Cooperative recruitment of RDR6 by SGS3 and SDE5 during small interfering RNA amplification in Arabidopsis.

Small interfering RNAs (siRNAs) are often amplified from transcripts cleaved by RNA-induced silencing complexes (RISCs) containing a small RNA (sRNA) and an Argonaute protein. Amplified siRNAs, termed secondary siRNAs, are important for reinforcement of target repression. In plants, target cleavage by RISCs containing 22-nucleotide (nt) sRNA and Argonaute 1 (AGO1) triggers siRNA amplification. In this pathway, the cleavage fragment is converted into double-stranded RNA (dsRNA) by RNA-dependent RNA polymerase 6 (RDR6), and the dsRNA is processed into siRNAs by Dicer-like proteins. Because nonspecific RDR6 recruitment causes nontarget siRNA production, it is critical that RDR6 is specifically recruited to the target RNA that serves as a template for dsRNA formation. Previous studies showed that Suppressor of Gene Silencing 3 (SGS3) binds and stabilizes 22-nt sRNA-containing AGO1 RISCs associated with cleaved target, but how RDR6 is recruited to targets cleaved by 22-nt sRNA-containing AGO1 RISCs remains unknown. Here, using cell-free extracts prepared from suspension-cultured Arabidopsis thaliana cells, we established an in vitro system for secondary siRNA production in which 22-nt siRNA-containing AGO1-RISCs but not 21-nt siRNA-containing AGO1-RISCs induce secondary siRNA production. In this system, addition of recombinant Silencing Defective 5 (SDE5) protein remarkably enhances secondary siRNA production. We show that RDR6 is recruited to a cleavage fragment by 22-nt siRNA-containing AGO1-RISCs in coordination with SGS3 and SDE5. The SGS3-SDE5-RDR6 multicomponent recognition system and the poly(A) tail inhibition may contribute to securing specificity of siRNA amplification.

Tumor Targeting of 211At-Labeled Antibody under Sodium Ascorbate Protection against Radiolysis.

Astatine-211 (211At) is an alpha emitter applicable to radioimmunotherapy (RIT), a cancer treatment that utilizes radioactive antibodies to target tumors. In the preparation of 211At-labeled monoclonal antibodies (211At-mAbs), the possibility of radionuclide-induced antibody denaturation (radiolysis) is of concern. Our previous study showed that this 211At-induced radiochemical reaction disrupts the cellular binding activity of an astatinated mAb, resulting in attenuation of in vivo antitumor effects, whereas sodium ascorbate (SA), a free radical scavenger, prevents antibody denaturation, contributing to the maintenance of binding and antitumor activity. However, the influence of antibody denaturation on the pharmacokinetics of 211At-mAbs relating to tumor accumulation, blood circulation time, and distribution to normal organs remains unclear. In this study, we use a radioactive anti-human epidermal growth factor receptor 2 (anti-HER2) mAb to demonstrate that an 211At-induced radiochemical reaction disrupts active targeting via an antigen-antibody interaction, whereas SA helps to maintain targeting. In contrast, there was no difference in blood circulation time as well as distribution to normal organs between the stabilized and denatured immunoconjugates, indicating that antibody denaturation may not affect tumor accumulation via passive targeting based on the enhanced permeability and retention effect. In a high-HER2-expressing xenograft model treated with 1 MBq of 211At-anti-HER2 mAbs, SA-dependent maintenance of active targeting contributed to a significantly better response. In treatment with 0.5 or 0.2 MBq, the stabilized radioactive mAb significantly reduced tumor growth compared to the denatured immunoconjugate. Additionally, through a comparison between a stabilized 211At-anti-HER2 mAb and radioactive nontargeted control mAb, we demonstrate that active targeting significantly enhances tumor accumulation of radioactivity and in vivo antitumor effect. In RIT with 211At, active targeting contributes to efficient tumor accumulation of radioactivity, resulting in a potent antitumor effect. SA-dependent protection that successfully maintains tumor targeting will facilitate the clinical application of alpha-RIT.

Discovery of a big void in Khufu's Pyramid by observation of cosmic-ray muons.

