Induction of thymidine phosphorylase expression and enhancement of efficacy of capecitabine or 5'-deoxy-5-fluorouridine by cyclophosphamide in mammary tumor models

Adjuvant Capecitabine for Early Breast Cancer: 15-Year Overall Survival Results From a Randomized Trial

PURPOSE

Few data are available regarding the influence of adjuvant capecitabine on long-term survival of patients with early breast cancer.

METHODS

The Finland Capecitabine Trial (FinXX) is a randomized, open-label, multicenter trial that evaluates integration of capecitabine to an adjuvant chemotherapy regimen containing a taxane and an anthracycline for the treatment of early breast cancer. Between January 27, 2004, and May 29, 2007, 1,500 patients with axillary node-positive or high-risk node-negative early breast cancer were accrued. The patients were randomly allocated to either TX-CEX, consisting of three cycles of docetaxel (T) plus capecitabine (X) followed by three cycles of cyclophosphamide, epirubicin, and capecitabine (CEX, 753 patients), or to T-CEF, consisting of three cycles of docetaxel followed by three cycles of cyclophosphamide, epirubicin, and fluorouracil (CEF, 747 patients). We performed a protocol-scheduled analysis of overall survival on the basis of approximately 15-year follow-up of the patients.

RESULTS

The data collection was locked on December 31, 2020. By this date, the median follow-up time of the patients alive was 15.3 years (interquartile range, 14.5-16.1 years) in the TX-CEX group and 15.4 years (interquartile range, 14.8-16.0 years) in the T-CEF group. Patients assigned to TX-CEX survived longer than those assigned to T-CEF (hazard ratio 0.81; 95% CI, 0.66 to 0.99; P = .037). The 15-year survival rate was 77.6% in the TX-CEX group and 73.3% in the T-CEF group. In exploratory subgroup analyses, patients with estrogen receptor-negative cancer and those with triple-negative cancer treated with TX-CEX tended to live longer than those treated with T-CEF.

CONCLUSION

Addition of capecitabine to a chemotherapy regimen that contained docetaxel, epirubicin, and cyclophosphamide prolonged the survival of patients with early breast cancer.

Fixed dose combination of capecitabine and cyclophosphamide in metastatic breast cancer: Results from THE ENCLOSE phase 2/3 randomized multicenter study

Aim

To evaluate pharmacokinetics, efficacy and safety of fixed-dose combination (FDC) of oral capecitabine + cyclophosphamide in metastatic breast cancer (MBC) patients progressing after anthracycline and/or taxane chemotherapy.

Methods

In this prospective, adaptive, phase-2/3, open-label study (CTRI/2014/12/005234), patients were randomized (1:1:1) to three FDC doses (doses/day: D1, capecitabine + cyclophosphamide 1400 mg + 60 mg; D2, 1800 mg + 80 mg; D3, 2200 mg + 100 mg) for 14 days, in 21-day cycles. In Part-I, multiple-dose pharmacokinetics and optimal dose(s) were evaluated with futility analysis. Group(s) with <3 responders based on best overall response rate (BOR, complete response [CR]+partial response [PR]), were discontinued. Efficacy (BOR, disease control rates [DCR; CR + PR + stable disease]) and safety of optimal dose(s) were evaluated in Part-II.

Results

Of 66 patients (n = 22/group) in Part-I, pharmacokinetics (D1 = 7/22, D2 = 9/22, D3 = 8/22) showed dose-proportionality for cyclophosphamide and greater than dose-proportionality for capecitabine. Modified intent-to-treat (mITT) analysis showed BOR of 7.14% (1/14) in D1 (discontinued), and 22.22% (4/18) each in D2 and D3, respectively. In Part-II, 50 additional patients were randomized in D2 and D3 (n = 144; total 72 [22 + 50] patients/group). mITT analysis in D2 (n = 54) and D3 (n = 58) showed BOR of 29.63% (16/54, 95%CI: 17.45–41.81%) and 22.41% (13/58, 95%CI: 11.68–33.15%), respectively. DCR in D2 and D3 were 87.04% (47/54, 95%CI: 78.08–96.00%) and 82.76% (48/58; 95%CI: 73.04–92.48%) after 3 and 57.41% (31/54; 95%CI: 52.41–79.50%) and 50.00% (29/58; 95%CI: 40.40–67.00%), after 6-cycles, respectively. Hand-foot syndrome (16.67%), vomiting (9.72%) in D2, and hand-foot syndrome (18.06%), asthenia (15.28%) in D3 were most-common adverse events.

Conclusion

FDC of capecitabine + cyclophosphamide (1800 + 80 mg/day) showed high disease control rates and good safety profile in MBC patients.

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Oral fixed dose combination (FDC) of capecitabine + cyclophosphamide developed.

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FDC showed high efficacy and good safety profiles.

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Effective in MBC patients progressing post anthracycline and/or taxane exposure.

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Oral FDC formulation may reduce pill burden and improve patient compliance.

Capecitabine + Epirubicin + Cyclophosphamide Combination Therapy (CEX Therapy) as Neoadjuvant Chemotherapy for HER-2-Negative Breast Cancer: A Retrospective, Single-Center Study

BACKGROUND

We modified and administered capecitabine + epirubicin + cyclophosphamide combination therapy (CEX) as neoadjuvant chemotherapy (NAC) for HER-2-negative breast cancer and retrospectively analyzed its effectiveness and tolerability at our center.

METHODS

The inclusion criteria were presence of breast cancer negative for HER-2 and positive lymph node metastasis, or negative lymph node metastasis when tumor diameter was 20 mm or greater without distant metastasis. Additional inclusion criteria were a performance status of 0 or 1, an EF >60%, and an age of 75 years or less. Clinical outcomes were evaluated after 4 courses of epirubicin 80 mg/m2, cyclophosphamide 500 mg/m2 (administered every 3 weeks), and capecitabine 1,500 mg/m2 (administered for 2 weeks and withdrawn for 1 week).

RESULTS

A clinical benefit was noted in all 18 patients who received CEX as neoadjuvant chemotherapy during the period from 2009 through 2013. The clinical response rate was 83.3% (15/18), and the clinical complete response rate was 50%. Aesthetic outcomes of breast-conserving surgery were positive in all patients. Among patients with satisfactory outcomes, 33.3% had a pathologic complete response (triple-negative: 6, luminal: 0) and 68.8% were n0 (triple-negative: 8, luminal: 3). All patients with a pathologic complete response are presently alive, free of recurrence, and currently undergoing follow-up. Adverse events were classified as grade 2 or lower in all patients.

CONCLUSIONS

CEX therapy administered as neoadjuvant chemotherapy could be useful for individualized treatment. In particular, this regimen was effective for triple-negative breast cancer.

Severe Hemorrhagic Cystitis Caused by Cyclophosphamide and Capecitabine Therapy in Breast Cancer Patients: Two Case Reports and Literature Review

Combined oral cyclophosphamide and capecitabine (XC) chemotherapy is used for metastatic breast cancer (MBC) patients. We report herein two MBC patients who developed severe hemorrhagic cystitis after XC therapy. Case 1: A 67-year-old woman with MBC had received XC therapy for 2.5 years. After a sudden onset of lower abdominal pain and gross hematuria, cystoscopy revealed a urinary bladder mucosa showing diffuse dilation of the capillaries and a large blood clot. A total dose of 60.8 g cyclophosphamide had been given and the XC regimen was discontinued immediately. The patient experienced frequent episodes of bladder tamponade over 18 months and underwent continuous bladder irrigation and cystoscopic fulguration. Hyperbaric oxygen therapy (HBOT) provided only temporary relief and the patient subsequently developed hemorrhagic shock. A bilateral ureterostomy was eventually performed. Case 2: A 65-year-old woman with MBC was given XC for 3 years, but this was discontinued after she developed new lung lesions. The patient was given a total dose of 78.4 g of cyclophosphamide. A month later, the patient complained of intermittent gross hematuria, which progressed to persistent macroscopic hematuria for 1 week. She underwent continuous bladder irrigation with saline, without an improvement in her bladder tamponade. Subsequently, the bleeding ceased completely after HBOT. Some MBC cases can be controlled for a long time with XC therapy. For those cases, we need to realize that severe hemorrhagic cystitis may occur. Even at a low dose, requires testing periodically for occult blood in the urine to detect the early stages of cystitis.

