Deepthi Uppalapati

Angiotensin II type 2 receptor signaling significantly attenuates growth of murine pancreatic carcinoma grafts in syngeneic mice

BackgroundPancreatic cancer is one of the most aggressive human malignancies, with a very poor prognosis. To evaluate the effect of angiotensin II (Ang II) type 2 receptor (AT2) expression in the hosts body on the growth of pancreatic carcinoma, we have investigated the growth of mouse pancreatic ductal carcinoma grafts in syngeneic wild type and AT2 receptor-deficient (AT2-KO) mice.MethodsThe role of AT2 receptor-signaling in stromal cells on the growth of murine pancreatic carcinoma cells (PAN02) was studied using various in vitro and in vivo assays. In vivo cell proliferation, apoptosis, and vasculature in tumors were monitored by Ki-67 immunostaining, TUNEL assay, and von Willebrand factor immunostaining, respectively. In the co-culture study, cell proliferation was measured by MTT cell viability assay. All the data were analyzed using t-test and data were treated as significant when p < 0.05.ResultsOur results show that the growth of subcutaneously transplanted syngeneic xenografts of PAN02 cells, mouse pancreatic ductal carcinoma cells derived from the C57/BL6 strain, was significantly faster in AT2-KO mice compared to control wild type mice. Immunohistochemical analysis of tumor tissue revealed significantly more Ki-67 positive cells in xenografts grown in AT2-KO mice than in wild type mice. The index of apoptosis is slightly higher in wild type mice than in AT2-KO mice as evaluated by TUNEL assay. Tumor vasculature number was significantly higher in AT2-KO mice than in wild type mice. In vitro co-culture studies revealed that the growth of PAN02 cells was significantly decreased when grown with AT2 receptor gene transfected wild type and AT2-KO mouse-derived fibroblasts. Faster tumor growth in AT2-KO mice may be associated with higher VEGF production in stromal cells.ConclusionsThese results suggest that Ang II regulates the growth of pancreatic carcinoma cells through modulating functions of host stromal cells; Moreover, Ang II AT2 receptor signaling is a negative regulator in the growth of pancreatic carcinoma cells. These findings indicate that the AT2 receptor in stromal fibroblasts is a potentially important target for chemotherapy for pancreatic cancer.

Human Umbilical Cord Matrix Mesenchymal Stem Cells Suppress the Growth of Breast Cancer by Expression of Tumor Suppressor Genes

Human and rat umbilical cord matrix mesenchymal stem cells (UCMSC) possess the ability to control the growth of breast carcinoma cells. Comparative analyses of two types of UCMSC suggest that rat UCMSC-dependent growth regulation is significantly stronger than that of human UCMSC. Their different tumoricidal abilities were clarified by analyzing gene expression profiles in the two types of UCMSC. Microarray analysis revealed differential gene expression between untreated naïve UCMSC and those co-cultured with species-matched breast carcinoma cells. The analyses screened 17 differentially expressed genes that are commonly detected in both human and rat UCMSC. The comparison between the two sets of gene expression profiles identified two tumor suppressor genes, adipose-differentiation related protein (ADRP) and follistatin (FST), that were specifically up-regulated in rat UCMSC, but down-regulated in human UCMSC when they were co-cultured with the corresponding species’ breast carcinoma cells. Over-expression of FST, but not ADRP, in human UCMSC enhanced their ability to suppress the growth of MDA-231 cells. The growth of MDA-231 cells was also significantly lower when they were cultured in medium conditioned with FST, but not ADRP over-expressing human UCMSC. In the breast carcinoma lung metastasis model generated with MDA-231 cells, systemic treatment with FST-over-expressing human UCMSC significantly attenuated the tumor burden. These results suggest that FST may play an important role in exhibiting stronger tumoricidal ability in rat UCMSC than human UCMSC and also implies that human UCMSC can be transformed into stronger tumoricidal cells by enhancing tumor suppressor gene expression.

