Substance P Receptor Antagonism Enhances Chemotherapeutic Responses in Triple Negative Breast Cancer

https://openworks.mdanderson.org/sumexp22/1124/thumbnail.jp

Substance P Signaling Contributes to Granuloma Formation in Taenia crassiceps Infection, a Murine Model of Cysticercosis

Cysticercosis is an infection with larval cysts of the cestode Taenia solium. Through pathways that are incompletely understood, dying parasites initiate a granulomatous reaction that, in the brain, causes seizures. Substance P (SP), a neuropeptide involved in pain-transmission, contributes to inflammation and previously was detected in granulomas associated with dead T. crassiceps cysts. To determine if SP contributes to granuloma formation, we measured granuloma-size and levels of IL-1β, TNF-α, and IL-6 within granulomas in T. crassiceps-infected wild type (WT) mice and mice deficient in SP-precursor (SPP) or the SP-receptor (neurokinin 1, NK1). Granuloma volumes of infected SPP- and NK1-knockout mice were reduced by 31 and 36%, respectively, compared to WT mice (P < .05 for both) and produced up to 5-fold less IL-1β, TNF-α, and IL-6 protein. Thus, SP signaling contributes to granuloma development and proinflammatory cytokine production in T. crassiceps infection and suggests a potential role for this mediator in human cystercercosis

Substance P Causes Seizures in Neurocysticercosis

Neurocysticercosis (NCC), a helminth infection of the brain, is a major cause of seizures. The mediators responsible for seizures in NCC are unknown, and their management remains controversial. Substance P (SP) is a neuropeptide produced by neurons, endothelial cells and immunocytes. The current studies examined the hypothesis that SP mediates seizures in NCC. We demonstrated by immunostaining that 5 of 5 brain biopsies from NCC patients contained substance P (SP)-positive (+) cells adjacent to but not distant from degenerating worms; no SP+ cells were detected in uninfected brains. In a rodent model of NCC, seizures were induced after intrahippocampal injection of SP alone or after injection of extracts of cysticercosis granuloma obtained from infected wild type (WT), but not from infected SP precursor-deficient mice. Seizure activity correlated with SP levels within WT granuloma extracts and was prevented by intrahippocampal pre-injection of SP receptor antagonist. Furthermore, extracts of granulomas from WT mice caused seizures when injected into the hippocampus of WT mice, but not when injected into SP receptor (NK1R) deficient mice. These findings indicate that SP causes seizures in NCC, and, suggests that seizures in NCC in humans may be prevented and/or treated with SP-receptor antagonists

Genetic and Small-Molecule Modulation of Stat3 in a Mouse Model of Crohn&rsquo;s Disease

Crohn&rsquo;s disease (CD), is an inflammatory bowel disease that can affect any part of the gastro-intestinal tract (GI) and is associated with an increased risk of gastro-intestinal cancer. In the current study, we determined the role of genetic and small-molecule modulation of STAT3 in a mouse model of CD. STAT3 has 2 isoforms (&alpha;, &beta;) which are expressed in most cells in a 4:1 ratio (&alpha;: &beta;). STAT3&alpha; has pro-inflammatory and anti-apoptotic functions, while STAT3&beta; has contrasting roles. We used an animal model of CD consisting of intrarectal administration of 2,4,6-trinitrobenzene sulfonic acid and examined the severity of CD in transgenic-mice that express only STAT3&alpha; (&#8710;&beta;/&#8710;&beta;), as well as in wild-type (WT) mice administered TTI-101 (formerly C188-9), a small molecule STAT3 inhibitor. We determined that clinical manifestations of CD, such as mortality, rectal-bleeding, colonic bleeding, diarrhea, and colon shortening, were exacerbated in &#8710;&beta;/&#8710;&beta; transgenic versus cage-control WT mice, while they were markedly decreased by TTI-101 treatment of WT mice. TTI-101 treatment also increased apoptosis of pathogenic CD4+ T cells and reduced colon levels of IL-17-positive cells. Our results indicate that STAT3 contributes to CD and that targeting of STAT3 with TTI-101 may be a useful approach to treating CD

Substance P-Friend or Foe.