The Great Pyramid, or Khufu's Pyramid, was built on the Giza plateau in Egypt during the fourth dynasty by the pharaoh Khufu (Cheops), who reigned from 2509 bc to 2483 bc. Despite being one of the oldest and largest monuments on Earth, there is no consensus about how it was built. To understand its internal structure better, we imaged the pyramid using muons, which are by-products of cosmic rays that are only partially absorbed by stone. The resulting cosmic-ray muon radiography allows us to visualize the known and any unknown voids in the pyramid in a non-invasive way. Here we report the discovery of a large void (with a cross-section similar to that of the Grand Gallery and a minimum length of 30 metres) situated above the Grand Gallery. This constitutes the first major inner structure found in the Great Pyramid since the nineteenth century. The void, named ScanPyramids' Big Void, was first observed with nuclear emulsion films installed in the Queen's chamber, then confirmed with scintillator hodoscopes set up in the same chamber and finally re-confirmed with gas detectors outside the pyramid. This large void has therefore been detected with high confidence by three different muon detection technologies and three independent analyses. These results constitute a breakthrough for the understanding of the internal structure of Khufu's Pyramid. Although there is currently no information about the intended purpose of this void, these findings show how modern particle physics can shed new light on the world's archaeological heritage.

New Cluster Analysis Method for Quantitative Dynamic Contrast-Enhanced MRI Assessing Tumor Heterogeneity Induced by a Tumor-Microenvironmental Ameliorator (E7130) Treatment to a Breast Cancer Mouse Model.

BACKGROUND: Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can provide insight into tumor perfusion. However, a method that can quantitatively measure the intra-tumor distribution of tumor voxel clusters with a distinct range of Ktrans and ve values remains insufficiently explored. HYPOTHESIS: Two-dimensional cluster analysis may quantify the distribution of a tumor voxel subregion with a distinct range of Ktrans and ve values in human breast cancer xenografts. STUDY TYPE: Prospective longitudinal study. ANIMAL MODEL: Twenty-two female athymic nude mice with MCF-7 xenograft, treated with E7130, a tumor-microenvironmental ameliorator, or saline. FIELD STRENGTH/SEQUENCE: 9.4 Tesla, turbo rapid acquisition with relaxation enhancement, and spoiled gradient-echo sequences. ASSESSMENT: We performed two-dimensional k-means clustering to identify tumor voxel clusters with a distinct range of Ktrans and ve values on Days 0, 2, and 5 after treatment, calculated the ratio of the number of tumor voxels in each cluster to the total number of tumor voxels, and measured the normalized distances defined as the ratio of the distance between each tumor voxel and the nearest tumor margin to a tumor radius. STATISTICAL TESTS: Unpaired t-tests, Dunnett's multiple comparison tests, and Chi-squared test were used. RESULTS: The largest and second largest clusters constituted 44.4% and 27.5% of all tumor voxels with cluster centroid values of Ktrans at 0.040 min-1 and 0.116 min-1 , and ve at 0.131 and 0.201, respectively. At baseline (Day 0), the average normalized distances for the largest and second largest clusters were 0.33 and 0.24, respectively. E7130-treated group showed the normalized distance of the initial largest cluster decreasing to 0.25, while that of the second largest cluster increasing to 0.31. Saline-treated group showed no change. DATA CONCLUSION: A two-dimensional cluster analysis might quantify the spatial distribution of a tumor subregion with a distinct range of Ktrans and ve values. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 1.

Real-world clinical outcomes in Japanese patients with locally advanced squamous cell carcinoma of the head and neck treated with radiotherapy plus cetuximab: a prospective observational study (JROSG12-2).

BACKGROUND: Radiotherapy plus cetuximab (bioradiotherapy: BRT) is a standard option in the treatment of locally advanced squamous cell carcinoma of the head and neck (LA-SCCHN). Published data on its safety and efficacy in real-world settings is limited. Here, we conducted a prospective multi-institutional observational study to evaluate clinical outcomes of BRT in patients with LA-SCCHN. METHODS: We analyzed real-world data of all patients who underwent BRT from 2013 to 2016. The primary endpoint was 1-year progression-free survival (PFS). Secondary endpoints were 1-year locoregional PFS (LPFS), treatment completion rate (TCR), and adverse events (AEs). RESULTS: A total of 171 patients with a minimum 1-year follow-up were analyzed. Median age was 67 (36-85) years, and 37 patients (21.6%) were aged 75 years or older. 1-year PFS and LPFS were 51.5 and 56.1%, respectively. N stage (p = 0.049) was significantly associated with PFS. TCR was 77.2%. Cetuximab was definitively discontinued in 30 patients (17.5%), in 15 cases due to severe mucositis. N stage, T stage, and comorbidity were significantly associated with TCR. Major AEs of grade 3 or higher were pharyngeal mucositis (48.5%), radiation dermatitis (45.6%), and oral mucositis (40.4%). Pneumonitis was observed in 12 patients (7.0%); 6 cases (3.5%) were grades 3-4 and 2 (1.2%) were grade 5. CONCLUSION: As a result of the large number of elderly patients in clinical practice,　toxicity reduced TCR. BRT-induced pneumonitis, which is sometimes fatal, was found to be more frequent than with chemotherapy plus cetuximab.

