Abstract B24: Phase II trial of AKT inhibitor MK-2206 in patients with advanced breast cancer who have tumors with PIK3CA or AKT mutations, and/or PTEN loss/PTEN mutation

Background: The PI3K/AKT pathway is activated through PIK3CA or AKT1 mutations and PTEN loss in breast cancer. We conducted a phase II trial with an allosteric AKT Inhibitor MK-2206 in patients with advanced breast cancer who had tumors with PIK3CA/AKT1 mutations and/or PTEN loss/mutation.

Methods: The primary endpoint was objective response rate (ORR). Secondary endpoints were 6-month progression-free survival (6m PFS), predictive and pharmacodynamic markers, safety and tolerability. Patients had pretreatment and on-treatment biopsies as well as collection of peripheral blood mononuclear cells (PBMC) and platelet-rich plasma (PRP). Next-generation sequencing, immunohistochemistry and reverse phase protein arrays (RPPA) were performed.

Results: Twenty-seven patients received MK-2206. Eighteen patients were enrolled into the PIK3CA/AKT1 mutation arm (cohort A): 13 had PIK3CA mutations, four had AKT1 mutations and one had a PIK3CA mutation as well as PTEN loss. ORR and 6m PFS were both 5.6% (1/18), with one patient with HR+ breast cancer and a PIK3CA E542K mutation experiencing a partial response (on treatment for 36 weeks). Nine patients were enrolled on the PTEN loss/mutation arm (cohort B). ORR was 0% and 6m PFS was 11% (1/9), observed in a patient with triple-negative breast cancer and PTEN loss. The study was stopped early due to futility. The most common adverse events were fatigue (48%) and rash (44%). On pretreatment biopsy, PIK3CA and AKT1 mutation status was concordant with archival tissue testing. However, two patients with PTEN loss based on archival testing had PTEN expression on the pretreatment biopsy. MK-2206 treatment was associated with a significant decline in pAKT S473 and pAKT T308 and PI3K activation score in PBMC and PRPs, but not in tumor biopsies. By IHC, there was no significant decrease in median pAKT S473 or Ki-67 staining, but a drop was observed in both responders.

Conclusions: MK-2206 monotherapy had limited clinical activity in advanced breast cancer patients selected for PIK3CA/AKT1 or PTEN mutations or PTEN loss. This may, in part, be due to inadequate target inhibition at tolerable doses in heavily pretreated patients with pathway activation, as well as tumor heterogeneity and evolution in markers such as PTEN conferring challenges in patient selection.

Citation Format: Yan Xing, Nancy U. Lin, Mathew Mauer, Huiqin Chen, Armeen Mahvash, Aysegul Sahin, Argun Akcakanat, Yisheng Li, Vandana Abraham, Jennifer Litton, Mariana Chavez-McGregor, Vicente Valero, Sarina A. Piha-Paul, David Hong, Kim-Anh Do, Emily Tarco, Dianna Riall, Karina Agda Eterovic, Lewis Cantley, Gordon B. Mills, L. Austin Doyle, Eric Winer, Gabriel Hortobagyi, Ana Maria Gonzalez-Angulo, Funda Meric-Bernstam. Phase II trial of AKT inhibitor MK-2206 in patients with advanced breast cancer who have tumors with PIK3CA or AKT mutations, and/or PTEN loss/PTEN mutation [abstract]. In: Proceedings of the AACR Special Conference on Targeting PI3K/mTOR Signaling; 2018 Nov 30-Dec 8; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Res 2020;18(10_Suppl):Abstract nr B24.

Abstract P1-18-20: Breast cancer with HER2 FISH test result in group 2: Should HER2 test be repeated?

Introduction: Interpretation of HER2 result in breast cancer patients with monosomy of CEP17 has been controversial due to the loss of CEP17 signals and the subsequent relatively increased HER2/CEP17 ratio. HER2 FISH group 2 (HER2< 4 and HER2/CEP17 ratio ≥ 2) was historically considered HER2 positive (HER2+) irrespective of the negative HER2 overexpression and anti-HER2 therapy response. The updated 2018 ASCO/CAP guidelines incorporated immunohistochemistry (IHC) results to facilitate HER2 reporting. However both IHC and FISH can be subjective to analytical variables, which can lead to challenge in interpretation cases in this group. This study aimed to assess if repeat IHC and FISH tests could assist final HER2 interpretation for group 2 cases.

Methods: We retrospectively reviewed HER2 FISH cases performed at our institution from 2012 to 2017 and identified 23 of 3554 (0.6%) breast cancer cases with at least one time HER2 FISH result fell into group 2 category. A chart review for clinicopathological characteristics and biomarker status was performed in all 23 cases. The HER2 IHC and FISH tests were repeated for cases with available alternative tumor samples. Final HER2 interpretation was modified by following 2018 ASCO/CAP guidelines.

