OBP-401-GFP telomerase-dependent adenovirus illuminates and kills high-metastatic more effectively than low-metastatic triple-negative breast cancer in vitro

We previously described the development of a highly-invasive, triple-negative breast cancer (TNBC) variant using serial orthotopic implantation of MDA-MB-231 human breast cancer in nude mice. The isolated variant is highly invasive in the mammary gland and metastasized to lymph nodes in 10 of 12 mice compared with 2 of 12 of the parental cell line. OBP-401 is a telomerase-dependent cancer-specific, green fluorescent protein (GFP)-expressing adenovirus. OBP-401 was used to infect parental MDA-MB-231P cells and high-metastatic MDA-MB-231H and MDA-MB-231HLN isolated from a lymph node metastasis and MDA-MB-231HLM isolated from a lung metastasis. Time-course imaging showed that OBP-401 labeled MDA-MB-231HP, MDA-MB-231HLN, and MDA-MB-231HLM cells more brightly than MDA-MB-231 parental cells. OBP-401 killed MDA-MB-231H, MDA-MB-231HLN, and MDA-MB-231HLM cells more efficiently than MDA-MB-231P parental cells. These results indicate that OBP-401 could infect, label and then kill high-metastatic MDA-MB-231 more efficiently than low-metastatic MDA-MB-231.

Synergistic Effects of Streptococcal Glucosyltransferases on Adhesive Biofilm Formation

Glucosyltransferases (GTF)-I and GTF-SI of Streptococcus mutans synthesize water-insoluble and both water-soluble and -insoluble glucans, respectively, and play essential roles in the sucrose-dependent adhesion of the organism to tooth surfaces. To examine the interactions of different GTFs on artificial biofilm formed by S. mutans and other oral streptococci, we generated GTF-I- and GTF-SI-hyperproducing isogenic mutant strains. Transformant B42-21, which hyperexpressed GTF-SI, exhibited firm adhesion in the presence of sucrose, whereas transformant B42-10, which hyperexpressed GTF-I, failed to exhibit firm adhesion. Furthermore, co-culture of transformant B42-21 with water-soluble glucan-synthesizing Streptococcus sanguinis yielded firm adhesion, while the addition of dextran T10 to B42-21 growing culture had no effect on adhesion. These findings suggest that GTF-SI has a strong effect on sucrose-dependent adhesion and is essential for biofilm formation on smooth surfaces, in cooperation with water-soluble glucans synthesized de novo by oral streptococci that inherently lack cell adhesion ability.

RNA-binding protein Musashi2 induced by RANKL is critical for osteoclast survival

The Musashi family of RNA-binding proteins, Musashi1 and Musashi2, regulate self-renewal and differentiation of neuronal and hematopoietic stem cells by modulating protein translation. It has been recently reported that Musashi2, not Musashi1, regulates hematopoietic stem cells. Although osteoclasts are derived from hematopoietic cells, the expression and functions of Musashi proteins in osteoclast lineage cells remain unknown. In this study, we have uncovered that Musashi2 is the predominant isoform of Musashi proteins in osteoclast precursors and its expression is upregulated by receptor activator of NF-κB ligand (RANKL) during osteoclast differentiation. Knocking down the expression of Musashi2 in osteoclast lineage cells by shRNAs attenuates nuclear factor of activated T cells 1 (NFATc1) expression and osteoclast formation in vitro. Mechanistically, loss of Musashi2 inhibits Notch signaling during osteoclast differentiation and induces apoptosis in pre-osteoclasts. In contrast, depletion of Musashi2 has no effects on cell cycle progression and p21^WAF-1 protein expression in macrophages. Furthermore, depletion of Notch2 and its downstream target Hes1 in osteoclast precursors by shRNAs abrogates osteoclastogenesis by inhibiting NFATc1. Finally, absence of Musashi2 in osteoclast precursors promotes apoptosis and inhibits RANKL-induced nuclear factor-κB (NF-κB) activation, which is essential for osteoclast survival, Thus, Musashi2 is required for cell survival and optimal osteoclastogenesis by affecting Notch signaling and NF-κB activation.

