naloxone and Pancreatic-Neoplasms

Pancreatic ductal adenocarcinoma (PDAC) is one of the most common malignant tumors of the pancreas. Preclinical studies show that it evades the immune system with immune checkpoints and promotes tumor development. V-domain Ig suppressor of T cell activation (VISTA) is a new immune-check point from the B7 family and is highly expressed in cancer cells. Overexpression of toll like receptor 4 (TLR4) in pancreatic adenocarcinoma is associated with induced tumorigenesis, tumor growth, resistancy to chemotherapy. Naloxone is an opioid and inhibits TLR4-ligand association. In this study, we investigated the relation of TLR4 and downstream pathways with immune-check point VISTA in pancreatic cancer proliferation. We initially collected pancreatic cancer-related datasets using the GEPIA2 and UALCAN databases. Based on this data obtained the effect of various concentrations and incubation times of naloxone were used on PANC-1 cells proliferation. A combination of naloxone and VISTA-siRNA were applied, and the effect of both naloxone and combined treatment on TLR4, Interleukin 1 receptor associated kinase 4 (IRAK4) and VISTA gene expression were analyzed in pancreatic cancer cells. As a result of analysis with Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR), gene expression levels of TLR4, IRAK4 and VISTA were significantly suppressed and cell proliferation was significantly reduced. We found that administration of naloxone and VISTA-siRNA in combination with PDAC cells suppressed signaling. Therefore, we considered that the relationship between VISTA and TLR4 signaling pathways and the other possible associated signal molecules may be an important marker in determining the response of immune checkpoint inhibitors in cancer treatment.

Topics: B7 Antigens; Carcinoma, Pancreatic Ductal; Humans; Interleukin-1 Receptor-Associated Kinases; Naloxone; Pancreatic Neoplasms; RNA, Small Interfering; Toll-Like Receptor 4

The endogenous opioid system is involved in modulating the experience of pain, the response to stress, and the action of analgesic therapies. Recent human imaging studies have shown a significant tonic modulation of visceral pain, raising the question of whether endogenous opioids tonically modulate the pain of visceral cancer.. Transgenic mice expressing the first 127 amino acids of simian virus 40 large T antigen, under the control of the rat elastase-1 promoter, that spontaneously develop pancreatic cancer were used to investigate the role of endogenous opioids in the modulation of pancreatic cancer pain. Visceral pain behaviors were assessed as degree of hunching and vocalization.. Although mice with late-stage pancreatic cancer displayed spontaneous, morphine-reversible, visceral pain-related behaviors such as hunching and vocalization, these behaviors were absent in mice with early-stage pancreatic cancer. After systemic administration of the central nervous system (CNS)-penetrant opioid receptor antagonists naloxone or naltrexone, mice with early-stage pancreatic cancer displayed significant visceral pain-related behaviors, whereas systemic administration of the CNS-nonpenetrant opioid antagonist naloxone-methiodide did not induce an increase in visceral pain behaviors.. Our findings suggest that a CNS opioid-dependent mechanism tonically modulates early and late-stage pancreatic cancer pain. Understanding the mechanisms that mask this pain in early stage disease and drive this pain in late-stage disease may allow improved diagnosis, treatment, and care of patients with pancreatic cancer.

Topics: Abdominal Pain; Animals; Disease Models, Animal; Female; Immunohistochemistry; Male; Mice; Naloxone; Narcotic Antagonists; Neurotransmitter Agents; Opioid Peptides; Pain Measurement; Pancreatic Neoplasms; Severity of Illness Index; Treatment Outcome