Results: Patients’ age ranged from 26-67. These tumors were predominantly ductal (n = 17, 74%), high grade (n = 13, 57%), ER positive (n = 17, 74%), and equivocal HER2 (2+) by IHC (n = 15, 60%). These HER2 FISH group 2 cases were from 18 primary tumors and 5 metastatic/recurrent tumors. All 23 cases (100%) were considered HER2 amplified according to 2013 ASCO/CAP guidelines, only 2/23 (9%) can be interpreted as HER2+ in conjunction with their corresponding IHC result according to 2018 ASCO/CAP guidelines. The corresponding primary tumors for the 5 metastatic/recurrent group 2 tumors were 2 HER2+ and 3 HER2-. Repeat HER2 tests were performed in 15 of 18 group 2 primary tumors; the concordance rates between initial and repeat tests were 27% (4/15) for the HER2 FISH group category and 73% (11/15) for the final HER2 results. Three (20%) cases changed from HER2- (group 2 and IHC 2+) to HER2+ (group 1 [HER2/CEP17 ratio ≥ 2 and HER2 ≥ 4] and IHC 2+); one case changed from HER2+ (group 2 and IHC 3+) to HER2- (group 5 [HER2/CEP17 ratio < 2 and HER2< 4] and IHC 1+); and 11 cases remained as HER2- on repeat (4 for group 2 with IHC 1-2+ and 7 for group 5 with IHC 0-2+). Eight of these 15 patients received neoadjuvant chemo and Herceptin therapy, 3 (38%) achieved a complete pathologic response and 5 (62%) did not respond (Table 1). The 3 responders had ductal tumors and at least 40% of Ki67 in contrast the other 5 non-responders with either lobular histology or Ki67 < 40% (p < 0.05).

Conclusion: Breast cancer with a group 2 HER2 FISH result represents heterogeneous populations of tumor cells being originated de novo or preferentially selected secondary to chemotherapy, and leading to challenges in HER2 interpretation. Repeat HER2 IHC and FISH test on alternative samples either different tumor block of the same biopsy or tumor from excision may assist in final classification to guide treatment decision.

Table 1. Repeat HER test in breast cancer patients with initial HER2 FISH test in group 2CaseInitial test on biopsy (IHC/FISH)Repeat test on biopsy (IHC/FISH)Repeat test on excision (IHC/FISH)Final HER2 resultHistologyGradeERKi-67Response to NAC+H12+/Group 22+/Group 1N/APosDuctal3Low Pos40%pCR22+/Group 22+/Group 1N/APosDuctal3Neg90%pCR32+/Group 22+/Group 1N/APosLobular3Pos5%RCB-II43+/Group 2N/A1+/Group 5PosDuctal3Pos15%RCB II51+/Group 20/Group 5N/ANegDuctal3Pos73%pCR62+/Group 2N/A2+/Group 5NegLobular3Pos10%RCB II72+/Group 2N/A1+/Group 2NegDuctal2Pos38%RCB II81+/Group 2N/A2+/Group 2NegDuctal/Lobular3PosNPRCB IINAC+H: Neoadjuvant chemo and HerceptinpCR: complete pathologic responseRCB: residual tumor burden

Citation Format: Hui Chen, Minhua Wang, Hongxia Sun, Jun Gu, Zhenya Tang, Guilin Tang, Steven Sfamenos, Melissa Robinson, Aysegul Sahin. Breast cancer with HER2 FISH test result in group 2: Should HER2 test be repeated? [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-18-20.

Abstract P4-06-03: Assessment of intratumoral heterogeneity in early stage estrogen receptor (ER) positive breast cancer

