Current Development of Anti-Cancer Drug S-1

Developing targeted therapeutics for hepatocellular carcinoma: a critical assessment of promising phase II agents

INTRODUCTION

Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide and the first for primary liver tumors. In recent years greater therapeutic advancement was represented by employment of tyrosine kinase inhibitors (TKIs) either in monotherapy or in combination with immune checkpoint inhibitors (ICIs).

AREAS COVERED

Major attention was given to target therapies in the last couple of years, especially in those currently under phase II trials. Priority was given either to combinations of novel ICI and TKIs or those targeting alternative mutations of major carcinogenic pathways.

EXPERT OPINION

As TKIs are playing a more crucial role in HCC therapeutic strategies, it is fundamental to further expand molecular testing and monitoring of acquired resistances. Despite the recent advancement in both laboratory and clinical studies, further research is necessary to face the discrepancy in clinical practice.

Impact of CYP2A6 Gene Polymorphism on the Efficacy and Safety of S-1 Therapy in Patients with Gastric Cancer: A Systematic Review and Meta-Analysis

INTRODUCTION

The relationship of CYP2A6 polymorphisms with S-1 therapy outcomes in gastric cancer is unclear. This review aimed to assess the association between CYP2A6 gene polymorphisms (CYP2A6*4, *7, *9, *10) and S-1 therapy outcomes in gastric cancer, aiming to identify predictive markers for S-1 efficacy and adverse reactions.

METHODS

We searched seven databases, using random or fixed-effect models to calculate hazard ratio (HR) and 95% confidence interval (CI) based on study heterogeneity.

RESULTS

A total of 1,143 articles were retrieved from multiple online databases as of March 28, 2023. After screening, seven articles containing seven investigations were included in the meta-analysis. Our results revealed a significant association between the CYP2A6 polymorphism site and the overall survival (OS) of variant/variant group (V/V) patients compared to wild-type/wild-type (W/W) or wild-type/variant (W/V) patients (HR = 2.73, 95% CI: 1.45-5.14, p = 0.002). S-1 was more beneficial for W/W or W/V patients than V/V patients in terms of progression-free survival (PFS) (HR = 3.15, 95% CI: 1.47-6.75, p = 0.003). There was no association between CYP2A6 polymorphism and hematological adverse reactions (OR = 0.52, 95% CI: 0.23-1.15, p = 0.104).

CONCLUSION

CYP2A6 polymorphisms correlate with S-1 efficacy (OS and PFS) in gastric cancer, suggesting their potential as predictive markers. However, the generalizability of findings is limited by the small number of studies from Eastern countries and variations in chemotherapy regimens and detection methods. Further, large-scale studies are needed to confirm these associations.

Practical Consensus Guidelines for the Use of S-1 in GI Malignancies

Purvish M ParikhS-1 (5-fluorouracil prodrug [tegafur] in combination with 5-chloro-2,4-dihydroxypyridine [CDHP] and potassium oxonate [OXO]) was first approved in 1999. In order to make it easy for community oncologists, we decided to put together this expert consensus guideline for its use in gastrointestinal (GI) malignancies. A total of 15 subject matter experts used modified Delphi method to discuss, analyze, and vote on key aspects regarding practical approach to use of S-1 in GI cancers, a process involving 6 months of work. The consensus guidelines specify how S-1 use can be optimized in patients with colorectal, gastric, and pancreatic tumors. The voting for the 17 key points resulted in a majority consensus for all the statements (approval ranging from 13/15 [87%] to 15/15 [100%]). S-1 is a combination of three drugs (tegafur, CDHP, and OXO) specifically designed to reduce toxicity and enhance efficacy; clinical data and meta-analysis confirm both factors; and it is recommended as standard of care for GI cancers. S-1 is approved and one of the standards of care for all lines of therapy in colorectal cancer and pancreatic cancers. S-1 with oxaliplatin is the standard of care for gastric cancers.

