Prevalence and mutational determinants of high tumor mutation burden in breast cancer

BACKGROUND

High tumor mutation burden (TMB) can benefit immunotherapy for multiple tumor types, but the prevalence of hypermutated breast cancer is not well described. The aim of this study was to evaluate the frequency, mutational patterns, and genomic profile of hypermutated breast cancer.

PATIENTS AND METHODS

We used de-identified data from individuals with primary or metastatic breast cancer from six different publicly available genomic studies. The prevalence of hypermutated breast cancer was determined among 3969 patients' samples that underwent whole exome sequencing or gene panel sequencing. The samples were classified as having high TMB if they had ≥10 mutations per megabase (mut/Mb). An additional eight patients were identified from a Dana-Farber Cancer Institute cohort for inclusion in the hypermutated cohort. Among the patients with high TMB, the mutational patterns and genomic profiles were determined. A subset of patients was treated with regimens containing PD-1 inhibitors.

RESULTS

The median TMB was 2.63 mut/Mb. The median TMB significantly varied according to the tumor subtype (HR-/HER2- >HER2+ >HR+/HER2-, P < 0.05) and sample type (metastatic > primary, P = 2.2 × 10^-16). Hypermutated tumors were found in 198 patients (5%), with enrichment in metastatic versus primary tumors (8.4% versus 2.9%, P = 6.5 × 10^-14). APOBEC activity (59.2%), followed by mismatch repair deficiency (MMRd; 36.4%), were the most common mutational processes among hypermutated tumors. Three patients with hypermutated breast cancer-including two with a dominant APOBEC activity signature and one with a dominant MMRd signature-treated with pembrolizumab-based therapies derived an objective and durable response to therapy.

CONCLUSION

Hypermutation occurs in 5% of all breast cancers with enrichment in metastatic tumors. Different mutational signatures are present in this population with APOBEC activity being the most common dominant process. Preliminary data suggest that hypermutated breast cancers are more likely to benefit from PD-1 inhibitors.

Interleukin-1β Regulates Lipid Homeostasis in Human Glomerular Mesangial Cells

BACKGROUND

Recent studies have shown that hyperlipidemia is closely related to the progression of kidney disease and glomerulosclerosis has similar pathophysiological mechanisms with atherosclerosis. Atherosclerosis is essentially a chronic inflammatory process and various kidney diseases are characterized by a micro-inflammatory state. Hyperlipidemia levels are not parallel to the degree of glomerulosclerosis, inflammatory factors together with lipids may contribute to the pathogenesis of glomerulosclerosis. Therefore, it is key to clarify lipid-mediated renal injury through studying the mechanism by which inflammation affects cholesterol homeostasis at the cellular level. Intracellular lipid homeostasis involves both lipid uptake and excretion, therefore in this study, we aimed to explore whether interleukin-1β (IL-1β) promotes the uptake of oxidized low-density lipoprotein (Ox-LDL) to increase in intracellular lipid levels, and to clarify the effect of IL-1β on the expression of lectin-like oxidized LDL receptor 1 (LOX-1) and ATP-binding cassette transporter A1 (ABCA1), which may regulate cholesterol homeostasis in human mesangial cells (HMCs).

METHODS

The effect of IL-1β on uptake of Ox-LDL labeled with fluorescent Dil (Dil-Ox-LDL) by HMCs was observed using laser confocal microscopy. The effect of IL-1β on LOX-1 and ABCA1 expression in HMCs was detected by polymerase chain reaction and western blotting.

RESULTS

Laser confocal microscopy revealed that HMCs took up Dil-Ox-LDL. Treatment of HMCs with 5 ng/ml IL-1β for 24 h significantly increased uptake of Dil-Ox-LDL. IL-1β also promoted LOX-1 mRNA and protein expression in a dose-dependent manner. Moreover, ABCA1 mRNA and protein expression were reduced by IL-1β in lipid-loaded HMCs in a dose-dependent manner.

CONCLUSIONS

IL-1β promotes the uptake of Ox-LDL and expression of LOX-1 in HMCs, whereas it inhibits expression of ABCA1 under lipid load. The imbalance in intracellular cholesterol resulted by IL-1β can in turn transform HMCs into foam cells and aggravate glomerulosclerosis.