Introduction: Tumor heterogeneity is a hallmark of cancer and its underlying clinical relevance has been well established across different tumor types. In the context of ER-positive breast cancer, variation in ER expression among different tumors or distinct cell populations within a single tumor are predicted to account for differences in clinical behavior, treatment response, and disease recurrence. However, a clear understanding of the molecular and cellular mechanisms of tumor heterogeneity that are relevant to the prognosis and therapy of early stage ER-positive breast cancer has not been established. Previous results from bulk RNA-sequencing (RNA-seq) of ER-positive biopsies represent an average of gene expression patterns; this might obscure biologically relevant differences between cells. Single-cell RNA-sequencing (scRNA-seq) is an approach to overcome this problem, allowing assessment of intratumoral cell populations and biological systems at unprecedented resolution. In this study, our aim is to compare gene expression profiles of bulk RNA-seq and scRNA-seq from tumor biopsies of early stage ER-positive patients. Methods: Tumor and normal biopsies obtained from ER-positive patients were divided into 3 parts; two being dissociated by enzymatic disaggregation and one by direct total RNA isolation. Tumor tissues were subjected to both scRNA-seq and bulk RNA-seq analyses while single-cell suspension of the normal matched tissue was used for bulk RNA-seq alone. Furthermore, patient-derived organoids were generated from both normal and tumor samples. Single-cell isolation and barcoding were assessed using the 10x Genomics technology followed by RNA sequencing with the Illumina NovaSeq6000 system (50PE), whereas bulk RNA-seq was performed using an Illumina PE150 strategy. Results: Our preliminary data represents an assessment of tumor and normal adjacent tissues collected after mastectomy from an 80-year old ER-positive, PR-positive, HER2-negative patient diagnosed with early stage infiltrating ductal carcinoma in situ (stage IB). scRNA-seq of tumor tissue from this patient identified 10 distinct clusters of cells, consisting of both immune and non-immune stromal populations (epithelial, endothelial, fibroblasts, and immune cells). 95% of single cells were luminal. However, there was a minor group (2%) of cells showing a basal-like signature, which can lead to disease recurrence. Interestingly, although the patient was clinically characterized as HER2-negative by IHC and FISH, HER2 overexpression is observed in the vast majority (95%) of single cells isolated. Furthermore, organoid cultures recapitulated the features of patients' tumors and presented similar transcriptomic profiles. We have adapted similar sequencing and downstream analyses for an additional number of patient biopsies. Our ongoing study is geared towards comparing bulk and single cell transcriptome profiles from these ER-positive cases and identifying overlapping populations that can predict recurrence or novel therapeutic vulnerabilities. Conclusions: Bulk RNA-seq approaches lack the resolution to visualize the true extent of stromal heterogeneity and may mask rare populations or cellular phenotypes that could be critical for tumor survival. ScRNA-seq highlights the dynamic and adaptive nature of all cellular populations within an evolving tumor microenvironment and reveal potential crosstalk between these two compartments. Lastly, establishment of organoid cultures presents the opportunity of high-throughput drug screening studies and the identification of new, patient-tailored therapeutic strategies.

Citation Format: Sofia Mastoraki, Juliana Navarro-Yepes, Tuan Tran, Aysegul Sahin, Kelly Hunt, Nicholas Navin, Khandan Keyomarsi. Assessment of intratumoral heterogeneity in early stage estrogen receptor (ER) positive breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-06-03.

Effects of resveratrol on alpha-amanitin-induced nephrotoxicity in BALB/c mice

Alpha-amanitin (α-AMA), the primary toxin of Amanita phalloides, is known to cause nephrotoxicity and hepatotoxicity. Resveratrol is an antioxidant that has shown efficacy in many nephrotoxicity models. The aim of this study was to investigate the effects of resveratrol against the early and late stages of α-AMA-induced nephrotoxicity, compared to those of silibinin, a well-known antidote for poisoning by α-AMA-containing mushrooms. Mice kidney tissues were obtained from five groups: (1) α-AMA + NS (simultaneous administration of α-AMA and normal saline), (2) α-AMA + SR (simultaneous administration of α-AMA and resveratrol), (3) α-AMA + 12R (resveratrol administration 12 h after α-AMA administration), (4) α-AMA + 24R (resveratrol administration 24 h after α-AMA administration), and (5) α-AMA + Sil (simultaneous administration of α-AMA and silibinin). Histomorphological and biochemical analyses were performed to evaluate kidney damage and oxidant-antioxidant status in the kidney. Scores of renal histomorphological damage decreased significantly in the early resveratrol treatment groups (α-AMA + SR and α-AMA + 12R), compared to those in the α-AMA + NS group (p < 0.05). Catalase levels increased significantly in the α-AMA + SR group, compared to those in the α-AMA + NS group (p < 0.001). Early resveratrol administration within 12 h after α-AMA ingestion may reverse the effects of α-AMA-induced nephrotoxicity, partly through its antioxidant action, thereby suggesting its potential as a treatment for poisoning by α-AMA-containing mushrooms.

Phase II trial of AKT inhibitor MK-2206 in patients with advanced breast cancer who have tumors with PIK3CA or AKT mutations, and/or PTEN loss/PTEN mutation

BACKGROUND

The PI3K/AKT pathway is activated through PIK3CA or AKT1 mutations and PTEN loss in breast cancer. We conducted a phase II trial with an allosteric AKT inhibitor MK-2206 in patients with advanced breast cancer who had tumors with PIK3CA/AKT1 mutations and/or PTEN loss/mutation.