Radioimmunotherapy with an 211 At-labeled anti-tissue factor antibody protected by sodium ascorbate.

Tissue factor (TF), the trigger protein of the extrinsic blood coagulation cascade, is abundantly expressed in various cancers including gastric cancer. Anti-TF monoclonal antibodies (mAbs) capable of targeting cancers have been successfully applied to armed antibodies such as antibody-drug conjugates (ADCs) and molecular imaging probes. We prepared an anti-TF mAb, clone 1084, labeled with astatine-211 (211 At), as a promising alpha emitter for cancer treatment. Alpha particles are characterized by high linear energy transfer and a range of 50-100 µm in tissue. Therefore, selective and efficient tumor accumulation of alpha emitters results in potent antitumor activities against cancer cells with minor effects on normal cells adjacent to the tumor. Although the 211 At-conjugated clone 1084 (211 At-anti-TF mAb) was disrupted by an 211 At-induced radiochemical reaction, we demonstrated that astatinated anti-TF mAbs eluted in 0.6% or 1.2% sodium ascorbate (SA) solution were protected from antibody denaturation, which contributed to the maintenance of cellular binding activities and cytocidal effects of this immunoconjugate. Although body weight loss was observed in mice administered a 1.2% SA solution, the loss was transient and the radioprotectant seemed to be tolerable in vivo. In a high TF-expressing gastric cancer xenograft model, 211 At-anti-TF mAb in 1.2% SA exerted a significantly greater antitumor effect than nonprotected 211 At-anti-TF mAb. Moreover, the antitumor activities of the protected immunoconjugate in gastric cancer xenograft models were dependent on the level of TF in cancer cells. These findings suggest the clinical availability of the radioprotectant and applicability of clone 1084 to 211 At-radioimmunotherapy.

A management of neutropenia using granulocyte colony stimulating factor support for chemotherapy consisted of docetaxel, cisplatin and 5-fluorouracil in patients with oesophageal squamous cell carcinoma.

BACKGROUND: An exploratory study was designed to evaluate the efficacy of granulocyte colony stimulating factor support for chemotherapy consisting of docetaxel, cisplatin and 5-fluorouracil chemotherapy in patients with oesophageal cancer. METHODS: The inclusion criteria were as follows: (1) oesophageal squamous cell carcinoma, (2) a schedule to receive three courses of induction chemotherapy (docetaxel 75 mg/m2 day 1, cisplatin 75 mg/m2 day 1, 5-fluorouracil 750 mg/m2 days 1-5, every 3 weeks), (3) stage IB-III, (4) 20-75 years old, (5) 0-1 performance status, (6) preserved organ functions and (7) written informed consent. The endpoints were to evaluate the efficacy of granulocyte colony stimulating factor support including secondary prophylactic usage for docetaxel, cisplatin and 5-fluorouracil chemotherapy. Patients who previously had 'febrile neutropenia', or 'Grade 3 or 4 infection accompanied by grade 3 or 4 neutropenia' prophylactically received granulocyte colony stimulating factor support from day 7. RESULTS: A total of 91 patients were included in the analysis. Granulocyte colony stimulating factor support was given to 81.3%. The incidence of grade 4 neutropenia and febrile neutropenia were 81.3 and 32.9%, respectively. The dose of anticancer agents was reduced in 48.4%. There were no treatment-related deaths. The relative dose intensity of docetaxel, cisplatin and 5-fluorouracil were 92.7 ± 9.8%, 86.0 ± 15.6% and 91.8 ± 10.0%, respectively. In the secondary prophylactic granulocyte colony stimulating factor support group, the neutrophil count significantly increased between day 7 and day 13 as compared with the non-prophylactic granulocyte colony stimulating factor support group (P < 0.05 for each day). CONCLUSIONS: Granulocyte colony stimulating factor support including secondary prophylactic usage may be feasible for maintaining the intensity of docetaxel, cisplatin and 5-fluorouracil chemotherapy in patients with oesophageal cancer.

