The impact of rare cancer and early-line treatments on the benefit of comprehensive genome profiling-based precision oncology

BACKGROUND

Comprehensive genome profiling (CGP) serves as a guide for suitable genomically matched therapies for patients with cancer. However, little is known about the impact of the timing and types of cancer on the therapeutic benefit of CGP.

MATERIALS AND METHODS

A single hospital-based pan-cancer prospective study (TOP-GEAR; UMIN000011141) was conducted to examine the benefit of CGP with respect to the timing and types of cancer. Patients with advanced solid tumors (>30 types) who either progressed with or without standard treatments were genotyped using a single CGP test. The subjects were followed up for a median duration of 590 days to examine therapeutic response, using progression-free survival (PFS), PFS ratio, and factors associated with therapeutic response.

RESULTS

Among the 507 patients, 62 (12.2%) received matched therapies with an overall response rate (ORR) of 32.3%. The PFS ratios (≥1.3) were observed in 46.3% (19/41) of the evaluated patients. The proportion of subjects receiving such therapies in the rare cancer cohort was lower than that in the non-rare cancer cohort (9.6% and 17.4%, respectively; P = 0.010). However, ORR of the rare cancer patients was higher than that in the non-rare cancer cohort (43.8% and 20.0%, respectively; P = 0.046). Moreover, ORR of matched therapies in the first or second line after receiving the CGP test was higher than that in the third or later lines (62.5% and 21.7%, respectively; P = 0.003). Rare cancer and early-line treatment were significantly and independently associated with ORR of matched therapies in multivariable analysis (P = 0.017 and 0.004, respectively).

CONCLUSION

Patients with rare cancer preferentially benefited from tumor mutation profiling by increasing the chances of therapeutic response to matched therapies. Early-line treatments after profiling increase the therapeutic benefit, irrespective of tumor types.

Serum/glucose starvation strikingly reduces heterogeneous nuclear ribonucleoprotein A1 protein and its target, cyclin D1

Our investigation to explore cellular alterations related to undernutrition in cancer cells revealed that the protein level of heterogenous nuclear ribonucleoprotein A1 (hnRNP A1) is drastically decreased by serum/glucose starvation. Its loss was reversible, serum/glucose starvation-specific and universal throughout cell types and species. The hnRNP A1 mRNA level and hnRNP A1 mRNA/protein stability were not altered under this condition. CCND1 mRNA, which we newly identified as the binding target of hnRNP A1, was decreased by serum/glucose starvation. Under similar conditions, CCND1 protein was reduced in vitro and in vivo, whereas hnRNP A1 mRNA level and CCND1 mRNA level revealed no correlation in most clinical samples. Functional analyses revealed that CCND1 mRNA stability is certainly dependent on hnRNP A1 protein level and that RNA recognition motif-1 (RRM1) in hnRNP A1 plays a central role in maintaining CCND1 mRNA stability and subsequent protein expression. The injection of RRM1-deleted hnRNP A1-expressing cancer cells in the mouse xenograft model did not form any tumours, and that of hnRNP A1-expressing cancer cells retained CCND1 expression at the lesion adjacent to necrosis with a slight increase in tumour volume. Furthermore, RRM1 deletion caused growth suppression with the induction of apoptosis and autophagy, whereas CCND1 restoration completely recovered it. Our results indicate that serum/glucose starvation triggers entire hnRNP A1 protein loss, and its loss may play a role in CCND1 mRNA destabilization and CCND1-mediated cellular event inhibition, i.e. growth promotion, apoptosis induction and autophagosome formation.

SV40 miR-S1 and Cellular miR-1266 Sequester Each Other from Their Targets, Enhancing Telomerase Activity and Viral Replication

Virus-encoded microRNAs (miRNAs) target viral and host mRNAs to repress protein production from viral and host genes, and regulate viral persistence, cell transformation, and evasion of the immune system. The present study demonstrated that simian virus 40 (SV40)-encoded miRNA miR-S1 targets a cellular miRNA miR-1266 to derepress their respective target proteins, namely, T antigens (Tags) and telomerase reverse transcriptase (TERT). An in silico search for cellular miRNAs to interact with viral miR-S1 yielded nine potential miRNAs, five of which, including miR-1266, were found to interact with miR-S1 in dual-luciferase tests employing reporter plasmids containing the miRNA sequences with miR-S1. Intracellular bindings of miR-1266 to miR-S1 were also verified by the pull-down assay. These miRNAs were recruited into the Ago2-associated RNA-induced silencing complex. Intracellular coexpression of miR-S1 with miR-1266 abrogated the downregulation of TERT and decrease in telomerase activity induced by miR-1266. These effects of miR-S1 were also observed in miR-1266-expressing A549 cells infected with SV40. Moreover, the infected cells contained more Tag, replicated more viral DNA, and released more viral particles than control A549 cells infected with SV40, indicating that miR-S1-induced Tag downregulation was antagonized by miR-1266. Collectively, the present results revealed an interplay of viral and cellular miRNAs to sequester each other from their respective targets. This is a novel mechanism for viruses to manipulate the expression of viral and cellular proteins, contributing to not only viral lytic and latent replication but also cell transformation observed in viral infectious diseases including oncogenesis.