METHODS

The primary endpoint was objective response rate (ORR). Secondary endpoints were 6-month progression-free survival (6 m PFS), predictive and pharmacodynamic markers, safety, and tolerability. Patients had pre-treatment and on-treatment biopsies as well as collection of peripheral blood mononuclear cells (PBMC) and platelet-rich plasma (PRP). Next-generation sequencing, immunohistochemistry, and reverse phase protein arrays (RPPA) were performed.

RESULTS

Twenty-seven patients received MK-2206. Eighteen patients were enrolled into the PIK3CA/AKT1 mutation arm (cohort A): 13 had PIK3CA mutations, four had AKT1 mutations, and one had a PIK3CA mutation as well as PTEN loss. ORR and 6 m PFS were both 5.6% (1/18), with one patient with HR+ breast cancer and a PIK3CA E542K mutation experiencing a partial response (on treatment for 36 weeks). Nine patients were enrolled on the PTEN loss/mutation arm (cohort B). ORR was 0% and 6 m PFS was 11% (1/9), observed in a patient with triple-negative breast cancer and PTEN loss. The study was stopped early due to futility. The most common adverse events were fatigue (48%) and rash (44%). On pre-treatment biopsy, PIK3CA and AKT1 mutation status was concordant with archival tissue testing. However, two patients with PTEN loss based on archival testing had PTEN expression on the pre-treatment biopsy. MK-2206 treatment was associated with a significant decline in pAKT S473 and pAKT T308 and PI3K activation score in PBMC and PRPs, but not in tumor biopsies. By IHC, there was no significant decrease in median pAKT S473 or Ki-67 staining, but a drop was observed in both responders.

CONCLUSIONS

MK-2206 monotherapy had limited clinical activity in advanced breast cancer patients selected for PIK3CA/AKT1 or PTEN mutations or PTEN loss. This may, in part, be due to inadequate target inhibition at tolerable doses in heavily pre-treated patients with pathway activation, as well as tumor heterogeneity and evolution in markers such as PTEN conferring challenges in patient selection.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01277757 . Registered 13 January 2011.

Combined Inhibition of STAT3 and DNA Repair in Palbociclib-Resistant ER-Positive Breast Cancer

PURPOSE

Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors are currently used in combination with endocrine therapy to treat advanced hormone receptor-positive, HER2-negative breast cancer. Although this treatment doubles time to progression compared with endocrine therapy alone, about 25%-35% of patients do not respond, and almost all patients eventually acquire resistance. Discerning the mechanisms of resistance to CDK4/6 inhibition is crucial in devising alternative treatment strategies.

EXPERIMENTAL DESIGN

Palbociclib-resistant cells (MCF-7 and T47D) were generated in a step-wise dose-escalading fashion. Whole-exome sequencing, genome-wide expression analysis, and proteomic analysis were performed in both resistant and parental (sensitive) cells. Pathway alteration was assessed mechanistically and pharmacologically. Biomarkers of altered pathways were examined in tumor samples from patients with palbociclib-treated breast cancer whose disease progressed while on treatment.

RESULTS

Palbociclib-resistant cells are cross-resistant to other CDK4/6 inhibitors and are also resistant to endocrine therapy (estrogen receptor downregulation). IL6/STAT3 pathway is induced, whereas DNA repair and estrogen receptor pathways are downregulated in the resistant cells. Combined inhibition of STAT3 and PARP significantly increased cell death in the resistant cells. Matched tumor samples from patients with breast cancer who progressed on palbociclib were examined for deregulation of estrogen receptor, DNA repair, and IL6/STAT3 signaling, and results revealed that these pathways are all altered as compared with the pretreatment tumor samples.

CONCLUSIONS

Palbociclib resistance induces endocrine resistance, estrogen receptor downregulation, and alteration of IL6/STAT3 and DNA damage response pathways in cell lines and patient samples. Targeting IL6/STAT3 activity and DNA repair deficiency using a specific STAT3 inhibitor combined with a PARP inhibitor could effectively treat acquired resistance to palbociclib.

Characterization of bevacizumab by dynamic light scattering while maintaining its native structure

Bevacizumab, is a humanized monoclonal antibody and patents on Avastin® (Bevacizumab, Roche) will expire in the US in 2019 and in Europe in 2022. Therefore, bevacizumab is a popular target for biosimilar developers. One of the most common problems in the formulation of antibody drugs is protein aggregation. Dynamic light scattering (DLS) is a well-established method for the determination of hydrodynamic dimensions, aggregates, and aggregation points of proteins. In contradistinction to other techniques that require diluted samples or specific conditions, proteins and aggregates can maintain their native structure during DLS measurements. In recent studies, bevacizumab was characterized by DLS using diluted samples. In this study, we aimed at investigating the hydrodynamic dimensions, aggregates, and aggregation onset of bevacizumab (Altuzan®, Turkey, Roche) by DLS, while maintaining its native structure. The intensity, volume, and number-based particle size distribution profiles of the test samples were evaluated and the aggregation onset of the formulation was successfully determined against increasing temperature. It is shown that the preservation of the native structure of commercial formulations in DLS measurements provides an opportunity to the characterization of commercial products and development of biosimilars.