Identification and Characterization of Unique Tumoricidal Genes in Rat Umbilical Cord Matrix Stem Cells

Rat umbilical cord matrix stem cells (UCMSC) have been shown to exhibit a remarkable ability to control rat mammary adenocarcinoma (Mat B III) cell proliferation both in vivo and in vitro. To study the underlying mechanisms and genes involved in Mat B III growth attenuation, total RNA was extracted from the naive rat UCMSC alone and those cocultured with Mat B III in Transwell culture dishes. Gene expression profiles of naive rat UCMSC alone and those cocultured with Mat B III cells were investigated by microarray analysis using an Illumina RatRef-12 Expression BeadChip. The comparison of gene expression profiles between untreated and cocultured rat UCMSC identified five upregulated candidate genes (follistatin (FST), sulfatase1 (SULF-1), glucose phosphate isomerase (GPI), HtrA serine peptidase (HTRA1), and adipocyte differentiation-related protein (ADRP)) and two downregulated candidate genes (transforming growth factor, beta-induced, 68 kDa (TGFβI) and podoplanin (PDPN)) based upon the following screening criteria: (1) expression of the candidate genes should show at least a 1.5-fold change in rat UCMSC cocultured with Mat B III cells; (2) candidate genes encode secretory proteins; and (3) they encode cell growth-related proteins. Following confirmation of gene expression by real-time PCR, ADRP, SULF-1 and GPI were selected for further analysis. Addition of specific neutralizing antibodies against these three gene products or addition of gene-specific siRNAs individually in cocultures of 1:20 rat UCMSC:Mat B III cells significantly increased cell proliferation, implying that these gene products are produced under the cocultured condition and functionally attenuate cell growth. Immunoprecipitation followed by Western blot analysis demonstrated that these proteins are indeed secreted into the culture medium. Individual overexpression of these three genes in rat UCMSC significantly enhanced UCMSC-dependent inhibition of cell proliferation in coculture. These results suggest that ADRP, SULF-1 and GPI act as tumor suppressor genes, and these genes might be involved in rat UCMSC-dependent growth attenuation of rat mammary tumors.

AT2R Gene Delivered by Condensed Polylysine Complexes Attenuates Lewis Lung Carcinoma after Intravenous Injection or Intratracheal Spray

Transfection efficiency and toxicity concerns remain a challenge for gene therapy. Cell-penetrating peptides (CPP) have been broadly investigated to improve the transfection of genetic material (e.g., pDNA and siRNA). Here, a synthetic CPP (polylysine, K9 peptide) was complexed with angiotensin II type 2 receptor (AT2R) plasmid DNA (pAT2R) and complexes were condensed using calcium chloride. The resulting complexes were small (∼150 nm) and showed high levels of gene expression in vitro and in vivo. This simple nonviral formulation approach showed negligible cytotoxicity in four different human cell lines (cervix, breast, kidney, and lung cell lines) and one mouse cell line (a lung cancer cell line). In addition, this K9-pDNA-Ca2+ complex demonstrated cancer-targeted gene delivery when administered via intravenous injection or intratracheal spray. The transfection efficiency was evaluated in Lewis lung carcinoma (LLC) cell lines cultured in vitro and in orthotopic cancer grafts in syngeneic mice. Immunohistochemical analysis confirmed that the complex effectively delivered pAT2R to the cancer cells, where it was expressed mainly in cancer cells along with bronchial epithelial cells. A single administration of these complexes markedly attenuated lung cancer growth, offering preclinical proof-of-concept for a novel nonviral gene delivery method exhibiting effective lung tumor gene therapy via either intravenous or intratracheal administration. Mol Cancer Ther; 15(1); 209–18. ©2015 AACR.

Exopolysaccharides extracted from Parachlorella kessleri inhibit colon carcinoma growth in mice via stimulation of host antitumor immune responses

The newly purified extracellular polysaccharides (exopolysaccharides) from Parachlorella kessleri (PCEPS) were evaluated on their antitumor and immunomodulatory effects in cell culture and mouse colon carcinoma peritoneal dissemination model. In two-dimensional cell culture, the PCEPS treatment inhibited cell growth of both murine and human colon carcinoma cells in a dose- and time-dependent manner. In contrast, the growth of mouse splenocytes (SPLs) and bone marrow cells (BMCs) were stimulated by the treatment with PCEPS. The treatment with PCEPS also increased specific subpopulations of the cells in BMCs: antigen presenting cells (CD19+ B cells, 33D1+ dendritic cells and CD68+ macrophage) and CD8+ cytotoxic T cells. In three-dimensional spheroid culture, spheroid growth of CT26 cells co-cultured with HL-60 human neutrophilic promyeloblasts and Jurkat cells (human lymphoblasts), but not THP-1 human monocyte/macrophage was significantly attenuated by PCEPS treatment. In a mouse CT26 colon carcinoma peritoneal dissemination model, intraperitoneal injection of PCEPS (10 mg/kg, twice per week) significantly attenuated the growth of CT26 colon carcinoma in syngeneic mice. The present study suggests that PCEPS inhibits colon carcinoma growth via direct cell growth inhibition and a stimulation of the host antitumor immune responses. Taken together, the current study suggests that exopolysaccharides derived from Parachlorella kessleri contain significant bioactive materials that inhibit colon carcinoma growth.

