), with 81 mg aspirin once daily (arm B; n=47), or with 325 mg aspirin once daily (arm C; n=45) for 28 days. We collected esophageal biopsy specimens before and after the intervention period to determine the absolute change in mean concentration of PGE 2 (the primary end point). Results Based on data from 114 patients, baseline characteristics were similar among groups. The absolute mean tissue concentration of PGE 2 was reduced by 67.6 ± 229.68 pg/mL in arm A, 123.9 ± 284.0 pg/mL in arm B ( P = .10 vs arm A), and 174.9 ± 263.62 pg/mL in arm C ( P = .02 vs arm A). Conclusions In combination with esomeprazole, short-term administration of higher doses of aspirin, but not lower doses or no aspirin, significantly reduced tissue concentrations of PGE 2 in patients with BE with either no dysplasia or low-grade dysplasia. These data support further evaluation of higher doses of aspirin and esomeprazole to prevent esophageal adenocarcinoma in these patients. Clinical trial registration number NCT00474903.

Sulindac, atorvastatin, or prebiotic dietary fiber may reduce colorectal cancer (CRC) risk. However, clinical trial data are currently limited. We conducted a randomized, phase II chemoprevention trial involving subjects 40 years or older, with previously resected colon cancer or multiple/advanced colorectal adenomas. Magnification chromoendoscopy (MCE) was performed to identify and characterize rectal aberrant crypt foci (ACF); eligibility criteria required five or more rectal ACFs at baseline. Intervention assignments were as follows: (a) atorvastatin 20 mg qd; (b) sulindac 150 mg bid; (c) oligofructose-enriched inulin (as ORAFTI®Synergy1) 6 gm bid; or (d) control (maltodextrin) 6 gm bid, for 6 months. Percent change in rectal ACF number (%ΔACF) within arm was the primary endpoint. Secondary endpoints included changes in proliferation (Ki67) and apoptosis (caspase-3), as measured from normal mucosa biopsy samples. Among 85 eligible randomized subjects, 76 (86%) completed the trial per protocol. The median (range) of rectal ACF was 9 (5–34) and 8 (0–37) at baseline and postintervention, respectively. The median (SD) for %ΔACF was 5.6 (−69% to 143%), −18.6 (−83% to 160%), −3.6 (−88% to 83%), and −10.0 (−100% to 117%) in the atorvastatin, sulindac, ORAFTI®Synergy1 and control arms, respectively. Neither within-arm (P = 0.12–0.59) nor between-arm (P = 0.30–0.92) comparisons of %ΔACF were statistically significant. The active and control interventions also seemed to have similar effects on mucosal proliferation and apoptosis (P > 0.05 for each comparison). Data from this multicenter, phase II trial do not provide convincing evidence of CRC risk reduction from 6-month interventions with atorvastatin, sulindac, or ORAFTI®Synergy1, although statistical power was limited by the relatively small sample size. Cancer Prev Res; 4(2); 259–69. ©2011 AACR.

One of the major questions in preclinical testing of potential cancer preventive agents is how to most closely approximate the testing protocol to be employed in phase III prevention trials. The nature of tumors arising in situ in animals allows one to initiate agent exposure from the time of tumor initiation until the time that preinvasive lesions already exist. The large phase III prevention trials have routinely followed participants for 3 to 7 years until a cancer endpoint, which generally implies that the timing of the intervention occurs further along during tumor progression. The objective of preclinical testing is to identify agents for large-scale phase III trials. Accordingly, initiating the tested intervention in preclinical studies later in the tumor progression process is more appropriate for any agent being proposed for phase III clinical trials. Furthermore, cancer, rather than advanced dysplastic lesions or other molecular markers (gene or protein expression), is the preferred primary endpoint. However, simultaneous examination of earlier designated "intermediate" endpoints (hyperplasias, dysplasias, or molecular markers) to determine whether their modulation correlates with that of the primary tumor endpoint would be useful, since these latter endpoints may be employed in phase II prevention trials.