The diagnostic value of the serum irisin level in patients with acute pericarditis and acute myopericarditis

OBJECTIVE

This preliminary study aims to examine a change in the blood levels of irisin in patients with acute pericarditis (AP) and acute myopericarditis (AMP) and examine the diagnostic value of the serum irisin level in AP and AMP.

METHODS

10 patients, who applied to the emergency service and cardiology clinic with chest pain and who were diagnosed with AP and 5 patients, who were diagnosed with AMP as a result of routine examinations, were included in the study. The basal laboratory parameters, echocardiography findings and serum irisin levels of the patients and during check one month later were examined.

RESULTS

While the basal irisin levels were found to be significantly low in the AMP group and high during the check (6.6 ± 1.58, 8.19 ± 1.43, respectively), no statistically significant difference was determined (p = 0.23). It was observed that the basal and control irisin levels did not vary significantly in the AP group (8.03 ± 1.6, 8.19 ± 1.43, respectively) (p = 0.84).

CONCLUSION

In this preliminary study, the basal irisin levels were found to be significantly low in the AMP group, while there was no statistically significant difference between the basal irisin levels and control irisin levels in the AP and AMP groups (Tab. 5, Ref. 17).

Using PVA and TPGS as combined emulsifier in nanoprecipitation method improves characteristics and anticancer activity of ibuprofen loaded PLGA nanoparticles

In the preparation of nanoparticles (NPs) by the nanoprecipitation method, emulsifiers play a key role for NPs' characteristics. The present study aimed to investigate the combined emulsifier effect on ibuprofen loaded poly(lactic-co-glycolic acid) (PLGA) NPs' characteristics and anticancer activity. Ibuprofen loaded PLGA NPs were prepared by nanoprecipitation using different concentrations of PVA (poly(vinyl alcohol)) or PVA-TPGS (d-α-tocopherol polyethylene glycol 1000 succinate) combination as emulsifier. It was found that encapsulation efficiencies of NPs varied between 17.9 and 41.9 % and the highest encapsulation efficiency was obtained with 0.5% PVA + 0.1% TPGS (coded as PLGA PVA/TPGS NPs). PLGA PVA/TPGS NPs were characterized and compared with PLGA PVA NPs, which was obtained by 0.5% PVA alone. Polydispersity index of PLGA PVA/TPGS and PLGA PVA NPs were found to be 0.08 and 0.15, respectively. Incorporation of TPGS with PVA slightly decreased the initial ibuprofen release. Transmission electron microscopy analyses demonstrated a nearly uniform particle size distribution and spherical particle shape of the PLGA PVA/TPGS NPs. Additionally, PLGA PVA/TPGS NPs were significantly more cytotoxic than PLGA PVA NPs on the MCF-7 (human breast adenocarcinoma cells) and Caco-2 (human epithelial colorectal adenocarcinoma) cells (p<0.05). Also PLGA PVA/TPGS NPs were not cytotoxic on normal cells (L929, mouse healthy fibroblast cells) (p>0.05). In conclusion, these results indicated that using a combination of TPGS and PVA as an emulsifier in nanoprecipitation could be a promising approach for preparing ibuprofen loaded PLGA NPs because of their improved characteristics and anticancer activity.

Abstract 1105: Tumor cells of the early metastatic process show up regulation of cytokine genes involved in migration of inflammatory cells