SV40 microRNA miR-S1-3p Downregulates the Expression of T Antigens to Control Viral DNA Replication, and TNFα and IL-17F Expression

SV40-encoded microRNA (miRNA), miR-S1, downregulates the large and small T antigens (LTag and STag), which promote viral replication and cellular transformation, thereby presumably impairing LTag and STag functions essential for the viral life cycle. To explore the functional significance of miR-S1-mediated downregulation of LTag and STag as well as the functional roles of miR-S1, we evaluated viral DNA replication and proinflammatory cytokine induction in cells transfected with simian virus 40 (SV40) genome plasmid and its mutated form lacking miR-S1 expression. The SV40 genome encodes two mature miR-S1s, miR-S1-3p and miR-S1-5p, of which miR-S1-3p is the predominantly expressed form. MiR-S1-3p exerted strong repressive effects on a reporter containing full-length sequence complementarity, but only marginal effect on one harboring a sequence complementary to its seed sequence. Consistently, miR-S1-3p downregulated LTag and STag transcripts with complete sequence complementarity through miR-S1-3p-Ago2-mediated mRNA decay. Transfection of SV40 plasmid induced higher DNA replication and lower LTag and STag transcripts in most of the examined cells compared to that miR-S1-deficient SV40 plasmid. However, miR-S1 itself did not affect DNA replication without the downregulation of LTag transcripts. Both LTag and STag induced the expression of tumor necrosis factor α (TNFα) and interleukin (IL)-17F, which was slightly reduced by miR-S1 due to miR-S1-mediated downregulation of LTag and STag. Forced miR-S1 expression did not affect TNFα expression, but increased IL-17F expression. Overall, our findings suggest that miR-S1-3p is a latent modifier of LTag and STag functions, ensuring efficient viral replication and attenuating cytokine expression detrimental to the viral life cycle.

P37 Long-term outcomes of patients at risks for Fontan operation: role of temporary fenestration

Purpose

Whereas fenestration at Fontan operation was reported to be effective for smooth initiation to Fontan circulation, subsequently developed aortopulmonary collateral arteries under the presence of remaining hypoxia were a matter of concern.So as our institutional policy, it is closed as much and early as possible (temporary fenestration). This study aimed to reveal long-term outcomes for patients at riskswho underwent Fontan operation with temporary fenestration.

Methods

Of 107 patients undergoing Fontan operation from 1995 to 2004, 79 patients (73.8%) were free from any risks (NR group) and 28 patients (26.2%) had risks for Fontan operation (R group). Hypoplastic left heart syndrome, heterotaxy syndrome with obstructive total anomalous of pulmonary venous connection, and individual cases with high preoperative pulmonary artery pressure (PAP), systemic ventricular end diastolic pressure (SVEDP) or low ejection fraction (SVEF) were defined as a risk for Fontan completion.Age at Fontan operation was older in R group (6.6 vs 2.3years-old, p = 0.0004). Preoperative PAP (12.8 vs 11.3mmHg, p = 0.03) and SVEDP (8.8 vs 7.1mmHg, p = 0.02) were higher and SVEF (53.7 vs 60.0%, p = 0.002) was lower in R group. Pulmonary vascular resistance (PVR) was not different. Fenestration was created in all patients in R group, then it was closed at the mean duration of 2.9 years after Fontan operation.

Results

Freedom from death or protein-losing enteropathy rate at 5, 10, and 15 years after Fontan operation were 97, 96, and 93% in NR group and 96, 93, and 86% in R group (log-rank: p = 0.20). Fifty-one patients (64.6%) in NR group and 17 patients (60.7%) in R group underwent serial catheter examinations at 5, 10, and 15 years after Fontan operation and exercise capacity testing at 15 years after Fontan operation (Figure). In R group, arterial oxygen saturation was lower and PVR was higher even after close of fenestration (Figure). In addition, 12 patients (71%) in R group developed significant veno-venous collaterals, which were defined by more than 3mm in diameter of collateral veins or a condition where pulmonary veins were contrasted in venography. On the contrary, cardiac index (CI), SVEDP, and PAP were not different and no significant difference on peak oxygen uptake and anaerobic threshold were observed between in 2 groups. 