Duration of EEG suppression does not predict recovery time or degree of cognitive impairment after general anaesthesia in human volunteers

BACKGROUND

Burst suppression occurs in the EEG during coma and under general anaesthesia. It has been assumed that burst suppression represents a deeper state of anaesthesia from which it is more difficult to recover. This has not been directly demonstrated, however. Here, we test this hypothesis directly by assessing relationships between EEG suppression in human volunteers and recovery of consciousness.

METHODS

We recorded the EEG of 27 healthy humans (nine women/18 men) anaesthetised with isoflurane 1.3 minimum alveolar concentration (MAC) for 3 h. Periods of EEG suppression and non-suppression were separated using principal component analysis of the spectrogram. After emergence, participants completed the digit symbol substitution test and the psychomotor vigilance test.

RESULTS

Volunteers demonstrated marked variability in multiple features of the suppressed EEG. In order to test the hypothesis that, for an individual subject, inclusion of features of suppression would improve accuracy of a model built to predict time of emergence, two types of models were constructed: one with a suppression-related feature included and one without. Contrary to our hypothesis, Akaike information criterion demonstrated that the addition of a suppression-related feature did not improve the ability of the model to predict time to emergence. Furthermore, the amounts of EEG suppression and decrements in cognitive task performance relative to pre-anaesthesia baseline were not significantly correlated.

CONCLUSIONS

These findings suggest that, in contrast to current assumptions, EEG suppression in and of itself is not an important determinant of recovery time or the degree of cognitive impairment upon emergence from anaesthesia in healthy adults.

DNA methylation signature of smoking in lung cancer is enriched for exposure signatures in newborn and adult blood

Smoking impacts DNA methylation genome-wide in blood of newborns from maternal smoking during pregnancy and adults from personal smoking. We compared smoking-related DNA methylation in lung adenocarcinoma (61 never smokers, 91 current smokers, and 238 former smokers) quantified with the Illumina450k BeadArray in The Cancer Genome Atlas with published large consortium meta-analyses of newborn and adult blood. We assessed whether CpG sites related to smoking in blood from newborns and adults were enriched in the lung adenocarcinoma methylation signal. Testing CpGs differentially methylated by smoke exposure, we identified 296 in lung adenocarcinoma meeting a P < 10-4 cutoff, while previous meta-analyses identified 3,042 in newborn blood, and 8,898 in adult blood meeting the same P < 10-4 cutoff. Lung signals were highly enriched for those seen in newborn (24 overlapping CpGs, Penrichment = 1.2 × 10-18) and adult blood (66 overlapping CpGs, Penrichment = 1.2 × 10-48). The 105 genes annotated to CpGs differentially methylated in lung tumors, but not blood, were enriched for RNA processing ontologies. Some epigenetic alterations associated with cigarette smoke exposure are tissue specific, but others are common across tissues. These findings support the value of blood-based methylation biomarkers for assessing exposure effects in target tissues.

Abstract OT2-07-08: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Paplomata E, Borges V, Loi S, Abramson V, Hamilton E, Hurvitz S, Lin N, Walker L, Murthy RK. Withdrawn [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 OT2-07-08.

Abstract ES3-3: Systemic therapy for breast cancer brain metastases

Brain metastases occur in up to half of patients with HER2-positive metastatic breast cancer, 25-45% of patients with metastatic triple-negative breast cancer, and 10-15% of patients with metastatic ER-positive breast cancer. While local approaches such as surgery and radiotherapy can be effective, they do not address extracranial disease, and can be associated with short- and long-term toxicity. As some subsets of patients live longer after a diagnosis of brain metastasis, there is increasing interest in systemic approaches in lieu of repetitive rounds of local therapy. To date, no systemic therapy has gained an indication for the specific treatment of breast cancer brain metastases; however, a number of regimens have been associated with efficacy in the central nervous system (CNS) in non-randomized studies. For patients with HER2-positive breast cancer, the combination of lapatinib and capecitabine has been associated with CNS response rates of 66% in the upfront setting, and 18-38% in patients whose disease has progressed after prior radiotherapy. Several investigational HER2-targeted tyrosine kinase inhibitors have shown promise. The combination of tucatinib, capecitabine and trastuzumab was associated with a CNS response rate of 42% in a small number of patients with brain metastases treated on the phase 1 trial. Notably, patients with brain metastases (either stable or progressive) are allowed on the current tucatinib registration trial (NCT02614794). The combination of neratinib and capecitabine led to a CNS response rate = 49% in a prospective phase 2 trial. Finally, trastuzumab-emtansine has been reported to lead to CNS regressions in up to 40% of patients, based upon case series from several institutions.

