Gastrin-releasing peptide (GRP), the mammalian equivalent of bombesin (BBS), is a trophic factor for highly vascular neuroblastomas; its mechanisms of action in vivo are unknown. We sought to determine the effects of BBS on the growth of neuroblastoma xenografts and on angiogenesis. BBS significantly increased the growth of SK-N-SH and BE(2)-C human neuroblastomas; tumors demonstrated increased expression of angiogenic markers, PECAM-1 and VEGF, as well as phosphorylated (p)-Akt levels. RC-3095, a BBS/GRP antagonist, attenuated BBS-stimulated tumor growth and angiogenesis in vivo. GRP or GRPR silencing significantly inhibited VEGF as well as p-Akt and p-mTOR expression in vitro. Our findings demonstrate that BBS stimulates neuroblastoma growth and the expression of angiogenic markers. Importantly, these findings suggest that novel therapeutic agents, targeting BBS-mediated angiogenesis, may be useful adjuncts in patients with advanced-stage neuroblastomas.
Background:Oxidative stress and inflammation may contribute to the disruption of the protective gut barrier through various mechanisms; mitochondrial dysfunction resulting from inflammatory and oxidative injury may potentially be a significant source of apoptosis during necrotizing enterocolitis (NEC). Tumor necrosis factor (TNF)α is thought to generate reactive oxygen species (ROS) and activate the apoptosis signal-regulating kinase 1 (ASK1)-c-Jun N-terminal kinase (JNK)/p38 pathway. Hence, the focus of our study was to examine the effects of TNFα/ROs on mitochondrial function, ASK1-JNK/p38 cascade activation in intestinal epithelial cells during NEC.Results:We found (a) abundant tissue TNFα and ASK1 expression throughout all layers of the intestine in neonates with NEC, suggesting that TNFα/ASK1 may be a potential source (indicators) of intestinal injury in neonates with NEC; (b) TNFα-induced rapid and transient activation of JNK/p38 apoptotic signaling in all cell lines suggests that this may be an important molecular characteristic of NEC; (c) TNFα-induced rapid and transient ROs production in RIe-1 cells indicates that mitochondria are the predominant source of ROS, demonstrated by significantly attenuated response in mitochondrial DNA-depleted (RIE-1-ρ°) intestinal epithelial cells; (d) further studies with mitochondria-targeted antioxidant PBN supported our hypothesis that effective mitochondrial ROS trapping is protective against TNFα/ROs-induced intestinal epithelial cell injury; (e) TNFα induces significant mitochondrial dysfunction in intestinal epithelial cells, resulting in increased production of mtROS, drop in mitochondrial membrane potential (MMP) and decreased oxygen consumption; (f) although the significance of mitochondrial autophagy in NEC has not been unequivocally shown, our studies provide a strong preliminary indication that TNFα/ROs-induced mitochondrial autophagy may play a role in NeC, and this process is a late phenomenon.Methods:Paraffin-embedded intestinal sections from neonates with NEC and non-inflammatory condition of the gastrointestinal tract undergoing bowel resections were analyzed for TNFα and ASK1 expression. Rat (RIE-1) and mitochondrial DNA-depleted (RIE-1-ρ°) intestinal epithelial cells were used to determine the effects of TNFα on mitochondrial function.Conclusions:Our findings suggest that TNFα induces significant mitochondrial dysfunction and activation of mitochondrial apoptotic responses, leading to intestinal epithelial cell apoptosis during NeC. Therapies directed against mitochondria/ROS may provide important therapeutic options, as well as ameliorate intestinal epithelial cell apoptosis during NeC.
In this study, the clinical prototype PTeye demonstrated high accuracy for label-free intraoperative parathyroid identification. The intuitive interface of the PTeye that can guide in identifying parathyroid tissue in the presence of ambient room lights suggests that it is a reliable and easy-to-use tool for surgical personnel.
Summary Patient-derived cancer organoids hold great potential to accurately model and predict therapeutic responses. Efficient organoid isolation methods that minimize post-collection manipulation of tissues would improve adaptability, accuracy, and applicability to both experimental and real-time clinical settings. Here we present a simple and minimally invasive fine-needle aspiration (FNA)-based organoid culture technique using a variety of tumor types including gastrointestinal, thyroid, melanoma, and kidney. This method isolates organoids directly from patients at the bedside or from resected tissues, requiring minimal tissue processing while preserving the histologic growth patterns and infiltrating immune cells. Finally, we illustrate diverse downstream applications of this technique including in vitro high-throughput chemotherapeutic screens, in situ immune cell characterization, and in vivo patient-derived xenografts. Thus, routine clinical FNA-based collection techniques represent an unappreciated substantial source of material that can be exploited to generate tumor organoids from a variety of tumor types for both discovery and clinical applications.
