The Japanese Breast Cancer Society Clinical Practice Guidelines for systemic treatment of breast cancer, 2022 edition

The Japanese Breast Cancer Society (JBCS) Clinical Practice Guidelines for systemic treatment of breast cancer were updated to the 2022 edition through a process started in 2018. The updated guidelines consist of 12 background questions (BQs), 33 clinical questions (CQs), and 20 future research questions (FRQs). Multiple outcomes including efficacy and safety were selected in each CQ, and then quantitative and qualitative systematic reviews were conducted to determine the strength of evidence and strength of recommendation, which was finally determined through a voting process among designated committee members. Here, we describe eight selected CQs as important updates from the previous guidelines, including novel practice-changing updates, and recommendations based on evidence that has emerged specifically from Japanese clinical trials.

Neurofibroma with adenosis in the mammary gland: a case report

BACKGROUND

Neurofibroma of the breast is extremely rare, with only a few reported cases. Here, we report a case of solitary neurofibroma of the breast in a 95-year-old woman.

CASE PRESENTATION

A 95-year-old woman presented with a palpable mass in the left breast. Mammography revealed a well-defined mass. A 1.6-cm round mass was found in the lower outer quadrant of the left breast on ultrasonography. The internal echo of the tumor was a mixture of relatively uniform hypoechoic areas with posterior enhancement and heterogeneous hyperechoic areas. She underwent a core needle biopsy. The pathological findings revealed a spindle cell lesion with no malignant findings. At 2 months follow-up, repeat breast ultrasonography showed that the mass had enlarged to be 2.7 cm in size. A repeat core needle biopsy, however, revealed no particularly new information. Because the tumor was growing and a definite diagnosis was not made, lumpectomy was performed. We found bland-spindled cells with shredded-carrot collagen bundles. Immunohistochemical antibody markers (S100, SOX10, and CD34) were positive for the spindle cells. Some of the tumors maintained the bilayer nature of luminal cells and myoepithelial cells, which might be the reason for internal heterogeneity on ultrasound. A histological diagnosis of neurofibroma with adenosis was made. At 6 months follow-up, no recurrent lesions were found.

CONCLUSIONS

Ultrasound and pathological images revealed an extremely rare case of neurofibroma combined with adenosis. Tumor resection was performed because it was difficult to make a definitive diagnosis using needle biopsy. Even when a benign tumor is suspected, short-term follow-up is necessary, and if an enlargement is observed, early tumor resection is recommended.

Lipidomics-based tissue heterogeneity in specimens of luminal breast cancer revealed by clustering analysis of mass spectrometry imaging: A preliminary study

Cancer tissues reflect a greater number of pathological characteristics of cancer compared to cancer cells, so the evaluation of cancer tissues can be effective in determining cancer treatment strategies. Mass spectrometry imaging (MSI) can evaluate cancer tissues and even identify molecules while preserving spatial information. Cluster analysis of cancer tissues' MSI data is currently used to evaluate the phenotype heterogeneity of the tissues. Interestingly, it has been reported that phenotype heterogeneity does not always coincide with genotype heterogeneity in HER2-positive breast cancer. We thus investigated the phenotype heterogeneity of luminal breast cancer, which is generally known to have few gene mutations. As a result, we identified phenotype heterogeneity based on lipidomics in luminal breast cancer tissues. Clusters were composed of phosphatidylcholine (PC), triglycerides (TG), phosphatidylethanolamine, sphingomyelin, and ceramide. It was found that mainly the proportion of PC and TG correlated with the proportion of cancer and stroma on HE images. Furthermore, the number of carbons in these lipid class varied from cluster to cluster. This was consistent with the fact that enzymes that synthesize long-chain fatty acids are increased through cancer metabolism. It was then thought that clusters containing PCs with high carbon counts might reflect high malignancy. These results indicate that lipidomics-based phenotype heterogeneity could potentially be used to classify cancer for which genetic analysis alone is insufficient for classification.

Ubiquitin-like 3 as a new protein-sorting factor for small extracellular vesicles

Ubiquitin-like 3 (UBL3) is a well-conserved ubiquitin-like protein (UBL) in eukaryotes and regulates the ubiquitin cascade, but the significant roles of UBL3 in cellular processes remained unknown. Recently, UBL3 was elucidated to be a post-translational modification factor that promotes protein sorting to small extracellular vesicles (sEVs). Proteins sorted into sEVs have been studied as etiologies of sEV-related diseases. Also, there have been attempts to construct drug delivery systems (DDSs) by loading proteins into sEVs. In this review, we introduce the new concept that UBL3 has a critical role in the protein-sorting system and compare structure conservation between UBL3 and other UBLs from an evolutionary perspective. We conclude with future perspectives for the utility of UBL3 in sEV-related diseases and DDS.Key words: UBL3, small extracellular vesicles, protein sorting, ubiquitin-like protein, post-translational modification.

Correction to: The Japanese Breast Cancer Society Clinical Practice Guidelines for systemic treatment of breast cancer, 2018 edition

A correction to this paper has been published: https://doi.org/10.1007/s12282-021-01252-x

A difficult-to-diagnose fibromatosis-like metaplastic carcinoma of the breast: a case report

Background

Fibromatosis-like metaplastic carcinoma (FLMCa), classified as a metaplastic carcinoma of the breast, is a very rare type of metaplastic carcinoma. We report a case of FLMCa that was difficult to diagnose.

Case presentation

The patient was a 56-year-old postmenopausal woman who presented with a left-sided breast mass. A 1.3-cm irregular mass was found in the lower outer quadrant of the left breast on breast ultrasonography. She underwent core needle biopsy and vacuum-assisted biopsy, but the pathological findings only revealed inflammatory cell infiltration and a high level of fibrosis, with no malignant findings. At 3 months follow-up, she underwent a repeat breast ultrasonography, which revealed an increase in the size of the mass to 1.8 cm, and a repeat core needle biopsy, which showed a few spindle cells and squamous cells positive for cytokeratin (CK)5/6 and AE1/AE3, leading to the suspicion of FLMCa. Since the amount of tissue was insufficient to establish a definitive diagnosis, she underwent a lumpectomy. We found low-grade and slightly atypical spindle cells and partly atypical spindle cell carcinoma and squamous cell carcinoma. CK5/6 and α-SMA were positive, thus confirming FLMCa. Because the margins on the edge of the nipple side and anterior side were “ink on tumor”, she underwent a mastectomy and sentinel lymph node biopsy. After the surgery, she received adjuvant chemotherapy. At 3 years and 8 months of follow-up, no recurrent or metastatic lesions were identified in her body.

Conclusions

FLMCa should be considered in the differential diagnosis when collagenous fibers are proliferating and malignancy is clinically suspected. Immunohistochemical analysis may be helpful in confirming this diagnosis.