For patients with ER-positive breast cancer, endocrine therapies such as tamoxifen and aromatase inhibitors have been reported to induce CNS responses in case reports and small case series. Recently, there has been interest in exploring the role of CDK4/6 inhibitors in patients with brain metastases. Preliminary results of the JPBO study support potential CNS efficacy of abemaciclib in patients with ER+ breast cancer; final results are awaited. To date, no commercially available targeted agents have demonstrated efficacy against brain metastases from triple-negative breast cancer. Trials of immunotherapy approaches in breast cancer have almost completely excluded patients with active/progressive brain metastases and thus, the safety/efficacy profile of immunotherapy in this setting is unknown, though promising data in melanoma and lung cancer would support its exploration in patients with brain metastases from breast cancer.

Despite the fact that most chemotherapeutic agents do not cross the intact blood brain barrier, it appears empirically that the blood-tumor barrier can be sufficiently disrupted to allow for CNS efficacy in the case of established brain metastases. Diverse agents including anthracyclines, capecitabine, platinum salts, and irinotecan have been reported to be associated with CNS response in breast cancer patients. Newer compounds which have been engineered to improve upon CNS penetration and/or CNS residence time are in clinical development and testing.

Citation Format: Lin N. Systemic therapy for breast cancer brain metastases [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 ES3-3.

Abstract P1-09-15: DNA methylation markers influenced by BMI are associated with breast cancer

Body mass index (BMI) is a well-established risk factor for breast cancer. However, the underlying molecular mechanism through which BMI acts on breast cancer remain largely unknown. DNA methylation plays a critical role in regulating gene expression. Aberrant DNA methylation has been implicated in breast cancer development. We hypothesize that BMI influences DNA methylation that in turn leads to breast cancer. We therefore conducted a molecular epidemiological study to identify DNA methylation markers that are associated with BMI in healthy women and further determine the association of these DNA methylation changes with breast cancer development and occurrence. We analyzed 270 normal breast tissue from healthy women and 109 tumor tissue from breast cancer patients for genome-wide DNA methylation profiling using the Illumina Truseq® Methyl Capture EPIC sequencing technology. After data quality control, approximately 3 million CpG sites (sequencing depth≥10) were retained and included in further statistical analysis. Linear regression was performed to examine the association between BMI and each of CpG sites, adjusting for age and race. Bonferroni correction was used for control for multiple comparisons. We further investigated whether these BMI-associated DNA methylation markers were differentially methylated in normal and breast tissue. We found that 30 CpG sites were significantly associated with BMI (P&lt; 1.5x 10-8) in normal breast tissue. Many of these GpG sites were also differentially methylated in tumor and normal breast tissue. Top CpG hits are near novel and putative cancer genes mainly involved in lipid metabolism and related reproductive phenotypes that increase breast cancer risk, including KIAA0232, SHZ2, LACTB, PAPPA, and DLGAP2. The most significant CpG site associated with BMI is on chr. 4 in KIAA0232 gene. Little is known about the function of this gene, but genetic variant near the gene are associated with platelet count and volume in GWAS. The second most significant hit is on chr.20 in gene TSHZ2. This gene is found downregulated in breast and prostate cancer. LACTB gene is a tumor suppressor that modulates lipid metabolism and cell state. Its mechanism of action involves alteration of mitochondrial lipid metabolism and differentiation of breast cancer cells. PAPPA gene plays a role in inflammation and promote invasion of cancer cells. DLGAP2 is an imprinted gene, and SNPs near DLGAP2 are associated with age at menarche in AA women. Our results suggest DNA methylation may intermediate the observed association between BMI and breast cancer. Further research is warranted to validate these findings in larger studies as well as to understand the regulatory network by linking data with gene expression.

Citation Format: He C, Lin N, Castle J, Liu J, Liu Y, Wang C. DNA methylation markers influenced by BMI are associated with breast cancer [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 P1-09-15.

