October as Breast Cancer Conquering Month

October is breast cancer month, and for good reason. Despite the numerous races for the cure, fundraisers, and amusingly-titled motorcycle rides, breast cancer remains the number two killer of women, with over 30,000 women dying every year (Landis et al. 2013). The question is, why do women keep dying from breast cancer with all of the awareness and treatment options out there? The problem arises when we look at the complexity that lies behind the simple diagnosis of breast cancer. Normally, breast cancer research is "graded" based on certain histological markers in the affected tissue. Grading ranges from grade one to grade three of tissue (Ivshina et al. 2006). Ultimately, though, most of these gradings can be broken down into several different subcategories. There are up to 264 markers that distinguish grade 1 tumors from grade 3 tumors, and grade 2 tumors can be broken down into two distinct subcategories (Ivshina et al. 2006). With this many different types of cancer, it is no wonder that breast cancer is complex. When the problem of metastasis are added in, breast cancer goes from complex to downright insane. Metastasized cancer may have different groupings of cells, with some being stem cells and dormant cells, that will make treatment more difficult (Marino et al. 2013). The cure for this complexity lies in personalized medicine. The development of personalized medicine offers several different benefits for breast cancer patient. For one, the advent of xenografts are incredibly helpful for studying metastatic breast cancer. A xenograft is the transplantation of tissue from one species into the tissue of another species for study. In the case of humans, most xenografts go into mouse tissue. Several advances have been made recently, including the use of increased immunosuppression in mice undergoing the transplantation (Landis et al. 2013). Breast tumors prove incredibly difficult to transplant, and this increased immunosuppression decreases the likelihood of host-graft rejection (Landis et al. 2013). In addition, more successes have been had recently with the transplantation of mesenchymal-type cells along with the tumor. The tumors that were transplanted with mesenchymal cells had increased tumor vasculature and increased estrogen receptor expression, factors which make breast cancer more likely to metastasize (Landis et al. 2013). Creating a more aggressive xenograft line enables the study of more aggressive cancers, which are typically the types that kill more women than their less aggressive counterparts. The obvious benefits of these studies are to investigate more therapies for aggressive, metastatic breast cancer. Metastatic cancer proves particularly difficult to treat because the characteristics of the tumor that has metastasized may be different from the base tumor, and each metastasis may differ from the others (Marino et al. 2013). The models allow for modeling of the reaction of that particular tumor type when it is exposed to different treatments (Zhang et al. 2013). The lines that are created are consistent in reaction, proteomic expression, and histologic characteristics with the tumors they are derived from (Zhang et al. 2013). Ultimately, modeling such as this is incredibly useful in determining the outcome of a particular treatment without exposing the patient to rounds of therapy that could potentially not prove useful. Hopefully, this research will allow more highly metastatic cancer to have more effective treatment options, and October can become a celebration of how far we have come in beating breast cancer. References: Ivshina AV, George J, Senko O, Mow B, Putti TC, Smeds J, Lindahl T, Pawitan Y, Hall P, Nordgren H, et al. 2006 Nov. Genetic reclassification of histologic grade delineates new clinical subtypes of breast cancer. Cancer Research. doi: 10.1158/0008-5472.CAN-05-4414 Landis MD, Lehmann BD, Pietenpol JA, Chang JC. 2013 Jan. Patient-derived breast tumor xenografts facilitating personalized cancer therapy. Breast Cancer Research. 15(201): 1-9. Marino N, Woditschka S, Reed LT, Nakayama J, Mayer M, Wetzel M, Steeg PS. 2013 Oct. Breast cancer metastasis: issues for the personalization of its prevention and treatment. The American Journal of Pathology. 183(4): 1084-1095. Zhang X, Claerhout S, Prat A, Dobrolecki L, Petrovic I, Lai Q, Landis M, Wiechmann L, Schiff R, Giuliano M, et al. 2013 Jun. A renewable tissue resource of phenotypically stable, biologically and ethnically diverse, patient-derived human breast cancer xenografts. Cancer Research. doi: 10.1158/0008-5472.CAN-12-4081