H&E-like histology of unstained fresh and formalin fixed breast tissue with Photo Acoustic Remote Sensing (PARS) microscopy

e12590

Background: Approximately 30% of breast cancer patients undergoing breast-conserving surgery (BCS) require re-excision(s) to obtain clear margins, causing delays in adjuvant treatment, poor aesthetic results, and increased infection rates, costs, and patient anxiety. Frozen section pathology assessment (FSA) reduces re-excision rates from 27% to 6%, but FSA extends operative times and has a false negative rate of 17%. Photo-Acoustic Remote Sensing (PARS) is a new laser-based light microscope that permits non-contact cellular resolution imaging of unstained tissues. Methods: We used an ultraviolet reflection-mode PARS microscope to study i) formalin-fixed, paraffin embedded (FFPE) breast tissue blocks, ii) unstained thin sections of FFPE invasive ductal carcinoma and ductal carcinoma in situ, iii) formalin fixed bulk surgical specimens of benign and malignant human breast tissue, and iv) benign and malignant fresh rodent mammary tissue without fixation, processing, or staining. Fresh tissues were imaged after a range of warm ischemic times and across a range of cold ischemic times in neutral phosphate buffered saline at 4°C. For each condition, an ultraviolet laser was used to excite DNA and other cellular components in these samples, and signals were captured using a continuous-wave detection laser. The PARS signal was false-colored to closely replicate traditional hematoxylin and eosin staining. Results: In all fixed tissues, PARS virtual histology images were of diagnostic quality, permitted margin assessment, and analogous to transmission light microscopy of standard hematoxylin and eosin-stained FFPE slides, achieved without tissue sectioning or tissue staining. Furthermore, PARS microscopy also provided cellular level virtual histology images in fresh breast tissue with warm and cold ischemic times ranging from twenty minutes to two hours; these images have no available clinical comparators as non-contact cellular level imaging of unprocessed fresh tissue has not previously been reported. In aggregate, we demonstrate the feasibility of PARS to provide diagnostic and margin assessment images across a range of tissues including formalin fixed and freshly resected, unstained, unprocessed breast tissue. Conclusions: PARS is a new microscope technology addressing the practical needs of intraoperative margin assessment during BCS: i) no requirement for tissue staining, ii) rapid acquisition of hematoxylin and eosin-like images without the requirement for tissue freezing, embedding, or sectioning, iii) diagnostic quality cellular resolution, and iv) assessment of resected bulk tissue margins. In principle, this technology may also permit label-free non-contact intraoperative margin assessment of the surgical cavity. These data support the clinical development and evaluation of PARS microscopic intraoperative assessment of BCS margins.

An open-label, first-in-human, phase I trial of the safety and efficacy of daily PCLX-001

TPS3656

Background: Myristoylation regulates numerous membrane-bound signal transduction pathways important in cancer biology. This modification is catalyzed by N-myristoyltransferases 1 and 2 (NMT1 and NMT2). PCLX-001 is an oral small molecule with high affinity for both NMT proteins (IC50 of 5nM and 8nM, respectively) with high bioavailability and drug-like pharmacokinetic properties. In ex vivo sensitivity screening cell lines of hematologic cancer origin were exquisitely sensitive to PCLX-001, although high sensitivities and cell killing were also seen in some solid tumor lines derived from lung, pancreas, breast, colon, and bladder carcinomas. PCLX-001 demonstrated strong preclinical single-agent antitumor activity and tolerability in vivo in subcutaneous tumor xenograft models derived from lymphoma cell lines, lung cancer cell lines, a breast cancer cell line, as well as in a patient derived xenograft model from a patient with refractory DLBCL. The primary objective of this study is to determine the MTD and/or recommended phase II dose, safety, tolerability, and pharmacokinetics of PCLX-001 as a single agent, in patients with refractory lymphomas and advanced solid tumors. The secondary objective of the study is to evaluate the preliminary single agent anti-tumor activity of PCLX-001 in the patient populations studied. Methods: This is a multicenter, open-label, phase I dose-escalation study of oral PCLX-001 comprised of two parts (dose escalation and dose expansion). Eligible patients will have: histologically-confirmed advanced solid tumor or B-cell lymphomas who have failed prior therapy and/or are not eligible for therapies; ages ≥ 18 years; adequate organ function; life expectancy of at least 12 weeks; and measurable disease. Part A (dose-escalation) patients will be accrued in cohorts of 3 to 6 patients to each dose level, starting at 20 mg daily on a 28 day cycle. Dose escalation will follow a modified Fibonacci design such that the magnitude of escalation decreases as the dose level nears the human equivalent dose of the highest non-severely toxic dose in dogs and then escalate at 1.4 times the previous dose. Dose escalation and determination of the maximum tolerated dose will be based on the occurrence of dose limiting toxicities in cycle 1. Part B will have two single agent expansion cohorts (n = 20 each) in advanced solid malignancies and relapsed/refractory B-cell lymphoma, to determine the preliminary clinical activity of PCLX-001 to determine the recommended phase II dose. The first patient on study is planned for Q3 2020.

A multicenter study comparing granulocyte-colony stimulating factors to antibiotics for primary prophylaxis of taxotere/cyclophosphamide-induced febrile neutropenia in patients with early-stage breast cancer

7001

Background: Docetaxel-cyclophosphamide (TC) adjuvant chemotherapy is commonly used in patients with early stage breast cancer (EBC). Due to the risk of febrile neutropenia (FN) with TC, primary prophylaxis with either ciprofloxacin (cipro) or granulocyte-colony stimulating factors (G-CSF) is recommended. Despite significant differences in costs (7-120 $US/course [cipro] vs. 2100-7000 $US/dose [G-CSF]) and toxicity profiles, optimal primary FN prophylaxis is unknown. We performed a pragmatic randomised trial comparing the superiority of G-CSF to cipro. Methods: EBC patients receiving TC chemo were randomized to receive cipro or G-CSF as primary FN prophylaxis. The primary outcome is a composite of either treatment-related hospitalisations or FN. Secondary outcomes included: chemo dose reductions, delays, discontinuations and incidence of C. difficile infections. Primary analysis was performed with the intention to treat (ITT) population. Results: 455 eligible patients were randomized to cipro (227) or G-CSF (228). 37/227 (16.3%) patients on cipro had a hospitalization, compared with 25/228 (11.0%) on G-CSF (Fisher’s exact test p-value=0.10). Relative risk (RR) of hospitalization for patients on G-CSF:0.68, 95%CI=0.42 to 1.09. Patients on cipro were statistically significantly more likely to be hospitalized for FN (30/227, 13.2%) vs 9/228 (4.0%) patients on G-CSF(p<0.001). RR of developing FN and being hospitalized for patients on G-CSF: 0.44, 95%CI=0.26 to 0.76. There was no significant difference between groups for chemo dose reductions, delays, and C. difficile rates. Twenty patients on cipro (8.8%) and 9 on G-CSF (3.9%) discontinued chemo early (p=0.036). RR of discontinuing chemo: 0.43, 95%CI=0.19 to 0.96. Conclusion: G-CSF was superior to cipro at reducing FN. While a trend towards reduced hospitalizations was also observed with G-CSF, it did not attain statistical significance. However, as 18 patients would need to be treated with G-CSF to prevent one hospitalization compared to cipro, this would suggest a cost of over $100000 $US to prevent a hospitalization. A formal cost-effectiveness analysis will be performed. Clinical trial information: NCT02173262, NCT02816112 .

Abstract P1-03-07: Breast cancer diagnosis is associated with relative left ventricular hypertrophy

Background: Cardiac dysfunction is a major concern for patients with breast cancer (BC) receiving adjuvant therapy. Retrospective, cross-sectional echocardiographic data suggests that patients with cancer have reduced myocardial strain prior to cancer therapy exposure. Cardiac magnetic resonance (CMR) is the gold standard imaging modality for cardiac structure and function and can also evaluate myocardial micro-architecture with T1 mapping. We hypothesized that treatment naïve patients with early-stage BC (ESBC) have abnormal myocardial tissue characteristics on CMR.

Methods: Women with newly diagnosed ESBC were prospectively recruited for CMR prior to cancer drug treatment. Those with hypertension, diabetes mellitus or prior cancer treatments were excluded. Age and sex matched healthy controls were identified from a prior prospective study. All participants underwent a non-contrast CMR scan on a 1.5T magnet. Image acquisition included cines for cardiac structure and function as well as T1 mapping using saturation recovery single-shot acquisitions. Global longitudinal strain (GLS) was derived from cine images. Demographics and imaging metrics for healthy controls and patients were compared using two-sample t-test.

Results: 106 patients with ESBC, mean age 51±9, were included along with 55 matched healthy controls. Body mass index and systolic blood pressure were similar between groups, however resting heart rate was elevated in patients compared to controls, 77±11 vs 67±11 /min respectively, p&lt;0.001 (Table 1). On CMR there was no difference in left ventricular volume or ejection fraction however global longitudinal strain was higher in patients compared to controls, -20.9±2.3 vs -19.9±3.7%, p=0.04 (Table 2). Left ventricular mass was higher compared to controls, 52±6 and 47±6 g/m2 respectively, p&lt;0.001. However myocardial T1 was similar between groups, T1=1198±27ms for controls vs 1206±46ms for patients, p=0.42.

Conclusions: The cardiac phenotype of patients with ESBC is characterized by relative left ventricular hypertrophy with normal myocardial tissue. Further understanding of the mechanisms involved may provide insight into the cardiovascular risk associated with BC diagnosis.

Table 1.Demographics Healthy Controls (n=55)Breast Cancer (n=106)P valueAge, years (SD)52(14)51(9)0.49Body mass index, kg/m2 (SD)26(5)27(6)0.38Hypertension, number00NADiabetes Mellitus, number00NAReceptor status, number (%)  NAER/PRNA92(87%) HER2NA74(70%) Triple negativeNA2(2%) Stage, number (%)  NA1NA43(42%) 2NA41(38%) 3NA23(20%) Systolic blood pressure, mmHg (SD)127(15)124(13)0.19Heart rate, /min (SD)67(11)77(11)&lt;0.001SD=standard deviation, NA=not applicable

Table 2.Cardiac Magnetic Resonance Healthy Controls (n=55)Breast Cancer (n=106)P valueLVEF, % (SD)62(4)62(5)0.91Indexed LVEDV, ml/m2 (SD)69(9)72(14)0.18Indexed LV mass, g/m2 (SD)47(6)52(6)&lt;0.001LV mass/LVEDV (SD)0.69(0.08)0.74(0.13)0.002Indexed left atrial volume, ml/m2 (SD)40(9)37(10)0.21Global longitudinal strain, % (SD)-19.9(3.7)-20.9(2.3)0.04Myocardial T1, ms (SD)1198(27)1206(46)0.42SD=standard deviation, LVEF=left ventricular ejection fraction, LVEDV=left ventricular end-diastolic volume, LV=left ventricular

Citation Format: Kirkham A, Xu L, Wang H, Chow K, Pagano JJ, White J, Haykowsky MJ, Dyck JR, Ezekowitz JA, Oudit GY, Mackey JR, Thompson RB, Pituskin E, Paterson I. Breast cancer diagnosis is associated with relative left ventricular hypertrophy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-03-07.

