P. Matzner

Perioperative COX-2 and β-Adrenergic Blockade Improves Metastatic Biomarkers in Breast Cancer Patients in a Phase-II Randomized Trial

Purpose: Translational studies suggest that excess perioperative release of catecholamines and prostaglandins may facilitate metastasis and reduce disease-free survival. This trial tested the combined perioperative blockade of these pathways in breast cancer patients. Experimental Design: In a randomized placebo-controlled biomarker trial, 38 early-stage breast cancer patients received 11 days of perioperative treatment with a β-adrenergic antagonist (propranolol) and a COX-2 inhibitor (etodolac), beginning 5 days before surgery. Excised tumors and sequential blood samples were assessed for prometastatic biomarkers. Results: Drugs were well tolerated with adverse event rates comparable with placebo. Transcriptome profiling of the primary tumor tested a priori hypotheses and indicated that drug treatment significantly (i) decreased epithelial-to-mesenchymal transition, (ii) reduced activity of prometastatic/proinflammatory transcription factors (GATA-1, GATA-2, early-growth-response-3/EGR3, signal transducer and activator of transcription-3/STAT-3), and (iii) decreased tumor-infiltrating monocytes while increasing tumor-infiltrating B cells. Drug treatment also significantly abrogated presurgical increases in serum IL6 and C-reactive protein levels, abrogated perioperative declines in stimulated IL12 and IFNγ production, abrogated postoperative mobilization of CD16− “classical” monocytes, and enhanced expression of CD11a on circulating natural killer cells. Conclusions: Perioperative inhibition of COX-2 and β-adrenergic signaling provides a safe and effective strategy for inhibiting multiple cellular and molecular pathways related to metastasis and disease recurrence in early-stage breast cancer. Clin Cancer Res; 23(16); 4651–61. ©2017 AACR.

In vivo suppression of NK cell cytotoxicity by stress and surgery: glucocorticoids have a minor role compared to catecholamines and prostaglandins.

Most in vitro and ex-vivo studies indicate a profound suppression of NK cell cytotoxicity (NKCC) by glucocorticoids; while catecholamines and prostaglandins were reported both to suppress and to enhance NKCC. However, methodological considerations hinder our ability to deduce from these findings to the impact of endogenous release of these factors on in vivo levels of NKCC and their implications to NK-dependent resistance to pathologies in living humans or animals. Here we used an in vivo approach that sensitively and specifically reflects NKCC in living F344 rats, based on lung clearance of NK-sensitive tumor cells (MADB106), and based on comparing effects between NK-intact and NK-depleted rats. To study the role of corticosterone, epinephrine, and prostaglandins, we administered these factors to rats, or antagonized their endogenous release following different stress paradigms or surgery. The results indicated that endogenous or exogenous elevated corticosterone levels can suppress in vivo NKCC levels, but only under some conditions, and mostly secondarily to the NK-suppressing impact of epinephrine. Specifically, corticosterone-induced NKCC suppression occurred (i) only under prolonged, but not short exposure to stress, and mainly in males; (ii) was smaller than the prominent impact of epinephrine; (iii) was mostly ascribed to corticosterone-induced potentiation of the effects of epinephrine or/and prostaglandins; and (iv) was completely abolished through antagonizing epinephrine or/and prostaglandins. Overall, these findings markedly limit the significance of stress/surgery-induced corticosterone release in the in vivo suppression of NKCC, and highlight the blockade of epinephrine or/and prostaglandins as effective and clinically feasible approaches to overcome such immuno-suppressive effects.