Thymidine phosphorylase: A potential new target for treating cardiovascular disease

We recently found that thymidine phosphorylase (TYMP), also known as platelet-derived endothelial cell growth factor, plays an important role in platelet activation in vitro and thrombosis in vivo by participating in multiple signaling pathways. Platelets are a major source of TYMP. Since platelet-mediated clot formation is a key event in several fatal diseases, such as myocardial infarction, stroke and pulmonary embolism, understanding TYMP in depth may lead to uncovering novel mechanisms in the development of cardiovascular diseases. Targeting TYMP may become a novel therapeutic for cardiovascular disorders. In this review article, we summarize the discovery of TYMP and the potential molecular mechanisms of TYMP involved in the development of various diseases, especially cardiovascular diseases. We also offer insights regarding future studies exploring the role of TYMP in the development of cardiovascular disease as well as in therapy.

Adjuvant Capecitabine in Combination With Docetaxel, Epirubicin, and Cyclophosphamide for Early Breast Cancer: The Randomized Clinical FinXX Trial

Importance

Capecitabine is not considered a standard agent in the adjuvant treatment of early breast cancer. The results of this study suggest that addition of adjuvant capecitabine to a regimen that contains docetaxel, epirubicin, and cyclophosphamide improves survival outcomes of patients with triple-negative breast cancer (TNBC).

Objective

To investigate the effect of capecitabine on long-term survival outcomes of patients with early breast cancer, particularly in subgroups defined by cancer estrogen receptor (ER) and progesterone receptor (PR) content, and HER2 content (human epidermal growth factor receptor 2).

Design, Setting, and Participants

This is an exploratory analysis of the multicenter FinXX randomized clinical trial that accrued 1500 women in Finland and Sweden between January 27, 2004, and May 29, 2007. About half received 3 cycles of docetaxel followed by 3 cycles of cyclophosphamide, epirubicin, and fluorouracil (T+CEF), while the other half received 3 cycles of docetaxel plus capecitabine followed by 3 cycles of cyclophosphamide, epirubicin, and capecitabine (TX+CEX). Data analysis took place between January 27, 2004, and December 31, 2015.

Main Outcomes and Measures

Recurrence-free survival (RFS).

Results

Following random allocation, 747 women received T+CEF, and 753 women received TX+CEX. Five patients were excluded from the intention-to-treat population (3 had overt distant metastases at the time of randomization; 2 withdrew consent). The median age of the remaining 1495 patients was 53 years at the time of study entry; 157 (11%) had axillary node-negative disease; 1142 (76%) had ER-positive cancer; and 282 (19%) had HER2-positive cancer. The median follow-up time after random allocation was 10.3 years. There was no significant difference in RFS or overall survival between the groups (hazard ratio [HR], 0.88; 95% CI, 0.71-1.08; P = .23; and HR, 0.84, 95% CI, 0.66-1.07; P = .15; respectively). Breast cancer-specific survival tended to favor the capecitabine group (HR, 0.79; 95% CI, 0.60-1.04; P = .10). When RFS and survival of the patients were compared within the subgroups defined by cancer steroid hormone receptor status (ER and/or PR positive vs ER and PR negative) and HER2 status (positive vs negative), TX+CEX was more effective than T+CEF in the subset of patients with TNBC (HR, 0.53; 95% CI, 0.31-0.92; P = .02; and HR, 0.55, 95% CI, 0.31-0.96; P = .03; respectively).

Conclusions and Relevance

Capecitabine administration with docetaxel, epirubicin, and cyclophosphamide did not prolong RFS or survival compared with a regimen that contained only standard agents. Patients with TNBC had favorable survival outcomes when treated with the capecitabine-containing regimen in an exploratory subgroup analysis.

Trial Registration

clinicaltrials.gov Identifier: NCT00114816.

Valproic acid potentiates the anticancer activity of capecitabine in vitro and in vivo in breast cancer models via induction of thymidine phosphorylase expression

The prognosis of patients with metastatic breast cancer remains poor, and thus novel therapeutic approaches are needed. Capecitabine, which is commonly used for metastatic breast cancer in different settings, is an inactive prodrug that takes advantage of elevated levels of thymidine phosphorylase (TP), a key enzyme that is required for its conversion to 5-fluororacil, in tumors. We demonstrated that histone deacetylase inhibitors (HDACi), including low anticonvulsant dosage of VPA, induced the dose- and time-dependent up-regulation of TP transcript and protein expression in breast cancer cells, but not in the non-tumorigenic breast MCF-10A cell line. Through the use of siRNA or isoform-specific HDACi, we demonstrated that HDAC3 is the main isoform whose inhibition is involved in the modulation of TP. The combined treatment with capecitabine and HDACi, including valproic acid (VPA), resulted in synergistic/additive antiproliferative and pro-apoptotic effects in breast cancer cells but not in TP-knockout cells, both in vitro and in vivo, highlighting the crucial role of TP in the synergism observed. Overall, this study suggests that the combination of HDACi (e.g., VPA) and capecitabine is an innovative antitumor strategy that warrants further clinical evaluation for the treatment of metastatic breast cancer.

Capecitabine: a novel, orally administered, tumour-activated treatment for breast cancer

Objective. To provide a comprehensive review of the preclinical and clinical pharmacology and toxicology of the fluoropyrimidine, capecitabine, with particular reference to its use in metastatic breast cancer.

Data Sources. A MEDLINE search was conducted using the term ‘capecitabine’ for the period 1995 -2001. The reference lists from retrieved articles were reviewed and other relevant papers identified. The abstract books from the annual meetings of the American Society of Clinical and Oncology and the European Society of Medical Oncology were also reviewed.

Data Extraction. The aim of the review was to be comprehensive and descriptive. All studies containing information deemed to be of interest were reviewed by the author; none was excluded on grounds of quality.

Data Summary. Capecitabine is a prodrug of the widely used cytotoxic agent 5-fluorouracil (5-FU). Unlike 5-FU, it is extensively and reliably absorbed after oral administration and does not require folinate (FA) potentiation. The activation of capecitabine is a three-step enzymatic process. The final activating enzyme - thymidine phosphorylase - is found in unusually high concentrations in many solid tumours including breast cancers, resulting in preferential delivery of 5-FU to tumour tissues, and suggesting a greater potential for selective cytotoxicity than is seen with 5-FU.

Capecitabine has been examined both alone and in combination with a variety of cytotoxic drugs in the treatment of metastatic breast cancer. To date, clinical evidence supports the use of capecitabine monotherapy in patients relapsing after prior treatment with anthracyclines and taxanes and in combination with docetaxel in patients failing anthracycline treatment.

Data from phase II studies indicate that in the first of these situations, capecitabine elicits a response in about one-fifth of patients and that responses are associated with symptomatic relief and extended survival. In the latter situation, a phase III study has shown that the combination of docetaxel and capecitabine elicits superior response rates, remission durations, and overall survival compared with the taxane alone and with no clinically important increase in toxicity.

Used alone or in combination, the most notable adverse effect associated with capecitabine is palmar-plantar erythrodysasthesia (hand -foot syndrome), a characteristic complex of reddening, dryness, and soreness of the palms of the hands and soles of the feet, which is rarely disabling and readily managed by treatment interruption and dose reduction.

Doxifluridine-conjugated 2-5A analog shows strong RNase L activation ability and tumor suppressive effect

RNase L is activated by 2',5'-oligoadenylates (2-5A) at subnanomolar levels to cleave single-stranded RNA. We previously reported the hypothesis that the introduction of an 8-methyladenosine residue at the 2'-terminus of the 2-5A tetramer shifts the 2-5A binding site of RNase L. In this study, we synthesized various 5'-modified 2-5A analogs with 8-methyladenosine at the 2'-terminus. The doxifluridine-conjugated 8-methyladenosine-substituted 2-5A analog was significantly more effective as an activator of RNase L than the parent 5'-monophophorylated 2-5A tetramer and showed a tumor suppressive effect against human cervical cancer cells.

