Shear stress in the intervillous space promotes syncytial formation of iPS cells-derived trophoblasts†

The intervillous space of human placenta is filled with maternal blood, and villous trophoblasts are constantly exposed to the shear stress generated by maternal blood pressure and flow throughout the entire gestation period. However, the effects of shear stress on villous trophoblasts and their biological significance remain unknown. Here, using our recently established naïve human pluripotent stem cells-derived cytotrophoblast stem cells (nCTs) and a device that can apply arbitrary shear stress to cells, we investigated the impact of shear stress on early-stage trophoblasts. After 72 h of exposure to 10 dyn/cm2 shear stress, nCTs became fused and multinuclear, and mRNA expression of the syncytiotrophoblast (ST) markers, such as glial cell missing 1, endogenous retrovirus group W member 1 envelope, chorionic gonadotropin subunit beta 3, syndecan 1, pregnancy specific beta-1-glycoprotein 3, placental growth factor, and solute carrier family 2 member 1 were significantly upregulated compared to static conditions. Immunohistochemistry showed that shear stress increased fusion index, human chorionic gonadotropin secretion, and human placental lactogen secretion. Increased microvilli formation on the surface of nCTs under flow conditions was detected using scanning electron microscopy. Intracellular cyclic adenosine monophosphate significantly increased under flow conditions. Moreover, transcriptome analysis of nCTs subjected to shear stress revealed that shear stress upregulated ST-specific genes and downregulated CT-specific genes. Collectively, these findings indicate that shear stress promotes the differentiation of nCTs into ST.

Homologous Recombination Deficiency Unrelated to Platinum and PARP Inhibitor Response in Cell Line Libraries

While large publicly available cancer cell line databases are invaluable for preclinical drug discovery and biomarker development, the association between homologous recombination deficiency (HRD) and drug sensitivity in these resources remains unclear. In this study, we comprehensively analyzed molecular profiles and drug screening data from the Cancer Cell Line Encyclopedia. Unexpectedly, gene alterations in BRCA1/2 or homologous recombination-related genes, HRD scores, or mutational signature 3 were not positively correlated with sensitivity to platinum agents or PARP inhibitors. Rather, higher HRD scores and mutational signature 3 were significantly associated with resistance to these agents in multiple assays. These findings were consistent when analyzing exclusively breast and ovarian cancer cell lines and when using data from the COSMIC Cell Line Project. Collectively, the existing data from established cancer cell lines do not reflect the expected association between HRD status and drug response to platinum agents and PARP inhibitors in clinical tumors. This discrepancy may extend to other tumor characteristics, highlighting the importance of recognizing potential limitations in cell line data for researchers.

Time-Dependent Changes in Risk of Progression During Use of Bevacizumab for Ovarian Cancer

Importance

Although bevacizumab has been used in the treatment of ovarian cancer, its optimal use is unknown.

Objective

To investigate time-dependent changes in the outcomes of bevacizumab therapy.

Design, Setting, and Participants

This cohort study was conducted using published data from 7 previous randomized phase 3 clinical trials with bevacizumab (ICON7, GOG-0218, BOOST, GOG-0213, OCEANS, AURERIA, and MITO16B) from January 10 to January 31, 2023. From 2 ancillary analyses of the ICON7 trial with individual patient data and tumor gene expression profiles, an ICON7-A cohort was generated comprising 745 cases. From other studies, published Kaplan-Meier curves were graphically analyzed.

Exposures

Bevacizumab treatment vs placebo or no treatment.

Main Outcomes and Measures

Restricted mean survival time and relative risk of progression at a given time point between bevacizumab treatment and control groups.

Results

In the ICON7-A cohort (n = 745), restricted mean survival analysis showed that bevacizumab treatment (n = 384) had significantly better progression-free survival (PFS) than the control (n = 361) before bevacizumab discontinuation (restricted mean survival time ratio, 1.08; 95% CI, 1.05-1.11; P < .001), but had significantly worse PFS after bevacizumab discontinuation (0.79; 95% CI, 0.69-0.90; P < .001), showing rebound. In a post hoc analysis, the rebound was similarly observed both in homologous recombination deficiency (HRD) (before, 1.05; 95% CI, 1.02-1.09; P < .001; after, 0.79; 95% CI, 0.63-0.98; P = .04) and non-HRD tumors (before, 1.08; 95% CI, 1.03-1.15; P < .001; after, 0.71; 95% CI, 0.56-0.90; P < .001) of the serous subtype, but not in the nonserous subtype (before, 1.11; 95% CI, 1.05-1.18; P < .001; after, 0.94; 95% CI, 0.78-1.15; P = .57). In Kaplan-Meier curve image-based analysis, the trend of rebound effect was consistently observed in the overall ICON7 and GOG-0218 cohorts and their subgroups stratified by prognostic factors, homologous recombination-associated mutations, and chemotherapy sensitivity. In contrast, no such trend was observed in the studies GOG-0213, OCEANS, AURERIA, and MITO16B, in which patients who experienced relapse received bevacizumab until progression.

Conclusions and Relevance

In ovarian cancer, bevacizumab may reduce progression for approximately 1 year after initiation, but discontinuation may increase subsequent progression in the serous subtype regardless of HRD status. The results suggest that in the first-line treatment, bevacizumab may be more beneficial in patients with a shorter prognosis who are less likely to experience the rebound outcome.

Imiquimod for Cervical and Vaginal Intraepithelial Neoplasia: A Systematic Review and Meta-analysis

OBJECTIVE

To evaluate the treatment efficacy and the risk of adverse events of imiquimod for cervical intraepithelial neoplasia (CIN) and vaginal intraepithelial neoplasia (VAIN), compared with placebo or no intervention.

DATA SOURCES

We searched Cochrane, PubMed, ISRCTN registry, ClinicalTrials.gov , and the World Health Organization International Clinical Trials Registry Platform up to November 23, 2022.

METHODS OF STUDY SELECTION

We included randomized controlled trials and prospective nonrandomized studies with control arms that investigated the efficacy of imiquimod for histologically confirmed CIN or VAIN. The primary outcomes were histologic regression of the disease (primary efficacy outcome) and treatment discontinuation due to side effects (primary safety outcome). We estimated pooled odds ratios (ORs) of imiquimod, compared with placebo or no intervention. We also conducted a meta-analysis of the proportions of patients with adverse events in the imiquimod arms.

