Abstract TGFb signaling is known to play a central role in tumor biology, via inducing and/or enhancing tumor cell growth and differentiation, modulating the extracellular matrix in the stroma, inducing epithelial to mesenchymal transition, modulating angiogenesis, and inhibiting immune surveillance and anti-tumor immunity. Galunisertib is a pharmacological inhibitor of the TGFb pathway which acts by inhibiting signaling though TGFbRI. Galunisertib is currently being evaluated clinically in several Phase I and II studies; as a monotherapy, galunisertib has shown antitumor activity against a variety of tumors, including durable and long-term responses in patients with glioma. To explore the impact of Galunisertib monotherapy on anti-tumor T cell immunity, we utilized murine tumor models. Treatment of mice with well-established 4T1-LP (poorly immunogenic 4T1 breast tumor engineered to express luciferase) implanted in the mammary fat pad resulted in strong dose-dependent anti-tumor activity with nearly 100% inhibition of tumor growth across doses during the dosing period, with complete tumor responses upon cessation of treatment in ~50% of animals at the highest dose tested; depletion studies demonstrated that regression of 4T1-LP was dependent on the presence of CD8+ T cells. Rechallenge of treated, tumor free mice resulted in complete rejection of 4T1-LP tumor cells but no rejection of EMT6-LM2 tumor cells, demonstrating the establishment of a durable response and immunological memory. Treatment of mice bearing established parental 4T1 tumors in the mammary fat pad resulted in no significant inhibition of tumor growth, indicating that the presence of a foreign antigen (i.e. LP), potentially enhanced the ability to regress the 4T1-LP derivative. Animals that rejected the immunogenic 4T1-LP tumors were able to also reject 4T1 parental cells upon rechallenge, suggesting the development of a secondary immune response via antigen spreading as a consequence of effective tumor targeting. In the CT26 murine colon carcinoma model, treatment of established tumors with galunisertib or anti-PD-L1 as monotherapies resulted in tumor growth inhibition compared to control of 75% and 86%, respectively (T/C values of 25% and 14%); complete responders were observed in about 20% of treated animals in both monotherapy groups. Combination of galunisertib with anti-PD-L1 resulted in an enhanced tumor growth inhibition of 98% (T/C value of ~2%), and a complete response rate of ~50%, suggesting at least additive activity with potential for synergy when targeting the TGFb and PD-1 pathways. Taken together, these data demonstrate the potential for galunisertib treatment to enhance the development of anti- tumor T cell immunity, which can be enhanced by combinations with immune check point inhibitors. Citation Format: David Schaer, Yanxia Li, Stephen Castaneda, Ivan Inigo, David Surguladze, Xiaohong Xu, Desiree Nugent, Mary Murphy, Gerald Hall, Karim Benhadji, Susan Guba, Yiwen Li, Michael Kalos, Kyla Driscoll. Targeting the TGFb pathway with galunisertib, a TGFbRI SMI, promotes antitumor immunity leading to durable, complete responses, as monotherapy and in combination with checkpoint inhibition. [abstract]. In: Proceedings of the CRI-CIMT-EATI-AACR Inaugural International Cancer Immunotherapy Conference: Translating Science into Survival; September 16-19, 2015; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(1 Suppl):Abstract nr A091.
Liver metastasis, characterized by the spread of tumors to the liver from other areas, represents a deadly disease with poor prognosis. Currently, there is no effective therapeutic strategies and/or agents to combat liver metastasis primarily due to the insufficient understanding of liver metastasis. To develop a promising strategy for targeting liver metastasis, understanding of a cell origin responsible for liver metastasis and how this cell can be pharmacologically eliminated are therefore crucial. Using diverse tumor models including p53-/- genetic mouse model and syngeneic tumor models, we identified primordial germ cell (PGC)-like tumor cells, which are enriched in earliest liver micro-metastasis (up to 99%), as a cell origin of liver metastasis. PGC-like tumor cells formed earliest micro-metastasis in liver and gradually differentiated into non-PGC-like tumor cells to constitute late macro-metastasis in the course of tumor metastasis. The liver metastasis-initiating cells (PGC-like tumor cells) display cell renewal and differentiation capabilities, resemble primordial germ cells (PGCs) in morphology and PGC marker gene expression, and express higher level of the genes linked to metastasis and immune escape compared with non-PGC-like tumor cells. Of note, Stellarhigh PGC-like tumor cells, but not Stellarlow non-PGC-like cells, sorted from primary tumors of p53-/- mice readily form liver metastasis. Depletion of PGC-like tumor cells through genetic depletion of any of key germ cell genes impairs liver metastasis, while increased PGC-like tumor cells by SMAD2 knockout is correlated with markedly enhanced liver metastasis. Finally, we present the proof of principle evidence that pharmacologically targeting BMP pathways serves as a promising strategy to eliminate PGC-like tumor cells leading to abrogating liver metastasis. Collectively, our study identifies PGC-like tumor cells as a cell origin of liver metastasis, whose depletion by genetically targeting core PGC developmental genes or pharmacologically inhibiting BMP pathways serves a promising strategy for targeting liver metastasis.
