Comparative effectiveness of cisplatin-based and carboplatin-based chemotherapy for treatment of advanced urothelial carcinoma.

BACKGROUND: Cisplatin-based chemotherapy is a standard treatment of metastatic urothelial carcinoma (UC), though carboplatin-based chemotherapy is frequently substituted due to improved tolerability. Because comparative effectiveness in clinical outcomes of cisplatin- versus carboplatin-based chemotherapy is lacking, a meta-analysis was carried out. METHODS: PubMed was searched for articles published from 1966 to 2010. Eligible studies included prospective randomized trials evaluating cisplatin- versus carboplatin-based regimens in patients with metastatic UC. Individual patient data were not available and survival data were inconsistently reported. Therefore, the analysis focused on overall response (OR) and complete response (CR) rates. The Mantel-Haenszel method was used for combining trials and calculating pooled risk ratios (RRs). RESULTS: A total of 286 patients with metastatic UC from four randomized trials were included. Cisplatin-based chemotherapy was associated with a significantly higher likelihood of achieving a CR [RR = 3.54; 95% confidence interval (CI) 1.48-8.49; P = 0.005] and OR (RR = 1.34; 95% CI 1.04-1.71; P = 0.02). Survival end points could not be adequately assessed due to inconsistent reporting among trials. CONCLUSIONS: Cisplatin-based, as compared with carboplatin-based, chemotherapy significantly increases the likelihood of both OR and CR in patients with metastatic UC. The impact of improved response proportions on survival end points could not be assessed.

Docetaxel and epirubicin compared with docetaxel and prednisone in advanced castrate-resistant prostate cancer: a randomised phase II study.

BACKGROUND: This randomised phase II study compared the activity and safety of the combination docetaxel (D)/epirubicin (EPI) with the conventional treatment D/prednisone (P) in advanced castrate-resistant prostate cancer (CRPC) patients. MATERIALS AND METHODS: Patients were randomly assigned to D 30 mg m(-2) as intravenous infusion (i.v.) and EPI 30 mg m(-2) i.v. every week (D/EPI arm), or D 70 mg m(-2) i.v. every 3 weeks and oral P 5 mg twice daily (D/P arm). Chemotherapy was administered until disease progression or unacceptable toxicity. RESULTS: A total of 72 patients were enrolled in the study and randomly assigned to treatment: 37 to D/EPI and 35 to D/P. The median progression-free survival (PFS) was 11.1 months (95% CI 9.2-12.6 months) in the D/EPI arm and 7.7 months (95% CI 5.7-9.4 months) in the D/P arm (P=0.0002). The median survival was 27.3 months (95% CI 22.1-30.8 months) in the D/EPI arm and 19.8 months (95% CI 14.4-24.8 months) in the D/P arm (P=0.003). Both regimens were generally well tolerated. CONCLUSION: The treatment of advanced CRPC with weekly D combined with weekly EPI was feasible and tolerable, and led to superior PFS than the treatment with 3-weekly D and oral P.

Antiphospholipid antibodies and acute-phase response in non-metastatic colorectal cancer patients.

AIM: To investigate the plasma levels and prevalence of the most common antiphospholipid antibodies, as well as their relationships with several plasma markers of inflammation, in order to characterize some aspects of cancer thrombophilia. MATERIALS AND METHODS: Eighty-three cancer patients with non-metastatic colorectal solid tumors and 94 control subjects were tested for the presence of IgG/IgM/IgA anti-cardiolipin and anti-Beta2-glycoprotein I antibodies and of several acute-phase reactants, i.e., fibrinogen, factor VIII:C and C4b-binding protein. RESULTS: In cancer patients the plasma levels of the acute-phase reactants and the IgA/IgG anti-cardiolipin and IgA anti-Beta2- glycoprotein I antibodies were significantly higher; the acute-phase reactants were significantly correlated with anti-cardiolipin antibodies; the prevalence of antiphospholipid antibodies was not significantly higher. CONCLUSIONS: In patients with non-metastatic colorectal cancer the acute-phase response is associated with antiphospholipid generation. This could represent a further pathogenetic mechanism for the short-term post-surgery thrombotic complications of patients with colorectal cancer.

Coagulation factor levels in non-metastatic colorectal cancer patients.