Therapeutic potential of TAS-102 in the treatment of gastrointestinal malignancies

Fluoropyrimidines form the mainstay in treatment of gastrointestinal malignancies. For decades 5-fluorouracil (5FU), was the major fluoropyrimidine. Currently it is usually given in a combination with leucovorin and oxaliplatin, i.e. FOLFOX, or irinotecan, i.e. FOLFIRI, or all three, i.e. FOLFIRINOX, but gradually it has been replaced by oral fluoropyrimidine prodrug formulations, such as tegafur-uracil and S-1 (both contain ftorafur), and capecitabine (Xeloda®). Novel drugs such as the antivascular endothelial growth factor antibody, bevacizumab, and the anti-epidermal growth factor receptor antibody, cetuximab, are often combined with one of these treatment options. However, when resistance emerged, no alternatives were available. TAS-102, a combination of trifluorothymidine and the thymidine phosphorylase inhibitor TPI in a 1:0.5 ratio, is a novel oral formulation, which is active in 5FU-resistant models, both in vitro and in xenograft models. In addition to inhibition of thymidylate synthase, the major mechanism of action of classical fluoropyrimidines, TAS-102's major mechanism of action is incorporation into DNA, thereby causing DNA damage. TAS-102 also follows an alternative activation pathway via thymidine kinase, and is not a substrate for dihydropyrimidine dehydrogenase. All together this explains the efficacy in 5FU-resistant models. In early clinical studies, the twice-daily schedule (5 days on, 2 days rest) for 2 weeks every 4 weeks, led to a significant disease control rate in various malignancies. This schedule showed consistent activity in two randomized trials on fluoropyrimidine refractory colorectal cancer patients, reflected by an increase of 2-3 months in overall survival in the TAS-102 group compared with placebo. Considering the impressive preclinical potential of various combinations TAS-102 has the promise to become an alternative for 5FU-resistant cancer.

Superior antitumor activity of trastuzumab combined with capecitabine plus oxaliplatin in a human epidermal growth factor receptor 2-positive human gastric cancer xenograft model

In the treatment of human epidermal growth factor receptor 2 (HER2)-positive advanced gastric or gastroesophageal junction cancer, it has been reported that the combination of trastuzumab with capecitabine plus cisplatin, or with 5-fluorouracil (5-FU) plus cisplatin, significantly increased overall survival compared with chemotherapy alone (ToGA trial). In addition, adjuvant therapy with capecitabine plus oxaliplatin (XELOX) improved the survival of patients who received curative D2 gastrectomy (CLASSIC trial). However, the efficacy of the combination of trastuzumab with XELOX for patients with HER2-positive gastric cancer remains unknown. The aim of this study, was to investigate the efficacy of the combination of trastuzumab with XELOX in a HER2-positive human gastric cancer xenograft model. Combination treatment with these three agents (trastuzumab 20 mg/kg, capecitabine 359 mg/kg and oxaliplatin 10 mg/kg), was found to exhibit a significantly stronger antitumor activity in NCI-N87 xenografts compared with either trastuzumab or XELOX alone. In this model, treatment with trastuzumab alone or trastuzumab plus oxaliplatin enhanced the expression of thymidine phosphorylase (TP), a key enzyme in the generation of 5-FU from capecitabine in tumor tissues. In in vitro experiments, trastuzumab induced TP mRNA expression in NCI-N87 cells. In addition, NCI-N87 cells co-cultured with the natural killer (NK) cell line CD16(158V)/NK-92 exhibited increased expression of TP mRNA. When NCI-N87 cells were cultured with CD16(158V)/NK-92 cells in the presence of trastuzumab, the mRNA expression of cytokines reported to have the ability to induce TP was upregulated in tumor cells. Furthermore, a medium conditioned by CD16(158V)/NK-92 cells also upregulated the expression of TP mRNA in NCI-N87 cells. These results suggest that trastuzumab promotes TP expression, either by acting directly on NCI-N87 cells, or indirectly via a mechanism that includes trastuzumab-mediated interactions between NK and NCI-N87 cells. Therefore, the combination of trastuzumab with XELOX may be a potent therapy for HER2-positive gastric cancer.

A phase II study of metronomic paclitaxel/cyclophosphamide/capecitabine followed by 5-fluorouracil/epirubicin/cyclophosphamide as preoperative chemotherapy for triple-negative or low hormone receptor expressing/HER2-negative primary breast cancer

PURPOSE

Better treatments for triple-negative breast cancer (TNBC) are needed. To address this need, we studied the effects of preoperative metronomic paclitaxel/cyclophosphamide/capecitabine (mPCX) followed by 5-fluorouracil (FU)/epirubicin/cyclophosphamide (FEC) as preoperative chemotherapy in TNBC patients.

METHODS

Forty primary TNBC patients received four cycles of metronomic paclitaxel (80 mg/m(2) on Days 1, 8, and 15), cyclophosphamide (50 mg/body daily), and capecitabine (1,200 mg/m(2) daily), followed by four cycles of 5-FU (500 mg/m(2)), epirubicin (100 mg/m(2)), and cyclophosphamide (500 mg/m(2)) every 3 weeks. The primary end point was the pathological complete response (pCR) rate.

RESULTS

Forty patients formed the intent-to-treat population. The median dose intensities of paclitaxel, cyclophosphamide, and capecitabine were 89.7, 92.1, and 89.8%, respectively. Five patients discontinued mPCX and two discontinued FEC, primarily because of adverse events, resulting in a per-protocol population (PPS) of 33 patients. The pCR (ypT0/Tis ypN0) rate was 47.5% (19/40) in the intent-to-treat population and 54.5% (18/33) in the PPS. The clinical response rates were 36/40 (90.0%) and 31/33 (93.9%) in the intent-to-treat and PPS, respectively. The breast conservation rate was 72.7% (24/33), and 5/13 patients underwent partial resection instead of pre-planned total mastectomy. Grade 3-4 adverse events included neutropenia (35%), leukopenia (25%), and hand-foot syndrome (8%).

CONCLUSIONS

Metronomic PCX followed by FEC chemotherapy was associated with a high pCR rate and low toxicity in TNBC patients. Further studies of this regimen in larger numbers of patients are warranted.

Thymidine phosphorylase is both a therapeutic and a suicide gene in a murine model of mitochondrial neurogastrointestinal encephalomyopathy

Suicide gene therapy (SGT) is a promising strategy for treating cancer. In this work, we show that thymidine phosphorylase (TP) deficiency, the underlying genetic defect in mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), presents an opportunity to apply SGT using capecitabine, a commonly used prodrug that is converted into 5-fluorouracil by TP. Using an immortalised B-lymphoblastoid cell line from a patient with MNGIE, the tumourigenic EL-4 cell line, lentiviral vectors encoding TP and a double knockout (Tymp(-/-)Upp1(-/-)) murine model, we found that EL-4 cell-derived TP(+) tumours were exquisitely sensitive to capecitabine and generated a significant local bystander effect. In addition, we detected a spontaneous cytolytic immune response in a significant fraction of the animals surviving more than 20 days after termination of the therapy. These data indicate that, in individuals lacking TP expression, TP is a highly specific suicide gene, which can be used to treat tumours that could hypothetically arise in MNGIE patients undergoing gene therapy, as these tumours will likely originate from the gene-modified cells and will be selectively targeted by capecitabine. These observations have important implications for gene therapy for MNGIE.

