Orally administered Streptococcus thermophilus YIT 2001 is a vehicle for the delivery of glutathione, a reactive reduced thiol, to the intestine

AIMS

We aimed to analyze the behavior of cellular glutathione of Streptococcus thermophilus strain YIT 2001 (ST-1) in the gastrointestinal environment to understand how orally administered glutathione in ST-1 cells is delivered stably to the intestine in a reactive form, which is essential for its systemic bioavailability against lipid peroxidation.

METHODS AND RESULTS

Intracellular glutathione was labeled with L-cysteine-containing stable isotopes. ST-1 cells from fresh culture or lyophilized powder were treated with simulated gastric and intestinal juices for 60 min each. The release of intracellular glutathione in digestive juices was quantified via LC-MS/MS. Most of the cellular glutathione was retained in the gastric environment and released in response to exposure to the gastrointestinal environment. During digestion, the membrane permeability of propidium iodide increased significantly, especially when cells were exposed to cholate, without change in the cell wall state.

CONCLUSIONS

ST-1 cells act as vehicles to protect intracellular reactive components, such as glutathione, from digestive stress, and release them in the upper intestine owing to the disruption of membrane integrity induced by bile acid.

Randomized phase II trial of chemoradiotherapy with S-1 versus combination chemotherapy with gemcitabine and S-1 as neoadjuvant treatment for resectable pancreatic cancer (JASPAC 04)

OBJECTIVE

The aim of the present study was to investigate which treatment, neoadjuvant chemoradiotherapy (NAC-RT) with S-1 or combination neoadjuvant chemotherapy with gemcitabine and S-1 (NAC-GS), is more promising as neoadjuvant treatment (NAT) for resectable pancreatic cancer in terms of effectiveness and safety.

METHODS

In the NAC-RT with S-1 group, the patients received a total radiation dose of 50.4 Gy in 28 fractions with oral S-1. In the NAC-GS group, the patients received intravenous gemcitabine at a dose of 1000 mg/m2 with oral S-1 for two cycles. The primary endpoint was the 2-year progression-free survival (PFS) rate. The trial was registered with the UMIN Clinical Trial Registry as UMIN000014894.

RESULTS

From April 2014 to April 2017, a total of 103 patients were enrolled. After exclusion of one patient because of ineligibility, 51 patients were included in the NAC-RT with S-1 group, and 51 patients were included in the NAC-GS group in the intention-to-treat analysis. The 2-year PFS rate was 45.0% (90% confidence interval [CI]: 33.3%-56.0%) in the NAC-RT with S-1 group and 54.9% (42.8%-65.5%) in the NAC-GS group (p = .350). The 2-year overall survival rate was 66.7% in the NAC-RT with S-1 group and 72.4% in the NAC-GS group (p = .300). Although leukopenia and neutropenia rates were significantly higher in the NAC-GS group than in the NAC-RT with S-1 group (p = .023 and p < .001), other adverse events of NAT and postoperative complications were comparable between the two groups.

CONCLUSION

Both NAC-RT with S-1 and NAC-GS are considered promising treatments for resectable pancreatic cancer.

Risk factors for early recurrence in patients with pancreatic ductal adenocarcinoma who underwent curative resection

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers, and surgical resection is the only potentially curative approach. However, the rate of recurrence remains high, particularly within the first 6 months, and is associated with a poor prognosis. The present study evaluated the clinical characteristics and risk factors for early recurrence in pancreatic ductal adenocarcinoma (PDAC) patients who underwent curative resection, regardless of the use of neoadjuvant chemotherapy, to identify predictive factors associated with early recurrence and poor outcomes as well as to determine the optimal treatment strategy for patients at high risk of early recurrence after surgical resection.

METHODS

Patients who underwent pancreatic resection for PDAC at our institution from 2013 to 2021 were included in this study. We investigated the clinicopathological features of patients in groups: those with recurrence within 6 months, recurrence between 6 and 12 months, and recurrence beyond 12 months or no recurrence. A logistic regression analysis identified covariates associated with early recurrence at 6 and 12 months.