Abstract P5-08-14: Tumor Infiltrating lymphocytes (TIL) related genomic signature associated with chemotherapy response and prognosis in subtypes of breast cancer

Background: Tumor infiltrating lymphocytes (TIL) in subtypes of breast cancer may provide clinically important information on chemotherapy response and prognosis. However, the standardized methodology for immunohistochemical (IHC)-TIL has not yet been established, reproducible and objective method of evaluation of TIL such as gene expression profiles is warranted. We evaluated whether IHC-TIL level was associated with gene expression profiles and whether such profiles could be used to predict chemotherapy response and prognosis according to subtypes of breast cancers.

Methods: To select TIL associated genes, we used 40 samples with both IHC-TIL information and gene expression profiling data. The degree of TIL at the edges of the tumor mass, in the tumor mass, or in the stroma surrounding the expanding mammary ducts packed by carcinoma cells was evaluated as score 0, 1, and 2, when TIL was not unrecognizable (0%), sparse (0 << 50%) and dense (50% ≤), respectively. We selected 22 genes as the TIL-gene signature (GS), by comparing expression profiles between TIL score 2 and 0 tumors. We showed the associations between the TIL-GS levels and subtypes of breast cancers (Estrogen receptor: ER / Human Epidermal growth factor 2: HER2). The chemotherapy sensitivity analysis was performed on cohorts of 625 patients with stage I–III breast cancer who received neo adjuvant chemotherapy (NAC) based on Anthracycline and Taxane containing regimen. Data from 1,586 tumors were used to evaluate the association between distant metastasis free survival (DMFS) and the TIL-GS in a Kaplan-Meier analysis.

Results: The TIL-GS for ER negative (-)/HER2- and HER2 positive (+) cases were significantly higher expression level than luminal types (p-value <0.001). All breast cancer subtypes except luminal-low proliferation had significantly higher differential TIL-GS level in cases with pathological complete response (pCR) after NAC than residual disease (luminal-high: p-value = 0.013, HER2+: 0.005, and ER-/HER2-: 0.016). With no adjuvant chemo or only tamoxifen treated breast cancer data set, the TIL-GS had no prognostic power in luminal cases regardless of proliferative level. In HER2+ breast cancers, cases with the high TIL-GS had significantly better prognosis than low cases (p-value =0.001), but no significance in ER-/HER2- cases (p-value = 0.621).

Conclusions: Higher TIL-gene signature of 22 genes appeared to be associated with aggressive subtypes and pCR rate (except luminal-low) of breast cancers. This approach may improve the reproducibility of assessment on tumor TIL level and thus serve the clinical applications for breast cancers.

Citation Format: Kochi M, Niikura N, Iwamoto T, Bianchini G, Mizoo T, Nogami T, Shien T, Motoki T, Taira N, Masuda S, Doihara H, Fujiwara T, Tokuda Y, Matsuoka J. Tumor Infiltrating lymphocytes (TIL) related genomic signature associated with chemotherapy response and prognosis in subtypes of 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 P5-08-14.

The global economic crisis, household income and pre-adolescent overweight and underweight: a nationwide birth cohort study in Japan

Background:

We hypothesized that children from lower income households and in households experiencing a negative income change in connection to the global economic crisis in 2008 would be at increased risk of adverse weight status during the subsequent years of economic downturn.

Methods:

Data were obtained from a nationwide longitudinal survey comprising all children born during 2 weeks of 2001. For 16,403 boys and 15,206 girls, information about anthropometric measurements and household characteristics was collected from 2001 to 2011 on multiple occasions. Interactions between the crisis onset (September 2008) and household income group, as well as the crisis onset and a >30% negative income change in connection to the crisis, were assessed with respect to risk of childhood over- and underweight.

Results:

Adjusted for household and parental characteristics, boys and girls in the lower household income quartiles had a larger increase in risk of overweight after the crisis onset relative to their peers in the highest income group. (Odds ratio (95% confidence interval) for interaction term in boys=1.23 (1.02–1.24); girls=1.35 (1.23–1.49) comparing the lowest with the highest income group.) Among girls, an interaction between the crisis onset and a >30% negative change in household income with respect to risk of overweight was observed (odds ratio for interaction term=1.23 (1.09–1.38)). Girls from the highest income group had an increased risk of underweight after the crisis onset compared with girls from the lowest income group.

Conclusions:

Boys and girls from lower household income groups and girls from households experiencing a negative income change in connection to the global economic crisis in 2008, may be at increased risk of overweight. Vulnerability to economic uncertainty could increase risk of overweight in preadolescence.