Abstract PD3-11: HER2/ERBB2 status in “HER2 equivocal” breast cancers by FISH and ASCO-CAP guidelines: False-positives due to heterozygous deletions of alternative control loci

Background. The ASCO-CAP guidelines for HER2 testing by fluorescence in situ hybridization (FISH) have a category, referred to as “equivocal” (average HER2 copies per tumor cell &gt;4-6 with HER2/CEP17 ratio &lt;2·0), which is neither “HER2-positive” nor “HER2-negative”. Approximately 4% - 12% of invasive breast cancers are “HER2-equivocal” based on FISH. Cancers in this category may be resolved as “negative” or “positive” by FISH alternative control probes (2013/2014 guidelines) or HER2 immunohistochemistry (IHC) (2018 update). Our objectives were to evaluate the following hypotheses: 1.) Genetic loci used as alternative controls show heterozygous deletion in a substantial proportion of breast cancers; 2.) Use of these loci for assessment of HER2 by FISH leads to false-positives; 3.) HER2 FISH false-positive breast cancer patients have outcomes that do not differ from clinical outcomes for HER2-negative breast cancer patients; and 4.) HER2-equivocal breast cancers seldom show HER2 protein overexpression (IHC 3+).

Methods. We retrospectively assessed the use of chromosome 17 p-arm and q-arm alternative control genomic sites (TP53, D17S122, SMS, RARA, TOP2A), as recommended by the 2013/2014 ASCO-CAP guidelines, in patients whose data were available through the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC)(N=1980) or whose tissues were available from the BCIRG-005 clinical trial (N=3298). We used either FDA-approved HER2 IHC (HercepTest) or laboratory-developed HER2 (10H8) IHC assays to assess HER2 protein expression.

Results. Using METABRIC we found heterozygous deletions, particularly in specific p-arm sites, were common in both HER2-amplified and HER2-not-amplified breast cancers. Use of alternative control probes from these regions to assess HER2 by FISH in “HER2 equivocal” as well as HER2-not-amplified breast cancers resulted in high rates of false-positive ratios (HER2-to-alternative control ratio &gt;2·0) due to heterozygous deletions of control p-arm genomic sites used as ratio denominators. Misclassifications of HER2 status was observed not only in breast cancers with ASCO-CAP “equivocal” status but also in breast cancers with an average of &lt;4·0 HER2 copies per tumor cell. These deletions were also identified by FISH. IHC demonstrated &lt;1% of FISH “HER2-equivocal” breast cancers in BCIRG-005 had IHC3+ immunostaining, consistent with HER2-not-amplified status. Clinical outcomes of “HER2-equivocal” breast cancer patients with HER2-to-alternative control ratio &gt;2·0 did not differ significantly from clinical outcomes of those with HER2-to-alternative control ratio&lt;2·0.

Conclusion. Using chromosome 17 p-arm alternative controls, as recommended by 2013/2014 ASCO-CAP guidelines, instead of CEP17 for resolution of “HER2 equivocal” cases, is problematic due to frequent heterozygous deletions of these loci in breast cancers. The indiscriminate use of alternative control probes to calculate a HER2 FISH ratio in “HER2-equivocal” breast cancers leads to false-positive interpretations of HER2 status resulting from unrecognized heterozygous deletions in one or more of these alternative control genomic sites and incorrect HER2 ratio determinations.

Citation Format: Press MF, Seoane JA, Curtis C, Quinaux E, Guzman R, Sauter G, Eiermann W, Mackey JR, Robert N, Pienkowski T, Crown J, Martin M, Valero V, Bee V, Ma Y, Villalobos I, Slamon DJ. HER2/ERBB2 status in “HER2 equivocal” breast cancers by FISH and ASCO-CAP guidelines: False-positives due to heterozygous deletions of alternative control loci [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD3-11.

Intratumoural expression of deoxycytidylate deaminase or ribonuceotide reductase subunit M1 expression are not related to survival in patients with resected pancreatic cancer given adjuvant chemotherapy

BACKGROUND

Deoxycytidylate deaminase (DCTD) and ribonucleotide reductase subunit M1 (RRM1) are potential prognostic and predictive biomarkers for pyrimidine-based chemotherapy in pancreatic adenocarcinoma.

METHODS

Immunohistochemical staining of DCTD and RRM1 was performed on tissue microarrays representing tumour samples from 303 patients in European Study Group for Pancreatic Cancer (ESPAC)-randomised adjuvant trials following pancreatic resection, 272 of whom had received gemcitabine or 5-fluorouracil with folinic acid in ESPAC-3(v2), and 31 patients from the combined ESPAC-3(v1) and ESPAC-1 post-operative pure observational groups.

RESULTS

Neither log-rank testing on dichotomised strata or Cox proportional hazard regression showed any relationship of DCTD or RRM1 expression levels to survival overall or by treatment group.

CONCLUSIONS

Expression of either DCTD or RRM1 was not prognostic or predictive in patients with pancreatic adenocarcinoma who had had post-operative chemotherapy with either gemcitabine or 5-fluorouracil with folinic acid.

Expression of dihydropyrimidine dehydrogenase (DPD) and hENT1 predicts survival in pancreatic cancer

BACKGROUND

Dihydropyrimidine dehydrogenase (DPD) tumour expression may provide added value to human equilibrative nucleoside transporter-1 (hENT1) tumour expression in predicting survival following pyrimidine-based adjuvant chemotherapy.

METHODS

DPD and hENT1 immunohistochemistry and scoring was completed on tumour cores from 238 patients with pancreatic cancer in the ESPAC-3(v2) trial, randomised to either postoperative gemcitabine or 5-fluorouracil/folinic acid (5FU/FA).

RESULTS

DPD tumour expression was associated with reduced overall survival (hazard ratio, HR = 1.73 [95% confidence interval, CI = 1.21-2.49], p = 0.003). This was significant in the 5FU/FA arm (HR = 2.07 [95% CI = 1.22-3.53], p = 0.007), but not in the gemcitabine arm (HR = 1.47 [0.91-3.37], p = 0.119). High hENT1 tumour expression was associated with increased survival in gemcitabine treated (HR = 0.56 [0.38-0.82], p = 0.003) but not in 5FU/FA treated patients (HR = 1.19 [0.80-1.78], p = 0.390). In patients with low hENT1 tumour expression, high DPD tumour expression was associated with a worse median [95% CI] survival in the 5FU/FA arm (9.7 [5.3-30.4] vs 29.2 [19.5-41.9] months, p = 0.002) but not in the gemcitabine arm (14.0 [9.1-15.7] vs. 18.0 [7.6-15.3] months, p = 1.000). The interaction of treatment arm and DPD expression was not significant (p = 0.303), but the interaction of treatment arm and hENT1 expression was (p = 0.009).

CONCLUSION

DPD tumour expression was a negative prognostic biomarker. Together with tumour expression of hENT1, DPD tumour expression defined patient subgroups that might benefit from either postoperative 5FU/FA or gemcitabine.

Abstract P3-17-01: Geographic variation in adverse event reporting patterns in breast cancer clinical trials

Introduction: Adverse event (AE) reporting in clinical trials (CT) informs the safety of investigational products. Once approved, safety information in the monograph and prescribing information mainly derive from CT data. Some studies have shown geographic variations in the AE reporting patterns in multinational CT; none of them assessed this variation in cancer CT. We conducted a study to analyze the geographic AE reporting patterns in two breast cancer (BC) CT conducted by Translational Research in Oncology (TRIO).

Objective: To perform a quantitative and qualitative comparison of non-serious AE (NSAE) and serious AE (SAE) reporting patterns between several geographic regions, in breast cancer CT conducted by TRIO.

Methodology: We retrospectively analyzed aggregated NSAE/SAE data (as reported by investigators) from all patients randomized in two completed phase 3, multinational CT of anticancer therapies in advanced BC. Participating countries were grouped in 7 regions according to their geographic location (East Asia, Eastern Europe, Latin America and Caribbean, Middle East and Africa, Non-Eastern Europe, North America, Oceania). Regions were kept masked and numbered from 1 thru 7. AE data were extracted from the clinical data bases. For each region we calculated the mean number of NSAE and SAE per patient (pt), the mean number of NSAE and SAE per cycle/per pt, and the percentage (%) of pt experiencing selected AE (fatigue, febrile neutropenia and emesis). Comparisons between regions were done using unequal variance t-test and Fisher´s exact test.

Results: 1,863 patients from 35 countries and 310 sites were included. Mean number of pt per region was 331. We found significant variation in the number of NSAE/SAE reported across several regions. Two regions (1 and 6) reported the highest mean number of AE while region 4 the lowest rates. The mean number of NSAE reported in region 4 is approximately 3-fold lower than regions 1 and 6 (mean NSAE 22.8 [region 1] vs. 7.9 [region 4]; p &lt;.0001; mean NSAE cycle/pt 9.7 [region 1] vs. 3.2 [region 4]; p &lt;.0001). Region 4 reported 8-fold lower rates of SAE than region 1 (mean number SAE 0.1 vs. 0.8, p&lt;.0001) (Table 1). % of pt experiencing AE fatigue, febrile neutropenia and nausea/vomiting also varied significantly across regions, especially between regions 1 and 4 (Table 2).

NSAE and SAE reporting in selected regions (regions 1 and 4) Region 1 (mean)Region 4 (mean)p-valueNSAE per pt22.87.9&lt;.0001SAE per pt0.80.1&lt;.0001NSAE per cycle/per pt9.73.2&lt;.0001SAE per cycle/per pt0.10.03&lt;.0001

Meta-analysis of individual patient safety data from six randomized, placebo-controlled trials with the antiangiogenic VEGFR2-binding monoclonal antibody ramucirumab

BACKGROUND

Ramucirumab, the human immunoglobulin G1 monoclonal antibody receptor antagonist of vascular endothelial growth factor receptor 2, has been approved for treating gastric/gastroesophageal junction, non-small-cell lung, and metastatic colorectal cancers. With the completion of six global, randomized, double-blind, placebo-controlled, phase III trials across multiple tumor types, an opportunity now exists to further establish the safety parameters of ramucirumab across a large patient population.