A polymorphism in the TYMP gene is associated with the outcome of HLA-identical sibling allogeneic stem cell transplantation

Thymidine phosphorylase (TYMP), an enzyme involved in nucleotide synthesis, has been implicated in critical biological processes such as DNA replication, protection against mutations, and tissue repair. In this work, we retrospectively evaluated the influence of a polymorphism in the TYMP gene (rs112723255; G/A) upon the outcome of 448 patients subjected to allogeneic stem cell transplantation (allo-SCT) from an human leukocyte antigen (HLA)-identical sibling donor. The TYMP genotype of patients correlated with overall survival-carriers of the minor allele (A) being at an increased risk of dying after transplantation (hazard ratio, HR = 1.9; P = 0.004). This effect was mostly due to differences in transplant toxicity-related mortality (HR = 2.5; P = 0.029). In addition, the TYMP genotype of donors was associated with the risk of chronic graft-versus-host disease (GVHD)-carriers of the minor allele being at an increased risk of developing this complication ([HR] = 1.7; P = 0.039). The impact of such polymorphism on the risk of chronic GVHD is limited to patients transplanted in early stage disease (HR = 2.2; P = 0.019). The combination of a donor harboring the minor allele with a patient homozygous for the major allele was associated with the highest risk of chronic GVHD (HR = 2.8; P = 0.008). These findings provide the first evidence of the significant impact of the TYMP genotype upon the clinical outcome of patients treated with HLA-identical sibling allo-SCT.

DCA increases the antitumor effects of capecitabine in a mouse B16 melanoma allograft and a human non-small cell lung cancer A549 xenograft

PURPOSE

Capecitabine is one of the few chemotherapy drugs with high oral availability. Recently, sodium dichloroacetate (DCA) has shown great potential as an anticancer agent. In the present study, we assessed the anticancer effect of DCA in combination with capecitabine for cancers that modestly expressed TP.

METHODS

A mouse B16 melanoma allograft and a human non-small cell lung cancer A549 xenograft were used to assess the effect of DCA and capecitabine combined treatment. Histology and immunohistochemistry were used to detect the apoptosis and proliferation of cancer cells. Real-time PCR and Western blot were carried out to detect the expression of TP and caspases, respectively.

RESULTS

For the first time, we report that DCA increased the antitumor effects of capecitabine in a mouse B16 allograft and a human A549 xenograft by promoting apoptosis of tumor cells. DCA has little effect on the expression of TP.

CONCLUSIONS

Our finding suggests that DCA in combination with capecitabine might be potential as a new therapeutic regimen against some cancers.

Trimodality therapy for stage II-III carcinoma of the esophagus: a dose-ranging study of concurrent capecitabine, docetaxel, and thoracic radiotherapy

PURPOSE

This dose-escalation study was performed to determine the recommended phase II dose of oral capecitabine to be delivered concurrently with thoracic radiation therapy and weekly docetaxel in patients with locally advanced esophageal carcinoma.

METHODS

Patients with operable stage II or III esophageal carcinoma were staged by endoscopic ultrasonography and computed tomography. Two cycles of docetaxel (80 mg/m) and carboplatin (target area under the concentration-time curve: 6 mg/ml × min) were delivered over 6 weeks. This was followed by concurrent weekly docetaxel (15 mg/m), thoracic radiotherapy (50.4 Gy in 28 fractions), and increasing doses of capecitabine (500-3500 mg) given before each fraction of radiotherapy. After restaging, responding patients continued to esophagectomy within 4 to 8 weeks of completing chemoradiotherapy.

RESULTS

Forty-four patients were enrolled, and 40 were assessable for the dose-ranging component of concurrent chemoradiotherapy. Endoscopic ultrasonography stages at enrollment were T3N1 (29 patients), T3N0 (4 patients), T2N1 (6 patients), and T4N0 (one patient). The maximum tolerated dose of capecitabine was 3500 mg. Thirty-six patients had surgery; 83% had R0 resection, and 17% had pathological complete response. Median overall survival was 23.5 months, with 34 and 27% alive at 3 and 5 years.

CONCLUSION

The recommended phase II dose of capecitabine is 3500 mg when given concurrently with 50.4 Gy of thoracic radiotherapy in 28 fractions and weekly docetaxel. This trimodality therapy for operable locally advanced esophageal carcinoma was very well tolerated and remarkably active. This regimen holds promise for the treatment of esophageal carcinoma and warrants further investigation.

A randomized phase II study comparing capecitabine alone with capecitabine and oral cyclophosphamide in patients with advanced breast cancer-cyclox II

BACKGROUND

Capecitabine and cyclophosphamide are active in patients with advanced breast cancer, have non-overlapping toxic effects and synergy pre-clinically. We explored the efficacy and toxic effect of an all-oral combination of capecitabine with cyclophosphamide versus capecitabine alone in a multicentre, randomized, phase II study.

PATIENTS AND METHODS

Patients with locally advanced or metastatic breast cancer were randomized to treatment with capecitabine given continuously (666 mg/m(2) b.i.d. days 1-28) alone (C) or with oral cyclophosphamide (100 mg/m(2) days 1-14 of a 28-day cycle) (CCy) for up to six cycles.

RESULTS

Eighty-two patients were randomized. There was no complete response. The proportions with partial response were 36% on C and 44% on CCy, a difference of 7.9% [95% confidence interval (CI) -13.4 to 29.1]. Significant toxic effect was uncommon: grade ≥3 diarrhoea in 4 (10%) versus 1 (3%) patients; grade ≥3 fatigue in 2 (5%) versus 5 patients (13%) and grade ≥2 hand-foot syndrome in 7 (17%) versus 11 (28%) patients receiving C versus CCy, respectively. Median progression-free survival was 3.1 months on C and 6.9 months on CCy, not significantly different statistically. There was no difference in overall survival.

CONCLUSION

The difference in tumour response suggests a reasonable chance that CCy is superior to C alone.

Phase I trial of capecitabine rapidly disintegrating tablets and concomitant radiation therapy in children with newly diagnosed brainstem gliomas and high-grade gliomas

BACKGROUND

We conducted a phase I study to estimate the maximum tolerated dose and describe the dose-limiting toxicities and pharmacokinetics of oral capecitabine rapidly disintegrating tablets given concurrently with radiation therapy to children with newly diagnosed brainstem or high-grade gliomas.

METHODS

Children 3-21 y with newly diagnosed intrinsic brainstem or high-grade gliomas were eligible for enrollment. The starting dose was 500 mg/m(2), given twice daily, with subsequent cohorts enrolled at 650 mg/m(2) and 850 mg/m(2) using a 3 + 3 phase I design. Children received capecitabine at the assigned dose daily for 9 wks starting from the first day of radiation therapy (RT). Following a 2-wk break, patients received 3 courses of capecitabine 1250 mg/m(2) twice daily for 14 days followed by a 7-day rest. Pharmacokinetic sampling was performed in consenting patients. Six additional patients with intrinsic brainstem gliomas were enrolled at the maximum tolerated dose to further characterize the pharmacokinetic and toxicity profiles.

RESULTS

Twenty-four patients were enrolled. Twenty were fully assessable for toxicity. Dose-limiting toxicities were palmar plantar erythroderma (grades 2 and 3) and elevation of alanine aminotransferase (grades 2 and 3). Systemic exposure to capecitabine and metabolites was similar to or slightly lower than predicted based on adult data.

CONCLUSIONS

Capecitabine with concurrent RT was generally well tolerated. The recommended phase II capecitabine dose when given with concurrent RT is 650 mg/m(2), administered twice daily. A phase II study to evaluate the efficacy of this regimen in children with intrinsic brainstem gliomas is in progress (PBTC-030).

Pharmacokinetic evaluation of capecitabine in breast cancer

INTRODUCTION

Capecitabine , an oral prodrug of 5-fluorouracil (5-FU), is adsorbed in its intact form through the intestine and metabolized to 5-FU in tumour cells. In metastatic breast cancer (MBC), capecitabine is an effective and well-tolerated therapeutic option both in monotherapy and in combination with chemotherapeutic or molecular-targeted agents.

AREAS COVERED

We summarized data on pharmacokinetics and pharmacodynamics of capecitabine. We also produced a general review of the most relevant clinical studies of capecitabine in MBC. A literature search was performed using PubMed database including selected articles published in English language up to October 2012.