Maintenance therapy improves the survival outcomes of patients with metastatic nasopharyngeal carcinoma responding to first-line chemotherapy: a multicentre, randomized controlled clinical study

PURPOSE

To explore the safety and role of tegafur/gimeracil/oteracil (S1) maintenance therapy (MT) in metastatic nasopharyngeal carcinoma (NPC) patients after response to first-line chemotherapy and to assess outcome-associated biomarkers.

METHODS

This was a multicentre, open-label, randomized controlled study involving metastatic NPC patients recruited (from May 2015 to May 2019) at five hospitals in China. The participants were randomized to S1-MT (receiving S1 MT until disease progression or intolerance) or non-MT (followed up until disease progression) groups. The primary endpoint was the progression-free survival (PFS). The secondary endpoints were the overall survival (OS), the correlation between EBV-DNA, serum amyloid A (SAA) status, and outcomes after the first-line chemotherapy, and safety.

RESULTS

The median follow-up was 24.3 months; 88 and 95 participants were evaluable in the S1-MT and non-MT groups, respectively. Compared with non-MT, S1-MT prolonged PFS (16.9 vs. 9.3 months, P < 0.001) and OS (33.6 vs. 20.6 months, P < 0.001). Regardless of their EBV-DNA status after first-line chemotherapy, participants were able to benefit from S1 MT, but EBV-DNA-positive participants benefited more significantly (PFS: HR = 0.600, 95% CI = 0.373-0.965, P = 0.035; OS: HR = 0.393, 95% CI = 0.227-0.681, P = 0.001). MT only improved PFS and OS in patients with an SAA decline after first-line chemotherapy (PFS: HR = 0.570, 95% CI = 0.350-0.919, P = 0.021; OS: HR = 0.404, 95% CI = 0.230-0.709, P = 0.002). The median S1 treatment was 23 cycles. Grade 1-2 skin pigmentation, oral mucositis, and hand and foot syndrome were the main adverse reactions.

CONCLUSION

For metastatic NPC patients with first-line chemotherapy response, S1 MT can improve PFS and OS, with good tolerability. EBV-DNA and SAA can better help us identify patients who can benefit from MT after standard treatment.

TRIAL REGISTRATION

The study protocol was registered at the Chinese Clinical Trial Registry (ChiCTR-IOR-16007939).

Synthesis, characterization, and anticancer evaluation of 1,3-bistetrahydrofuran-2yl-5-FU as a potential agent for pancreatic cancer

The failure of current chemotherapeutic agents for pancreatic cancer (PCa) makes it the most aggressive soft tissue tumor with a 5-year survival of slightly above 10% and is estimated to be the second leading cause of cancer death by 2030.

OBJECTIVE

The main aim was to synthesize, characterize and evaluate the anticancer activity of 1,3-bistetrahydrofuran-2yl-5FU (MFU).

METHODS

MFU was synthesized by using 5-fluorouracil (5-FU) and tetrahydrofuran acetate, and characterized by nuclear magnetic resonance (NMR), micro-elemental analysis, high-performance liquid chromatography (HPLC), and liquid chromatography with mass spectrophotometry (LC-MS). MFU and Gemcitabine hydrochloride (GemHCl) were tested for antiproliferative activity against MiaPaca-2 and Panc-1 cell lines.

