Surface and Aggregation Behavior of Pentablock Copolymer PNIPAM7-F127-PNIPAM7 in Aqueous Solutions

The triblock Pluronic F127 was modified by introducing poly(N-isopropylacrylamide) (PNIPAM) at both the poly(ethylene oxide) ends, and the pentablock copolymer so-prepared was characterized by gel permeation chromatography and (1)H NMR. The degree of polymerization of NIPAM blocks at the two ends was 7. The solution behavior and microstructure of copolymer aggregates in water and aqueous salt solution were examined and compared with F127 by UV-visible absorption spectroscopy, microdifferential scanning calorimetry, dynamic light scattering (DLS), and small-angle neutron scattering (SANS). The behavior of the pentablock copolymer at the air/water interface was determined by Langmuir film balance. Two lower critical solution temperatures were observed for pentablock copolymer, corresponding to poly(propylene oxide) and PNIPAM blocks, respectively. DLS studies show that micelle size increased with increase in temperature and in the presence of salt. SANS measurements provided temperature-dependent structural evolution of copolymer micelles in water and salt solution. The copolymer displays an isotherm with four classical regions (pancake, mushroom, brush, and condensed state). The study has potential applications in controlled drug delivery due to the tunable phase behavior and biocompatibility of the copolymer.

Catastrophic antiphospholipid syndrome associated with malignancies (case report and review of the literature)

We describe a 58-year old female patient with rapid development of arterial and venous thromboembolisms, including deep vein thrombosis (DVT) in the lower limbs, recurrent cerebral infarctions and bilateral pulmonary emboli. Her laboratory data on admission showed positive anticardiolipin antibody of IgG isotype (IgG aCL) and positive anti-β2 glycoprotein-I antibody of IgG isotype (IgG aβ2-GPI), and decreased protein C activity and protein S antigen. Systemic examinations revealed the presence of an ovarian cancer. Surgical resection was attempted, but her cancer infiltrated the pelvic wall and could not be resected. Despite treatment with unfractionated heparin followed by warfarin, she died due to recurrent episodes of cerebral infarction.

This case was considered as probable catastrophic antiphospholipid syndrome (CAPS), which might be associated with ovarian cancer. Known as Trousseau's syndrome, arterial and, more commonly, venous thrombosis is a frequent complication of cancer and sometimes a harbinger of occult cancer. Our case indicates that there is an overlap between antiphospholipid syndrome (APS) and Trousseau's syndrome. It is important to bear in mind that a thrombotic event associated with cancer can be the first manifestation of CAPS.

Morphofunctional Merits of an In Vivo Cryotechnique for Living Animal Organs: Challenges of Clinical Applications from Basic Medical Research

Recent advances in molecular and genetic techniques have led to establishment of new biomedical fields; however, morphological techniques are still required for a more precise understanding of functioning cells and tissues. Conventional preparation procedures involve a series of chemical fixation, alcohol dehydration, paraffin or epoxy resin embedding, sectioning, and staining steps. In these steps, technical artifacts modify original morphologies of the cells being examined. Furthermore, difficulties are associated with capturing dynamic images in vivo using conventional chemical fixation. Therefore, a quick-freezing (QF) method was introduced for biological specimens in the 20th century. However, specimens have to be resected from living animal organs with blood supply, and their dynamical morphologies have not been investigated in detail using the QF method. In order to overcome these issues, the tissue resection step of organs had to be avoided and samples needed to be frozen under blood circulation. Our in vivo cryotechnique (IVCT) was an original technique to cryofix samples without resecting their tissues. The most significant merit of IVCT is that blood circulation into organs is preserved at the exact moment of freezing, which has been useful for arresting transient physiological processes of cells and tissues and maintaining their components in situ.

Abstract P5-08-47: Clinical outcome of pathological T1N0 breast cancer according to the hormone receptor and HER2 status and adjuvant therapy

Background: The outcome of T1N0 breast cancer is relatively good, however, a subpopulation of this stage has a high population of relapse. It is important to clarify the factors associated with the outcome in order to determine the adequate adjuvant systemic therapy for T1N0 breast cancer.

Aims: To investigate the prognosis of pathological T1N0 (pT1N0) breast cancer by receptor (estrogen receptor; ER, progesterone receptor; PgR, human epidermal growth factor receptor 2; HER2) status and adjuvant systemic therapy, and thus to identify the factors associated with the outcome.