EXPERT OPINION

The unique pharmacodynamic/pharmacokinetic features represent the bases of the reduced toxicity and the activity of capecitabine in several tumours. Although during the past 10 years there has been an increasing use of this drug in MBC both as single agent and in combination, encouraging results of well tolerated and active combinations with novel agents will lead to a more extensive and protracted use of capecitabine. In view of this, some aspects should be further clarified such as the optimal starting dose and the introduction of alternative schedules of treatment.

Predictive markers of capecitabine sensitivity identified from the expression profile of pyrimidine nucleoside-metabolizing enzymes

Molecular markers predicting sensitivity to anticancer drugs are important and useful not only for selecting potential responders but also for developing new combinations. In the present study, we analyzed the difference in the sensitivity of xenograft models to capecitabine (Xeloda®), 5'-deoxy-5-fluorouridine (5'-DFUR, doxifluridine, Furtulon®) and 5-FU by comparing the mRNA levels of 12 pyrimidine nucleoside-metabolizing enzymes. Amounts of mRNA in the tumor tissues of 80 xenograft models were determined by real-time RT-PCR and mutual correlations were examined. A clustering analysis revealed that the 12 enzymes were divided into two groups; one group consisted of 8 enzymes, including orotate phosphoribosyl transferase (OPRT), TMP kinase (TMPK) and UMP kinase (UMPK), and was related to the de novo synthesis pathway for nucleotides, with mRNA expression levels showing significant mutual correlation. In the other group, 4 enzymes, including thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD), were involved in the salvage/degradation pathway of the nucleotides, and the mRNA levels of this group were dispersed more widely than that of the de novo group. Antitumor activity was assessed in 24 xenograft models for each drug. The antitumor activity of capecitabine and 5'-DFUR correlated significantly with the mRNA levels of TP and with the TP/DPD ratio, whereas the activity of 5-FU correlated significantly with OPRT, TMPK, UMPK and CD. In a stepwise regression analysis, TP and DPD were found to be independent predictive factors of sensitivity to capecitabine and 5'-DFUR, and UMPK was predictive of sensitivity to 5-FU. These results indicate that the predictive factors for sensitivity to capecitabine and 5'-DFUR in xenograft models may be different from those for 5-FU, suggesting that these drugs may have different responders in clinical usage.

Antitumor effects of FP3 in combination with capecitabine on PDTT xenograft models of primary colon carcinoma and related lymphatic and hepatic metastases

FP3 is an engineered protein which contains the extracellular domain 2 of VEGF receptor 1 (Flt-1) and extracellular domain 3 and 4 of VEGF receptor 2 (Flk-1, KDR) fused to the Fc portion of human immunoglobulin G 1. Previous studies demonstrated its antiangiogenic effects in vitro and in vivo, and its antitumor activity in vivo. In this study, patient-derived tumor tissue (PDTT) xenograft models of primary colon carcinoma and lymphatic and hepatic metastases were established for assessment of the antitumor activity of FP3 in combination with capecitabine. Xenografts were treated with FP3, capecitabine, alone or in combination. After tumor growth was confirmed, volume and microvessel density in tumors were evaluated. Levels of VEGF, and PCNA in the tumor were examined by immunohistonchamical staining, level of thymidine phosphorylase (TP) was examined by ELISA, and levels of related cell signaling pathways proteins expression were examined by western blotting. FP3 in combination with capecitabine showed significant antitumor activity in three xenograft models (primary colon carcinoma, lymphatic metastasis, and hepatic metastasis). The microvessel density in tumor tissues treated with FP3 in combination with capecitabine was lower than that of the control. Antitumor activity of FP3 in combination with capecitabine was significantly higher than that of each agent alone in three xenograft models (primary colon carcinoma, lymphatic metastasis, and hepatic metastasis). This study indicated that addition of FP3 to capecitabine significantly improved tumor growth inhibition in the PDTT xenograft models of primary colon carcinoma and lymphatic and hepatic metastases.

The effect of chemotherapy or radiotherapy on thymidine phosphorylase and dihydropyrimidine dehydrogenase expression in cancer of the uterine cervix

OBJECTIVE

Levels of 5-FU metabolic or related enzymes, particularly thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD), have been investigated in various cancer types, including uterine cervical cancer. Intratumoral TP levels have been reported to increase in response to several chemotherapeutic agents or irradiation in both xenografts and clinical studies. In cervical cancer, however, only a few studies about changes in TP and DPD expression associated with cancer treatment have been published. We evaluated the effect of chemotherapy and/or irradiation on TP and DPD expression in cervical squamous cell carcinoma.

STUDY DESIGN

Of 27 patients in this study, 12 patients underwent neoadjuvant chemotherapy consisting of nedaplatin, ifosfamide, and/or peplomycin followed by radical surgery, and 15 patients underwent radiotherapy (n=8) or chemoradiotherapy with nedaplatin (n=7) as initial treatment. Tumor specimens were obtained from biopsies acquired before treatment and after administration of chemotherapy (2 weeks after the first and second cycles), and after irradiation with 10 Gy, 20 Gy, and 30 Gy. These specimens were used to measure TP and DPD levels by ELISA.

RESULTS

In the 12 patients who received neoadjuvant chemotherapy, intratumoral TP and DPD levels did not change. In contrast, in the 15 patients who underwent radiotherapy or chemoradiotherapy with nedaplatin, TP or DPD expression appeared to be slightly increased or decreased, respectively, after irradiation with 20 Gy, and consequently the TP/DPD ratio was significantly higher after irradiation with 20 Gy than before irradiation.

CONCLUSIONS

These results suggest a clinical advantage of chemoradiotherapy with capecitabine or doxyfluridine over radiotherapy alone via the elevation of the TP/DPD ratio in cervical squamous cell carcinoma. However, no advantage of combination chemotherapy with these 5-FU derivatives was demonstrated. Therefore, further evaluation with a larger number of patients or with other chemotherapeutic agents is required to confirm these observations.

Randomized phase II non-inferiority study (NO16853) of two different doses of capecitabine in combination with docetaxel for locally advanced/metastatic breast cancer

BACKGROUND

This phase II study investigated whether a lower-than-approved dose of capecitabine, plus docetaxel (XT), would improve tolerability versus standard-dose XT without compromising efficacy.

PATIENTS AND METHODS

Women aged ≥18 years with locally advanced/metastatic breast cancer resistant to anthracycline-based chemotherapy in the (neo)adjuvant, first- or second-line metastatic setting were eligible. Patients were randomly assigned to receive standard-dose XT (capecitabine 1250 mg/m(2) twice daily, days 1-14; docetaxel 75 mg/m(2), day 1 every 3 weeks) or low-dose XT (capecitabine 825 mg/m(2) twice daily, days 1-14; docetaxel as above). The primary objective was to demonstrate non-inferiority of low-dose to standard-dose XT in terms of progression-free survival (PFS).

RESULTS

470 patients were randomly allocated in a 1 : 1 ratio to standard-dose or low-dose XT. Median PFS was 7.9 versus 5.8 months [hazard ratio 1.16, 95% confidence interval (CI) 0.95-1.43] in the standard-dose and low-dose arms, respectively. The upper limit of the 95% CI was above the predefined non-inferiority margin (1.35, P = 0.078). Secondary efficacy end points were consistent with PFS. The frequency and severity of adverse events was similar in both treatment arms.

CONCLUSIONS

Non-inferiority of low-dose to standard-dose XT in terms of PFS was not demonstrated; this may be due to regional subgroup effects.

Phase II trial of simple oral therapy with capecitabine and cyclophosphamide in patients with metastatic breast cancer: SWOG S0430

BACKGROUND

Interest in oral agents for the treatment of metastatic breast cancer (MBC) has increased because many patients prefer oral to i.v. regimens. We evaluated a simple oral combination of capecitabine with cyclophosphamide (CPA) for MBC.