TABULATION, INTEGRATION, AND RESULTS

Four studies contributed to the pooled OR for the primary efficacy outcome. An additional four studies were available for meta-analyses of proportions in the imiquimod arm. Imiquimod was associated with increased probability of regression (pooled OR 4.05, 95% CI 2.08-7.89). Pooled OR for CIN in the three studies was 4.27 (95% CI 2.11-8.66); results of one study were available for VAIN (OR, 2.67, 95% CI 0.36-19.71). Pooled probability for primary safety outcome in the imiquimod arm was 0.07 (95% CI 0.03-0.14). The pooled probabilities (95% CI) of secondary outcomes were 0.51 (0.20-0.81) for fever, 0.53 (0.31-0.73) for arthralgia or myalgia, 0.31 (0.18-0.47) for abdominal pain, 0.28 (0.09-0.61) for abnormal vaginal discharge or genital bleeding, 0.48 (0.16-0.82) for vulvovaginal pain, and 0.02 (0.01-0.06) for vaginal ulceration.

CONCLUSION

Imiquimod was found to be effective for CIN, whereas data on VAIN were limited. Although local and systemic complications are common, treatment discontinuation is infrequent. Thus, imiquimod is potentially an alternative therapy to surgery for CIN.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42022377982.

Abstract 128: Clonal expansion with driver mutations in normal human endometrium

Introduction: The epithelial cells of the endometrium undergo rapid proliferation and shedding each month under the influence of estrogen and progesterone. Recent studies have demonstrated pervasive driver mutations in the endometrium with ageing. However, previous observations have been limited to the microscopic scale, and it is still unclear how clonal expansion occurs over the entire endometrium and what driver mutations are responsible therein. To address these issues, we performed multisampling of the endometrium with extensive spatial mapping.

Methods: We collected multiple endometrial glands from normal endometrium in a 5mm lattice in 19 patients who underwent hysterectomy (3-31 samples per case), followed by DNA extraction, detected somatic mutations by whole exome sequencing, to identify large clones that spread across samples based on shared mutations.

Results: In total, 216 bulk endometrial glands were analyzed. The number of detected somatic mutations per sample ranged from 6 to 98 (mean±SD: 37.8±16.0), and most of the samples had at least one known driver gene mutation (mean±SD: 4.38±2.27). The mutational signature analysis revealed the predominance of the age-related SBS1 and SBS5 signatures. dN/dS analysis identified 21 genes that were positively selected in normal endometrium, including PIK3CA, PIK3R1, KRAS, PPP2R1A, ARHGAP35, and FBXW7, most of which are also known as driver genes for endometrial cancer. The number of mutations and their frequency for each driver gene did not differ by background diseases: endometriosis, endometriosis-associated ovarian cancer and other non-endometrial related diseases. We found clones showing a large expansion involving multiple samples in 8 cases, most of which harbored one or more driver mutations, such as PIK3CA and KRAS. The size of the largest clone carrying a KRAS mutation, which was found in a 32-year-old woman with cervical cancer, spanned as long as 10 mm in diameter. This suggests that clonal expansion in the endometrium could be very rapid even in healthy women, which contrasts to the observations that clonal expansion in other organs is usually seen in aged individuals.

Conclusion: We confirmed the high frequency of driver mutations in the normal endometrium, most of which overlapped to those found in endometrial cancers, suggesting that these driver genes are involved in the early phase of the development in the endometrial cancer. Some of the driver-mutated clones expanded in macroscopic size. Our findings provide an interesting insight into the clonal structure and underlying genetic variation in the normal endometrium.

Citation Format: Koichi Watanabe, Nobuyuki Kakiuchi, Shiro Takamatsu, Sachiko Kitamura, Mana Taki, Koji Yamanoi, Ryusuke Murakami, Ken Yamaguchi, Junzo Hamanishi, Hiroko Tanaka, Satoru Miyano, Masaki Mandai, Seishi Ogawa. Clonal expansion with driver mutations in normal human endometrium [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 128.

Prognostic relevance of HRDness gene expression signature in ovarian high-grade serous carcinoma; JGOG3025-TR2 study

BACKGROUND

This study aimed to evaluate the homologous recombination repair pathway deficiency (HRD) in ovarian high-grade serous carcinoma (HGSC).

METHODS

In the ovarian cancer data from The Cancer Genome Atlas, we identified genes differentially expressed between tumours with and without HRD genomic scars and named these genes "HRDness signature". We performed SNP array, RNA sequencing, and methylation array analyses on 274 HGSC tumours for which targeted sequencing of 51 genes and clinical data were available to generate JGOG3025-TR2 dataset. The HRDness signature was tested on external datasets, including the JGOG3025-TR2 cohort, by computational scoring and machine-learning prediction.

RESULTS

High scores and positive predictions of the HRDness signature were significantly associated with BRCA alterations, genomic scar scores, and better survival. On the other hand, among cases with high scores and/or positive predictions, those with BRCA1 methylation showed poorer survival. In the JGOG3025-TR2 cohort, HRD status was significantly associated with the use of olaparib after relapse and progression-free survival after its initiation.

CONCLUSIONS

The HRDness gene expression signature is associated with a good prognosis, while BRCA1 methylation is associated with a poor prognosis. The newly generated JGOG3025-TR2 dataset will be useful in future HGSC studies.

Homologous Recombination Inquiry Through Ovarian Malignancy Investigations: JGOG3025 study

TCGA network has clarified that approximately 50% of high-grade serous ovarian cancers show homologous recombination deficiency (HRD). However, the frequency of HRD in Japanese patients with ovarian cancer remains unclear. We aimed to identify the frequency of HR-associated gene mutations in Japanese patients with ovarian cancer. The JGOG3025 study is a multicenter collaborative prospective observational study involving 65 study sites throughout Japan. We recruited 996 patients who were clinically diagnosed with ovarian cancer before surgery from March 2017 to March 2019, and 701 patients were eligible according to the criteria. We used frozen tumor tissues to extract DNA and performed next generation sequencing for 51 targeted genes (including 29 HR-associated genes) in 701 ovarian cancers (298 high-grade serous cases, 189 clear cell cases, 135 endometrioid cases, 12 mucinous cases, 3 low-grade serous cases, and 64 others). HRD was defined as positive when at least one HR-associated gene was mutated. The frequencies of HRD and tumor BRCA1/2 mutations were 45.2% (317/701) and 18.5% (130/701), respectively, in the full analysis set. Next, we performed multivariate Cox proportional hazards regression analysis for progression-free survival (PFS) and overall survival (OS). Advanced-stage ovarian cancer patients with HRD had adjusted hazard ratios of 0.72 (95% CI, 0.55-0.94) and 0.57 (95% CI, 0.38-0.86) for PFS and OS, respectively, compared to those without HRD (p = 0.016 and 0.007). Our study demonstrated that mutations in HR-associated genes were associated with prognosis. Further studies are needed to investigate the prognostic impact of each HR-associated gene in ovarian cancer.

Mutation burden-orthogonal tumor genomic subtypes delineate responses to immune checkpoint therapy

Background

In cancer therapy, higher-resolution tumor-agnostic biomarkers that predict response to immune checkpoint inhibitor (ICI) therapy are needed. Mutation signatures reflect underlying oncogenic processes that can affect tumor immunogenicity, and thus potentially delineate ICI treatment response among tumor types.