RESULTS

The half-minimum inhibitory concentration (IC50) of MFU was twice lower than that of GemHCl when used in both cell lines. MiaPaca-2 cells (MFU-IC50 = 4.5 ± 1.2 μM vs. GemHCl-IC50 = 10.3 ± 1.1 μM); meanwhile similar trend was observed in Panc-1 cells (MFU-IC50 = 3.0 ± 1 μM vs. GemHCl-IC50 = 6.1 ± 1.03 μM). The MFU and GemHCl effects on 3D spheroids showed a similar trend (IC50-GemHCl = 14.3 ± 1.1 μM vs. IC50-MFU = 7.2 ± 1.1 μM) for MiaPaca-2 cells, and (IC50-GemHCl = 16.3 ± 1.1 μM vs. IC50-MFU = 9.2 ± 1.1 μM) for Panc-1 cells. MFU significantly inhibited clonogenic cell growth, and induced cell death via apoptosis. Cell cycle data showed mean PI for GemHCl (48.5-55.7) twice higher than MFU (24.7 to 27.9) for MiaPaca-2 cells, and similarly to Panc-1 cells. The in-vivo model showed intensely stained EGFR (stained brown) in all control, GemHCl and MFU-treated mice bearing subcutaneous PDX tumors, however, HER2 expression was less stained in MFU-treated tumors compared to GemHCl-treated tumors and controls. Mean tumor volume of MFU-treated mice (361 ± 33.5 mm3) was three-fold lower than GemHCl-treated mice (1074 ± 181.2 mm3) bearing pancreatic PDX tumors.

CONCLUSION

MFU was synthesized with high purity and may have potential anticancer activity against PCa.

Resistance to Gemcitabine in Pancreatic Ductal Adenocarcinoma: A Physiopathologic and Pharmacologic Review

Pancreatic ductal adenocarcinoma (PDAC) is a very aggressive tumor with a poor prognosis and inadequate response to treatment. Many factors contribute to this therapeutic failure: lack of symptoms until the tumor reaches an advanced stage, leading to late diagnosis; early lymphatic and hematic spread; advanced age of patients; important development of a pro-tumoral and hyperfibrotic stroma; high genetic and metabolic heterogeneity; poor vascular supply; a highly acidic matrix; extreme hypoxia; and early development of resistance to the available therapeutic options. In most cases, the disease is silent for a long time, andwhen it does become symptomatic, it is too late for ablative surgery; this is one of the major reasons explaining the short survival associated with the disease. Even when surgery is possible, relapsesare frequent, andthe causes of this devastating picture are the low efficacy ofand early resistance to all known chemotherapeutic treatments. Thus, it is imperative to analyze the roots of this resistance in order to improve the benefits of therapy. PDAC chemoresistance is the final product of different, but to some extent, interconnected factors. Surgery, being the most adequate treatment for pancreatic cancer and the only one that in a few selected cases can achieve longer survival, is only possible in less than 20% of patients. Thus, the treatment burden relies on chemotherapy in mostcases. While the FOLFIRINOX scheme has a slightly longer overall survival, it also produces many more adverse eventsso that gemcitabine is still considered the first choice for treatment, especially in combination with other compounds/agents. This review discusses the multiple causes of gemcitabine resistance in PDAC.

Synthesis of 5-fluorouracil-lactoside derivatives and experimental study on their anti-oral squamous cell carcinoma activity

OBJECTIVES

To reduce the toxicity of 5-fluorouracil (5-FU), design and synthesize 5-FU-lactoside derivatives, and preliminarily study their antitumor activities.

METHODS

Target compounds were prepared with Vorbrüggenglycation procedures, the structures were characterized through high resolution mass spectrometry (HRMS), 1H nuclear magnetic resonance (1HNMR), carbon-13 nuclear magnetic resonance (13CNMR), heteronuclear multiple quantum correlation (HMQC), and heteronuclear multiple bond correlation (HMBC). A cell counting kit (CCK)-8 test was performed to examine their in vitro toxicity and antitumor activity. Experimental data were tested by χ2, and statistically significant differences were denoted by P<0.05.

RESULTS

The target compounds were synthesized through a simple and efficient method. 1HNMR, 13CNMR, HMQC, HMBC, and HRMS confirmed that Ⅰa and Ⅰb were 5-FU nucleoside derivatives substituted with lactoside groups at N-1 and N-3, respectively. The CCK-8 test verified that high concentrations (0.7 μmol·mL-1) of Ⅰa and Ⅰb inhibited the growth of normal oral keratinocytes (NOK) by 30.28% and 50.68% after 24 h of treatment. Both values were lower than the inhibitory effect of 5-FU (68.22%; P<0.05). Ⅰb had a significant inhibitory effect on the growth of two oral squamous cell carcinoma cell lines. The inhibition rates of Cal-27 cells and UM SCC-47 cells treated with 0.7 μmol·mL-1 for 24 h were 81.20% and 80.19%, respectively.