PI3-K pathway is activated during ROS-induced intestinal epithelial cell injury; IGF-1 exerted an anti-apoptotic effect during this response by PI3-K activation. A better understanding of the exact role of IGF-1-mediated activation of PI3-K may allow us to facilitate the development of novel therapy against NEC.
Background and Objective: The Food and Drug Administration has cleared a probebased near-infrared autofluorescence (NIRAF) detection system called PTeye™ as an adjunct tool for label-free intraoperative parathyroid gland (PG) identification.Since PTeye™ has been investigated only in a "blinded" manner to date, this study describes the preliminary impressions of PTeye™ when used by surgeons without being blinded to the device output.Methods: Patients undergoing thyroid and parathyroid procedures were prospectively recruited. Target tissues were intraoperatively assessed with PTeye™. The surgeon's confidence in PG identification was recorded concomitantly with NIRAF parameters that were output in real-time from PTeye™.Results: A retrospective review of prospectively collected data on 83 patients was performed. PTeye™ was used for interrogating 336 target tissues in 46 parathyroid and 37 thyroid procedures. PTeye™ yielded an overall accuracy of 94.3% with a positive predictive value of 93.0% and a negative predictive value of 100%. An increase in confidence for intraoperative PG identification with PTeye™ was observed by all three participating high-volume surgeons, irrespective of their level of accrued surgical experience.
Background: Difficulty in identifying the parathyroid gland (PG) during neck operations can lead to accidental PG excisions and post-surgical hypocalcemia. The PTeye (“parathyroid eye”) was developed to guide PG identification using a fiber-optic probe that detects near infra-red auto-fluorescence (NIRAF) from PGs as operating room (OR) lights remain on. An Overlay Tissue Imaging System (OTIS) was designed concurrently to detect NIRAF and project visible light precisely onto PG location. Methods: The PTeye and the OTIS were tested in 20 and 15 patients respectively, while a modified near infrared imaging system (NIRIS) was investigated in 6 patients. All 41 patients underwent thyroidectomy or parathyroidectomy. System accuracy was ascertained with surgeon’s visual confirmation for in-situ PGs and histology for excised PGs. Results: There was no observable difference between NIRAF of healthy and diseased PGs. The PTeye identified 98% of the PG, while the NIRIS and the OTIS identified 100% and 97% of the PGs respectively. Conclusions: The PTeye can guide in real-time PG identification even with ambient OR lights. The NIRIS performs PG imaging with high sensitivity, while the OTIS enhances PG visualization directly within the surgical field without requiring display monitors. These label-free technologies can be valuable adjuncts for identifying PGs intraoperatively.
Objective: With the recent approval of 2 NIRAF-based devices for label-free identification of PG by the Food and Drug Administration, it becomes crucial to educate the surgical community on the realistic scope of this emerging technology. Here, we have compiled a review of studies that utilize NIRAF and present a critical appraisal of this technique for intraoperative PG detection. Background: Failure to visualize PGs could lead to accidental damage/excision of healthy PGs or inability to localize diseased PGs, resulting in postsurgical complications. The discovery that PGs have NIRAF led to new avenues for intraoperatively identifying PGs with high accuracy in real-time. Methods: Using the following key terms: “parathyroid, near infrared, autofluorescence” in various search engines such as PubMed and Google Scholar, we identified various publications relevant to this review of NIRAF as a technique for PG identification. Articles were excluded if they focused solely on contrast agents, served as commentaries/overviews on NIRAF or were not written in English. Results: To date, studies have investigated the potential of NIRAF detection for (i) identifying PG tissues intraoperatively, (ii) locating PGs before or after dissection, (iii) distinguishing healthy from diseased PGs, and (iv) minimizing postoperative hypocalcemia after total thyroidectomy. Conclusions: Because NIRAF-based identification of PG is noninvasive and label-free, the popularity of this approach has considerably surged. As the present limitations of various technologies capable of NIRAF detection are identified, we anticipate that newer device iterations will continue to be developed enhancing the current merits of these modalities to aid surgeons in identifying and preserving PGs. However, more concrete and long-term outcome studies with these modalities are essential to determine the impact of this technique on patient outcome and actual cost-benefits.
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