Background: Patients with metastatic breast cancer have poorer prognosis and distant metastasis is the main cause of breast cancer (BC) deaths. Hence, better understanding of the early metastatic process is needed. Most BC metastasize primarily lymphogenic and tumor cells within the lympho-vascular space are the first clear visible step in the metastatic process. However, these cells are hardly investigated since the tumor area is very small and therefore difficult to analyze. In this study we wanted to show that tumor cells within the lympho-vascular space can be analyzed for gene expression and that differences compared between main tumor mass and lympho vascular invasion (LVI) occur. Methods: We included 20 BCs diagnosed at UT MD Anderson Cancer Center between 2010 and 2015. The cohort showed the following characteristics: Invasive ductal (n=18), lobular (n=1), ductulo-lobular (n=1), ER positive (n=18), ER negative (n=2), PgR positive (n=15), PgR negative (n=5), Her2 negative (n=16), and Her2 positive (n=4). Suitable FFPE tissue blocks were identified for all BCs. Ten µm sections were performed, air-dried and stained with methyl-green for visualization of the morphology. Macro-dissection and measurement of the tumor area (LVI) was done under a stereo microscope. Afterwards, HTG Seq quantitative assay of the oncology biomarker panel (2,560genes) was performed with some modifications to the standard protocol. Results: The macro-dissection was successful for both, LVI and main tumor mass, in 19 BCs. The dissected areas were between 11-60mm2. Eighteen samples could be included for RNA expression analysis. The main tumor mass and LVI showed clearly different expression patterns (clustering). LVI showed down regulation of genes coding for collagens (COL3A1, COL5A1), or genes involved in the interaction with the extracellular matrix (SPARC, VCAN). Up regulation was seen for genes coding for chemotactic factors involved in migration of inflammatory cells such as CCL18 for B-lymphocytes, CCL27 that seems to play a role in homing of lymphocytes to the skin, or CCL2 that is involved in recruiting monocytes and basophils. Conclusion: We showed that RNA expression analysis is feasible on small amount of tumor cells dissected from LVI that were stained with methyl green. Additionally, we could show that tumor cells from the main tumor mass and LVI have different gene expression levels and show clear clustering. Down regulation was seen in genes interacting with the extracellular matrix may indicating that these interactions are not needed when floating in lymphatic vessels. Interestingly, LVI showed upregulation of genes involved in the migration of white blood cells what could be an indication that tumor cells might relay on the same cytokines for migration in lymphatic vessels as inflammatory cells.

Citation Format: Coya Tapia, Xiaoping Su, Ximing Tang, Lakshmi Kakaral, Aysegul Sahin, Wei Lu, Ignacio I. Wistuba. Tumor cells of the early metastatic process show up regulation of cytokine genes involved in migration of inflammatory cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1105.

Survival Outcomes by TP53 Mutation Status in Metastatic Breast Cancer

Purpose

We sought to determine the significant genomic alterations in patients with metastatic breast cancer (MBC), and survival outcomes in common genotypes.

Patients and Methods

High-depth next generation sequencing was performed for 202 genes in tumor and normal DNA from 257 patients with MBC, including 165 patients with ER/PR+ HER2- (hormone receptor positive, HR+ positive), 32 patients with HER2+ and 60 patients with triple negative (ER/PR/HER2-) cancer. Kaplan Meier survival analysis was performed in our discovery set, in breast cancer patients analyzed in The Cancer Genome Atlas, and in a separate cohort of 98 patients with MBC who underwent clinical genomic testing.

Results

Significantly mutated genes (SMGs) varied by histology and tumor subtype, but TP53 was a SMG in all three subtypes. The most SMGs in HR+ patients included PIK3CA (32%), TP53 (29%), GATA3 (15%), CDH1 (8%), MAP3K1 (8%), PTEN (5%), TGFBR2 (4%), AKT1 (4%), and MAP2K4 (4%). TP53 mutations were associated with shorter recurrence-free survival (P=0.004), progression-free survival (P=0.00057) and overall survival (P=0.003). Further, TP53 status was prognostic among HR+ patients with PIK3CA mutations. TP53 mutations were also associated with poorer overall survival in the 442 HR+ breast cancer patients in the TCGA (P=0.042) and in an independent set of 96 HR+ MBC who underwent clinical sequencing (P=0.0004).

Conclusions

SMGs differ by tumor subtype but TP53 is significantly mutated in all three breast cancer subtypes. TP53 mutations are associated with poor prognosis in HR+ breast cancer. TP53 mutations should be considered in the design and interpretation of precision oncology trials.

Development and validation of a LC-FL method for the simultaneous determination of doxorubicin and celecoxib in nanoparticulate fixed dose combination (NanoFDC)

An isocratic reversed phase HPLC method for the simultaneous determination of doxorubicine (DOX) and celecoxib (CXB) out of a nanoparticulate fixed dose combination (NanoFDC) was developed and validated. Linearity of the results was demonstrated from 1-11 μg/mL for both components. Lower limits of detection were determined as 7 ng/mL for DOX and 13 ng/mL for CXB. Total run time was approximately 15 min.