Comparison of survival and perioperative outcome of the colonic stent and the transanal decompression tube placement and emergency surgery for left-sided obstructive colorectal cancer: a retrospective multi-center observational study "The CODOMO study"

PURPOSE

Advances in endoscopic technology have led to the reevaluation of self-expandable metallic stent (SEMS) placement as a bridge-to-surgery (BTS) in patients with obstructive colorectal cancer. In Japan, after inclusion of SEMS placement as a BTS in the medical insurance coverage in 2012, this procedure has been increasingly performed. However, a transanal decompression tube (TADT) placement has been used as a BTS. We aimed to retrospectively evaluate the optimal strategy for obstructive left-sided colorectal cancer (OLCRC) by comparing SEMS and TADT placement with emergency surgery.

METHODS

We included 301 patients with stage II and III OLCRC from 27 institutions. The study patients were divided into Surgery group (emergency surgery, n = 103), SEMS group (BTS by SEMS, n = 113), and TADT group (BTS by TADT, n = 85). We compared the survival and perioperative outcomes of patients in the Surgery group as a standard treatment with those in the SEMS and TADT groups.

RESULTS

The 3-year relapse-free survival rate in patients in the Surgery group was 74.8%, while that in patients in the SEMS group and TADT group were 69.0% (p = 0.39) and 55.3% (p = 0.006), respectively. The technical success rate was not statistically different, but the clinical success rate was significantly higher in the SEMS group than in the TADT group (p = 0.0040). With regard to postoperative complications after curative surgery, the SEMS group had significantly lower of complications (≥ grade 2) than the Surgery group (p = 0.022).

CONCLUSION

Patients who underwent SEMS placement for OLCRC had similar oncological outcomes to patients who underwent emergency surgery.

Trastuzumab, pertuzumab, and eribulin mesylate versus trastuzumab, pertuzumab, and a taxane as a first-line or second-line treatment for HER2-positive, locally advanced or metastatic breast cancer: study protocol for a randomized controlled, non-inferiority, phase III trial in Japan (JBCRG-M06/EMERALD)

Background

Trastuzumab (Tmab), pertuzumab (Pmab), and taxane has been a standard first-line treatment for recurrent or metastatic human epidermal growth factor (HER2)-positive breast cancer (HER2⁺ mBC) but has some safety issues due to taxane-induced toxicities. This has led to ongoing efforts to seek less toxic alternatives to taxanes that are equally effective when used in combination with Tmab plus Pmab. This study aims to show the non-inferiority of eribulin, a non-taxane microtubule inhibitor, against taxane, as a partner for dual HER2 blockade.

Methods/design

This multicenter, randomized, open-label, parallel-group, phase III study will involve a total of 480 Japanese women with HER2⁺ mBC who meet the following requirements: (1) age 20–70 years; (2) no prior cytotoxic chemotherapy (excluding trastuzumab-emtansine) for mBC; (3) ≥ 6 months after prior neoadjuvant or adjuvant cytotoxic chemotherapy; (4) presence of any radiologically evaluable lesion; (5) left ventricular ejection fraction ≥ 50%; (6) Eastern Cooperative Oncology Group performance status score of 0 or 1; (7) adequate organ function; and (8) life expectancy of at least 6 months. They will be randomized 1:1 to receive eribulin (1.4 mg/m² on days 1 and 8) or taxane (docetaxel 75 mg/m² on day 1 or paclitaxel 80 mg/m² on days 1, 8, and 15) in combination with Tmab (8 mg/kg then 6 mg/kg) plus Pmab (840 mg then 420 mg) on day 1 of each 21-day cycle. The treatment will be continued until disease progression or unmanageable toxicity. The primary endpoint is progression-free survival as per investigator according to RECIST v1.1 criteria. Key secondary endpoints include objective response rate, overall survival, quality of life and safety. Non-inferiority will be tested with two margins of 1.33 and 1.25 in a stepwise manner. If non-inferiority is shown with a margin of 1.25, superiority will then be tested.

Discussion

If this study shows the non-inferiority, or even superiority, of Tmab, Pmab, and eribulin against the existing taxane-containing regimen, this new regimen may become a standard first- or second-line treatment option for HER2⁺ mBC in Japan.

Trial registration

ClinicalTrials.gov, ID: NCT03264547. Registered on 28 June 2017.

The Japanese Breast Cancer Society Clinical Practice Guidelines for systemic treatment of breast cancer, 2018 edition

Purpose

We present the English version of The Japanese Breast Cancer Society (JBCS) Clinical Practice Guidelines for systemic treatment of breast cancer, 2018 edition.

Methods

The JBCS formed a task force to update the JBCS Clinical Practice Guidelines, 2015 edition, according to Minds Handbook for Clinical Practice Guideline Development 2014. First, we set multiple outcomes for each clinical question (CQ). Next, quantitative or qualitative systematic review was conducted for each of the multiple outcomes, and the strength of recommendation for the CQ was taken into consideration during meetings, with the aim of finding a balance between benefit and harm. Finalized recommendations from each session were confirmed through discussion and voting at the recommendation decision meeting.

Results

The recommendations, the strength of recommendation and the strength of evidence were determined based on systemic literature reviews and the meta-analyses for each CQ.

Conclusion

The JBCS updated the Clinical Practice Guidelines for systemic treatment of breast cancer.

Electronic supplementary material

The online version of this article (10.1007/s12282-020-01085-0) contains supplementary material, which is available to authorized users.

Preoperative concurrent endocrine therapy with chemotherapy in luminal B-like breast cancer

PURPOSE

Luminal B-like breast cancer is sensitive to both chemotherapy and endocrine therapy. We aimed to assess the safety and efficacy of concomitant chemotherapy and endocrine therapy compared with chemotherapy alone in the preoperative setting in luminal B-like breast cancer.

METHODS

This two-arm randomized clinical trial enrolled patients with luminal B-like human epithelial growth factor 2-negative breast cancer, who were randomly assigned at a 1:1 ratio to receive preoperative chemotherapy alone or preoperative endocrine therapy concurrent with chemotherapy for 24 weeks before surgery. The primary endpoint was the pathological complete response (pCR) rate. The secondary endpoints included the clinical response rate, toxicity, and health-related quality of life (HRQOL).

RESULTS

Overall, 70 patients were randomly assigned to the chemotherapy and chemo-endocrine therapy groups. The pCR rates were 9.7% and 3.0% (P = 0.319), and the clinical complete response rates were 5.9% and 5.6% (P = 0.745) in the chemotherapy and chemo-endocrine therapy groups, respectively. There were no clear differences in treatment-related adverse events or HRQOL between the two groups.

CONCLUSIONS

In patients with luminal B-like breast cancer, the pCR, clinical response rate, toxicity, and HRQOL with the concomitant administration of endocrine therapy and chemotherapy were not superior to chemotherapy alone in the preoperative setting.

