Tia L. Harmon

Obesity induced a leptin-Notch signaling axis in breast cancer

To investigate whether obesity induces a leptin‐Notch signaling axis in breast cancer (BC), leptin‐induced Notch was determined in human MCF‐7 and MDA‐MB231 and mouse E0771 cells and in E0771‐BC hosted by syngeneic lean and diet‐induced obesity (DIO) C57BL/6J female mice. Lean and DIO mice were treated for 3 weeks with leptin inhibitor (PEG‐LPrA2) 1 week after the inoculation of E0771 cells. Leptin induced Notch1, 3 and 4 in BC cells, but Notch2 expression showed opposite pattern in MCF‐7 compared to MDA‐MB231 cells. Notch loss‐of‐function (DAPT and dominant negative [R218H] RBP‐Jk [CSL/CBF1]) showed that a functional leptin‐Notch signaling axis was involved in the proliferation and migration of E0771 cells. E0771‐BC onset was affected by obesity (lean mice7/10 [70%] vs. DIO mice: 11/12 [92%]; Pearson χ2: p = 0.06]). PEG‐LPrA2 significantly reduced BC growth (untreated: 19/42; [45%] vs. treated: 8/42 [19%]; Pearson χ2: p = 0.008). PEG‐LPrA2 did not influence the caloric intake of mice but increased carcass and/or body weights of lean and DIO mice inoculated with E0771 cells, which could be related to the improvement of health conditions (less aggressive disease). Importantly, BC from obese mice had higher levels of Notch3, JAG1 and survivin than lean mice. Inhibition of leptin signaling reduced protein levels of Notch (NICD1, NICD4, Notch3, JAG1 and survivin) and significantly decreased mRNA expression of Notch receptors, ligands and targets. PEG‐LPrAs effects were more prominent in DIO mice. Present data suggest that leptin induces Notch, which could be involved in the reported higher incidence and aggressiveness and, poor prognosis of BC in obese patients.

Leptin-Notch signaling axis is involved in pancreatic cancer progression.

Pancreatic cancer (PC) shows a high death rate. PC incidence and prognosis are affected by obesity, a pandemic characterized by high levels of leptin. Notch is upregulated by leptin in breast cancer. Thus, leptin and Notch crosstalk could influence PC progression. Here we investigated in PC cell lines (BxPC-3, MiaPaCa-2, Panc-1, AsPC-1), derived tumorspheres and xenografts whether a functional leptin-Notch axis affects PC progression and expansion of pancreatic cancer stem cells (PCSC). PC cells and tumorspheres were treated with leptin and inhibitors of Notch (gamma-secretase inhibitor, DAPT) and leptin (iron oxide nanoparticle-leptin peptide receptor antagonist 2, IONP-LPrA2). Leptin treatment increased cell cycle progression and proliferation, and the expression of Notch receptors, ligands and targeted molecules (Notch1-4, DLL4, JAG1, Survivin and Hey2), PCSC markers (CD24/CD44/ESA, ALDH, CD133, Oct-4), ABCB1 protein, as well as tumorsphere formation. Leptin-induced effects on PC and tumorspheres were decreased by IONP-LPrA2 and DAPT. PC cells secreted leptin and expressed the leptin receptor, OB-R, which indicates a leptin autocrine/paracrine signaling loop could also affect tumor progression. IONP-LPrA2 treatment delayed the onset of MiaPaCa-2 xenografts, and decreased tumor growth and the expression of proliferation and PCSC markers. Present data suggest that leptin-Notch axis is involved in PC. PC has no targeted therapy and is mainly treated with chemotherapy, whose efficiency could be decreased by leptin and Notch activities. Thus, the leptin-Notch axis could be a novel therapeutic target, particularly for obese PC patients.