Phase II study of cetuximab plus S-1/cisplatin therapy in Japanese patients with advanced gastric cancer.

OBJECTIVE: We evaluated the efficacy and safety of first-line S-1 plus cisplatin in combination with cetuximab for Japanese patients with advanced gastric cancer, including gastroesophageal junction adenocarcinoma. METHODS: This open-label, single arm, multicenter, phase 2 trial was conducted to assess first-line cetuximab plus S-1 plus cisplatin for advanced gastric cancer. A total of 40 patients from 10 centers were enrolled. Cetuximab was administered weekly, with the initial infusion at 400 mg/m2 and then 250 mg/m2 each subsequent week. S-1 plus cisplatin chemotherapy was concomitantly conducted in a 5-week cycle: S-1 (40-60 mg, adjusted for body surface area) was given twice daily for 3 consecutive weeks, followed by a 2-week rest period, and cisplatin (60 mg/m2) was given on day 8 of each cycle for a maximum of 8 cycles. Treatment continued until the occurrence of radiographically confirmed progressive disease, unacceptable toxicity or withdrawal of consent. The primary endpoint was the best overall response. Secondary endpoints included progression-free survival and safety. RESULTS: A total of 40 patients were evaluable. One patient (2.5%) had a complete response; 15 patients (37.5%) had a partial response. The observed overall response rate according to the independent review committee was 40.0% (95% confidence interval, 24.9-56.7; P = 0.7043 [one-sided null hypothesis: overall response rate ≤ 43%]); median PFS was 5.6 months (95% confidence intervals, 4.2-8.3). No adverse events leading to death were reported during the study, and no specific safety concerns were observed. CONCLUSIONS: Overall, the addition of cetuximab to S-1 plus cisplatin was well tolerated in patients with advanced gastric cancer but provided no additional clinical benefit in this study. ClinicalTrials.gov identifier: NCT01388790.

Real-world clinical outcomes and prognostic factors in Japanese patients with recurrent or metastatic squamous cell carcinoma of head and neck treated with chemotherapy plus cetuximab: a prospective observation study (JROSG12-2).

BACKGROUND: The aims of this study are to evaluate the efficacy and safety of first-line treatment with chemotherapy plus cetuximab in real-world patients with recurrent or metastatic squamous cell carcinoma of the head and neck (RM-SCCHN) and to identify prognostic factors for overall survival (OS). METHODS: This is a prospective observation study involving 20 oncology institutions in Japan. Patients with RM-SCCHN treated with a first-line therapy consisting of cetuximab plus any chemotherapy regimen between December 2013 and February 2017 were enrolled. The primary objective of the study was 1-year OS. Secondary objectives included response rate and adverse events. RESULTS: Of 120 patients recruited, 114 patients were analyzed. Median age was 64 years. Cetuximab in combination with platinum plus 5-FU (EXTREME regimen) was chosen in 86 patients (75.4%). The median OS was 12.4 months. A point estimate of the 1-year survival rate was 51.1%. Overall response rate was 26.3%. Grade 3 or worse adverse events included neutropenia (22.8%), hypokalemia (9.6%), acneiform rash (7.0%), pneumonitis (1.8%), and infusion-related reaction (0.9%). On multivariate analysis, regional lymph node metastasis, absence of intervention by dermatologists, lack of response to therapy, skin metastasis, and non-EXTREME regimen were identified as independent unfavorable prognostic factors for OS. CONCLUSION: The combination of cetuximab plus chemotherapy was tolerable and efficacious in patients with RM-SCCHN in a real-world setting. Clinical outcomes and prognostic factors extracted from this study provide a reference of the current clinical practice as well as for the future development of novel therapy in RM-SCCHN.

Optimizing antiemetic treatment for chemotherapy-induced nausea and vomiting in Japan: Update summary of the 2015 Japan Society of Clinical Oncology Clinical Practice Guidelines for Antiemesis.

