Michiko Imamura

Contribution of TIR domain-containing adapter inducing IFN-β-mediated IL-18 release to LPS-induced liver injury in mice

BACKGROUND/AIMS After treatment with heat-killed Propionibacterium acnes mice show dense hepatic granuloma formation. Such mice develop liver injury in an interleukin (IL)-18-dependent manner after challenge with a sublethal dose LPS. As previously shown, LPS-stimulated Kupffer cells secrete IL-18 depending on caspase-1 and Toll-like receptor (TLR)-4 but independently of its signal adaptor myeloid differentiation factor 88 (MyD88), suggesting importance of another signal adaptor TIR domain-containing adapter inducing IFN-beta (TRIF). Nalp3 inflammasome reportedly controls caspase-1 activation. Here we investigated the roles of MyD88 and TRIF in P. acnes-induced hepatic granuloma formation and LPS-induced caspase-1 activation for IL-18 release. METHODS Mice were sequentially treated with P. acnes and LPS, and their serum IL-18 levels and liver injuries were determined by ELISA and ALT/AST measurement, respectively. Active caspase-1 in LPS-stimulated Kupffer cells was determined by Western blotting. RESULTS Macrophage-ablated mice lacked P. acnes-induced hepatic granuloma formation and LPS-induced serum IL-18 elevation and liver injury. Myd88(-/-) Kupffer cells, but not Trif(-/-) cells, exhibited normal caspase-1 activation upon TLR4 engagement in vitro. Myd88(-/-) mice failed to develop hepatic granulomas after P. acnes treatment and liver injury induced by LPS challenge. In contrast, Trif(-/-) mice normally formed the hepatic granulomas, but could not release IL-18 or develop the liver injury. Nalp3(-/-) mice showed the same phenotypes of Trif(-/-) mice. CONCLUSIONS Propionibacterium acnes treatment MyD88-dependently induced hepatic granuloma formation. Subsequent LPS TRIF-dependently activated caspase-1 via Nalp3 inflammasome and induced IL-18 release, eventually leading to the liver injury.

The TLR4/TRIF-Mediated Activation of NLRP3 Inflammasome Underlies Endotoxin-Induced Liver Injury in Mice

Administration of heat-killed Propionibacterium acnes renders mice highly susceptible to LPS. After LPS challenge P. acnes-primed mice promptly show hypothermia, hypercoagulation (disseminated intravascular coagulation), elevation of serum proinflammatory cytokine levels, and high mortality. The surviving mice develop liver injury. As previously reported, IL-18 plays a pivotal role in the development of this liver injury. Many cell types including macrophages constitutively store IL-18 as biologically inactive precursor (pro) form. Upon appropriate stimulation exemplified by TLR4 engagement, the cells secrete biologically active IL-18 by cleaving pro-IL-18 with caspase-1. Caspase-1 is also constitutively produced as a zymogen in macrophages. Recently, NLRP3, a cytoplasmic pathogen sensor, has been demonstrated to be involved in the activation of caspase-1. Here, we review the molecular mechanisms for the liver injuries, particularly focusing on the TLR4/NLRP3-mediated caspase-1 activation process, with a brief introduction of the mechanism underlying P. acnes-induced sensitization to LPS.

Mechanisms of estrogen receptor-α upregulation in breast cancers.

The most critical step for initiation and progression of estrogen receptor-α (ERα)-positive breast cancers is thought to be upregulation of ERα expression. There are several factors involved in this mechanism, i.e., increased promoter activity of the ERα gene (ESR1) at the transcriptional level, ESR1 gene amplification, and diminished degradation of ERα protein through ubiquitination and proteasomal pathways. Mediating these factors, ERα protein levels seem to be controlled, although the details of the mechanism remain to be clarified. In addition, for upregulation of estrogen signaling, functional changes in its action in cancer cells originating from normal epithelial cells, i.e., estrogen stimulation, which then leads to proliferation of ERα-positive cancer cells, has been recognized, but this action has not been observed in normal epithelial cells. These alterations are therefore likely to contribute to the pathogenesis of ERα-positive breast cancers.