MATERIALS AND METHODS

An individual patient meta-analysis across the six completed phase III trials was conducted and the relative risk (RR) and associated 95% confidence intervals (CIs) were derived using fixed-effects or mixed-effects models for all-grade and high-grade adverse events (AEs) possibly related to vascular endothelial growth factor pathway inhibition. The number needed to harm was also calculable due to the placebo-controlled nature of all six registration standard trials.

RESULTS

A total of 4996 treated patients (N = 2748 in the ramucirumab arm and N = 2248 in the control, placebo arm) were included in this meta-analysis. Arterial thromboembolic events [ATE; all-grade, RR: 0.8, 95% CI 0.5-1.3; high-grade (grade ≥3), RR: 0.9, 95% CI 0.5-1.7], venous thromboembolic events (VTE; all-grade, RR: 0.7, 95% CI 0.5-1.1; high-grade, RR: 0.7, 95% CI 0.4-1.2), high-grade bleeding (RR: 1.1, 95% CI 0.8-1.5), and high-grade gastrointestinal (GI) bleeding (RR: 1.1, 95% CI 0.7-1.7) did not demonstrate a definite increased risk with ramucirumab. A higher percentage of hypertension, proteinuria, low-grade (grade 1-2) bleeding, GI perforation, infusion-related reaction, and wound-healing complications were observed in the ramucirumab arm compared with the control arm.

CONCLUSIONS

Ramucirumab may be distinct among antiangiogenic agents in terms of ATE, VTE, high-grade bleeding, or high-grade GI bleeding by showing no clear evidence for an increased risk of these AEs in this meta-analysis of a large and diverse patient population. Ramucirumab is consistent with other angiogenic inhibitors in the risk of developing certain AEs. Clinical Trial Numbers: NCT00917384 (REGARD), NCT01170663 (RAINBOW), NCT01168973 (REVEL), NCT01183780 (RAISE), NCT01140347 (REACH), and NCT00703326 (ROSE).

Beta blockers and improved progression-free survival in patients with advanced HER2 negative breast cancer: a retrospective analysis of the ROSE/TRIO-012 study

BACKGROUND

Recent retrospective studies suggest that beta-adrenergic blocking drugs (BB) are associated with improved outcomes in patients with a range of cancers. Although limited and discordant data suggest that BB may increase overall survival (OS) in localized breast cancer (BC), there is no information on the effects of BB in women with advanced BC.

PATIENTS AND METHODS

To explore the association between BB use and BC outcomes, we retrospectively reviewed ROSE/TRIO-012, a double-blinded, multinational phase III trial that randomized 1144 patients with HER2-negative advanced BC to first-line docetaxel in combination with ramucirumab or placebo. We compared progression-free survival (PFS), OS, overall response rate, and clinical benefit rate in patients who received BB to those who did not.

RESULTS

153/1144 (13%) patients received BB; 62% prior to enrolment and 38% began after enrolment. Median PFS in BB treated patients was longer than in patients who did not receive them (10.3 versus 8.3 months; HR 0.81; 95% CI 0.66-0.99; P = 0.038). Patients treated with BB only after enrolment had even higher median PFS (15.5 versus 8.3 months, P < 0.001). In the TNBC subset, median PFS was 13.0 months with BB, compared to 5.2 months without BB (HR 0.52; 95% CI 0.34-0.79; P = 0.002). The benefit of BB intake in PFS was independent of treatment-emergent hypertension (P = 0.476) but associated with treatment arm (P = 0.037). The test for interactions between BB and treatment arm was not significant (P = 0.276). No differences were seen in OS, overall response rate, or clinical benefit rate. A validation dataset analysis had consistent but less substantial improved outcomes for women with node positive operable breast cancer receiving BB in the BCIRG-005 trial.

CONCLUSIONS

In this exploratory analysis, BB intake was associated with significant improvement in PFS, particularly in patients with TNBC and patients not previously exposed to BB.

CLINICAL TRIAL NUMBER

NCT00703326.

Predictive value of hENT1 immunohistochemistry for gemcitabine-treated pancreatic cancer is antibody dependent

e15746

Background: Pancreatic cancer (PC) continues to have poor outcomes, and biomarkers to guide individualized therapy are needed. Gemcitabine (GEM), a pyrimidine nucleoside, requires plasma membrane transporter proteins to enter cells, and deficiency of the human equilibrative nucleoside transporter 1 (hENT1) protein confers high-level GEM resistance in pre-clinical models. Furthermore, abundance of hENT in PC cells, as determined by immunohistochemistry (IHC), has been variably reported to be associated with improved survival in people with PC treated with GEM. The antibodies (Abs) used for IHC differ in targeted epitope, method of generation, and species of origin. The purpose of this review is to evaluate the contribution of anti-hENT1 Ab choice in finding a link between hENT1 expression and outcomes. Methods: We reviewed the published literature investigating relationships between hENT1 IHC tumor expression and survival in people with PC treated with GEM. Results: Eighteen studies were identified, using five distinct Abs (Table 1). We identified apparent differences in predictive value among Abs (Chi square test p = 0.065). All seven studies using the 10D7G2 Ab reported that high hENT1 expression is associated with significantly better outcomes in GEM-treated patients. Studies that used other anti-hENT1 Abs, in particular SP120 and 11337-1-AP, had lower rates of success. Pooled HRs and additional metrics will be presented. Conclusions: There is significant heterogeneity among studies evaluating the link between hENT1 expression and outcomes. hENT1 IHC with the 10D7G2 Ab is a strong and reproducible predictive marker for improved survival in people with PC treated with GEM. [Table: see text]

Long-term outcomes after adjuvant treatment of sequential versus combination docetaxel with doxorubicin and cyclophosphamide in node-positive breast cancer: BCIRG-005 randomized trial

BACKGROUND

The optimal regimen for adjuvant breast cancer chemotherapy is undefined. We compared sequential to concurrent combination of doxorubicin and cyclophosphamide with docetaxel chemotherapy in women with node-positive non-metastatic breast cancer. We report the final, 10-year analysis of disease-free survival (DFS), overall survival (OS), and long-term safety.

PATIENTS AND METHODS

A total of 3298 women with HER2 nonamplified breast cancer were randomized to doxorubicin and cyclophosphamide every 3 weeks for four cycles followed by docetaxel (AC → T) every 3 weeks for four cycles or docetaxel, doxorubicin, and cyclophosphamide (TAC) every 3 weeks for six cycles. The patients received standard radiotherapy and endocrine therapy and were followed up for 10 years with annual clinical evaluation and mammography.

RESULTS

The 10-year DFS rates were 66.5% in the AC → T arm and 66.3% in the TAC arm (P = 0.749). OS was 79.9% in the AC → T arm and 78.9% in the TAC arm (P = 0.506). TAC was associated with higher rates of febrile neutropenia, although G-CSF primary prophylaxis greatly reduced this risk. AC → T was associated with a higher rate of myalgia, hand-foot syndrome, fluid retention, and sensory neuropathy.

CONCLUSION

This 10-year analysis of the BCIRG-005 trial confirmed that the efficacy of TAC was not superior to AC → T in women with node-positive early breast cancer. The toxicity profiles differ between arms and were consistent with previous reports. The TAC regimen with G-CSF support provides shorter adjuvant treatment duration with less toxicity.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT00312208.

Abstract P4-10-16: Long term effects of trastuzumab on cardiopulmonary and left ventricular function in women with HER2 overexpressing breast cancer

Background: Adjuvant trastuzumab (TRZ) is the standard of care for HER2-overexpressing (HER2+) early stage breast cancer (EBC) patients (PTS), with five-year survival rates exceeding 90%. However, significant cardiac toxicities are observed, with a fivefold increase in clinical heart failure (HF). Left ventricular (LV) remodeling (increased heart size and mass) is an early indicator of cardiac injury, progressing to further LV dysfunction, reduced exercise tolerance and overt HF. Therefore, effective prevention of such negative sequelae is of enormous clinical interest. As the pivotal TRZ trials assessed cardiac function with MUGA or echocardiography, insensitive modalities to evaluate LV remodeling, the long-term sequelae of TRZ remain unknown.

Objective: to determine the long term effects of trastuzumab on cardiopulmonary and left ventricular function in women with HER2 overexpressing breast cancer. Additionally as aerobic training is an effective intervention in HF PTS who adhere to prescribed exercise, a sub-analysis compared those who adhered during a 4 month exercise intervention (AEX) vs those who did not adhere (NEX).

Methods: 16 PTS (mean age 58 ± 7) who participated in an exercise intervention study during the first 4 months of TRZ therapy were recruited, with an average of 4 years elapsing since TRZ completion. Cardiopulmonary exercise (VO2peak) testing and resting cardiac MRI (CMR) were performed and compared with baseline and 4 month assessments. Adherence to exercise intevention was defined as attendance ≥80% prescribed sessions.

Results: All 16 PTS reported independent living with no limitations to ADLs. At 4 years, mean VO2peak for all PTS was 22.4 ml/kg/min (20.0 at baseline and 22.0 at 4 months). In AEX PTS, higher VO2peak persisted 4 years after cessation of therapy, 4.1 mL/kg/min higher than NEX PTS (24.9 and 20.8 mL/kg/min, respectively ). Mean LVEF for all PTS was 60 ± 6%, not significantly different from baseline or 4 months (61 ± 5 and 55 ± 4%, respectively) . Statistically significant interactions of exercise adherence to other CMR metrics were not observed.

Conclusions: Clinically significant impairment of cardiopulmonary function (equal to 14 years of aging) are present before therapy and persist in PTS four years following exposure to TRZ-based chemotherapy. This observation is consistent with our other work, and occurs on a background of normal LVEF, implying additional negative effects to other components of the oxygen cascade. As mortality risk has been shown to decrease by 17% for every 3.5 mL/kg/min difference in aerobic capacity in healthy females, these findings indicate adherence to exercise interventions during TRZ-based therapy has potentially important long-term implications.

Citation Format: Pituskin E, Paterson I, Ghosh S, Mackey JR, Haykowsky MJ. Long term effects of trastuzumab on cardiopulmonary and left ventricular function in women with HER2 overexpressing breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-10-16.