Abstract P5-13-03: An efficacy and safety trial of preoperative chemo-endocrine therapy in Luminal B-like (HER2-negative) breast cancer

Background: The St.Gallen consensus guideline recommends the sequential administration chemotherapy followed by endocrine therapy as postoperative therapy for the higher risk of ER-positive breast cancer patients based on results of a single study. In metastatic settings, however, several trials conducted in the 1980s' demonstrated that tumor response rates were higher when chemotherapy and tamoxifen was concomitantly administered than when chemotherapy and tamoxifen administered were given sequentially. In the preoperative settings, pathological complete response (pCR) rate can be used as a surrogate marker to predict event-free survival or overall survival in Luminal B-like (HER2-negative) breast cancer. We, therefore, designed a prospective randomized safety and efficacy trial in order to test a hypothesis that the concomitant administration of an aromatase inhibitor and chemotherapy improves pathological complete response (pCR) rate than chemotherapy alone in the preoperative setting. Trial design: This two-arm randomized clinical trial enrolled operable breast cancer patients with Luminal B-like (HER2-negative) subtype. Patients were randomly assigned (1:1) to receive preoperative chemotherapy alone or preoperative chemotherapy concurrent with endocrine therapy for 24 weeks before surgery. Chemotherapy consisted of 12 cycles of weekly paclitaxel followed by 4 cycles of every 3-week AC. Endocrine therapy consisted of anastrozole for postmenopausal patients or anastrozole plus leuprorelin for premenopausal patients. Eligibility criteria: 1)Female patients with operable and histologically confirmed invasive breast cancer; 2)HER2-negative; 3)Either ER-positive or PgR-positive; 4)Either Ki67-LI>=14% and NG>=2 or NG=3 regardless of Ki67-LI. Endpoints: Primary endpoint is the pCR rate. Secondary endpoints are the clinical response rate (RECIST), the breast-conserving surgery rate, the adverse events, and HRQOL. Results: Between March 2012 and August 2017, 70 patients were randomly assigned to chemotherapy group (n=34) or chemo-endocrine therapy group (n=36). pCR rates were 8.8 % and 2.7 % in the chemotherapy and the chemo-endocrine group, respectively (P = 0.319). Similarly, clinical complete response rates were 5.9 % and 5.6 % in the chemotherapy and the chemo-endocrine group, respectively (P = 0.745). There were no clear differences in treatment-related side effects and HRQOL between interventions. Conclusion: The concomitant administration of endocrine therapy and chemotherapy in Luminal B-like breast cancer patients is similar to chemotherapy alone in pCR rate and clinical response in the preoperative setting.

Citation Format: Roichi Matsunuma, Toru Watanabe, Yasuo Hozumi, Kei Koizumi, Yasushi Ito, Hirofumi Fujita, Hiroyuki Ogura, Keigo Goto, Hiroki Mori, Noriko Sawai, Norihiko Shiiya. An efficacy and safety trial of preoperative chemo-endocrine therapy in Luminal B-like (HER2-negative) breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-13-03.

Efficacy of denosumab for restoring normal bone mineral density in women receiving adjuvant aromatase inhibitors for early breast cancer

BACKGROUND

Osteoporosis is a major side effect of aromatase inhibitors (AIs), which are greatly effective in the treatment of breast cancer. However, there are no satisfactory measures against osteoporosis. In this multicenter, randomized, comparative study, we evaluate the efficacy of denosumab for preventing loss of bone mineral density (BMD) induced by adjuvant therapy with AI s in breast cancer patients with normal BMD.

PATIENTS AND METHODS

The bone loss-suppressing effect of denosumab will be comparatively evaluated in postmenopausal patients scheduled to receive letrozole or anastrozole as a postoperative endocrine therapy for stage I-IIIA hormone-sensitive breast cancer and a control group. Patients will be administered letrozole 2.5 mg or anastrozole 1 mg once a day, and the treatment will be continued for 5 years unless recurrence, secondary cancer, or unacceptable toxicity develops. Patients in the denosumab group will receive a subcutaneous injection of 60 mg of denosumab every 6 months. The primary endpoint is the rate of change in the lumbar spine (L1-L4) BMD, as determined by dual-energy X-ray absorptiometry (DXA), 12 months after the start of the injection. The secondary endpoints were ETHICS AND DISSEMINATION:: The protocol was approved by the institutional review boards of Kyoto Prefectural University of Medicine and all the participating faculties. Written informed consent was obtained from all patients before registration, in accordance with the Declaration of Helsinki. Results of the study will be disseminated via publications in peer-reviewed journals.

TRIAL REGISTRATION

Clinical Trials.gov Identifier: NCT03324932, Japan Registry of Clinical Trial (jRCT): CRB5180001.

Abstract OT2-07-05: A phase III trial to compare eribulin mesylate + trastuzumab (H) + pertuzumab (P) with paclitaxel or docetaxel + HP for HER2-positive advanced or metastatic breast cancer (JBCRG-M06/ EMERALD)

Background: Docetaxel + Trastuzumab (H) + Pertuzumab (P) provided progression-free survival (PFS) and overall survival (OS) benefits in HER2-positive advanced or metastatic breast cancer (AMBC) in the CLEOPATRA study as a first-line therapy. However, long-term administration of docetaxel at a dose of 75 mg/m2 every 3 weeks in AMBC patients (pts) is difficult due to the toxicities. Eribulin mesylate (E) is a well-tolerated microtubule inhibitor, and we have reported the efficacy and safety of EHP regimen as first- and second-line therapy for AMBC in a multicenter, phase II study (JBCRG-M03/UMIN000012232). In this M06 study, we address the clinical question as to which is the better chemotherapy partner for HP as first line regimen, in terms of efficacy, toxicity and QOL.

Methods: JBCRG-M06 is a multicenter open-label randomized phase III study for HER2-positive AMBC pts who have received no prior chemotherapy except for the HER2- Antibody-Drug Conjugate (ADC). Pts will be randomized 1:1 to E (1.4mg/m2 on day 1 and 8) + H (8 mg/kg loading dose followed by 6 mg/kg) +P (840 mg loading dose followed by 420 mg) q3wks or standard taxanes (docetaxel 75mg/m2 on day1 or paclitaxel 80mg/m2 on day 1, 8 and 15) + HP q3wks. Stratification factors for randomization are; presence of visceral metastases, number of prior taxanes on perioperative adjuvant treatment, and treatment with prior anti-HER2-ADC. Primary endpoint is PFS and secondary endpoints include overall response rate, duration of response, OS, patient-reported outcomes (PRO) relating to QOL and peripheral neuropathy, new-metastases free survival, and safety. Translational research to search for biomarker for individual precision therapy will be performed. Main eligibility criteria are as follows: pts with HER2-positive AMBC, female aged 20-70 years old, ECOG PS of 0-1, LVEF ≥ 50% at baseline and adequate organ function. Pts who had progressive MBC within 6 months after the end of primary adjuvant systemic chemotherapy are excluded. The sample size was calculated by type1 error (2-sided) of 0.05 and 80% power to estimate the noninferiority margin 1.33 with an expected median PFS of 14.2 months. The target number of pts is 480 recruited over the duration of 3-years. The first patient in was achieved on August 2017. (ClinicalTrials.gov Identifier:NCT03264547).

Citation Format: Masuda N, Yamashita T, Saji S, Araki K, Ito Y, Takano T, Takahashi M, Tsurutani J, Koizumi K, Kitada M, Kojima Y, Sagara Y, Tada H, Iwasa T, Kadoya T, Iwatani T, Hasegawa H, Morita S, Ohno S. A phase III trial to compare eribulin mesylate + trastuzumab (H) + pertuzumab (P) with paclitaxel or docetaxel + HP for HER2-positive advanced or metastatic breast cancer (JBCRG-M06/ EMERALD) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-07-05.