Abstract PD9-02: Evolutionary analysis of 462 serial metastatic biopsies from 208 patients with estrogen receptor-positive (ER+) metastatic breast cancer (MBC) using whole exome sequencing (WES)

Background: While great strides have been made in the treatment of ER+ MBC, therapeutic resistance is nearly universal. The genomic evolution of ER+ breast cancer in the metastatic setting under the selective pressure of multiple lines of therapies is not well understood. To address this, we analyzed the clonal dynamics of serial metastatic samples (mets) to evaluate how tumors evolve and to identify acquired resistance mechanisms.

Methods: We performed WES on 462 clinically annotated samples from 208 patients (pts) with ER+ MBC, including 67 primary tumor biopsies, 229 metastatic biopsies and 160 blood samples (cfDNA). Pts with multiple mets included cases with temporally concordant metastatic tumor and blood samples (48 pts) and cases with serial mets obtained over the course of treatment in the metastatic setting (69 pts). Treatments given between the serial mets included CDK4/6 inhibitors (23 pts), and selective estrogen receptor degraders (19 pts), among others.

Results: In the temporally-concordant mets, we found that cfDNA mutations (muts) largely overlap with muts found in tumor biopsies, capturing &gt;85% of clonal tumor muts. However, we observed a higher level of heterogeneity in cfDNA compared to biopsies (p.value&lt; 1.05e-19, Welch test) and a subset of high-confidence muts that were only detected in cfDNA, including in clinically important genes such as ESR1, PIK3CA, KRAS, and ERBB2. Analysis of serial mets was used to elucidate the evolutionary dynamics within the metastatic setting under the selective pressure of treatment. The median duration between mets was 112 days and the median number of inter-biopsy unique treatments was two. Most tumors continued to evolve within the metastatic setting, with 50 out of 69 pts (72%) acquiring a meaningful sub-clone (50% increase in relative cancer cell fraction) and 31 out of 69 (45%) acquiring muts in known cancer genes, including a subset acquiring a plausible resistance alteration such as alterations that dysregulate ER (5 out of 69 pts, 7%; ESR1 mut, FOXA1 amplification (amp), NCOR1 bi-allelic deletion (del)), ERBB (4%; ERBB2 amp, ERBB3 mut), RAS (4%; KRAS mut, NRAS amp, NF1 del), FGF/FGFR (12%; FGFR2 mut, FGFR1/2 amp, FGF3 amp), and cell cycle (13%; RB1 del, CDK4 amp, AURKA amp, CDKN2A del). Finally, in pts who had multiple mets, we observed several cases of evolutionary convergence toward equivalent resistance mechanisms including convergent RB1 loss as a mechanism of resistance to a CDK4/6 inhibitor and convergent BRCA2 reversion following resistance to a PARP inhibitor.

Conclusions: This study demonstrates that ER+ MBC continues to evolve under the selective pressure of treatments in the metastatic setting. These findings elucidate the challenge of studying high complexity and heavily treated tumors, while also highlighting some commonalities in the evolutionary trajectories selected by these treatments. The multiplicity of clinically relevant genomic alterations acquired in these advanced stages highlights the need for serial biopsies and the potential to inform post-progression therapeutic choices through targeting the acquired dependencies in post-progression tumors.

Citation Format: Cohen O, Buendia-Buendia J, Wander S, Nayar U, Mao P, Waks A, Kim D, Freeman S, Adalsteinsson V, Helvie K, Livitz D, Rosebrock D, Leshchiner I, Dellostritto L, Garrido-Castro A, Jain E, Periyasamy S, Mackichan C, Lloyd M, Marini L, Krop I, Garraway L, Getz G, Winer E, Lin N, Wagle N. Evolutionary analysis of 462 serial metastatic biopsies from 208 patients with estrogen receptor-positive (ER+) metastatic breast cancer (MBC) using whole exome sequencing (WES) [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 PD9-02.

Investigation for the role of CTX-III and microRNA-98 in diagnosis and treatment of osteoarthritis

OBJECTIVE

Osteoarthritis is a joint degeneration and proliferative inflammatory disease caused by obesity, joint deformities, trauma, and other factors. C-terminal collagen (CTX) is associated with cartilage degradation, and healthy cartilage state is one of the factors that affect osteoarthritis. microRNA-98 (miRNA-98) plays a role in inflammation. This study aims to investigate the levels of CTX-III and miRNA-98 in patients with osteoarthritis and their potential clinical usage.