UNLABELLED: There is evidence that high plasma levels of factor (F) VIII, FIX, FXI and fibrinogen are independent risk factors for venous thromboembolism. AIM: To determine the plasma concentrations of several coagulation factors and C4b-binding protein (C4BP) in a group of patients with non-metastatic colorectal cancer in order to investigate some aspects of cancer-acquired thrombophilia. METHODS: Plasma fibrinogen, FII, FV, FVII, FVIII, FIX, FX, FXI and FXII activity levels and C4BP concentrations were determined in 73 patients with non-metastatic colorectal cancer (48 colon and 25 rectum) and in 67 matched control subjects. No one in either group had had previous thrombotic events. RESULTS: Mean plasma concentrations of fibrinogen (functional and antigen), FVIII, FIX, FV and C4BP were significantly higher in colorectal cancer patients than in control subjects, while FVII and FXII levels were significantly decreased. Several correlations were found between the increased coagulation factors and C4BP concentrations, while FVII was highly correlated with FXII. CONCLUSIONS: In colorectal cancer patients high plasma fibrinogen, FVIII and FIX levels might represent further risk factors for venous thrombotic complications in the immediate post-surgery period, while decreased FVII and FXII concentrations may be an index of intravascular coagulation activation, still in a subclinical phase.

Changes in bone turnover and in bone mass in women with breast cancer switched from tamoxifen to exemestane.

Recently the third generation aromatase inhibitors have proved their efficacy and tolerability compared with tamoxifen in the adjuvant treatment of women with hormone responsive early breast cancer. However, there is some concern about the possible negative impact of these drugs on bone. The aim of the study was to evaluate the effects of the steroidal aromatase inactivator exemestane on bone turnover markers and on bone mineral density (BMD). Seventy postmenopausal women (62.0+/-8.9 years) with completely resected breast cancer and who were disease-free following 2-3 years on tamoxifen were randomly assigned to continue tamoxifen (n=36) or switch to exemestane (n=34). Sixty-one patients completed the 2-year study period. Bone alkaline phosphatase (B-ALP) and the carboxy-terminal telopeptide of type I collagen (CTX) were measured at baseline and after 3, 6, 9, 12, 18 and 24 months. BMD at lumbar spine (BMD-LS), at femoral neck (BMD-FN), at total hip (BMD-T) and at whole body (BMD-WB) were measured at 6-monthly intervals. Exemestane-treated women showed significant (p<0.01) increases with respect to baseline in both B-ALP and CTX. The difference between the 2 groups reached the statistical significance at month 6 for CTX (p<0.05) and at month 9 for B-ALP (p<0.01). Moreover, the exemestane-treated women showed an early decrease in PTH serum levels (-20.4%, p<0.01 at month 6). In the E group, the percentage changes were -2.37 (p<0.05) BMD-LS, -1.24 (p<0.05) BMD-FN, -1.1 (n.s.) BMD-T, -1.03 (n.s.) BMD-WB at month 12 and -2.99 (p<0.01) BMD-LS, -1.92 (p<0.01) BMD-FN, -2.01 (p<0.05) BMD-T, -1.3 (n.s.) BMD-WB at month 24. The tamoxifen group did not show significant changes in BMD. The differences between the two groups were significant at all skeletal sites except BMD-WB. Our data suggest that switching postmenopausal women from tamoxifen to exemestane causes a marked increase in bone turnover markers with a consequent reduction in BMD. These findings could be due to both the direct effect of exemestane and to the loss of the protective effect of tamoxifen. Therefore, the postmenopausal women switched from tamoxifen to exemestane should be monitored for bone loss especially if other risk factors for osteoporosis are present.

Surgical management of advanced gastric cancer: An evolving issue.

Worldwide, gastric cancer represents the fifth most common cancer and the third leading cause of cancer deaths. Although the overall 5-year survival for resectable disease was more than 70% in Japan due to the implementation of screening programs resulting in detection of disease at earlier stages, in Western countries more than two thirds of gastric cancers are usually diagnosed in advanced stages reporting a 5-year survival rate of only 25.7%. Anyway surgical resection with extended lymph node dissection remains the only curative therapy for non-metastatic advanced gastric cancer, while neoadjuvant and adjuvant chemotherapies can improve the outcomes aimed at the reduction of recurrence and extension of survival. High-quality research and advances in technologies have contributed to well define the oncological outcomes and have stimulated many clinical studies testing multimodality managements in the advanced disease setting. This review article aims to outline and discuss open issues in current surgical management of advanced gastric cancer.

Treatment of bone metastases with dichloromethylene bisphosphonate.