DCIS Margins and Breast Conservation: MD Anderson Cancer Center Multidisciplinary Practice Guidelines and Outcomes

Recent published guidelines suggest that adequate margins for DCIS should be ≥ 2 mm after breast conserving surgery followed by radiotherapy (RT). Many groups now use this guideline as an absolute indication for additional surgery. This article describes detailed multidisciplinary practices including extensive preoperative/intraoperative pathologic/histologic image-guided assessment of margins, offering some patients with small low/intermediate grade DCIS no RT, the use/magnitude of radiation boost tailoring to margin width, and endocrine therapy for ER-positive DCIS. Use of these protocols over the past 20-years has resulted in 10-year local recurrence rates below 5% for patients with negative margins < 2 mm who received RT. Patients with margins < 2 mm who do not receive RT experience significantly higher local failure rates. Thus, there is not an absolute need to achieve wider negative surgical margins when < 2 mm for patients treated with RT and this should be determined by the multidisciplinary team. Utilization of these multidisciplinary treatment protocols and techniques may not be exportable and extrapolated to all hospitals, breast programs and systems as they can be complex and resource intensive.

The effect of mad honey on testosterone levels of male rats

OBJECTIVE

We aimed to investigate the effect of mad honey on sexual performance.

BACKGROUND

In traditional medicine in Turkey, mad honey is used to improve appetite, to heighten mental alertness, to reduce joint pain, to eliminate gastrointestinal system pains and to increase sexual performance.

METHODS

In this experimental animal study eighteen Sprague Dawley male rats were randomized into three groups, a control group, a normal honey group and a mad honey group. Rats in the treatment groups were given a daily dose of 80 mg/kg normal honey or mad honey throughout the 30-day study period. Total testosterone, free testosterone, FSH, LH, estradiol, and progesterone levels were subsequently investigated from blood sera on day 30.

RESULTS

Comparison of blood total testosterone levels among the groups revealed significantly higher levels in the mad honey group compared to the normal honey and control groups (p = 0.006, p = 0.00). Free testosterone levels were also significantly higher in the mad honey group than in the normal honey and control groups (p = 0.023, p = 0.01). No statistically significant differences were determined for other hormonal measurements.

CONCLUSIONS

This study revealed a significant increase in both total and free testosterone levels in mad-honey group (Tab. 1, Fig. 2, Ref. 16).

Genome-wide copy number aberrations and HER2 and FGFR1 alterations in primary breast cancer by molecular inversion probe microarray

Breast cancer remains the second leading cause of cancer-related death in women despite stratification based on standard hormonal receptor (HR) and HER2 testing. Additional prognostic markers are needed to improve breast cancer treatment. Chromothripsis, a catastrophic genome rearrangement, has been described recently in various cancer genomes and affects cancer progression and prognosis. However, little is known about chromothripsis in breast cancer. To identify novel prognostic biomarkers in breast cancer, we used molecular inversion probe (MIP) microarray to explore genome-wide copy number aberrations (CNA) and breast cancer-related gene alterations in DNA extracted from formalin-fixed paraffin-embedded tissue. We examined 42 primary breast cancers with known HR and HER2 status assessed via immunohistochemistry and FISH and analyzed MIP microarray results for correlation with standard tests and survival outcomes. Global genome-wide CNA ranged from 0.2% to 65.7%. Chromothripsis-like patterns were observed in 23/38 (61%) cases and were more prevalent in cases with ≥10% CNA (20/26, 77%) than in cases with <10% CNA (3/12, 25%; p<0.01). Most frequently involved chromosomal segment was 17q12-q21, the HER2 locus. Chromothripsis-like patterns involving 17q12 were observed in 8/19 (42%) of HER2-amplified tumors but not in any of the tumors without HER2 amplification (0/19; p<0.01). HER2 amplification detected by MIP microarray was 95% concordant with conventional testing (39/41). Interestingly, 21% of patients (9/42) had fibroblast growth factor receptor 1 (FGFR1)amplification and had a 460% higher risk for mortality than those without FGFR1 amplification (p<0.01). In summary, MIP microarray provided a robust assessment of genomic CNA of breast cancer.

Breast cancer molecular subtypes: from TNBC to QNBC

Treatment protocols for breast cancer depend predominantly on receptor status with respect to estrogen (estrogen receptor alpha), progesterone (progesterone receptor) and human epidermal growth factor [human epidermal growth factor receptor 2 (HER2)]. The presence of one or more of these receptors suggests that a treatment targeting these pathways might be effective, while the absence of, or in the case of HER2, lack of overexpression of, all of these receptors, termed triple negative breast cancer (TNBC), indicates a need for the more toxic chemotherapy. In an effort to develop targeted therapies for TNBC, it will be necessary to differentiate among specific TNBC subtypes. The subset of TNBC that expresses androgen receptor (AR) has been determined to express genes consistent with a luminal subtype and therefore may be amenable to therapies targeting either AR, itself, or other pathways typical of a luminal subtype. Recent investigations of the AR signal pathway within breast cancer lead to AR as a significant target for breast cancer therapy with several clinical trials currently in progress. The subclass of TNBC that lacks AR, which we have termed quadruple negative breast cancer (QNBC) currently lacks a defined targetable pathway. Unlike AR-positive TNBC, QNBC predominantly exhibits a basal-like molecular subtype. Several subtypes and related pathway proteins are preferentially expressed in QNBC that may serve as effective targets for treatment, such as ACSL4, SKP2 and EGFR. ACSL4 expression has been demonstrated to be inversely correlated with expression of hormone/growth factor receptors and may thus serve as a biomarker for QNBC as well as a target for therapy. In the following review we summarize some of the current efforts to develop alternatives to chemotherapy for TNBC and QNBC.