Abstract P6-01-01: Impact of imaging surveillance on the risk of radiation induced malignancies in breast cancer survivors

Introduction: After curative treatment of breast cancer (BC), relevant clinical guidelines recommend against the use of imaging procedures other than yearly mammography for surveillance, based on the lack of survival benefit for intensive surveillance strategies. Nevertheless, use of non-recommended imaging tests occurs frequently in this context. Most BC surveillance studies have focused on the potential benefit of detection of early relapse, on financial burden, and risk of false positives with different follow-up regimens. No study has analyzed the risk of imaging radiation induced malignancies (IRIM) in BC survivors exposed to repeated body imaging during surveillance. We previously reported on the IRIM risk in the BC clinical trials setting (Fresco R. The Oncologist 2015). In this current study we report on this risk during surveillance in clinical practice in BC survivors.

Objective: To estimate IRIM risk in patients curatively treated for BC undergoing imaging tests during surveillance.

Methodology: We defined 6 surveillance strategies with differing imaging requirements, from a non imaging-intensive one (yearly mammography only) to intensive ones (mammography + CT, Bone scan, PET-CT and/or MUGA) (Table 1). For each strategy we calculated the imaging dose and excess lifetime attributable cancer risk (LAR) for a 60 year-old BC survivor, using NCI's Radiation Risk Assessment Tool (RadRat).

Results: Total effective imaging radiation dose received by a 60 year-old BC survivor during surveillance was 8.4 miliSieverts (mSv) when only yearly mammography is performed to 199.9 mSv when CT, MUGA and bone scan are added. Mean IRIM LAR ranges from 37.2/100,000 with the first strategy to 1,330/100,000 with the latter. Performing MUGA scans increased IRIM risk 31% compared to not performing it. The addition of any additional radiating imaging procedure to yearly mammography significantly increases LAR.

Imaging effective dose and LAR in different surveillance strategiesFollow-up strategyImaging effective dose (mSv)Excess lifetime attributable cancer risk: mean (90% uncertainty range) (/100,000)Yearly mammography only8.437.2 (21.4-60.3)Yearly mammography + Chest/abdomen CT q6mo for 3y, then annually for 2y128.4857.0 (503.0-1,350.0)Yearly mammography + Chest/abdomen CT q6mo for 3y, then annually for 2y + Bone scan q12mo for 5y159.91,060.0 (603.0-1,640.0)Yearly mammography + Chest/abdomen CT q6mo for 3y, then annually for 2y + MUGA q6mo for 2y168.41,130.0 (642.0-1,800.0)Yearly mammography + Chest/abdomen CT q6mo for 3y, then annually for 2y + MUGA q6mo for 2y + Bone scan q12mo for 5y199.91,330.0 (792.0-2,080.0)Yearly mammography + PET-CT q6mo for 3y, then annually for 2y184.41,310.0 (802.0-1,990.0)

Conclusions: A number of incremental second cancers could be derived from imaging performed during BC surveillance after curative treatment. Addition of non-recommended imaging for relapse detection increases IRIM risk compared to performing only mammography. This, in addition to the lack of proven benefit in BC endpoints, emphasizes the need to follow recommendations for surveillance clinical guidelines, and forgo imaging studies other than annual mammography to detect relapses. Substituting MUGA with echocardiogram for cardiac assessment could also reduce IRIM risk.

Citation Format: Spera G, Gonzalez V, Meyer C, Fung H, Mackey JR, Fresco R. Impact of imaging surveillance on the risk of radiation induced malignancies in breast cancer survivors. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-01-01.

Abstract P6-14-03: Genome wide association study (GWAS) to identify variants conferring ramucirumab-associated hypertension in the ROSE/TRIO-012 breast cancer trial

Background: In a candidate single nucleotide polymorphism (SNP) association study, we previously identified VEGFR-1 and VEGFR-2 SNPs strongly associated with treatment emergent hypertension (HT) in the ramucirumab (RAM) and docetaxel (Doc) arm in the ROSE/TRIO-012 study, a double-blinded multinational phase III trial that randomized 1,144 patients with advanced breast cancer to receive first-line Doc in combination with RAM or placebo (Mackey et al, JCO Jan 10, 2015:141-148; Mackey et al, JCO, Volume 33, Issue 15_suppl, May 20, 2015: 547). However, candidate SNP studies limit the number of genes for interrogation and a more comprehensive genome wide search may identify critical variants associated with the phenotype of HT. Preliminary analysis indicated that patients experiencing HT with RAM showed better overall survival (Mackey JR, et al (2015). Reply to H. Lee, et al. JCO; in press). These observations provide the potential to identify those patients with genetic variants for predisposition to RAM-associated HT to inform therapeutic decisions.

Methods: Genotyping of samples is underway using Affymetrix SNP 6.0 arrays. Genotype data will be filtered for deviations from Hardy Weinberg Equilibrium and minor allele frequency of &gt;0.05. Study subjects (n=792) provided ethics-committee approved prospective consent for this genetic study of whom 478 subjects were allocated RAM + Doc arm. Toxicity grades 0-1 (n= 394 controls; low toxicity) vs. grade &gt;2 (n= 84 cases, high toxicity) is our binary outcome. Dominant genotypic model is assumed. Chi-square test, FDR and/or 10000 permutation tests will be employed (Golden Helix-SVS v8.3) and p&lt;0.05 considered statistically significant. Population stratification will be identified (EIGENSTRAT) and association statistics will be corrected using Eigenvectors along with age as covariates. Fine mapping of loci showing significant associations will be attempted using imputation tools.

Results and conclusions: We expect up to 700,000 SNPs to be retained after filtering based on our previous breast cancer GWAS analyses (Damaraju et al. Cancer Research (suppl); Vol 70 (24), page 258s, 2010 and Sehrawat et al Hum Genet. 2011 Oct;130(4):529-37) and 30,000 SNPs to show significance at a nominal p-value (0.05); these will be analysed for regions of high linkage disequilibrium to narrow down potential loci showing association with HT to serve as candidate markers in further independent validation studies. Cumulative dose to adverse events will be considered in the analysis. Identified loci will be interrogated for potential genes in the flanking regions with biological relevance based on pathway analysis. Identified variants from candidate SNP and GWAS may allow developing predictive tools to enable stratification of patients for therapies. The analysis is expected to be completed by mid- November, 2015.

Citation Format: Mackey JR, Lipatov O, Martín M, Webster M, Hegg R, Verma S, Ramos-Vázquez M, Fresco R, Thireau F, Houé V, Press MF, Kumaran M, Damaraju S. Genome wide association study (GWAS) to identify variants conferring ramucirumab-associated hypertension in the ROSE/TRIO-012 breast cancer trial. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-14-03.

Abstract P1-13-03: Genome wide association study (GWAS) of genetic variants associated with docetaxel toxicity in the ROSE/TRIO-012 trial

Background: Genetic predisposition to docetaxel (Doc) toxicity contributes to unacceptable toxicity and reduced dose intensity, and may influence disease outcomes. We previously reported variants associated with Doc toxicity in candidate gene single nucleotide polymorphism (SNP) associations in a breast cancer treatment setting (Damaraju et al. Eur J Cancer (suppl); Vol 8 (7), page 175, 2010) and the identified variants were confirmed in an independent validation study (Damaraju et al, J Clin Oncol Vol 33, Issue 15 suppl, 2015: 540). Others have reported candidate SNP (Breast Cancer Res Treat, 2011 SWOG 0221 study) and GWAS (Clin Cancer Res 2012 CALGB 40101 study) identified variants associated with paclitaxel mediated peripheral neuropathy. However, the overlap on the variants identified thus far between Doc and paclitaxel are limited, prompting a genome wide search to find variants contributing to Doc specific toxicity.

Methods: TRIO-012 is a double blinded, multinational trial that randomized 1,144 patients with advanced breast cancer to receive first-line Doc in combination with ramucirumab (RAM) or placebo (Mackey et al. J Clin Oncol Jan 10, 2015:141-148). Study subjects (n=719) in the Doc+RAM or Doc+placebo arm with available germline DNA are being genotyped; all subjects provided ethics-committee approved prospective consent for this genetic study. Genotyping are being performed with Affymetrix SNP 6.0 arrays. Genotype data will be filtered for deviations from Hardy Weinberg Equilibrium and minor allele frequency of &gt;0.05. Doc-induced adverse events (AEs) are based on CTCAE (Common Terminology Criteria for Adverse Events v4.1) toxicity grades. Toxicities &gt;2 scored for fatigue (n=96), myalgia (n=22), peripheral neuropathy (n=17) will be analysed as individual phenotypes in comparison with the no toxicity group (toxicity grades 0-1) and in a combined analysis of all Doc induced toxicities (0-1, n=599 vs. &gt;2, n=120). Dominant genotypic model is assumed; Chi-square test, FDR and/or 10000 permutations were employed using SVS v8.3 and p&lt;0.05 considered statistically significant. We will identify population stratification using EIGENSTRAT method and will correct the association statistics using the Eigenvectors along with age and BMI as covariates. Fine mapping of the identified loci will be attempted using imputation tools. We will interrogate the data for cumulative dose to toxicity and correlate SNPs identified with survival outcomes.

Results and conclusions: We expect to reconfirm the associations of loci reported in candidate SNP and previous GWAS studies; XKR4 (rs4737264) for peripheral neuropathy, CYP3A5*3 (rs776746) with fatigue, and FACND2 (rs7637888) with myalgia in addition to the potential novel variants distinct from paclitaxel AE GWAS studies. Fine mapping around these loci may help identify potential causal variants. Both candidate SNP and GWAS identified variants may aid in developing risk stratification models. The GWAS identified loci and the flanking genes will be interrogated using the ingenuity pathway analysis for insights in to the biological roles in the drug metabolism. We expect to complete the analysis by mid-November 2015.

Citation Format: Damaraju S, Gorbunova V, Gelmon K, García-Saenz J, Morales-Murillo S, AbiGerges D, Canon J-L, Kiselev I, Cohen GL, Jerusalem G, Thireau F, Fresco R, Houé V, Press MF, Kumaran M, Mackey JR. Genome wide association study (GWAS) of genetic variants associated with docetaxel toxicity in the ROSE/TRIO-012 trial. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-13-03.

Effect of aerobic training on the host systemic milieu in patients with solid tumours: an exploratory correlative study

Background:

Few studies have investigated the effects of exercise on modulation of host factors in cancer patients. We investigated the efficacy of chronic aerobic training on multiple host-related effector pathways in patients with solid tumours.