Oxygen ultra-fine bubbles water administration prevents bone loss of glucocorticoid-induced osteoporosis in mice by suppressing osteoclast differentiation

Oxygen ultra-fine bubbles (OUB) saline injection prevents bone loss of glucocorti\coid-induced osteoporosis in mice, and OUB inhibit osteoclastogenesis via RANK-TRAF6-c-Fos-NFATc1 signaling and RANK-p38 MAPK signaling in vitro.

INTRODUCTION

Ultra-fine bubbles (<200 nm in diameter) have several unique properties, and they are tested in various medical fields. The purpose of this study was to investigate the effects of oxygen ultra-fine bubbles (OUB) on glucocorticoid-induced osteoporosis (GIO) model mice.

METHODS

Prednisolone (PSL, 5 mg) was subcutaneously inserted in 6-month-old male C57BL/6J mice, and 200 μl of saline, OUB-diluted saline, or nitrogen ultra-fine bubbles (NUB)-diluted saline was intraperitoneally injected three times per week for 8 weeks the day after operations. Mice were divided into four groups; (1) control, sham-operation + saline; (2) GIO, PSL + saline; (3) GIO + OUB, PSL + OUB saline; (4) GIO + NUB, PSL + NUB saline. The effects of OUB on osteoblasts and osteoclasts were examined by serially diluted OUB medium in vitro.

RESULTS

Bone mass was significantly decreased in GIO [bone volume/total volume (%): control vs. GIO 12.6 vs. 7.9; p < 0.01] while significantly preserved in GIO + OUB (GIO vs. GIO + OUB 7.9 vs. 12.9; p < 0.05). In addition, tartrate-resistant acid phosphatase (TRAP)-positive cells in the distal femur [mean osteoclasts number/bone surface (mm^-1)] was significantly increased in GIO (control vs. GIO 6.8 vs. 11.6; p < 0.01) while suppressed in GIO + OUB (GIO vs. GIO + OUB 11.6 vs. 7.5; p < 0.01). NUB did not affect these parameters. In vitro experiments revealed that OUB significantly inhibited osteoclastogenesis by inhibiting RANK-TRAF6-c-Fos-NFATc1 signaling, RANK-p38 MAPK signaling, and TRAP/Cathepsin K/DC-STAMP mRNA expression in a concentration-dependent manner. OUB did not affect osteoblastogenesis in vitro.

CONCLUSIONS

OUB prevent bone loss in GIO mice by inhibiting osteoclastogenesis.

Synovial mesenchymal stem cells from osteo- or rheumatoid arthritis joints exhibit good potential for cartilage repair using a scaffold-free tissue engineering approach

OBJECTIVE

To assess whether synovial mesenchymal stem cells (SMSCs) from patients with osteoarthritis (OA) or rheumatoid arthritis (RA) can be used as an alternative cell source for cartilage repair using allogenic tissue engineered construct (TEC).

METHODS

Twenty-five patients (17 female, average age 61.8 years) were divided according to their pathology (control trauma group; N = 6, OA group; N = 6) and RA patients were subdivided into two groups to evaluate the impact of biologics in accordance with whether treated with biologics [Bio(+)RA; N = 7] or not [Bio(-)RA; N = 6]. We compared the following characteristics among these groups: (1) The cell proliferation capacity of SMSCs; (2) The influence of passage number on features of SMSCs; (3) The weight and volume of TEC from the same number of SMSCs; (4) Inflammatory cytokine gene expressions levels of TEC; (5) The chondrogenic potential of TEC; and (6) Osteochondral repair using TEC in athymic nude rats.

RESULTS

SMSCs from the four groups exhibited equivalent features in the above evaluation items. In in vivo studies, the TEC-treated repair tissues for all groups exhibited significantly better outcomes than those for the untreated group and no significant differences among the four TEC groups.

CONCLUSION

SMSCs from OA or RA patients are no less appropriate for repairing cartilage than those from trauma patients and thus, may be an effective source for allogenic cell-based cartilage repair.

Gli2 protein expression level is a feasible marker of ligand-dependent hedgehog activation in pancreatic neoplasms

The hedgehog pathway is known to promote proliferation of pancreatic ductal adenocarcinoma (PDA) and has been shown to restrain tumor progression. To understand how hedgehog causes these effects, we sought to carefully examine protein expression of hedgehog signaling components during different tumor stages. Genetically engineered mice, Pdx1-Cre;LSL-KrasG12D and Pdx1-Cre;LSL-KrasG12D;p53lox/+, were utilized to model distinct phases of tumorigenesis, pancreatic intraepithelial neoplasm (PanIN) and PDA. Human pancreatic specimens of intraductal papillary mucinous neoplasm (IPMN) and PDA were also employed. PanIN and IPMN lesions highly express Sonic Hedgehog, at a level that is slightly higher than that observed in PDA. GLI2 protein is also expressed in both PanIN/IPMN and PDA. Although there was no difference in the nuclear staining, the cytoplasmic GLI2 level in PDA was modest in comparison to that in PanIN/IPMN. Hedgehog interacting protein was strongly expressed in the precursors, whereas the level in PDA was significantly attenuated. There were no differences in expression of Patched1 at early and late stages. Finally, a strong correlation between Sonic Hedgehog and GLI2 staining was found in both human and murine pancreatic tumors. The results indicate that the GLI2 protein level could serve as a feasible marker of ligand-dependent hedgehog activation in pancreatic neoplasms.

Comparison of the prognosis of bisphosphonate-related osteonecrosis of the jaw caused by oral and intravenous bisphosphonates

Bisphosphonates (BPs) have been used in medical practice for the treatment of osteoporosis, bone metastasis, and multiple myeloma. Although many studies have been published, the treatment and prognosis of bisphosphonate-related osteonecrosis of the jaw (BRONJ) remain unclear. This study included 59 patients with BRONJ: 29 had taken oral BPs and 30 had taken intravenous (IV) BPs. All received conservative treatments. When separated sequestra were seen, a sequestrectomy was performed. Segmental mandibular resection was performed when pathological fractures were diagnosed. The outcomes of treatments were compared between groups. For patients treated with oral rinses or mandibular resection, the number in whom clinical healing was observed did not differ between the oral BP and IV BP groups. With regard to sequestrectomy, 94% of patients in the oral BP group showed improvement with this treatment compared to 50% in the IV BP group. The number of patients in whom clinical healing of BRONJ was achieved was statistically better in the oral BP group than in the IV BP group after 6 months of treatment (P<0.001). The results showed that >90% of patients treated with oral BPs could be cured. However, 50% of patients treated with IV BPs did not show an improvement. Additional research is needed to further increase the therapeutic efficacy for the resolution of BRONJ.

Galactosylation at Side Chains of Branched Cyclodextrins by Various β-Galactosidases

The galactosyl transfer reaction to branched cyclodextrins (CDs) was investigated using lactose as a donor substrate and branched CDs as acceptors by various beta-galactosidases. Bacillus circulans beta-galactosidase synthesized galactosyl transfer products to branched CDs, of which the galactose residues were linked at side chains of branched CDs, not directly at CD rings. Aspergillus oryzae and Penicillium multicolor beta-galactosidases also produced derivatives galactosylated at side chains of branched CDs. The structures of main transgalactosylation products of branched CDs by these beta-galactosidases seem to be different from those by B. circulans beta-galactosidase, judging from the retention times on high performance liquid chromatography.

