Immune evasion by tumors includes several different mechanisms, including the inefficiency of antigen presenting cells (APCs) to trigger anti-tumor T cell responses. B lymphocytes may display a pro-tumoral role but can also be modulated to function as antigen presenting cells to T lymphocytes, capable of triggering anti-cancer immune responses. While dendritic cells, DCs, are the best APC population to activate naive T cells, DCs or their precursors, monocytes, are frequently modulated by tumors, displaying a tolerogenic phenotype in cancer patients. In patients with cervical cancer, we observed that monocyte derived DCs are tolerogenic, inhibiting allogeneic T cell activation compared to the same population obtained from patients with precursor lesions or cervicitis. In this work, we show that B lymphocytes from cervical cancer patients respond to treatment with sCD40L and IL-4 by increasing the CD80+CD86+ population, therefore potentially increasing their ability to activate T cells. To test if B lymphocytes could actually trigger anti-tumor T cell responses, we designed an experimental model where we harvested T and B lymphocytes, or dendritic cells, from tumor bearing donors, and after APC stimulation, transplanted them, together with T cells into RAG1-/- recipients, previously injected with tumor cells. We were able to show that anti-CD40 activated B lymphocytes could trigger secondary T cell responses, dependent on MHC-II expression. Moreover, we showed that dendritic cells were resistant to the anti-CD40 treatment and unable to stimulate anti-tumor responses. In summary, our results suggest that B lymphocytes may be used as a tool for immunotherapy against cancer.

PURPOSE:To compare the inflammatory response of three different meshes on abdominal hernia repair in an experimental model of incisional hernia. METHODS:Median fascial incision and skin synthesis was performed on 30 Wistar rats. After 21 days, abdominal hernia developed was corrected as follows: 1) No mesh; 2) Polypropylene mesh; and, 3) Ultrapro ® mesh. After 21 days, the mesh and surrounding tissue were submitted to macroscopic (presence of adhesions, mesh retraction), microscopic analysis to identify and quantify the inflammatory and fibrotic response using a score based on a predefined scale of 0-3 degrees, evaluating infiltration of macrophages, giant cells, neutrophils and lymphocytes. RESULTS:No significant difference was seen among groups in adherences, fibrosis, giant cells, macrophages, neutrophils or lymphocytes (p>0.05). Mesh shrinkage was observed in all groups, but also no difference was observed between polypropylene and Ultrapro mesh (7.0±9.9 vs. 7.4±10.1, respectively, p=0.967). Post-operatory complications included fistula, abscess, dehiscence, serohematic collection and reherniation, but with no difference among groups (p=0.363). CONCLUSION:There is no difference between polypropylene (high-density) and Ultrapro ® (low-density) meshes at 21 days after surgery in extraperitoneal use in rats, comparing inflammatory response, mesh shortening, adhesions or complications.

Chronic signaling by molecules generated in the tumor microenvironment has local and systemic effects on the immune system. We have previously shown that cervical cancer cells express cytokines as IL-6 and G-CSF, among other factors. These cytokines have been associated with cancer progression in several types of cancer, either by promoting chronic inflammation and/or tolerance. Trying to better understand how cells from the immune system and tumor integrate signals generated by the tumor microenvironment, we have investigated the activation status of signaling pathways involved in cell proliferation and survival, inflammation and immune responses. We observed a cohort of cervical cancer patients, all of whom had cervical biopsies positive for high oncogenic risk human papillomavirus (HPV). In the cervical cancer biopsies, we found constitutive expression of phosphorylated STAT3, Akt, p65 NFκB and CREB, in both the tumor and leukocyte compartments. In the peripheral blood, however, we found constitutive expression of phosphorylated STAT3 and Akt, but significantly lower expression of phosphorylated p65 NFκB than in controls. Data previously published by our laboratory using a HPV16 experimental model showed high constitutive expression of phospho-STAT3 and low negative expression of phospho-p65 NFκB in splenocytes of tumor-bearing mice compared to controls. Given the data from our patients, we hypothesized that the high STAT3 expression and low NFκB expression could have a correlation, with a biologic effect on tumor-bearing subjects. Again, using an HPV16 experimental model, we neutralized IL-6 and G-CSF expression or pharmacologically inhibited STAT3 with the NSC74859 compound. In both cases, we observed significant reduction in tumor growth, decrease in phospho-STAT3 expression (when using the neutralizing antibodies), and importantly, significant increase in phospho-p65 NFκB expression. We also observed a significant increase in T-cell infiltration in tumors from treated animals and increase in antigen-specific T-cell proliferation. Our data indicate that cytokines that signal chronically through STAT3 can inhibit antitumor immune responses through NFκB inhibition. We also suggest that inhibition of STAT3 may be used as therapeutic tool against cervical cancer and other HPV-associated cancers. Financial support: FAPESP 2014/19326-6; 2008/57889-1; CNPq 573799/2008-3. Citation Format: Renata Ariza Marques Rossetti, Gretel Rodriguez Rodriguez, Ildelfonso Alves Da Silva, Jr. Jesus De Paula Carvalho, Maria Beatriz Sartor De Faria Rosa, Luisa Lina Villa, Ana Paula Lepique. Cervical cancer immunomodulation through stat3 and p65 NFκb: Effects beyond the tumor microenvironment [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr A22.