Patients and Methods:

Paired peripheral blood samples were obtained from 44 patients with solid tumours receiving cytotoxic therapy and synthetic erythropoietin (usual care; n=21) or usual care plus supervised aerobic training (n=23) for 12 weeks. Samples were characterised for changes in immune, cytokine and angiogenic factors, and metabolic intermediates. Aerobic training consisted of three supervised cycle ergometry sessions per week at 60% to 100% of peak oxygen consumption (VO_2peak), 30–45 min per session, for 12 weeks following a nonlinear prescription.

Results:

The between-group delta change in cardiopulmonary function was +4.1 ml kg ⁻¹ min⁻¹, favouring aerobic training (P<0.05). Significant pre–post between-group differences for five cytokine and angiogenic factors (HGF, IL-4, macrophage inflammatory protein-1β (MIP-1β), vascular endothelial growth factor (VEGF), and TNF-α) also favour the aerobic training group (P's<0.05). These reductions occurred in conjunction with nonsignificant group differences for T lymphocytes CD4⁺, CD8⁺, and CD8⁺/CD45RA (P<0.10). For these factors, circulating concentrations generally increased from baseline to week 12 in the aerobic training group compared with decreases or no change in the usual care group. No significant changes in any metabolic intermediates were observed.

Conclusions:

Aerobic training alters host availability of select immune–inflammatory effectors in patients with solid tumours; larger confirmatory studies in more homogenous samples are warranted.

Human equilibrative nucleoside transporter 1 (hENT1) in gemcitabine and FOLFOX (oxaliplatin, 5-fluorouracil, and leucovorin)-treated patients with metastatic pancreatic cancer: The randomized phase II PAN1 study

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Background: GEM-based treatment is a standard treatment for metastatic pancreas cancer. Monotherapy efficacy is only modest, and outcomes are improved by combination treatment or the non-GEM FOLFIRINOX triplet. There is a need for biomarkers to select between these divergent options. hENT1 is a potential predictive marker of benefit from GEM, but conflicting results have been observed in studies that have evaluated resected and metastatic pancreatic cancer. This principal objective of this study was to evaluate hENT1 prospectively as a predictive marker in GEM and non-GEM treated patients. Methods: Patients with previously untreated metastatic pancreatic adenocarcinoma and tumour tissue available for hENT1 testing were randomized between GEM (1,000 mg/m2 D1, 8, 15 Q4w) or FOLFOX (oxaliplatin 85 mg/m2, 5-fluorouracil (5FU) 400 mg/m2, leucovorin 400 mg/m2 D1 and 5FU 2,400 mg/m2over 46 hours D1-3) until disease progression or unacceptable toxicity. Tumor samples were tested prospectively for hENT1 by immunohistochemistry. The primary endpoint was progression-free survival (PFS). Results: The study was open from July 2011 to February 2013, but closed after 16 of the planned 80 patients were enrolled. 1 patient who died before treatment was excluded from the outcome analysis. 7/16 patients were hENT1 high (43.8%, 95%CI 23.1-66.8%). In the GEM arm (n=7), the 4 who were hENT1 high had longer PFS and overall survivals (OS) than those who were hENT1 low (median PFS 5.7 vs. 1.8 months; median OS 13.9 vs. 3.5 months), whereas outcomes were similar with FOLFOX for both hENT1 groups. There were no unexpected adverse events. Conclusions: This prospective study showed a longer survival in those patients with high hENT1 treated with GEM. There was no difference in survival according to hENT1 expression in patients treated with FOLFOX. Given the small sample size this may be due to chance, but supports the need for further research into the predictive value of hENT1. Clinical trial information: ACTRN12610001047088.[Table: see text]

Abstract P4-08-01: Effects of exercise during adjuvant chemotherapy on clinical outcomes in early stage breast cancer

Background: Observational studies suggest that physical activity following a diagnosis of breast cancer may be associated with a lower risk of recurrence and death. Some studies also suggest possible effect modification by disease stage, body mass index, and receptor status. To date, however, there are no randomized trials examining the effects of exercise on disease outcomes in any cancer patient group. Here, we report an exploratory follow-up of disease outcomes from the Supervised Trial of Aerobic versus Resistance Training (START). Patients and Methods: The START Trial was a Canadian multicenter trial that randomized 242 breast cancer patients starting adjuvant chemotherapy to either usual care (n = 82) or supervised aerobic (n = 78) or resistance (n = 82) exercise for the duration of their chemotherapy. The primary efficacy endpoint for this exploratory analysis was disease-free survival (DFS). Secondary endpoints were overall survival (OS), distant disease-free survival (DDFS), and recurrence-free interval (RFI). The two exercise arms were combined for the analysis (n = 160) and selected subgroups were explored. Results: After a median follow-up of 89 months (IQR 81 to 96), there were 25/160 (15.6%) DFS events in the exercise groups and 18/82 (22.0%) in the control group (log-rank p = 0.21). Eight-year DFS was 82.7% for the exercise groups compared with 75.6% for the control group (Hazard ratio [HR] = 0.68, 95% CI = 0.37-1.24). There were 13/160 (8.1%) deaths in the exercise groups and 11/82 (13.4%) in the control group (log-rank p = 0.21). Eight-year OS was 91.2% in the exercise groups compared with 82.7% in the control group (HR = 0.60, 95% CI = 0.27 to 1.33. There were 20/160 (12.5%) DDFS events in the exercise groups and 16/82 (19.5%) in the control group (log-rank p = 0.15). Eight-year DDFS was 86.7% in the exercise groups compared with 78.3% in the control group (HR = 0.62, 95% CI = 0.32 to 1.19). Finally, there were 20/160 (12.5%) RFI events in the exercise groups and 17/82 (20.7%) in the control group (Gray's p = 0.095). Eight-year cumulative incidence of RFI was 12.6% in the exercise groups compared with 21.6% in the control group (HR = 0.58, 95% CI = 0.30 to 1.11). Subgroup analyses for DFS and RFI suggested stronger effects for women who were overweight/obese, had stage II/III cancer, receptor positive tumors, HER2 positive tumors, received taxane-based chemotherapies, and received at least 85% of their intended chemotherapy dose-intensity. The most notable subgroup effect was for patients who received optimal chemotherapy dosing with a borderline significant effect for DFS (HR = 0.50, 95% CI = 0.25 to 1.01) and a significant effect for RFI (HR = 0.38, 95% CI = 0.18 to 0.81). Conclusions: In this exploratory follow-up of the START Trial, there was a suggestion that exercise during adjuvant chemotherapy may improve several efficacy endpoints although none achieved statistical significance. Nevertheless, the magnitude of the effects appear to be meaningful with absolute 8-year survival differences between 7% and 9% and relative rate reductions between 30% and 40%. The START Trial provides the first randomized data to suggest that adding exercise to standard chemotherapy for breast cancer may improve outcomes. A definitive phase III trial is warranted.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-08-01.

The effect of obesity on prognosis in operable breast cancer patients treated with adjuvant anthracyclines and taxanes according to pathologic subtypes

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Background: According to observational studies, obesity is an unfavourable prognostic factor in breast cancer (BC), regardless of menopausal status and treatment received. Information collected in clinical trials should confirm this effect and serves to test its homogeneity by pathologic subtype. Methods: We retrospectively analysed 5,683 operable BC patients enrolled in four randomized clinical trials (GEICAM/9906, 9805, 2003–02, and BCIRG 001) evaluating adjuvant anthracyclines and taxanes. Our primary aim was to assess the prognostic effect of body mass index (BMI) on disease recurrence, breast cancer mortality (BCM), and overall mortality (OM). A secondary aim was to detect differences by BC subtypes (ER/PR-positive/HER2-negative, HER2-positive, triple-negative). Cox models were fitted for each end-point, adjusted by potential confounders. Results: Analyses adjusting for age, tumor size, nodal status, menopausal status, surgery, grade, hormone receptor and HER2 status, chemotherapy regimen, and undertreatment showed that obese patients (BMI 30.0–34.9) had similar prognoses to that of patients with a BMI<25 (reference group) in terms of recurrence (HR 1.08 [95% CI 0.9–1.3]; p=0.41), BCM (HR 1.02 [0.81–1.29]; p=0.85), and OM (HR 0.97 [0.78–1.19]; p=0.747). Patients with severe obesity (BMI≥35) had a significantly increased risk of recurrence (HR 1.26 [1.00–1.59]; p=0.05), BCM (HR 1.32 [1.00–1.74]; p=0.05), and OM (HR 1.35 [1.06–1.71]; p=0.02) compared to our reference group (Table). The prognostic effect of severe obesity did not vary by subtype. Conclusions: Severely obese patients treated with anthracyclines and taxanes present a worse prognosis regarding recurrence, BCM, and OM than patients with a BMI<25. The magnitude of the harmful effect of BMI was similar across subtypes. [Table: see text]

HENT1 tumor levels to predict survival of pancreatic ductal adenocarcinoma patients who received adjuvant gemcitabine and adjuvant 5FU on the ESPAC trials

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Background: Some studies in patients with resected pancreatic cancer have suggested that expression of the human equilibrative nucleoside transporter (hENT1) may be predictive of improved survival from gemcitabine but these have either been based on retrospective non-randomized studies or in one study the principal treatment was chemoradiation. The samples collected from the adjuvant ESPAC1/3 randomized trials have provided a unique opportunity to assess to REMARK standards the therapeutic predictability of hENT1 in patients undergoing resection for pancreatic cancer. Methods: Tissue Microarrays (TMAs) were prepared using paraffin embedded tumor specimens from patients randomized to gemcitabine or 5FU/Folinic acid in the ESPAC-1 and -3 trials. Cores were given an H-Score depending on the level of staining with the 10D7G2 anti-hENT1 antibody. Groups were compared using Kaplan-Meier and Cox proportional hazards. Results: Scores were obtained for 176 gemcitabine treated and 176 5FU treated patients. The overall median H-Score was 48 and patients were classified as having high hENT1 if the mean score for their cores was above this. Median overall survival for gemcitabine treated patients was 23.4 (95% CI: 18.3, 26.0) months versus 23.5 (95% CI: 19.8, 27.3) months for 5FU treated patients (χ21 = 0.24, P = 0.623). In the gemcitabine group A significantly lower survival (χ21 = 9.87, P = 0.002) was noted with low hENT1 (median survival 17.1 (95% CI: 14.3, 23.8) versus 26.2 (95% CI: 21.2, 31.4) months). Median survival was 25.6 (95% CI: 20.1, 27.9) and 21.9 (95% CI: 16.0, 28.3) months respectively for high and low hENT1 in the 5FU group, a non-significant difference (χ21 = 0.83, P = 0.362). Multivariate analysis confirmed hENT1 expression as a predictive marker in gemcitabine (Wald χ2 = 7.10, P = 0.008) but not 5-fluorouracil (Wald χ2 =0.34, P = 0.560) groups. Conclusions: The study supports use of gemcitabine in patients with high tumor hENT1 expression and 5-fluorouracil in patients with low hENT1.

