P3495Long-term engraftment of human CD271-positive adipose-derived stem cells with pericytic and less-aged gene profile in a mouse model of hindlimb ischemia

Background

Therapeutic angiogenesis using adipose-derived stem cells (ADSCs) is an attractive strategy for ischemic cardiovascular diseases. We previously reported that human CD271+ population of adipose-derived stem cells (ADSCs) promoted neovascularization with enhanced engraftment in a mouse model of hindlimb ischemia. However, whether and how CD271+ ADSCs promote the long-term engraftment is still uncertain.

Purpose

We aimed to examine whether the angiogenic effect and cell engraftment capacity of CD271+ ADSCs would be sustained in long-term period. Then, comparative gene profiling between CD271+ and CD271- ADSCs were analyzed. Finally, cell proliferation and endothelial differentiation assays were conducted.

Methods

ADSCs were isolated from subcutaneous adipose tissue of 5 patients received cardiovascular surgery. CD271+ and CD271- ADSCs were sorted from CD45-CD31-CD34+ ADSCs fraction by FACS sorting (Fig. A). Cultured CD271+ and CD271- ADSCs at passage 6 were labeled by PKH26 cell linker dye and used for xenograft experiments. Briefly, athymic nude mice were subjected to hindlimb ischemia and one million of human ADSCs were injected into the ischemic muscles. In control group, PBS was solely injected. At 2 and 5 weeks, neovascularization was evaluated by immunohistochemistry (capillary density using lectin perfusion). Cell engraftment was assessed by counting PKH26-positive cells. Furthermore, we compared gene profiling between CD271+ and CD271- ADSCs by microarray. Proliferative capacity was evaluated by colony-forming unit (CFU) assay with Giemsa staining. In endothelial differentiation assay, CD271+ and CD271- ADSCs were cultured in differentiation induction medium containing vascular endothelial growth factor for 2 weeks and stained with anti-human CD31 antibody.

Results

Cell therapy using CD271+ ADSCs demonstrated approximately 3-fold more enhanced neovascularization than those using CD271- ADSCs or PBS in histological analysis of capillary density at 2 weeks from cell therapy (Fig. B and C). At 5 weeks, mice treated with CD271+ ADSCs were significantly rescued from limb ischemia and this was accompanied by sustained engraftment of ADSCs (Fig. D). In microarray analysis, the differentially expressed 2167 genes were extracted to classify CD271+ and CD271- ADSCs. Pathway analysis demonstrated CD271 expression on ADSCs was associated with the pathways related to stemness and cell differentiation. Indeed, we found that genes related to cell proliferation (PI3K, Cyclin D, and Cyclin D2) were up-regulated in CD271+ ADSCs. Additionally, we found the pericytic marker nestin which was significantly up-regulated in CD271+ ADSCs. Consistent with these findings, CD271+ ADSCs were more proliferative and capable for endothelial differentiation while CD271- ADSCs were not.

FACS and cell therapy experiments

Conclusion

These results suggest that CD271+ ADSCs possess long-term engraftment and angiogenic capacity due to their less-aged and more pericytic gene profile.

Acknowledgement/Funding

Japan Society for the Promotion of Science (JSPS) KAKENHI (Tokyo, Japan) Grant Number JP16H06828

P2590A liver-derived secretory protein, selenoprotein P causes pressure overload-induced cardiac hypertrophys

Background

Hepatokine selenoprotein P (SeP) contributes to insulin resistance and hyperglycemia in patients with type 2 diabetes. Inhibition of SeP protects the heart from ischemia reperfusion injury and serum levels of SeP are elevated in patients with heart failure with reduced ejection fraction.

Objective

We investigated the role of SeP in the regulation of cardiac remodeling in response to pressure overload.