High Ki-67 Expression and Low Progesterone Receptor Expression Could Independently Lead to a Worse Prognosis for Postmenopausal Patients With Estrogen Receptor-Positive and HER2-Negative Breast Cancer

UNLABELLED We examined the prognostic significance of progesterone receptor (PgR) expression in immunohistochemical-based luminal subtypes defined by Ki-67 expression, taking menopausal status into consideration. The study included 327 surgically removed estrogen receptor-positive and human epidermal growth factor receptor 2-negative breast cancers. High Ki-67 expression (> 15%) and low PgR expression (£ 20%) were significant independent factors resulting in worse distant relapse-free survival. This association was observed in postmenopausalwomen but not in premenopausal women. BACKGROUND Accurate classification of luminal A and luminal B characteristics of estrogen receptor (ER)-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer is considered clinically important for determining effective adjuvant treatment. Although Ki-67 expression has been identified as an essential constituent for this classification, the role of progesterone receptor (PgR) expression has yet to be fully elucidated. Because PgR expression is influenced by the estrogen milieu, we examined the prognostic significance of PgR expression in immunohistochemical (IHC)-based luminal subtypes defined by Ki-67 expression, taking menopausal status into consideration. MATERIALS AND METHODS We examined 327 surgically removed ER(+) and HER2(-) breast cancer specimens. ER, PgR, and Ki67 expression was determined IHC for semiquantitative measurement. We used 1%, 20%, and 15% as the cutoff value for ER, PgR, and Ki-67, respectively. RESULTS Breast cancer with low PgR (≤ 20%) expression was significantly associated with postmenopausal status, a large tumor size, and low ER expression. The low PgR expression subset had significantly worse distant relapse-free survival (DRFS) than the high PgR expression subset (P = .0067). This association was observed consistently in postmenopausal women but not in the premenopausal women. Multivariate analysis demonstrated that high Ki-67 expression (hazard ratio [HR], 3.80; 95% confidence interval [CI], 1.57-10.58; P = .003) and low PgR expression (HR, 2.54; 95% CI, 1.08-6.40; P = .038) were significant independent factors affecting DRFS. CONCLUSION Low PgR expression was independently associated with a poorer prognosis for ER(+) and HER2(-) breast cancer. Determination of PgR expression combined with that of Ki-67 could thus improve the accuracy of IHC-based classification of luminal A and luminal B breast cancer, especially for postmenopausal women.

Contribution of IL-18 to eosinophilic airway inflammation induced by immunization and challenge with Staphylococcus aureus proteins

We previously reported that intranasal challenge with ovalbumin (OVA) plus IL-18 induces airway hyperresponsiveness (AHR) and eosinophilic airway inflammation in mice with OVA-specific T(h)1 cells. These two conditions can be prevented by neutralizing anti-IFN-gamma and anti-IL-13 antibodies, respectively. The mice develop AHR and eosinophilic airway inflammation after challenge with OVA plus LPS instead of IL-18 and endogenous IL-18 is known to be involved. In contrast, IL-18 does not facilitate these changes in mice possessing OVA-specific T(h)2 cells. Here, we investigated whether IL-18 is involved in the development of asthma in mice immunized and challenged with bacterial proteins. Upon intranasal exposure to protein A (SpA) derived from Staphylococcus aureus, mice immunized with SpA exhibited AHR and peribronchial eosinophilic inflammation if IFN-gamma or IL-13 were present, respectively. The CD4(+) T cells from draining lymph nodes (DLNs) of the SpA-immunized and -challenged mice produced a robust IFN-gamma and IL-13 in response to immobilized anti-CD3 antibodies. Treatment with neutralizing anti-IL-18 antibodies prevented asthmatic inflammation concomitant with their impaired potential to express IFN-gamma and IL-13. Furthermore, naive mice that received the CD4(+) T cells from DLNs of SpA-immunized mice developed airway inflammation depending upon the presence of IL-18. Immunodeficient mice that received human PBMCs, which had been stimulated with SpA in vitro, developed dense peribronchial accumulation of human CD4(+) T cells upon SpA challenge. Neutralizing anti-human IL-18 antibodies protected against this airway inflammation. These results suggest the importance of IL-18 for the development of asthmatic inflammation associated with airway exposure to bacterial proteins.