Targeting triple-negative breast cancer: optimising therapeutic outcomes

BACKGROUND

Triple-negative breast cancer (TNBC) is a distinct subset of breast cancer (BC) defined by the lack of immunohistochemical expression of the estrogen and progesterone receptors and human epidermal growth factor receptor 2. It is highly heterogeneous and displays overlapping characteristics with both basal-like and BC susceptibility gene 1 and 2 mutant BCs. This review evaluates the activity of emerging targeted agents in TNBC.

DESIGN

A systematic review of PubMed and conference databases was carried out to identify randomised clinical trials reporting outcomes in women with TNBC treated with targeted and platinum-based therapies.

RESULTS AND DISCUSSION

Our review identified TNBC studies of agents with different mechanisms of action, including induction of synthetic lethality and inhibition of angiogenesis, growth, and survival pathways. Combining targeted agents with chemotherapy in TNBC produced only modest gains in progression-free survival, and had little impact on survival. Six TNBC subgroups have been identified and found to differentially respond to specific targeted agents. The use of biological preselection to guide therapy will improve therapeutic indices in target-bearing populations.

CONCLUSION

Ongoing clinical trials of targeted agents in unselected TNBC populations have yet to produce substantial improvements in outcomes, and advancements will depend on their development in target-selected populations.

P4-09-26: Prognostic Significance of Tissue Inhibitor of Metalloproteinase-1 (TIMP-1) in Breast Cancer

Background: Despite advances of systemic treatment in breast cancer guided by hormonal status and HER2 amplification, new prognostic and predictive factors are still warranted to optimize treatments among these patients. Tissue Inhibitor of Metalloproteinase-1 (TIMP-1), a physiologic inhibitor of Matrix Metalloproteinases (MMPs), can act in both pro- and anti-tumoral effects. The prognostic significance of TIMP-1 in breast cancer is still controversial. This study aims to determine the prognostic significance of TIMP-1 in breast cancer. Material and Methods: One-hundred and seventy-six primary breast cancers from women with early stage disease treated with standard adjuvant therapy were analyzed by gene expression microarrays and immunohistochemistry for TIMP-1. Immunohistochemical analysis was independently reviewed by two pathologists.

Results: At the optimized cut-off point, patients with high TIMP-1 RNA levels had a significantly shorter time to relapse, with a hazard ratio (HR) of 1.6 (p = 0.039), but without significant differences in overall survival (HR 1.29, p = 0.37). Although cytoplasmic overexpression of TIMP-1 protein was not correlated with early relapse (HR 1.2, p = 0.35), high expression was associated with shorter overall survival (HR 1.73, p = 0.027). In multivariate analysis, when considering stage, histologic grade, hormonal and HER2 status, TIMP-1 RNA levels remained independently prognostic for early relapse (HR 1.68, p = 0.04).

Discussion: Elevated TIMP-1 RNA levels are independently prognostic for early recurrence, whereas protein overexpression of TIMP-1 is correlated with short overall survival in primary breast cancer.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-09-26.

Human equilibrative nucleoside transporter 1 and carcinoma of the ampulla of Vater: expression differences in tumour histotypes

The human equilibrative nucleoside transporter 1 (hENT1) is the major means by which gemcitabine enters human cells; recent evidence exists that hENT1 is expressed in carcinoma of the ampulla of Vater and that it should be considered as a molecular prognostic marker for patients with resected ampullary cancer. Aim of the present study is to evaluate the variations of hENT1 expression in ampullary carcinomas and to correlate such variations with histological subtypes and clinicopathological parameters. Forty-one ampullary carcinomas were histologically classified into intestinal, pancreaticobiliary and unusual types. hENT1 and Ki67 expression were evaluated by immunohistochemistry, and apoptotic cells were identified by the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate biotin nick end labelling (TUNEL) method. hENT1 overexpression was detected in 63.4% ampullary carcinomas. A significant difference in terms of hENT1 and Ki67 expression was found between intestinal vs. pancreaticobiliary types (P=0.03 and P=0.009 respectively). Moreover, a significant statistical positive correlation was found between apoptotic and proliferative Index (P=0.036), while no significant correlation was found between hENT1 and apoptosis. Our results on hENT1 expression suggest that classification of ampullary carcinoma by morphological subtypes may represent an additional tool in prospective clinical trials aimed at examining treatment efficacy; in addition, data obtained from Ki67 and TUNEL suggest a key role of hENT1 in tumour growth of ampullary carcinoma.

Dichloroacetate (DCA) as a potential metabolic-targeting therapy for cancer

The unique metabolism of most solid tumours (aerobic glycolysis, i.e., Warburg effect) is not only the basis of diagnosing cancer with metabolic imaging but might also be associated with the resistance to apoptosis that characterises cancer. The glycolytic phenotype in cancer appears to be the common denominator of diverse molecular abnormalities in cancer and may be associated with a (potentially reversible) suppression of mitochondrial function. The generic drug dichloroacetate is an orally available small molecule that, by inhibiting the pyruvate dehydrogenase kinase, increases the flux of pyruvate into the mitochondria, promoting glucose oxidation over glycolysis. This reverses the suppressed mitochondrial apoptosis in cancer and results in suppression of tumour growth in vitro and in vivo. Here, we review the scientific and clinical rationale supporting the rapid translation of this promising metabolic modulator in early-phase cancer clinical trials.

Human equilibrative nucleoside transporter 1 (hENT1) protein is associated with short survival in resected ampullary cancer

BACKGROUND

Gemcitabine is an acceptable alternative to best supportive care in the treatment of advanced biliary tract cancers. The human equilibrative nucleoside transporter 1 (hENT1) is a ubiquitous protein and is the major means by which gemcitabine enters human cells. Moreover, recent reports indicate a significant correlation between immunohistochemical variations of hENT1 in tumor samples and survival after gemcitabine therapy in patients with solid tumors.

MATERIALS AND METHODS

We used immunohistochemistry to assess the abundance and distribution of hENT1 in tumor samples from radically resected cancer of the ampulla, and sought correlations between immunohistochemical results and clinical parameters including disease outcomes.

RESULTS

In the 41 individual tumors studied, 12 (29.3%) had uniformly high hENT1 immunostaining. Statistical analysis showed a significant correlation between hENT1 and Ki-67 (P = 0.04). No statistical significant differences were found between immunohistochemical findings and patient characteristics (sex, age, and tumor-node-metastasis). On univariate analysis, hENT1 and Ki-67 expression were associated with overall survival (OS). Specifically, those patients with overexpression of hENT1 showed a shorter OS (P = 0.022) and those with high Ki-67 staining showed a shorter survival (P = 0.05).

CONCLUSIONS

hENT1 expression is a molecular prognostic marker for patients with resected ampullary cancer and holds promise as a predictive factor to assist in chemotherapy decisions.

Nucleoside transport and its significance for anticancer drug resistance

This article discusses the role of nucleoside transport processes in the cytotoxicity of clinically important anticancer nucleosides. This article summarizes recent advances in the molecular biology of nucleoside transport proteins, review the current state of knowledge of the transportability of therapeutically useful anticancer nucleosides, and provide an overview of the role of nucleoside transport deficiency as a mechanism of resistance to nucleoside cytotoxicity are summarized. Several strategies for utilization of nucleoside transport processes to improve the therapeutic index of anticancer therapies, including the use of nucleoside-transport inhibitors to modulate toxicity of both nucleoside and non-nucleoside antimetabolite drugs are also presented.

Mechanisms of uptake and resistance to troxacitabine, a novel deoxycytidine nucleoside analogue, in human leukemic and solid tumor cell lines

Troxacitabine (Troxatyl; BCH-4556; (-)-2'-deoxy-3'-oxacytidine), a deoxycytidine analogue with an unusual dioxolane structure and nonnatural L-configuration, has potent antitumor activity in animal models and is in clinical trials against human malignancies. The current work was undertaken to identify potential biochemical mechanisms of resistance to troxacitabine and to determine whether there are differences in resistance mechanisms between troxacitabine, gemcitabine, and cytarabine in human leukemic and solid tumor cell lines. The CCRF-CEM leukemia cell line was highly sensitive to the antiproliferative effects of troxacitabine, gemcitabine, and cytarabine with inhibition of proliferation by 50% observed at 160, 20, and 10 nM, respectively, whereas a deoxycytidine kinase (dCK)-deficient variant (CEM/dCK(-)) was resistant to all three drugs. In contrast, a nucleoside transport-deficient variant (CEM/ARAC8C) exhibited high levels of resistance to cytarabine (1150-fold) and gemcitabine (432-fold) but only minimal resistance to troxacitabine (7-fold). Analysis of troxacitabine transportability by the five molecularly characterized human nucleoside transporters [human equilibrative nucleoside transporters 1 and 2, human concentrative nucleoside transporter (hCNT) 1, hCNT2, and hCNT3] revealed that short- and long-term uptake of 10-30 microM [(3)H]troxacitabine was low and unaffected by the presence of either nucleoside transport inhibitors or high concentrations of nonradioactive troxacitabine. These results, which suggested that the major route of cellular uptake of troxacitabine was passive diffusion, demonstrated that deficiencies in nucleoside transport were unlikely to impart resistance to troxacitabine. A troxacitabine-resistant prostate cancer subline (DU145(R); 6300-fold) that exhibited reduced uptake of troxacitabine was cross-resistant to both gemcitabine (350-fold) and cytarabine (300-fold). dCK activity toward deoxycytidine in DU145(R) cell lysates was <20% of that in DU145 cell lysates, and no activity was detected toward troxacitabine. Sequence analysis of cDNAs encoding dCK revealed a mutation of a highly conserved amino acid (Trp(92)-->Leu) in DU145(R) dCK, providing a possible explanation for the reduced phosphorylation of troxacitabine in DU145(R) lysates. Reduced deamination of deoxycytidine was also observed in DU145(R) relative to DU145 cells, and this may have contributed to the overall resistance phenotype. These results, which demonstrated a different resistance profile for troxacitabine, gemcitabine, and cytarabine, suggest that troxacitabine may have an advantage over gemcitabine and cytarabine in human malignancies that lack or have low nucleoside transport activities.