Patients with cancer should appropriately receive antiemetic therapies against chemotherapy-induced nausea and vomiting (CINV). Antiemetic guidelines play an important role in managing CINV. Accordingly, the first Japanese antiemetic guideline published in 2010 by the Japan Society of Clinical Oncology (JSCO) has considerably aided Japanese medical staff in providing antiemetic therapies across chemotherapy clinics. With the yearly advancements in antiemetic therapies, the Japanese antiemetic guidelines require revisions according to published evidence regarding antiemetic management worldwide. A revised version of the first antiemetic guideline that considered several upcoming evidences had been published online in 2014 (version 1.2), in which several updated descriptions were included. The 2015 JSCO clinical practice guideline for antiemesis (version 2.0) (in Japanese) has addressed clinical antiemetic concerns and includes four major revisions regarding (1) changes in emetogenic risk categorization for anti-cancer agents, (2) olanzapine usage as an antiemetic drug, (3) the steroid-sparing method, and (4) adverse drug reactions of antiemetic agents. We herein present an English update summary for the 2015 JSCO clinical practice guideline for antiemesis (version 2.0).

[Superior Mesenteric Artery Bypass Grafting from the Ascending Aorta Using a Saphenous Vein Graft for Treatment of Acute Aortic Dissection with Abdominal Malperfusion:Report of a Case].

A 50-year-old man presented with abdominal pain and numbness in the right leg. He was diagnosed with type A acute aortic dissection with malperfusion of the superior mesenteric artery(SMA) and the right external iliac artery. Before median sternotomy, we made median celiotomy and anastomosed a saphenous vein graft to SMA. After cardio-pulmonary bypass was instituted, perfusion to the saphenous vein graft was started. After the central repair, we selected the vascular graft of the ascending aorta as the inflow of SMA bypass because leading the vein graft to the external iliac artery was difficult due to obesity and intestinal edema. The graft flow was favorable with 100 ml/minute. He was discharged on postoperative day 56 without any abdominal complications. Some reports suggested that early reperfusion improved the outcomes of surgery for acute aortic dissection with mesenteric ischemia. The ascending aorta may be a viable alternative as an inflow of SMA bypass when the iliac artery is inappropriate.

Treatment margins in radiotherapy for liver tumors visualized as T2*-hypointense areas on SPIO-enhanced MRI at 9.4 T.

OBJECTIVE: To investigate whether a SPIO-labeling technique could enable MR visualization of the treatment margin after X-irradiation at a single dose of 30 Gy. MATERIALS AND METHODS: Fifteen rats bearing N1-S1 hepatoma in either the left (group 1) or right (group 2) liver lobe were examined. Four hours after systemic SPIO administration, the left lobe was selectively irradiated at 30 Gy. Liver T2* maps were acquired 7 days later using a 9.4 T scanner. The livers were excised and examined histologically. RESULTS: The irradiated area showed T2*-weighted hypointensity with significantly shorter T2* values than those in the non-irradiated area (p < 0.001). Tumors in group 1 completely disappeared, whereas tumors in group 2 had grown outside the T2*-weighted hypointensity by up to ~ 2.3 times that at baseline. Group 1 showed significantly higher probability of tumor regression than group 2 (p = 0.048). Histologically, iron deposition was heavier in irradiated areas than in non-irradiated areas. DISCUSSION: Even at a single dose of 30 Gy, which is a slightly higher dose than can be used clinically in stereotactic body radiotherapy, MR visualization of the treatment margin was achieved, because tumors showed significant growth outside the T2*-hypointense areas. In contrast, tumors disappeared inside the T2*-hypointense areas.

[Assessment of Efficacy and Adverse Effects of Trastuzumab Biosimilar in Gastric Cancer].

The postmarketing assessment of biosimilars is important because posttranslational modification by glycosylation is altered by the manufacturing process. A retrospective study of 15 patients with gastric cancer receiving a combination anticancer therapy with trastuzumab was performed. The most common concurrent regimen was the S-1 and oxaliplatin combination; efficacy and adverse events were assessed in this group. There was no statistically significant difference in progression-free survival between patients receiving the reference formulation and patients receiving its biosimilar. The adverse events detected were similar in both groups. In the 6 patients who switched from the reference trastuzumab to its biosimilar, adverse events did not differ before and after the switch. This small-scale retrospective study found no differences in efficacy or adverse events between the reference trastuzumab and its biosimilar.

Exploration of potential prognostic biomarkers in aflibercept plus FOLFIRI in Japanese patients with metastatic colorectal cancer.