Abstract 907: Brain microenvironment induced PTEN loss by microRNAs promotes brain metastasis

Metastasis is the number one cause of cancer-related mortality. Major neoplastic diseases such as melanoma, lung, breast, and colon cancers have high incidences of brain metastases. One-year survival after diagnosis of brain metastasis is less than 20%. Cancer cells dynamically interacts with specific organ microenvironments to establish metastasis as depicted by the “seed and soil” hypothesis. Yet it is unclear when and how disseminated tumor cells acquire the essential traits from the brain microenvironment that primes their subsequent metastatic outgrowth.

Here we found that primary tumor cells with normal PTEN expression lose PTEN after dissemination to the brain, but not to other organs. Metastatic brain tumor cells that have experienced PTEN loss have PTEN levels restored once they leave the brain. This brain microenvironment-dependent, reversible PTEN mRNA and protein down-regulation is epigenetically regulated by microRNAs (miRNAs) from astrocyte-derived exosomes. Furthermore, this adaptive PTEN loss in brain metastatic tumor cells leads to an increased secretion of cytokine chemokine (C-C motif) ligand 2 (CCL2), which recruits Iba1+ myeloid cells that reciprocally enhance outgrowth of brain metastatic tumor cells via enhanced proliferation and reduced apoptosis.

Our findings signify the dynamic and reciprocal cross-talk between tumor cells and other brain stromal cells. Disseminated tumor cells acquire the essential traits from the microenvironment of brain that prime their outgrowth. Importantly, our finding provides new opportunities for effective anti-metastasis therapies: inhibiting CCL2 might be an effective therapeutic intervention of life-threatening brain metastases.

Citation Format: Lin Zhang, Siyaun Zhang, Jun Yao, Frank J. Lowery Lowery, Qingling Zhang, Wen-Chien Huang, Ping Li, Min Li, Xiao Wang, Chenyu Zhang, Hai Wang, Kenneth Ellis, Mujeeburahiman Cheerathodi, Joseph McCarty, Diane Palmieri, Patricia Steeg, Jodi S Saunus, Sunil Lakhani, Suyun Huang, Aysegul Sahin, Kenneth Aldape, Dihua Yu. Brain microenvironment induced PTEN loss by microRNAs promotes brain metastasis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 907.

Dissection of Signaling Pathways in Fourteen Breast Cancer Cell Lines Using Reverse-Phase Protein Lysate Microarray

Signal transduction pathways play a crucial role in breast cancer development, progression, and response to different therapies. A major problem in breast cancer therapy is the heterogeneity among different tumor types and cell lines commonly used in preclinical studies. To characterize the signaling pathways of some of the commonly used breast cancer cell lines and dissect the relationship among a number of pathways and some key genetic and molecular events in breast cancer development, such as p53 mutation, ErbB2 expression, and estrogen receptor (ER)/progesterone receptor (PR) status, we performed pathway profiling of 14 breast cancer cell lines by measuring the expression and phosphorylation status of 40 different cell signaling proteins with 53 specific antibodies using a protein lysate array. Cluster analysis of the expression data showed that there was close clustering of phosphatidylinositol 3-kinase, Akt, mammalian target of rapamycin (mTOR), Src, and platelet-derived growth factor receptor β (PDGFRβ) in all of the cell lines. The most differentially expressed proteins between ER- and PR-positive and ER- and PR-negative breast cells were mTOR, Akt (pThr308), PDGFRβ, PDGFRβ (pTyr751), panSrc, Akt (pSer473), insulin-like growth factor-binding protein 5 (IGFBP5), Src (pTyr418), mTOR (pSer2448), and IGFBP2. Many apoptotic proteins, such as apoptosis-inducing factor, IGFBP3, bad, bax, and cleaved caspase 9, were overexpressed in mutant p53-carrying breast cancer cells. Hexokinase isoenzyme 1, ND2, and c-kit were the most differentially expressed proteins in high and low ErbB2-expressing breast cancer cells. This study demonstrated that ER/PR status, ErbB2 expression, and p53 status are major molecules that impact downstream signaling pathways.