Expression of high Km 5'-nucleotidase in leukemic blasts is an independent prognostic factor in adults with acute myeloid leukemia

Cytarabine (ara-C) requires activation into its triphosphorylated form, ara-CTP, to exert cytotoxic activity. Cytoplasmic 5'-nucleotidase (5NT) dephosphorylates ara-CMP, a key intermediate, preventing accumulation of ara-CTP and may reduce cellular sensitivity to the cytotoxic activity of ara-C. To determine whether the level of expression of 5NT is correlated with clinical outcome in patients with acute myeloid leukemia (AML) treated with ara-C, this study analyzed the levels of messenger RNA expression of high Km 5NT by real-time polymerase chain reaction at diagnosis in blast cells of 108 patients with AML. High Km 5NT was expressed at diagnosis in the blast cells of 54% of patients. In univariate analysis, (1) patients whose blast cells contained high levels (values greater than the median value for total population) of high Km 5NT at diagnosis had significantly shorter disease-free survival (DFS) than patients with low levels of high Km 5NT (11 months versus 17.5 months, P =.02) and (2) high levels of high Km 5NT also predicted significantly shorter overall survival (15.7 months versus 39 months, P = .01) in young patients (< or = 57 years; median value for the entire population). In a multivariate analysis taking into account age, karyotype risk, and other factors found to have prognostic significance in univariate analysis, (1) high Km 5NT expression was an independent prognostic factor for DFS and (2) high levels of high Km 5NT also predicted significantly shorter overall survival in young patients. These results demonstrate that the expression of high levels of high Km 5NT in blast cells is correlated with outcome in patients with AML.

Biomonitoring of urinary tamoxifen and its metabolites from breast cancer patients using nonaqueous capillary electrophoresis with electrospray mass spectrometry

Tamoxifen is an antiestrogen drug used to treat breast cancer. We have extracted tamoxifen and several of its metabolites from urine of patients with both metastatic (stage IV) and locally confined (stages I, II, and III) breast cancer. Analysis of these metabolites was performed by nonaqueous capillary electrophoresis with electrospray-mass spectrometry. Peak heights from extracted ion current electropherograms of the metabolites were used to establish a metabolic profile for each patient. We demonstrate substantial variation among patient profiles, statistically significant differences in the amount of urinary tamoxifen N-oxide found in stages I, II, and III compared to stage IV breast cancer patients, and statistically significant differences in the amount of 3,4-dihydroxytamoxifen found in progressors compared to nonprogressors with metastatic (stage IV) cancer.

Nucleoside analogues: mechanisms of drug resistance and reversal strategies

Nucleoside analogues (NA) are essential components of AML induction therapy (cytosine arabinoside), effective treatments of lymphoproliferative disorders (fludarabine, cladribine) and are also used in the treatment of some solid tumors (gemcitabine). These important compounds share some general common characteristics, namely in terms of requiring transport by specific membrane transporters, metabolism and interaction with intracellular targets. However, these compounds differ in regard to the types of transporters that most efficiently transport a given compound, and their preferential interaction with certain targets which may explain why some compounds are more effective against rapidly proliferating tumors and others on neoplasia with a more protracted evolution. In this review, we analyze the available data concerning mechanisms of action of and resistance to NA, with particular emphasis on recent advances in the characterization of nucleoside transporters and on the potential role of activating or inactivating enzymes in the induction of clinical resistance to these compounds. We performed an extensive search of published in vitro and clinical data in which the levels of expression of nucleoside-activating or inactivating enzymes have been correlated with tumor response or patient outcome. Strategies aiming to increase the intracellular concentrations of active compounds are presented.

Intraoperative saline and gemcitabine irrigation improves tumour control in human squamous cell carcinoma-contaminated surgical wounds

INTRODUCTION AND OBJECTIVES

The cure rates for advanced head and neck cancer patients have not changed substantially in the past few decades. Most disease recurrences are local or regional and are likely due to residual microscopic disease or intraoperative wound contamination. We developed a murine model of wound implantation with microscopic disease to assess the efficiency of tumour development and used this model to evaluate the effects on tumour development of surgical bed irrigation with three different solutions.

METHODS

Nonobese diabetic/severe combined immunodeficient mice were transplanted with the University of Michigan squamous cell carcinoma-22B cells derived from a human squamous cell carcinoma of the hypopharynx. Two 1-cm surgical wounds were created on the backs of 20 mice and then instilled with a known quantity of tumour cells. The minimum necessary dose to reliably result in tumour growth was then determined. Forty mice were then inoculated with this minimum tumour concentration. Ten of these mice had their incisions closed immediately and were kept as controls. Ten of the mice had their wounds irrigated with 5 cc of water and then closed, 10 had their wounds irrigated with 5 cc of saline and then closed, and 10 had their wounds irrigated with 5 cc of 1-mM gemcitabine, a nonirritating chemotherapy drug with activity in human head and neck cancers. The mice were then observed for the development of palpable tumours.

RESULTS

We were unable to successfully grow tumours in any wounds that were seeded with less than 2.5 x 10(6) cells. After exposure to 2.5 x 10(6) cells, seven of eight surgical beds developed palpable tumours. This was then taken as our standard inoculation dose. All of the study mice wounds healed rapidly irrespective of irrigation solution. At postoperative day 17, 70% of the controls had evident tumour growth, whereas only 15% of the water irrigation group (p < .0005), 0% of the saline irrigation group (p < .0001), and 0% (p < .0001) of the gemcitabine irrigation group had developed tumours. By day 24, the disease recurrence rates in the water irrigation group no longer differed from controls, whereas the lower incidence of tumour recurrence in the gemcitabine and saline irrigation groups persisted. On day 56, 80% of the control mice and 75% of the water-irrigated mice group had developed palpable tumours. In the saline and gemcitabine groups, however, only 40% (p < .01) and 35% (p < .004), respectively, had evident tumours.

CONCLUSIONS

In a xenograft model of tumour-cell wound contamination, irrigation with saline, water, or gemcitabine delayed tumour development. Irrigation with gemcitabine or saline improved rates of long-term disease control. Gemcitabine irrigation did not affect wound healing and was free of local complications.

The cancer patient with chronic pain due to herpes zoster

Postherpetic neuralgia (PHN) is the most common complication of herpes zoster, and as such has been an area of extensive medical research for the past three decades. The patients at highest risk for PHN include those older than 50 years, those with severe acute cases of zoster, and those with shingles in a trigeminal distribution. As persons with malignancy are at a high risk for developing zoster itself, PHN is a complication that will be faced by many of these patients and their caregivers. This article reviews the available treatments and preventative measures for this debilitating condition.

Phase II study of docetaxel, doxorubicin, and cyclophosphamide as first-line chemotherapy for metastatic breast cancer

PURPOSE

This pilot phase II study investigated the efficacy and toxicity of docetaxel with doxorubicin and cyclophosphamide (TAC) as first-line chemotherapy for anthracycline-naive patients with metastatic breast cancer.

PATIENTS AND METHODS

Fifty-four patients received a total of 359 courses consisting of docetaxel 75 mg/m2 given intravenously (IV) over 1 hour, preceded by IV doxorubicin 50 mg/m2 and cyclophosphamide 500 mg/m2 for a maximum of eight 3-week cycles.

RESULTS

After an independent panel review, the overall objective response rate was 77% (complete response, 6%). Overall objective response rates in patients with visceral, bone, and liver involvement were 82%, 82%, and 80%, respectively. Median duration of response was 52 weeks, and median time to progression was 42 weeks. With a median follow-up of 32 months, the median survival had not yet been reached, whereas the 2-year survival was 57%. The main toxicities were hematologic (neutropenia grade 3/4 in 100% of patients and 95% of cycles; febrile neutropenia in 34% of patients and 9% of cycles). Documented grade 3 infection was seen in one patient (2%) in one cycle, and no toxic death was reported. Severe acute or chronic nonhematologic adverse events were infrequent, and docetaxel-specific toxicities (such as fluid retention and nail changes) were mild, with only one patient being discontinued for fluid retention. Congestive heart failure was seen in two patients (4%).

CONCLUSION

TAC is an active and manageable regimen that has been chosen as the basis of five randomized phase III trials, including two pivotal studies comparing TAC to fluorouracil plus doxorubicin and cyclophosphamide in the metastatic and adjuvant treatment of breast cancer.

Internet usage among women with breast cancer: an exploratory study

An increasing number of breast cancer patients are accessing the Internet for medical information. A survey was administered to breast cancer patients and their families attending follow-up outpatient clinics in a comprehensive cancer care center to explore their frequency of Internet use, their motivation for online activity, the type of information they sought, and the perceived impact of the information they found on the Internet on their medical care. The survey was conducted over a 4-month period. A total of 107 surveys were returned. Seventy-nine of these (74%) were from patients while 28 (26%) were from family members and friends. Thirty-four of the patient responses (43%) indicated that the patient had used the Internet to look for cancer-related information. Patients who had used the Internet to access cancer-related information were significantly younger (P = 0.007), better educated (P = 0.027), and less satisfied with the amount of treatment-related information given by caregivers than those patients who had not used the Internet to access cancer-related information (P = 0.032). The majority of patient Internet users desired more information on their cancer and its treatment (91%), looked up information that was presented to them by their clinicians (66%), researched other treatment options (63%), and obtained more information on "alternative treatments" (63%). Patient Internet users generally found the cancer-related information on the Internet to be useful, and the majority discussed Internet-derived information with their health care providers and perceived that clinicians listened to such information. However, 53% were undecided about the trustworthiness of the medical information obtained via the Internet. Internet nonusers commonly lacked Internet access (53%) or were unfamiliar with the Internet (33%), but few (13%) distrusted Internet-derived information. This exploratory study underscores the need for more research in this area, specifically with the aims of identifying and verifying factors that lead patients to use the Internet and the impact of their online activities on their medical care.

Coping with cancer: can exercise help?

A comprehensive review of the recent literature reveals that exercise has a positive effect on a broad range of quality-of-life parameters after patients are diagnosed as having cancer. The general exercise prescription is moderate-intensity exercise, 3 to 5 days per week, 20 to 30 minutes per session. Conditions that warrant prescription modification include fatigue periods during treatment, acute or chronic physical impairments that may have resulted from surgery or adjuvant therapy, and the presence of bone cancer. Research suggests that physicians who prescribe exercise improve motivation and adherence in their patients who have cancer.