Methods: Among 2164 women who underwent surgery for primary breast cancer in our department, 925 had pathological T1N0 tumors (130 T1a, 234 T1b and 561 T1c). The associations between clinicopathological characteristics, adjuvant therapy and relapse-free survival (RFS) were examined

Results: Of 908 patients with known hormone receptor (HR; ER and PgR) and HER2 status, 675, 79, 64 and 90 had HR+/HER2-, HR+/HER2+, HR-/HER2+ and HR-/HER2- (triple negative; TN) tumors, respectively. The prognosis of patients with T1c tumors was significantly poorer than that of the patients with T1a and T1b tumors (5-year DFS of T1a, T1b and T1c: 97.5%, 97.9%, 94.5%, p=0.0201). HR+/HER2- subtype was significantly associated with better prognosis than other subtypes (5-year DFS: 96.9% vs. 93.6%, p=0.0194). Patients younger than 40 year old or older than 74 years old had significantly shorter PFS (p=0.0039). Lymphovessel invasion (ly), high histological grade (HG2, 3) were associated with poor outcome in all cohort (p=0.0026, p=0.0356). In HR-positive tumors, ly, high HG and omission of the adjuvant endocrine therapy were associated with shorter RFS (p=0.0009, p=0.0306 and p=0.0016, respectively). Adjuvant chemotherapy was not associated with RFS regardless of HR and HER2 status. However, in T1c with nuclear grade (NG) 3 tumors, use of the adjuvant chemotherapy was associated better prognosis. The prognosis of patients with HER2+ tumors was not significantly different among patients with or without trastuzumab in this cohort.

Conclusion: In spite of the excellent prognosis of pT1N0 breast cancer, adjuvant endocrine therapy is important for patients with HR+ tumors. However, the use of adjuvant chemotherapy or trastuzumab did not significantly improve the prognosis. Thus, the indication of chemotherapy or anti-HER2 therapy should be determined in consideration of the several prognostic factors for pT1N0 breast cancer.

Citation Format: Tokunaga E, Akiyoshi S, Koga C, Nakamura Y, Taguchi K, Ishida M, Ohno S. Clinical outcome of pathological T1N0 breast cancer according to the hormone receptor and HER2 status and adjuvant therapy. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-08-47.

Abstract P4-02-13: The pattern of tumor shrinkage is associated with prognosis in low grade luminal early breast cancer during neoadjuvant chemotherapy

BACKGROUND: In neoadjuvant chemotherapy (NAC) for early breast cancer, the pathological response rate in estrogen receptor (ER)-positive tumors has been low in comparison with those of ER-negative tumors. Therefore, surrogate makers other than the pCR rate are needed during NAC for luminal breast cancer. Using MRI, we analyzed the patterns of tumor shrinkage after NAC as a surrogate prognostic factor in low grade luminal breast cancer. METHODS: Of 854 patients who had received NAC in a single institute from Jan. 2000 to Dec. 2009, 183 patients with low grade luminal breast cancer were retrospectively evaluated for this study. They were defined as ER and/or PgR positive in more than 10% of cancer cells and HER2 negative (IHC 0, 1+ or FISH <2.0) with nuclear grade 1 and 2. RESULTS: The median observation period was 67.9 months following surgery, and recurrence was observed in 31 patients (16.9%). The median age was 49 (22-76) years. One hundred eighty patients received anthracycline-containing chemotherapy, and 158 received taxane. There were 16 deaths (8.7%) related to breast cancer. We categorized the patterns of tumor shrinkage by MRI into 6 types: concentric shrinkage (CS), diffuse decrease (DD), reduction to small foci (RSF), decrease of intensity only (DIO), no change (NC), and enlargement (EL). According to our categorization, CS occurred in 97 (53.0%), RSF in 7 (3.8%), DD in 62 (33.9%), DIO in 7 (3.8%), NC in 5 (2.7%), and EL in 5 (2.7%). As expected, there were statistically significant differences in both the median DFS and OS in each pattern of tumor shrinkage (p <0.001 and p=0.001, respectively); in particular, the CS pattern had excellent prognosis. Multivariate analysis demonstrated that concentric shrinkage was the only significant good prognostic factor for OS (p=0.015). CONCLUSIONS: Tumor shrinkage patterns as revealed by MRI could be important surrogate prognostic factors for NAC in early low grade luminal breast cancer.