Co-treatment with a C1B5 peptide of protein kinase Cγ and a low dose of gemcitabine strongly attenuated pancreatic cancer growth in mice through T cell activation

Although gemcitabine is an effective chemotherapeutic for pancreatic cancer, severe side effects often accompany its use. Since we have discovered that locally administered C1B domain peptides effectively control tumor growth without any side effects, the efficacy of co-treatment with this peptide and a low dose of gemcitabine on the growth of pancreatic cancer was examined. Two- and three-dimensional cell culture studies clarified that a co-treatment with C1B5 peptide and gemcitabine significantly attenuated growth of PAN02 mouse and PANC-1 human pancreatic cancer cells in 2D and 3D cultures. Although treatment with the low dose of gemcitabine alone (76%) or the C1B5 peptide alone (39%) inhibited tumor growth moderately, a co-treatment with C1B5 peptide and a low dose of gemcitabine markedly inhibited the growth of PAN02 autografts in the mouse peritoneal cavity (94% inhibition) without any noticeable adverse effect. The number of peritoneal cavity-infiltrating neutrophils and granzyme B+ lymphocytes was significantly higher in the co-treatment group than in the control group. A significant increase of granzyme B mRNA expression was also detected in human T cells by the co-treatment. Taken together, the current study suggests that C1B5 peptide offers a remarkably effective combination treatment strategy to reduce side effects associated with gemcitabine, without losing its tumoricidal effect.

Abstract 1107: Co-treatment with a C1B5 domain peptide of protein kinase Cγ and a low dose of gemcitabine effectively inhibited pancreatic cancer growth in mouse peritoneal cavity

Although the gemcitabine is an effective chemotherapeutic agent for pancreatic cancer, unacceptable side effects often accompany. Since we have previously discovered that PKCγ C1B domain peptides effectively control tumor growth without any side effect (Kawabata et. al, Cancer Biol Ther, 2012), we sought to examine the efficacy of co-treatment with this peptide and a low dose of gemcitabine on the growth of pancreatic cancer. Although individual and co-treatment with C1B5 peptide (1µM) and gemcitabine (20 nM) weakly inhibited growth of PAN02 murine pancreatic acinar cell carcinoma in 2D culture, either treatment effectively attenuated spheroid growth on PAN02 cells in 3D culture with 48.2% and 35.8% inhibition, respectively. Combination treatment with the C1B5 peptide and gemcitabine further attenuated the growth of PAN02 cells (69.5% inhibition). In mice bearing peritoneal allograft tumors of PAN02 cells (2.5 x 105 cells/mouse), combination treatment with C1B5 peptide at 20 mg/kg (every other day) and gemcitabine 15 mg/kg (every three days) markedly inhibited tumor growth of PAN02 allografts (94% inhibition) more than individual treatment with gemcitabine (76% inhibition) or C1B5 peptide (39% inhibition). The tumor growth inhibition by the combination treatment was similar to the higher dose (50 mg/kg) of gemcitabine alone treatment. Peritoneal cavity infiltrated neutrophils and granzime B+ lymphocyte numbers were significantly higher in combination treatment group than in control group. In cell culture study, the treatment with C1B5 peptide alone (1µM) significantly increased INF-γ, IL-2, and TNF-α mRNA levels, suggesting that C1B5 peptide directly stimulated Jurkat cell activation. These studies suggest that stimulation of leucocyte migration toward cancer tissues and activation of cytotoxic T cells may play important roles in tumor growth attenuation by the combination treatment of C1B5 peptide and gemcitabine. Taken together, the current study suggests that C1B5 peptide offers an effective combination treatment strategy to reduce side effects associated with gemcitabine without losing tumoricidal effect of this agent. This work is supported in part by Kansas State University Johnson Cancer Research Center, NIH grants P20 GM103418, and Kansas State Bioscience Authority Collaborative Cancer Research grant. Citation Format: Alejandro Zulbaran, Kelsey Monson, Susumu Ishiguro, Atsushi Kawabata, Deepthi Uppalapati, Naomi Ohta, Masaaki Tamura. Co-treatment with a C1B5 domain peptide of protein kinase Cγ and a low dose of gemcitabine effectively inhibited pancreatic cancer growth in mouse peritoneal cavity [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 1107. doi:10.1158/1538-7445.AM2017-1107