Aflibercept plus 5-fluorouracil/levofolinate/irinotecan (FOLFIRI) is a second-line treatment for metastatic colorectal cancer. This ancillary exploratory analysis of data in Japanese people was aimed at exploring the relationship between a set of potential prognostic biomarkers and efficacy endpoints following aflibercept plus FOLFIRI therapy. Sixty-two patients with metastatic colorectal cancer received aflibercept (4 mg/kg) plus FOLFIRI every 2 weeks. Seventy-eight potential protein biomarkers were chosen for analysis based on their roles in angiogenesis, tumor progression, and tumor-stroma interaction. Plasma levels of biomarkers at baseline and at pre-dose 3 (day 1 of treatment cycle 3) were measured in all patients by ELISA. Relationships between these levels and efficacy endpoints were assessed. Ten potential biomarkers had a ±30% change from baseline to pre-dose 3 (adjusted P < .001), with the greatest changes occurring in placental growth factor (median: +4716%) and vascular endothelial growth factor receptor 1 (+2171%). Baseline levels of eight potential biomarkers correlated with overall survival in a univariate Cox regression analysis: extracellular newly identified receptor for advanced glycation end-products binding protein, insulin-like growth factor-binding protein 1, interleukin-8, kallikrein 5, pulmonary surfactant-associated protein D, tissue inhibitor of metalloproteinases 1, tenascin-C, and tumor necrosis factor receptor 2. None correlated with progression-free survival or maximum tumor shrinkage. Pre-dose 3 levels did not correlate with any efficacy endpoints. Preliminary data show that these eight biomarkers could be associated with overall survival. ClinicalTrials.gov identifier: NCT01882868.

Impact of UGT1A1 genetic polymorphism on toxicity in unresectable pancreatic cancer patients undergoing FOLFIRINOX.

Studies have indicated an association between UDP-glucuronosyltransferase-1A1 (UGT1A1) genetic polymorphisms and irinotecan-induced toxicity. We undertook this study to investigate the association between UGT1A1 genetic polymorphisms and toxicity in patients treated with the FOLFIRINOX (comprising oxaliplatin, irinotecan, fluorouracil, and leucovorin) chemotherapy regimen in the JASPAC 06 study. Patients screened for UGT1A1*6 and UGT1A1*28, and treated with either the original FOLFIRINOX (oxaliplatin 85 mg/m2 , irinotecan 180 mg/m2 , leucovorin 200 mg/m2 , bolus 5-fluorouracil [5-FU] 400 mg/m2 , and continuous 5-FU 2400 mg/m2 ) or a modified FOLFIRINOX (oxaliplatin 85 mg/m2 , irinotecan 150 mg/m2 , leucovorin 200 mg/m2 , and continuous 5-FU 2400 mg/m2 ) as first-line chemotherapy were included. Of 199 patients eligible for this analysis, 79 patients were treated with the original FOLFIRINOX regimen and 120 patients were treated with the modified FOLFIRINOX regimen. In the original FOLFIRINOX group, 54 were UGT1A1 WT, and 25 were UGT1A1 heterozygous type (-/*6, 12 patients; -/*28, 13 patients). In the modified FOLFIRINOX group, 64 were UGT1A1 WT and 56 were UGT1A1 heterozygous type (-/*6, 33 patients; -/*28, 23 patients). In the original FOLFIRINOX group, the incidence of diarrhea was significantly higher among patients with UGT1A1 heterozygous type than among those with UGT1A1 WT and the incidence of leukopenia and diarrhea was significantly higher among patients with UGT1A1 -/*6 than among those with UGT1A1 -/*28. Patients with UGT1A1 heterozygous type, especially those with UGT1A1 -/*6, tended to show a higher incidence rate of severe adverse events, but this was not statistically significant. However, for patients who received the modified FOLFIRINOX, there was no difference in the frequency of adverse events due to UGT1A1 status. In conclusion, patients with heterozygous UGT1A1 polymorphisms treated with the original FOLFIRINOX regimen experienced severe toxicity more frequently than patients with WT UGT1A1.

Phase II trial of aflibercept with FOLFIRI as a second-line treatment for Japanese patients with metastatic colorectal cancer.