Perioperative treatment with the new synthetic TLR-4 agonist GLA-SE reduces cancer metastasis without adverse effects

The use of TLR agonists as an anti‐cancer treatment is gaining momentum given their capacity to activate various host cellular responses through the secretion of inflammatory cytokines and type‐I interferons. It is now also recognized that the perioperative period is a window of opportunity for various interventions aiming at reducing the risk of cancer metastases—the major cause of cancer related death. However, immune‐stimulatory approach has not been used perioperatively given several contraindications to surgery. To overcome these obstacles, in this study, we used the newly introduced, fully synthetic TLR‐4 agonist, Glucopyranosyl Lipid‐A (GLA‐SE), in various models of cancer metastases, and in the context of acute stress or surgery. Without exerting evident adverse effects, a single systemic administration of GLA‐SE rapidly and dose dependently elevated both innate and adaptive immunity in the circulation, lungs and the lymphatic system. Importantly, GLA‐SE treatment led to reduced metastatic development of a mammary adenocarcinoma and a colon carcinoma by approximately 40–75% in F344 rats and BALB/c mice, respectively, at least partly through elevating marginating‐pulmonary NK cell cytotoxicity. GLA‐SE is safe and well tolerated in humans, and currently is used as an adjuvant in phase‐II clinical trials. Given that the TLR‐4 receptor and its signaling cascade is highly conserved throughout evolution, our current results suggest that GLA‐SE may be a promising immune stimulatory agent in the context of oncological surgeries, aiming to reduce long‐term cancer recurrence.

The misleading nature of in vitro and ex vivo findings in studying the impact of stress hormones on NK cell cytotoxicity

In vitro and ex vivo studies assessing the impact of stress hormones on immune competence commonly replace the natural milieu of leukocytes with an artificial medium, excluding plasma factors, hormones, and cytokines. Given prevalent inconsistencies between in vitro, ex vivo, and in vivo findings, we studied whether such procedures could yield misleading outcomes regarding the impact of stress hormones on NK cell cytotoxicity (NKCC), using fresh human whole blood samples. We found that in the presence of plasma 10-30-fold higher concentrations of cortisol, epinephrine, and prostaglandin-E2 (PGE2) were required to reach suppression levels evident in the context of artificial medium. Importantly, whereas the NK suppressive effects of PGE2 occurred immediately and remained stable upon prolonged exposure, the suppressive effects of cortisol slowly increased over time. Last, to simulate the exclusion of stress factors in the ex vivo approach, we subjected whole blood to stress hormones (as occurs in vivo), and abruptly removed them. We found that the effects of epinephrine and PGE2 quickly disappeared, while the effects of cortisol persisted. Overall, these findings demonstrate the potential misleading nature of in vitro and ex vivo procedures, and specifically suggest that (i) the common in vitro findings of profound suppression of NKCC by stress hormones are overestimation of their direct effects expected in vivo; and (ii) the common ex vivo approach cannot reflect the direct in vivo suppressive effects of epinephrine and PGE2 on NKCC, while inflating the effects of glucocorticoids. Some of these fallacies may be circumvented by using non-delayed whole blood NKCC assays in humans.

Plasma IL-12 levels are suppressed in vivo by stress and surgery through endogenous release of glucocorticoids and prostaglandins but not catecholamines or opioids

IL-12 is a prominent Th1 differentiator and leukocyte activator. Ample studies showed suppression of IL-12 production by numerous stress factors, including prostaglandins, catecholamines, glucocorticoids, and opioids, but did so in vitro and in the context of artificial leukocyte activation, not simulating the in vivo setting. In a recent study we reported in vivo suppression of plasma IL-12 levels by behavioral stress and surgery. The current study aims to elucidate neuroendocrine mechanisms underlying this phenomenon in naïve F344 rats. To this end, both adrenalectomy and administration of specific antagonists were used, targeting the aforementioned stress factors. The results indicated that corticosterone and prostaglandins are prominent mediators of the IL-12-suppressing effects of stress and surgery, apparently through directly suppressing leukocyte IL-12 production. Following surgery, endogenous prostaglandins exerted their effects mainly through elevating corticosterone levels. Importantly, stress-induced release of epinephrine or opioids had no impact on plasma IL-12 levels, while pharmacological administration of epinephrine reduced plasma IL-12 levels by elevating corticosterone levels. Last, a whole blood in vitro study indicated that prostaglandins and corticosterone, but not epinephrine, suppressed IL-12 production in non-stimulated leukocytes, and only corticosterone did so in the context of CpG-C-induced IL-12 production. Overall, the findings reiterate the notion that results from in vitro or pharmacological in vivo studies cannot indicate the effects of endogenously released stress hormones under stress/surgery conditions. Herein, corticosterone and prostaglandins, but not catecholamines or opioids, were key mediators of the suppressive effect of stress and surgery on in vivo plasma IL-12 levels in otherwise naïve animals.