Abstract 3751: Apoptosis inducer gene delivery by polylysine-calcium complexes attenuates mouse lung carcinoma allograft growth after intravenous injection or intratracheal spray

Transfection efficiency and toxicity concerns remain a challenge for gene therapy. Nanoparticle-based gene delivery technique potentially overcomes these concerns and may be applicable to cancer gene therapy. Cell penetrating peptides (CPPs) have been broadly investigated to improve the transfection of genetic material (e.g., pDNA and siRNA). Our previous study demonstrated that an apoptosis inducer, angiotensin II type 2 receptor plasmid DNA (pAT2R) encapsulated in a modified HIV-1 TAT peptide (dTAT-pAT2R), significantly attenuated the growth of Lewis lung carcinoma (LLC) allograft in mouse lungs (Kawabata et al., Cancer Res, 2012). Here, we report a newly synthesized polylysine CPP (K9 peptide)-based gene therapy for lung cancer treatment. The pAT2R and K9 peptide (K9-pAT2R) complexes were condensed using calcium chloride (K9-pAT2R-Ca2+). The resulting complexes were small (∼150 nm) and showed high levels of gene expression in vitro. This simple non-viral formulation approach showed negligible cytotoxicity in several different human and mouse cell lines (human cervix, breast, kidney, and human and mouse lung cell lines). Additionally, this K9-pDNA-Ca2+ complex demonstrated cancer targeted gene delivery when administered via intravenous (IV) injection or intratracheal (IT) spray into LLC orthotopic allograft-bearing mice. Average lung weights (mg) of the K9-pAT2R-Ca2+ IT (190.6±48.3) and the K9-pAT2R-Ca2+ IV (201.6±67.0) treated groups were significantly smaller than that of the control PBS group (325.7±69.4, P

Abstract 5533: A local chemotherapy with hyaluronan-cisplatin conjugate significantly attenuates growth of lung adenocarcinoma xenografts in mouse model

Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA Nanoparticle-based chemotherapy, while promising, remains clinically unsuccessful, mainly due to a lack of targeted delivery methods of the therapeutics into cancer tissues and the side effect of chemotherapeutics. We have demonstrated that the nanoparticle formulation with hyaluronan-cisplatin conjugates (HylaPlat) is suggested to be an effective chemotherapeutic delivery method in breast cancer mouse models (Cai, et al., J Surg Res., 2008; Cai, et al., Ther Deliv, 2011). The objectives of the present study were to examine the growth inhibition efficacy of HylaPlat formulation on lung adenocarcinoma cells in cell culture and to examine the therapeutic efficiency of the local administration of HylaPlat on lung adenocarcinoma in mice. Effect of the HylaPlat on the growth of lung carcinoma was evaluated using Lewis Lung carcinoma (LLC) cells in 2D culture and 3D spheroid cell culture, as well as, orthotopic autografts in C57BL/6 mice lungs. Cell culture studies clarified that the HylaPlat effectively attenuated cell growth in 2D and 3D spheroid culture with IC50 of 0.35μM and 1.35 μM, respectively; whereas control cisplatin-dependent growth inhibition was achieved with several fold higher concentrations (IC50 1.64 and 3.6 μM, respectively). The 3D spheroid cell culture study also revealed that the treatment with HylaPlat induced apoptosis in the cells located on the peripheral area of the spheroid first, this effect lasted for several days. A single intratracheal administration of 7.5mg/kg HylaPlat (1mg cisplatin equivalent/kg) seven days after LLC cell inoculation almost completely inhibited growth of LLC autografts in the mouse lungs. Histological analysis of dissected lungs revealed that a small number of microscopic tumor nodules were detected in the treated mouse lungs, whereas several large tumors were detected in the untreated control mouse lungs. Normal lung architectures of the trachea, bronchioles and alveoli were maintained in the treated mice although small inflammation spots can be detected at peripheral areas. Apoptotic index was significantly higher in the treated tumors than PBS treated control tumors, suggesting that cisplatin was successfully delivered to the tumor tissues by nanoparticle formulated HylaPlat and caused apoptosis of tumor cells. The pharmacokinetics of cisplatin 14 days after intratracheal administration of HylaPlat is under investigation. Taken together, the current study suggests that an intratracheal administration of HylaPlat nanoparticles offer an effective strategy for lung cancer treatment. This work was supported by the Kansas State University Johnson Cancer Research Center, Kansas Bioscience Authority Collaborative Cancer Research grant, 1R01CA173292 (LF) and American Cancer Society RSG-08-133-01-CDD (LF). Citation Format: Susumu Ishiguro, Deepthi Uppalapati, Shuang Cai, Katie Turner, Jacob Hodge, Laird Forest, Masaaki Tamura. A local chemotherapy with hyaluronan-cisplatin conjugate significantly attenuates growth of lung adenocarcinoma xenografts in mouse model. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5533. doi:10.1158/1538-7445.AM2015-5533