Nanoparticle-linked antagonist for leptin signaling inhibition in breast cancer

AIM To develop a leptin peptide receptor antagonist linked to nanoparticles and determine its effect on viability of breast cancer cells. METHODS The leptin antagonist, LPrA2, was coupled via EDAC [1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide] to iron oxide nanoparticles (IONP-LPrA2) to increase its efficacy. IONP-LPrA2 conjugation was confirmed by Western blot and nanoparticle tracking analysis. Human triple negative breast cancer (TNBC) MDA-MB-231, HCC1806 and estrogen receptor positive (ER+) MCF-7 cells were analyzed for the expression of the leptin receptor, Ob-R. The effects of leptin and antagonist on levels of leptin-induced STAT3 phosphorylation and cyclin D1, cell cycle progression, cell proliferation, and tumorsphere formation in breast cancer cells were determined. Doses of the chemotherapeutics [cisplatin (Cis), cyclophosphamide (CTX), doxorubicin (Dox) and paclitaxel (PTX)] to effectively reduce cell viability were calculated. The effects of combination treatments of IONP-LPrA2 and chemotherapeutics on cell viability were determined. RESULTS Western blot analysis of coupling reaction products identified IONP-LPrA2 at approximately 100 kD. IONP-LPrA2 significantly decreased leptin-induced pSTAT3 levels in HCC1806 cells and drastically decreased cyclin D1 levels in all cell lines. IONP-LPrA2 significantly reduced leptin-induced S phase progression and cell proliferation in all breast cancer cell lines and the formation of tumorspheres in MDA-MB-231 cells. Also, IONP-LPrA2 showed an additive effect on the reduction of breast cancer cell survival with chemotherapeutics. Cis plus IONP-LPrA2 produced a significant reduction in the survival of MDA-MB-231 and HCC1806 cells. CTX plus IONP-LPrA2 caused a significant decrease in the survival of MDA-MB-231 cells. Dox plus IONP-LPrA2 caused a marked reduction in the survival of HCC1806 cells. Although, PTX plus IONP-LPrA2 did not have a major effect on the viability of the breast cancer cells when compared to PTX alone. CONCLUSION Present data indicate that IONP-LPrA2 may be a useful adjuvant for chemotherapeutic treatment of breast cancer, particularly for TNBC which lacks targeted therapeutic options.

Abstract C52: Targeting the obesity/leptin link to TNBC: A breast cancer disparity problem

Triple Negative Breast Cancer (TNBC) is an aggressive cancer associated with poor prognosis and is difficult to treat. Standard therapy for TNBC includes a combination of chemotherapeutic drugs: doxorubicin (DOX), paclitaxel (TAX), and cyclophosphamide (CTX). Current epidemiological data show that obesity increases TNBC incidence, which is more relevant for African American women. Recent findings suggest that leptin (an adipokine increased in obesity) is involved in TNBC acquired drug resistance via induction of breast cancer stem cells (BCSCs). Understanding the role of obesity in TNBC is vital to the development of new and effective therapies. Chemotherapeutic drugs exhibit shortcomings that may be due to increased drug resistance, survival, proliferation, and angiogenic signal redundancy induced by leptin. Our lab has developed and tested a novel, specific inhibitor of leptin signaling, LPrA2. A pegylated derivative of LPrA2 (PEG-LPrA2) has previously shown to enhance, 68 fold, LPrA29s bioavailability in mouse breast cancer models. The objective of this study was to determine the adjuvant effects of PEG-LPrA2 on TNBC in vitro. We hypothesized that PEG-LPrA2 can serve as an adjuvant for standard TNBC chemotherapeutics. This adjuvant would allow for the reduction of chemoresistance and TNBC recurrence. It could also reduce chemotherapeutic dose and undesirable side effects associated with standard therapy for the disease. Two human TNBC cell lines were cultured: MDA-MB-231 (highly metastatic) and MDA-MB-468 (minimally invasive). Cellometer imaging technologies were used to determine S-phase progression in cells treated with PEG-LPrA2 and leptin. Flow cytometry technologies were used to determine the effects of leptin on BCSC surface markers. Additionally, in vitro toxicity of PEG-LPrA2 was tested in non-malignant mammary cells (MCF-10A) via MTT assay. Our data shows that leptin (1.2 nM, equivalent to serum levels of overweight individuals) induced S-phase progression and increased BCSC markers and the formation of TNBC tumorspheres. Remarkably, PEG-LPrA2 (1.2 nM) abrogated leptin induction of S-phase, BCSC markers, and tumorspheres. It also showed no toxicity in non-malignant cells. These results suggest leptin-signaling inhibition could be used as an adjuvant strategy for chemotherapy of TNBC. These results are most relevant for obese African American women suffering from TNBC. Citation Format: Courtney D. Dill, Adriana Harbuzariu, Tia L. Harmon, Crystal C. Lipsey, Ayobami Loye, Ruben Rene Gonzalez-Perez. Targeting the obesity/leptin link to TNBC: A breast cancer disparity problem. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr C52.