METHODS

The trial was designed to determine whether or not combination therapy would achieve a 42% response rate (RR) using the Response Evaluation Criteria in Solid Tumors (RECIST) in MBC. Patients with two or fewer prior chemotherapy regimens for MBC were eligible. Those with estrogen receptor-positive MBC had to have progressed on endocrine therapy. Patients had measurable disease or elevated mucin (MUC)-1 antigen and received CPA, 100 mg daily on days 1-14, and capecitabine, 1,500 mg twice daily on days 8-21, in 21-day cycles.

RESULTS

In 96 eligible patients, the median progression-free survival (PFS) interval was 5.9 months (95% confidence interval [CI], 3.7-8.0 months) and median overall survival (OS) time was 18.8 months (95% CI, 13.1-22.0 months). The RR was 36% (95% CI, 26%-48%) in 80 patients with measurable disease. The MUC-1 antigen RR was 33% (95% CI, 20%-48%), occurring in 15 of 46 patients with elevated MUC-1 antigen. Toxicity was mild, with no treatment-related deaths.

CONCLUSIONS

PFS, OS, and RR outcomes with capecitabine plus CPA compare favorably with those of capecitabine monotherapy and combination therapy with bevacizumab, sorafenib, or ixabepilone. The addition of these other agents to capecitabine does not improve OS time in MBC patients, and this single-arm study does not suggest that the addition of CPA to capecitabine has this potential in an unselected MBC population. When OS prolongation is the goal, clinicians should choose single-agent capecitabine.

Evaluation of oral chemotherapy with capecitabine and cyclophosphamide plus thalidomide and prednisone in prostate cancer patients

PURPOSE

The aim of this study was to evaluate clinical outcomes of second-line chemotherapy with capecitabine and cyclophosphamide (CTX) plus thalidomide and prednisone in refractory advanced castrate-resistant prostate cancer (CRPC) patients.

METHODS

We retrospectively reviewed patients with advanced CRPC who had previously progressed to first-line docetaxel-based chemotherapy. Patients were given second-line chemotherapy with capecitabine and CTX plus thalidomide and prednisone throughout the course. Patients were evaluated for response and toxicity, and treatment was continued until the disease progression or excessive toxicity was noted.

RESULTS

From April 2007 to February 2010, a total of 28 patients (median age, 72.8 ± 2.9 years) received second-line chemotherapy. The median cycle and duration of metronomic chemotherapy were six (range: 1-12) cycles and 6.3 (range 1.5-20.5) months, respectively. Prostatic-specific antigen was decreased by more than 50% in 10 (35.7%) of the 28 patients. All patients had bone metastases, and 8 patients (28.6%) had measurable soft tissue lesions. Among the 8 patients, 1 patient achieved partial response, and 3 patients had stabilized disease. With a median follow-up time of 29.5 (95% CI, 26.4-33.4) months, median composite progression-free survival and overall survival were 4.7 (95% CI, 3.4-5.7) months and 19.5 (95% CI, 18.9-25.5) months, respectively. No grade 3-4 toxicity was observed, and none of the patients experienced grade 3-4 hematological and nonhematological toxicities.

CONCLUSIONS

These data suggested that oral combination second-line chemotherapy with capecitabine and CTX plus thalidomide and prednisone offers promising activity with an excellent safety profile for patients with advanced CRPC.

Adjuvant capecitabine, docetaxel, cyclophosphamide, and epirubicin for early breast cancer: final analysis of the randomized FinXX trial

PURPOSE

Capecitabine is an active agent in the treatment of breast cancer. It is not known whether integration of capecitabine into an adjuvant regimen that contains a taxane, an anthracycline, and cyclophosphamide improves outcome in early breast cancer.

PATIENTS AND METHODS

Women with axillary node-positive or high-risk node-negative breast cancer were randomly assigned to receive either three cycles of docetaxel and capecitabine (TX) followed by three cycles of cyclophosphamide, epirubicin, and capecitabine (CEX; n = 753) or three cycles of docetaxel (T) followed by three cycles of cyclophosphamide, epirubicin, and fluorouracil (CEF; n = 747). The primary end point was recurrence-free survival (RFS).

RESULTS

During a median follow-up time of 59 months, 214 RFS events occurred (local or distant recurrences or deaths; TX/CEX, n = 96; T/CEF, n = 118). RFS was not significantly different between the groups (hazard ratio [HR], 0.79; 95% CI, 0.60 to 1.04; P = .087; 5-year RFS, 86.6% for TX/CEX v 84.1% for T/CEF). Fifty-six patients assigned to TX/CEX died during the follow-up compared with 75 of patients assigned to T/CEF (HR, 0.73; 95% CI, 0.52 to 1.04; P = .080). In exploratory analyses, TX/CEX improved breast cancer-specific survival (HR, 0.64; 95% CI, 0.44 to 0.95; P = .027) and RFS in women with triple-negative disease and in women who had more than three metastatic axillary lymph nodes at the time of diagnosis. We detected little severe late toxicity.

CONCLUSION

Integration of capecitabine into a regimen that contains docetaxel, epirubicin, and cyclophosphamide did not improve RFS significantly compared with a similar regimen without capecitabine.

Capecitabine in the management of colorectal cancer

5-Fluorouracil has been a mainstay in the treatment of colorectal cancer for nearly five decades; however, the use of oral formulations of the medication has been gaining increasing traction since capecitabine was approved for use in adjuvant settings by the US Food and Drug Administration in 2005. The use of capecitabine has since spread to a number of off-label indications, including the treatment of advanced or metastatic colorectal cancer and the neoadjuvant treatment of rectal cancer. In light of increasing utilization, it is critical that clinicians have a firm understanding of the literature supporting capecitabine across various settings as well as the attributes of the drug, such as its dosing recommendations, side-effect profile, and use in the elderly. The purpose of this review is to synthesize the literature in a fashion that can be used to help guide decisions. In a setting of increasing focus on cost, the pharmacoeconomic literature is also briefly reviewed.

Heterogeneous nuclear ribonucleoprotein H1/H2-dependent unsplicing of thymidine phosphorylase results in anticancer drug resistance

Thymidine phosphorylase (TP) catalyzes the conversion of thymidine to thymine and 2-deoxyribose-1-phosphate. The latter plays an important role in induction of angiogenesis. As such, many human malignancies exhibit TP overexpression that correlates with increased microvessel density, formation of aggressive tumors, and dismal prognosis. Because TP is frequently overexpressed in cancer, pro-drugs were developed that utilize TP activity for their bioactivation to cytotoxic drugs. In this respect, TP is indispensable for the pharmacologic activity of the chemotherapeutic drug capecitabine, as it converts its intermediary metabolite 5'-deoxyfluorouridine to 5-fluorouracil. Thus, loss of TP function confers resistance to the prodrug capecitabine, currently used for the treatment of metastatic colorectal cancer and breast cancer. However, drug resistance phenomena may frequently emerge that compromise the pharmacologic activity of capecitabine. Deciphering the molecular mechanisms underlying resistance to TP-activated prodrugs is an important goal toward the overcoming of such drug resistance phenomena. Here, we discovered that lack of TP protein in drug-resistant tumor cells is due to unsplicing of its pre-mRNA. Advanced bioinformatics identified the family of heterogeneous nuclear ribonucleoproteins (hnRNP) H/F as candidate splicing factors potentially responsible for impaired TP splicing. Indeed, whereas parental cells lacked nuclear localization of hnRNPs H1/H2 and F, drug-resistant cells harbored marked levels of these splicing factors. Nuclear RNA immunoprecipitation experiments established a strong binding of hnRNP H1/H2 to TP pre-mRNA, hence implicating them in TP splicing. Moreover, introduction of hnRNP H2 into drug-sensitive parental cells recapitulated aberrant TP splicing and 5'-deoxyfluorouridine resistance. Thus, this is the first study identifying altered function of hnRNP H1/H2 in tumor cells as a novel determinant of aberrant TP splicing thereby resulting in acquired chemoresistance to TP-activated fluoropyrimidine anticancer drugs.