Activation of mTOR/S6K But Not MAPK Pathways Might Be Associated With High Ki-67, ER+, and HER2− Breast Cancer

UNLABELLED We determined the activation of the phosphoinositide 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) signaling pathways in 108 cases of estrogen receptor-positive and human epidermal growth factor receptor 2-negative breast cancer with high and low Ki-67 expression. The expression levels of Ki-67, p53, phosphorylated MAPK (pMAPK), and protein S6 (pS6; downstream molecule of PI3K/Akt/mammalian target of rapamycin/S6 kinase pathway) were determined immunohistochemically. pS6 positivity, but not pMAPK positivity, was significantly associated with the high Ki-67 expression subset. BACKGROUND Evaluation of luminal A and luminal B characteristics of estrogen receptor (ER)-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer is considered important. Although the phosphoinositide 3 kinase (PI3K) and mitogen-activated protein kinase (MAPK) signaling pathways are thought to be involved in the luminal B subtype, the details of their contribution to breast cancer remain unclear. MATERIALS AND METHODS We determined the activation of these pathways (phosphorylated MAPK [pMAPK] and protein S6 [pS6; a downstream molecule of PI3K/Akt/mammalian target of rapamycin (mTOR)/S6 kinase (S6K)]) in 108 ER(+), HER2(-) breast cancer cases with high and low Ki-67 expression. The ER, progesterone receptor (PgR), Ki-67, p53 expression levels were also determined immunohistochemically. The cutoff value for Ki-67 was set at 15%. RESULTS A significantly greater percentage of cancer cases with high Ki-67 expression showed pS6 positivity than did those with low Ki-67 expression (53.2% vs. 19.7%; P = .0003). No significant differences were found between the cases with high and low expression levels were detected for p53 (23.4% vs. 11.5%; P = .12) or pMAPK (36.2% vs. 34.4%; P = .85) positivity. Multivariate analysis showed that pS6 positivity (odds ratio 5.16, 95% confidence interval 1.95-13.63; P = .0009), nuclear grade 2 and 3, and low PgR expression (≤ 20%) were independently associated with the high Ki-67 subset. CONCLUSION From our findings, we have concluded that the pS6 expression level is associated with the characteristics of breast cancer with high Ki-67 expression. Because these associations were observed, irrespective of menopausal status, the biologic difference seems to be less affected by estrogen signaling than by activation of S6 protein, especially in terms of proliferation. Our findings have also indicated that targeting the mTOR/S6K pathway might be a useful strategy for the treatment of ER(+)/HER2(-) breast cancer with high Ki-67 expression.

High levels of serum CA15-3 and residual invasive tumor size are associated with poor prognosis for breast cancer patients with non-pathological complete response after neoadjuvant chemotherapy: FUJIMOTO et al.

To identify surrogate markers for prognosis of breast cancer patients with non‐pathological complete response (non‐pCR) to neoadjuvant chemotherapy (NAC), our investigation focused on the serum levels of carcinoembryonic antigen (CEA) and carbohydrate antigen (CA15‐3) as well as clinicopathological factors both before and after NAC.

Significant Association Between Low Baseline Neutrophil-to-Lymphocyte Ratio and Improved Progression-free Survival of Patients With Locally Advanced or Metastatic Breast Cancer Treated With Eribulin But Not With Nab-Paclitaxel

Introduction Although eribulin and nab‐paclitaxel are chemotherapy agents widely used for locally advanced or metastatic breast cancer (MBC), their predictive factors remain unknown. Because the absolute neutrophil‐to‐lymphocyte ratio (NLR) is a significant prognostic factor for early‐stage breast cancer, we investigated its usefulness in terms of the eribulin or nab‐paclitaxel treatment efficacy for MBC. Patients and Methods A total of 85 patients with MBC treated with eribulin (n = 59) or nab‐paclitaxel (n = 26) were recruited. NLR values were collected at baseline, after 1 cycle, after 2 cycles, and at the end of treatment. The NLR cutoff value was set at 3. Results The progression‐free survival (PFS) of patients with an NLR < 3 at baseline (median, 242 days; n = 24) was significantly better than that of patients with an NLR of ≥ 3 (median, 98 days; n = 35; hazard ratio, 0.37, 95% confidence interval, 0.18‐0.71; P = .0032). Similarly, the overall survival was marginally significantly better in patients with an NLR < 3 who were treated with eribulin (P = .058). However, the NLR was not significantly associated with PFS or overall survival for patients treated with nab‐paclitaxel. No significant association was found between the NLR during treatment and PFS in the eribulin group. The significance of the NLR for the efficacy of eribulin was consistent, irrespective of estrogen receptor status, previous anthracycline or endocrine use, and the number of previous chemotherapy regimens. Conclusion A low NLR at baseline was significantly associated with improved PFS in patients treated with eribulin but not in those treated with nab‐paclitaxel. Therefore, the baseline NLR might be clinically useful for selecting patients who would benefit from eribulin. Micro‐Abstract Both eribulin and nab‐paclitaxel are widely used and effective chemotherapy agents for metastatic breast cancer; however, their predictive factors remain unknown. The usefulness of the neutrophil‐to‐lymphocyte ratio (NLR) in terms of treatment efficacy was investigated. We observed that a low NLR at baseline might be a significant indicator of improved outcomes for patients treated with eribulin but not with nab‐paclitaxel.