Gemcitabine is the standard of care for advanced pancreatic neoplasia, and exerts its effect through inhibition of DNA synthesis. However, gemcitabine has limited survival benefits. Opioid growth factor (OGF) is an autocrine-produced peptide that interacts with the nuclear receptor, OGFr, to inhibit cell proliferation but is not cytotoxic or apoptotic. The present study was designed to examine whether a combination of chemotherapy with gemcitabine and biotherapy with OGF is more effective than either agent alone in inhibiting pancreatic cancer growth in vitro and in vivo. The combination of OGF (10(-6) M) and gemcitabine (10(-8) M) reduced MIA PaCa-2 cell number from control levels by 46% within 48 h, and resulted in a growth inhibition greater than that of the individual compounds. OGF in combination with 5-fluorouracil also depressed cell growth more than either agent alone. The action of OGF, but not gemcitabine, was mediated by a naloxone-sensitive receptor, and was completely reversible. OGF, but no other endogenous or exogenous opioids, altered pancreatic cancer growth in tissue culture. The combination of OGF and gemcitabine also repressed the growth of another pancreatic cancer cell line, PANC-1. MIA PaCa-2 cells transplanted into athymic mice received 10 mg/kg OGF daily, 120 mg/kg gemcitabine every 3 days; 10 mg/kg OGF daily and 120 mg/kg gemcitabine every 3rd day, or 0.1 ml of sterile saline daily. Tumor incidence, and latency times to tumor appearance, of mice receiving combined therapy with OGF and gemcitabine, were significantly decreased from those of the control, OGF, and gemcitabine groups. Tumor volumes in the OGF, gemcitabine, and OGF/gemcitabine groups were markedly decreased from controls beginning on days 14, 12, and 8, respectively, after tumor cell inoculation. Tumor weight and tumor volume were reduced from control levels by 36-85% in the OGF and/or gemcitabine groups on day 45 (date of termination), and the group of mice exposed to a combination of OGF and gemcitabine had decreases in tumor size of 70% and 63% from the OGF or the gemcitabine alone groups, respectively. This preclinical evidence shows that combined chemotherapy (e.g. gemcitabine) and biotherapy (OGF) provides an enhanced therapeutic benefit for pancreatic cancer.

Topics: Adenocarcinoma; Animals; Antimetabolites, Antineoplastic; Apoptosis; Caspase 3; Caspases; Cell Line, Tumor; Cell Proliferation; Deoxycytidine; Drug Therapy, Combination; Enkephalin, Methionine; Fluorouracil; Gemcitabine; Growth Substances; Humans; Male; Mice; Mice, Nude; Naloxone; Narcotics; Pancreatic Neoplasms; Receptors, Opioid; Tumor Burden; Xenograft Model Antitumor Assays

Opioid growth factor (OGF) is a native endogenous opioid peptide ([Met5]-enkephalin) that interacts with the OGF receptor (OGFr), and serves as a tonically active negative growth factor in neoplasia. To inquire whether OGF modulates anchorage-independent growth, HT-29 human colon cancer cells were grown in soft agar and subjected to this peptide. In contrast to controls, HT-29 cells exposed to OGF had 57% fewer colonies, and these colonies were reduced in area by 75%. The changes induced by OGF were abolished by concomitant treatment with naloxone, indicating a receptor-mediated mechanism for peptide activity. Continuous blockade of opioid-receptor interactions with the potent and long-acting opioid antagonist, naltrexone (NTX), revealed an increase of 81 and 49% in the number and area, respectively, of colonies compared to control levels. These data suggest that OGF is tonically active in neoplastic cells growing in soft agar medium. HT-29 cells studied under anchorage-independent conditions were not influenced in growth by a variety of natural and synthetic opioids, including those selective for micro, delta, and kappa opioid receptors. Similar effects on anchorage-independent growth by OGF and NTX observed for HT-29 cells were recorded in pancreatic adenocarcinoma cells (Mia PaCa-2, Panc-1) and squamous cell carcinoma of the head and neck (CAL-27). These results using anchorage-independent conditions are consistent with previous data showing that OGF can markedly influence tumor growth in xenografts, and suggest that clonogenic assays can be utilized as indicators of tumorigenicity when tumor transplantation experiments are restricted.

Topics: Adenocarcinoma; Carcinoma, Squamous Cell; Cell Adhesion; Cell Division; Colonic Neoplasms; Colony-Forming Units Assay; Enkephalin, Methionine; Head and Neck Neoplasms; Humans; Naloxone; Naltrexone; Narcotic Antagonists; Pancreatic Neoplasms; Receptors, Opioid; Transplantation, Heterologous; Tumor Cells, Cultured