Methods

Based on mutational signature analysis, we developed a stratification for all solid tumors in The Cancer Genome Atlas (TCGA). Subsequently, we developed a new software (Genomic Subtyping and Predictive Response Analysis for Cancer Tumor ICi Efficacy, GS-PRACTICE) to classify new tumors submitted to whole-exome sequencing. Using existing data from 973 pan-cancer ICI-treated cases with outcomes, we evaluated the subtype-response predictive performance.

Results

Systematic analysis on TCGA samples identified eight tumor genomic subtypes, which were characterized by features represented by smoking exposure, ultraviolet light exposure, APOBEC enzyme activity, POLE mutation, mismatch repair deficiency, homologous recombination deficiency, genomic stability, and aging. The former five subtypes were presumed to form an immune-responsive group acting as candidates for ICI therapy because of their high expression of immune-related genes and enrichment in cancer types with FDA approval for ICI monotherapy. In the validation cohort, the samples assigned by GS-PRACTICE to the immune-reactive subtypes were significantly associated with ICI response independent of cancer type and TMB high or low status.

Conclusions

The new tumor subtyping method can serve as a tumor-agnostic biomarker for ICI response prediction and will improve decision making in cancer treatment.

Abstract 5261: Development of a computational algorithm to detect fatigue of gynecologic cancer patients using lifelogs

The improvement of the quality of life (QOL) of gynecological cancer patients is a critical purpose in cancer treatment. At present, there is no other methodology to evaluate QOL other than patients reported outcomes using QOL questionnaires. Therefore, management of QOL is not performed clinically because there is no objective and easy method to evaluate QOL. In this study, we extracted the worst symptom of QOL in gynecological cancer patients and examined whether QOL can be evaluated by lifelogs objectively.

Lifelogs (diets, sleep duration, the number of steps, pulse rate, voice, and so on) and QOL questionnaires (EORTC-qlq-c30, PHQ9, and so on) were collected from 139 gynecological cancer patients at our hospital using mobile applications. Scales of symptoms and functions were calculated from EORTC-qlq-c30. Logistic regression analyses and calculation of feature impact in the predictive model depicting receiver operating characteristic (ROC) curve were performed to extract symptoms and functions that contributed most to global health status (GHS) indicating a general QOL status. Fatigue-related metabolites in patient serum were measured by ELISA. Correlations between each lifelog, fatigue scale, and fatigue-related metabolites were examined. A computational model to detect high fatigue scale status was developed using lifelogs.

The fatigue scale was the highest among all treatment periods. The fatigue scale, appetite loss scale, and physical functioning scale were symptoms that deteriorate QOL frequently in gynecologic cancer patients (odds ratio: 0.9708, 0.9797, and 1.0374, respectively; 95% CI: 0.9493 to 0.9927, 0.9677 to 0.9919, and 1.0155 to 1.0597, respectively). ROC curve indicated that an accurate prediction of GHS using scales of symptoms and functions (area under the curve, AUC: 0.85). From the scales of symptoms and functions, the fatigue scale showed the highest feature impact to predict GSH. Several lifelogs were significantly correlated with fatigue scores (p&lt;0.05, r=-0.25 to -0.15 for each), and with the blood concentration of fatigue-related metabolites (p&lt;0.05, r=-0.44 to -0.37 for each). A computational algorithm using the fatigue-related lifelogs was successful to detect high fatigue score status (AUC=0.79). We found that two cases with persistent high fatigue scores and a low fatigue-related lifelog during chemotherapy led to depression and depressive relapse.

In summary, fatigue is a significant problem contributing to the decline in QOL of gynecological cancer patients. Fatigue can be monitored and diagnosed using digital data using lifelogs. These findings lead to the development of future management strategies of QOL for cancer patients.

Citation Format: Ken Yamaguchi, Nozomi higashiyama, Akihiko Ueda, Shiro Takamatsu, Masayo Ukita, Mana Taki, Koji Yamanoi, Junzo Hamanishi, Masaki Mandai. Development of a computational algorithm to detect fatigue of gynecologic cancer patients using lifelogs [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5261.

Abstract 6109: Clonal relationship of B cells between tertiary lymphoid structures (TLSs) and tumor infiltrating lymphocytes (TILs) in advanced endometrial cancer

Objective: Tertiary lymphoid structures (TLSs) are known to be a marker of peripheral inflammation. While high densities of TLSs were reported to be associated with longer patient survival in several cancer types, there is no direct evidence where B cells in TLSs(TLBs) are derived from and whether these clones are consistent with tumor infiltrating B cells (TIBs), in endometrial cancer.

Methods: We analyzed the pathological distribution of TLSs and TIBs in human endometrial cancer samples using immunohistochemistry of a series of B cell markers and evaluated the relationship with patients’ clinical outcomes. Additionally, we micro-dissected six pairs of tumor nests and their neighbor TLSs and analyzed the clonal consistency between TLBs and TIBs using the sequencing of complementarity-determining region (CDR) of B cell receptor (BCR).

Results: In 104 patients with endometrial cancer, TLSs were detected in 81 patients (78%), and the absence of TLS was related to worse progression-free survival (PFS) (HR, 0.15, P &lt;0.01). Among TLS-detected cases, the high number of TIBs was significantly associated with better PFS (P&lt;0.05). BCR analyses in the six patients found that three patients with advanced stage had a unique B cell clones in common between TLBs and TIBs, while the other three patients with early stage did not have any common B cell clones. The frequency of common B cell clones in the former three patients were 10.3% (5250/51146 reads), 9.7% (1873/19369 reads) and 3.0% (1034/34618 reads).

Conclusion: TLSs and TIBs are associated with better prognosis in endometrial cancer. Common B cell clones were found in the advanced stage cases, suggesting that B cells may have gradually acquired immunospecificity in TLSs.

Citation Format: Haruka Suzuki, Junzo Hamanishi, Meng Qin, Masayo Ukita, Akihiko Ueda, Shunsuke Kawahara, Koji Yamanoi, Taito Miyamoto, Shiro Takamatsu, Mana Taki, Yoko Hosoe, Takashi Kobayashi, Ken Yamaguchi, Masaki Mandai. Clonal relationship of B cells between tertiary lymphoid structures (TLSs) and tumor infiltrating lymphocytes (TILs) in advanced endometrial cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6109.