Aflibercept targets vascular endothelial growth factor. The present study involved assessing the efficacy, safety and pharmacokinetics of aflibercept plus 5-fluorouracil/levofolinate/irinotecan (FOLFIRI) as a second-line treatment for metastatic colorectal cancer (mCRC) in Japanese patients. Aflibercept (4 mg/kg) plus FOLFIRI was administered every 2 weeks in 62 patients with mCRC until disease progression, unacceptable toxicity or patient withdrawal. Tumors were imaged every 6 weeks. The primary endpoint was objective response rate (ORR); secondary endpoints were progression-free survival, overall survival, safety, and pharmacokinetics of aflibercept, irinotecan and 5-fluorouracil. A total of 60 patients were evaluated for ORR; 50 had received prior bevacizumab. The ORR was 8.3% (95% confidence interval [CI]: 1.3%-15.3%), and the disease control rate (DCR) was 80.0% (69.9%-90.1%). The median progression-free survival was 5.42 months (4.14-6.70 months) and the median overall survival was 15.59 months (11.20-19.81 months). No treatment-related deaths were observed, and no significant drug-drug interactions were found. The most common treatment-emergent adverse events were neutropenia and decreased appetite. Free aflibercept had a mean maximum concentration (coefficient of variation) of 73.2 µg/mL (15%), clearance of 0.805 L/d (22%) and volume of distribution of 6.2 L (18%); aflibercept bound with vascular endothelial growth factor had a clearance of 0.162 L/d (9%) (N = 62). Aflibercept did not significantly affect the pharmacokinetics of irinotecan or 5-fluorouracil: The clearance was 11.1 L/h/m2 (28%) for irinotecan and, at steady state, 72.6 L/h/m2 (56%) for 5-fluorouracil (N = 10). Adding aflibercept to FOLFIRI was shown to be beneficial and well-tolerated in Japanese patients with mCRC. ClinicalTrials.gov Identifier: NCT01882868.

Sex differences in the safety of S-1 plus oxaliplatin and S-1 plus cisplatin for patients with metastatic gastric cancer.

Previous studies have shown sex-related differences in the incidence of adverse events following treatment with fluoropyrimidines, however the mechanism of this difference is unknown. We examined sex-related differences in the safety of S-1 plus oxaliplatin (SOX) and S-1 plus cisplatin (CS) in 663 metastatic gastric cancer patients taking part in a phase III study. The incidences of leukopenia (odds ratio [OR] 1.9; P = .015), neutropenia (OR 2.2; P = .002), nausea (OR 2.0; P = .009), and vomiting (OR 2.8; P < .001) were increased in women versus men treated with SOX, while vomiting (OR 2.9; P < .001) and stomatitis (OR 1.8; P = .043) were increased in women versus men treated with CS. In contrast, male patients treated with CS experienced thrombocytopenia more often (OR 0.51; P = .009). The mean relative dose intensity of S-1 in SOX was 75.4% in women and 81.4% in men (P = .032). No difference in efficacy was observed between women and men undergoing either regimen. Sex-related differences in adverse reactions during SOX and CS treatment were confirmed in this phase III study. Further translational research studies are warranted to pursue the cause of this difference.

MR signal changes in superparamagnetic iron oxide nanoparticle-labeled macrophages in response to X irradiation.

To investigate whether MR signals associated with macrophages labeled with superparamagnetic iron oxide nanoparticles (SPIONs) change in response to X irradiation, we performed in vitro MRI of SPION-labeled macrophage-like J774A.1 cells that were subsequently X irradiated. We labeled the cells with ferucarbotran at a concentration of 10 µg iron/mL in culture medium for 16 h and subsequently performed X irradiation at doses of 0, 2, 10, or 20 Gy using a low-energy X-ray unit. On Days 3 and 6, we suspended the cells in agar at a concentration of 2 × 106 cells/mL and acquired multi-gradient echo and multi-spin echo images of the cell samples using a 3 T scanner to estimate R2 * and R2 . In addition, we microscopically investigated the relationship among the MR signal changes, intracellular SPIONs, and acidic organelles. Our data showed that X irradiation of labeled cells caused increased SPION deposition in lysosomes compared with the non-irradiated control. On Day 3, R2 * and R2 values in the 0 to 10 Gy irradiated samples were dose-dependently increased 5.4- and 1.5-fold compared with 17 ± 2 and 13 ± 1/s, respectively, in the non-irradiated control; these values plateaued at more than 10 Gy. Although the increases in R2 *, R2 , and SPION deposition were still observed in the 10 and 20 Gy samples on Days 6 and 7, the 2 Gy samples showed recovery in these parameters as cell growth was restored. Acidic organelles were temporarily increased in the irradiated cells, which suggests that the reduction in lysosomal acidity was not attributable to SPION deposition. In conclusion, X irradiation of macrophages can cause SPION deposition and R2 * and R2 elevation in a specific dose range. MRI of SPION-labeled and subsequently X-irradiated macrophages may be utilized as a novel technique for investigating macrophage responses to X irradiation.