Acceptor Specificity of Cyclodextrin Glycosyltransferase fromBacillus stearothermophilusand Synthesis of α-D-GlucosylO-β-D-galactosyl-(1→4)-β-D-glucoside

Bacillus stearothermophilus CGTase had a wider acceptor specificity than Bacillus macerans CGTase did and produced large amounts of transfer products of various acceptors such as D-galactose, D-mannose, D-fructose, D- and L-arabinose, D- and L-fucose, L-rhamnose, D-glucosamine, and lactose, which were inefficient acceptors for B. macerans CGTase. The main component of the smallest transfer products of lactose was assumed to be alpha-D-glucosyl O-beta-D-galactosyl-(1----4)-beta-D-glucoside.

Abstract OT3-2-03: An efficacy and safety trial of preoperative chemo-endocrine therapy in luminal B (HER2-negative) breast cancer: A prospective multi-institutional study

Background: The St.Gallen consensus guideline recommends the sequential administration chemotherapy followed by of endocrine therapy as postoperative therapy for the higher risk ER-positive breast cancer patients based on results of a single study (Albain et al, Lancet 2009). In metastatic settings however, several trials conducted in the 1980's demonstrated that tumor response rates were higher when chemotherapy and tamoxifen were concomitantly administered, than when chemotherapy and tamoxifen administered were given sequentially. In the preoperative settings, pathological complete response (pCR) rate can be used a surrogate marker to predict event-free survival or overall survival in Luminal B(HER2-negative) breast cancer. We therefore designed a prospective randomized safety and efficacy trial in order to test a hypothesis that the concomitant administration of an aromatase inhibitor and chemotherapy improves pathological complete response(pCR) rate than chemotherapy alone in the preoperative setting.

Trial design: The trial is a prospective, multi-center, randomized comparison of chemotherapy alone versus concomitant chmo-endocrine therapy evaluating the efficacy in terms of pCR rate and safety in preoperative settings in patients with Luminal B (HER2-negative) breast cancer. 94 patients were to be accrued into this trial.

- arm A (control): 12 cycles of weekly paclitaxel(80mg/m2) followed by 4 cycles of every 3-week AC(Doxorubicine 60mg/m2, Cyclophosphamide 600mg/m2).

- arm B (experimental): The same chermotherapy as arm A and anastrozole in postmenopausal patients or anastrozole+leuprolerine in premenopansal patients.

Eligibility criteria: 1)Female patients with operable and histologically confirmed invasive breast cancer; 2)HER2-negative; 3)Either ER -positive or PgR-positive; 4)Either Ki67-LI&gt; = 14% and NG&gt; = 2 or NG = 3 regardless of Ki67-LI.

Endpoints : Primary endpoint is the pCR rate. Secondary endpoints are the clinical response rate(RECIST), the adverse events(CTC-AE ver.4.0), the breast conserving rate and the health related quality of life.

Statistical Considerations : The pCR rates in the control arm and the experimental arm are expected to be 10% and 25%, respectively. In order to show the superiority of the experimental arm with an alfa error at 5% and beta error at 20%, calculated number of patients needed were 96.

Present Accrual and Target Accrual: As of June 06, 2013, 18 patients were enrolled from 8 institutions.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr OT3-2-03.

Increased polyamine intake inhibits age-associated alteration in global DNA methylation and 1,2-dimethylhydrazine-induced tumorigenesis

Polyamines (spermine and spermidine) play many important roles in cellular function and are supplied from the intestinal lumen. We have shown that continuous high polyamine intake inhibits age-associated pathologies in mice. The mechanism by which polyamines elicit these effects was examined. Twenty-four week old Jc1:ICR male mice were fed one of three experimental chows containing different polyamine concentrations. Lifetime intake of high polyamine chow, which had a polyamine content approximately three times higher than regular chow, elevated polyamine concentrations in whole blood, suppressed age-associated increases in pro-inflammatory status, decreased age-associated pathological changes, inhibited age-associated global alteration in DNA methylation status and reduced the mortality in aged mice. Exogenous spermine augmented DNA methyltransferase activity in Jurkat and HT-29 cells and inhibited polyamine deficiency-induced global alteration in DNA methylation status in vitro. In addition, increased polyamine intake was associated with a decreased incidence of colon tumors in BALB/c mice after 1,2-demethylhydrazine administration; 12 mice (60%) in the low polyamine group developed tumors, compared with only 5 mice (25%) in the high polyamine group (Fisher's exact probability = 0.027, p = 0.025). However, increased polyamine intake accelerated the growth of established tumors; maximal tumor diameter in the Low and High groups was 3.85±0.90 mm and 5.50±1.93 mm, respectively (Mann-Whitney test, p = 0.039). Spermine seems to play important roles in inhibiting age-associated and polyamine-deficient induced abnormal gene methylation as well as pathological changes including tumorigenesis.

Human breast cancer tissues contain abundant phosphatidylcholine(36∶1) with high stearoyl-CoA desaturase-1 expression

Breast cancer is the leading cause of cancer and mortality in women worldwide. Recent studies have argued that there is a close relationship between lipid synthesis and cancer progression because some enzymes related to lipid synthesis are overexpressed in breast cancer tissues. However, lipid distribution in breast cancer tissues has not been investigated. We aimed to visualize phosphatidylcholines (PCs) and lysoPCs (LPCs) in human breast cancer tissues by performing matrix assisted laser desorption/ionization-imaging mass spectrometry (MALDI-IMS), which is a novel technique that enables the visualization of molecules comprehensively. Twenty-nine breast tissue samples were obtained during surgery and subjected to MALDI-IMS analysis. We evaluated the heterogeneity of the distribution of PCs and LPCs on the tissues. Three species [PC(32∶1), PC(34∶1), and PC(36∶1)] of PCs with 1 mono-unsaturated fatty acid chain and 1 saturated fatty acid chain (MUFA-PCs) and one [PC(34∶0)] of PCs with 2 saturated fatty acid chains (SFA-PC) were relatively localized in cancerous areas rather than the rest of the sections (named reference area). In addition, the LPCs did not show any biased distribution. The relative amounts of PC(36∶1) compared to PC(36∶0) and that of PC(36∶1) to LPC(18∶0) were significantly higher in the cancerous areas. The protein expression of stearoyl-CoA desaturase-1 (SCD1), which is a synthetic enzyme of MUFA, showed accumulation in the cancerous areas as observed by the results of immunohistochemical staining. The ratios were further analyzed considering the differences in expressions of the estrogen receptor (ER), human epidermal growth factor receptor 2 (HER2), and Ki67. The ratios of the signal intensity of PC(36∶1) to that of PC(36∶0) was higher in the lesions with positive ER expression. The contribution of SCD1 and other enzymes to the formation of the observed phospholipid composition is discussed.