CXCL13-producing CD4+ T cells accumulate in early phase of tertiary lymphoid structures in ovarian cancer

Tertiary lymphoid structures (TLS) are transient ectopic lymphoid aggregates whose formation might be caused by chronic inflammation states, such as cancer. However, how TLS are induced in the tumor microenvironment (TME) and how they affect patient survival are not well understood. We investigated TLS distribution in relation to tumor infiltrating lymphocytes (TILs) and related gene expression in high-grade serous ovarian cancer (HGSC) specimens. CXCL13 gene expression correlated with TLS presence and the infiltration of T cells and B cells, and it was a favorable prognostic factor for patients with HGSC. Coexistence of CD8⁺ T cells and B cell lineages in the TME significantly improved the prognosis of HGSC and was correlated with the presence of TLS. CXCL13 expression was predominantly coincident with CD4⁺ T cells in TLS and CD8⁺ T cells in TILs, and it shifted from CD4⁺ T cells to CD21⁺ follicular DCs as TLS matured. In a mouse ovarian cancer model, recombinant CXCL13 induced TLS and enhanced survival by the infiltration of CD8⁺ T cells. These results suggest that TLS formation was associated with CXCL13-producing CD4⁺ T cells and that TLS facilitated the coordinated antitumor response of cellular and humoral immunity in ovarian cancer.

Utility of Homologous Recombination Deficiency Biomarkers Across Cancer Types

Homologous recombination DNA repair deficiency (HRD) is associated with sensitivity to platinum and poly (ADP-ribose) polymerase inhibitors in certain cancer types, including breast, ovarian, pancreatic, and prostate. In these cancers, BRCA1/2 alterations and genomic scar signatures are useful indicators for assessing HRD. However, alterations in other homologous recombination repair (HRR)-related genes and their clinical significance in other cancer types have not been adequately and systematically investigated.

A comprehensive pan-cancer analysis on the clinical significance of homologous recombination deficiency

Immunosuppressive tumor microenvironment in Uterine Serous Carcinoma via CCL7 signal with myeloid-derived suppressor cells

Serous carcinoma of the uterus (USC) is a pathological subtype of high-grade endometrial cancers, with no effective treatment for advanced cases. Since such refractory tumors frequently harbor anti-tumor immune tolerance, many immunotherapies have been investigated for various malignant tumors using immuno-competent animal models mimicking their local immunities. In this study, we established an orthotopic mouse model of high-grade endometrial cancer and evaluated the local tumor immunity to explore the efficacy of immunotherapies against USC. A multivariate analysis of 62 human USC cases revealed that the tumor infiltrating cell status, few CD8+ cells and abundant myeloid-derived suppressor cells (MDSCs), was an independent prognostic factor (p<0.005). A murine endometrial cancer cell (mECC) was obtained from C57BL/6 mice via endometrium-specific deletion of Pten and Tp53, and another high-grade cell (HPmECC) was established by further overexpressing Myc in mECCs. HPmECCs exhibited higher capacities of migration and anchorage-independent proliferation than mECCs (p<0.01, p<0.0001), and when both types of cells were inoculated into the uterus of C57BL/6 mice, the prognosis of mice bearing HPmECC-derived tumors was significantly poorer (p<0.001). Histopathological analysis of HPmECC orthotopic tumors showed serous carcinoma-like features with prominent tumor infiltration of MDSCs (p<0.05), and anti Gr-1 antibody treatment significantly prolonged the prognosis of HPmECC-derived tumor-bearing mice (p<0.05). High CCL7 expression was observed in human USC and HPmECC, and MDSCs migration was promoted in a CCL7 concentration-dependent manner. These results indicate that anti-tumor immunity is suppressed in USC due to increased number of tumor-infiltrating MDSCs via CCL signal.

B7-H3 Suppresses Antitumor Immunity via the CCL2-CCR2-M2 Macrophage Axis and Contributes to Ovarian Cancer Progression

New approaches beyond PD-1/PD-L1 inhibition are required to target the immunologically diverse tumor microenvironment (TME) in high-grade serous ovarian cancer (HGSOC). In this study, we explored the immunosuppressive effect of B7-H3 (CD276) via the CCL2-CCR2-M2 macrophage axis and its potential as a therapeutic target. Transcriptome analysis revealed that B7-H3 is highly expressed in PD-L1-low, nonimmunoreactive HGSOC tumors, and its expression negatively correlated with an IFNγ signature, which reflects the tumor immune reactivity. In syngeneic mouse models, B7-H3 (Cd276) knockout (KO) in tumor cells, but not in stromal cells, suppressed tumor progression, with a reduced number of M2 macrophages and an increased number of IFNγ⁺CD8⁺ T cells. CCL2 expression was downregulated in the B7-H3 KO tumor cell lines. Inhibition of the CCL2-CCR2 axis partly negated the effects of B7-H3 suppression on M2 macrophage migration and differentiation, and tumor progression. In patients with HGSOC, B7-H3 expression positively correlated with CCL2 expression and M2 macrophage abundance, and patients with B7-H3-high tumors had fewer tumoral IFNγ⁺CD8⁺ T cells and poorer prognosis than patients with B7-H3-low tumors. Thus, B7-H3 expression in tumor cells contributes to CCL2-CCR2-M2 macrophage axis-mediated immunosuppression and tumor progression. These findings provide new insights into the immunologic TME and could aid the development of new therapeutic approaches against the unfavorable HGSOC phenotype.

Utility of Homologous Recombination Deficiency Biomarkers Across Cancer Types

Homologous recombination DNA repair deficiency (HRD) is associated with sensitivity to platinum and poly (ADP-ribose) polymerase inhibitors in certain cancer types, including breast, ovarian, pancreatic, and prostate. In these cancers, BRCA1/2 alterations and genomic scar signatures are useful indicators for assessing HRD. However, alterations in other homologous recombination repair (HRR)-related genes and their clinical significance in other cancer types have not been adequately and systematically investigated.

METHODS

We obtained data sets of all solid tumors in The Cancer Genome Atlas and Cancer Cell Line Encyclopedia, and comprehensively analyzed HRR pathway gene alterations, their loss-of-heterozygosity status, and per-sample genomic scar scores, that is, the HRD score and mutational signature 3 ratio, DNA methylation profiles, gene expression profiles, somatic TP53 mutations, sex, and clinical or in vitro response to chemical exposure.

RESULTS

Biallelic alterations in HRR genes other than BRCA1/2 were also associated with elevated genomic scar scores. The association between HRR-related gene alterations and genomic scar scores differed significantly by sex and the presence of somatic TP53 mutations. HRD tumors determined by a combination of indices also showed HRD features in gene expression analysis and exhibited significantly higher sensitivity to DNA-damaging agents than non-HRD cases in both clinical samples and cell lines.

CONCLUSION

This study provides evidence for the usefulness of HRD analysis in all cancer types, improves chemotherapy decision making and its efficacy in clinical settings, and represents a substantial advancement in precision oncology.A comprehensive pan-cancer analysis on the clinical significance of homologous recombination deficiency.