Citation Format: Fukada I, Araki K, Kobayashi K, Gomi N, Horii R, Akiyama F, Takahashi S, Iiwase T, Ohno S, Ito Y. The pattern of tumor shrinkage is associated with prognosis in low grade luminal early breast cancer during neoadjuvant chemotherapy. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-02-13.

Abstract P4-12-02: Adjuvant trastuzumab improved the prognosis of HER2-positive early breast cancer: Single institutional cohort study from clinical practice

Background: Trastuzumab-containing regimens for the adjuvant treatment of human epidermal growth factor receptor 2 (HER2)-positive early breast cancer significantly improved the prognosis. However, most data showing the effects of trastuzumab come from clinical trials.

Aims: To evaluate the efficacy of the adjuvant trastuzumab in the clinical practice, the prognosis of HER2-positive early breast cancer was investigated according to the adjuvant treatment with or without trastuzumab.

Methods: Among 2548 women who underwent surgery for primary breast cancer in our department between 2000 and 2011, 315 patients had HER2-positive tumors. A total of 293 patients aged 75 or younger with invasive HER2-positive breast cancer were included in this study. The associations between clinicopathological characteristics, adjuvant therapy and relapse-free survival (RFS) were examined. The RFS was estimated using the Kaplan-Meier method, and independent predictors were assessed using proportional cox hazard models.

Results: 113 (38.5%) patients ware treated with chemotherapy alone (Cohort A), 100 (34.1%) patients were treated with chemotherapy and trastuzumab (Cohort B) and 80 (27.3%) patients received neither chemotherapy nor trastuzumab (Cohort C). The administration of adjuvant trastuzumab significantly increased in 2007. The prognosis of the patients treated in 2007-2011 was significantly better than that of patients treated in 2000-2006 (p=0.0011). The use of adjuvant trastuzumab was significantly associated with longer RFS (p=0.0286). The improvement of RFS by using trastuzumab was significant in node-positive patients. The patients in Cohort C had mainly node negative and small tumors. RFS of the patients treated of Cohort B was significantly more favorable than that of Cohort A. However, RFS of Cohort C was not statistically different from that of Cohort B, probably due to the early stage of Cohort C. In univariate analysis, larger tumor size (T2, 3), lymph node metastasis, lymphovessel invasion and absence of trastuzumab were related to relapse. In multivariate analysis, factors related to relapse were lymph node metastasis and absence of trastuzumab.

Univariate and multivariate analysis for relapse-free survivalFactorsUnivariate analysis Multivariate analysis  HR95% CIP valueHR95% CIP valueTumor sizeT2, T3 vs. T13.101.69-5.850.00021.820.87-3.950.1131LN meta.positive vs. negative4.372.26-8.84<0.00012.831.26-6.490.0116Histological grade3 vs. 1, 20.770.42-1.440.4199   lypositive vs. negativ3.401.87-6.25<0.00011.430.67-3.100.3538ERpositive vs. negativ0.930.50-1.650.7638   PRpositive vs. negativ0.970.50-1.760.8885   adjuvant chemotherapy 1.570.79-3.490.207   adjuvant trastuzumab 0.410.17-0.880.02070.410.16-0.900.0258LN meta.; lymph node metastasis, ly; lymphovessel invasion ER; estrogen receptor, PgR; progesterone receptor

Conclusions: Use of adjuvant trastuzumab improved the prognosis of HER2-positive early breast cancer in clinical practice.

Citation Format: Akiyoshi S, Ishida M, Koga C, Nakamura Y, Taguchi K, Ohno S, Tokunaga E. Adjuvant trastuzumab improved the prognosis of HER2-positive early breast cancer: Single institutional cohort study from clinical practice. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-12-02.

Abstract P5-13-05: The relationship between the expression of FOXA1 and GATA3 and the efficacy of neoadjuvant endocrine therapy

Background.

The estrogen receptor (ER)/ GATA3/ Forkhead box A1 (FOXA1) network is necessary for the ERα functional signature specific to luminal type breast cancers. High expression of FOXA1 indicates a good prognosis in ER-positive breast cancer. However, little is known about the association between the expression of FOXA1 and GATA3, and the efficacy of neoadjuvant endocrine therapy (NAE). This study investigated their predictive potential for NAE and the changes of their expression after NAE.

Methods.

