Synergistic effects of docetaxel and S-1 by modulating the expression of metabolic enzymes of 5-fluorouracil in human gastric cancer cell lines

Efficacy and safety of docetaxel plus S-1-based therapy in gastric cancer: a quantitative evidence synthesis of randomized controlled trials

Objective: To systematically evaluate the safety and efficacy of docetaxel plus S-1-based therapy in gastric cancer treatment. Methods: PubMed, Embase, The Cochrane Library, and Web of Science electronic databases were searched for randomized controlled trials on docetaxel plus S-1-based therapy in the treatment of gastric cancer from the establishment of the database to 1 September 2022. Relevant studies were included per pre-defined eligibility criteria, and two researchers independently screened and assessed the included literature using Review Manager v5. Outcome measures and statistics related with efficacy and safety profiles were extracted from the included studies, and Stata v15.1 was used for pooled analysis. Results: Objective response rate (odds ratio = 2.34, 95% CI = [1.32, 4.13], p = 0.003), relapse-free survival (HR = 0.68, 95% CI = [0.58, 0.79], p < 0.001), progression-free survival (HR = 0.81, 95% CI = [0.68, 0.96], p = 0.016), and overall survival (HR = 0.86, 95% CI = [0.79, 0.95], p = 0.002) of docetaxel plus S-1-based therapy (DS-based therapy) in gastric cancer treatment were better than those of the non-DS-based therapy. However, DS-based therapy was associated with increased risk of certain adverse drug effects, such as alopecia, leukopenia, and oral mucositis. Further studies are warranted to validate the efficacy superiority of DS-based versus non-DS-based regimens as per our trial sequential analysis findings. Conclusion: DS-based therapy significantly improves patients' clinical outcomes in gastric cancer, albeit at the cost of increased toxicity. Further RCTs are needed to confirm the efficacy superiority of DS-based regimens.

Updated Adjuvant Chemotherapy for Gastric Cancer

Surgical resection is currently the best curative approach for gastric cancer (GC); however, the prognosis of patients with advanced GC remains poor even with curative resection. For this reason, perioperative chemotherapy has been combined with surgery to reduce the risk of postoperative recurrence. Standard perioperative chemotherapy for resectable advanced GC varies from region to region. Postoperative S-1 therapy was standardized via the ACTS-GC study in East Asia, perioperative ECF (Epirubicin + Cisplatin + Fluorouracil) was standardized via the MAGIC study in Europe, and postoperative chemoradiotherapy was standardized via the US intergroup study in North America. Since then, more intensive regimens have been developed. In recent years, perioperative therapy using novel agents, such as molecular-targeted drugs and immune checkpoint inhibitors (ICIs), has also been tested and evaluated in the three major regions (East Asia, Europe, and North America) with promising results. Perioperative chemotherapy has become an integral part of many treatment strategies and requires continued research and evaluation.

Docetaxel and fluorouracil as first-line therapy for gastric cancer with bone marrow metastasis and disseminated intravascular coagulation

Gastric cancer with bone marrow metastasis and disseminated intravascular coagulation constitutes a highly aggressive gastric cancer subtype which presents a peculiar biological behavior and very poor prognosis. Retrospective studies have shown chemotherapy could prolong survival, but a prospective trial is still unavailable. This study is the first prospective clinical trial to evaluate the safety and efficacy of chemotherapy for advanced gastric cancer patients with bone marrow metastasis.

Utility of TMPRSS4 as a Prognostic Biomarker and Potential Therapeutic Target in Patients with Gastric Cancer

BACKGROUND

Transmembrane serine protease 4 (TMPRSS4) belongs to the family of type II transmembrane serine proteases that are known to be upregulated in many malignant tumors. However, there is a paucity of studies documenting the clinical impact and biological effects of TMPRSS4 on gastric cancer (GC) patients who underwent surgery.

METHODS

Tissues samples were obtained from 105 patients with GC who underwent gastrectomy followed by adjuvant chemotherapy, excluding those at stage I. The expression of TMPRSS4 was examined through immunohistochemical analysis. The association between TMPRSS4 expression and clinico-pathological features as well as prognosis was assessed. Moreover, the effects of TMPRSS4 expression on cell migration and sensitivity to 5-FU were investigated.

RESULTS

The expression rate of TMPRSS4 was 56.3% (59/105) in GC cases. The expression of TMPRSS4 was positively correlated with the depth of tumor (T) and venous (V) invasion. The 5-year overall survival (OS) and recurrence-free survival (RFS) rates of the TMPRSS4-positive group was significantly lower than that of the TMPRSS4-negative group (p=0.0001 and p=0.005, respectively). Especially, there was significant differences in OS and RFS of patients with stage III cancer between the two groups (p=0.0064 and 0.012, respectively). Multivariate analysis demonstrated that TMPRSS4 expression and the stage of cancer were crucial prognostic factors for RFS. TMPRSS4-silenced GC cells exhibited increased sensitivity to 5-FU when compared with the non-specific control siRNA-transfected cells.

CONCLUSION

TMPRSS4 can be considered as a potential prognostic biomarker, especially for stage III, and a promising therapeutic target for GC.

Extramammary Paget's Disease: Diagnosis, Pathogenesis, and Treatment with Focus on Recent Developments

Extramammary Paget’s disease (EMPD) is a rare neoplasm that usually develops in apocrine gland-bearing areas, such as the vulva, scrotum, and penis. EMPD may present with a focal, multifocal, or an ectopic lesion. Clinically, EMPD lesions often exhibit infiltrative erythema, which is sometimes similar to other skin disorders such as eczema. While primary EMPD arises as intraepithelial neoplasm of the epidermis, EMPD-like lesions may occur from epidermotropic spread of malignant cells or direct extension from an underlying internal neoplasm, known as secondary EMPD. Because treatment strategies differ for primary EMPD and secondary EMPD, accurate diagnosis based on detailed histopathological evaluation is required. In the early stages, EMPD usually shows indolent growth, and most cases are diagnosed as carcinoma in situ. However, invasive lesions may result in metastases, and deep invasion is associated with high incidence of metastases. Conventional chemotherapies have been used for EMPD treatment in patients with distant metastases, but the efficacy is not satisfactory, and the prognosis for such patients remains poor. Recent studies have provided various insights into the molecular pathogenesis of the development and advancement of EMPD, which may lead to novel treatment approaches for metastatic EMPD. This review addresses the diagnosis, pathogenesis, and treatment of EMPD with focus on recent progress in understanding this disease.

Phase I/II Study of Docetaxel and S-1 in Previously-Treated Patients with Advanced Non-Small Cell Lung Cancer: LOGIK0408

Background: As docetaxel plus S-1 may be feasible for cancer treatment, we conducted a phase I/II trial to determine the recommended docetaxel dose and the fixed S-1 dose (phase I), as well as confirm the regimen’s efficacy and safety (phase II) for previously-treated patients with advanced non-small cell lung cancer. Methods: Patients ≤75 years with performance status ≤1 and adequate organ function were treated at three-week intervals with docetaxel on day 1 and 80 mg/m² oral S-1 from days 1–14. The starting docetaxel dose was 45 mg/m² and this was escalated to a maximum of 70 mg/m². In phase II, response rate, progression-free survival (PFS), overall survival (OS), and safety were assessed. Results: The recommended doses were 50 mg/m² docetaxel (day 1) and 80 mg/m² S-1 (days 1–14). Grades 3 and 4 leukocytopenia and neutropenia occurred in 44% and 67% of patients, respectively. Nonhematologic toxicities were generally mild. Overall response to chemotherapy was 7.7% (95% confidence interval (CI), 1.6–20.9%), and median PFS and OS were 18.0 weeks (95% CI; 11.3–22.9 weeks) and 53.0 weeks, respectively. Conclusion: Fifty mg/m² docetaxel plus 80 mg/m² oral S-1 had a lower response rate than anticipated; however, the survival data were encouraging. A further investigation is warranted to select the optimal patient population.