Abstract 366: Identification of a clinically significant pan-cancer biomarker for homologous recombination deficiency

[Background] Genomic alterations in BRCA1/2 and the ‘genomic scar' signatures are associated with homologous recombination DNA repair deficiency (HRD) and serve as therapeutic biomarkers for sensitivity to platinum and PARP inhibitors in breast and ovarian cancers. However, the clinical significance of these biomarkers in other homologous recombination repair (HRR) pathway genes or in other cancer types is not fully understood.

[Method] From the TCGA and the AACR GENIE project databases, we obtained clinical and genomic data of patients with multiple solid cancers, evaluated both locus-specific LOH in HRR pathway gene mutations and two genomic scar signature scores (HRD score and mutational signature 3), identified potential HRD cases, and examined the efficacy of DNA-damaging drugs in these HRD cases.

[Results] Germline and somatic gene mutations in the HRR pathway genes with locus-specific LOH were significantly enriched in cases having high genomic scar scores, whereas those without the LOH were not enriched. Somatic mutations without the LOH were remarkably enriched in hypermutated cases and considered to be passenger mutations. The mutation rate and frequency with LOH in the HRR pathway genes varied widely by cancer type. When stratifying patients by gender and presence of TP53 mutation, the correlation between the two genomic scar scores and the resulting optimal cutoff values for biallelic HRR pathway gene alterations differed greatly. The potential HRD cases that were selected by the two genomic scar cutoffs and biallelic HRR pathway gene alterations showed significantly high gene expression-based HRD scores. In Cox proportional hazard multivariate analyses with covariates of age, stage, gender, HRD, and TP53 mutation, HRD was a good prognostic factor in the group with DNA-damaging agents, but a poor one in the group without the agents.

[Conclusion] Increased attention on locus-specific LOH in HRR pathway gene alterations and the differences in genomic scar signatures stratified by gender and TP53 mutation is newly warranted in order to properly assess HRD in a pan-cancer manner. The results in the present study proved the clinical significance of HRD across cancer types and may contribute to the development of personalized medicine based on HRD.

Citation Format: Shiro Takamatsu, JB Brown, Koji Yamanoi, Ken Yamaguchi, Junzo Hamanishi, Takashi Kobayashi, Masaki Mandai, Noriomi Matsumura. Identification of a clinically significant pan-cancer biomarker for homologous recombination deficiency [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 366.

Taxonomy and phylogeny of the Erysiphe lonicerae complex (Helotiales, Erysiphaceae) on Lonicera spp

The phylogeny and taxonomy of powdery mildews, belonging to the genus Erysiphe, on Lonicera species throughout the world are examined and discussed. Phylogenetic analyses revealed that sequences retrieved from Erysiphe lonicerae, a widespread powdery mildew species distributed in the Northern Hemisphere on a wide range of Lonicera spp., constitutes a complex of two separate species, viz., E. lonicerae (s. str.) and Erysiphe ehrenbergii comb. nov. Erysiphe lonicerae occurs on Lonicera spp. belonging to Lonicera subgen. Lonicera (= subgen. Caprifolium and subgen. Periclymenum), as well as L. japonica. Erysiphe ehrenbergii comb. nov. occurs on Lonicera spp. of Lonicera subgen. Chamaecerasus. Phylogenetic and morphological analyses have also revealed that Microsphaera caprifoliacearum (≡ Erysiphe caprifoliacearum) should be reduced to synonymy with E. lonicerae (s. str.). Additionally, Erysiphe lonicerina sp. nov. on Lonicera japonica in Japan is described and the new name Erysiphe flexibilis, based on Microsphaera lonicerae var. flexuosa, is introduced. The phylogeny of Erysiphe ehrenbergii and E. lonicerae as well as other Erysiphe species on honeysuckle is discussed, and a survey of all species, including a key to the species concerned, is provided. Citation: Bradshaw M, Braun U, Götz M, Takamatsu S (2020). Taxonomy and phylogeny of the Erysiphe lonicerae complex (Helotiales, Erysiphaceae) on Lonicera spp. Fungal Systematics and Evolution 7: 49-65. doi: 10.3114/fuse.2021.07.03.

Immunogenomic landscape of gynecologic carcinosarcoma

OBJECTIVE

Carcinosarcoma (CS) of the uterus or ovary is a rare, biphasic tumor comprising epithelial and mesenchymal elements, and exhibits more aggressive clinical features than its carcinoma counterpart. Four molecular subtypes of CS were recently established based on genomic aberration profiles (POLE, MSI, CNH, and CNL) and shown to be associated with multiple clinicopathological parameters, including patient outcomes. However, the role of the immune microenvironment in CS remains unclear. Here, we investigated the influence of the immune cells that infiltrate CS to better understand the immunological status of gynecological CS.

METHODS

Tumor immune microenvironmental analyses on CS samples were performed using immune cell profiling with RNA-seq, transcriptomic subtyping with microenvironmental genes, and T-cell receptor repertoire assay. Carcinoma and sarcoma elements from CS samples were also assessed separately.

RESULTS

Relying on estimations of tumor-infiltrating cell types from RNA-seq data, POLE and MSI (hypermutator) tumors showed an enrichment of M1 macrophages, plasma cells and CD8⁺ T cells, whereas CNH and CNL (non-hypermutator) tumors had high levels of M2 macrophages. Further subclassification by immune-related, non-cancer genes identified a fraction of tumors with distinct patient outcomes, particularly those with the CNH genomic aberration subtype. T-cell heterogeneity was independently correlated with prolonged progression-free survival. Differential analysis of carcinoma and sarcoma elements identified many shared mutations but there was little overlap in the T-cell receptor repertoire between the two elements.

CONCLUSIONS

Tumor immune microenvironmental analyses could offer potential clinical utility in the stratification of gynecological CS above classification by genomic aberration subtype alone.

Impact of radial compression protocols on the compression time and radial artery occlusion

Background

Trans-radial access (TRA) has been established as a safe and established approach for invasive coronary catheter procedures. However, protocols for post-procedural hemostasis varies depending on institutes and an evidence-based protocol is lacking.

Purpose

The objective of this study was to investigate the clinical implications of procedural hemostasis.

Methods

Consecutive patients who were referred to outpatient catheter examination before and after April 2018 were treated with an old and a new protocol, respectively. In both protocols, we used the same commercially available hemostasis band with injecting an air of 16 ml for hemostasis. In the old protocol, the amount and timing of deflation were fixed, whereas the air was removed as much as possible for every 30 minutes in the new protocol. Time to complete hemostasis, the rate of major bleeding, and the rate of radial artery occlusion (RAO) at 6 months after the catheter examination were compared between the protocols.