PATIENTS AND METHODS

Osteoarthritis was diagnosed according to the inclusion and exclusion criteria for osteoarthritis. Patients with osteoarthritis admitted to Jining No. 1 People's Hospital and healthy volunteers were included in this study. ELISA and Western blot analysis were used to detect levels of type III collagen CTX (CTX-III). Real time PCR was used to measure levels of miRNA-98 in the serum of both patients and healthy volunteers.

RESULTS

Levels of CTX-III protein in osteoarthritis patients were significantly higher than that of healthy volunteers (p = 0.0013). Levels of miRNA-98 in the serum of osteoarthritis patients were significantly higher compared to that of healthy volunteers (p = 0.0065). After treatment, levels of CTX-III protein and serum miRNA-98 in patients with osteoarthritis were significantly decreased (p = 0.014, p = 0.021). Levels of CTX-III protein and serum miRNA-98 in patients with osteoarthritis were significantly higher compared to that of healthy volunteers (p = 0.0013).

CONCLUSIONS

Both of the CTX-III and microRNA-98 are potential diagnostic indicators for the osteoarthritis.

microRNA-199a-5p mediates high glucose-induced reactive oxygen species production and apoptosis in INS-1 pancreatic β-cells by targeting SIRT1

OBJECTIVE

Hyperglycemia-induced pancreatic β-cell loss is a pathologic hallmark of type 2 diabetes mellitus (T2DM). This study was conducted to clarify the function of microRNA (miR)-199a-5p in high glucose-elicited β-cell toxicity and associated molecular mechanisms.

MATERIALS AND METHODS

INS-1 rat pancreatic β-cells were cultured under normal (11 mM) or high (30 mM) glucose for 16-72 h and examined for miR-199a-5p expression. Gain and loss-of-function studies were performed to determine the role of miR-199a-5p in high glucose-induced apoptosis and reactive oxygen species (ROS) production. Additionally, the involvement of SIRT1 in the action of miR-199a-5p was checked.

RESULTS

High glucose caused a significant upregulation of miR-199a-5p in INS-1 cells compared to cells under normal glucose conditions. Pre-transfection with anti-miR-199a-5p inhibitors prevented the reduction in cell viability and inhibited ROS generation in INS-1 cells after high glucose treatment. In contrast, overexpression of miR-199a-5p significantly reduced cell viability and promoted apoptosis and ROS formation in INS-1 cells, which was coupled with a downregulation of SIRT1. Knockdown of SIRT1 led to apoptotic death in INS-1 cells. Moreover, enforced expression of SIRT1 blocked miR-199a-5p-induced ROS generation and attenuated high glucose-mediated apoptosis in INS-1 cells.

CONCLUSIONS

miR-199a-5p is upregulated in pancreatic β-cells in response to high glucose and promotes apoptosis and ROS generation by targeting SIRT1. The miR-199a-5p/SIRT1 axis may represent a promising target for the treatment of T2DM.

Abstract P1-12-08: The incidence and outcomes of brain metastases in HER2-positive metastatic breast cancer with the advent of modern anti-HER2 therapies

Background: Human epidermal growth factor receptor 2 (HER2) is over-expressed in approximately 20 - 30% of breast cancers. HER2-positive breast cancers frequently metastasize to the brain. In recent years, many new drugs have been approved for HER2-positive metastatic breast cancer (MBC). In the metastatic setting, trastuzumab was approved in 2000, lapatinib 2007, and pertuzumab and ado-trastuzumab emtansine in 2012. We sought to describe the incidence, time course, and prognostic factors of BM in patients (pts) with HER2+ MBC during the time when dramatic changes in systemic therapy occurred.

Patients/methods: The study included pts with HER2-positive MBC treated at two academic hospitals: Dana Farber Cancer Institute (DFCI) (2000-2007 [DFCI-T1], 2008-2011 [DFCI-T2]) and University of North Carolina (UNC) (2012-2014). We examined the incidence of BM (at diagnosis [dx] and within 1-2 years of MBC dx). We combined the two cohorts to examine outcomes – time to BM, survival following MBC, and survival following BM – using the Kaplan Meier method and Cox regression modeling.

