Research Basic Science and Translational Research is being conducted both individually and collaboratively by the members of the NYPOG to better understand how the tumor microenvironment affects disease progression and how therapies currently used to treat cancer affect the tumor microenvironment. NYPOG assists in these efforts by providing expertise in the areas of research outlined below: Dissemination Cancer cells within the tumor microenvironment are known to be genotypically and phenotypically heterogenous. Only a minority of cells can migrate across the endothelial barrier of the vasculature within the primary tumor; one of the first steps in the metastatic cascade. NYPOG researchers determined that the actin regulatory protein MenaINV is required for transendothelial migration of breast cancer cells (Pignatelli et al, 2014) and identified intravasation portals, called TMEM doorways, for hematogenous breast cancer cell dissemination to distant sites (Harney et al, 2015, NIH Director’s blog). NYPOG researchers also determined the phenotype of cancer cells that facilitates MenaINV-mediated invasion and dissemination called MenaCalc. Both TMEM doorways (Rohan et al, 2014, and Sparano et al, 2017) and MenaCalc (Agarwal et al, 2012, and Forse et al, 2015) are clinically validated biomarkers of metastasis. Stemness Successful colonization of distant sites, i.e. onset of proliferation of cancer cells and development of metastatic foci, requires the activation of a stem phenotype in tumor cells. A high proportion of cancer stem cells (CSCs) in primary tumors is associated with poor prognosis and increased metastatic relapse. CSCs have an enhanced ability to self-renew which makes them uniquely capable of initiating and sustaining primary and metastatic tumor growth. Importantly CSCs are intrinsically more therapy-resistant than their more differentiated progeny. NYPOG researchers determined that macrophages (immune cells within the tumor microenvironment) can induce non-stem cancer cells to become stem. NYPOG researchers are evaluating the behavior of CSCs in vivo and are translating their observation to human tissue samples obtained from patients to determine if CSC density can be used to give better a prognosis regarding disease outcome or to predict response to chemotherapy. Dormancy An important concept in cancer biology and cancer outcome is the ability of disseminated cells to remain dormant for many years before they initiate proliferation. Indeed, some types of breast cancer are notorious for late relapse, which can occur even 25 years after the initial diagnosis. It is important to better understand factors that regulate dormancy and determine if this knowledge can be used for prognostication and evaluation of treatment options. We are making progress in understanding the role of tumor microenvironment in regulating dormancy and its effect on metastasis (Linde et al, 2016; Harper et al, 2106) Heath Disparities It is well known that some cancers behave more aggressively in patients of certain racial and ethnic backgrounds. For example, black patients with breast and prostate cancer, compared to other races, have lower overall survival. The reasons for these disparities are still not clear. Until recently, it was thought that disparities in access to care, socioeconomic factors, and education were the root cause of higher morbidity in certain racial groups. However, it is now clear that biological factors play a major role cancer progression and response to therapy. These biological factors could also affect the response to chemotherapy. Indeed, we have preliminary evidence that black, compared to non-black, patients have worse distant recurrence-free survival when treated with pre-operative (neoadjuvant) chemotherapy (Pastoriza et al, 2018). NYPOG studies aim to determine to what extent the tumor microenvironment is responsible for racial disparity in cancer outcome (Kim et al, 2020). Biomarker Development The ability to determine disease outcome and predict response to treatment depends on the availability of robust biomarkers. There are many biomarkers associated with cancer proliferation. However, markers that can predict cancer cell dissemination are lacking. Since ~90% of cancer related mortality is due to metastatic disease, and metastatic disease depends on the ability of cancer cells to travel to distant organs, developing markers that can distinguish metastatic from non-metastatic cancers, and responsive cancers from those resistant to chemotherapy, is critical. NYPOG researchers are currently focused on evaluating their published markers of dissemination (Sparano et al, 2017, Entenberg et al, 2020) in multi-ethnic cohorts. Interestingly, certain subsets of patients have been found to have an increased TMEM-doorway density and MenaINV expression in residual tumor after chemotherapy, a previously unrecognized form of chemotherapy resistance (Karagiannis et al, 2017) that needs to be evaluated further to determine if some races are more prone than others to this type of resistance. We aim to combine basic science insights and advanced digital pathology technologies to distinguish which patients are likely to develop metastases and respond well to chemotherapy. Retrospective Breast and Pancreatic Cancer Working Group Currently, NYPOG research is organized around working groups that either retrospectively analyze archival tissues or evaluate the disseminating tumor microenvironment in real time. The retrospective cancer working groups use formalin-fixed paraffin-embedded (FFPE) breast cancer tissue samples from patients to define the critical pro-metastatic features within the breast tumor microenvironment that are associated with distant recurrence. This focus is aligned with the mission, vision, goals, and objectives of NYPOG. Retrospective Breast Cancer Working Group The following major projects are currently on-going: The evaluation of the relationship between race and the prognostic tumor microenvironment of metastasis biomarkers (TMEM, MenaCalc, MenaINV, combined TMEMMenaCalc and TMEMMenaINV) using primary breast cancer samples from patients with stage I-III breast cancer treated with standard adjuvant therapy. The comparison of pro-metastatic tumor microenvironment (TMEM, MenaCalc, MenaINV, combined TMEMMenaCalc and TMEMMenaINV, stem markers such as Sox9, and dormancy markers such as NR2F1) in residual cancer after NAC, between black and non-black patients, and association of these markers with recurrence. The development of an IHC assay for visualization of active TMEM doorways (i.e. doorways that are open at the time of tissue fixation). The development of automated image analysis algorithms for biomarker evaluation. Retrospective Pancreatic Cancer Working Group The following major projects are currently on-going: Identification of TMEM-doorways in pancreatic ductal adenocarcinoma (PDAC) in patient samples and pre-clinical models of PDAC. Correlation of TMEM-doorways with distant recurrence in PDAC. Adaptation of the active TMEM staining assay to PDAC. Evaluation of TMEM-function in real time We are currently evaluating if TMEM function can be determined using minimally invasive approaches such as standard gadolinium-based MRI. These studies are being performed in pre-clinical models of breast cancer and in patients.