CONCLUSIONS

Ⅰa and Ⅰb are less toxic than 5-FU. The antitumor activity of Ⅰb against oral squamous cell carcinoma cells is more obvious than that of Ⅰa.

Surgery alone, adjuvant tegafur/gimeracil/octeracil (S-1), or platinum-based chemotherapies for resectable gastric cancer: real-world experience and a propensity score matching analysis

Background

Adjuvant chemotherapy has changed the paradigm in resectable gastric cancer. S-1 is an oral chemotherapeutic with promising efficacy in Asia. However, comparisons with close observation or platinum-based doublets post D2 gastrectomy have been less reported, notably on real-world experiences.

Methods

We retrospectively evaluated patients with D2-dissected stage IB-III gastric cancer who received S-1 (S-1, n = 67), platinum-based doublets (P, n = 145) and surgery with close observation (OBS, n = 221) from Jan 2008 to Oct 2018. A propensity score matching was used to compare for recurrence-free (RFS) and overall survivals (OS) in patients who had a locally-advanced disease (T3–4 or lymph node-positive). Adverse reactions, dosage, and associated factors for S-1 are also discussed.

Results

In a median follow-up time of 51.9 months, adjuvant S-1 monotherapy was associated with an intermediate survival as compared with P and OBS (median RFS/OS: S-1 vs. P, 20.9/35.8 vs. 31.2/50.5 months, HR = 1.76/2.14, p = 0.021/0.008; S-1 vs. OBS, 24.4/40.2 vs. 20.7/27.0 months, HR = 0.62/0.55, p = 0.041/0.024). The survival differences were more prominent in patients with N2–3 diseases. S-1 was well-tolerated with a relative dose intensity of 73.6%, a median duration of 8.3 months and associated with less adverse reactions as compared with P. S-1 monotherapy was selected by physicians based on age, lymph node stage, serum carcinoembryonic antigen and disease stage.

Conclusions

Adjuvant S-1 correlated with intermediate survival outcomes between OBS and P but conferred fewer adverse reactions as compared with P. Patients with a moderate risk of recurrence had comparable survivals when treated with S-1 while platinum-based doublets were favored in advanced cases. The study provides additional information about adjuvant S-1 in patients with selected risk of recurrence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08487-z.

Diagnostic, Predictive and Prognostic Molecular Biomarkers in Pancreatic Cancer: An Overview for Clinicians

Pancreatic ductal adenocarcinoma (PDAC) is the most common pancreatic malignancy and is associated with aggressive tumor behavior and poor prognosis. Most patients with PDAC present with an advanced disease stage and treatment-resistant tumors. The lack of noninvasive tests for PDAC diagnosis and survival prediction mandates the identification of novel biomarkers. The early identification of high-risk patients and patients with PDAC is of utmost importance. In addition, the identification of molecules that are associated with tumor biology, aggressiveness, and metastatic potential is crucial to predict survival and to provide patients with personalized treatment regimens. In this review, we summarize the current literature and focus on newer biomarkers, which are continuously added to the armamentarium of PDAC screening, predictive tools, and prognostic tools.