Abstract B26: Leptin affects proliferation, stem cells and chemotherapeutic treatment outcome of pancreatic cancer: A link to health disparity

Background: Pancreatic cancer (PC) is an aggressive disease that is in most cases advanced at the time of diagnosis. The overall 5-year survival rate for PC patients is less than 5 %. African-Americans show the highest incidence of obesity and PC as well as mortality rate. How obesity is associated to PC incidence and health disparity is still an unanswered question. High levels of leptin shown by obese African American patients could impact negatively on PC. We hypothesize that leptin signaling induces PC proliferation, stem cells (PCSC) and drug resistance. Methods: Human PC cell lines derived from primary pancreatic adenocarcinoma (Panc-1 and MiaPaCa-2-highly aggressive, BxPC-3-less aggressive) and from metastatic tumor (AsPC-1) were challenged with leptin and chemotherapeutic agents. Cell proliferation, apoptosis rate, and the expression levels of molecular markers were analyzed. PCSC markers were determined in cell lines and tumor biopsies. Effects of leptin and chemotherapeutics on PC-tumorsphere formation were also determined. Results: Leptin stimulated proliferation of PC cells, induced the expression of PCSC markers and increased tumorsphere formation. Moreover, leptin impaired the efficacy of chemotherapeutics on PC cells. Conclusions: Present data suggest leptin is a proliferative and survival factor for PC that reduces chemotherapeutic effectiveness. These observations are of paramount importance for obese African American PC patients, who show the highest levels of leptin, poor prognosis and outcome of chemotherapeutic treatment. Acknowledgements: this work was supported by the DOD W81XWH-13-1-0382; NIH/SBIR 1R41CA183399-01A1; Pilot Project Award from MSM/Tuskegee University/UAB Cancer Center Partnership grant 5U54CA118638; PC SPORE Grant from UAB to RRGP, and facilities and support services at Morehouse School of Medicine (1G12RR026250-03; NIH RR03034 and 1C06 RR18386). Citation Format: Adriana Harbuzariu, Danielle S. Daley-Brown, Tia L. Harmon, Robin C. Garrison, Derrick J. Beech, Frederick D. Cason, Christopher Klug, Ruben R. Gonzalez-Perez. Leptin affects proliferation, stem cells and chemotherapeutic treatment outcome of pancreatic cancer: A link to health disparity. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr B26.

Abstract B31: A new approach to targeted therapy for obesity-related pancreatic adenocarcinoma