G A A b st ra ct s had ≥1 adenoma at repeat colonoscopy. Compared to no-therapy, patients exposed to metformin-only had a lower risk of adenoma recurrence irrespective of exam indication (screening, n= 622, HR=0.69 CI: 0.51-0.93; surveillance n= 1308, HR=0.88 CI: 0.71-1.08; diagnostic n=667, HR=0.58 CI: 0.41-0.84). However, the association was not statistically significant in patients who underwent surveillance exams. Conclusion: Metformin use was associated with a reduced risk of recurrent or new primary adenoma after polypectomy. If confirmed in further studies in other subgroups of patients and in randomized trials, metformin could have an important role in the secondary prevention of colorectal adenomas.

BACKGROUND AND AIM: In the early stages of tumorigenesis, transforming growth factor (TGF)-β1-driven signaling provides tumor-suppressive action. TGF-β1 activity is inhibited by SMAD7, a protein that binds to TGFβ receptor and prevents TGF-β1-induced signal transduction. Forced expression of SMAD7 in cancer cells differently regulates tumorigenesis depending on the cell context analyzed, and preliminary evidence suggests that amplification of SMAD7 associates with a significantly worse prognosis in patients with colorectal cancer (CRC). In this study we evaluated the role of SMAD7 in the process of colon carcinogenesis. METHODS: SMAD7 expression was evaluated in human CRC samples, CRC cell lines (i.e. HCT-116, DLD-1, HT-29 and HT-115) and normal colonic epithelial cells by immunohistochemistry and Western blotting. HCT-116 and DLD-1 cells were transfected with a specific oligonucleotide antisense (GED-0301) or control sense, and cell proliferation, cell cycle, caspase-3 activation and apoptosis were then evaluated by flow-cytometry. Expression of cell cycle-related proteins (e.g., CDK2, CDC25A, cyclin D1) was assessed byWestern blotting. To evaluate the effect of SMAD7 knock-down on CRC growth in vivo, xenografts were induced in Rag1-deficient mice by subcutaneous injection of HCT-116 cells and mice were treated either with SMAD7 sense or GED-0301. RESULTS: High SMAD7 was seen in CRC samples as compared to matched normal, adjacent, colonic samples. Consistently, SMAD7 was highly expressed in several CRC cell lines but not in normal colonic epithelial cells. Transfection of HCT-116 and DLD-1 cells with GED-0301 down-regulated SMAD7 and inhibited cell growth. Cell cycle analysis revealed that silencing of SMAD7 with GED-0301 induced cells to accumulate in S phase and this effect was associated with a sustained phosphorylation of CDK2 and decreased expression of CDC25A and cyclin D1. Moreover, time-course studies revealed that GED-0301-mediated cell cycle arrest was followed by caspase-dependent induction of CRC cell apoptosis. Finally, in vivo studies showed that daily intra-peritoneal administration of GED-0301 markedly inhibited the development of HCT-116-derived xenografts. CONCLUSIONS: SMAD7 knock-down causes accumulation of CRC cells in S phase thereby promoting cell growth arrest and apoptosis. Data suggest that SMAD7 could be a promising molecular target for pharmacological intervention in CRC patients.