A phase II trial of triamcinolone hexacetanide for symptomatic recurrent malignant ascites

Ascites is a common complication of advanced cancer and frequently requires paracentesis to reduce symptoms of pain, anorexia, and dyspnea. For many patients repeat paracenteses are required at short intervals. We prospectively studied 15 patients with recurrent ascites of malignancy to determine if intraperitoneal triamcinolone hexacetonide, a slowly metabolized corticosteroid, produced objective and symptomatic responses. After biochemical, radiological, and symptom assessment and the establishment of the interval between paracenteses, patients underwent large-volume paracentesis followed by intraperitoneal triamcinolone hexacetonide 10 mg/kg. Patients were followed after treatment for assessment of symptoms and physical signs of ascites. Repeat paracentesis was performed when symptomatic ascites recurred. Symptomatic ascites recurred in 13 of 15 patients, but the interval between paracenteses was extended from 9.5 +/- 1.6 days to 17.5 days (P = 0.0086). Symptom questionnaire scores assessing well-being, nausea, abdominal pain, dyspnea, appetite, appearance, and change in abdominal size on a scale from 0 to 6 averaged 3.2 +/- 0.3 at entry and 2.5 +/- 0.2 at the 2-week assessment (P = 0.026). Self-assessed symptoms, feeling of well-being, abdominal distention, and physical appearance improved significantly. The mean serum cortisol decreased from baseline, suggesting that some systemic corticosteroid absorption occurred. Thirteen of 15 patients have died, with a median survival of 42 days. Potential adverse effects included 1 episode each of transient abdominal pain, bacterial peritonitis, and localized herpes zoster infection. In patients with ascites of malignancy, intraperitoneal triamcinolone hexacetonide appears to postpone the requirement for repeat paracentesis and improve symptoms of malignant ascites.

Differential transport of cytosine-containing nucleosides by recombinant human concentrative nucleoside transporter protein hCNT1

The transportability of cytosine-containing nucleosides by recombinant hCNT1 was investigated in transfected mammalian cells. Apparent K(m) values for hCNT1-mediated transport of uridine, cytidine and deoxycytidine were, respectively, 59, 140 and 150 microM. Uridine transport was inhibited 89, 32 and 11%, respectively, by 500 microM gemcitabine, cytarabine and lamivudine, demonstrating that, unlike gemcitabine (a high-affinity hCNT1 permeant), cytarabine and lamivudine are poor hCNT1 permeants.

Gemcitabine transport in xenopus oocytes expressing recombinant plasma membrane mammalian nucleoside transporters

BACKGROUND

Gemcitabine, a pyrimidine analogue of deoxycytidine, is an anticancer nucleoside drug that requires functional plasma membrane nucleoside transporter proteins to reach its intracellular targets and cause cytotoxicity. Because of technical difficulties inherent in studying nucleoside transport in human cells, we rigorously defined gemcitabine membrane transportability by producing each of the available human (h) and rat (r) recombinant nucleoside transporters (NTs) individually in Xenopus laevis oocytes.

METHODS

Oocytes were microinjected with in vitro-transcribed RNAs derived from complementary DNAs encoding (C = concentrative) rCNT1, rCNT2, hCNT1, hCNT2, (E = equilibrative) rENT1, rENT2, hENT1, and hENT2. Uptake of [(3)H]gemcitabine and [(14)C] uridine was measured 3 days after microinjection to determine kinetic constants. We also used the two-electrode, voltage-clamp technique to investigate the electrophysiology of hCNT1-mediated gemcitabine transport.

RESULTS

Gemcitabine was transported by most of the tested proteins (the exceptions being the purine-selective rCNT2 and hCNT2), with the greatest uptake occurring in oocytes producing recombinant rCNT1 and hCNT1. Influxes of gemcitabine mediated by hCNT1, hENT1, and hENT2 were saturable and conformed to Michaelis-Menten kinetics with apparent K(m) values of 24, 160, and 740 microM, respectively. Gemcitabine had a limited ability to cross the lipid bilayer of oocyte membranes by simple diffusion. External application of gemcitabine to oocytes producing recombinant hCNT1 induced an inward current, which demonstrated that hCNT1 functions as a Na(+)/nucleoside co-transport protein and confirmed the transporter's ability to transport gemcitabine.

CONCLUSIONS

Mammalian nucleoside transporters vary widely in their affinity and capacity to transport gemcitabine. Variation in the tumor and tissue distribution of plasma membrane nucleoside transporter proteins may contribute to the solid tumor activities and schedule-dependent toxic effects of gemcitabine.

Nucleoside transporters: molecular biology and implications for therapeutic development

The uptake of nucleosides (or nucleobases) is essential for nucleic acid synthesis in many human cell types and in parasitic organisms that cannot synthesize nucleotides de novo. The transporters responsible are also the route of entry for many cytotoxic nucleoside analogues used in cancer and viral chemotherapy. Moreover, by regulating adenosine concentrations in the vicinity of its cell-surface receptors, nucleoside transporters profoundly affect neurotransmission, vascular tone and other processes. The recent molecular characterization of two families of human nucleoside transporters has provided new insights into the mechanisms of natural nucleoside and drug uptake and into future developments of improved therapies.

Nucleoside transporters of mammalian cells

In this review, we have summarized recent advances in our understanding of the biology of nucleoside transport arising from new insights provided by the isolation and functional expression of cDNAs encoding the major nucleoside transporters of mammalian cells. Nucleoside transporters are required for permeation of nucleosides across biological membranes and are present in the plasma membranes of most cell types. There is growing evidence that functional nucleoside transporters are required for translocation of nucleosides between intracellular compartments and thus are also present in organellar membranes. Functional studies during the 1980s established that nucleoside transport in mammalian cells occurs by two mechanistically distinct processes, facilitated diffusion and Na(+)-nucleoside cotransport. The determination of the primary amino acid sequences of the equilibrative and concentrative transporters of human and rat cells has provided a structural basis for the functional differences among the different transporter subtypes. Although nucleoside transporter proteins were first purified from human erythrocytes a decade ago, the low abundance of nucleoside transporter proteins in membranes of mammalian cells has hindered analysis of relationships between transporter structure and function. The molecular cloning of cDNAs encoding nucleoside transporters and the development of heterologous expression systems for production of recombinant nucleoside transporters, when combined with recombinant DNA technologies, provide powerful tools for characterization of functional domains within transporter proteins that are involved in nucleoside recognition and translocation. As relationships between molecular structure and function are determined, it should be possible to develop new approaches for optimizing the transportability of nucleoside drugs into diseased tissues, for development of new transport inhibitors, including reagents that are targeted to the concentrative transporters, and, eventually, for manipulation of transporter function through an understanding of the regulation of transport activity.

Functional nucleoside transporters are required for gemcitabine influx and manifestation of toxicity in cancer cell lines

Gemcitabine (2',2'-difluorodeoxycytidine) is a novel pyrimidine nucleoside drug with clinical efficacy in several common epithelial cancers. We have proposed that gemcitabine requires nucleoside transporter (NT) proteins to permeate the plasma membrane and to exhibit pharmacological activity. In humans, there are seven reported distinct NT activities varying in substrate specificity, sodium dependence, and sensitivity to inhibition by nitrobenzylthioinosine (NBMPR) and dipyridamole. To determine which NTs are required for gemcitabine-dependent growth inhibition, cultures from a panel of 12 cell lines with defined plasma membrane NT activities were incubated with different concentrations of gemcitabine. Cell proliferation was assessed by the sulforhodamine B assay and cell enumeration to identify the concentrations of gemcitabine that inhibited cell replication by 50% (IC50s). NT activity was a prerequisite for growth inhibition in vitro because: (a) the nucleoside transport-deficient cells were highly resistant to gemcitabine; and (b) treatment of cells that exhibited only equilibrative NT activity with NBMPR or dipyridamole increased resistance to gemcitabine by 39- to 1800-fold. These data suggested that the type of NT activities possessed by a cell may be an important determinant of its sensitivity to gemcitabine and that NT deficiency may confer significant gemcitabine resistance. We analyzed the uptake kinetics of [3H]gemcitabine by each of five human NT activities in cell lines that exhibited a single NT activity in isolation; transient transfection of the cDNAs encoding the human concentrative NT proteins (hCNT1 and hCNT2) was used to study the cit and cif activities, respectively. The efficiency of gemcitabine uptake varied markedly among the cell lines with single NTs: es approximately = cit > ei > cib >>> cif. The transportability of [3H]gemcitabine was demonstrated by reconstitution of the human es NT in proteoliposomes, confirming that gemcitabine permeation is a protein-mediated process.

Molecular cloning, functional expression and chromosomal localization of a cDNA encoding a human Na+/nucleoside cotransporter (hCNT2) selective for purine nucleosides and uridine

Two Na(+)-dependent nucleoside transporters implicated in adenosine and uridine transport in mammalian cells are distinguished functionally on the basis of substrate specificity: CNT1 is selective for pyrimidine nucleosides but also transports adenosine; CNT2 (also termed SPNT) is selective for purine nucleosides but also transports uridine. Both proteins belong to a gene family that includes the NupC proton/nucleoside symporter of E. coli. cDNAs encoding members of the CNT family have been isolated from rat tissues (jejunum, brain, liver; rCNT1 and rCNT2/SPNT) and, most recently, human kidney (hCNT1 and hSPNT1). Here, the molecular cloning and functional characterization of a CNT2/SPNT-type transporter from human small intestine are described. The encoded 658-residue protein (hCNT2 in the nomenclature) had the same predicted amino acid sequence as human kidney hSPNT1, except for a polymorphism at residue 75 (Arg substituted by Ser), and was 83 and 72% identical to rCNT2 and hCNT1, respectively. Sequence differences between hCNT2 and rCNT2 were greatest at the N-terminus. In Xenopus oocytes, recombinant hCNT2 exhibited the functional characteristics of a Na(+)-dependent nucleoside transporter with selectivity for adenosine, other purine nucleosides and uridine (adenosine and uridine K(m) app values 8 and 40 microM, respectively). hCNT2 transcripts were found in kidney and small intestine but, unlike rCNT2, were not detected in liver. Deoxyadenosine, which undergoes net renal secretion in humans, was less readily transported than adenosine. hCNT2 also mediated small, but significant, fluxes of the antiviral purine nucleoside analogue 2',3'-dideoxyinosine. hCNT2 is, therefore potentially involved in both the intestinal absorption and renal handling of purine nucleosides (including adenosine), uridine and purine nucleoside drugs. The gene encoding hCNT2 was mapped to chromosome 15q15.