Methods and results

To examine the role of SeP in cardiac remodeling, transverse aortic constriction (TAC) was subjected to SeP knockout (KO) and wild-type (WT) mice for 2 weeks. Hepatic expression of SeP in WT was significantly increased by TAC. LV weight/tibial length (TL) was significantly smaller in SeP KO mice than in WT mice (6.75±0.24 vs 8.33±0.32, p<0.01). Lung weight/TL was significantly smaller in SeP KO than in WT mice (10.46±0.44 vs 16.38±1.12, p<0.05). TAC-induced cardiac upregulation of the fetal type genes, including atrial and brain natriuretic factors, was significantly attenuated in SeP KO compared to WT. Furthermore, azan staining revealed that there was significantly less interstitial fibrosis in hearts after TAC in SeP KO than in WT mice. To determine whether hepatic overexpression of SeP affects TAC-induced cardiac hypertrophy, a hydrodynamic injection method was used to generate mice that overexpress SeP mRNA in the liver. Hepatic overexpression of SeP in SeP KO mice lead to a significant increase in LV weight/TL and Lung weight/TL after TAC compared to that in other SeP KO mice.

Conclusions

These results suggest that cardiac pressure overload induced hepatic expression of SeP and the absence of endogenous SeP attenuated cardiac hypertrophy, dysfunction and fibrosis in response to pressure overload in mice. SeP possibly plays a maladaptive role against progression of heart failure through the liver-heart axis.

Safety and efficacy of nivolumab in combination with S-1/capecitabine plus oxaliplatin in patients with previously untreated, unresectable, advanced, or recurrent gastric/gastroesophageal junction cancer: interim results of a randomized, phase II trial (ATTRACTION-4)

BACKGROUND

Nivolumab is approved as an option for third- or later-line treatment of advanced gastric/gastroesophageal junction (G/GEJ) cancer in several countries after ATTRACTION-2. To further improve the therapeutic efficacy of first-line therapy, exploration of a nivolumab-chemotherapy combination is warranted. In part 1 (phase II) of ATTRACTION-4, the safety and efficacy of nivolumab combined with S-1 plus oxaliplatin (SOX) or capecitabine plus oxaliplatin (CapeOX) as first-line therapy for unresectable advanced or recurrent human epidermal growth factor receptor 2 (HER2)-negative G/GEJ cancer were evaluated.

PATIENTS AND METHODS

Patients were randomized (1 : 1) to receive nivolumab (360 mg intravenously every 3 weeks) plus SOX (S-1, 40 mg/m2 orally twice daily for 14 days followed by 7 days off; oxaliplatin, 130 mg/m2 intravenously on day 1 every 3 weeks) or CapeOX (capecitabine, 1000 mg/m2 orally twice daily for 14 days followed by 7 days off; oxaliplatin, 130 mg/m2 intravenously on day 1 every 3 weeks) until disease progression, unacceptable toxicity, or consent withdrawal.

RESULTS

Of 40 randomized patients, 39 (nivolumab plus SOX, 21; nivolumab plus CapeOX, 18) and 38 (21 and 17, respectively) comprised the safety and efficacy populations, respectively. Most frequent (>10%) grade 3/4 treatment-related adverse events were neutropenia (14.3%) in the nivolumab plus SOX group, and neutropenia (16.7%), anemia, peripheral sensory neuropathy, decreased appetite, type 1 diabetes mellitus, and nausea (11.1% each) in the nivolumab plus CapeOX group. No treatment-related death occurred. Objective response rate was 57.1% (95% confidence interval 34.0-78.2) with nivolumab plus SOX and 76.5% (50.1-93.2) with nivolumab plus CapeOX. Median overall survival was not reached (NR) in both groups. Median progression-free survival was 9.7 months (5.8-NR) and 10.6 months (5.6-12.5), respectively.

CONCLUSION

Nivolumab combined with SOX/CapeOX was well tolerated and demonstrated encouraging efficacy for unresectable advanced or recurrent HER2-negative G/GEJ cancer. ATTRACTION-4 has proceeded to part 2 (phase III) to compare nivolumab plus SOX/CapeOX versus placebo plus SOX/CapeOX.