Results: We identified 185 (DFCI n=128, 97 diagnosed 2000-2007 and 31 diagnosed 2008-2011; UNC n=57, all diagnosed 2012-2014) pts with HER2-positive MBC. Through a median of 4 years follow-up after the MBC dx (min 2, max 11), 118 had died and 67 were censored. The median age at MBC dx was 52 (min 25, max 88), 149 (82%) were Caucasian, 88 (48%) had hormone receptor (HR) positive BC, and 67 (37%) had de-novo (i.e., non-recurrent) MBC. BM was present at the MBC dx for 8% of pts in DFCI-T1, 16 % of pts in DFCI-T2, and 16% of pts at UNC. Within 1 year of the MBC dx, BM was present in 21% of DFCI-T1, 29% in DFCI-T2, 23% of UNC pts. Within 2 years of the MBC dx, 67 (36%) pts had developed BM, of which one third (22) were diagnosed at initial MBC presentation. In unadjusted analyses, there were no differences in time to BM dx by age (p=0.2), race (p=0.1) or HR status (p=0.1). The median survival following the development of BM for all pts was 1.5 years. A multivariable model predicting survival after the MBC dx, found factors associated with shorter survival included having (vs. not having) BM at the initial MBC dx, having received (vs. not having received) adjuvant HER2-directed therapy prior to the MBC dx, and having recurrent (vs. de novo) MBC (P≤0.02 for all). Age, HR status, race and time period of MBC dx were not significant in the multivariable model.

Conclusions: Among pts diagnosed in the modern era, after new therapies became available, BM remains a common problem for pts with HER2-positive MBC. While no obvious trends in the incidence of HER2-positive MBC are suggested, conclusions regarding incidence trends should be considered hypothesis-generating until larger, population-based data become available. Nevertheless, a dx of BM early in the course of MBC treatment and prior receipt of adjuvant trastuzumab appeared to confer a more aggressive disease course. Coordinated, prospective collection of the incidence and outcomes of BM among pts with HER2-positive MBC, studies of pts who develop BM &gt;2 years after their MBC dx, and clinical trials of treatment strategies for pts with trastuzumab-resistant BM are needed.

Citation Format: Strulov Shachar S, Deal AM, Vaz-Luis I, Dees EC, Carey LA, Hassett MJ, Garrett AL, Benbow JM, Hughes ME, Mounsey L, Lin N, Anders CK. The incidence and outcomes of brain metastases in HER2-positive metastatic breast cancer with the advent of modern anti-HER2 therapies [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-12-08.

Abstract PD4-01: Acupuncture for chemotherapy-induced peripheral neuropathy in breast cancer, preliminary results of a pilot randomized controlled trial

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is one of the major dose-limiting side effects in breast cancer patients, with up to 97% of patients receiving an adjuvant taxane experiencing this symptom in the months and years after breast cancer treatment. CIPN often leads to loss of physical function; difficulties in activities of daily living and decreased of quality of life (QOL). Few effective interventions have been developed to alleviate CIPN in this patient population. We conducted a pilot randomized controlled trial to assess the feasibility, safety and preliminary effect of an acupuncture intervention on CIPN in breast cancer survivors.

METHODS: Patients with stage I-III breast cancer who were experiencing CIPN after the completion of a taxane-containing adjuvant chemotherapy regimen were enrolled and randomized 1:1 to immediate participation in an acupuncture intervention or to a delayed intervention control group. Participants randomized to the acupuncture arm received 18 sessions of a standardized acupuncture protocol over 8 weeks while the control group received a lower-dose acupuncture protocol consisting of 9 acupuncture sessions over 8 weeks, after the initial 8-week control period. Measures including the Patient Neurotoxicity Questionnaire (PNQ), Functional Assessment of Cancer Therapy Neurotoxicity subscale (FACT-NTX), and the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Chemotherapy-induced Peripheral Neuropathy 20 (EORTC QLQ-CIPN20) were collected at baseline and at 8 weeks after enrollment.

RESULTS: A total of 40 patients were enrolled; 20 were randomized to the immediate acupuncture group and 20 to control. All enrolled patients were female, median age was 54, median time between enrollment and completion of chemotherapy was 14.3 months, and 72.5% of participants were White. Thirty-two patients (84%) completed at least 80% of the required sessions. No serious acupuncture-related side effects were observed. Participants randomized to the acupuncture arm experienced improvements in the PNQ sensory score (p=0.02), FACT-NTX summary score (p=0.002) and EORTC QLQ-CIPN20 score (p=0.006), respectively equivalent to 40%, 36% and 53% improvement in CIPN symptoms, as compared to controls.