Background: Obesity is an important risk factor of Pancreatic Adenocarcinoma (PA) and it is characterized by the accumulation of excessive body fat and a Body Mass Index (BMI) value greater than 30. Obesity is also characterized by high levels of leptin, which has been consistently associated with the development of many different cancer including pancreatic cancer. Obesity can also alter the epigenome via epigenetics changes as DNA methylation and histones acetylation. Histone lysine residues can be acetylated by Histone Acetyltransferases or deacetylated by Histone Deacetylases (HDAC). Leptin can induce the proliferation of Pancreatic Cancer Stem Cells (PCSC), which are responsible for chemoresistance, invasiveness and reoccurrence of PA. PCSC express specific cell markers and can form tumorspheres in vitro. Our lab developed a leptin antagonist named LPrA2, which was bound to iron oxide nanoparticle (IONP-LPrA2) in order to increase its effectiveness and bioavailability. Methods: The adjuvant effects of IONP-LPrA2 in combination of chemotherapeutic drugs on PCSC and tumorspheres formation in low attachment plates were determined. Additionally, the effects of IONP-LPrA2 in combination with chemotherapeutic drugs on the differential expression of epigenetic markers HDAC-1, HDAC-2, and HDAC-8 were investigated. The PA cells were cultured in vitro and treated with leptin, IONP-LPrA2, and chemotherapeutics. Then, the expression of epigenetic and PCSC markers, cell proliferation and survival were determined via Nexcelom cellometer or Guava EasyCyte flow cytometer analyses. Results were assessed by western blot analysis. Results: Leptin affects the level of some HDACs and PCSC markers. That was abrogated by IONP-LPrA2. Chemotherapeutics showed differential effects on the epigenetic and PCSC markers and on tumorspheres formation by PA cells. Conclusion: These findings suggest that IONP-LPrA2 could be useful to design new PA therapies in combination with chemotherapeutics. Furthermore, IONP-LPrA2 may increase the efficiency of chemotherapeutic drug Gemcitabine. These results could be most relevant for obese patients that show the highest incidence of PA and lowest survival rate. Citation Format: Cynthia Ines Mantho Tchio, Adriana Harbuzariu, Tia L. Harmon, Derreck J. Beech, Ruben R. Gonzalez-Perez. A new approach to targeted therapy for obesity-related pancreatic adenocarcinoma. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr B31.

Abstract B66: Novel adjuvant therapy for obesity-related cancers

Obesity incidence has reached alarming levels, particularly in minority populations: African American (AA) and Latinos. The risk of develop several cancers (i.e., breast, pancreatic and endometrial cancers) is strongly correlated to obesity. One of the essential factors involved in this relationship is leptin, the major adipokine secreted by adipose and tumor cells. Leptin is a mitogenic, proangiogenic, antiapoptotic and inflammatory factor that induces tumor growth and metastasis. Leptin has also been shown to increase cancer stem cell population and drug resistance in tumors. We have produced a potent and specific antagonist (LPrA2) that blocks leptin signaling and impairs its effects on cancer cells. LPrA2 conjugated to iron-oxide nanoparticles (IONP-LPrA2) shows enhanced bioavailability (half-life 8x higher) and inhibition effectiveness on leptin signaling in cancer cells. It is hypothesized that IONP-LPrA2 could serve as an adjuvant that increases effectiveness and allows the reduction of dosage of chemotherapeutic drugs, particularly in obesity contexts. Breast (E0771-TAM tamoxifen resistant, Py-8119, MDA-MB231, HCC1806 and MCF-7) and pancreatic cancer cells (Panc-1, BxPC-3, MiaPaca2), and their derived tumorspheres were treated with leptin, chemotherapeutics (Cisplatin, Doxorubicin, Paclitaxel and Gemcitabine) and IONP-LPrA2. Additionally, E0771-TAM and Py-8119 cells, and MDA-MB231 and Panc-1 tumorspheres were inoculated in C57BL/6J female mice (obese and lean) and female and male CD1 nu/nu mice. The mice were treated with IONP-LPrA2 during 4 weeks. Leptin induced proliferation and cell cycle progression in all cancer cells tested. Leptin also increased the number and size of breast and pancreatic cancer tumorspheres, and the levels of cancer stem cell (ALDH1, CD44, CD24, ESA), and chemoresistant (ABCB1) and pluripotent (NANOG) markers. IONP-LPrA2 treatment increased the effects of chemotherapeutics on cancer cells, and delayed tumor onset and growth. These data suggest that leptin is a mitogenic factor that increases cancer aggressiveness and survival. IONP-LPrA2 is a promising chemotherapeutic adjuvant, especially for patients suffering from obesity-related cancers. Citation Format: Pierre Candelaria, Tia Harmon, Adriana Harbuzariu, Antonio Rampoldi, Crystal Lipsey, Mckay Mullen, Ann Kurian, Courtney Dill, Cynthia Tchio, Danielle Daley-Brown, Shakeyla Nunez, Viola Lanier, Ruben Rene Gonzalez-Perez. Novel adjuvant therapy for obesity-related cancers. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr B66.