Addition of Docetaxel to Oral Fluoropyrimidine Improves Efficacy in Patients With Stage III Gastric Cancer: Interim Analysis of JACCRO GC-07, a Randomized Controlled Trial

PURPOSE

S-1 is a standard postoperative adjuvant chemotherapy for patients with stage II or III gastric cancer in Asia. Neoadjuvant or perioperative strategies dominate in Western countries, and docetaxel has recently shown significant survival benefits when combined with other standard regimens in advanced cancer and perioperative settings.

PATIENTS AND METHODS

This randomized phase III study was designed to prove the superiority of postoperative S-1 plus docetaxel over S-1 alone for R0 resection of pathologic stage III gastric cancer. The sample size of 1,100 patients was necessary to detect a 7% increase in 3-year relapse-free survival as the primary end point (hazard ratio, 0.78; 2-sided α = .05; β = .2).

RESULTS

The second interim analysis was conducted when the number of events reached 216 among 915 enrolled patients (median follow-up, 12.5 months). Analysis demonstrated the superiority of S-1 plus docetaxel (66%) to S-1 (50%) for 3-year relapse-free survival (hazard ratio, 0.632; 99.99% CI, 0.400 to 0.998; stratified log-rank test, P < .001), and enrollment was terminated as recommended by the independent data and safety monitoring committee. Incidences of grade 3 or greater adverse events, particularly neutropenia and leukopenia, were higher in the S-1 plus docetaxel group, but all events were manageable.

CONCLUSION

Addition of docetaxel to S-1 is effective with few safety concerns in patients with stage III gastric cancer. The present findings may also be applicable in countries in which perioperative adjuvant chemotherapy or chemoradiation is not standard.

Phase II Study of S-1 Combined With Low-Dose Docetaxel as Neoadjuvant Chemotherapy for Operable Breast Cancer Patients (N-1 Study)

BACKGROUND

To improve the pathological complete response (pCR) rate, we devised new neoadjuvant chemotherapy. Efficacy and safety of the oral fluoropyrimidine derivative S-1 (Taiho Pharmaceutical Co, Tokyo, Japan) combined with low-dose docetaxel (S-1+DOC) were evaluated.

PATIENTS AND METHODS

Patients were treated with docetaxel (40 mg/m² intravenously on day 1) and S-1 (40 mg/m² orally twice per day on days 1-14) every 3 weeks for 4 cycles. In accord with the Response Evaluation Criteria In Solid Tumors version 1.1 criteria, the patients who showed a complete response (CR) underwent surgery, and those who achieved a partial response (PR) underwent 4 more cycles of S-1+DOC. Patients who achieved stable disease (SD) or progressive disease (PD) received EC (epirubicin and cyclophosphamide) or HT (trastuzumab and paclitaxel) according to their HER2 status. The primary end point was the pCR rate.

RESULTS

Ninety-four patients entered the study. After 4 cycles of S-1+DOC, CR was noted in 5 patients, PR in 57, SD in 18, and PD in 3. Of the patients who achieved SD and PD, 12 received EC, and 9 received HT. Among the 83 assessable patients, the pCR rate was 34.9%, and the response rate was 80.7%. The pCR rates were 19.5% in the luminal type group, 53.8% in the luminal HER2 group, 46.1% in the HER2 group, and 50.0% in the triple-negative group.

CONCLUSION

The S-1+DOC regimen in this study could be well tolerated and a new candidate neoadjuvant chemotherapy in operable breast cancer patients. It is also expected to be effective even in patients with luminal type disease. However, further randomized control trials are needed to ascertain whether pCR can contribute to favorable outcomes.

Therapeutic strategies with oral fluoropyrimidine anticancer agent, S-1 against oral cancer

Oral cancer has been recognized as a tumor with low sensitivity to anticancer agents. However, introduction of S-1, an oral cancer agent is improving treatment outcome for patients with oral cancer. In addition, S-1, as a main drug for oral cancer treatment in Japan can be easily available for outpatients. In fact, S-1 exerts high therapeutic effects with acceptable side effects. Moreover, combined chemotherapy with S-1 shows higher efficacy than S-1 alone, and combined chemo-radiotherapy with S-1 exerts remarkable therapeutic effects. Furthermore, we should consider the combined therapy of S-1 and molecular targeting agents right now as these combinations were reportedly useful for oral cancer treatment. Here, we describe our findings related to S-1 that were obtained experimentally and clinically, and favorable therapeutic strategies with S-1 against oral cancer with bibliographic considerations.

Role of definitive chemoradiotherapy using docetaxel and 5-fluorouracil in patients with unresectable locally advanced esophageal squamous cell carcinoma: a phase II study

Definitive chemoradiotherapy (CRT) with docetaxel (DOC) and 5-fluorouracil (5-FU) is a unique regimen for esophageal cancer. In this prospective phase II study, antitumor effect and safety of CRT using DOC and 5-FU for inoperable locally advanced esophageal cancer were evaluated. DOC 7.5 mg/m² was infused on days 1, 8, 22, and 29. 5-FU 250 mg/m² /day was infused continuously on days 1-5, 8-12, 15-19, 22-26, 29-33, 36-40, and 43-45. Radiotherapy was given to 66 Gy in 33 fractions. Eleven patients with thoracic and five with cervical esophageal cancer were eligible. All patients had esophageal squamous cell carcinoma (ESCC). The response rate was 94%, with complete response in five patients (31%) and partial response in 10 (63%). Hematologic toxicity was mild; only one patient (6%) had Grade 1 leukopenia. Nonhematologic Grade 3 or higher adverse events were esophagitis (31%), anorexia (6%), and esophago-bronchial fistula (6%). No treatment-related deaths occurred. The median time to progression was 20 months and overall 3-year and 5-year survival were 44% and 31%, respectively. Definitive CRT using DOC and 5-FU could be performed safely, and it demonstrated a favorable antitumor effect for ESCC. This regimen might be indicated in patients in whom it is desirable to avoid myelosuppression and progression of renal impairment.

A Multicenter Randomized Phase II Study of Docetaxel vs. Docetaxel Plus Cisplatin vs. Docetaxel Plus S-1 as Second-Line Chemotherapy in Metastatic Gastric Cancer Patients Who Had Progressed after Cisplatin Plus Either S-1 or Capecitabine

Purpose

This study evaluated the re-challenge of S-1 or cisplatin in combination with docetaxel in metastatic gastric cancer (MGC) that had progressed on a cisplatin plus either S-1 or capecitabine regimen.

Materials and Methods

Patients with progressive disease after first-line cisplatin plus S-1 or capecitabine were randomized to receive 3-week cycles of docetaxel 75 mg/m² intravenously (IV) on D1 (D), docetaxel 60 mg/m² IV plus cisplatin 60 mg/m² IV on D1 (DC), or docetaxel 60 mg/m² IV D1 plus oral S-1 30 mg/m² twice a day on D1-14 (DS).

Results

Seventy-two patients were randomized to the D (n=23), DC (n=24), or DS (n=25) group. The confirmed response rate was 4.3% (95% confidence interval [CI], 0% to 12.6%), 4.3% (95% CI, 0% to 12.6%), and 8.7% (95% CI, 0% to 20.2%) for the D, DC, and DS groups, respectively. Compared to the D arm, the DS arm had a better progression-free survival (2.7 months vs. 1.3 months, p=0.034) without any deterioration in safety or quality of life, whereas the DC arm had a similar progression-free survival (1.8 months vs. 1.3 months, p=0.804) and poorer overall survival (5.6 months vs. 10.0 months, p=0.035).