Resilience of the Immune System in Healthy Young Students to 30-Hour Sleep Deprivation with Psychological Stress

Objective: Young adults often encounter sleep deprivation and stressful events. Both have been separately reported to modulate immunity, and occasionally they occur simultaneously. We assessed the combined effects of these conditions on immune competence in healthy students. Methods: Twenty-three participants (mean age 24 years; SD 1.86; 14 females) were exposed to 30 h of sleep deprivation during which they conducted physiological, social and cognitive tasks. The control group consisted of 18 participants (mean age 23.67 years; SD 1.46; 11 females). All participants underwent cognitive and psychological evaluations at 10:00 AM, followed by blood and saliva collection, 3 days before sleep deprivation induction and on the morning following it. Immune/endocrine measures included blood counts of lymphocytes, granulocytes, monocytes and natural killer (NK) cells; levels of several cell surface markers; NK cytotoxicity; plasma levels of interleukin (IL)-6, IL-10, dehydroepiandrosterone and neuropeptide Y, and plasma and salivary cortisol levels. Results: Although the experimental protocol significantly elevated state anxiety and psychological dissociation levels, no effects were evident in any of the immunological/endocrine indices. In contrast, expected sex differences in immune measures were found, including significantly higher NK cytotoxicity and monocyte counts in males, validating the integrity of the measurements. Conclusions: The findings suggest resilience of the immune system to a combined sleep deprivation and stressful exposure in young adults, while previous studies reported immune perturbations following either of these conditions separately. These apparent contradictions might reflect differences in the study design or in the methodology used for immunological assessments, including the time of sample collection, the combination of sleep deprivation with stress and our in vivo assessment of cytokine levels.

PGE2 suppresses NK activity in vivo directly and through adrenal hormones: effects that cannot be reflected by ex vivo assessment of NK cytotoxicity.

Surgery can suppress in vivo levels of NK cell cytotoxicity (NKCC) through various mechanisms, including catecholamine-, glucocorticoid (CORT)-, and prostaglandin (PG)-mediated responses. However, PGs are synthesized locally following tissue damage, driving proinflammatory and CORT responses, while their systemic levels are often unaffected. Thus, we herein studied the role of adrenal factors in mediating in vivo effects of PGs on NKCC, using adrenalectomized and sham-operated F344 rats subjected to surgery or PGE(2) administration. In vivo and ex vivo approaches were employed, based on intravenous administration of the NK-sensitive MADB106 tumor line, and based on ex vivo assessment of YAC-1 and MADB106 target-line lysis. Additionally, in vitro studies assessed the kinetics of the impact of epinephrine, CORT, and PGE(2) on NKCC. The results indicated that suppression of NKCC by epinephrine and PGE(2) are short lasting, and cannot be evident when these compounds are removed from the in vitro assay milieu, or in the context of ex vivo assessment of NKCC. In contrast, the effects of CORT are long-lasting and are reflected in both conditions even after its removal. Marginating-pulmonary NKCC was less susceptible to suppression than circulating NKCC, when tested against the xenogeneic YAC-1 target line, but not against the syngeneic MADB106 line, which seems to involve different cytotoxicity mechanisms. Overall, these findings indicate that elevated systemic PG levels can directly suppress NKCC in vivo, but following laparotomy adrenal hormones mediate most of the effects of endogenously-released PGs. Additionally, the ex vivo approach seems limited in reflecting the short-lasting NK-suppressive effects of catecholamines and PGs.

