Akitaka Makiyama

Schedule-dependent synergistic interaction between gemcitabine and oxaliplatin in human gallbladder adenocarcinoma cell lines

To define the most effective combination schedule of gemcitabine and oxaliplatin (L-OHP), we investigated the in-vitro interaction between these drugs in a panel of four human gallbladder adenocarcinoma cell lines (HAG-1, GB-d1, NOZ, and G-415). Cytotoxic activity was determined by the WST-1 assay. Different schedules of the two drugs were compared and evaluated for synergism, additivity, or antagonism with a quantitative method based on the median-effect principle of Chou and Talalay. Cell cycle perturbation and apoptosis were evaluated by flow cytometry. Simultaneous and sequential treatments of gemcitabine followed by L-OHP exhibited synergistic effects in all four cell lines, whereas the reverse sequence largely showed an antagonism. Gemcitabine exclusively arrested cells at the G0/G1 phase, and L-OHP at the G2/M phase, as measured by flow cytometric analyses. Apoptosis was most prominent when cells were treated simultaneously or in a sequence gemcitabine followed by L-OHP, producing apoptosis in treated cells (27–30%). In contrast, the reverse sequence yielded only 6–7% induction of apoptosis, the rate being not significantly different from those induced by each drug singly. Moreover, this sequence dependence was further confirmed by the experiment, which compared the number of HAG-1 cells 7 days after these combination schedules. These findings suggest that the interaction of gemcitabine and L-OHP is highly schedule dependent, with the most efficacious interaction observed in either simultaneous combination or in a sequence combination of gemcitabine followed by L-OHP.

A phase II trial of 1st-line modified-FOLFOXIRI plus bevacizumab treatment for metastatic colorectal cancer harboring RAS mutation: JACCRO CC-11

FOLFOXIRI plus bevacizumab is considered a standard initial therapy for metastatic colorectal cancer (mCRC). However, few prospective trials have evaluated triplet therapy plus bevacizumab in patients with RAS mutant mCRC. Patients with an age of 20 to 75 years, and unresectable, measurable tumors harboring RAS mutation were given first-line treatment with bevacizumab (5 mg/kg on day 1) plus modified-FOLFOXIRI (irinotecan 150 mg/m2, oxaliplatin 85 mg/m2, levofolinate 200 mg/m2, and fluorouracil 2400 mg/m2 as a 46-h continuous infusion on day 1, repeated every 2 weeks). The primary endpoint was the objective response rate (ORR) as evaluated by an external review board. Progression-free survival (PFS), overall survival, early tumor shrinkage (ETS), depth of response (DpR), and safety were secondary endpoints. Among 64 patients who were enrolled between October 2014 and August 2016, 62 were evaluable for efficacy (right-sided tumors in 27%). ORR and disease control rate were 75.8% (95% confidence interval [CI] 65.1-86.5) and 96.8%, respectively. ETS was 73.8%, and median DpR was 49.2%. Median PFS was 11.5 (95% CI 9.5-14.0) months as of the cut-off date of September 2017. Adverse events of grade 3 or 4 were neutropenia (54%), hypertension (32%), diarrhea (13%), anorexia (11%), peripheral neuropathy (2%), and febrile neutropenia (5%). In conclusion, this prospective trial demonstrated for the first time that FOLFOXIRI plus bevacizumab is an active first-line treatment for patients with RAS mutant mCRC. Modified-FOLFOXIRI plus bevacizumab might become an alternative regimen of triplet chemotherapy for mCRC in Japan.

Prophylactic Effect of Dexamethasone on Regorafenib-Related Fatigue and/or Malaise: A Randomized, Placebo-Controlled, Double-Blind Clinical Study in Patients with Unresectable Metastatic Colorectal Cancer (KSCC1402/HGCSG1402)

Background: Regorafenib is an oral multikinase inhibitor with a proven survival benefit for metastatic colorectal cancer patients. The KSCC1402/HGCSG1402 study investigated the prophylactic effect of oral dexamethasone (DEX) on regorafenib-related fatigue and/or malaise. Patients and Methods: Patients who progressed after standard chemotherapy were randomized 1: 1 to a DEX group (2 mg/day; days 1–28) with regorafenib or a placebo group with regorafenib. The primary endpoint was the incidence of fatigue and/or malaise, based on version 4.0 of the National Cancer Institute’s CTCAE (Common Terminology Criteria for Adverse Events). One of the secondary endpoints was the incidence of fatigue and/or malaise based on the CTCAE assessed by patient-reported outcome (PRO). Results: The incidence of any grade of fatigue and/or malaise assessed by the investigators was 58.8% in the DEX group and 61.1% in the placebo group (p = 0.8101), and that assessed by PRO was 47.2 and 58.3%, respectively (p = 0.3450). The incidence of grade ≥2 fatigue and/or malaise, as assessed by the investigators, was 19.4% for the DEX group and 38.9% for the placebo group (p = 0.0695), and that assessed by PRO was 27.8 and 52.8%, respectively (p = 0.0306). Conclusion: Our results suggest that prophylactic oral DEX is clinically effective in improving regorafenib-related fatigue and/or malaise.