Predictive impact of absolute lymphocyte counts for progression-free survival in human epidermal growth factor receptor 2-positive advanced breast cancer treated with pertuzumab and trastuzumab plus eribulin or nab-paclitaxel

AbstractsBackgroundAlthough peripheral blood-based parameters (PBBPs) are reported as prognostic indicators in patients with breast cancers, their utility has not been studied in human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer (ABC). Tumor-infiltrating lymphocytes (TILs) might be a predictive factor in patients with HER2-positive ABC treated with pertuzumab and trastuzumab (PT) plus docetaxel. We aimed to evaluate whether PBBPs could have predictive value in HER2-positive ABC treated with pertuzumab and trastuzumab (PT) combined with eribulin (ERI) or nab-paclitaxel (Nab-PTX).MethodsData from 51 patients included in two single-arm, phase II trials were included in this retrospective-prospective study; the ERI + PT (N = 30) and Nab-PTX + PT (N = 21) combinations were registered under clinical trials number UMIN000012375 and UMIN000006838, respectively. We assessed PBBPs using prospectively collected data and investigated the association with progression-free survival (PFS); we evaluated absolute lymphocyte count (ALC), neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR). The cutoff values for ALC, NLR, and PLR were set at 1000 or 1500 cells/μL, 2, and 250, respectively.ResultsPFS was significantly improved in patients with ALC ≥1500/μL compared to those with ALC 1000–, <1500/μL or ALC < 1000/μL (P = 0.0106). High baseline ALC was significantly associated with improved PFS (≥1500/μL; hazard ratio [HR]: 0.3715; 95% confidence interval [CI]: 0.1735–0.7955; P = 0.0108). In contrast, improved PFS was not significantly associated with NLR or PLR. Improved PFS in patients with ALC ≥1500/μL was observed irrespective of visceral metastasis or chemotherapy regimen.ConclusionsOur results showed that baseline ALC was a predictive factor for PFS in HER2-positive ABC treated with PT irrespective of combined chemotherapy regimen. Anti-tumor effects might be mediated not only by the tumor microenvironment, but also by systemic peripheral circulating lymphocytes. Baseline systemic parameters such as peripheral lymphocyte count might be beneficial in addition to disease extent for predicting the efficacy of PT treatment.Trial registrationUMIN000012375, registration date: 21NOV2013, and UMIN000006838, registration date: 6DEC2011.

C-reactive Protein Level on Postoperative Day One is Associated with Chronic Postsurgical Pain After Mastectomy

Background C-reactive protein (CRP) is an acute phase reactant released in response to inflammation or tissue injury. Inflammation is one of the pathogenic factors related to transition from acute postsurgical pain (APSP) to chronic postsurgical pain (CPSP). Although several risk factors are reportedly associated with CPSP, the effects of CRP levels on CPSP have not been examined. Objectives The present study investigated the relationship between perioperative risk factors, including CRP levels on postoperative day one and CPSP, in patients undergoing mastectomy. Methods Preoperative anxiety and depression levels were evaluated in female patients undergoing mastectomy under general anesthesia, with or without peripheral nerve block. Patients with chronic preoperative pain and/or preoperative breast pain were excluded. The intensity of postoperative pain was prospectively examined one and six days, and three and twelve months after surgery using a numerical rating scale (NRS). Results The current researchers conducted univariate and multivariate linear regression analyses to explore risk factors for CPSP in 36 patients. Patient demographics, preoperative psychological states, and anesthetic managements showed no relationship with CPSP. On the other hand, pain intensity of APSP and CRP levels on postoperative day one was significantly associated with the pain intensity of CPSP. Conclusions Postoperative CRP level is likely to be associated with the development of CPSP after mastectomy.