Conclusion

A re-challenge with S-1, but not cisplatin, in combination with docetaxel has potential anticancer benefits over docetaxel alone in MGC with progression after prior cisplatin plus S-1 or capecitabine.

Phase II trial of neoadjuvant chemotherapy with docetaxel, nedaplatin, and S1 for advanced esophageal squamous cell carcinoma

Although standard chemotherapy for esophageal cancer patients is fluorouracil and cisplatin, the prognosis is still unsatisfactory. A new therapeutic regimen combining docetaxel, cisplatin, and 5‐fluorouracil was recently developed to improve both local and distant tumor control. We developed a new regimen of docetaxel, nedaplatin, and S1 (DGS) and previously reported the recommended dose in a phase I dose‐escalation study. We then undertook a phase II study of DGS for advanced esophageal squamous cell carcinoma. Patients with clinical stage IB/II/III disease were eligible. Patients received two courses of chemotherapy: docetaxel 35 mg/m² with nedaplatin 40 mg/m² on day 8, 80 mg/m² S1 on days 1–14, and 2 weeks off. After completion of chemotherapy, patients underwent esophagectomy. The primary endpoint was the completion rate of protocol treatment (completion of two courses of preoperative chemotherapy and R0 surgery [no residual tumor]). We enrolled 32 patients. The completion rate of protocol treatment was 96.9%. During chemotherapy, the most common grade 3 or 4 toxicity was neutropenia (25.0%). No treatment‐related deaths were observed, and the incidence of operative morbidity was tolerable. The overall response rate after chemotherapy was 83.3%. This DGS regimen was well tolerated and highly active. This trial is registered with the University Hospital Medical Information Network (UMIN ID: 000014626).

Phase II trial of biweekly docetaxel, cisplatin, and 5-fluorouracil chemotherapy for advanced esophageal squamous cell carcinoma

The prognosis of esophageal cancer patients is still unsatisfactory. Although a docetaxel, cisplatin, and 5-Fu (DCF) regimen has been reported, it is often difficult to accomplish because of severe toxicity. Therefore, we developed a new biweekly DCF (Bi-DCF) regimen and previously reported the recommended dose in a phase I dose-escalation study. We then performed a phase II study of Bi-DCF for advanced esophageal squamous cell carcinoma (SCC). Patients with clinical stage II/III were eligible. Patients received 2 courses of chemotherapy: docetaxel 35 mg/m² with cisplatin 40 mg/m² on days 1 and 15 and 400 mg/m² 5-fluorouracil on days 1–5 and 15–19 every 4 weeks. After completion of the chemotherapy, patients received esophagectomy. The primary endpoint was the completion rate of protocol treatment. Thirty-two patients were enrolled. The completion rate of protocol treatment (completion of two courses of preoperative chemotherapy and R0 surgery) was 100 %. During chemotherapy, the most common grade 3 or 4 toxicities were neutropenia (31.3 %). No treatment-related death was observed, and the incidence of operative morbidity was tolerable. The overall response rate after the chemotherapy was 90.3 %. This Bi-DCF regimen was well tolerated and highly active. This trial was registered with the University Hospital Medical Information Network (No. UMIN 000014625).

Combination chemotherapy with S-1 and docetaxel for cutaneous angiosarcoma resistant to paclitaxel

The prognosis of cutaneous angiosarcoma is very poor compared with that of other skin malignancies. The main reason for this is the limited regimens of chemotherapy available for angiosarcoma, because it is resistant to most common chemotherapeutic agents. Therefore, there is an urgent need to identify new treatment options. Recently, S-1 and docetaxel therapy was reported to be effective for advanced gastric cancer and metastatic extramammary Paget's disease. Therefore, we treated paclitaxel-resistant angiosarcoma patient with S-1/docetaxel chemotherapy. The progression-free survival was 5.0 months although grade 3 adverse events such as diarrhea and neutropenia developed. Our data need to be confirmed in a large number of patients, but S-1/docetaxel chemotherapy as an additional regimen seems to be an effective treatment option for paclitaxel-resistant angiosarcoma.

Results of Neoadjuvant Chemoradiotherapy With Docetaxel and 5-Fluorouracil Followed by Esophagectomy to Treat Locally Advanced Esophageal Cancer

BACKGROUND

Esophageal cancer is most frequently treated with platinum-based chemoradiotherapy (CRT). We previously described a phase I study of definitive CRT with docetaxel (DOC) and 5-fluorouracil (5FU) in patients with advanced esophageal cancer. This regimen had low toxicity and was effective without platinating agents. The present study aims to determine the antitumor effects of neoadjuvant CRT with DOC and 5FU and surgical outcomes.

METHODS

We reviewed data from 38 patients with locally advanced cancer of the esophagus or esophagogastric junction who underwent trimodality therapy comprising neoadjuvant CRT with DOC and 5FU followed by esophagectomy between 2003 and 2008.

RESULTS

Esophagitis was the most common toxicity associated with neoadjuvant CRT (grade 3; 26.3%), and hematologic toxicity was mild. Transthoracic esophagectomy and pharyngolaryngoesophagectomy proceeded in 36 (94.7%) and 2 (5.3%) patients, respectively, and 35 (92.1%) underwent R0 resection. Five (13.2%) patients had complete pathologic responses (pCR) of the primary tumor, and 23 (60.5%) had pathologic reductions of over two-thirds of the primary tumor. The T or N status was also down-staged in 26 (68.4%) patients. Overall postoperative morbidity developed in 21 (55.3%) patients, and mortality due to postoperative morbidity was zero. The 5-year recurrence-free and overall survival rates were 39.5% and 44.7%, respectively.

CONCLUSIONS

The rates of neoadjuvant CRT toxicity and postoperative complications were acceptable, and the complete resection rate and survival data were favorable. This regimen is promising as neoadjuvant CRT for esophageal cancer and very useful as an alternative regimen for treating patients with esophageal cancer who cannot tolerate cisplatin.

Dose-dense biweekly docetaxel combined with 5-fluorouracil as first-line treatment in advanced gastric cancer: a phase II trial

This study evaluated the efficacy, safety and impact on quality of life (QoL) of a dose-dense biweekly regimen of docetaxel and 5-fluorouracil in first-line treatment of advanced gastric cancer (AGC). Eligible patients received docetaxel 60 mg/m(2) and 5-fluorouracil (400 mg/m(2) bolus followed by 2,400 mg/m(2) 46-h infusion), fortnightly. Prophylactic use of G-CSF was adopted in all patients. The primary end point was response rate (RR). Secondary end points were progression-free survival (PFS), overall survival (OS), toxicity and QoL. Thirty-nine patients with a median age of 55 (28-80) were included. The RR was 51.3 %. Median PFS and OS were 6.7 and 14.0 months, respectively. The most common adverse events (all grades) were anemia (34, 87.2 %), fatigue (29, 74.4 %), neutropenia (26, 66.7 %), nail change (19, 48.7 %) and liver dysfunction (15, 38.5 %). In QoL analysis, improvements were obtained in seven scales, whereas drops were seen in three scales. Common Grade 3/4 toxicities included anemia (28.2 %), liver dysfunction (7.7 %) and fatigue (7.7 %). This novel regimen is a promising option for AGC, showing high RR, improvement on QoL and acceptable toxicity.

