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Our earlier studies reported a unique potentiated combination (TriCurin) of curcumin (C) with two other polyphenols. The TriCurin-associated C displays an IC50 in the low micromolar range for cultured HPV+ TC-1 cells. In contrast, because of rapid degradation in vivo, the TriCurin-associated C reaches only low nano-molar concentrations in the plasma, which are sub-lethal to tumor cells. Yet, injected TriCurin causes a dramatic suppression of tumors in TC-1 cell-implanted mice (TC-1 mice) and xenografts of Head and Neck Squamous Cell Carcinoma (HNSCC) cells in nude/nude mice. Here, we use the TC-1 mice to test our hypothesis that a major part of the anti-tumor activity of TriCurin is evoked by innate and adaptive immune responses. TriCurin injection repolarized arginase1high (ARG1high), IL10high, inducible nitric oxide synthaselow (iNOSlow), IL12low M2-type tumor-associated macrophages (TAM) into ARG1low, IL10low, iNOShigh, and IL12high M1-type TAM in HPV+ tumors. The M1 TAM displayed sharply suppressed STAT3 and induced STAT1 and NF-kB(p65). STAT1 and NF-kB(p65) function synergistically to induce iNOS and IL12 transcription. Neutralizing IL12 signaling with an IL12 antibody abrogated TriCurin-induced intra-tumor entry of activated natural killer (NK) cells and Cytotoxic T lymphocytes (CTL), thereby confirming that IL12 triggers recruitment of NK cells and CTL. These activated NK cells and CTL join the M1 TAM to elicit apoptosis of the E6+ tumor cells. Corroboratively, neutralizing IL12 signaling partially reversed this TriCurin-mediated apoptosis. Thus, injected TriCurin elicits an M2→M1 switch in TAM, accompanied by IL12-dependent intra-tumor recruitment of NK cells and CTL and elimination of cancer cells.

// Sumit Mukherjee 1, 3, 5, * , Priya Ranjan Debata 5, 8, * , Rahman Hussaini 5 , Kaushiki Chatterjee 2, 4 , Juliet N.E. Baidoo 1, 3 , Samay Sampat 5 , Anita Szerszen 6 , Joseph P. Navarra 7 , Jimmie Fata 2 , Elena Severinova 6, 9 , Probal Banerjee 1, 5 and Mario R. Castellanos 6 1 Department of Chemistry, The College of Staten Island (CUNY), New York, NY, USA 2 CUNY Doctoral Program in Biology, CUNY Graduate Center, New York, NY, USA 3 CUNY Doctoral Program In Biochemistry, CUNY Graduate Center, New York, NY, USA 4 Department of Biology, The College of Staten Island (CUNY), New York, NY, USA 5 Center of Developmental Neuroscience, The College of Staten Island (CUNY), New York, NY, USA 6 Division of Research, Department of Medicine, Staten Island University Hospital (Northwell Health), New York, NY, USA 7 College of Pharmacy and Health Sciences, St. John’s University, New York, NY, USA 8 Current Address: Department of Zoology North Orissa University Baripada, Mayurbhanj, Odisha, India 9 Current Address: Cell Biology and Molecular Medicine, Rutgers University, Newark, NJ, USA * These authors contributed equally to this work Correspondence to: Probal Banerjee, email: probal.banerjee@csi.cuny.edu , probalbanerjee@yahoo.com Keywords: curcumin, cervical cancer, human papillomavirus, synergism, combination index Received: May 31, 2016 Accepted: September 02, 2016 Published: March 29, 2017 ABSTRACT Curcumin (from curry) (C) is highly potent against cervical cancer cells (CCC), but poor bioavailability has limited its clinical use. Similar natural polyphenols resveratrol (from grapes) (R), and epicatechin gallate (from green tea) (E) also display activity against CCC. By treating CCC (HeLa) with C, E, or R, or combinations of these compounds, we computed combination indices and observed a strong synergism among C, E, and R at the unique molar ratio 4:1:12.5. This combination, named as TriCurin, rapidly down regulated HPV18 E6 and NF-kB expression while concomitantly inducing