Conclusions

Although the mild cyanosis remained due to the development of veno-venous collaterals after the closure of temporary fenestration, CI, SVEDP and PAP well maintained in patients at risk for Fontan operation. These results might to lead acceptable life prognosis and freedom fromprotein-losing enteropathy rate for patients at risk for Fontan operation.

Abstract P37 Figure

Inhibition of EP2/EP4 prostanoid receptor-mediated signaling suppresses IGF-1-induced proliferation of pancreatic cancer BxPC-3 cells via upregulating γ-glutamyl cyclotransferase expression

Inhibition of prostaglandin E₂ signaling via EP2/EP4 prostanoid receptors suppresses Insulin-like growth factor (IGF)-1-induced proliferation of pancreatic cancer BxPC-3 cells. To better understand the mechanism of EP2/EP4 signaling for controlling cell proliferation, we performed metabolome analyses in BxPC-3 cells treated with IGF-1 alone or IGF-1 plus EP2/EP4 inhibitors. These analyses revealed increased g-aminobutyric acid and 5-oxoproline production following the addition of EP2/EP4 inhibitors to IGF-1-treated cells. The expression of a 5-oxoproline-catalyzing enzyme, γ-glutamylcyclotransferase (GGCT), was also upregulated by IGF-1 treatment and further enhanced by the addition of EP2/EP4 inhibitors. Knockdown of GGCT expression resulted in the loss of suppressive effects of EP2/EP4 inhibitors on IGF-1-induced BxPC-3 cell proliferation, whereas GGCT overexpression repressed the basal proliferation of BxPC-3 cells but did not affect the suppressive effects of EP2/EP4 inhibitors. To summarize, we propose a role for EP2/EP4 signaling in regulating IGF-1-induced cell proliferation, in which EP2/EP4 signaling represses IGF-1-induced GGCT expression, which mediates and whose amount controls a branch of IGF-1 signaling to promote cell proliferation via extracellular signal-regulated kinase phosphorylation.

Web survey-based selection of controls for epidemiological analyses of a multi-prefectural outbreak of enterohaemorrhagic Escherichia coli O157 in Japan associated with consumption of self-grilled beef hanging tender

An outbreak of enterohaemorrhagic Escherichia coli O157 occurred in multiple prefectures of Japan in November 2009. We conducted two case-control studies with trace-back and trace-forward investigations to determine the source. The case definition was met by 21 individuals; 14 (66.7%) were hospitalised, but no haemolytic uraemic syndrome, acute encephalopathy or deaths occurred. Median age was 23 (range 12-48) years and 14 cases were male (66.7%). No significant associations with food were found in a case-control study by local public health centres, but our matched case-control study using Internet surveys found that beef hanging tender (or hanger steak), derived from the diaphragm of the cattle, was significantly associated with illness (odds ratio = 15.77; 95% confidence interval, 2.00-124.11). Pulsed-field gel electrophoresis analysis of isolates from patients and the suspected food showed five different patterns: two in faecal and food samples, and another three in patient faecal samples only, although there were epidemiological links to the meat consumed at the restaurants. Trace-back investigation implicated a common food processing company from outside Japan. Examination of the logistics of the meat processing company suggested that contamination did not occur in Japan. We concluded that the source of the outbreak was imported hanging tender. This investigation revealed that Internet surveys could be useful for outbreak investigations.

Occlusal Support, Dysphagia, Malnutrition, and Activities of Daily Living in Aged Individuals Needing Long-Term Care: A Path Analysis

OBJECTIVES

This study aimed to examine the interrelationships among occlusal support, dysphagia, malnutrition, and activities of daily living in aged individuals needing long-term care.

DESIGN

Cross-sectional study and path analysis.

SETTING

Long-term health care facilities, acute care hospitals, and the community.

PARTICIPANTS

Three hundred and fifty-four individuals aged ≥ 65 years with dysphagia or potential dysphagia in need of long-term care.

MEASUREMENTS

The modified Eichner Index, Dysphagia Severity Scale, Mini Nutritional Assessment Short Form, and Barthel index.