The impact of surgical extent and sex on the hepatic metastasis of colon cancer

PurposeExtensive oncological surgeries were previously suggested to increase cancer recurrence rates. We herein studied the impact of different surgical procedures and sex on colorectal cancer liver metastasis, employing several tumor inoculation approaches in BALB/c mice.MethodsExperimental hepatic metastases of the syngeneic CT26 colorectal cancer line were induced either by intra-portal inoculation or intra-splenic inoculation, employing different tumor loads. Following intra-splenic inoculation, the entire spleen or an injected hemi-spleen was removed. Additionally, the magnitude of the surgical trauma accompanying the injection procedure was manipulated.ResultsIncreasing the surgical trauma by adding laparotomy or extending the length of the surgery and hypothermia did not significantly affect the number of liver metastases or liver weight for any of the injection methods and tumor loads. The development of metastasis was significantly greater in males than in females under all conditions studied—a difference not explained by the direct effects of sex hormones on in vitro CT26 proliferation or vitality.ConclusionConcurring with less controlled clinical observations, the surgical extensiveness did not significantly affect CT26 hepatic metastasis, potentially due to a ceiling effect of the surgical trauma on the metastatic process. The sexual dimorphism observed for the CT26 metastasis should be investigated in the context of surgical stress and considering anti-CT26 immunoreactivity.

Dexmedetomidine promotes metastasis in rodent models of breast, lung, and colon cancers

Background: Perioperative strategies can significantly influence long‐term cancer outcomes. Dexmedetomidine, an &agr;2‐adrenoceptor agonist, is increasingly used perioperatively for its sedative, analgesic, anxiolytic, and sympatholytic effects. Such actions might attenuate the perioperative promotion of metastases, but other findings suggest opposite effects on primary tumour progression. We tested the effects of dexmedetomidine in clinically relevant models of dexmedetomidine use on cancer metastatic progression. Methods: Dexmedetomidine was given to induce sub‐hypnotic to sedative effects for 6–12 h, and its effects on metastasis formation, using various cancer types, were studied in naïve animals and in the context of stress and surgery. Results: Dexmedetomidine increased tumour‐cell retention and growth of metastases of a mammary adenocarcinoma (MADB 106) in F344 rats, Lewis lung carcinoma (3LL) in C57BL/6 mice, and colon adenocarcinoma (CT26) in BALB/c mice. The metastatic burden increased in both sexes and in all organs tested, including lung, liver, and kidney, as well as in brain employing a novel external carotid‐artery inoculation approach. These effects were mediated through &agr;2‐adrenergic, but not &agr;1‐adrenergic, receptors. Low sub‐hypnotic doses of dexmedetomidine were moderately beneficial in attenuating the deleterious effects of one stress paradigm, but not of the surgery or other stressors. Conclusions: The findings call for mechanistic translational studies to understand these deleterious effects of dexmedetomidine, and warrant prospective clinical trials to assess the impact of perioperative dexmedetomidine use on outcomes in cancer patients.

Acute and innocuous CpG-C immune stimulation potentiates host resistance to hepatic metastases of colon cancer and protects against immunosuppressive effects of surgery

Liver metastases are a major cause of cancer-related mortality. Marginating-hepatic (MH)-NK cells are strategically located in the liver sinusoids to physically interact and lyse circulating tumor cells. In cancer patients, the short peri-operative period is now recognized as critical in determining the progression of remaining malignant disease into established metastases. However, the benefits of immune stimulation have rarely been studied peri-operatively, given the short time frame and contraindications to surgery. To overcome these obstacles, we herein employed a new synthetic TLR-9 agonist, CpG-C, which has minimal adverse effects in rodents and humans. Our results indicated that a single pre-operative CpG-C administration tripled MH-NK cell numbers, and dramatically increased their per-cell NK cytotoxicity against the standard YAC-1 and the syngeneic CT26 colon cancer cell lines. Furthermore, CpG-C treatment protected mice from laparotomy-induced immune suppression, based on examining MH-NK cytotoxicity levels and several molecular markers of NK-cell function, including NKp46, CD49b, CD11b, and NKG2A. Importantly, this short and innocuous CpG-C treatment dramatically reduced the number of hepatic metastases developed 3-weeks following surgical inoculation of CT26 through the hepatic portal vein. These beneficial effects are mediated through activation of NK cells, as NK depletion by anti-asialo GM1 completely abrogated them. Overall, this approach is feasible in cancer patients, and may introduce a new peri-operative intervention to improve long-term cancer outcomes during the critical and unexploited peri-operative time frame.