Involvement of cytochrome P450 enzymes in inflammation and cancer: a review

Cytochrome P450 (CYP) enzymes are responsible for the biotransformation of drugs, xenobiotics, and endogenous substances. This enzymatic activity can be modulated by intrinsic and extrinsic factors, modifying the organism's response to medications. Among the factors that are responsible for enzyme inhibition or induction is the release of proinflammatory cytokines, such as interleukin-1 (IL-1), IL-6, tumor necrosis factor α (TNF-α), and interferon-γ (IFN-γ), from macrophages, lymphocytes, and neutrophils. These cells are also present in the tumor microenvironment, participating in the development of cancer, a disease that is characterized by cellular mutations that favor cell survival and proliferation. Mutations also occur in CYP enzymes, resulting in enzymatic polymorphisms and modulation of their activity. Therefore, the inhibition or induction of CYP enzymes by proinflammatory cytokines in the tumor microenvironment can promote carcinogenesis and affect chemotherapy, resulting in adverse effects, toxicity, or therapeutic failure. This review discusses the relevance of CYPs in hepatocarcinoma, breast cancer, lung cancer, and chemotherapy by reviewing in vitro, in vivo, and clinical studies. We also discuss the importance of elucidating the relationships between inflammation, CYPs, and cancer to predict drug interactions and therapeutic efficacy.

Rapidly progressive glomerulonephritis caused by tegafur/gimeracil/oteracil resulted in diabetes nephropathy, in a patient with minor risk of diabetes nephropathy: a case report

A 79-year-old Japanese male with a history of type 2 diabetes mellitus (T2DM) for 16 years was admitted to evaluate possible renal disease. The T2DM was well controlled in this patient using nutrition therapy without the need for any diabetes medication, and both diabetes retinopathy and proteinuria were negative. At the age of 78 advanced colorectal cancer (stage IIIa) was diagnosed and laparoscopic-assisted colectomy was performed. Following this procedure, the patient began treatment with tegafur/gimeracil/oteracil (S-1), 80 mg twice daily for 28 days of 42-day cycle. The patient received S-1 for 6 months, during which time, serum albumin decreased from 3.0 g/dL to 1.1 g/dL, urinary protein increased from negative to 3.0 g/day, and serum creatinine increased from 0.9 mg/dL to 2.1 mg/dL. Treatment with S-1 was discontinued, and furosemide 180 mg and prednisolone 30 mg treatment was initiated; however, serum creatinine levels continued to increase to 7.2 mg/dL and proteinuria continued to increase reaching a nephrotic range. A disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) activity was decreased to 27.0%. Renal biopsy showed Kimmelstiel-Wilson nodules, while immunofluorescence intensity of IgG subclass was IgG1 dominant, which was not compatible with diabetic nephropathy (DN). Plasma exchange was not affected. However, hemodialysis was initiated.The results of this investigation suggest that when S-1 monotherapy is performed in the case with DN, rapidly progressive glomerulonephritis (RPGN) may develop due to a condition similar to thrombotic microangiopathy, even in patients with a minor risk factor of DN.

Neoadjuvant apatinib plus S-1 in locally advanced pulmonary adenocarcinoma: A case report and review of the literature

RATIONALE

About one-third of the lung tumors are staged as locally advanced at the time of initial diagnosis; however, the optimal induction treatment before curative resection has not been elucidated. To date, the evidence regarding the preoperative apatinib plus S-1 for locally advanced pulmonary adenocarcinoma is scarce.

PATIENT CONCERNS

A 29-year-old female was admitted because of persistent cough, sputum, and chest distress for 2 months.

DIAGNOSES

Primary pulmonary adenocarcinoma (cT3N2M0, IIIB) with unknown driver gene mutation status.

INTERVENTIONS

The patient had received 4 months of neoadjuvant therapy using oral apatinib (425 mg daily) plus S-1 (60 mg, twice daily for 4 weeks with a 2-week drug-free interval), followed by anatomical lobectomy with curative intent. Adjuvant apatinib (425 mg daily for a month, and 250 mg daily for another month) plus S-1 at the same dosage were administered for 2 months. Thereafter, maintenance of low-dose S-1 monotherapy (40 mg, twice daily for 4 weeks with a 2-week drug-free interval) was continued for 6 months.

OUTCOMES

The adverse events were tolerable and well-controlled. A postoperative recurrence-free survival for 2 years and a half up to now was indicated.