The expression of ER, progesterone receptor (PgR), Ki67, FOXA1, and GATA3 were analyzed by immunohistochemistry in 66 patients with hormone receptor-positive/ human epidermal growth factor receptor 2 (HER2)-negative breast cancer who had been treated with NAE between March 2003 and December 2012 at Kyushu University Hospital, National Kyushu Cancer Center, and Sagara Hospital. The association between the expression of biological marker and the efficacy of NAE, and their expression changes after NAE were evaluated.

Results.

The median age of the patients was 60 years (range, 30–84 years). Pre- and post-menopausal patients were 24 (36.4%) and 42 (63.6%). Endocrine agents that were administered are as follows: aromatase inhibitors (AIs) for 42 patients (63.6%), luteinizing hormone-releasing hormone (LHRH) agonist plus AI for 10 patients (15.2%), LHRH agonist plus tamoxifen for 13 patients (19.7%). NAE yielded a partial response (PR) in 21 patients (31.8%) and stable disease (SD) in 45 patients (68.2%). Breast conserving surgery was performed in 56 patients (84.8%) and mastectomy was performed in 10 patients (15.2%). Preoperative Endocrine Prognostic Index (PEPI) score was 0 in 10 patients (15.2%) and 1 or greater (score 1 ≤) in 56 patients (84.8%).

Pre-treatment FOXA1 expression was positively correlated with GATA3 (P = 0.0003) and PgR (P = 0.0138). Post-treatment Ki67 expression was significantly lower in tumors, which achieved PR compared with those with SD (P = 0.0007). The expression of PgR, Ki67, and FOXA1 was significantly lower in post-treatment tumors compared with those in pre-treatment samples (p < 0.0001, p < 0.0001 and p < 0.0001, respectively). The expression of PgR, Ki67, and FOXA1 was significantly reduced in both tumors with PR and those with SD (PR: P = 0.0004, P < 0.0001, and P = 0.0417, respectively; SD: P < 0.0001, P = 0.0001, and P < 0.0001, respectively). The expression of PgR, Ki67, and FOXA1 was significantly decreased in post-treatment tumors in both patients with the PEPI score 0 and those with score 1 ≤ (score 0: P = 0.0078, P = 0.0059, and P = 0.0098, respectively; score 1 ≤: P < 0.0001, P < 0.0001, and P = 0.0002, respectively). In tumors with PgR > 20%, the expression of Ki67 and FOXA1 were significantly lower in post-treatment tumors (P < 0.0001 and P < 0.0001, respectively).

Conclusions.

FOXA1 expression correlated with PgR expression, and was reduced significantly after NAE. These results suggest that blocking the effect of estrogen might reduce FOXA1 expression.

Citation Format: Tanaka K, Tokunaga E, Inoue Y, Ueo H, Yamashita N, Sagara Y, Ohi Y, Taguchi K, Ohno S, Okano S, Kitao H, Oki E, Oda Y, Maehara Y. The relationship between the expression of FOXA1 and GATA3 and the efficacy of neoadjuvant endocrine therapy. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-13-05.

Abstract P6-07-10: Cytogenetic analysis of squamous cell carcinoma of the breast reveals inter- and intra-tumoral heterogeneity

Background: Squamous cell carcinoma (SCC) of the breast is a rare and generally aggressive disease constituting less than 0.1 % of all breast carcinomas. Although they have distinct morphological features, the origin and cytogenetic profiles of SCCs are still not well understood. In this study, five cases of SCC of the breast, three of which had an SCC component and an invasive or noninvasive ductal carcinoma of no special type (NST) component, were analyzed to evaluate their cytogenetic inter- and intra-tumoral heterogeneity.

Methods: Using a pathological database of approximately 3,000 patients with breast cancer, five patients with SCC were identified. Their medical records were retrospectively reviewed to obtain clinicopathological, radiological, therapeutic and prognostic information. The area largely consisting of the SCC component was macro-dissected from five 10 μm-thick sections and tumor DNA was extracted using the QIAmp DNA Mini Kit (Qiagen). Three cases contained a component of invasive or noninvasive ductal carcinoma of NST as well as an SCC component, and tumor DNA from NST components were also extracted as described above. Tumor DNA from each case were used for array comparative genomic hybridization (aCGH) analysis using a high-density oligonucleotide microarray (Agilent® SurePrint G3 8x60k microarray) and the cytogenetic profiles of SCC components were compared with each other and in three of the five cases with their paired NST components.