MeasurementsTime pointsAcupunctureUsual CareP-valueNMeanSDMeanSDPNQ summary sensory score (0-4)Baseline202.50.82.50.90.97Changes at 8 week15-1.00.9-0.30.60.02FACT-NTX summary score (0-44)Baseline2025.08.422.19.40.40Changes at 8 week159.09.21.25.40.002EORTC QLQ-CIPN20 sensory score (0-100)Baseline2044.919.945.022.30.93Changes at 8 week15-23.818.1-5.16.40.006

CONCLUSIONS: Women with CIPN after adjuvant taxane therapy for early breast cancer experienced a significant and clinically meaningful improvement in neuropathy symptoms as a result of an 8-week acupuncture protocol. Given the prevalence of taxane-induced neuropathy in women treated for early breast cancer, acupuncture could significantly improve QOL and functional status of thousands of women treated for breast cancer every year. Larger studies are needed to confirm these findings and evaluate the impact of acupuncture on functional measures in women with CIPN.

Citation Format: Lu W, Giobbie-Hurder A, Freedman R, Yung R, Lin N, Partridge A, Shockro L, Stecker K, O'Connor KA, Rosenthal DS, Ligibel JA. Acupuncture for chemotherapy-induced peripheral neuropathy in breast cancer, preliminary results of a pilot randomized controlled trial [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD4-01.

Abstract S1-01: Whole exome and transcriptome sequencing of resistant ER+ metastatic breast cancer

Background: While great strides have been made in the treatment of estrogen receptor-positive (ER+) metastatic breast cancer (MBC), therapeutic resistance invariably occurs. A better understanding of the underlying resistance mechanisms is critical to enable durable control of this disease.

Methods: We performed whole exome sequencing (WES) and transcriptome sequencing (RNA-seq) on metastatic tumor biopsies from 88 patients with ER+ MBC who had developed resistance to one or more ER-directed therapies. For 27 of these patients, we sequenced the treatment-naïve primary tumors for comparison to the resistant specimens. Tumors were analyzed for point mutations, insertions/deletions, copy number alterations, translocations, and gene expression. Detailed clinicopathologic data was collected for each patient and linked to the genomic information.

Results: WES of all metastatic samples demonstrated several recurrently altered genes whose incidence differed significantly from primary, treatment-naïve ER+ breast cancers sequenced in the TCGA study (TCGA). These include ESR1 mutations (n=17, 19.3%; 32.86 fold enrichment, q.value&lt;7.5e-12), CCND1 amplification (n=52, 59.1%; 2.3 fold enrichment, q.value&lt;0.0073), and MAP2K4 biallelic inactivation (n=14, 15.9%; 3.04 fold enrichment, q.value&lt; 0.054).

Comparing to matched primary samples from the same patient, many alterations were found to be acquired in several cases, including for ESR1, ERBB2, PIK3CA, PTEN, RB1, AKT1, and others. Initial analysis of RNA-seq data from metastatic samples (n=59) allowed classification of individual resistance mechanisms into broader resistance modes based on the observed transcriptional state.

Conclusions: We present a genomic landscape of resistant ER+ MBC using WES and RNA-seq. Multiple genes were recurrently altered in these tumors at significantly higher rates than in ER+ primary breast cancer. When compared with matched primary tumors from the same patient, alterations in these and other genes were often found to be acquired after treatment, suggesting a role in resistance to ER-directed therapies and/or metastasis. Potential resistance mechanisms appear to fall into several categories; integrating RNA-seq data may enhance the ability to identify these categories even when genomic alterations are not identified. Multiple clinically relevant genomic and molecular alterations are identified in metastatic biopsies– with implications for choice of next therapy, clinical trial eligibility, and novel drug targets.

Citation Format: Cohen O, Kim D, Oh C, Waks A, Oliver N, Helvie K, Marini L, Rotem A, Lloyd M, Stover D, Adalsteinsson V, Freeman S, Ha G, Cibulskis C, Anderka K, Tamayo P, Johannessen C, Krop I, Garraway L, Winer E, Lin N, Wagle N. Whole exome and transcriptome sequencing of resistant ER+ metastatic breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr S1-01.