Activation of Stat1, IRF-1, and NF-kappaB is required for the induction of uridine phosphorylase by tumor necrosis factor-alpha and interferon-gamma

Uridine phosphorylase (UPase) has been shown to be induced in various human and murine tumors and could potentially serve as a specific target for the modulation of tumor-selectivity of fluoropyrimidines. However, the signaling mechanisms underlying the regulation of UPase gene expression have not been determined. In this study, we investigated the effects of IFN-gamma on the regulation of TNF-alpha-induced UPase activity and have uncovered the molecular mechanisms of this potentiation, utilizing murine EMT6 breast cancer cells. Our data has shown that IFN-gamma can significantly increase UPase mRNA expression and the enzymatic activity induced by TNF-alpha in a dose-dependent manner, resulting in an enhanced sensitivity to 5-fluorouracil (5-FU) and 5'-Deoxy-5-fluorouridine (5'DFUR). We have previously shown that TNF-alpha activates NF-kappaB through increased translocation of NF-kappaB p65 from the cytoplasm into the nuclei. Exposure to IFN-gamma mainly affects nuclear IRF-1 and STAT1 in EMT6, but inhibits NF-kappaB p65 activity, indicating that the cooperative stimulation was the result of the independent activation of NF-kappaB, STAT1 and IRF-1 transcriptional factors through binding to their unique sites in the UPase promoter. Notably, the activation of NF-kappaB and STAT1 in human breast tissues is consistent with UPase activity; signifying their role in the up-regulation of the UPase gene expression in human tumors.

Adjuvant capecitabine in combination with docetaxel and cyclophosphamide plus epirubicin for breast cancer: an open-label, randomised controlled trial

BACKGROUND

Standard adjuvant chemotherapy regimens for patients with moderate-to-high-risk early breast cancer typically contain a taxane, an anthracycline, and cyclophosphamide. We aimed to investigate whether integration of capecitabine into such a regimen enhances outcome.

METHODS

In this open-label trial, we randomly assigned (centrally by computer; stratified by node status, HER2 status, and centre) 1500 women with axillary node-positive or high-risk node-negative breast cancer to either three cycles of capecitabine and docetaxel followed by three cycles of cyclophosphamide, epirubicin, and capecitabine (capecitabine group, n=753), or to three cycles of docetaxel followed by three cycles of cyclophosphamide, epirubicin, and fluorouracil (control group, n=747). The primary endpoint was recurrence-free survival. A planned interim analysis was done after 3 years' median follow-up. Efficacy analyses were by modified intention to treat. The study is registered with ClinicalTrials.gov, number NCT00114816.

FINDINGS

Two patients in each group were excluded from efficacy analyses because of withdrawal of consent or distant metastases. After a median follow-up of 35 months (IQR 25.5-43.6), recurrence-free survival at 3 years was better with the capecitabine regimen than with control (93%vs 89%; hazard ratio 0.66, 95% CI 0.47-0.94; p=0.020). The capecitabine regimen was associated with more cases of grade 3 or 4 diarrhoea (46/740 [6%] vs 25/741 [3%]) and hand-foot syndrome (83/741 [11%] vs 2/741 [<1%]) and the control regimen with more occurrences of grade 3 or 4 neutropenia (368/375 [98%] vs 325/378 [86%]) and febrile neutropenia (65/741 [9%] vs 33/742 [4%]). More patients discontinued planned treatment in the capecitabine group than in the control group (178/744 [24%] vs 23/741 [3%]). Four patients in the capecitabine group and two in the control group died from potentially treatment-related causes.

INTERPRETATION

The capecitabine-containing chemotherapy regimen reduced breast cancer recurrence compared with a control schedule of standard agents. Capecitabine administration was frequently discontinued because of adverse effects.

FUNDING

Roche, Sanofi-Aventis, AstraZeneca, Cancer Society of Finland.

Efficacy of doxifluridine combined with weekly paclitaxel therapy in the treatment of advanced or recurrent breast cancer: results of the JMTO BC01 phase II trial

We conducted a phase II study to determine the availability and safety of combination chemotherapy with weekly paclitaxel and doxifluridine (a capecitabine metabolite) in the treatment of advanced or recurrent breast cancer. Patients were treated with a combination chemotherapy regimen: doxifluridine was orally administered at 800 mg/day for 14 days, followed by a 7-day washout period. Paclitaxel was given intravenously on days 1 and 8 at 80 mg/m2 for 1 h, followed by a 1-week washout period. This 3-week cycle of therapy was repeated as long as possible (at least eight cycles) until the progression of the tumor and drug-related adverse effects were no longer observed. From May 2003 to December 2005, 26 patients were enrolled in the study. The overall response rate was 53.8% (95% confidence interval, 33.4-73.4%). The clinical benefit rate, including long-term no change, was 65.4% (95% confidence interval, 44.3-82.8%). Time to progression and survival time were 297 and 1182 days, respectively, for the 26 enrolled patients. No severe toxicities were observed. Grade 3/4 leucopenia in three patients, neutropenia in five patients, increased serum creatinine in three patients, hypercalemia in one patient, hypocalcemia in one patient, nausea/vomiting in two patients, and diarrhea in one patient. The good response rate and long time to progression and overall survival time of this doxifluridine combined with weekly paclitaxel therapy indicate its potential as a first-line or second-line treatment for advanced or recurrent breast cancer patients.

Metronomic cyclophosphamide and capecitabine combined with bevacizumab in advanced breast cancer

PURPOSE

Metronomic chemotherapy has shown efficacy in patients with metastatic breast cancer. When used in association with targeted antiangiogenic drugs, it was more active than metronomic therapy alone in preclinical and clinical studies.

PATIENTS AND METHODS

Patients with advanced breast cancer were candidates to receive metronomic oral capecitabine (500 mg thrice daily) and cyclophosphamide (50 mg daily) plus bevacizumab (10 mg/kg every 2 weeks).

RESULTS

In 46 assessable patients, we observed one complete response (CR; 2%), 21 partial responses (PR; 46%), 19 patients (41%) with stable disease (SD), and five patients (11%) with progressive disease, for an overall response rate of 48% (95% CI, 33% to 63%). Additional long-term disease stabilization (SD > or = 24 weeks) occurred in eight patients, for an overall clinical benefit (CR + PR + SD > or = 24 weeks) of 68% (95% CI, 51% to 81%). Median time to progression was 42 weeks (95% CI, 26 to 72 weeks). Toxicity was generally mild. Grade 3 or 4 nonhematologic adverse effects included hypertension (n = 8), transaminitis (n = 2), and nausea/vomiting (n = 2). Higher baseline circulating endothelial cells (CECs) were correlated with overall response (P = .02), clinical benefit (P = .01), and improved progression-free survival (P = .04).

CONCLUSION

Treatment with metronomic capecitabine and cyclophosphamide in combination with bevacizumab was effective in advanced breast cancer and was minimally toxic. The number of baseline CECs significantly correlated with response and outcome, therefore supporting further studies on this surrogate marker for the selection of patients to be candidates for antiangiogenic treatments.

Dose-finding phase I and pharmacokinetic study of capecitabine (Xeloda) in combination with epirubicin and cyclophosphamide (CEX) in patients with inoperable or metastatic breast cancer

OBJECTIVE

The present study aimed to identify the recommended dose (RD) of capecitabine, epirubicin and cyclophosphamide (CEX) combination treatment for inoperable or metastatic breast cancer and to assess response rate, tolerability and pharmacokinetics in Japanese patients.

METHODS

Patients received 3-week cycles of fixed-dose intravenous cyclophosphamide (600 mg/m(2), day 1), intravenous epirubicin (75-100 mg/m(2), day 1) and oral capecitabine (628-900 mg/m(2) twice daily, days 1-14). Dose escalation/deescalation decisions for consecutive cohorts were made using the continual reassessment method (CRM). RD was defined as dose level closest to that causing dose-limiting toxicity (DLT) in 33% of patients.