A phase 2 study of fosaprepitant combined with high-dose dexamethasone for Japanese cancer patients receiving highly emetogenic chemotherapy

Purpose: Combination therapy of fosaprepitant, dexamethasone (DEX) and a serotonin (5-HT3) receptor antagonist is a standard antiemetic prophylaxis for patients receiving highly emetogenic chemotherapy (HEC). However, the appropriate dose of DEX has not been established in Japan. This study determined the efficacy and safety of triplet antiemetic prophylaxis in Japanese patients receiving HEC when administered the same doses of DEX as those given in a previous international phase 3 study on this drug. Methods: To assess the efficacy and safety of a sufficient dose of DEX (12 mg on day 1, 8 mg on day 2, 16 mg on days 3 and 4) in combination with intravenous fosaprepitant and granisetron, we prospectively examined patients receiving HEC including cisplatin (≥50 mg/m2). The primary endpoint was to determine the percentage of patients who had achieved a complete response (CR), which was defined as no vomiting and no rescue therapy during the entire treatment course. Results: Between February 2013 and January 2015, 44 patients were enrolled with a median age of 65 years (range, 30–75). There were 34 males (77.3%) in the study. Most of the patients had upper gastrointestinal cancers. The CR rate during the treatment course was 70% (95% confidence interval [CI]: 55%–83%) in the overall phase and 91% (95% CI: 78%–97%) in the acute phase and 70% (95% CI: 55%–83%) in the delayed phase. Appreciable severe toxicities related to the antiemetic therapy were not observed. Conclusions: These results suggest that a sufficient dose of DEX in combination with fosaprepitant and granisetron is optimal as an antiemetic prophylaxis for Japanese patients receiving HEC.

Role of Predictive Value of the Modified Glasgow Prognostic Score for Later-line Chemotherapy in Patients With Metastatic Colorectal Cancer

Micro‐Abstract The survival and safety of patients with metastatic colorectal cancer treated with trifluridine/tipiracil or regorafenib as later‐line chemotherapy were retrospectively examined according to the modified Glasgow Prognostic Score (mGPS). Overall and progression‐free survival were strongly correlated with mGPS in all patients. The frequency of adverse events was generally similar in each mGPS group. Background Assessment of patient factors is essential for selecting later‐line chemotherapy in patients with metastatic colorectal cancer (mCRC). The efficacy, prognosis, and safety of each treatment regimen according to nutritional and inflammatory status still remain to be elucidated. Patients and Methods A total of 550 patients with mCRC who were registered in the REGOTAS study (Regorafenib versus TAS‐102 as Salvage‐line in patients with colorectal cancer refractory to standard chemotherapies: a multicenter observational study, UMIN 000020416) and treated with trifluridine/tipiracil (TFTD) or regorafenib as a later‐line therapy were retrospectively stratified according to the modified Glasgow Prognostic Score (mGPS), which divided patients into mGPS 0 to 2 by serum albumin and C‐reactive protein, and compared. Results The median overall survival (OS) of patients with mGPS 0, 1, and 2 was 10.0 months (95% confidence interval [CI], 9.2‐11.6 months), 6.5 months (95% CI, 5.3‐7.1 months), and 3.9 months (95% CI, 3.3‐4.9 months), respectively. The median progression‐free survival (PFS) with mGPS 0, 1, and 2 was 2.5 months (95% CI, 2.1‐3.0 months), 2.0 months (95% CI, 1.9‐2.3 months), and 1.7 months (95% CI, 1.4‐1.9 months), respectively. There were significant differences by mGPS in both OS and PFS (all P < .001). No significant differences in OS and PFS were observed between the patient groups treated with TFTD and regorafenib in each mGPS group. In patients aged ≥ 65 years with mGPS 2, the OS and PFS were worse with regorafenib than with TFTD (OS: hazard ratio, 1.45; 95% CI, 0.93‐2.25; P = .097; PFS: hazard ratio, 1.57, 95% CI, 1.01‐2.44; P = .047), but there were no consistent trends observed as mGPS increased. The frequency of grade 3 and more adverse events was generally similar in each mGPS group. The multivariate analyses showed that mGPS was the strongest predictive factor for OS. Conclusions The mGPS before later‐line chemotherapy is strongly correlated with survival in patients with mCRC.