Substance P (SP), a neuropeptide and pain transmitter has multiple roles and is involved in various processes in the body [...]

Contribution of STAT3 to Inflammatory and Fibrotic Diseases and Prospects for its Targeting for Treatment

Signal transducer and activator of transcription (STAT) 3 plays a central role in the host response to injury. It is activated rapidly within cells by many cytokines, most notably those in the IL-6 family, leading to pro-proliferative and pro-survival programs that assist the host in regaining homeostasis. With persistent activation, however, chronic inflammation and fibrosis ensue, leading to a number of debilitating diseases. This review summarizes advances in our understanding of the role of STAT3 and its targeting in diseases marked by chronic inflammation and/or fibrosis with a focus on those with the largest unmet medical need

Sequential Expression of the Neuropeptides Substance P and Somatostatin in Granulomas Associated with Murine Cysticercosis

Neurocysticercosis, a parasitic infection of the human central nervous system caused by Taenia solium, is a leading cause of seizures. Seizures associated with neurocysticercosis are caused mainly by the host inflammatory responses to dying parasites in the brain parenchyma. We previously demonstrated sequential expression of Th1 cytokines in early-stage granulomas, followed by expression of Th2 cytokines in later-stage granulomas in murine cysticercosis. However, the mechanism leading to this shift in cytokine response in the granulomas is unknown. Neuropeptides modulate cytokine responses and granuloma formation in murine schistosomiasis. Substance P (SP) induces Th1 cytokine expression and granuloma formation, whereas somatostatin inhibits the granulomatous response. We hypothesized that neuropeptides might play a role in regulation of the granulomatous response in cysticercosis. To test this hypothesis, we compared expression of SP and expression of somatostatin in murine cysticercal granulomas by using in situ hybridization and immunohistochemistry. We also compared expression with granuloma stage. Expression of SP mRNA was more frequent in the early-stage granulomas than in the late-stage granulomas (34 of 35 early-stage granulomas versus 1 of 13 late-stage granulomas). By contrast, somatostatin was expressed primarily in later-stage granulomas (13 of 14 late-stage granulomas versus 2 of 35 early-stage granulomas). The median light microscope grade of SP mRNA expression in the early-stage granulomas was significantly higher than that in the late-stage granulomas (P = 0.008, as determined by the Wilcoxon signed rank test). By contrast, somatostatin mRNA expression was higher at later stages (P = 0.008, as determined by the Wilcoxon signed rank test). SP and somatostatin are therefore temporally expressed in granulomas associated with murine cysticercosis, which may be related to differential expression of Th1 and Th2 cytokines

Genetic and Small-Molecule Modulation of Stat3 in a Mouse Model of Crohn’s Disease

Crohn’s disease (CD), is an inflammatory bowel disease that can affect any part of the gastro-intestinal tract (GI) and is associated with an increased risk of gastro-intestinal cancer. In the current study, we determined the role of genetic and small-molecule modulation of STAT3 in a mouse model of CD. STAT3 has 2 isoforms (α, β) which are expressed in most cells in a 4:1 ratio (α: β). STAT3α has pro-inflammatory and anti-apoptotic functions, while STAT3β has contrasting roles. We used an animal model of CD consisting of intrarectal administration of 2,4,6-trinitrobenzene sulfonic acid and examined the severity of CD in transgenic-mice that express only STAT3α (∆β/∆β), as well as in wild-type (WT) mice administered TTI-101 (formerly C188-9), a small molecule STAT3 inhibitor. We determined that clinical manifestations of CD, such as mortality, rectal-bleeding, colonic bleeding, diarrhea, and colon shortening, were exacerbated in ∆β/∆β transgenic versus cage-control WT mice, while they were markedly decreased by TTI-101 treatment of WT mice. TTI-101 treatment also increased apoptosis of pathogenic CD4+ T cells and reduced colon levels of IL-17-positive cells. Our results indicate that STAT3 contributes to CD and that targeting of STAT3 with TTI-101 may be a useful approach to treating CD