Abstract 4040: MicroRNAs that chemosensitize the apoptotic effect of 17-AAG

Abstract Background: 17-allylamino-demethoxy geldanamycin (17-AAG) inhibits the chaperone function of heat shock protein 90 (Hsp90) and promotes the proteasomal degradation of its client proteins. 17AAG also induced the mitochondrial release, accumulation of mitochondrial-derived activator of caspases, resulting in apoptosis. 17-AAG is currently in development for the treatment of cancer. MicroRNAs (miRNAs) are small, noncoding RNAs that regulate expression of many genes and play a significant role in cancer and possibly in Hsp90 signaling. Therefore, a screen of miRNA mimics and inhibitors was conducted for chemosensitization to 17-AAG. Methods: To identify individual microRNAs that synergizes with 17AAG, microRNA libraries were screened for apoptotic activity against HT29 cells when co-treated with 17AAG. The microRNAs were transfected into HT29 cells 48 hrs before treatment with 17AAG. After 72 hrs of 17AAG exposure, apoptosis was quantitated by the release of caspase 3/7. The effects of these miRNA on cellular protein, mRNA, and miRNA profile were also examined using microarray technology. Results: Four miRNAs were identified which had potent chemosensitization effect on cells exposed to 17-AAG. These miRNA are different in sequence and did not synergize with one another. Alone they did not induce apoptosis; however, when combined with 17-AAG, they increased the apoptotic activity of 17-AAG up to 4 folds. Possible mechanism of action for these miRNAs was examined by microarray analysis which suggested that they act on the Hsp90/70 pathway to enhance the activity of 17-AAG. Conclusions: Four miRNAs were identified as chemosensitizers for 17-AAG. These miRNAs could provide the basis for determination of tumor types that will be sensitive to 17-AAG, as well as a potential biomarker for predicting 17-AAG effectiveness. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4040.</jats:p

Changing Landscape of Clinical-Genomic Oncology Practice

&lt;p&gt;The current paper discusses the use of genomics in the context of the changing landscape of clinical practice and modern medicine. Medical practice has shifted considerably over the past few decades, from empirical to evidence-based to personalized medicine, and the transition from reliance on observation to measureable parameters. Scientific innovation is required to collect an ever-increasing number and variety of data points and sophisticated analyses capable of distilling vast datasets into meaningful information. The next phase of innovation seeks to personalize disease management, in particular through genomics in oncology. With expanding use of genomics in medicine, and several initiatives collecting genomic data at the population level, education of patients and physicians is critical for data utility. By combining genomic and clinical data, bioinformatics approaches can be applied to developing individualized or targeted therapies. Breast cancer provides an example through which to understand the evolution of genomic data from purescience to clinical utility. From intrinsic subtype classification to development of multigene panels estimating recurrence risk, new studies, such as the FLEX trial, will expand to evaluate the whole transcriptome of tumours. This approach will enable discovery of novel gene signatures and ultimately pave the way toward a personalized approach to breast cancer management.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion. &lt;/strong&gt;Despite the potential for genomics to personalize treatments, a number of challenges remain to fully integrate these types of large datasets in a manner that provides clinicians and patients with meaningful, actionable information. However, if challenges are addressed, precision medicine has the capacity to transform patient care.&lt;/p&gt;</jats:p

Genomic Impact of Neoadjuvant Therapy on Breast Cancer: Incomplete Response is Associated with Altered Diagnostic Gene Signatures.

PURPOSE: Neoadjuvant therapy (NAT) has been shown to clinically downstage locally advanced breast cancers. This study aimed to determine whether a meaningful change in gene signatures occurs between pre- and post-NAT breast cancers for patients who do not achieve a pathologic complete response. METHODS: The current analysis included women from the prospective Neoadjuvant Breast Registry Symphony Trial who had breast cancer and awaited NAT. MammaPrint and BluePrint (Agendia, Inc., Irvine, CA) assays were performed on pre- and post-NAT breast tumor samples. RESULTS: At the completion of NAT, 93 patients with residual disease had their remaining tumor analyzed for MammaPrint and BluePrint. Of 93 patients, 21 switched tumor classification: 16 from high risk (HR) to low risk (LR) and 1 from LR to HR (p \u3c 0.001). Four additional patients switched molecular subtype but remained HR. Although only 17 patients switched in their MammaPrint risk classification, the underlying MPIndex was significantly altered after treatment across all patients (p \u3c 0.001). Additionally, the three BluePrint indices for luminal, human epidermal growth factor receptor 2 (HER2), and basal type also were significantly altered after treatment, in a subtype-dependent manner. CONCLUSION: This substudy showed that NAT significantly altered the genomic signature of the patient\u27s breast cancer compared with the patient\u27s pretreatment genomic profile. These alterations occurred in a subtype-dependent manner, suggesting that NAT may have either eliminated the most susceptible tumor subclone, leaving the treatment resistant clone with a different genetic signature, or altered molecular characteristics of the original cancer

Race and response to neoadjuvant chemotherapy according to MammaPrint risk.