Thyroid remnant ablation with 1110MBq of 131I in outpatients: measurement of effective dose to household members and establishment of safety precautions

AIM

The aim of this study was to establish and confirm the safety of administering 1110MBq of 131I to outpatients.

METHODS

Total radiation exposure from patients to household members was hypothesized from the measured dose rate at 1 m when the patient is released. Actually we also measured the effective dose to household members who assisted outpatients during the first 7 days after the administration of 131I by personal dosimeter. A list of radiation safety precautions is given to the patient and household members. Behavioral reports about the distances and times of close contact throughout the 7 days are requested of each household member.

RESULTS

The effective dose measured using the personal dosimeter to all household members employing several safety precautions was confirmed to be lower than the hypothesized dose calculated using our formula. And the mean whole-body effective dose rate over the 7 days in household members was 0.05±0.08 (range, 0.05 to 0.43) mSv, which specify that radiation exposure to household members of the outpatients who have just received ablative radiation therapy must be below 5.0 mSv/event.

CONCLUSION

Remnant thyroid ablation with 1110MBq for outpatients showed that the radiation doses to household members were within the recommended constraint dose according to several safety precautions. The method of returning home after remnant thyroid ablation is thought to be the most important factor that determines the effective dose to household members of outpatients.

Two cases of diabetic mastopathy: MR imaging and pathological correlation

Diabetic mastopathy is a rare benign condition associated with long-standing diabetes mellitus and presents with breast lumps. This report describes two cases in which diffusion-weighted images (DWI) on magnetic resonance imaging were quite different from each other. In case 1, there were hyperintense lesions on DWI, and surgically removed specimens revealed ductitis with marked lymphocytic infiltration. In case 2, no abnormal intensity was depicted on DWI, and biopsy specimens showed dense stromal fibrosis with mild perivascular lymphocytic infiltration that corresponded to previous reports. Although it is reported that diabetic mastopathy is composed of dense fibrous tissue with low cellularity that results in no hyperintense lesion on DWI, in cases with marked lymphocytic infiltration, strong hyperintensity can be seen on DWI mimicking malignant breast tumors.

The accumulation of DNA demethylation in Sat α in normal gastric tissues with Helicobacter pylori infection renders susceptibility to gastric cancer in some individuals

Helicobacter pylori (HP) infection is widely recognized as a risk factor for gastric cancer, but only a minority of infected individuals develop gastric cancer. The aim of this study was to determine whether DNA demethylation in non-cancerous gastric mucosa (NGM) significantly enhances susceptibility to gastric cancer. A total of 165 healthy volunteers, including 83 HP-positive and 82-negative individuals, as well as 83 patients with single and 18 with synchronous double gastric cancer (GC) were enrolled in this study. The relative demethylation levels (RDLs) of repetitive sequences, including Alu, LINE-1 and Sat α, were quantified by real-time methylation-specific polymerase chain reaction. The Alu RDL did not exhibit any differences within each respective group, whereas LINE-1 RDL was significantly elevated in cancer tissues compared with the NGM in the other groups (P<0.001). Our results indicated that a gradual increase in Sat α RDL correlated with HP infection and cancer development. Sat α RDL was significantly elevated in the NGM in HP-positive compared with HP-negative (P<0.001), and significantly elevated in cancer tissues (P<0.001). Although the Sat α RDL of the NGM in the total population increased in an age-dependent manner, it was significantly increased in a fraction of younger GC patients (<45 years) compared with all of the others (45 years or older, P=0.0391). In addition, double GC exhibited a significantly higher Sat α RDL in the NGM compared with single GC (P=0.0014). In these two fractions, Sat α RDL in the NGM exhibited an inverse correlation with age. In conclusion, the present study demonstrated that the accumulation of DNA demethylation in Sat α RDL in the NGM with HP infection potentially renders susceptibility to gastric cancer in a fraction of GC patients younger than 45 years or in patients with multiple cancers.

Aberrant methylation of PSD disturbs Rac1-mediated immune responses governing neutrophil chemotaxis and apoptosis in ulcerative colitis-associated carcinogenesis

We previously reported that the Pleckstrin and Sec7 domain-containing (PSD) gene is preferentially methylated in patients with ulcerative colitis (UC) who developed colorectal cancer (CRC), and is implicated in UC-associated carcinogenesis through its inhibition of apoptosis. This study aimed to determine the potential effect of PSD methylation on its downstream molecule, Ras-related C3 botulinum toxin substrate 1 (Rac1), which governs neutrophil chemotaxis and apoptosis signaling. PSD was knocked down in a normal human fibroblast cell line (HNDF) and a neutrophil-like cell line (HL-60). Both NHDF and HL-60 cells exhibited numerous filamentous-actin (F-actin) rich membrane extensions, resulting in the activation of Rac1; this activation was hampered by PSD silencing. Lipopolysaccharide, a reactive oxygen species (ROS) inducer, stimulated NHDF cells to release ROS and activated caspase‑3/7 in the presence of neutrophils, which was inhibited by PSD knockdown. Migration assays demonstrated that chemotaxis of HL-60 cells was affected by PSD silencing in NHDF cells. Tissue sections from 6 UC patients with CRC and 15 UC patients without CRC were examined. To verify Rac1-mediated chemotaxis in tissue sections, we evaluated the grade of neutrophil infiltration by histological assessment and assessed F-actin and PSD expression by immunohistochemistry. Neutrophil infiltration, F-actin and PSD expression were significantly decreased in specimens from UC patients with PSD methylation compared with those without. Decreased levels of F-actin expression were observed in colorectal mucosa, as well as in infiltrating cells with PSD methylation. PSD expression was preferentially inhibited in colorectal mucosa by PSD methylation, whereas PSD expression was rarely observed in infiltrating cells, regardless of PSD methylation status. These data indicate that aberrant methylation of PSD occurs in UC-associated colorectal mucosa, enabling circumvention of Rac1-mediated immune responses governing neutrophil chemotaxis and apoptosis, and thus plays a pivotal role in the mechanisms underlying UC-associated carcinogenesis.

P4-05-05: Imaging Mass Spectrometry Based Lipid Metabolites Analysis for Breast Cancer

Background: Activation of lipid metabolism is an early event of carcinogenesis and a central hallmark of many cancers including breast cancer. Recent findings argue that stearoyl CoA desaturase-1 (SCD1), a key regulator of the fatty acid (FA) composition and the endoplasmic reticulum resident enzyme that converts saturated FA (SFA) into monounsaturated FA (MUFA) is a novel regulator of carcinogenesis. The distinctive lipids composition of membrane in cancer cells and the biological functions of SCD1, however, still remain uncertain. Imaging mass spectrometry (IMS) is a mass spectrometry-based analyzing technique that enables visualization of the individual molecules without requiring antibodies. It allows comprehensive detection of a wide range of biomolecules, such as lipids. We attempted to visualize the localization of lipids in breast cancer by IMS for better understanding of cancer proliferation.

