Contemporary treatment of keloids: A 10-year institutional experience with medical management, surgical excision, and radiation therapy

INTRODUCTION

We evaluate a single center's, decade-long experience utilizing 3 approaches to keloid treatment: corticosteroid medical management (MM), surgical excision (SE), and surgical excision + radiation therapy (SE + RT).

STUDY DESIGN

Patients undergoing keloid treatment were identified (2008-2017). Outcomes were symptomatology/cosmesis for MM, and recurrence and complications for SE and SE + RT. Logistic regression was used to determine factors associated with recurrence and complications.

RESULTS

284 keloids (95 MM, 94 SE, 95 S E + RT) corresponded to patients with a median age of 39.1 (IQR: 26.1-53), 68.1% Black, and followed-up for 15.4 months (IQR: 5.6-30.7). For MM, 84.6% and 72.5% reported improvement in cosmesis and symptoms, respectively. SE and SE + RT recurrence were 37.2 and 37.9%, respectively. In adjusted analyses, higher radiation doses were associated with decreased recurrence whereas male gender (OR 3.3) and postoperative steroids (OR 9.5) were associated with increased recurrence (p < 0.01). There were more complications in the SE + RT group.

CONCLUSIONS

MM resulted in at least some improvement. Recurrence rates after SE and SE + RT were similar. Female sex is protective, race does not affect outcomes.

Abstract B42: The sigma-2 receptor as a target for therapeutic drug delivery in triple negative breast cancer

Introduction: Triple Negative Breast Cancer (TNBC) is an aggressive form of breast cancer and typically results in poor patient prognosis. While other breast cancer subtypes benefit from targeted therapies, TNBC currently has no approved agents. The sigma-2 receptor has been validated as a proliferation marker and also a site for therapeutic drug delivery in ovarian and pancreatic cancer. In this study we evaluated the sigma-2 receptor as a target for therapeutic drug delivery in TNBC using a sigma-2 targeting vehicle conjugated to a small molecule activator of caspases(SMAC) mimetic, SW-IV-134.

Methods: Triple negative breast cancer cell lines; MDA-MB-231, HCC1937 and HCC1806 were tested for sensitivity to sigma-2 targeted compound SW-IV-134 vs. Taxol or the deconstructed conjugate subparts. 2 hr and 48 hr treatments we assessed to determine whether there was a significant in vitro targeting effect. Sigma-2 expression was quantified through radioligand saturation studies using cell homogenate tissue and the Ki value of SW-IV-134 for the sigma-2 receptor was calculated through competitive inhibition studies. Caspase 3/7 activation was assessed after 2 or 48 hr treatments.

Results: SW-IV-134 was the most potent treatment in MDA-MB-231 and HCC1937, while no difference from taxol was found in HCC1806. Sigma-2 receptor expression was found to be the highest in the MDA-MB-231 and no difference was found in HCC1937 and HCC1806. The Ki of SW-IV-134 for the sigma-2 receptor was 23 nM and is consistent with previously reported values. Caspase 3/7 activation was detected in all cell lines following treatment at 2 and 48 hr. The greatest caspase 3/7 activation was observed in the MDA-MB-231 cell line.

Conclusion: The sigma-2 receptor is expressed at different levels on the three TNBC cell lines and the receptor expression corresponds to therapeutic efficacy. SW-IV-134 was the most potent therapeutic tested in two of the three cell lines with no difference between taxol observed in HCC1806. This study shows the sigma-2 receptor is a target that can be exploited for therapeutic drug delivery in three TNBC cell lines and may provide a platform for future targeted therapy development for TNBC.

Citation Format: Mehran Makvandi, Estifanos D. Tilahun, Brian P. Lieberman, Kuiying Xu, Chenbo Zeng, Catherine Hou, Robert H. Mach. The sigma-2 receptor as a target for therapeutic drug delivery in triple negative breast cancer. [abstract]. In: Proceedings of the Fourth AACR International Conference on Frontiers in Basic Cancer Research; 2015 Oct 23-26; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2016;76(3 Suppl):Abstract nr B42.

The sigma-2 receptor as a therapeutic target for drug delivery in triple negative breast cancer

BACKGROUND

Triple-negative breast cancer (TNBC) is associated with high relapse rates and increased mortality when compared with other breast cancer subtypes. In contrast to receptor positive breast cancers, there are no approved targeted therapies for TNBC. Identifying biomarkers for TNBC is of high importance for the advancement of patient care. The sigma-2 receptor has been shown to be overexpressed in triple negative breast cancer in vivo and has been characterized as a marker of proliferation. The aim of the present study was to define the sigma-2 receptor as a target for therapeutic drug delivery and biomarker in TNBC.

METHODS

Three TNBC cell lines were evaluated: MDA-MB-231, HCC1937 and HCC1806. Sigma-2 compounds were tested for pharmacological properties specific to the sigma-2 receptor through competitive inhibition assays. Sigma-2 receptor expression was measured through radioligand receptor saturation studies. Drug sensitivity for taxol was compared to a sigma-2 targeting compound conjugated to a cytotoxic payload, SW IV-134. Cell viability was assessed after treatments for 2 or 48 h. Sigma-2 blockade was assessed to define sigma-2 mediated cytotoxicity of SW IV-134. Caspase 3/7 activation induced by SW IV-134 was measured at corresponding treatment time points.

RESULTS

SW IV-134 was the most potent compound tested in two of the three cell lines and was similarly effective in all three. MDA-MB-231 displayed a statistically significant higher sigma-2 receptor expression and also was the most sensitive cell line evaluated to SW IV-134.

CONCLUSION

Targeting the sigma-2 receptor with a cytotoxic payload was effective in all the three cell lines evaluated and provides the proof of concept for future development of a therapeutic platform for the treatment of TNBC.