RESULTS

The study included 403 patients with a median follow-up of 25.7 months. Recurrence was observed in 279 patients, with 14.6% recurring within 6 months, 23.3% within 6-12 months, and 62% after 12 months or not at all. The preoperative CA19-9 level, modified Glasgow prognostic score (mGPS), and positive peritoneal cytology were significant risk factors for early recurrence within 6 months, while positive peritoneal cytology, lymph node metastasis, and the absence of adjuvant chemotherapy were significant risk factors for recurrence within 12 months. For patients who received preoperative chemotherapy or chemoradiotherapy, the preoperative CA19-9 level, mGPS, and positive peritoneal cytology were significant independent risk factors for early recurrence within 6 months, while positive peritoneal cytology, lymph node metastasis, and the absence of adjuvant chemotherapy were significant independent risk factors for recurrence within 12 months. The study concluded that the overall survival after surgical resection for potentially resectable PDAC worsened according to the number of risk factors present in the patient.

CONCLUSIONS

We clarified that preoperative CA19-9, positive peritoneal cytology, and the lack of adjuvant chemotherapy were consistent predictors for early recurrence within 6 and 12 months. In addition, an increased number of risk factors affecting the patient was associated with a poorer overall survival after potentially curable resection. Calculating the number of risk factors for early recurrence may be an essential predictive factor when considering treatment strategies.

Cost-effectiveness of 12 months of capecitabine as adjuvant chemotherapy for stage III colon cancer: preplanned cost-effectiveness analysis of the JFMC37-0801 study

OBJECTIVES

We evaluated the cost-effectiveness of a 12-month regimen of oral capecitabine versus a standard 6-month regimen as postoperative adjuvant chemotherapy for stage III colon cancer.

METHODS

We utilized patient-level data from a multi-institutional randomized controlled trial (JFMC37-0801) that investigated prolonged oral fluoropyrimidine monotherapy. The analysis considered three health states: stable disease, post-metastasis, and death. A parametric statistical model with a cure model was used to estimate the survival curve. The analysis was conducted from the Japanese public healthcare payer's perspective, considering only direct medical costs. A lifetime horizon was used, with a discount rate of 2% for both cost and health outcomes. Health outcomes were evaluated in terms of quality-adjusted life-years (QALYs).

RESULTS

The estimated cure rates for colon cancer were 0.726 [95% confidence interval (CI) 0.676-0.776] and 0.694 (95% CI 0.655-0.733) with the 12- and 6-month regimens, respectively; and the estimated 5-year relapse-free survival rates were 74.4% and 69.8%, respectively. The estimated lifetime cost for 12 months of capecitabine was JPY 3.365 million (USD 31,159), compared with JPY 3.376 million (USD 31,262) for 6 months. The estimated QALY were 12.48 and 11.77 for the 12- and 6-month regimens, respectively. Thus, the 12-month capecitabine regimen was dominant. Using a willingness-to-pay threshold of JPY 5 million per QALY, we determined a 97.4% probability that the 12-month capecitabine regimen is more cost-effective than the 6-month regimen.

CONCLUSIONS

Twelve months of capecitabine is the favorable option for postoperative adjuvant chemotherapy for stage III colon cancer from the perspective of cost-effectiveness.

An easy, rapid, and sensitive method for detection of drug-resistant influenza virus by using a sialidase fluorescent imaging probe, BTP3-Neu5Ac

Immunochromatographic kits and RT-PCR are widely used as diagnostic tools for influenza detection in clinical and hygiene fields. Immunochromatographic kits are useful for differential typing of influenza A and influenza B but cannot show if the detected virus strains have acquired drug resistance against neuraminidase inhibitors that target sialidase activity of viral neuraminidase. Although RT-PCR enables determination of drug-resistant mutants, its efficacy is limited to viruses carrying a known substitution in their neuraminidase genome sequence. In the present study, an easy, rapid and sensitive method for detection of drug-resistant influenza viruses regardless of major antigenic changes or genomic mutations was developed. By using the method in combination with virus-concentrated membranes in centrifugal filter units and a sialidase imaging probe, 2-(benzothiazol-2-yl)-4-bromophenyl-N-acetylneuraminic acid (BTP3-Neu5Ac), sialidase activity of influenza neuraminidase was visualized on membranes by the green fluorescence of produced hydrophobic BTP3 under UV irradiation with a handheld UV flashlight. Fluorescence images in the presence or absence of neuraminidase inhibitors clearly discriminated drug-resistant influenza viruses from drug-sensitive ones. The assay can be done within 15 min. The detection sensitivity was shown to be equal to or higher than the sensitivities of commercial immunochromatographic kits. The assay will be a powerful tool for screening and monitoring of emerging drug-resistant influenza viruses and would help clinicians decide effective antiviral treatment strategies when such mutants have become prevalent.