Favorable effect of the combination of vinorelbine and dihydropyrimidine dehydrogenase‑inhibitory fluoropyrimidine in EGFR‑mutated lung adenocarcinoma: retrospective and in vitro studies

Although cytotoxic chemotherapy is essential in epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC), it is unclear which regimen is most effective. We retrospectively compared the efficacy of standard platinum-based chemotherapy with that of combination chemotherapy using vinorelbine (VNR) plus dihydropyrimidine dehydrogenase-inhibitory fluoropyrimidine (DIF) in EGFR-mutated lung adenocarcinomas, and we investigated a potential mechanism by which the combination chemotherapy of VNR + DIF was favorable in the treatment of EGFR-mutated lung adenocarcinoma in vitro. In our retrospective analysis, the response rate and disease control rate afforded by the VNR + DIF treatment tended to be better than those by platinum-based chemotherapy, and the progression-free survival of the 24 VNR + DIF-treated patients was significantly longer than that of the 15 platinum-based chemotherapy patients. In EGFR-mutated PC9 cells, VNR induced EGFR dephosphorylation at a clinically achievable concentration. 1BR3-LR cells, a line of fibroblast cells transfected with a mutant EGFR construct, were completely resistant to gefitinib in the medium containing 10% fetal bovine serum (FBS), whereas the sensitivity of these cells to gefitinib was increased in 0.5% FBS-containing medium. Similarly, the sensitivity of 1BR3-LR cells to VNR was increased when they were cultured in low-serum condition. In addition, sodium orthovanadate (Na₃VO₄) inhibited the EGFR dephosphorylation induced by VNR or gefitinib and suppressed the cell growth inhibition by these agents in PC9 cells. VNR and gefitinib showed synergistic cell growth inhibition in combination with 5-fluorouracil (5-FU) in PC9 cells. We propose that the EGFR dephosphorylation induced by VNR is related to cell growth inhibitory activity of VNR, and that this is one of the mechanisms of the synergistic effect of VNR + 5-FU in EGFR-mutated lung cancer cells. In conclusion, the combination chemotherapy of VNR + DIF may be a promising treatment for NSCLC patients with EGFR mutations.

Bi-weekly docetaxel and 5-fluorouracil: an effective and feasible treatment for advanced gastric cancer with poor performance status

BACKGROUND

The survival benefits from cytotoxic chemotherapy have been demonstrated in advanced gastric cancer (AGC). A large proportion of AGC patients initially present poor performance status (PS); however, most of the clinical evidence comes from trials on patients with good PS. A better-designed regimen is greatly needed for AGC patients with poor PS.

OBJECTIVE

To evaluate the efficacy and safety of a modified combination regimen with docetaxel plus 5-fluorouracil (5-FU) every two weeks as first-line treatment in AGC patients with poor PS.

METHODS

From September 2011 to December 2013, 12 patients diagnosed with AGC with Eastern Cooperative Oncology Group (ECOG) PS scores of 3 or 4 were included in this study. All the patients received docetaxel 60 mg/m(2) on Day 1, 5-FU 400 mg/m(2) intravenous (i.v.) bolus on Day 1, and a 46-hour continuous i.v. infusion of 5-FU 2400 mg/m(2) every two weeks, until disease progressed or patients experienced unacceptable toxicity or declined treatment. Detailed clinical, pathologic and survival data were all recorded.

RESULTS

Eleven out of 12 patients were assessable for responses, whereas nine cases (75%) achieved partial response, one (8.3%) achieved stabilized disease, and one (8.3%) had progressive disease. The median progression-free survival was 6.5 months (95% CI: 4.8-8.2). The median overall survival was 12.0 months (95% CI: 9.0-15.0). The most common Grade 3/4 toxicities were anemia in seven patients (58.3%). No patient experienced febrile neutropenia.

CONCLUSION

The novel modification of bi-weekly docetaxel and 5-FU is a promising treatment option for AGC with poor PS, showing great efficacy and acceptable toxicity.

Use of rodents as models of human diseases

Advances in molecular biology have significantly increased the understanding of the biology of different diseases. However, these discoveries have not yet been fully translated into improved treatments for patients with diseases such as cancers. One of the factors limiting the translation of knowledge from preclinical studies to the clinic has been the limitations of in vivo diseases models. In this brief review, we will discuss the advantages and disadvantages of rodent models that have been developed to simulate human pathologies, focusing in models that employ xenografts and genetic modification. Within the framework of genetically engineered mouse (GEM) models, we will review some of the current genetic strategies for modeling diseases in the mouse and the preclinical studies that have already been undertaken. We will also discuss how recent improvements in imaging technologies may increase the information derived from using these GEMs during early assessments of potential therapeutic pathways. Furthermore, it is interesting to note that one of the values of using a mouse model is the very rapid turnover rate of the animal, going through the process of birth to death in a very short timeframe relative to that of larger mammalian species.

Non-platinum-based chemotherapy for treatment of advanced gastric cancer: 5-fluorouracil, taxanes, and irinotecan

Despite numerous advances in treatment options, advanced gastric cancer (AGC) remains a major public health issue and the leading cause of cancer-related deaths. Cisplatin is one of the most effective broad-spectrum anticancer drugs for AGC and a doublet combination regimen of either cisplatin-based or 5-fluorouracil (5FU)-based chemotherapy is generally used for treatment of patients with AGC. However, there is still no consensus on the best regimen for treating AGC. Recently, various new chemotherapeutic agents, including oral 5FU, taxanes, and irinotecan, have been identified as improving the outcomes for AGC when used as a single agent or in combination with non-platinum chemotherapy. Nonetheless, it is still unclear whether non-platinum-based chemotherapy is a viable treatment option for patients with AGC. Accordingly, this review focuses on the efficacy and tolerability of non-platinum-based chemotherapy for patients with AGC.

Adjuvant chemotherapy with S-1 followed by docetaxel for gastric cancer and CY1P0 peritoneal metastasis after relatively curative surgery

OBJECTIVE

The aim of this study was to assess the feasibility and safety of adjuvant chemotherapy with S-1 followed by docetaxel.

PATIENTS AND METHOD

Twenty-eight patients with advanced gastric cancer underwent gastrectomy without preoperative chemotherapy. These patients were divided into 3 groups on the basis of cytologic results of peritoneal lavage (CY) and the presence of local peritoneal metastatic nodules (P): CY1-P0, CY0-P1, and CY1-P1. Oral S-1 (80 mg/m(2)/day) was administered for 3 consecutive weeks, followed by intravenous docetaxel (35 mg/m(2)) on days 29 and 43 (1 cycle). This cycle was repeated every 8 weeks. The primary endpoint was the ability to complete 6 cycles of S-1 followed by docetaxel. The secondary endpoints were safety, progression-free survival, mean survival time (MST), and overall survival (OS).

RESULTS

The subjects were 18 men and 10 women (39 to 78 years old, median age, 64 years). The extent of peritoneal metastasis was CY1-P0 in 8 patients, CY0-P1 in 14 patients, and CY1-P1 in 6 patients. Both hematologic and nonhematologic toxicities were generally mild. The completion rate of the planned 6 cycles of the protocol was 71.4% (20 of 28 patients). Median progression-free survival was 22.9 months, and the 2-year survival rate was 78.6%. The overall MST was 34.3 months, and the MST by group was 34.5 for CY1-P0, 34.3 for CY0-P1, and 19.3 months for CY1-P1. The OS in the CY1-P0 and CY0-P1 groups was significantly longer than that in the CY1-P1 group (P<0.05).

CONCLUSION

Adjuvant chemotherapy with S-1 followed by docetaxel is safe and well tolerated and has the potential to improve OS in patients with a status of CY1P0 following relatively curative resection.