Early tumor shrinkage and depth of response in patients with advanced gastric cancer: a retrospective analysis of a randomized phase III study of first-line S-1 plus oxaliplatin vs. S-1 plus cisplatin.

BACKGROUND: We investigated early tumor shrinkage (ETS) and depth of response (DpR) using data from the G-SOX study comparing S-1 plus oxaliplatin with S-1 plus cisplatin as the first-line treatment for advanced gastric cancer (AGC). METHODS: ETS was determined as % decrease in the sum of the longest diameters of the target lesions at the first evaluation of week 6 compared to baseline. DpR was the maximum % shrinkage during the study treatment. The impact of ETS (cutoff value 20%) and DpR (continuous value) on progression-free survival (PFS) and overall survival (OS) were assessed by the log-rank test and Cox regression analysis including prognostic factors obtained in the G-SOX study; ECOG performance status, baseline sum of tumor diameters, disease status (recurrent/unresectable), and histology (diffuse/intestinal). RESULTS: Among 685 patients enrolled in the G-SOX study, 632 patients who had the first tumor evaluation were analyzed. Patients with ETS ≥ 20% had longer PFS (median 4.5 vs. 2.8 months, p < 0.0001) and OS (median 14.8 vs. 10.5 months, p < 0.0001) than those with ETS < 20%. Adjusted hazard ratios of ETS < 20 vs. ≥ 20% were 0.606 (95% confidence interval (CI) 0.506-0.725) for PFS and 0.589 (95% CI 0.492-0.704) for OS. DpR was also significantly associated with PFS and OS (both p < 0.0001). These results were similar between the SOX and CS groups. CONCLUSIONS: In AGC patients receiving the first-line therapy, ETS and DpR might be predictors for PFS and OS.

Peritoneal metastasis as a predictive factor for nab-paclitaxel in patients with pretreated advanced gastric cancer: an exploratory analysis of the phase III ABSOLUTE trial.

BACKGROUND: In the ABSOLUTE trial, weekly nanoparticle albumin-bound paclitaxel (w-nab-PTX) showed non-inferiority to weekly solvent-based paclitaxel (w-sb-PTX) for overall survival (OS). Thus, w-nab-PTX might be an option for second-line chemotherapy in advanced gastric cancer (AGC). However, predictive factors for efficacies of these agents have not been evaluated. METHODS: Patients previously enrolled in the ABSOLUTE trial were divided into apparent peritoneal metastasis group (PM group) and no apparent peritoneal metastasis group (no PM group) based on baseline imaging evaluated by RECIST ver. 1.1 criteria and amount of ascites. OS, progression-free survival, and overall response rate were compared between two arms in each group. RESULTS: This study included 240 and 243 patients in the w-nab-PTX and w-sb-PTX arms, respectively. In the PM group, the w-nab-PTX arm (n = 88) had longer OS than the w-sb-PTX arm (n = 103), and median survival time (MST) of 9.9 and 8.7 months [hazard ratio (HR) 0.63; 95% CI 0.45-0.88; P = 0.0060], respectively. In the no PM group, the w-nab-PTX arm (n = 140) had shorter OS than the w-sb-PTX arm (n = 152), and MST of 11.6 and 15.7 months (HR 1.40; 95% CI 1.06-1.86; P = 0.0180), respectively. After adjusting for prognostic factors, the HR for OS in the w-nab-PTX arm versus the w-sb-PTX arm was 0.59 (95% CI 0.42-0.83; P = 0.0023; PM group) and 1.34 (95% CI 1.01-1.78; P = 0.0414; no PM group), with significant interaction between treatment efficacy and presence of peritoneal metastasis (P = 0.0003). CONCLUSIONS: The presence of apparent peritoneal metastasis might be a predictive factor for selecting w-nab-PTX for pretreated AGC patients. TRIAL REGISTRATION NUMBER: JapicCTI-132059.