LESSONS

Preoperative apatinib plus S-1 showed efficacy in locally advanced pulmonary adenocarcinoma. However, high-quality trials are warranted before the recommendation of this therapeutic regimen.

Maintenance chemotherapy using S-1 following definitive chemoradiotherapy in patients with N3 nasopharyngeal carcinoma

BACKGROUND

Patients with N3 stage nasopharyngeal carcinoma (NPC) are at high risk for treatment failure. This study aims to assess the efficacy of maintenance chemotherapy (MC) using S-1 (MC-S1), a novel oral fluoropyrimidine agent, following definitive chemoradiotherapy (CRT) using intensity-modulated radiotherapy (IMRT) in patients with N3 nasopharyngeal carcinoma (N3-NPC).

METHODS

A retrospective review was conducted for all N3-NPC treated with CRT with MC (CRT-MC) or without MC (CRT-non-MC) during 2014-2016. Toxicities with MC were recorded. Overall survival (OS), locoregional failure-free survival (LFFS) and distant metastasis free survival (DMFS) were compared between CRT-MC vs. CRT-non-MC cohorts.

RESULTS

A total of 130 N3 patients were identified, of whom 21 (16.2%) were treated with CRT-MC, and 109 (83.8%) with CRT-non-MC. Patient characteristics did not significantly differ between the CRT-MC and CRT-non-MC groups, with the exception of the number of cycles of neoadjuvant chemotherapy. Following IMRT 69 patients achieved a complete response (CR) (CRT-MC: 10; CRT-non-MC: 59), 61 had a partial response (PR) (11 vs. 50), and none maintained stable disease (SD) or developed progression of disease (PD). After a median follow-up of 41 months for surviving patients, a significant differences in OS (76.3% vs. 95.2%, p = 0.046) and DMFS (70.3% vs. 90.5%, p = 0.043) but not LFFS (84.9% vs. 100%, p = 0.091) at 3 years were observed between the CRT-non-MC and CRT-MC groups. Skin hyperpigmentation, leucopenia, fatigue, neutropenia, anorexia and nausea were the common but not severe (grade 1-2) toxicities of MC.

CONCLUSIONS

Using MC-S1 in N3-NPC patients following IMRT achieved superior survival to the CRT-non-MC patients. The toxicities of MC-S1 were mild and tolerable. Further clinical trials are required to evaluate the efficacy of MC-S1 in N3-NPC patients.

Pharmacokinetic and bioequivalence study between two formulations of S-1 in Korean gastric cancer patients

PURPOSE

S-1 is an oral fluoropyrimidine anticancer drug consisting of the 5-fluorouracil prodrug tegafur combined with gimeracil and oteracil. The purpose of this study was to evaluate the pharmacokinetic (PK), bioequivalence, and safety of a newly developed generic formulation of S-1 compared with the branded reference formulation, in Korean gastric cancer patients.

METHODS

This was a single-center, randomized, open-label, single-dose, two-treatment, two-way crossover study. Eligible subjects were randomly assigned in a 1:1 ratio to receive the test formulation or reference formulation, followed by a one-week washout period and administration of the alternate formulation. Serial blood samples were collected at 0 hrs (predose), 0.25, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, 12, 24, 36, and 48 hrs after dosing in each period. The plasma concentrations of tegafur, 5-FU, gimeracil, and oteracil were analyzed using a validated liquid chromatography-tandem mass spectrometry method. The PK parameters were calculated using a non-compartmental method.

RESULTS

In total, 29 subjects completed the study. All of the 90% confidence intervals (CIs) of the geometric mean ratios (GMRs) fell within the predetermined acceptance range. No serious adverse events were reported during the study.

CONCLUSION

The new S-1 formulation met the Korean regulatory requirement for bioequivalence. Both S-1 formulations were well tolerated in all subjects.Clinical trial registry: https://cris.nih.go.kr CRIS KCT0003855.