Results

Total of 1,843 (71±10 years old, 77% male) patients was included in the study. Between patients in the old and the new protocol group (n=1,000 and 843, respectively), there was no significant difference in age, gender, body size, or systolic blood pressure. The new group had significantly higher prevalence of diabetes (47% vs 39%, p=0.002), slightly larger sheath size (4.1±0.3 vs 4.0±0.2 Fr, p&lt;0.001), and lower rate of dual antiplatelet therapy (DAPT: 24% vs. 35%, p&lt;0.001). Time for complete hemostasis was about one-third with the new protocol compared with the old protocol (65±32 vs. 190±16 min, p&lt;0.001) and there was no major bleeding in either group. The rate of radial artery occlusion was 0.7% and 9.8% in the old and the new group (p&lt;0.001). Multivariate analysis showed that the significant predictor of prolonged hemostasis time were the old protocol (odds ratio: OR 80.5, p&lt;0.001) and the prescription of DAPT (OR 2.9, p&lt;0.001), while the factors associated with higher risk of radial occlusion were the old protocol (OR 13.9, p&lt;0.001), the number of previous TRA (OR 1.1, p&lt;0.001), and smaller body size (OR 0.127 per 1 m2 increase p=0.005).

Conclusions

Our new protocol for hemostasis after TRA was strongly associated with shorter hemostasis time and a lower rate of radial artery occlusion. This approach will decrease the post-procedural hospital time with even fewer complication rates.

Study outline

Funding Acknowledgement

Type of funding source: None

Abstract A27: Microsatellite instability and tumor mutation burden as factors in ovarian clear-cell carcinoma therapy selection

Background: Microsatellite instability (MSI) and tumor mutation burden (TMB) are being considered as predictive biomarkers for PD-1 and PD-L1 blockade immunotherapy. However, in ovarian clear-cell carcinoma (OCC), which demonstrates characteristic resistance to standard chemotherapy, the extent of MSI and TMB and their subsequent prognostic capability are unresolved. The aim of this study is to investigate TMB and MSI in OCC for improved therapy decision making.

Methods: Tumor-normal paired whole-exome data of 55 OCC patients (Itamochi et al., Br J Cancer 2017) were analyzed. Sequence data preprocessing was performed in accordance with GATK best practice workflows using BWA, Picard, the GATK toolkit, and SAMtools. Somatic SNVs and indels were detected by using Mutect and VarScan. Resulting variants were annotated by ANNOVAR, and exonic or splicing variants were extracted. SNVs with allele frequency &gt;= 2.0% were kept and further processed by the combination of the pathogenicity prediction values obtained from SIFT, PolyPhen-2, and PROVEAN; SNVs annotated as deleterious or damaging by at least one of the tools were retained. The TMB of each sample was evaluated by the total number of nonsynonymous SNVs called by the preannotation pipeline. A threshold defining high TMB was derived from the inflection point on the right tail of the TMB distribution; the resulting value was positioned at the 85th percentile of TMB values. MSI was calculated using MSIsensor, with the MSI-high classification threshold set as per the software’s documentation.

Results: Among the 55 OCC cases, 11 (20%) had at least one or a combination of either MSI-high status, mismatch repair (MMR) mutations, or TMB-high status. Specifically, three had MSI-high status, five had MMR gene mutations, and eight had TMB-high status. MSI-high samples showed elevated TMB (p= 0.052 Fisher-T). TMB was also elevated in MMR-mutated samples (p=0.018 Fisher-T). Among the three samples with MSI-high status, only one contained a deleterious mutation in MMR gene MSH6. One TMB-high sample had a POLE1 mutation. Critically, discrete- and continuous-valued survival analyses using MSI and TMB as independent variables did not suggest correlation with patient prognosis.

Conclusion: Within gynecologic oncology, MSI and TMB are correlated with prognosis in uterine endometrial cancer subtypes, though here they have demonstrated relatively reduced prognostic ability in OCC so far as examined by the samples available for this study. Thus, OCC patients are warranted the consideration of immune checkpoint inhibitor therapy at an earlier stage of treatment, and further studies to improve the resolution between MSI/TMB/MMR and phenotypical aspects should be encouraged.

Citation Format: Shiro Takamatsu, Noriomi Matsumura, J.B. Brown, Hiroaki Itamochi, Junzo Hamanishi, Ken Yamaguchi, Toru Sugiyama, Tsukasa Baba, Masaki Mandai. Microsatellite instability and tumor mutation burden as factors in ovarian clear-cell carcinoma therapy selection [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research; 2019 Sep 13-16, 2019; Atlanta, GA. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(13_Suppl):Abstract nr A27.

0922 Nightly Associations Between Pre-Bedtime Activity, Actigraphic Light, and Sleep in Children With ASD and Insomnia

Introduction

Approximately two thirds of children with Autism Spectrum Disorder (ASD) suffer from chronic insomnia. Current behavioral interventions for insomnia in children with ASD use sleep hygiene guidelines to educate parents and their children regarding sleep promoting habits. However, the relationship between pre-bedtime physical activity/light and sleep is understudied in ASD. The current study examined daily associations between pre-bedtime actigraphically assessed activity/light levels and objective/subjective sleep outcomes in children with ASD and insomnia.

Methods

Thirty children (Mage=8.5 yrs, SD=1.78 yrs) with comorbid ASD and insomnia completed 14 days of actigraphy measuring ambient white light intensity and activity levels every 30 seconds. Validated sleep scoring algorithms (in Actiware V. 6.0.9) estimated objective sleep onset latency (SOL), total sleep time (TST), wake time after sleep onset (WASO), and average activity/light levels 30, 60, and 120 mins prior to bedtime. Additionally, average activity/light levels 120-240, and 240-360 mins prior to bedtime were computed. Children also completed 14 daily sleep diaries (with parental assistance) measuring subjective reports of the same sleep parameters. Associations between daily estimations of pre-bedtime activity levels, light, and nighttime objective and subjective sleep were examined through multilevel modelling. Bonferroni corrections were performed to account for multiple comparisons.

Results

After Bonferroni corrections (p&lt;.025 significance level), greater activity within 30 minutes (B=0.0465, p=.0093) and 60 minutes (B=0.0681, p=.0005) of bedtime were associated with longer subjective SOL. Pre-bedtime light exposure was not a significant predictor of sleep outcomes.

Conclusion

Results suggest that in general, variations in daily pre-bedtime activity, but not light, are associated with worse nightly subjective SOL in children with ASD and insomnia. Findings support that sleep hygiene recommendations in children with ASD include avoidance of higher levels of pre-sleep physical activity. Prospective studies examining temporal causal relationships between pre-bedtime activity and sleep in ASD are warranted.

Support

Research was supported by a University of Missouri Research Board award (McCrae, PI; Mazurek, Co-PI). Data collected as part of clinical trial NCT02755051 Targeting Sleep in Kids with Autism Spectrum Disorder at the University of Missouri (PI: McCrae).