RESULTS

The participants included 118 males and 236 females with a mean (standard deviation) age of 83 (8) years. A total of 216 participants had functional occlusal support with or without dentures. Of the total participants, 73 were within normal limits regarding the severity of dysphagia, 119 exhibited dysphagia without aspiration, and 162 exhibited dysphagia with aspiration. Only 34 had a normal nutritional status, while 166 participants were malnourished, and 154 were at risk of malnutrition. The median Barthel index score was 30. Path analysis indicated two important findings: occlusal support had a direct effect on dysphagia (standard coefficient = 0.33), and dysphagia was associated directly with malnutrition (standard coefficient = 0.50). Dysphagia and malnutrition were associated directly with impaired activities of daily living (standard coefficient = 0.57, 0.22).

CONCLUSION

In aged individuals needing long-term care, occlusal support is associated directly with dysphagia and indirectly with malnutrition and activities of daily living via dysphagia.

Increase of Galanin in Trigeminal Ganglion during Tooth Movement

It is known that nerve fibers containing neuropeptides such as galanin increase in the periodontal ligament during experimental tooth movement. However, the origin of galanin-containing nerve fibers in the periodontal ligament remains unclear. This study was conducted to examine our hypothesis that the increased galanin nerve fibers have a sensory neuronal origin, and that the peptide is associated with pain transmission and/or periodontal ligament remodeling during experimental tooth movement. In control rats, galanin-immunoreactive trigeminal ganglion cells were very rare and were observed predominantly in small ganglion cells. After 3 days of experimental tooth movement, galanin-immunoreactive trigeminal ganglion cells significantly increased, and the most marked increase was observed at 5 days after experimental tooth movement. Furthermore, their cell size spectrum also significantly changed after 3 and 5 days of movement: Medium-sized and large trigeminal ganglion cells began expressing, and continued to express, galanin until 14 days after experimental tooth movement. These findings suggest that the increase of galanin in the periodontal ligament during experimental tooth movement at least partially originates from trigeminal ganglion neurons and may play a role in pain transmission and/or periodontal remodeling.

Potent acid inhibition by vonoprazan in comparison with esomeprazole, with reference to CYP2C19 genotype

BACKGROUND

Acid inhibitory effects of proton pump inhibitors (PPIs) are influenced by CYP2C19 genotype. In contrast, the potent acid inhibition of vonoprazan is not influenced by CYP2C19 genotype.

AIM

To compare the acid inhibitory effects of vonoprazan and esomeprazole in relation to CYP2C19 genotype.

METHODS

Twenty-eight healthy Japanese volunteers [7 CYP2C19 poor metabolisers (PMs), 11 intermediate metabolisers (IMs) and 10 rapid metabolisers (RMs)] received four different regimens in a randomised crossover manner: (i) vonoprazan 20 mg twice daily (b.d.), (ii) vonoprazan 20 mg daily, (iii) esomeprazole 20 mg b.d. and (iv) esomeprazole 20 mg daily. The timing of each dosing was 1 h before a meal. Twenty-four-hour intragastric pH monitoring was performed on day 7 on each regimen.

RESULTS

In the overall genotype group, pH ≥4 holding time ratios (pH 4 HTRs) with vonoprazan b.d., vonoprazan daily, esomeprazole b.d. and esomeprazole daily were 100%, 95%, 91%, and 68% respectively. pH 5 HTRs were 99%, 91%, 84% and 54% respectively. Vonoprazan b.d. potently suppressed acid for 24 h, and was significantly superior to other regimens irrespective of CYP2C19 genotype. Vonoprazan daily was equivalent to esomeprazole b.d. in IMs and PMs, but superior in RMs. CYP2C19 genotype-dependent differences were observed in esomeprazole daily but not in vonoprazan b.d. or daily.

CONCLUSION

Vonoprazan 20 mg b.d. inhibits acid irrespective of CYP2C19 genotype, more potently than esomeprazole 20 mg b.d., pH 4 and 5 holding time ratios reached 100% and 99%, respectively.

A20 targets caspase-8 and FADD to protect HTLV-I-infected cells

Adult T-cell leukemia (ATL) arises from a human T-cell leukemia virus type I (HTLV-I)-infected cell and has few therapeutic options. Here, we have uncovered a previously unrecognized role for a ubiquitin-editing enzyme A20 in the survival of HTLV-I-infected cells. Unlike in lymphomas of the B-cell lineage, A20 is abundantly expressed in primary ATL cells without notable mutations. Depletion of A20 in HTLV-I-infected cells resulted in caspase activation, cell death induction and impaired tumorigenicity in mouse xenograft models. Mechanistically, A20 stably interacts with caspase-8 and Fas-associated via death domain (FADD) in HTLV-I-infected cells. Mutational studies revealed that A20 supports the growth of HTLV-I-infected cells independent of its catalytic functions and that the zinc-finger domains are required for the interaction with and regulation of caspases. These results indicate a pivotal role for A20 in the survival of HTLV-I-infected cells and implicate A20 as a potential therapeutic target in ATL.