The combination of apatinib and S-1 for the treatment of advanced gastric cancer in China: A meta-analysis of randomized controlled trials

BACKGROUND

Apatinib-targeted therapy is considered a promising treatment option for malignancies. This study systematically evaluated the efficacy and safety of the combination of apatinib and S-1 for the treatment of patients with advanced gastric cancer (GC).

METHODS

Clinical trials were searched from the PubMed, Cochrane Library, Embase, CNKI, and Wanfang databases. Outcome measures including therapeutic efficacy, quality of life (QoL), and adverse events were extracted and evaluated.

RESULTS

Data from 8 trials including 393 patients with advanced GC were included. The results indicated that, compared with S-1 alone, the combination of apatinib with S-1 significantly improved patient partial response rate (odds ratio [OR] = 1.91, 95% confidence interval [CI] = 1.21-3.02, P = .005), overall response rate (ORR, OR = 2.40, 95% CI = 1.51-3.82, P = .0002), and disease control rate (DCR, OR = 2.78, 95% CI = 1.51-5.10, P = .0010), whereas the rates of complete response (CR, OR = 2.38, 95% CI = 0.93-6.12, P = .07) and stable disease (SD, OR = 0.99, 95% CI = 0.64-1.54, P = .97) and QoL (OR = 1.22, 95% CI = 0.51-2.92, P = .66) did not differ significantly. Moreover, the group receiving the combined therapy had higher rates of hand-foot syndrome (OR = 2.23, 95% CI = 1.19-4.17, P = .01), hypertension (OR = 8.85, 95% CI = 4.07-19.26, P < .00001), albuminuria (OR = 11.25, 95% CI = 3.32-38.06, P = .0001), and hemoglobin reduction (OR = 3.19, 95% CI = 1.32-7.67, P = .010), whereas analysis of other adverse events did not show significant differences (P > .05).

CONCLUSION

The combination of apatinib and S-1 is more effective for GC treatment than S-1 alone. However, this combined treatment could lead to increased hand-foot syndrome, hypertension, albuminuria, and hemoglobin reduction. Therefore, the benefits and risks should be considered before treatment.

A retrospective study of concurrent radiotherapy plus S-1 for treating advanced non-small cell lung cancer

We investigated the efficacy of concurrent radiotherapy plus S-1 (CRS) for treating unresectable stage III advanced non-small-cell lung cancer (ANSCLC).Seventy five ANSCLC patients were included in this retrospective study. Of those, 40 patients were assigned to an intervention group, and received S-1 (orally at 40 mg/m) twice daily for 14 consecutive days. Then, concurrent radiotherapy was administered in 2 Gy fractions, 5 times weekly for a total dose of 60 Gy. The other 35 patients were assigned to a control group, and underwent concurrent radiotherapy (the same as the intervention group) and cisplatin (60 mg/m on day 1 (CRC). The outcome measurements included overall response rate (ORR), overall survival (OS), progression-free survival (PFS), and toxicity.The 3-year ORR was 60.7% and 43.9% for intervention group and control group, respectively (P = .031). The median OS was 34.1 months and 25.3 months in the intervention and control groups, respectively (P = .041). The median PFS was 31.5 months for intervention group, while it was 22.4 months for control group (P = .048). No significant difference in toxicity was found between the 2 groups.The results demonstrated that the efficacy of CRS was superior to the CRC in ANSCLC patients with similar toxicity.