578 Background: African-American (AA) women with breast cancer have a less favorable prognosis, likely due to differences in tumor biology. This is not only driven by the higher rate of triple negative/basal tumors in patients with AA ancestry, as worse outcome has also been seen in patients with luminal tumors. The Neoadjuvant BReast Cancer Symphony Trial (NBRST, NCT01479101) was a prospective trial that has shown an association of MammaPrint/BluePrint (MP/BP) with a rate of pathologic Complete Response (pCR) of 2% in Luminal A with 95% Distant Metastasis Free Interval at 3 years. Here, we determine the MP/BP risk distribution, response to therapy, and outcome in African American (AA) and Caucasian (Cau) patients. Methods: NBRST enrolled 1,072 breast cancer patients (pts) in the US (June 2011 and December 2014), median follow-up 34.9 months. The current unplanned analysis compared clinicopathological characteristics, molecular risk assignment and outcome with neoadjuvant chemotherapy (NACT) in AA and Cau pts. Molecular subtyping groups were assessed by MP/BP as follows: Luminal A (MammaPrint Low Risk), Luminal B (MammaPrint High Risk), HER2 and Basal types. Results: Out of 1,072 pts, 157 (15%) were AA, and 780 (73%) were Cau. AA patients were younger at diagnosis (52 vs 54 yrs; p = 0.016), had a higher likelihood of having higher grade (gr 3, 65% vs 53%; p = 0.005), ER-negative (45% vs 33%; p = 0.005) and lymph node positive tumors (71% vs 51; p &lt; 0.001). MP/BP classified more AA patients as Basal type, 45% compared to 33% of Cau patients (p = 0.004). Fewer AA patients were classified as Luminal A (15%) compared to Cau pts (33%; p = 0.004). In multivariate analysis race was a significant factor for higher pCR rates to NACT in AA compared to Cau pts, together with PR, HER2, T-stage and Grade (HR = 1.679, 95% CI = (1.057, 2.67), p = 0.028). The pCR rate to NACT in patients with Basal tumors was 38% and similar in AA and Cau patients. In patients with hormone receptor positive and HER2 negative tumors, patients classified by MP/BP as Luminal A had lower pCR (2%) compared to non-luminal A (13%) (p = 0.0015). MP low risk patients had higher 3 yr DMFS (97%) than MP high risk patients (86%; p = 0.010). DMFS for AA MP Low Risk patients was 100%. Conclusions: In this study, MP was able to identify patients with hormone receptor positive tumors with low sensitivity to chemotherapy and good outcome, irrespective of race, suggesting that this test can be helpful to characterize the tumor’s biology and select patients who will not benefit from chemotherapy independently of their ancestry. Clinical trial information: NCT01479101. </jats:p

Estrogen receptor variants in ER-positive basal-type breast cancers responding to therapy like ER-negative breast cancers

AbstractImmunohistochemically ER-positive HER2-negative (ER+HER2−) breast cancers are classified clinically as Luminal-type. We showed previously that molecular subtyping using the 80-gene signature (80-GS) reclassified a subset of ER+HER2− tumors to molecular Basal-type. We report here that molecular reclassification is associated with expression of dominant-negative ER variants and evaluate response to neoadjuvant therapy and outcome in the prospective neoadjuvant NBRST study (NCT01479101). The 80-GS reclassified 91 of 694 (13.1%) immunohistochemically Luminal-type tumors to molecular Basal-type. Importantly, all 91 discordant tumors were classified as high-risk, whereas only 66.9% of ER+/Luminal-type tumors were classified at high-risk for disease recurrence (i.e., Luminal B) (P &lt; 0.001). ER variant mRNA (ER∆3, ER∆7, and ERα-36) analysis performed on 84 ER+/Basal tumors and 48 ER+/Luminal B control tumors revealed that total ER mRNA was significantly lower in ER+/Basal tumors. The relative expression of ER∆7/total ER was significantly higher in ER+/Basal tumors compared to ER+/Luminal B tumors (P &lt; 0.001). ER+/Basal patients had similar pathological complete response (pCR) rates following neoadjuvant chemotherapy as ER−/Basal patients (34.3 vs. 37.6%), and much higher than ER+/Luminal A or B patients (2.3 and 5.8%, respectively). Furthermore, 3-year distant metastasis-free interval (DMFI) for ER+/Basal patients was 65.8%, significantly lower than 96.3 and 88.9% for ER+/Luminal A and B patients, respectively, (log-rank P &lt; 0.001). Significantly lower total ER mRNA and increased relative ER∆7 dominant-negative variant expression provides a rationale why ER+/Basal breast cancers are molecularly ER-negative. Identification of this substantial subset of patients is clinically relevant because of the higher pCR rate to neoadjuvant chemotherapy and correlation with clinical outcome.</jats:p

Association of 70-gene signature assay findings with physicians\u27 treatment guidance for patients with early breast cancer classified as intermediate risk by the 21-gene assay