Clinical development of S-1 for non-small cell lung cancer: a Japanese perspective

For more than a decade, S-1 has been investigated aggressively against non-small cell lung cancer (NSCLC) in Japan. Recently, two randomized phase III trials of S-1 combined with cisplatin (CDDP) or carboplatin (CBDCA) compared with the standard platinum doublet chemotherapy were reported. S-1 and CDDP was noninferior to CDDP and DTX in terms of overall survival (OS) (median survival time [MST] 16.1 versus 17.1 months, respectively; hazard ratio [HR] 1.013; 96.4% confidence interval [CI] 0.837-1.227). Noninferiority of S-1 and CBDCA compared with CBDCA and paclitaxel was also confirmed for OS (MST 15.2 versus 13.3 months, respectively; HR 0.928; 99.2% CI 0.671-1.283). The noninferiority design employed an upper CI limit of HR<1.322 in the former trial and HR<1.33 in the latter. S-1 combined with CDDP or CBDCA was thought to be one of the standard platinum doublet regimens in the first-line setting for patients with advanced NSCLC in Japan. Some additional interesting phase I and II studies have been published in Japan. They include studies of S-1 as first-line chemotherapy when combined with nonplatinum agents; as second-line chemotherapy; within chemoradiotherapy for locally advanced disease; and in the postoperative adjuvant setting. This review will also describe the use of S-1 for the treatment of NSCLC in these settings.

Phase I/II study of intraperitoneal docetaxel plus S-1 for the gastric cancer patients with peritoneal carcinomatosis

Purpose

We designed a phase I/II trial of intraperitoneal (IP) docetaxel plus S-1 to determine the maximum tolerated dose (MTD) and recommended dose (RD) and to evaluate its efficacy and safety in gastric cancer patients with peritoneal carcinomatosis (PC).

Methods

Patients with PC confirmed by laparoscopy or laparotomy received IP docetaxel on days 1 and 15 and S-1 (80 mg/m²) on days 1–14 every 4 weeks.

Results

In the phase I part (n = 12), each cohort received escalating doses of docetaxel (35–50 mg/m²); the MTD was determined to be 50 mg/m² and the RD was determined to be 45 mg/m². Dose-limiting toxicities included grade 3 febrile neutropenia and grade 3 diarrhea. In the phase II part (n = 27), the median number of courses was 4 (range 2–11). The 1-year overall survival (OS) rate was 70 % (95 % confidence interval 53–87 %). The overall response rate was 22 % and peritoneal cytology turned negative in 18 of 22 (81 %) patients. The most frequent grade 3/4 toxicities included anorexia (19 %), neutropenia (7 %), and leukopenia (7 %).

Conclusion

IP docetaxel plus S-1 is active and safety in gastric cancer patients with PC.

Neoadjuvant therapy with weekly docetaxel and cisplatin, 5-fluorouracil continuous infusion, and concurrent radiotherapy in patients with locally advanced esophageal cancer produced a high percentage of long-lasting pathological complete response: a phase 2 study

BACKGROUND

This phase 2 study was aimed at defining the pathological response rate of a neoadjuvant schedule including weekly docetaxel and cisplatin, continuous infusion (c.i.) of 5-fluorouracil (5-FU) and concomitant radiotherapy (RT) in untreated stage II-III adenocarcinoma and squamous cell carcinoma of mid-distal thoracic esophagus.

METHODS

The schedule consisted of a first phase of chemotherapy alone and of a second phase of concurrent chemoradiation. Doses were as follows: docetaxel 35 mg/m(2) and cisplatin 25 mg/m(2) on days 1, 8, 15, 29, 36, 43, 50, and 57 plus 5-FU c.i. (180 mg/m(2) on days 1-21 and 150 mg/m(2) on days 29-63); RT (50 Gy) started at day 29. Surgery was planned 6 to 8 weeks after the completion of chemoradiation.

RESULTS

A total of 74 patients were enrolled; pathological complete remission (pCR) was found in 47% (35 of 74) and near pCR (microfoci of tumor cells on the primary tumor without lymph nodal metastases) (pnCR) in 15% of the patients (11 of 74). Grade 3-4 neutropenia, nonhematological toxicity, and toxic deaths occurred in 13.5%, 32.4%, and 4% of the patients, respectively. Median follow-up was 55 months (range, 3-108 months). Median survival of all 74 patients was 55 months, whereas it was not reached in the pCR subset. The 3- and 5-year survival rates were, respectively, 83% and 77% for pCR, 73% and 44% for pnCR, and 21% and 14% for Residual Tumor subsets (P < .001).

CONCLUSIONS

This study shows that 1) this intensive weekly schedule produced a high pathological response rate, 2) responders had high and long-term durable survival rates.

Combination of low-dose docetaxel and standard-dose S-1 for the treatment of advanced gastric cancer: efficacy, toxicity, and potential predictive factor

AIM

The aim of this study was to evaluate the efficacy and toxicity of low dose of docetaxel in combination with standard dose of S-1 for patients with advanced or recurrent gastric cancer and to investigate whether the protein expression level of dihydropyrimidine dehydrogenase is a predictive factor of toxicities or responses.

METHODS

Between March 2010 and December 2011, 61 patients from the Department of Medical Oncology of Shanghai Zhong Shan Hospital, Fudan University, were enrolled in the study. Patients with advanced or recurrent gastric adenocarcinoma were treated with docetaxel of 40 mg/m(2) intravenously on day 1 and S-1 of 80 mg/m(2) orally on days 1-14 every 3 weeks as first-line chemotherapy. The chemotherapeutic effects were evaluated following every 3 cycles of chemotherapy using the Response Evaluation Criteria In Solid Tumors (RECIST). The serum of peripheral blood was obtained at the start of the study and at each evaluation point to analyze the protein expression level of DPD, which was estimated using an enzyme-linked immunosorbent assay. All the patients were followed-up until the time of progression, death, or the censor time, to calculate progression-free survival and overall survival (OS) time.

RESULTS

In total, 61 patients [median age 60 years (range 28-76 years)] received a total of 318 treatment cycles [median 5 (range 2-9)], and 94 cycles of single S-1 maintenance treatment. One complete response (CR) and 25 partial responses (PR) were observed, with an overall response rate of 42.6%. A total of 29 patients (47.5%) had stable disease (SD) and 6 patients (9.8%) had progressive disease (PD). The disease control rate (DCR, CR + PR + SD) was 90.2%. Median overall survival was 13.0 months [95% confidence interval (CI) 10.76-15.24 months], and median PFS was 6.0 months (95% CI 4.61-7.39 months). Progression-free survival was far longer in peritoneal metastatic patients than that in patients with other metastases (7.3 ± 2. 6 vs. 5.4 ± 2.8 months; P < 0.05); however, this was not the case for OS. Grade 3-4 neutropenia was well controlled and grade 4 non-hematologic toxicities did not occur. Baseline expression level of DPD was not associated with efficacy. Lower expression level of DPD was correlated with high grade of toxicities (P < 0.05).

CONCLUSION

This combination of standard dose of S-1 and low dose of docetaxel is effective and well tolerated in patients with advanced or recurrent gastric cancer. Peritoneal metastasis is treated more effectively by this regimen than other forms of metastases. Baseline DPD expression level in the serum is associated with toxicity, but not tumor response.

Phase I/II trial of a biweekly combination of S-1 plus docetaxel in patients with previously treated non-small cell lung cancer (KRSG-0601)

Background:

Combination of S-1, an oral fluorouracil derivative, plus docetaxel against non-small cell lung cancer (NSCLC) showed promising efficacy but clinically problematic emesis. A phase I/II study utilising a new schedule for this combination was conducted.

Methods:

A biweekly regimen of docetaxel on day 1 with oral S-1 on days 1–7 was administered to previously treated NSCLC patients. Doses of docetaxel/S-1 were escalated to 30/80, 35/80, and 40/80 mg m⁻², respectively, and its efficacy was investigated at the recommended dose below maximum tolerated dose (MTD).