5-Chloro-2,4-dihydroxypyridine, CDHP, prevents lung metastasis of basal-like breast cancer cells by reducing nascent adhesion formation

A drug for metastasis prevention is necessary. The orally administered anticancer drug S‐1 contributes to cancer therapy. In a mouse xenograft model of metastatic breast cancer from our previous study, the administration of S‐1 inhibited lung metastasis. However, the mechanism of inhibition remains elusive. S‐1 contains 5‐chloro‐2,4‐dihydroxypyridine (CDHP), which does not have the antigrowth activity, but prevents the degradation of 5‐fluorouracil, an anticancer reagent. In this study, we found that CDHP treatment shrinks cell morphology in metastatic basal‐like breast cancer cell lines. Wound healing assays showed reduced cell migration in CDHP‐treated cells. At the molecular level, CDHP treatment reduced the number of nascent adhesions, whereas the number of mature focal adhesions was not changed. These findings indicate that CDHP impairs focal adhesion formation, which results in a reduction in cell migration. For the in vivo metastasis assay, we used a highly lung‐metastatic cell line. We xenografted them into immunodeficient mice, and administered CDHP. To determine whether CDHP prevents metastasis, we measured the weights of harvested lungs. The results showed that the lung weights of the CDHP‐treated animals were not significantly different compared to the no‐tumor controls, whereas the vehicle group showed a number of metastatic foci and an increase in lung weight. These observations indicate that CDHP administration prevents metastasis. This study reveals a novel effect of CDHP for lung metastasis prevention. Our findings may facilitate the establishment of future metastasis prevention therapies.

Nab-paclitaxel plus S-1 in advanced pancreatic adenocarcinoma (NPSPAC): a single arm, single center, phase II trial

This single-arm, phase II trial is to investigate efficacy and safety of nab-paclitaxel plus S-1 as first-line treatment in advanced pancreatic cancer. Nab-paclitaxel was administered at 120 mg/m² intravenously on day 1 and 8, S-1 was given twice a day orally on day 1-14 of each 21-day cycle, for 6 cycles. The primary endpoint was objective response rate (ORR), the secondary endpoints were progression-free survival (PFS), overall survival (OS) and safety. The ORR in intent-to-treat population (N=60) by either blinded independent review (BIR) or investigator assessment was 50.0%. Median PFS (mPFS) by BIR and median OS (mOS) were 5.6 months (95%CI, 4.6 to 6.6 m) and 9.4 months (95%CI, 8.0 to 10.8m), respectively. The most common grade 3 or 4 toxicities were leukopenia/neutropenia (35%) and fatigue (8.3%). Subgroup analyses based on BIR showed a remarkable ORR (>70%) was achieved in patients with female gender, ≥ 50% decline from baseline CA19-9, and developed grade 3 or 4 leukopenia/neutropenia. Remarkable survival benefit was statistically significant in female (mPFS: 7.7m, mOS: 18.2m), ≥ 50% decline from baseline CA19-9 (mPFS: 6.8m, mOS: 11.8m), objective responders (mPFS: 6.9m, mOS: 12.2m), and ECOG of 0 at baseline (mPFS: 7.5m, mOS: 16.1m). Nab-paclitaxel plus S-1 showed encouraging ORR and manageable toxicities, which is an effective alternative treatment regimen for advanced pancreatic cancer. (https://clinicaltrials.gov/ number, NCT02124317)

Intratumor dihydropyrimidine dehydrogenase mRNA expression levels are decreased in extramammary Paget's disease

S-1, a 5-fluorouracil (5-FU)-based anti-cancer agent, is an important drug for treating metastatic extramammary Paget's disease (EMPD). Although intratumor expression levels of 5-FU metabolism enzymes have been studied widely in many solid tumors, no studies have examined on the expression levels of thymidylate synthase (TS), orotate phosphoribosyl-transferase (OPRT) or dihydropyrimidine dehydrogenase (DPD) in skin cancers. The aim of this study was to estimate the intratumoral mRNA expression levels of these genes in EMPD by real time PCR. Intratumoral DPD mRNA levels were decreased in EMPD compared to those in normal skin, but its intratumoral DPD mRNA expression levels were not correlated with clinical manifestations. Intratumoral DPD mRNA levels were positively correlated with OPRT mRNA levels in EMPD. Based on these results, low expression of intratumoral DPD mRNA in EMPD may contribute to the pathogenesis of this disease.