the tumor suppressor protein p53 in HeLa cells. In the mouse c-Ha-ras and HPV16 E6, E7-expressing TC-1 CCC, both C and TriCurin elicited suppression of E6, induction of both p53 and acetyl-p53 (activated p53), and activation of caspase-3, but the TriCurin-evoked changes were several-fold greater than that produced by curcumin (4.7-fold for E6 inhibition, and 2-fold, 6-fold, and 1.7-fold for the induction of p53, acetyl-p53, and active caspase-3, respectively). Consequently, TriCurin was more potent in killing TC-1 and HeLa cells. Intralesional TriCurin treatment of tumors generated in mice by subcutaneously implanting the TC-1 CCC caused an 80–90% decrease in tumor growth. The ability of C to eliminate HeLa cells was significantly stabilized when delivered as TriCurin than when delivered alone. Topical application of TriCurin dispersed in a cream base afforded efficient transfer of C across the skin. Subcutaneous TriCurin injection yielded no adverse effect in tumor-naive healthy mice. Thus, TriCurin is a safe and promising therapeutic agent against HPV-associated disease.

Glioblastoma (GBM) is the most insidious form of primary adult brain tumor with a mean life expectancy of 12-24 months. Previously, we have used the non-invasive strategies of (1) intranasal delivery of a glioblastoma-directed curcumin (CC) adduct (CC-CD68Ab) and (2) the intraperitoneal (i.p.) infusion of a lipid-encapsulated formulation of CC-phytosome to rescue orthotopically GL261-implanted GBM mice and study the effect of CC on the phenotype of the tumor-associated microglial cells (TAMs). Both treatment regimens not only caused tumor remission in 50-60% of GL261-implanted GBM mice, but also induced a dramatic change in the tumor-associated Iba1+ TAMs, suppressing the tumor-promoting Arginase1high, IL10high, iNOSlow, IL12low M2-type TAMs, while simultaneously inducing the Arginase1low, IL10low, iNOShigh, IL12high M1-type TAMs. Concurrently, we observed a marked induction and phosphorylation-mediated activation of microglial p65 NF-kB and STAT1, with concomitant suppression and inactivation of STAT3. p-STAT1high, p-STAT3low M1 microglia are known to cause IL12-dependent recruitment/activation of tumoricidal NKp46high natural killer (NK) cells. In determining the kinetics of CC-induced M1 repolarization of M2-TAMs, we observed that five days of CCP treatment (i.p.) was sufficient to induce a dramatic change in the tumor-associated Iba1+ TAMs, inhibiting the tumor-promoting M2-type TAM population, while activating M1-type microglia. As expected, we observed a concomitant recruitment of NKp46high NK cells into the GBM tumor. Cognizant of the fact that NK cells activate and stabilize the M1-microglia, we eliminated the NK cells in these GBM mice using the NK cell-targeted antibody NK1.1 Ab to observe a significant reduction in CC-evoked repolarization of TAMs. Our results demonstrate a unique oncoimmunotherapeutic function of CC, which when appropriately delivered, not only eliminates GBM directly, but also indirectly elicits recruitment and activation of tumoricidal NK cells and M1-TAMs. Furthermore, maintenance of this CC-evoked M1 phenotype is contingent upon CC-induced recruitment and activation of NK cells. Thus, when delivered appropriately, CC functions on GBM both directly as well as by stimulating and recruiting an army of immune cells that eliminate both GBM and GBM-initiating cells. Citation Format: Sumit Mukherjee, Angela Fried, Rahman Hussaini, Richard White, Aheli Chatterjee, Probal Banerjee. Appropriately delivered curcumin causes recruitment of natural killer cells into glioblastoma brain, stabilizing M1 polarization of tumor-associated microglia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4577. doi:10.1158/1538-7445.AM2017-4577