Results: Sufficient amounts of DNA were obtained for aCGH analysis with an average of 0.78 μg (0.39–1.35 μg). The quality of the aCGH was acceptable, as judged by the mean derivative log ratio spread (DLRSpread) of 0.45 (0.20–0.55), which estimates the log ratio noise by calculating the spread of log ratio differences between consecutive probes along all chromosomes. The cytogenetic profiles of SCC components showed large inter-tumoral heterogeneity with between 2 and 160 copy number alterations per case and no common copy number alterations were found among cases. Meanwhile, cytogenetic profiles were almost identical between paired SCC and NST components,. However, in one case, a large number of copy number aberrant (CNA) regions were detected in the SCC component compared with the NST component and all aberrations in the NST component were also present in the SCC component, which implies that the SCC component originated from the NST component. There were no common SCC-component-specific aberrations in the three cases with NST components.

Conclusion: These results demonstrate the degree of cytogenetic inter- and intra-tumoral heterogeneity in SCC of the breast. The comparison of cytogenetic profiles in one case indicated that the SCC component originated from the NST component.

Citation Format: Oikawa M, Igawa A, Ishida M, Nakamura Y, Nishimura S, Koga C, Akiyoshi S, Koi Y, Taguchi K, Ohno S, Tokunaga E. Cytogenetic analysis of squamous cell carcinoma of the breast reveals inter- and intra-tumoral heterogeneity. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-07-10.

Abstract P5-14-01: A meta-analysis of clinical benefit rates for fulvestrant 500 mg versus alternative therapies for treatment of postmenopausal, estrogen receptor-positive advanced breast cancer

Background

Fulvestrant 500 mg has demonstrated improved efficacy vs fulvestrant 250 mg (time to progression [TTP]/progression free survival [PFS] and overall survival) in the treatment of postmenopausal women with advanced breast cancer (ABC). Few clinical trials have demonstrated a significant increase in clinical benefit rate (CBR) for one endocrine therapy (ET) over another for the treatment of ABC. This implies that TTP/PFS improvements have been achieved principally by prolonging time to developing acquired resistance. However, it would be beneficial to know whether CBR is also improved, indicating that more patients experience tumor remission. We performed a meta-analysis to determine if there was a difference in CBR between fulvestrant 500 mg and its comparators in randomized clinical trials (RCTs).

Methods

Five RCTs evaluating fulvestrant 500 mg were included: CONFIRM, China CONFIRM, FINDER1 and FINDER2 (vs fulvestrant 250 mg) as second-line ET and FIRST (vs anastrozole) as first-line ET. CBR was calculated as the proportion of patients experiencing a best objective response of stable disease for ≥24 weeks, complete response or partial response. Peto method was used to calculate odds ratios (ORs), 95% confidence intervals (CIs) and p values. Separate fixed effect (FE) models were constructed for first- and second-line data combined, and for second-line only data. For each model Tarone's test for heterogeneity assessed the assumption of constant trial effect.

Results

Unadjusted ORs for CBR from CONFIRM, FINDER1 and FINDER2, adjusted OR for China CONFIRM (as reported in the trial publications), and combined FE models are shown (Table).The OR (95% CI) of the FE model for all trials indicated that CBR was higher with fulvestrant 500 mg than with comparator treatments (OR: 1.34 [1.12-1.61]; FE p=0.001; Tarone's test p=0.91). When assessing second-line ET only, the OR was similar to the overall combined analysis.

ORs (95% CI) of CBR from individual trials and meta-analysis. nOR of CBR for fulvestrant 500 mg vs comparator (95% CI)First-lineFIRST2051.30 (0.72–2.38)Second-lineCONFIRM7361.28 (0.95–1.71)China CONFIRM2211.37 (1.04–1.80)FINDER1921.20 (0.53–2.74)FINDER2931.96 (0.84–4.54)Fixed effects modelFirst- and second-line combined13471.34 (1.12–1.61) FE p=0.001; Tarone's test p=0.91Second-line only11421.35 (1.11–1.63) FE p=0.002; Tarone's test p=0.81CBR, clinical benefit rate; CI, confidence interval; FE, fixed effects model; OR, odds ratio. Adjusted odds ratio and CI (as reported in the trial publications) are presented for China CONFIRM; unadjusted odds ratios and CIs are used for all other trials. FINDER1 and FINDER2 included fulvestrant 500 mg, 250 mg plus loading dose, and 250 mg treatment arms. Data shown for fulvestrant 500 mg versus 250 mg.