High Helicobacter pylori cure rate with sitafloxacin-based triple therapy

BACKGROUND

Bacterial resistance of Helicobacter pylori to antibiotics is increasing and it often leads to failure of antibiotic treatment. A new sitafloxacin-based triple therapy was developed to counter this situation; the fluoroquinolone sitafloxacin has a low minimum inhibitory concentration for H. pylori.

AIM

To investigate the efficacy in Japanese patients of sitafloxacin-based triple therapy and document its efficacy in relation to anti-microbial susceptibility.

METHODS

We investigated the efficacy of a 1-week sitafloxicin-based regimen of rabeprazole 10 mg four times daily (q.d.s.), metronidazole 250 mg twice daily (b.d.) and sitafloxacin 100 mg b.d. in 180 H. pylori-positive Japanese patients (first-line treatment: n = 45, second-line; n = 41, third-line: n = 94). At 8 weeks, patients were given the (13) C-urea breath test to assess eradication status.

RESULTS

Eradication rate was 92.2% [95% confidence interval (CI): 87.3-95.7%, 166/180] in intention-to-treat analysis. Although the eradication rate was higher in patients treated with first-line therapy [45/45 (100%, 95% CI: 83.4-100%)] than in those with second- [38/41 (92.7%, 80.1-98.5%)] or third-line therapy [83/94 (88.3%, 80.0-94.0%)], no significant differences were noted with respect to the number of previous therapy attempts (P = 0.054). Eradication rates in patients infected with sensitive- and resistant strains to metronidazole were 96.6% (28/29) and 96.3% (77/80) (P = 0.941), respectively, while rates were 98.4% (60/61) in sitafloxacin-sensitive and 50.0% (1/2) in sitafloxacin resistant strains (P < 0.001).

CONCLUSION

Sitofloxacin-based triple therapy with metronidazole b.d. and rabeprazole q.d.s. achieved an eradication rate exceeding 88%, irrespective of eradication history, CYP2C19 genotype, or metronidazole resistance status.

Twice-daily dosing of esomeprazole effectively inhibits acid secretion in CYP2C19 rapid metabolisers compared with twice-daily omeprazole, rabeprazole or lansoprazole

BACKGROUND

Twice-daily dosing of proton pump inhibitors (PPIs) is used to treat Helicobacter pylori or acid-related diseases, such as gastro-oesophageal reflux disease (GERD) refractory to standard dose of a PPI. Genetic polymorphisms of CYP2C19 are involved to different extents in the metabolism of four kinds of PPIs (omeprazole, lansoprazole, rabeprazole and esomeprazole) available in Japan.

AIM

To compare acid-inhibitory effects of the four PPIs dosed twice daily in relation to CYP2C19 genotype.

METHODS

We performed 24-h pH monitoring studies on Day 7 of PPI treatment for 40 Japanese H. pylori-negative volunteers [15 CYP2C19 rapid metabolisers (RMs), 15 intermediate metabolisers (IMs) and 10 poor metabolisers (PMs)] using a randomised four-way crossover design: omeprazole 20 mg, esomeprazole 20 mg, lansoprazole 30 mg and rabeprazole 10 mg twice daily.

RESULTS

Although median pH values with esomeprazole, omeprazole, lansoprazole and rabeprazole were 5.7 (3.5-7.2), 5.5 (2.4-7.2), 5.5 (3.7-7.3) and 5.2 (2.5-7.3), respectively (no statistically significant differences), CYP2C19 genotype-dependent differences were smaller for esomeprazole and rabeprazole compared with values for omeprazole and lansoprazole. In CYP2C19 RMs, the median pH with esomeprazole [5.4 (3.5-6.8)] was significantly higher than those with omeprazole [5.0 (2.4-5.9), P = 0.018], lansoprazole [4.7 (3.7-5.5), P = 0.017] or rabeprazole [4.8 (2.5-6.4), P = 0.002]. In IMs and PMs, the median pH was >5.0 independent of the PPI.

CONCLUSIONS

In intermediate and rapid metabolisers of CYP2C19, PPIs dosed twice daily could attain sufficient acid suppression, while in CYP2C19 RMs, esomeprazole 20 mg twice daily caused the strongest inhibition of the four PPIs. Therefore, esomeprazole may be effective in Japanese population when dosed twice daily.