PURPOSE: The study was undertaken to evaluate the effects of dichloromethylene bisphosphonate (Cl2MDP) on osteolytic and osteoblastic bone lesions from a variety of tumoral primary sites and to investigate the in vivo mechanism underlying the action of this drug. PATIENTS AND METHODS: Seventy-six patients participated in the current study: 59 had predominantly osteolytic lesions and 17 osteoblastic metastases. Sixteen patients had hypercalcemia. All of the patients received 300 mg of Cl2MDP intravenously (IV) for 7 days and then 200 mg of Cl2MDP intramuscularly (IM) for 14 days. Biochemical parameters were measured in the patients before the start of treatment and 3, 7, 14, and 21 days after beginning treatment. After the withdrawal of parenteral Cl2MDP, 59 patients with predominantly osteolytic lesions were then randomized to receive chemotherapy alone (group A, 29 cases) or chemotherapy plus Cl2MDP given at an oral dose of 1,200 mg/d (group B, 30 cases). RESULTS: Serum calcium (Ca), urinary calcium (UCa) phosphate (UPO4), and hydroxyproline (HOP) excretion levels significantly decreased in all patients, whereas no significant changes occurred in serum alkaline phosphatase (AlkPh) and bone Gla-protein (BGP) levels. In 56 patients with painful bone lesions, a progressive analgesic effect was observed mainly between day 7 and day 14. In patients with predominantly osteoblastic metastases, the Cl2MDP treatment led to a more evident hypocalcemia and an increase in both AlkPh and BGP. However, in the majority of these patients the hypocalcemia was corrected by the concurrent use of effective cytotoxic treatments capable of reducing osteoblast stimulation. During 6 months of follow-up, two pathologic fractures occurred in patients of group A, and none occurred in patients of group B. CONCLUSIONS: We conclude that Cl2MDP was effective in patients presenting bone metastases with and without hypercalcemia. Care should be taken particularly in those patients with mixed metastases when the sclerotic component is predominant, as the drug may enhance the possibility of hypocalcemia, which is generally corrected by effective cytotoxic drugs. Therefore, Cl2MDP can be considered a valuable support in the treatment of bone metastases.

Rechallenge of docetaxel combined with epirubicin given on a weekly schedule in advanced castration-resistant prostate cancer patients previously exposed to docetaxel and abiraterone acetate: a single-institution experience.

The aim of this paper was to evaluate the activity and tolerability of weekly docetaxel (D) combined with weekly epirubicin (EPI) in patients with advanced castrate-resistant prostate cancer (CRPC) previously exposed to D and abiraterone acetate (AA). Locally advanced or metastatic CRPC patients with 0-2 performance status, who had progressed after D and AA therapy, were included in the study. Previous treatment with chemotherapy agent cabazitaxel was also admitted. Treatment consisted of D 30 mg/m(2) intravenously (i.v.) and EPI 30 mg/m(2) i.v., every week (D/EPI). Chemotherapy was administered until disease progression or unacceptable toxicity. In our institution, twenty-six patients received D/EPI: their median age was 72 years (range 59-83 years). Twenty-three (88.5%) patients had bone metastases. A decrease in PSA levels ≥50% was observed in seven patients (26.9%, 95% CI: 0.11-0.47); of these, five had achieved a ≥50% PSA response during prior first-line D and six had achieved a PSA response during prior AA Among the subjects who were symptomatic at baseline, pain was reduced in nine patients (38.1%) with a significant decrease in analgesic use. Median progression-free survival was 4.4 months (95% CI, 3-5.2), and median overall survival was 10.7 months (95% CI, 8.9-18.4). Treatment was well tolerated and no grade 4 toxicities were observed. Our findings suggest that weekly D/EPI is feasible and active in heavily pretreated advanced CRPC patients and seem to support the hypothesis that the addition of EPI to D may lead to overcome the resistance to D in a subgroup of patients.

Procollagen type I carboxy-terminal propeptide as a marker of osteoblastic bone metastases.

Collagen type I is the sole collagen type found in bones and tendons. Carboxyterminal propeptide, deriving and cleaved from procollagen type I (PICP) during collagen synthesis, is delivered into the blood, where it can be measured. According to current knowledge, PICP correlates with bone collagen synthesis and bone formation rate. Elevated serum levels of PICP in patients with Paget's disease, compared with normal subjects and correlated with serum alkaline phosphatase (Alk.Ph.), have been previously described. Thus, PICP may be a valuable marker of bone formation. PICP, serum Alk.Ph., serum bone Gla protein and 24-h urinary hydroxyproline:creatinine ratio have been measured in 47 cancer patients: 27 with predominantly osteolytic lesions (5 myeloma, 15 breast, 3 lung, 2 kidney, 1 bladder, 1 thyroid) and 20 with predominantly osteoblastic lesions (18 prostate and 2 breast). The higher levels of PICP were noted in patients with osteoblastic or mixed metastases. In the entire group of patients, a statistically significant correlation between PICP and bone Gla protein (r = 0.57; P < 0.001), PICP and Alk.Ph. (r = 0.80; P < 0.001), and bone Gla protein and Alk.Ph. (r = 0.44; P < 0.01) was noted. In those patients with osteoblastic metastases we observed a significant correlation only between PICP and Alk.Ph. (r = 0.62; P < 0.003). During chemotherapy, 13 of 20 patients with osteoblastic metastases who achieved objective response or stable disease showed a more rapid and significant decrease in PICP with respect to the other bone markers. Serum PICP level could be considered a good marker of osteoblastic activity.