Conclusions

These data suggest that fulvestrant 500 mg is associated with a significant improvement in CBR of approximately 34% compared with comparator ETs (i.e. more tumors are placed into remission). This finding is consistent in both second- and first-line ET settings. We await the results of the Phase 3 FALCON first-line ET RCT to see if it supports this finding of increased CBR with fulvestrant 500 mg.

Citation Format: Robertson JFR, Zefei J, Di Leo A, Ohno S, Pritchard KI, Ellis M, Bradbury I, Campbell C. A meta-analysis of clinical benefit rates for fulvestrant 500 mg versus alternative therapies for treatment of postmenopausal, estrogen receptor-positive advanced breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-14-01.

Synthesis of silsesquioxane-based element-block amphiphiles and their self-assembly in water

The self-assembly of silsesquioxane-based amphiphiles in water was investigated.

Involvement of membrane skeletal molecules in the Schmidt-Lanterman incisure in Schwann cells

Membrane skeletal networks form a two-dimensional lattice structure beneath erythrocyte membranes. 4.1R-MPP (membrane palmitoylated protein) 1-glycophorin C is one of the basic molecular complexes of the membrane skeleton. An analogous molecular complex, 4.1G-MPP6-cell adhesion molecule 4 (CADM4), is incorporated into the Schmidt-Lanterman incisure (SLI), a truncated cone shape in the myelin internode that is a specific feature of myelinated nerve fibers formed in Schwann cells in the peripheral nervous system. In this review, the dynamic structure of peripheral nerve fibers under stretching conditions is demonstrated using in vivo cryotechnique. The structures of nerve fibers had a beaded appearance, and the heights of SLI circular-truncated cones increased at the narrow sites of nerve fibers under the stretched condition. The height of SLI-truncated cones was lower in 4.1G-deficient nerve fibers than in wild-type nerve fibers. 4.1G was essential for the molecular targeting of MPP6 and CADM4 in SLI. The signal transduction protein, Src, was also involved in the 4.1G-MPP6-CADM4 molecular complex. The phosphorylation of Src was altered by the deletion of 4.1G. Thus, we herein demonstrate a membrane skeletal molecular complex in SLI that has potential roles in the regulation of adhesion and signal transduction as well as in structural stability in Schwann cells.

Immunohistochemical and morphofunctional studies of skeletal muscle tissues with electric nerve stimulation by in vivo cryotechnique

In this study, morphological and immunohistochemical alterations of skeletal muscle tissues during persistent contraction were examined by in vivo cryotechnique (IVCT). Contraction of gastrocnemius muscles was induced by sciatic nerve stimulation. The IVCT was performed immediately, 3 min or 10 min after the stimulation start. Prominent ripples of muscle fibers or wavy deformation of sarcolemma were detected immediately after the stimulation, but they gradually diminished to normal levels during the stimulation. The relative ratio of sarcomere and A band lengths was the highest in the control group, but it immediately decreased to the lowest level and then gradually recovered at 3 min or 10 min. Although histochemical intensity of PAS reaction was almost homogeneous in muscle tissues of the control group or immediately after the stimulation, it decreased at 3 min or 10 min. Serum albumin was immunolocalized as dot-like patterns within some muscle fibers at 3 min stimulation. These patterns became more prominent at 10 min, and the dots got larger and saccular in some sarcoplasmic regions. However, IgG1 and IgM were immunolocalized in blood vessels under nerve stimulation conditions. Therefore, IVCT was useful to capture the morphofunctional and metabolic changes of heterogeneous muscle fibers during the persistent contraction.