Malignant psoas syndrome associated with gynecological malignancy: Three case reports and a review of the literature

Malignant psoas syndrome (MPS) is a rare and unique cancer-associated syndrome caused by the malignant involvement of the psoas major muscle, and is characterized by ipsilateral lumbosacral plexopathy and painful hip flexion. The pain in MPS is often distressing and intractable, and there is no established effective treatment approach. Herein, the present study reports on three cases of MPS associated with gynecological malignancies, wherein symptom improvement was observed following chemotherapy or radiotherapy. Among 39 cases documented in the literature, female genital tract malignancies were the most frequent causes of MPS; however, the condition may be under-diagnosed, owing to the lack of general recognition. Considering the development of recent high-precision radiation therapy, palliative radiotherapy may serve an important role in the management of MPS. For physicians treating gynecological cancers, early detection of MPS is clinically important as this may allow patients to receive possible therapies and improve their quality of life in end-stage cancer. Further prospective studies should be performed to evaluate effective therapeutic approaches for MPS.

Humoral hypercalcemia caused by uterine corpus carcinosarcoma consisting of squamous cell carcinoma in its epithelial component

Humoral hypercalcemia of malignancy (HHM) is a paraneoplastic syndrome primarily caused by a tumor-producing parathyroid hormone-related protein (PTH-rP). We describe the first reported case of a uterine carcinosarcoma causing HHM. A 70-year-old patient was transferred to our hospital for a uterine tumor accompanied by impaired consciousness. The laboratory tests indicated anemia, malnutrition, elevated serum calcium and elevated PTH-rP. Emergency surgery, including abdominal hysterectomy and bilateral salpingo-oophorectomy, was performed due to uncontrollable uterine bleeding. The pathological diagnosis was carcinosarcoma consisting of pure squamous cell carcinoma in its epithelial component. Postoperatively, chemotherapy with paclitaxel and carboplatin was performed. The patient had recurrent tumors at the para-aortic lymph nodes 11 months after the initial surgery and underwent a pelvic and para-aortic lymphadenectomy, which removed all of the recurrent tumors.

Comparison of sensitivity of lung nodule detection between radiologists and technologists on low-dose CT lung cancer screening images

OBJECTIVES

The objective of this study was to compare the sensitivity of detection of lung nodules on low-dose screening CT images between radiologists and technologists.

METHODS

11 radiologists and 10 technologists read the low-dose screening CT images of 78 subjects. On images with a slice thickness of 5 mm, there were 60 lung nodules that were ≥5 mm in diameter: 26 nodules with pure ground-glass opacity (GGO), 7 nodules with mixed ground-glass opacity (GGO with a solid component) and 27 solid nodules. On images with a slice thickness of 2 mm, 69 lung nodules were ≥5 mm in diameter: 35 pure GGOs, 7 mixed GGOs and 27 solid nodules. The 21 observers read screening CT images of 5-mm slice thickness at first; then, 6 months later, they read screening CT images of 2-mm slice thickness from the 78 subjects.

RESULTS

The differences in the mean sensitivities of detection of the pure GGOs, mixed GGOs and solid nodules between radiologists and technologists were not statistically significant, except for the case of solid nodules; the p-values of the differences for pure GGOs, mixed GGOs and solid nodules on the CT images with 5-mm slice thickness were 0.095, 0.461 and 0.005, respectively, and the corresponding p-values on CT images of 2-mm slice thickness were 0.971, 0.722 and 0.0037, respectively.

CONCLUSION

Well-trained technologists may contribute to the detection of pure and mixed GGOs ≥5 mm in diameter on low-dose screening CT images.

Molecular phylogenetic analyses reveal a close evolutionary relationship between Podosphaera (Erysiphales: Erysiphaceae) and its rosaceous hosts

Podosphaera is a genus of the powdery mildew fungi belonging to the tribe Cystotheceae of the Erysiphaceae. Among the host plants of Podosphaera, 86 % of hosts of the section Podosphaera and 57 % hosts of the subsection Sphaerotheca belong to the Rosaceae. In order to reconstruct the phylogeny of Podosphaera and to determine evolutionary relationships between Podosphaera and its host plants, we used 152 ITS sequences and 69 28S rDNA sequences of Podosphaera for phylogenetic analyses. As a result, Podosphaera was divided into two large clades: clade 1, consisting of the section Podosphaera on Prunus (P. tridactyla s.l.) and subsection Magnicellulatae; and clade 2, composed of the remaining member of section Podosphaera and subsection Sphaerotheca. Because section Podosphaera takes a basal position in both clades, section Podosphaera may be ancestral in the genus Podosphaera, and the subsections Sphaerotheca and Magnicellulatae may have evolved from section Podosphaera independently. Podosphaera isolates from the respective subfamilies of Rosaceae each formed different groups in the trees, suggesting a close evolutionary relationship between Podosphaera spp. and their rosaceous hosts. However, tree topology comparison and molecular clock calibration did not support the possibility of co-speciation between Podosphaera and Rosaceae. Molecular phylogeny did not support species delimitation of P. aphanis, P. clandestina, P. ferruginea, P. spiraeae and P. tridactyla in their current circumscriptions, which suggests the need for revision of these species.

Molecular phylogeny and taxonomy of Eurasian Neoerysiphe species infecting Asteraceae and Geranium

Because Eurasian samples of Neoerysiphe collected on the Asteraceae were not identical in morphology, the molecular and morphological differences among these specimens were compared with those of the American N. cumminsiana. Neoerysiphe on Asteraceae was found to consist of at least four different species. Three of them are described as new species, viz. N. hiratae, N. joerstadii, and N. nevoi. Neoerysiphe hiratae is a Japanese species parasitizing hosts belonging to the genera Cacalia and Ligularia (tribe Senecioneae). Neoerysiphe joerstadii was found in Israel on Phagnalon rupestre (tribe Gnaphalieae). Neoerysiphe nevoi was recorded in Israel and Ukraine on a number of hosts in different genera but all belonging to tribe Cichorieae. Thus, Eurasian Neoerysiphe species infecting the Asteraceae are strongly specialised to particular tribes of this family. Phylogenetic analyses indicated that the three new species were not closely allied. Neoerysiphe hiratae is related to the American N. cumminsiana and species belonging to Oidium subg. Striatoidium. Neoerysiphe nevoi is sister to N. geranii, and N. joerstadii is allied to N. galii. In addition, Ukrainian Neoerysiphe samples on Geranium were phylogenetically and morphologically identical to Japanese samples of N. geranii, and this fungus seems to be an invasive species in Ukraine.