RESULTS

Among the 17 patients enrolled, 3 experienced DLT (hand-foot syndrome, anorexia, mucositis; all grade 3) and 3 (18%) febrile neutropenia. Based on CRM calculation, mean DLT occurrence probabilities (90% confidence intervals in parentheses) for levels 2, 3 and 4 were 21% (8-42%), 35% (17-56%) and 56% (38-71%), respectively. Level 3 was thus chosen as the RD. Combination treatment did not affect pharmacokinetic parameters of capecitabine, epirubicin or their metabolites. Objective responses were achieved by 7 patients (41%), including partial responses in 4 of 6 patients (67%) receiving the RD.

CONCLUSION

CEX represents a well-tolerated regimen, and RD for Japanese patients was determined to be capecitabine 900 mg/m(2) twice daily in combination with epirubicin 90 mg/m(2) and cyclophosphamide 600 mg/m(2) using the CRM.

Anthracyclines and taxanes induce the upregulation of thymidine phosphorylase in breast cancer cells

We have investigated the immunohistochemical expression of thymidine phosphorylase before and after the administration of anthracycline, and/or anthracycline/taxane-based preoperative chemotherapy in a consecutive series of 55 patients with primary operable breast cancer. Pretreatment, large core breast biopsies and the corresponding surgical samples were retrospectively evaluated for thymidine phosphorylase immunoreactivity. Immunohistochemical expression was evaluated on tumor cells (nuclear and cytoplasmic staining) and on stromal cells (cytoplasmic staining). The cytoplasmic expression of thymidine phosphorylase was enhanced in the tumor cells after treatment (P=0.04). An increase in thymidine phosphorylase cytoplasmic tumor expression was observed in 33% (95% confidence interval: 19-50%) of patients after preoperative chemotherapy (P=0.01). No statistically significant nuclear staining changes were observed in response to treatment. Similarly, no significant changes of the enzyme expression were seen in stromal cells. This study provides further evidence that, at least in breast cancer, thymidine phosphorylase is upregulated after anthracycline and/or taxane-containing chemotherapy. Accordingly, it supports the hypothesis of a synergistic effect between thymidine phosphorylase-modulating and thymidine phosphorylase-targeting anticancer agents. Translational studies, specifically designed on the basis of this rationale, are eagerly waited.

Capecitabine and paclitaxel combination chemotherapy for inoperable or recurrent breast cancer: a phase I dose-finding study by the Kinki Breast Cancer Study Group

BACKGROUND

The combination of capecitabine and paclitaxel (XP) has demonstrated synergistic antitumor activity in preclinical models. Three-weekly XP regimens have demonstrated excellent efficacy in phase II and III trials in metastatic breast cancer. We conducted a dose-finding study to identify the recommended 4-weekly XP regimen in patients with inoperable or recurrent breast cancer for phase II evaluation.

METHODS

Eligible patients had inoperable or recurrent breast cancer previously treated with chemotherapy (but not capecitabine or paclitaxel) in the (neo)adjuvant or metastatic setting. Each 4-week treatment cycle consisted of escalating doses of capecitabine (628 or 829 mg/m(2) twice daily [b.i.d.] on days 1-21) and paclitaxel (80 or 90 mg/m(2) on days 1, 8, and 15). Dose-limiting toxicities (DLT) were evaluated during the first two cycles.

RESULTS

Nine patients were treated. At dose level 1 (capecitabine 628 mg/m(2) b.i.d. plus paclitaxel 80 mg/m(2)), one patient experienced a DLT (grade 3 non-hematologic toxicity). There were no further DLTs at dose level 1 or 2. Although the MTD was not reached, dose level 2 (capecitabine 829 mg/m(2) b.i.d., days 1-21, plus paclitaxel 80 mg/m(2), days 1, 8, and 15, every 28 days) is recommended for phase II evaluation, taking into consideration the single-agent doses used in Japan and the doses identified in Western studies of 3-weekly XP. The overall response rate was 44%; all patients treated at dose level 2 achieved a partial response.

CONCLUSIONS

This 4-weekly XP regimen was well tolerated, active in patients with pretreated advanced breast cancer, and could be given as outpatient treatment. These results are consistent with findings of phase II and III trials evaluating 3-weekly regimens, and indicate that further investigation of a 4-weekly XP regimen is warranted.

Therapeutic potential of the dual-targeted TAS-102 formulation in the treatment of gastrointestinal malignancies

Current treatment modalities for cancer combine cytotoxic drugs against DNA and novel targeted drugs affecting signal transduction pathways, which are required for growth progression and metastasizing tumors. Classical chemotherapeutic regimens for gastro-intestinal tumors include antimetabolites based on 5-fluorouracil (5FU), the platinum analog oxaliplatin and the topoisomerase inhibitor irinotecan. The thymidine analog trifluorothymidine (TFT) has been shown to bypass resistance pathways for 5FU derivatives (S-1, UFT, Xeloda) in model systems, while concurrent application with a thymidine phosphorylase inhibitor (TPI) increases the bioavailability of TFT, thereby potentiating the in vivo efficacy of TFT. The formulation TAS-102 is given orally in a 1.0:0.5 molar ratio (TFT:TPI). The formulation is dual-targeted due to the cytotoxic effect of TFT, which is enhanced by TPI, while TPI also exerts antiangiogenic effects by inhibiting thymidine phosphorylase (TP), also known as platelet-derived endothelial cell growth factor. Evidence is accumulating from in vitro and in vivo preclinical studies that these properties favor further combinations with other cytotoxic agents currently being used in the treatment of gastro-intestinal tumors. Also treatment with targeted agents will synergistically down-regulate signal transduction pathways responsible for growth and progression of tumors. In this review, we summarize the available information on (clinical) pharmacology, mechanisms of action, pharmacodynamic and pharmacokinetic properties, early clinical trials and future directions of the new potent combination drug TAS-102.

Capecitabine in Combination with Novel Targeted Agents in the Management of Metastatic Breast Cancer: Underlying Rationale and Results of Clinical Trials

At present there is no established standard of care for metastatic breast cancer and prognosis remains poor, although the use of newer chemotherapeutic regimens has led to modest improvements in survival. Capecitabine, an oral prodrug of 5-fluorouracil, is a promising addition to these approaches, having already shown single-agent activity against metastatic breast cancer. Following a pivotal trial demonstrating that capecitabine confers increased survival when used in combination with docetaxel, it is being investigated intensively in combined regimens using other standard chemotherapeutic agents, as well as with novel molecularly targeted therapies. Among the novel agents, the most intensively studied in combination with capecitabine is trastuzumab. Despite preclinical data suggesting that these two agents might not show additive effects, clinical trials have been very encouraging for both heavily pretreated patients and for patients receiving first-line therapy in the metastatic setting. This work is being further extended in an ongoing trial in the neoadjuvant setting. An initial trial in combination with bevacizumab, enrolling heavily pretreated patients, was less successful, but following the example of the E2100 trial, this combination is being re-examined in less heavily treated patients. In addition, this review discusses ongoing trials with an array of newer molecularly targeted agents. Significant improvement in time to progression has already been demonstrated in the combination of lapatinib and capecitabine compared with capecitabine monotherapy; for the most part, however, these trials are still in early stages.

Capecitabine for the oral treatment of metastatic breast cancer

Women with metastatic breast cancer require tailored chemotherapy that improves outcomes without compromising quality of life. Capecitabine, a pro-drug of 5-fluorouracil, is an oral fluoropyrimidine carbamate that is sequentially activated in a three-step process. This results in the preferential production of 5-fluorouracil in tumors rather than in normal surrounding tissue, improving the tolerability and efficacy of 5-fluorouracil. In combination with docetaxel, capecitabine is the first agent that has shown superior activity to single-agent docetaxel, and it is a particularly appropriate option for younger, fitter patients with rapidly progressing disease and/or visceral metastases. However, for older patients and those with comorbidities and/or after progression to taxanes, single-agent capecitabine may be the best option. Its role in earlier disease stages (adjuvant therapy) is being investigated.