Results:

In phase I study employing 13 patients, dose-limiting toxicities were febrile neutropenia and treatment delay, with the respective MTDs for docetaxel 40 mg m⁻²/S-1 80 mg m⁻². In the phase II study, 34 patients were treated with docetaxel 35 mg m⁻²/S-1 80 mg m⁻² for a median cycle of 6. The response and disease control rates were 34.3% (95% confidence interval (CI), 18.6–50.0%) and 62.9% (95% CI, 46.8–72.9%), respectively. Median progression-free survival was 150.5 days. Haematologic grade 4 toxicities were observed in neutropenia (11.8%) and thrombocytopenia (2.9%). Regarding non-haematologic toxicities, including emesis, there were no grade 3/4 side effects.

Conclusion:

Combination of 1-week administration of S-1 with biweekly docetaxel is safe and active for NSCLC.

Antitumor efficacy of sequential treatment with docetaxel and 5-fluorouracil against human oral cancer cells

Docetaxel (DOC) and 5-fluorouracil (5-FU) are important anticancer agents widely used in the treatment of a variety of cancers including oral squamous cell carcinoma (OSCC). The purpose of this study was to determine the antitumor efficacy of the sequential administration of DOC and 5-FU against OSCC cells (B88 and CAL27 cells) in vitro and in vivo. In in vitro growth inhibition assays, sequential treatment with DOC followed by 5-FU was more effective in inhibiting cancer cell growth than 5-FU followed by DOC, single treatment with DOC or 5-FU, or combined treatment with DOC and 5-FU. Furthermore, DOC followed by 5-FU significantly inhibited tumor growth in vivo compared to 5-FU followed by DOC. To understand the mechanisms underlying the enhanced growth inhibitory effect of the administration sequence, DOC followed by 5-FU, we examined the expression of 5-FU metabolic enzymes such as thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD) and orotate phosphoribosyl transferase (OPRT), which were known to regulate the antitumor effect of 5-FU, by real-time RT-PCR and western blot analysis. Downregulation of TS and DPD expression and upregulation of OPRT expression were induced by DOC treatment, suggesting that DOC enhanced the efficacy of 5-FU by altering the expression of its metabolic enzymes. These results indicate that sequential treatment with DOC followed by 5-FU could be a promising therapeutic strategy for oral cancer.

Anticancer activity of an extract from needles and twigs of Taxus cuspidata and its synergistic effect as a cocktail with 5-fluorouracil

BACKGROUND

Botanical medicines are increasingly combined with chemotherapeutics as anticancer drug cocktails. This study aimed to assess the chemotherapeutic potential of an extract of Taxus cuspidata (TC) needles and twigs produced by artificial cuttage and its co-effects as a cocktail with 5-fluorouracil (5-FU).

METHODS

Components of TC extract were identified by HPLC fingerprinting. Cytotoxicity analysis was performed by MTT assay or ATP assay. Apoptosis studies were analyzed by H & E, PI, TUNEL staining, as well as Annexin V/PI assay. Cell cycle analysis was performed by flow cytometry. 5-FU concentrations in rat plasma were determined by HPLC and the pharmacokinetic parameters were estimated using 3p87 software. Synergistic efficacy was subjected to median effect analysis with the mutually nonexclusive model using Calcusyn1 software. The significance of differences between values was estimated by using a one-way ANOVA.

RESULTS

TC extract reached inhibition rates of 70-90% in different human cancer cell lines (HL-60, BGC-823, KB, Bel-7402, and HeLa) but only 5-7% in normal mouse T/B lymphocytes, demonstrating the broad-spectrum anticancer activity and low toxicity to normal cells of TC extract in vitro. TC extract inhibited cancer cell growth by inducing apoptosis and G(2)/M cell cycle arrest. Most interestingly, TC extract and 5-FU, combined as a cocktail, synergistically inhibited the growth of cancer cells in vitro, with Combination Index values (CI) ranging from 0.90 to 0.26 at different effect levels from IC50 to IC90 in MCF-7 cells, CI ranging from 0.93 to 0.13 for IC40 to IC90 in PC-3M-1E8 cells, and CI < 1 in A549 cells. In addition, the cocktail had lower cytotoxicity in normal human cell (HEL) than 5-FU used alone. Furthermore, TC extract did not affect the pharmacokinetics of 5-FU in rats.

CONCLUSIONS

The combinational use of the TC extract with 5-FU displays strong cytotoxic synergy in cancer cells and low cytotoxicity in normal cells. These findings suggest that this cocktail may have a potential role in cancer treatment.

The roles of surgical oncologists in the new era: minimally invasive surgery for early gastric cancer and adjuvant surgery for metastatic gastric cancer

In the new era of technical development in surgery, operative devices, molecular targeting and chemotherapeutic agents, surgical oncologists have two main roles in the treatment of gastric cancer. One is to provide patients with minimally invasive surgery, including laparoscopy- or robot-assisted surgery in early gastric cancer patients, and the new concept of surgical intervention toward advanced and metastatic disease. Since recently, laparoscopy-assisted distal gastrectomy has become prevalent in Japan as a surgery which is minimally invasive for the patients and provides them with a good quality of life afterwards. However, the provision of advanced surgical techniques, including lymph node dissection and reconstruction, is more important for patient survival. The second role of surgical oncologists is to evaluate the significant values of the aggressive treatment which we term 'adjuvant surgery' for stage IV gastric cancer patients who have successfully responded to initial chemotherapy for curative intent. Stage IV gastric cancer patients are now being informed about the possibility of longer survival with the new chemotherapeutic and surgical strategic approach.

Quantitative analysis of the enzymes associated with 5-fluorouracil metabolism in prostate cancer biopsies

Orotate phosphoribosyl transferase (OPRT) is the initial enzyme of 5-FU activation, in which 5-FU is converted to 5-fluorouridinemonophosphate. Dihydropyrimidine dehydrogenase (DPD) is a degrading enzyme that catabolizes 5-FU. In this study, we investigated the expression of these enzymes in normal prostate gland (NP), hormone-sensitive prostate cancer (HSPC), and hormone-refractory prostate cancer (HRPC). The prostatic tissue specimens were obtained from patients who had undergone prostate needle biopsies without any treatments or with PSA failure after initial androgen deprivation. The tissue samples derived from formalin-fixed, paraffin-embedded (FFPE) sections were prepared by laser-capture microdissection, and from them RNA was extracted. The levels of OPRT and DPD mRNA expression were examined by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). The level of OPRT mRNA expression in the HSPC or the HRPC specimens was significantly higher than that in the NP specimens. There was a significant correlation between OPRT mRNA expression levels and the tumor pathological grade. Furthermore, the OPRT/ DPD expression ratio, a powerful predictive factor to evaluate 5-FU sensitivity, in the HRPC group was significantly higher than that in the low-grade HSPC group. Thus, the quantitative evaluation for these enzymes based on phosphorylation of 5-FU may be an effective option for some prostate cancer patients, particularly HRPC group.

A randomized phase 2 study of docetaxel and S-1 versus docetaxel and cisplatin in advanced gastric cancer with an evaluation of SPARC expression for personalized therapy

BACKGROUND

The purpose of this study was to compare 2 weekly docetaxel-based regimens as first-line treatments for advanced gastric cancer and to investigate the expression of secreted protein acidic and rich in cysteine (SPARC) and its abilities to predict treatment-related clinical outcomes.

METHODS

Patients were randomly selected to receive 3 weekly cycles of docetaxel (35 mg/m(2) on days 1 and 8) plus S-1 (35 mg/m(2) each twice daily on days 1-14) (DS), or docetaxel plus cisplatin (35 mg/m(2) each on days 1 and 8) (DC). Endpoints included overall response rate (primary), survival, toxicity, and quality of life (secondary). SPARC expression in prechemotherapy specimens of primary gastric tumors was evaluated via immunohistochemical analysis.