Rapid and accurate identification of microorganisms contaminating cosmetic products based on DNA sequence homology

The aim of this study was to develop rapid and accurate procedures to identify microorganisms contaminating cosmetic products, based on the identity of the nucleotide sequences of the internal transcribed spacer (ITS) region of the ribosomal RNA coding DNA (rDNA). Five types of microorganisms were isolated from the inner portion of lotion bottle caps, skin care lotions, and cleansing gels. The rDNA ITS region of microorganisms was amplified through the use of colony-direct PCR or ordinal PCR using DNA extracts as templates. The nucleotide sequences of the amplified DNA were determined and subjected to homology search of a publicly available DNA database. Thereby, we obtained DNA sequences possessing high similarity with the query sequences from the databases of all the five organisms analyzed. The traditional identification procedure requires expert skills, and a time period of approximately 1 month to identify the microorganisms. On the contrary, 3-7 days were sufficient to complete all the procedures employed in the current method, including isolation and cultivation of organisms, DNA sequencing, and the database homology search. Moreover, it was possible to develop the skills necessary to perform the molecular techniques required for the identification procedures within 1 week. Consequently, the current method is useful for rapid and accurate identification of microorganisms, contaminating cosmetics.

Neuroprotective effect of chronic lithium treatment against hypoxia in specific brain regions with upregulation of cAMP response element binding protein and brain-derived neurotrophic factor but not nerve growth factor: comparison with acute lithium treatment

OBJECTIVES

We evaluated the neuroprotective effect of chronically or acutely administered lithium against hypoxia in several brain regions. Furthermore, we investigated the contribution of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), and cAMP response element binding protein (CREB) to the neuroprotective effect of lithium.

METHODS

Brain slices were prepared from rats that had been treated chronically or acutely with lithium. The cerebral glucose metabolic rate (CMRglc) before and after hypoxia loading to brain slices was measured using the dynamic positron autoradiography technique with [(18)F]2-fluoro-2-deoxy-D-glucose. The changes of expression of proteins were investigated using Western blot analysis.

RESULTS

Before hypoxia loading, the CMRglc did not differ between the lithium-treated and untreated groups. After hypoxia loading, the CMRglc of the untreated group was significantly lower than that before hypoxia loading. However, the CMRglc of the chronic lithium treatment group recovered in the frontal cortex, caudate putamen, hippocampus and cerebellum, but not in the thalamus. In contrast, the CMRglc of the acute lithium treatment group did not recover in any analyzed brain regions. After chronic lithium treatment, the levels of expression of BDNF and phospho-CREB were higher than those of untreated rats in the frontal cortex, but not in the thalamus. However, the expression of NGF did not change in the frontal cortex and thalamus.

CONCLUSIONS

These results demonstrated that lithium was neuroprotective against hypoxia only after chronic treatment and only in specific brain regions, and that CREB and BDNF might contribute to this effect.

Region-specific induction of hypoxic tolerance by expression of stress proteins and antioxidant enzymes

We examined the induction of hypoxic tolerance after hypoxic preconditioning in the frontal cortex, caudate putamen and thalamus using the dynamic positron autoradiography technique and [18F]2-fluoro-2-deoxy-D-glucose with rat brain slices. Hypoxic tolerance induction was confirmed in the frontal cortex, but not in the caudate putamen and thalamus. Next, we compared the gene expression in the frontal cortex and caudate putamen using the ATLAS Rat Stress Array, and found that the expression of 150-kDa oxygen-regulated protein and mitochondrial heat shock protein 70 as stress proteins, and copper-zinc-containing superoxide dismutase and manganese-containing superoxide dismutase as antioxidant enzymes was elevated only in the frontal cortex. These results suggest that the induction of hypoxic tolerance after hypoxic preconditioning is region-specific, and stress proteins and antioxidant enzymes participate in this phenomenon.

Microbial community change of sulfate reduction and sulfur oxidation bacteria in the activated sludge cultivated with acetate and peptone

The growth of sulfate reducing bacteria (SRB) and filamentous sulfur bacteria was monitored on a laboratory scale in activated sludge reactors using acetate and peptone as the artificial wastewater. When the artificial wastewater contained acetate and peptone, filamentous bacteria increased in the sludge and the SVI values increased. There was a good correlation between sulfate reducing activity and sulfur oxidation activity in the produced sludge. The microbial community change of filamentous sulfur bacteria and sulfate reducing bacteria was analyzed using the fluorescent in situ hybridization (FISH) method. The tendency for the growth of filamentous sulfur bacteria Thiothrix eikelboomii following the growth of SRB was observed. The percentage of SRB385- hybridized cells and DNMA657-hybridized cells found in the total cell area increased from 2-3% to 7-10% when the filamentous bulking occurred.

Intraluminal duodenal diverticulum: MR findings

We report a case of intraluminal duodenal diverticulum with special reference to its magnetic resonance imaging findings. An intraluminal duodenal fluid collection surrounded by a hypointense rim on T2-weighted or magnetic resonance cholangiopancreatographic images, the shape of which is changed by peristalsis, is considered to be almost diagnostic for intraluminal duodenal diverticulum.

Solid serous cystadenoma of the pancreas: MR imaging with pathologic correlation

We report a case of solid type serous cystadenoma of the pancreas. Computed tomographic and magnetic resonance (MR) images showed a hypervascular solid tumor that was difficult to differentiate from endocrine tumor of the pancreas. However, the tumor showed marked hyperintensity similar to that of hepatic cyst on MR cholangiopancreatography, indicating not a solid but rather a cystic nature. MR cholangiopancreatography (heavily T2-weighted image) is quite useful for clearly differentiating solid from cystic tumors.

Treatment strategy for Boerhaave's syndrome

Esophageal rupture is a potentially mortal condition. Rapid and correct diagnosis, and urgent surgical treatment with esophagectomy is indicated, but conservative and other surgical treatments have also been reported recently. The treatment strategies for esophageal rupture are discussed here, based on our experiences with four cases during the last 10 years. They were admitted urgently and each was treated by a different method. Three of them underwent emergency operations, one undergoing primary closure of the ruptured esophagus, another received a T-tube insertion from the ruptured site with omental flap, and the third an esophagogastrectomy. The fourth case was treated conservatively. All patients survived and were discharged 36-144 days post treatment. One of them was readmitted for debridement of necrotic rib. In conclusion, the prompt and accurate diagnosis of esophageal rupture is crucial for a subsequent successful treatment. Conservative treatment or operation including esophagectomy will be determined by the severity of the condition.

Introduction of a benzoyl group onto 6-chloropurine riboside in aqueous solution and its application to the synthesis of nucleoside derivatives

A benzoyl group was introduced onto the 3'-hydroxyl group of 6-chloropurine riboside by treatment with benzoic anhydride in the presence of a base in aqueous solution. The product (3b) was converted to 9-(2,3-Di-deoxy-2-fluoro-beta-D-threo-pentofuranosyl)adenine (1, FddA) in 6 steps, including radical deoxygenation.