Abstract 1026: PEG-LPrA2 is a non-toxic adjuvant for triple negative breast cancer

Background: Triple Negative Breast Cancer (TNBC) is an aggressive cancer with poor prognosis and is difficult to treat. Current standard therapy for the disease includes a combination of chemotherapeutic drugs: doxorubicin (DOX), paclitaxel (TAX), and cyclophosphamide (CTX). These drugs are ineffective as they exhibit shortcomings and several side effects. TNBC patients develop chemoresistance that may be enhanced by leptin, which affects survival, proliferation, and angiogenesis. Our lab developed and tested a novel and specific inhibitor of leptin signaling, LPrA2. A pegylated derivative of LPrA2 (PEG-LPrA2), with enhanced bioavailability, was successfully used in mouse breast cancer models. Preliminary data showed that PEG-LPrA2 was non-toxic in vitro. Therefore, it is hypothesized that PEG-LPrA2 is not toxic in vivo. Methods: To determine potential toxicity of PEG-LPrA2, in vitro and in vivo assays were performed. In vitro toxicity of PEG-LPrA2 was tested in a human non-malignant mammary epithelial cell line (MCF-10A). MCF-10A cells were cultured in 96 well plates (5,000 cells/ well) and grown to 70-80% confluence. Cells were treated with PEG-LPrA2 for 24 hrs and viability was determined via MTT assay. In vivo toxicity studies were performed in obese mice. Fifty-seven, eight week old C57BL/6J mice (Charles River Laboratories) were divided into 6 groups. Control mice were fed a low fat diet (10% Kcal from fat) and the rest of the mice were fed a high fat diet (60% Kcal from fat) for 11 weeks. Obesity was characterized as body weight (BW) ≥ 25% BW of control mice. Obese mice were divided into six groups (n = 7/each). Mice were injected with 50 μL of either Sc-PEG-LPrA2 (scramble control) or active inhibitor, PEG-LPrA2, (0.1 mM, 1 mM, or 5 mM) two times a week, for eight weeks. Blood chemistries were analyzed. Additionally, heart, liver, and kidney tissue were harvested and examined to determine toxicity. The tissues were probed for OB-R via immuno histochemistry. Results: The results showed no changes in BW or food intake. Additionally, no evident changes in blood parameters and organ histology were found. Conclusions: PEG-LPrA2 is non-toxic and could serve as an adjuvant therapy for standard TNBC chemotherapeutics. Citation Format: Courtney D. Dill, Adriana Harbuzariu, Antonio Rampoldi, Crystal C. Lipsey, Viola Lanier, Tia Harmon, Danielle Daley-Brown, Cynthia Tchio, Pierre Candelaria, Ruben Rene Gonzalez-Perez. PEG-LPrA2 is a non-toxic adjuvant for triple negative breast cancer. [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 1026.

Abstract 1901: Leptin modulation of PCSC, HDAC, and microRNA in pancreatic adenocarcinoma