ELAS1-mediated inhibition of the cyclin G1-B'γ interaction promotes cancer cell apoptosis via stabilization and activation of p53

Radiation therapy (RT) is useful for selectively killing cancer cells. However, because high levels of ionizing radiation (IR) are toxic to normal cells, RT cannot be applied repeatedly to cancer patients. Therefore, novel chemicals that enhance the efficacy of chemoradiotherapy (CRT) would be valuable. Here, we report that ELAS1, a peptide corresponding to the protein phosphatase 2A (PP2A) association domain of cyclin G1 (CycG1), can enhance the efficacy of CRT. ELAS1 interacts with the PP2A B'γ-subunit and competitively inhibits association with CycG1, thereby preventing the PP2A holoenzyme from dephosphorylating target proteins, Mdm2 (pT218) and p53 (pS46), following DNA double-strand break (DSB) insults. Doxycycline (Dox)-induced overexpression of Myc-ELAS1 caused γ-irradiation to induce apoptosis in human osteosarcoma (U2OS) cells, at 1/10th the effective dosage of γ-irradiation required for apoptosis in Myc-vector-expressing cells; ELAS1 peptide incorporation into U2OS cells also showed similar apoptotic effects. Moreover, administration of DSB-inducing chemicals, camptothecin (CPT) or irinotecan, to Myc-ELAS1-expressing U2OS cells also induced efficient apoptosis with only 1/100th (CPT) or 1/5th (irinotecan) of the amounts of drugs required for this effect in Myc-vector-expressing cells. Taken together, ELAS1 may be important for the design of ELAS1-mimetic compounds to improve CRT efficacy.

Circulating tumour cell-derived plastin3 is a novel marker for predicting long-term prognosis in patients with breast cancer

BACKGROUND

Identification of promising biomarkers that predict the prognosis of patients with breast cancer is needed. In this study, we hypothesised that the expression of the epithelial-mesenchymal transition-related biomarker plastin3 (PLS3) in peripheral blood could be a prognostic factor in breast cancer.

METHODS

We examined PLS3 expression in breast cancer cell lines with epithelial and mesenchymal traits and in circulating tumour cells (CTCs) obtained from the peripheral blood of breast cancer patients. We investigated PLS3 expression in the peripheral blood of 594 patients with breast cancer to evaluate the clinical significance of PLS3 expression.

RESULTS

Robust PLS3 expression was observed in different breast cancer cell lines (Hs578t, MCF-7, MDA-MB-468, and MDA-MB-231) as well as in a bone marrow derived cancer cell line (BC-M1). In both the training (n=298) and validation (n=296) sets, PLS3 expression was observed in CTCs of patients with breast cancer. PLS3-positive patients showed significantly poorer overall and disease-free survival than PLS3-negative patients (P=0.0001 and 0.003, respectively). Subset analysis revealed that this prognostic biomarker was relevant in patients with stage I-III cancer, particularly in patients with luminal-type and triple-negative-type tumours.

CONCLUSIONS

These data demonstrated that PLS3 was expressed in CTCs undergoing the epithelial-mesenchymal transition in patients with breast cancer. Furthermore, PLS3 may be an excellent biomarker for identifying groups at risk of recurrence or with a poor prognosis.

Morphological and immunohistochemical analyses of soluble proteins in mucous membranes of living mouse intestines by cryotechniques

We have performed immunohistochemical or ultrastructural analyses of living mouse small intestines using Epon blocks prepared by 'in vivo cryotechnique' (IVCT). By electron microscopy, intracellular ultrastructures of epithelial cells were well preserved in tissue areas 5-10 μm away from cryogen-contact surface tissues. Their microvilli contained dynamically waving actin filaments, and highly electron-dense organelles, such as mitochondria, were seen under the widely organized terminal web. By quick-freezing of fresh resected tissues (FT-QF), many erythrocytes were congested within blood vessels due to loss of blood pressure. By immersion-fixation (IM-DH) and perfusion-fixation (PF-DH), small vacuoles were often seen in the cytoplasm of epithelial cells, and their intercellular spaces were also dilated. Moreover, actin filament bundles were irregular in cross sections of microvilli, compared with those with IVCT. Epon-embedded thick sections were treated with sodium ethoxide, followed by antigen retrieval and immunostained for immunoglobulin A (IgA), Ig kappa light chain (Igκ), J-chain and albumin. By cryotechniques, IgA immunoreactivity was detected as tiny dot-like patterns in cytoplasm of some epithelial cells. Both J-chain and Igκ immunoreactivities were detected in the same local areas as those of IgA. By FT-QF, however, the IgA immunoreactivity was more weakly detected, compared with that with IVCT. In thick sections prepared by IM-DH and PF-DH, it was rarely observed in both plasma and epithelial cells. Another albumin was diffusely immunolocalized in extracellular matrices of mucous membranes and also within blood vessels. Thus, IVCT was useful for preservation of soluble proteins and ultrastructural analyses of dynamically changing epithelial cells of living mouse small intestines.