Tunneling nanotubes (TnTs) represent a novel mechanism by which intercellular components such as proteins, Golgi vesicles, and mitochondria can be transferred from cell to cell in the complex tumor microenvironment. Here, we report data showing that microRNAs (miRNAs) are transferred through TnTs in osteosarcoma and ovarian cancer as in vitro model systems. miRNA array analysis demonstrated significant upregulation of miR-19a in osteosarcoma tumors resected from human patients, and differential expression of miR-199a in ovarian cancer cell lines resistant or sensitive to platinum chemotherapy. K7M2 murine osteosarcoma cells were transfected with miR-19a and cultured with non-transfected K7M2 cells in low-serum, hyperglycemic medium for up to 72 hours to induce TnT formation. miRNA transfer via TnTs was detected by time-lapse microscopic imaging. miR-19 was also transported via TnTs connecting transfected K7M2 cells and non-transfected stromal MC3T3 murine osteoblast cells. Similar findings were observed in studies of TnT-mediated transport of miR-199a among SKOV3 ovarian cancer cells and non-malignant IOSE human ovarian epithelial cells. To quantify TnT-mediated transport of miRNAs, we used modified Boyden chambers to separate miR19a-transfected K7M2 cells (top chamber) and DiI-labeled MC3TC cells (bottom chamber) as compared to open culture of these cells. FACS analysis of cells collected after 48-hours of culture indicated that miR19a-positive MC3TC cells was 3-fold higher in open culture; this finding suggest that miR-19a occurred via TnTs, exclusive of other forms of cell-cell communication. These studies demonstrate that TnTs mediate direct transfer of genetic material between tumor and stromal cells.

Community-based participatory research (CBPR) and community-engaged research have been established in the past 25 years as valued research approaches within health education, public health, and other health and social sciences for their effectiveness in reducing inequities. While early literature focused on partnering principles and processes, within the past decade, individual studies, as well as systematic reviews, have increasingly documented outcomes in community support and empowerment, sustained partnerships, healthier behaviors, policy changes, and health improvements. Despite enhanced focus on research and health outcomes, the science lags behind the practice. CBPR partnering pathways that result in outcomes remain little understood, with few studies documenting best practices. Since 2006, the University of New Mexico Center for Participatory Research with the University of Washington’s Indigenous Wellness Research Institute and partners across the country has engaged in targeted investigations to fill this gap in the science. Our inquiry, spanning three stages of National Institutes of Health funding, has sought to identify which partnering practices, under which contexts and conditions, have capacity to contribute to health, research, and community outcomes. This article presents the research design of our current grant, Engage for Equity, including its history, social justice principles, theoretical bases, measures, intervention tools and resources, and preliminary findings about collective empowerment as our middle range theory of change. We end with lessons learned and recommendations for partnerships to engage in collective reflexive practice to strengthen internal power-sharing and capacity to reach health and social equity outcomes.

In this study, we demonstrated that hypoxic conditions stimulated an increase in tunneling nanotube (TNT) formation in chemoresistant ovarian cancer cells (SKOV3, C200). We found that suppressing the mTOR pathway using either everolimus or metformin led to suppression of TNT formation in vitro, verifying TNTs as a potential target for cancer-directed therapy. Additionally, TNT formation was detected in co-cultures including between platinum-resistant SKOV3 cells, between SKOV3 cells and platinum-chemosensitive A2780 cells, and between SKOV3 cells cultured with benign ovarian epithelial (IOSE) cells; these findings indicate that TNTs are novel conduits for malignant cell interactions and tumor cell interactions with other cells in the microenvironment. When chemoresistant C200 and parent chemosensitive A2780 cells were co-cultured, chemoresistant cells displayed a higher likelihood of TNT formation to each other than to chemosensitive malignant or benign epithelial cells. Hypoxia-induced TNT formation represents a potential mechanism for intercellular communication in ovarian cancer and other forms of invasive refractory cancers.

Intercellular communication plays a critical role in the ever-evolving landscape of invasive cancers. Recent studies have elucidated the potential role of tunneling nanotubes (TNTs) in this function. TNTs are long, filamentous, actin-based cell protrusions that mediate direct cell-to-cell communication between malignant cells. In this study, we investigated the formation of TNTs in response to variable concentrations of the chemotherapeutic drug doxorubicin, which is used extensively in the treatment of cancer patients. Doxorubicin stimulated an increased formation of TNTs in pancreatic cancer cells, and this occurred in a dose-dependent fashion. Furthermore, TNTs facilitated the intercellular redistribution of this drug between connected cells in both pancreatic and ovarian cancer systems in vitro. To provide supportive evidence for the relevance of TNTs in pancreatic cancer in vivo, we performed multiphoton fluorescence microscopy and imaged TNTs in tumor specimens resected from three human patients with pancreatic adenocarcinoma, and one with neuroendocrine carcinoma. In sum, TNT formation was upregulated in aggressive forms of pancreatic carcinoma, was further stimulated after chemotherapy exposure, and acted as a novel method for drug efflux. These findings implicate TNTs as a potential novel mechanism of drug resistance in chemorefractory forms of cancer.

Objectives To determine the frequency of multiple type cervical HPV infections, and whether any types are involved in multiple type infections more or less frequently than might be expected if these infections occur randomly. Methods In this retrospective analysis of type-specific HPV testing, results from women 18-65 years old with samples collected between July 2007 and May 2011 were considered. Multivariate logistic regression analysis was used to model the presence of each of the 24 most prevalent HPV types, adjusting for one other HPV type, age, laboratory region, and age by region interactions. Results HPV infection was present in 74,543 of 309,471 women (24.1%) and 65,492 (21.1%) were positive for one of the top 24 most prevalent HPV types. The most common HPV type was HPV type 16, occurring in 4.1 of the entire sample%. 14,181 women were positive for 2 or more HPV types (4.6% of entire sample, 19.0% of HPV positive sample). Two-way HPV type comparisons were analyzed. Types 52, 53, 81, and 83 more likely to occur in multiple infections with other types, and types 16, 58, and 66 were less likely to occur in multiple infections with other types. HPV types 72 and 81 have the strongest positive relationship (OR=5.2, 95% CI: 3.6, 7.4). HPV types 33 and 66 have the strongest negative relationship (OR 0.4, 95% CI: 0.2, 0.6). Conclusions In this population, multiple type HPV infections were present in 4.6% of all women. Our findings suggest that there may be both competitive and cooperative interactions between HPV types.