Human ERF gene is a transcription factor involved in development, trophoblast differentiation, apoptosis, and cancer progress. To further understand the exact roles of ERF in these processes, here we report that establishment of two ERF knockout human embryonic stem cell (hESC) lines by CRISPR/Cas9 mediated gene targeting. These cell lines exhibited classical hESC morphology and normal karyotype, and highly expressed pluripotent markers, and had differentiation potential in vitro. These cell lines provide good materials to understand the roles of ERF in development, trophoblast differentiation and craniosynostosis for further studies.
Objective To investigate the risk factors of recurrent common bile duct (CBD) stones after treatment with endoscopic retrograde cholangiopancreatography (ERCP). Methods A total of 802 patients with CBD stone and with complete follow-up data were recruited to the study, among which 297 patients were accompanied with gallstone, 222 patients having undergone cholecystectomy before ERCP and 283 having no gallstones. The CBD stone recurrent frequency and the possible risk factors were calculated with uni- and multi-variate logistic regression analysis. Results The patients were followed up at a mean duration of 84. 8 months, and CBD stone re-occurred in 92 (11.5%). Both uni- and multivariate analysis showed gallstones, CBD larger than 1.5 cm, endoscopic mechanical lithotrity (EML) and angle of bile duct less than 120° were risk factors of recurrence. Multivariate analysis showed cholesterol stones, cholangeal stricture or sphincter of Oddis dysfunction (SOD) were all risk factors for reccurrence. Univariate analysis revealed that history of cholecystectomy or Billroth Ⅱ gastrectomy, stones larger than 1.5 cm and multiple stones were risk factors of recurrence. Conclusion For those with CBD stones undergoing ERCP, gallstone,common bile larger than 1. 5cm, EML and the angle of CBD less than 120° are major risk factors of recurrence. History of cholecystectomy and Billroth Ⅱ gastrectomy, SOD, large CBD stone ( ≥1.5 cm), cholesterol stone and multiple stones are also associating risk factors.
Key words:
Cholangiopancreatography, endoscopic retrograde; Choledocholithiasis; Recurrence; Risk factors
Toll-like receptor (TLR) signaling is an emerging pathway in tumor cell invasion and metastasis. Myeloid differentiation protein-2 (MD2) contributes to ligand recognition and activation of TLRs in response to exogenous microbial insults or endogenous agents. We hypothesized that blocking MD2 using a specific inhibitor would prevent TLR4-mediated inflammatory responses and metastatic cancer growth. Here, we report that a MD2 inhibitor, L6H21, inhibited migration and invasion of LPS-activated colon cancer CT26.WT cells. These activities were accompanied by inhibition of nuclear factor-κB (NF-κB) activation, and thereby inhibition of the production of pro-inflammatory cytokines and adhesive molecules in colon cancer cells. Furthermore, L6H21 inhibited CT26.WT metastasis to the lung in BALB/c mice as well as suppressed colitis-induced colon cancer induced by azoxymethane/dextran sulfate sodium (AOM/DSS). Taken together, our results demonstrated that L6H21 suppressed tumor invasion and metastasis through blocking TLR4-MD2/NF-κB signaling axis. These findings reveal that inhibition of MD2 may be an important target for the development of colon cancer therapies.
To investigate the possible involvement of germline mutations in a neurologic condition involving diffuse white matter lesions.The patients were 3 siblings born to healthy parents. We performed homozygosity mapping, whole-exome sequencing, site-directed mutagenesis, and immunoblotting.All 3 patients showed clinical manifestations of ataxia, behavioral and mood changes, premature hair loss, memory loss, and lower back pain. In addition, they presented with inflammatory-like features and recurrent rhinitis. MRI showed abnormal diffuse demyelination lesions in the brain and myelitis in the spinal cord. We identified an insertion in high-temperature requirement A (HTRA1), which showed complete segregation in the pedigree. Functional analysis showed the mutation to affect stability and secretion of truncated protein.The patients' clinical manifestations are consistent with cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL; OMIM #600142), which is known to be caused by HTRA1 mutations. Because some aspects of the clinical presentation deviate from those reported for CARASIL, our study expands the spectrum of clinical consequences of loss-of-function mutations in HTRA1.
Diabetic nephropathy (DN) is one of the most common complications of diabetes. Gradual loss of podocytes is a sign of DN and pyroptosis mechanistically correlates with podocyte injury in DN; however, the mechanism(s) involved remain unknown. Here we reveal that TRIM29 is overexpressed in high glucose (HG)-treated murine podocytes cells and that TRIM29 silencing significantly inhibits podocyte damage due to HG treatment, as evidenced by lower desmin expression and greater nephrin expression. Additionally, flow cytometry analysis showed that TRIM29 silencing significantly inhibited HG treatment-induced pyroptosis, which was confirmed by immunoblotting for NLRP3, active Caspase-1, GSDMD-N, and phosphorylated NF-κB-p65. Conversely, overexpression of TRIM29 could trigger pyroptosis that was attenuated by NF-κB inhibition, indicating that TRIM29 promotes pyroptosis through the NF-κB pathway. Mechanistic studies revealed that TRIM29 interacts with IκBα to mediate its ubiquitination-dependent degradation, which in turn leads to NF-κB activation. Taken together, our data demonstrate that TRIM29 can promote podocyte pyroptosis by activating the NF-κB/NLRP3 pathway. Thus, TRIM29 represents a potentially novel therapeutic target that may also be clinically relevant in the management of DN.