Abstract 220: Human umbilical cord matrix-derived stem cells control tumor growth by tumor suppressor gene expression.

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC Umbilical cord matrix derived stem cells (UCMSC) have the potential to treat various diseases including cancer. We have shown that naive human and rat UCMSC significantly attenuate proliferation of multiple cancer cells (Ganta et al., Cancer Res., 2009. Ayuzawa et al., Cancer Lett., 2009). However, the growth attenuation ability of rat UCMSC is stronger than that of human UCMSC. To clarify their different tumoricidal abilities, differential gene expression profiles of these two cells were studied by micro-array analysis using Illumina HumanRef-8 V2 for human and RatRef-12 BeadChip for rat UCMSC. The gene expression profiles were compared between UCMSC untreated and co-cultured with either human (MDA-231) or rat breast carcinoma cells (Mat B III). Selection criteria used for the screening of candidate genes associated with UCMSC-dependent tumoricidal ability are as follows; 1) gene expression difference should be at least a 1.5 fold between naive UCMSC and those co-cultured with mammary tumor cells; 2) they must encode secretory proteins; and 3) they must encode cell growth regulation-related proteins. These analyses screened 16 common genes from both human and rat UCMSC. The comparison between two sets of gene expression profiles identified that two genes, adipose-differentiation related protein (ADRP) and follistatin (FST), were specifically up-regulated in rat UCMSC, whereas they were down-regulated in human UCMSC when they were co-cultured with the corresponding species’ breast cancer cells. The suppression of either protein by adding specific neutralizing antibody in culture of rat UCMSC significantly abrogated their ability to attenuate cell growth. Over-expression of both genes by adenovirus vector in human UCMSC enhanced their ability to suppress the growth of MDA-231 cells. FST over-expression in MDA 231 cells also decreased their growth significantly. In the experimental lung metastasis model with MDA 231 cells in immunodeficient mice, the treatment with FST-over-expressing human UCMSC was administered three times, at one week intervals, via tail vein injection, starting 6 days after tumor cell inoculation. Examination 4 weeks after tumor inoculation showed a significant decrease in the number of tumor nodules in the lungs. Both ADRP and FST are considered to be tumor suppressor genes. These results suggest that both ADRP and FST may play important roles in exhibiting a stronger tumoricidal ability in rat UCMSC than human UCMSC. These results imply that human UCMSC can be transformed into stronger tumoricidal cells by enhancing tumor suppressor gene expression. This work was supported by the Kansas State University (KSU) Terry C. Johnson Center for Basic Cancer Research, KSU College of Veterinary Medicine Deans Fund, NIH RR017686, RR15563, CA135599, Kansas Bioscience Authority research grant. Citation Format: Naomi Ohta, Susumu Ishiguro, Atsushi Kawabata, Deepthi Uppalapati, Marla Pyle, Deryl Troyer, Supriyo De, Yongqing Zhang, Kevin G. Becker, Masaaki Tamura. Human umbilical cord matrix-derived stem cells control tumor growth by tumor suppressor gene expression. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 220. doi:10.1158/1538-7445.AM2013-220