Materials and methods: 13 specimens were obtained from the primary breast cancer patients. All were Japanese woman and aged 41–86 years (mean 61.5y.o.). Only one patient received preoperative systematic therapy. 6 were estrogen receptor (ER) and/or progesterone receptor (PgR) positive and human epidermal growth factor receptor 2 (HER2) negative, 2 were ER and/or PgR positive and HER2 positive, 2 were both ER and PgR negative and HER2 positive and 2 were triple negative.

IMS: Samples were immediately chilled in liquid Hexan and stored at −80°. All specimens were sliced into 10 mm thin sections, mounted onto one indium-tin oxide-coated glass slides (Bruker Daltonics) and then sprayed by 2,5-Dihydroxybenzoic acid. Matrix assisted laser desorption ionization (MALDI) technique was used as a soft ionization method. We used time of flight (TOF)/TOF type instrument (Ultraflex, Bruker Daltonics) and all the spectrum were acquired automatically using Fleximaging software (Bruker Daltonics). Each spectral intensity at any mass-to-charge ratio (m/z) was measured at 16 regions of interest (ROI); 13 ROI were picked up from cancerous parts and 3 were from non-cancerous parts. Spectral intensities were compared and statistical analysis was performed by Mann Whitney test. The software was also used to create two-dimensional ion-density maps.

Results: In the cancerous parts of all the 13 specimens, two distinct peaks of the molecular ions were detected at m/z 798.5 and 810.5, which were not found in the non-cancerous parts. Median intensity of the molecular ions at m/z 798.5 and 810.5 were 38.9 and 3.18 in the cancerous part, while they were 0.84 and 1.02 in the non-cancerous part (p=0.010 and 0.015, respectively). Tandem mass spectrometry analysis for these two molecules revealed that they were two kinds of phosphatidylcholine (PC), PC (16:0/18:1) and PC (18:0/18:1). Localization of the individual PC was visualized by means of IMS, which showed that in cancerous part accumulation of PCs containing MUFA was more pronounced than those containing SFA only. Conclusion:

Two kinds of PC containing MUFA were found to highly accumulate in cancerous parts, which may suggest involvement of SCD1 in the membrane composition regulation and cancer proliferation. Further studies may thus be warranted to explore the relation between PC localization and the SCD1 expression.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-05-05.

OT2-03-03: Spectroscopic Feature of Breast Cancer

Objectives: To examine optical properties of breast cancer by time-resolved spectroscopy.

Materials and Methods: We irradiated a pulsed laser of 760, 800, and 830 nm wave-length lights at multiple sites of both breasts including the site just above the cancer and detected the light transmitted through the breast with TRS-20SH (Hamamatsu Photonics K.K.). Absorption coefficient (μa), reduced scattering coefficient (μs'), total hemoglobin (tHb), and oxygen saturation (SO2) of the breast were calculated by photon diffusion equation. The clinical trial started in January 2007. A total of one hundred nine breast cancer patients participated in the trial and written informed consent were obtained from all of the patients. Results: In 800 nm wave-length, absorption coefficient (μa) of breast cancer tissue was significantly high, compared with contra-lateral normal breast (cancer:0.0677± 0.0293, normal breast;0.0479± 0.0161, p&lt;0.001).

Array-based identification of common DNA methylation alterations in ulcerative colitis

Patients with long-standing ulcerative colitis (UC) have higher risk of developing colorectal cancer. Albeit the causes remain to be understood, epigenetic alterations have been suggested to play a role in the long-term cancer risk of these patients. In this work, we developed a novel microarray platform based on methylation-sensitive amplified fragment length polymorphism (MS-AFLP) DNA fingerprinting. The over 10,000 NotI sites of the human genome were used to generate synthetic primers covering these loci that are equally distributed into CpG rich regions (promoters and CpG islands) and outside the CpG islands, providing a panoramic view of the methylation alterations in the genome. The arrays were first tested using the colon cancer cell line CW-2 showing the reproducibility and sensitivity of the approach. We next investigated DNA methylation alterations in the colonic mucosa of 14 UC patients. We identified epigenetic alterations affecting genes putatively involved in UC disease, and in susceptibility to develop colorectal cancer. There was a strong concordance of methylation alterations (both hypermethylation and hypomethylation) shared by the cancer cells of the CW-2 cell line and the non-cancer UC samples. To the best of our knowledge, this work defines the first high-throughput aberrant DNA methylation profiles of the colonic mucosa of UC patients. These epigenetic profiles provide novel and relevant knowledge on the molecular alterations associated to the UC pathology. Some of the detected alterations could be exploited as cancer risk predictors underlying a field defect for cancerization in UC-associated carcinogenesis.

Aberrant methylation of the Pleckstrin and Sec7 domain-containing gene is implicated in ulcerative colitis-associated carcinogenesis through its inhibitory effect on apoptosis

The Pleckstrin and Sec7 domain-containing (PSD) gene, which regulates skeletal rearrangements, has been found to be more frequently methylated both in ulcerative colitis (UC)-associated colorectal cancer tissues (5 of 7; 71.4%) and matched normal epithelia (4 of 7; 57.1%) compared to non-neoplastic UC epithelia (6 of 22; 27.3%) and sporadic colorectal cancer tissues (6 of 32; 18.8%). The levels of PSD mRNA were positively correlated with the methylation status of PSD, as shown by both MSP and bisulfite sequencing. To determine the potential role of PSD silencing in the mechanisms underlying UC-associated carcinogenesis, the levels of senescence, proliferation and apoptosis were evaluated in a normal human fibroblast cell line (NHDF) in which 93% of PSD expression was knocked down by a small-interfering RNA (si-RNA). Although there were no significant differences in the levels of senescence and proliferation caused by PSD knockdown, the level of apoptosis was significantly decreased by PSD knockdown (5.3% in siControl-treated cells vs. 0.67% in siPSD-treated cells, p=0.0001). In addition, reactive oxygen species inducers accelerated apoptosis in NHDF and a neutrophil-like cell line, which was significantly reduced by PSD knockdown. To verify the effect of PSD methylation in tissue sections including 21 samples from UC patients with or without tumors, we elucidated PSD promoting accumulation of filamentous-actin (F-actin) and apoptosis by immunohistochemistry and TUNEL assay, respectively. Both levels of accumulation of F-actin and apoptosis were significantly decreased in specimens from UC patients with PSD methylation compared to those without PSD methylation (F-actin: 0.69±0.86 with vs. 1.57±0.51 without, p=0.0031, apoptotic index: 0.31±0.63 with vs. 1.0±0.88 without, p=0.0277). In conclusion, our results indicate that PSD methylation plays a significant role in the mechanisms underlying UC-associated carcinogenesis through its inhibitory effect on apoptosis in the interaction between colorectal mucosa and neutrophils.