Importance: Among patients who undergo the 21-gene assay (21-GA), 39% to 67% receive an intermediate risk result and may receive ambiguous treatment guidance. The 70-gene signature assay (70-GS) may be associated with physicians\u27 treatment decisions in this population with early breast cancer. Objective: To determine whether 70-GS findings are associated with physicians\u27 decisions about adjuvant treatment and confidence in their recommendations and to evaluate the dichotomous (high- vs low-risk) and continuous distribution of 70-GS indices among this group of patients with intermediate risk. Design, Setting, and Participants: The Prospective Study of MammaPrint in Breast Cancer Patients With an Intermediate Recurrence Score (PROMIS trial) was an impact study conducted from May 20, 2012, through December 31, 2015, that enrolled 840 patients with early-stage breast cancer and a 21-gene assay recurrence score of 18 to 30. Patients were treated in 58 US institutions. Interventions: The 70-GS result was given to physicians before adjuvant treatment. Main Outcomes and Measures: Change in physician treatment decision before vs after receiving the 70-GS result. With a treatment change of greater than 20%, the odds ratio (OR) was applied. Results: Among the 840 patients who underwent 70-GS classification (mean age, 59 years; range, 27-93 years), 374 (44.5%) had a low-risk and 466 (55.5%) had a high-risk result. The distribution of 70-GS indices did not correlate with recurrence score within the 21-GA intermediate range, with 70-GS low- and high-risk patients observed at every recurrence score. A significant change in adjuvant treatment was associated with receiving the 70-GS classifications with an OR of 0.64 (95% CI, 0.50-0.82; McNemar test, P \u3c .001) for all patients. Among the low-risk patients, 108 of 374 (28.9%) had chemotherapy removed from their treatment recommendation; among the high-risk patients, 171 of 466 (36.7%) had chemotherapy added. Results of the 70-GS were associated with the physician\u27s adjuvant treatment recommendation; 409 high-risk patients (87.8%) were recommended to receive adjuvant chemotherapy, and 339 low-risk patients (90.6%) were recommended no chemotherapy. Physicians reported having greater confidence in their treatment recommendation in 660 cases (78.6%) based on 70-GS results. Conclusions and Relevance: The 70-GS provides clinically actionable information regarding patients classified as intermediate risk by the 21-GA and was associated with a change in treatment decision in 282 of these patients (33.6%). Chemotherapy was added or withheld by the treating physician based on the results of the 70-GS test. Physicians reported more confidence with their treatment recommendation after receiving 70-GS results

MammaPrint guides treatment decisions in breast Cancer: results of the IMPACt trial

Abstract Background Increased usage of genomic risk assessment assays suggests increased reliance on data provided by these assays to guide therapy decisions. The current study aimed to assess the change in treatment decision and physician confidence based on the 70-gene risk of recurrence signature (70-GS, MammaPrint) and the 80-gene molecular subtype signature (80-GS, BluePrint) in early stage breast cancer patients. Methods IMPACt, a prospective, case-only study, enrolled 452 patients between November 2015 and August 2017. The primary objective population included 358 patients with stage I-II, hormone receptor-positive, HER2-negative breast cancer. The recommended treatment plan and physician confidence were captured before and after receiving results for 70-GS and 80-GS. Treatment was started after obtaining results. The distribution of 70-GS High Risk (HR) and Low Risk (LR) patients was evaluated, in addition to the distribution of 80-GS compared to IHC status. Results The 70-GS classified 62.5% (n = 224/358) of patients as LR and 37.5% (n = 134/358) as HR. Treatment decisions were changed for 24.0% (n = 86/358) of patients after receiving 70-GS and 80-GS results. Of the LR patients initially prescribed CT, 71.0% (44/62) had CT removed from their treatment recommendation. Of the HR patients not initially prescribed CT, 65.1% (41/63) had CT added. After receiving 70-GS results, CT was included in 83.6% (n = 112/134) of 70-GS HR patient treatment plans, and 91.5% (n = 205/224) of 70-GS LR patient treatment plans did not include CT. For patients who disagreed with the treatment recommended by their physicians, most (94.1%, n = 16/17) elected not to receive CT when it was recommended. For patients whose physician-recommended treatment plan was discordant with 70-GS results, discordance was significantly associated with age and lymph node status. Conclusions The IMPACt trial showed that treatment plans were 88.5% (n = 317/358) in agreement with 70-GS results, indicating that physicians make treatment decisions in clinical practice based on the 70-GS result. In clinically high risk, 70-GS Low Risk patients, there was a 60.0% reduction in treatment recommendations that include CT. Additionally, physicians reported having greater confidence in treatment decisions for their patients in 72% (n = 258/358) of cases after receiving 70-GS results. Trial registration “Measuring the Impact of MammaPrint on Adjuvant and Neoadjuvant Treatment in Breast Cancer Patients: A Prospective Registry” (NCT02670577) retrospectively registered on Jan 27, 2016. </jats:sec