RESULTS

Eighty patients were enrolled in the study. Confirmed overall response rates were 46% (95% confidence interval, 30%-62%) for DS and 24% (95% confidence interval, 11%-38%) for DC via intent-to-treat analysis. Median progression-free survival was 7.3 and 4.9 months and overall survival was 16.0 and 8.3 months for DS and DC, respectively. The most common grade ≥ 3 toxicity was neutropenia. Grade ≥ 3 mucositis (18%) and hand-foot syndrome (8%) were the toxicities most associated with DS, whereas anorexia (20%) and lethargy (20%) were more common with DC. High SPARC expression was related to early progression (hazard ratio, 3.67; P = .042) and poor overall survival (hazard ratio, 2.01; P = .010) in docetaxel chemotherapy on multivariate analysis.

CONCLUSIONS

The outcomes in this study favored DS over DC for further phase 3 study. The findings suggest that split-dose weekly docetaxel alleviates hematological toxicity without compromising efficacy, and that SPARC expression may help individualize therapy in advanced gastric cancer.

Biweekly docetaxel, cisplatin, and 5-fluorouracil (DCF) chemotherapy for advanced esophageal squamous cell carcinoma: a phase I dose-escalation study

BACKGROUND AND PURPOSE

The optimal chemotherapeutic protocol for the treatment of esophageal cancer has not yet been established. A dose-escalation study of docetaxel combined with cisplatin and 5-fluorouracil (5-FU) was performed to determine the optimal dose in patients with advanced esophageal squamous cell carcinoma.

PATIENTS AND METHOD

We studied a total of 18 patients who had previously untreated thoracic esophageal squamous cell carcinoma with T4 tumors and/or metastasis. The patients received an infusion of docetaxel at different dose levels (levels 1, 2, 3: 30, 35, 40 mg/m(2), respectively) and an infusion of cisplatin (40 mg/m(2)) on days 1 and 15 plus a continuous infusion of 5-FU (400 mg/m(2)/day) on days 1-5 and 15-19.

RESULTS

Dose-limiting toxicities (DLT) included febrile neutropenia and leukopenia. DLT occurred in 2 of 6 patients at level 1, 2 and in 3 of 6 patients at level 3. The response rate was 88.9%, including a complete response rate of 33.3%.

CONCLUSIONS

To minimize toxicity and maximize dose intensity, we elected to investigate a biweekly regimen. The maximum tolerated dose was level 3, and the recommended dose was determined to be docetaxel 35 mg/m(2) with cisplatin 40 mg/m(2) plus 5-FU 400 mg/m(2), administered biweekly. This regimen was tolerable and highly active. A phase II study has been started.

Effect of leucovorin on the antitumor efficacy of the 5-FU prodrug, tegafur-uracil, in human colorectal cancer xenografts with various expression levels of thymidylate synthase

The combination of oral tegafur-uracil (UFT) with leucovorin (LV) is used to treat patients with stage II to III colon cancer based on the results of postoperative randomized studies in which UFT/LV treatment showed an equivalent efficacy to intravenous 5-FU plus LV therapy. However, whether the addition of LV to UFT can elevate the antitumor activity of UFT in colorectal tumors with high expression levels of thymidylate synthase (TS), which affects 5-FU efficacy, remains to be clarified. This study investigated the effect of LV on the antitumor activity of UFT and/or 5-FU prodrugs in low folate diet-fed nude mice using human colorectal cancer xenografts with various expression levels of TS. The addition of LV to UFT resulted in a 55-79% inhibition of tumor growth among 11 types of colorectal tumor xenograft, whereas UFT alone showed 23-67% antitumor activity. Although there was an inverse relationship between the antitumor effect of UFT alone and UFT plus LV and tumoral TS activity, UFT plus LV appeared to have a more potent antitumor effect than UFT alone on colorectal tumors such as Co-3 and KM12C/5-FU with high expression levels of TS. This finding was confirmed by the significant positive correlation between the relative inhibition ratio of UFT/LV to UFT alone and TS levels in tumors. To investigate the reason for the higher efficacy of UFT/LV on colorectal cancer xenografts with high TS activity, intratumoral levels of reduced folates and a ternary complex of TS after oral UFT with or without LV were measured using Co-3 xenografts. Elevated levels of reduced folates and an increased ternary complex of TS in LV-treated tumors were noted. Our results indicate that a combined therapy of UFT with LV may contribute to the treatment of colorectal cancer patients with low and high expression levels of tumoral TS by increased formation of the ternary complex of TS leading to potentiated antitumor efficacy of UFT.

Phase II study of biweekly docetaxel and S-1 combination chemotherapy as first-line treatment for advanced gastric cancer

PURPOSE

We evaluated the efficacy and toxicity of biweekly S-1 and docetaxel combination therapy in patients with advanced gastric cancer.

METHODS

Patients with histologically proven, unresectable advanced or recurrent gastric cancer, a performance status (PS) of 0-2 and no prior chemotherapy history were eligible for inclusion (n = 45). Patients received a total of 215 treatment courses (median, 4; range, 2-12) of S-1 oral administration twice daily for 1 week followed by a drug-free interval of 1 week. Docetaxel (40 mg/m(2)) was administered intravenously on days 1 and 15.

RESULTS

We observed 25 partial responses (55.6%) and one complete response (2.2%), resulting in an overall response rate of 57.8%. Twenty-four patients (53.3%) received second-line chemotherapy. Five patients (11.1%) underwent R0 gastrectomy during the course of the study. The median overall survival time was 15.3 months, the median time to progression was 6.9 months, and the median duration of response in 26 patients was 8.0 months. Neutropenia was the most frequently observed (40.4%) haematological toxicity at grades 3 and 4 and leucopenia was the second most common (29.8%). There were no treatment-related deaths.

CONCLUSIONS

S-1 plus docetaxel combination therapy in an outpatient setting provided promising activity with acceptable adverse toxicities.

Preliminary trial of adjuvant surgery for advanced gastric cancer

In patients with stage IV gastric cancer, systemic chemotherapy is the key treatment. Combination chemotherapy (cis-diamminedichloride platinum plus S-1 and docetaxel plus S-1) results in long-term survival in clinical practice. In selected cases, additional (adjuvant) surgery may result in further long-term survival. This study aimed to evaluate the efficacy of adjuvant surgery following the response to chemotherapy for advanced gastric cancer. Based on response to chemotherapy, the indications for adjuvant surgery (surgery after the response to chemotherapy) are that resection is expected to be curative rather than palliative, provided that no other distant metastases occur. The study included 20 advanced gastric cancer patients who had undergone gastrectomies after the response to the combination chemotherapy of docetaxel and S-1, between September 2003 and December 2008 at Hiroshima University Hospital. At a median follow-up of 980 days, the median overall survival was 855 days. A 2- and 3-year survival was observed in 80 and 54.9% of patients, respectively, following macroscopic curative surgery. In the palliative group, the median overall survival was 510 days, but a 3-year survival was not observed. In the partial response group, the median overall survival was 865 days and a 3-year survival was observed in 37% of patients. One-year survival was not observed in the stable disease group. The patient survival in the partial response group was statistically more prolonged than in the stable disease group. The median overall survival in patients with liver metastasis was 865 days, while that in patients with peritoneal dissemination was 510 days. In conclusion, adjuvant surgery may be effective in gastric cancer patients diagnosed as stage IV by means of liver or distant lymph node metastasis, except in cases of peritoneal dissemination.