Identification of a potent epigenetic biomarker for resistance to camptothecin and poor outcome to irinotecan-based chemotherapy in colon cancer

Drug resistance remains a major obstacle to successful cancer treatment. Genome-wide comprehensive analysis identified a novel gene, glucocorticoid-induced protein-coding gene (DEXI), which was frequently methylated in colorectal (CRC; 36 of 73 patients; 49%) and gastric (28 of 89 patients; 31%) cancer patients. Here, we show that DEXI methylation is implicated in mechanisms facilitating resistance to camptothecin (CPT) via inhibition of apoptosis. Silencing of DEXI by siRNA significantly reduced CPT-induced apoptosis in a fibroblast cell line (1/6-fold; p<0.01) originally expressing endogenous DEXI. Restored expression of DEXI by 5-aza-2'-deoxycytidine (DAC) significantly enhanced susceptibility to CPT (3-fold; p<0.01) in a colon cancer cell line originally suppressing endogenous DEXI due to almost complete methylation. Exogenous induction of DEXI confirmed that DEXI per se contributed to enhanced susceptibility to CPT. 5-Fluorouracil (5-FU) did not exhibit these synergistic effects by DEXI restoration. Further, to estimate the clinical usefulness of DEXI methylation status as biomarker for drug resistance to irinotecan (CPT-11), 16 CRC patients who underwent FOLFIRI (5-FU + CPT-11) therapy because they were refractory to FOLFOX (5-FU + oxaliplatin) were analyzed. Significantly poor response and outcome were observed in 8 CRC patients harboring DEXI methylation. In 8 CRC patients harboring DEXI methylation disease control rate, progression-free survival and overall survival were 25.0%, 2 and 11.8 months, respectively, whereas in 8 CRC patients without DEXI methylation they were 62.5%, 5.3 and 15 months, respectively (p<0.01). These significant differences were not observed in patients undergoing treatment with FOLFOX. In conclusion, silencing of DEXI leads to resistance, but restored expression enhances susceptibility to CPT in vitro and DEXI methylation results in poor response and outcome to CPT-11-based chemotherapy, suggesting that DEXI is a potent therapeutic target and an epigenetic biomarker for the selection of patients more likely to benefit from CPT-11-based chemotherapy.

Giant Rashba-type spin splitting in bulk BiTeI

There has been increasing interest in phenomena emerging from relativistic electrons in a solid, which have a potential impact on spintronics and magnetoelectrics. One example is the Rashba effect, which lifts the electron-spin degeneracy as a consequence of spin-orbit interaction under broken inversion symmetry. A high-energy-scale Rashba spin splitting is highly desirable for enhancing the coupling between electron spins and electricity relevant for spintronic functions. Here we describe the finding of a huge spin-orbit interaction effect in a polar semiconductor composed of heavy elements, BiTeI, where the bulk carriers are ruled by large Rashba-like spin splitting. The band splitting and its spin polarization obtained by spin- and angle-resolved photoemission spectroscopy are well in accord with relativistic first-principles calculations, confirming that the spin splitting is indeed derived from bulk atomic configurations. Together with the feasibility of carrier-doping control, the giant-Rashba semiconductor BiTeI possesses excellent potential for application to various spin-dependent electronic functions.

Effect of transplantation of pro-angiogenic monocytes to pancreatic cancer-bearing mice on resistance to chemotherapy/radiotherapy

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Background: Hypoxic tumors are usually resistant to conventional chemotherapy and radiotherapies, which typically target actively dividing cells. The tumor vasculatures are unorganized and lack adequate pericyte coverage, which compromises delivery of drugs to tumors. How best to normalize the aberrant tumor vasculature to maximize anticancer drug delivery comprises an area of intensive investigation.

Methods: We tested out hypothesize that bone marrow (BM) cells may be able to restore appropriate vessel function in tumor vasculature using nude mice bearing pancreatic cancer xenografts and genetically engineered mice that develop pancreatic adenocarcinoma.

Results: Culturing BM mononuclear cells with endothelial growth medium resulted in the early outgrowth of spindle-shaped attached monocytic cells expressing CD11b/CXCR4 with a significant vessel stabilizing activity. Intravenous administration of these cultured pro- angiogenic cells into mice bearing pancreatic cancer significantly reduced areas of hypoxia without enhancing tumor growth. The resulting vasculature structurally mimicked normal vessels with intensive pericyte coverage. Consistent with a marked reduction in gene expressions involved in drug resistance such as MDR1 and ABCG2 in monocytes-injected tumors, a combination of the transplantation and chemotherapeutic agents reduced tumor size and significantly increased areas of necrosis as compared to chemotherapy alone.

Conclusions: Our findings offer an alternate approach to improve delivery and efficacy of anticancer drugs to hypoxic tumors through a remodeling of the abnormal tumor vessels.

No significant financial relationships to disclose.

A case of non-traumatic subgaleal hematoma effectively treated with endovascular surgery

Non-traumatic subgaleal hematoma is very rare. We present a case of refractory non-traumatic subgaleal hematoma occurring in a 15-year-old male patient. The patient was successfully treated by embolization of the superficial temporal artery. This therapeutic approach to refractory non-traumatic subgaleal hematoma is discussed.

EMX2 is epigenetically silenced and suppresses growth in human lung cancer

Lung cancer is a common cancer and the leading cause of cancer-related death worldwide. Aberrant activation of WNT signaling is implicated in lung carcinogenesis. EMX2, a human homologue of the Drosophila empty spiracles gene is a homeodomain-containing transcription factor. The function of EMX2 has been linked to the WNT signaling pathway during embryonic patterning in mice. However, little is known about the role of EMX2 in human tumorigenesis. In this study, we found that EMX2 was dramatically downregulated in lung cancer tissue samples and this downregulation was associated with methylation of the EMX2 promoter. Restoration of EMX2 expression in lung cancer cells lacking endogenous EMX2 expression suppressed cell proliferation and invasive phenotypes, inhibited canonical WNT signaling, and sensitized lung cancer cells to the treatment of the chemo cytotoxic drug cisplatin. On the other hand, knockdown of EMX2 expression in lung cancer cells expressing endogenous EMX2 promoted cell proliferation, invasive phenotypes and canonical WNT signaling. Taken together, our study suggests that EMX2 may have important roles as a novel suppressor in human lung cancer.

Expression of a Rho guanine nucleotide exchange factor, Ect2, in the developing mouse pituitary

The pituitary gland is a highly mitotically active tissue after birth. Various cell types are known to undergo proliferation in the anterior pituitary. However, little is known about the mechanisms regulating mitotic activity in this tissue. When searching for genes specifically expressed in the pituitary gland among those that we previously screened in Drosophila, we found epithelial cell-transforming gene 2 (Ect2). Ect2 is a guanine nucleotide exchange factor for Rho GTPases, which is known to play an essential role in cytokinesis. Although there have been many cellular studies regarding the function of Ect2, the temporal and spatial expression patterns of Ect2 in vivo have not been determined. In the present study, we examined the postnatal developmental expression of Ect2 in the mouse pituitary. Enhanced Ect2 expression was detected in the mouse pituitary gland during the first 3 weeks after birth, which coincided well with the period of rapid pituitary expansion associated with increased growth rate. Immunostaining analysis showed that Ect2-expressing cells were distributed in the anterior and intermediate lobes, but not the posterior lobe, of the pituitary. These Ect2-expressing cells frequently incorporated the thymidine analogue, EdU (5-ethynyl-2'-deoxyuridine), indicating that these cells were mitotically active. Taken together, the results demonstrate the functional role of Ect2 in postnatal proliferating cells in the two lobes of the pituitary, thereby suggesting roles in developmental growth of the mammalian pituitary.