CLINICALTRIALS.GOV ID

NCT02746796.

Caste-specific microRNA expression in termites: insights into soldier differentiation

Eusocial insects have polyphenic caste systems in which each caste exhibits characteristic morphology and behaviour. In insects, caste systems arose independently in different lineages, such as Isoptera and Hymenoptera. Although partial molecular mechanisms for the development of eusociality in termites have been clarified by the functional analysis of genes and hormones, the contribution of microRNAs (miRNAs) to caste differentiation is unknown. To understand the role of miRNAs in termite caste polyphenism, we performed small RNA sequencing in a subterranean termite (Reticulitermes speratus) and identified the miRNAs that were specifically expressed in the soldier and worker castes. Of the 550 miRNAs annotated in the R. speratus genome, 74 were conserved in insects and 174 were conserved in other termite species. We found that eight miRNAs (mir-1, mir-125, mir-133, mir-2765, mir-87a and three termite-specific miRNAs) are differentially expressed (DE) in soldiers and workers of R. speratus. This differential expression was experimentally verified for five miRNAs by real-time quantitative PCR. Further, four of the eight DE miRNAs in soldier and worker termite castes were also differentially expressed in hymenopteran castes. The finding that Isoptera and Hymenoptera shared several DE miRNAs amongst castes suggests that these miRNAs evolved independently in these phylogenetically distinct lineages.

Biomarker analysis beyond angiogenesis: RAS/RAF mutation status, tumour sidedness, and second-line ramucirumab efficacy in patients with metastatic colorectal carcinoma from RAISE-a global phase III study

Background

: Second-line treatment with ramucirumab+FOLFIRI improved overall survival (OS) versus placebo+FOLFIRI for patients with metastatic colorectal carcinoma (CRC) [hazard ratio (HR)=0.84, 95% CI 0.73-0.98, P = 0.022]. Post hoc analyses of RAISE patient data examined the association of RAS/RAF mutation status and the anatomical location of the primary CRC tumour (left versus right) with efficacy parameters.

Patients and methods

Patient tumour tissue was classified as BRAF mutant, KRAS/NRAS (RAS) mutant, or RAS/BRAF wild-type. Left-CRC was defined as the splenic flexure, descending and sigmoid colon, and rectum; right-CRC included transverse, ascending colon, and cecum.

Results

RAS/RAF mutation status was available for 85% of patients (912/1072) and primary tumour location was known for 94.4% of patients (1012/1072). A favourable and comparable ramucirumab treatment effect was observed for patients with RAS mutations (OS HR = 0.86, 95% CI 0.71-1.04) and patients with RAS/BRAF wild-type tumours (OS HR = 0.86, 95% CI 0.64-1.14). Among the 41 patients with BRAF-mutated tumours, the ramucirumab benefit was more notable (OS HR = 0.54, 95% CI 0.25-1.13), although, as with the other genetic sub-group analyses, differences were not statistically significant. Progression-free survival (PFS) data followed the same trend. Treatment-by-mutation status interaction tests (OS P = 0.523, PFS P = 0.655) indicated that the ramucirumab benefit was not statistically different among the mutation sub-groups, although the small sample size of the BRAF group limited the analysis. Addition of ramucirumab to FOLFIRI improved left-CRC median OS by 2.5 month over placebo (HR = 0.81, 95% CI 0.68-0.97); median OS for ramucirumab-treated patients with right-CRC was 1.1 month over placebo (HR = 0.97, 95% CI 0.75-1.26). The treatment-by-sub-group interaction was not statistically significant for tumour sidedness (P = 0.276).

Conclusions

In the RAISE study, the addition of ramucirumab to FOLFIRI improved patient outcomes, regardless of RAS/RAF mutation status, and tumour sidedness. Ramucirumab treatment provided a numerically substantial benefit in BRAF-mutated tumours, although the P-values were not statistically significant.

ClinicalTrials.gov number

NCT01183780.