Background: Obesity is an important risk factor of Pancreatic Adenocarcinoma (PA) and it is characterized by the accumulation of excessive body fat and a Body Mass Index (BMI) value greater than 30. Obesity is also characterized by high levels of leptin, which has been consistently associated with the development of many different cancer including PA. Leptin can induce the proliferation of Pancreatic Cancer Stem Cells (PCSC), which are responsible for chemoresistance, invasiveness and reoccurrence of PA. PCSC express specific cell markers and can form tumorspheres in vitro. Obesity can alter the DNA acetylation and microRNA activity which are also linked to PA progression. We hypothesized that high level of leptin could modulate Histone Deacetylase (HDAC) and microRNA activity in PA cells, which induce PCSC changes and tumor progression. Methods: The PA cell lines were cultured in mammocult media that contained heparin and hydrocortisone, which will allow the proliferation of tumorspheres enriched with PCSCs. The cells were cultured with leptin, chemotherapeutic drug, and leptin signaling inhibitor IONP-LPrA2. Tumorspheres formation (number and size) was determined after 1 week of treatment. Additionally, the levels of PCSC markers, HDAC1, HDAC2, HDAC3, and HDAC8 in tumorspheres were determined using flow cytometry, western blot, and RT-PCR. In addition, the effects of treatments on miR21 and miR200a/c levels were determined using RT-PCR. Results: Leptin induced PA tumorspheres formation and size, which was accompanied by higher level of PCSC markers (CD24, CD44, ESA, and ALDH1). Moreover, leptin affected the level of HDACs, miR21 and miR200a/c in PA tumorspheres. IONP-LPrA2 abrogated leptin effects and decreased PCSC which were spared by chemotherapeutics. Conclusion: Obesity signals via leptin could be involved in the increase PA aggressiveness and chemoresistance, which may be linked to the increase of PCSC. Leptin could induce PA progression and chemoresistance via modulation of HDAC and miRNA. Acknowledgement: This work was supported by the DOD W81XWH-13-1-0382; NIH/SBIR1R41CA183399-01A1; Pilot Project Award from MSM/Tuskegee University/UAB Cancer Center Partnership grant 5U54CA118638; PC SPORE Grant from UAB to RRGP; Calvin Johnson Jr. Foundation Pancreatic Cancer Research Scholarship to CITM, and facility and support services at Morehouse School of Medicine (1G12RR026250-03; NIH RR03034 and 1C06 RR18386). Citation Format: Cynthia M. Tchio, Adriana Harbuzariu, Tia Harmon, Derrick Beech, Ruben Gonzalez-Perez. Leptin modulation of PCSC, HDAC, and microRNA in pancreatic adenocarcinoma. [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 1901.

Abstract 1006: Novel adjuvants in triple negative breast cancer chemotherapy

Background: Obese patients develop more frequently triple negative breast cancer (TNBC) that has not target therapy and are commonly treated with chemotherapeutics. Leptin, whose levels are elevated in obesity, can induce TNBC proliferation, angiogenesis and resistance to chemotherapeutics. An antagonist for leptin receptor OB-R, leptin peptide receptor antagonist 2 (LPrA2), has been shown to block leptin signaling and decrease tumor progression. LPrA2 also countervails leptin induced resistance to chemotherapeutic agents. We used pegylation or iron oxide nanoparticle (IONPs) as adjuvants to increase LPrA2 solubility, stability and effectiveness. Hypothesis: Conjugated LPrA2 will decrease TNBC cells proliferation, expression of leptin target molecules and tumorigenesis. Methods: Human TNBC and murine breast adenocarcinoma derived cell line E0771 (progesterone and HER2 receptor negative) were used. The E0771 cell line was generated from an estrogen receptor positive (ER+) mammary adenocarcinoma isolated from a C57BL/6J mouse. E0771 was made insensitive to estrogen by treatment with drug Tamoxifen (TAM) mimicking TNBC. To specifically assess the role of RBP-Jk (CBS/CSL, an essential transcription factor for Notch signaling) the CRISPR/Cas9 system was used to disrupt RBP-JK gene expression in both wild-type and TAM treated E0771 cells. Cells were treated with chemotherapeutics (Paclitaxel, Doxorubicine, Ciclophosphamide) in presence of leptin and LPrA2-conjugates. The expression of leptin-targeted molecules, Breast Cancer Stem Cells (BCSC) and EMT markers were analyzed after cell treatment. Results: Chemotherapeutics effects on proliferation, survival and molecular markers were modified by the addition of LPrA2-conjugates. Notch molecules (receptors and ligands) were downregulated by LPrA2 treatment. Conclusion: The current data indicate that Leptin inhibition could be used as an adjuvant for chemotherapeutic treatments in TNBC patients. LPrA2-conjugates could increase the efficacy of chemotherapy. Acknowledgements: This work was partially supported by the National Institute of Health and National Cancer Institute Grant U54 CA118638, NIH/SBIR 1R41CA183399-01A1, and DOD Idea Award BC W81XWH-13-1-0382 to RRGP; and facilities, and support services at Morehouse School of Medicine (NIH RR03034 and 1C06 RR18386) and NIH/NCRR grant 1G12RR026250-03. Citation Format: Antonio Rampoldi, Adriana Harbuzariu, Tia L. Harmon, Ruben R. Gonzalez-Perez. Novel adjuvants in triple negative breast cancer chemotherapy. [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 1006.