Background: In patients with Barrett's esophagus, chronic reflux injury and inflammation are associated with esophageal adenocarcinoma, one of the most rapidly increasing lethal cancers. Epidemiological and preclinical studies support decreased risk of esophageal adenocarcinoma with NSAID use. Gastroesophageal refluxate contents can promote carcinogenesis in Barrett's metaplasia by activating AKT, which up regulates COX-2 expression and prostaglandin biosynthesis. We recently noted that neoplastic transformation in Barrett's esophagus is associated with increased AKT expression, particularly isoform AKT1. The AIM of this study is to investigate the effect of NSAID (Aspirin) use in patients with Barrett's esophagus on AKT1 expression using frozen tissue from the randomized, phase II trial of aspirin and esomeprazole for esophageal cancer chemoprevention in Barrett's esophagus patients and to assess the functional consequences of AKT1 expression in-vitro. Methods and Results: In a subset of patients (12 of 120 patients) with Barrett's esophagus who were randomized to placebo, lower dose (81 mg) or higher dose (325 mg) Aspirin for 4 weeks, both PCR and Western blot revealed marked reduction in AKT1 expression in patients who received 325 mg of Aspirin daily compared to patients who received placebo. Our in-vitro experiments support that AKT1 expression is functionally relevant to the process of carcinogenesis in Barrett's epithelial cells. Using adenovirus to induce AKT1 expression, we show that increased AKT1 expression increases Barrett's epithelial cell growth, facilitates RAS-mediated transformation of pre-neoplastic epithelial cells and promotes colony formation. Since AKT1 is known as Warburg kinase and regulates cellular glucose uptake to support aerobic glycolysis during growth de-regulation and neoplasia, we examined the uptake of fluorescent deoxyglucose analog (2-NBDG) in Barrett's epithelial cells transduced with AKT1 adenovirus. At 48 hrs, compared to control, AKT1 overexpression resulted in increased glucose uptake both by metaplastic and neoplastic Barrett's epithelial cells. Transcriptional repression of AKT1 abrogated the 2-NBDG uptake by these cells. Finally, we did pathway specific qPCRs and noted that use of Aspirin is associated with altered expression of chromatin remodelers that could down-regulate AKT1 expression. Conclusion: Collectively, our results demonstrate that Aspirin mediated down-regulation of Warburg kinase AKT1 in patients with Barrett?s esophagus is a novel mechanism for the regulation of Barrett?s epithelial cell growth. The in-depth characterization of molecular mechanisms is currently underway. This abstract is also presented as Poster A82. Citation Format: Navtej S. Buttar, Gary W. Falk, Cathrine J. DeMars, Sonia Chowdhury, Ahmed Elebiary, Anamay Sharma, Sidhartha Chaudhry, Nathan R. Foster, Katie L. Allen Ziegler, Yvonne Romero, Norman E. Marcon, Thomas Schnell, Douglas A. Corley, Prateek Sharma, Marcia R. Cruz-Correa, Chin Hur, David E. Fleischer, Amitabh Chak, Kenneth R. DeVault, David S. Weinberg, Gary Della’Zanna, Ellen Richmond, Thomas C. Smyrk, Sumithra Mandrekar, Paul J. Limburg. Aspirin mediated downregulation of Warburg kinase AKT1 in patients with Barrett's esophagus: Implications in neoplastic transformation. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr PR-03.

Intraductal papillary mucinous neoplasms (IPMNs) account for about 7% of clinically diagnosed pancreatic neoplasm and up to 50% of all incidentally detected pancreatic cysts. Described by Oshi et al in 1982, the incidence of these mucin-producing epithelial tumors of the exocrine pancreas has been increasing. Furthermore, IPMNs are thought to be direct precursors of pancreatic ductal carcinoma (PDA), which is among the most lethal human cancers. Many of the IPMNs are detected occur in nonsurgical candidates. Those surgically resected, a significant proportion develops PDA in the pancreatic remnant and die of disseminated disease. There is currently no chemotherapy specifically approved for treating IPMNs. Erlotinib (Tarceva, OSI-774) is an anti epidermal growth factor receptor (EGFR) orally active antitumor agent for treatment of solid tumors that is used in combination with chemotherapy to treat pancreatic adenocarcinoma. A single arm, presurgical phase IIa trial using 100mg erlotinib in IPMNs patients (7-28 days prior to surgery) was conducted. Pre and post-erlotinib IPMN tissues were compared for a reduction in the EGF regulated biomarker Mucin 5AC (MUC 5AC) as the primary outcome. Secondary outcomes included clinical regression of IPMNs and quantification of the concentration of erlotinib in pancreatic tissue. Six IPMN patients were enrolled and pancreatic surgical specimens consistently showed decreased MUC5AC with erlotinib treatment. Additionally, one patient had a clinical complete response by CT criteria. No unanticipated safety issues were observed in trial participants. Overall, these preliminary results suggest erlotinib and other EGFR antagonists should be examined further for anti-IPMN activity. Citation Information: Cancer Prev Res 2010;3(12 Suppl):A67.