Epithelial-mesenchymal transition is activated in CD44-positive malignant ascites tumor cells of gastrointestinal cancer

Disseminated cancer cells in malignant ascites possess unique properties that differ from primary tumors. However, the biological features of ascites tumor cells (ATC) have not been fully investigated. By analyzing ascites fluid from 65 gastrointestinal cancer patients, the distinguishing characteristics of ATC were identified. High frequency of CD44+ cells was observed in ATC using flow cytometry (n = 48). Multiplex quantitative PCR (n = 15) showed higher gene expression of epithelial‐mesenchymal transition (EMT)‐related genes and transforming growth factor beta (TGF‐beta)‐related genes in ATC than in the primary tissues. Immunohistochemistry (n = 10) showed that ATC also had much higher expression of phosphorylated SMAD2 than that in the corresponding primary tissues. TGF‐beta 1 was detected in all cases of malignant ascites by enzyme‐linked immunoassay (n = 38), suggesting the possible interaction of ATC and the ascites microenvironment. In vitro experiments revealed that these ATC properties were maintained by TGF‐beta 1 in cultured ATC(n = 3). Here, we showed that ATCrevealed high frequencies of CD44 and possessed distinct EMT features from primary tissues that were mainly maintained by TGF‐beta 1 in the ascites.

Early tumor shrinkage indicates a favorable response to bevacizumab-based first-line chemotherapy for metastatic colorectal cancer

A close correlation between early tumor shrinkage (ETS) and overall survival (OS) has been shown in antiepidermal growth factor receptor antibody-based chemotherapies for metastatic colorectal cancer (mCRC), but the clinical impact of ETS in bevacizumab-based chemotherapy has not been adequately clarified. Clinical data of mCRC patients who started initial chemotherapy without antiepidermal growth factor receptor antibody from 2005 to 2010 were retrospectively evaluated. The relative change in tumor size after 8 weeks of chemotherapy expected from the first image assessment [estimated ETS (EETS)] and the relative change in the tumor size at the nadir compared with the baseline [depth of response (DPR)] were examined. Seventy-three patients were enrolled and 61 patients were evaluable for survival by simple regression analysis. Bevacizumab-based chemotherapies were administered to 40 (66%) patients. The median EETS, DPR, progression-free survival, and OS were 16.1%, 27.2%, 8.0 months, and 19.5 months, respectively. Progression-free survival showed a positive correlation with OS (R2=0.429), whereas EETS and DPR were less correlated with OS (R2=0.0682, 0.186). EETS was well correlated with DPR (R2=0.659). Patients with EETS greater than 16.12% were predicted to achieve tumor shrinkage of more than 30% at the maximum response. EETS in bevacizumab-treated mCRC showed a close correlation with DPR, which suggested that EETS might be useful, indicating a favorable response in treatment with bevacizumab-based chemotherapy.

Exploratory analysis of a prognosis predictive formula for metastatic colorectal cancer treated with chemotherapy.

757 Background: Progression free survival (PFS) has been recognized as a surrogate outcome in the therapy for metastatic or recurrent colorectal cancer (mCRC). As molecular targeted therapies have become to be widely used, new surrogate outcome such as early tumor shrinkage (ETS; the relative change in the sum of longest diameters of target lesions at week 8 compared to baseline) and deepness of response (DpR; the relative change in the sum of longest diameters of target lesions at the nadir compared to baseline) are proposed. However, their validity has not been fully proven. We conducted to develop a new prognosis predictive formula consisting of the three factors, DpR, ETS and PFS, in the first-line chemotherapy of mCRC. Methods: We retrospectively evaluated mCRC patients who started any chemotherapy from 2005 to 2010. Estimated ETS (eETS), instead of ETS, was defined as the estimated relative change of target lesions at week 8 calculated from first image assessment. DpR was defined as above. Predictiv...

Phase 2 Study of Modified Irinotecan and Bolus 5-Fluorouracil/l-Leucovorin in Japanese Metastatic Colorectal Cancer Patients

IntroductionUsing the recommended doses obtained from our previous phase 1 trial of a modified Saltz chemotherapy regimen for metastatic colorectal cancer (weekly irinotecan and bolus 5-fluorouracil/l-leucovorin for 3 weeks every 28 days), we performed the present phase 2 trial to evaluate efficacy and toxicity.MethodsA total of 29 patients with metastatic colorectal cancer were included. Our modified Saltz regimen was administered. The primary endpoint was overall response rate.ResultsOf the 29 patients, 11 had previous chemotherapy. A partial response occurred in 11 patients, stable disease in 16 patients, and progressive disease in two patients. Disease control rate was 93.1%. Response rates with and without previous treatment were 18.2% and 50%, respectively. Median progression-free survival was 17.3 months. The main hematologic toxicities were leukopenia (22.6%) and neutropenia (45.2%). No treatment-related deaths occurred.ConclusionOur modified Saltz regimen exhibited sufficient efficacy, feasibility, and manageable toxicity as a therapeutic option for selected colorectal cancer patients.