Phase II study of S-1, a novel oral fluoropyrimidine, and biweekly administration of docetaxel for previously treated advanced non-small-cell lung cancer

Purpose

We examined the safety and efficacy of the combination of S-1 and biweekly docetaxel in patients with previously treated advanced non-small-cell lung cancer (NSCLC).

Methods

Patients with previously treated advanced NSCLC were eligible if they had a performance status of 2 or less, were 80 years or younger, and had adequate organ function. Forty-nine patients (38 men and 11 women; median age, 66 years; range 43–79 years) were enrolled. Patients were treated with the combination of 80 mg/m² per day of S-1 for 14 consecutive days and 35 mg/m² of docetaxel on days 1 and 15 every 4 weeks.

Results

The overall response rate was 16.3% (95% confidence interval, 7.6–30.5%). The disease-control rate was 49.0% (95% confidence interval, 34.4–63.7%). The median survival time after this treatment was 9 months (range 1–22 months). The median progression-free survival time was 3 months (range 1–11 months). Response rates and survival times did not differ significantly according to the histological type. Grade 3–5 toxicities included neutropenia in 51.0% of patients, thrombocytopenia in 2.0%, anemia in 20.4%, infection in 24.5%, anorexia in 12.2%, diarrhea in 14.3%, nausea in 6.1%, and dehydration in 4.2%. There was 1 treatment-related death due to severe anorexia, stomatitis, diarrhea, and, as consequence, dehydration.

Conclusions

The combination of S-1 and biweekly docetaxel is an acceptable therapeutic option in patients with previously treated advanced NSCLC regardless of the histological type.

Combination therapy with docetaxel and S-1 as a first-line treatment in patients with advanced or recurrent gastric cancer: a retrospective analysis

BACKGROUND

We performed a single-institution retrospective study to evaluate the efficacy and toxicities of combination therapy with docetaxel and S-1 in patients with advanced or recurrent gastric cancer.

METHODS

Eighty-six patients with advanced or recurrent gastric cancer were enrolled. Patients received docetaxel, 40 mg/m2, on day 1 and oral S-1, 80 mg/m2/day, on days 1 to 14 every 3 weeks.

RESULTS

All 84 patients were assessable for response. The overall response rate was 52.4% (44/84) and the disease control rate was 96.4% (81/84). Median time to progression (TTP) and overall survival (OS) were 6.5 (95% CI, 4.8-8.1 months) and 15.1 months (95% CI, 11.7-18.5 months), respectively. The major toxicities were neutropenia, leukopenia, alopecia and anorexia. Grade 3 or 4 hematologic toxicities included neutropenia in 31 patients (36.0%), leukopenia in 27 (31.7%), febrile neutropenia in four (4.7%), and anemia in one (1.2%). Other grade 3 toxicities included anorexia in five patients (5.8%), and stomatitis, diarrhea and nausea in one each (1.2%). There was one treatment-related death (1.2%).

CONCLUSION

The combination of docetaxel and S-1 had good clinical activity with acceptable toxicity in patients with advanced or recurrent gastric cancer.

Rapamycin enhances chemotherapy-induced cytotoxicity by inhibiting the expressions of TS and ERK in gastric cancer cells

We have previously reported the synergistic cytotoxic effects of Docetaxel (TXT) and S-1 in gastric cancer in vitro and in vivo, and the combination regimen is now under phase III clinical trail. In this study, to elucidate whether the rapamycin, the inhibitor of the mTOR (mammalian target of rapamaycin), can enhance the potentiation of TXT and 5-fluorouracil (5-Fu) in gastric carcinoma cells. Rapamycin inhibited the growth of TMK-1, MKN-28, MKN-45 and MKN-74 cell lines by MTT assay, and it demonstrated the cytostatic effects as G1 arrest shown by flowcytometry. However, the cytotoxic effects of 5-Fu, TXT and cisplatin were enhanced by 2 to 4 times with the concomitant administration of rapamycin. To clarify the mechanism of the potentiation, the expression changes of the enzymes relating DNA metabolism and cell growth signal transduction pathways were examined by western blot analysis. Interestingly, the expression of thymidilate synthase was markedly decreased by the administration of rapamycin in TMK-1 cells in a time- and dose-dependent manner. Moreover, rapamycin decreased the phosphorylation of 4E-BP1, the phosphorylation of ERK1/2 and enhanced the phosphorylation of c-Jun NH2-terminal kinase, and the activation of caspase of apoptotic pathways in combination with TXT. These results strongly indicate that the mTOR inhibitor can enhance the potentiation of TXT and 5-Fu or S-1 and can serve as a new therapeutic tool for advanced and recurrent gastric cancer patients.

Docetaxel: its role in current and future treatments for advanced gastric cancer

A globally accepted standard chemotherapy remains undetermined in gastric cancer, but the recent introduction of active "new-generation agents" such as taxanes, irinotecan (CPT-11), oxaliplatin, S-1, and capecitabine, offers hope for markedly improving patient outcomes. Docetaxel, as well as the other new-generation agents, plays a key role in the development of the new-era chemotherapy, and the incorporation of taxanes has provided several regimens, such as docetaxel/cisplatin/5-fluorouracil (5-FU) (DCF), that could become standard treatment. The DCF regimen is now regarded as a standard treatment option in advanced gastric cancer in selected patients in good condition. Many institutions and cooperative groups continue to study a variety of docetaxel-based combinations with "new-generation cytotoxic agents" in various treatment settings, and recent attention has been focused on the incorporation of biological agents, such as cetuximab, bevacizumab, everolimus, and sunitinib, into docetaxel-containing combinations as another innovative approach. The ongoing clinical trials of a number of new regimens will clarify their clinical benefits in gastric cancer treatment. Along with the development of more active docetaxel combination regimens, the identification of predictive biomarkers for each regimen has been intensively studied recently. This review focuses on docetaxel as a key agent in gastric cancer chemotherapy, and discusses the role of this taxane in current and future treatments for advanced gastric cancer.

Addition of S-1 to the epidermal growth factor receptor inhibitor gefitinib overcomes gefitinib resistance in non-small cell lung cancer cell lines with MET amplification

PURPOSE

Most non-small cell lung cancer (NSCLC) tumors with activating mutations in the epidermal growth factor receptor (EGFR) are initially responsive to EGFR tyrosine kinase inhibitors (EGFR-TKI) such as gefitinib and erlotinib, but they almost invariably develop resistance to these drugs. A secondary mutation in EGFR (T790M) and amplification of the MET proto-oncogene have been identified as mechanisms of such acquired resistance to EGFR-TKIs. We have now investigated whether addition of the oral fluoropyrimidine derivative S-1 to gefitinib might overcome gefitinib resistance in NSCLC cell lines.

EXPERIMENTAL DESIGN

The effects of gefitinib on EGFR signaling and on the expression both of thymidylate synthase and of the transcription factor E2F-1 in gefitinib-resistant NSCLC cells were examined by immunoblot analysis. The effects of S-1 (or 5-fluorouracil) and gefitinib on the growth of NSCLC cells were examined in vitro as well as in nude mice.

RESULTS

Gefitinib induced down-regulation of thymidylate synthase and E2F-1 in gefitinib-resistant NSCLC cells with MET amplification but not in those harboring the T790M mutation of EGFR. The combination of 5-fluorouracil and gefitinib synergistically inhibited the proliferation of cells with MET amplification, but not that of those with the T790M mutation of EGFR, in vitro. Similarly, the combination of S-1 and gefitinib synergistically inhibited the growth only of NSCLC xenografts with MET amplification.

CONCLUSIONS

Our results suggest that the addition of S-1 to EGFR-TKIs is a promising strategy to overcome EGFR-TKI resistance in NSCLC with MET amplification.