Hypercalcemia in breast cancer.

Hypercalcemia is relatively frequent in malignancy with or without osteolytic bone metastases. It is thought that neoplastic cells may secrete substances which not only stimulate osteoclastic activity but are also capable of modifying the absorption, excretion, and resorption of calcium and phosphate ions. Since 1987, we have studied 24 breast cancer patients with hypercalcemia (22 with bone metastases and two without). The group of 22 patients with bone metastases were divided into two subgroups. The first consisted of 10 patients with high serum levels of humoral factors, such as parathyroid hormone-related protein (PTHrP), and/or prostaglandin E2 (PGE2) and/or interleukin 1 (IL-1), and high levels of bone markers, such as alkaline phosphatase, bone Gla protein and urinary hydroxyproline. The second subgroup consisted of 12 patients with high levels of bone markers alone. Bone histologic analysis showed an osteoclastic activation surrounding metastatic tumor tissue in six out of 10 patients of the first subgroup, while an evident osteolysis caused by the tumor cells was noted in seven out of 12 patients of the second subgroup. The two patients without bone metastases showed normal biochemistry and bone histologic examination. The authors, having tried to explain the pathogenesis of hypercalcemia, emphasize the importance of humoral factors secreted by tumor cells as a direct or indirect cause of hypercalcemia. The origin of hypercalcemia remains unclear in two patients without bone metastases.

Gemcitabine increases systemic 5-fluorouracil exposure in advanced cancer patients.

A number of recent clinical trials testing the combination of 5-fluorouracil (5-FU) and gemcitabine in patients with advanced pancreatic adenocarcinoma have shown a significant clinical response rate, but also significant toxicity. As the two antimetabolites may interact at several biochemical levels along their pathways of activation, we investigated whether gemcitabine (GEM) affects 5-FU pharmacokinetics in cancer patients. Thus, we compared 5-FU pharmacokinetics in two groups of patients with various cancers who received the same schedule of 5-FU and folinic acid (FUFA), with or without GEM. There was a significant increase in systemic (5-FU) exposure and toxicity in the FUFA plus GEM group. Our finding may be useful in designing future studies of the combination in order to reduce the occurrence of side-effects and to maximise the antitumour activity.

Treatment of advanced colorectal cancer with high-dose intensity folinic acid and 5-fluorouracil plus supportive care.

This randomised clinical trial, involving patients with advanced colorectal cancer, was carried out to compare the effectiveness of accelerated folinic acid (FA) plus 5-fluorouracil (5-FU) with that of the conventional regimen of 5-FU alone. Both regimens were administered with simulataneous supportive care. 185 patients were eligible: 94 were randomly allocated to receive FA 200 mg/m2 i.v. plus 5-FU 400 mg/m2 i.v. on days 1-5 every 3 weeks; and 91 to receive 5-FU 400 mg/m2 i.v. on days 1-5 every 4 weeks. The response rate was 33.3% in the accelerated FA/5-FU and 18.6% in the 5-FU arm (P = 0.045). Median survival was 13.5 months in the FA/5-FU arm and 7.5 months in the 5-FU arm (P = 0.039). Toxicity was mild and slightly more pronounced in the FA/5-FU arm (P = 0.078). This study indicates that, in patients with advanced colorectal cancer, accelerated chemotherapy with FA and 5-FU and simultaneous supportive care is capable of achieving a higher response rate and longer survival than conventional 5-FU alone, without severe toxicity.

Tumour-associated antigen (TAA)-specific cytotoxic T cell (CTL) response in vitro and in a mouse model, induced by TAA-plasmids delivered by influenza virosomes.

We investigated influenza virosomes as a TAA-gene delivery system for use in TAA-directed anti-cancer vaccine therapy. An engineered plasmid (GC90) expressing the parathyroid hormone-related peptide (PTH-rP), a protein secreted by prostate and lung carcinoma cells, was included in influenza virosomes (GC90V). The ability of GC90V to elicit a PTH-rP-specific cytotoxic T cell (CTL) response was demonstrated in BALB/c mice immunised with intranasal (i.n.) GC90V+/-adjuvant subcutaneous (s.c.) interleukin-2 (IL-2). A PTH-rP-specific CTL response with antitumour activity was also demonstrated in human peripheral blood mononuclear cells (PBMC) stimulated in vitro with GC90V infected autologous dendritic cells (DC). These results provide a rationale for investigating GC90V in clinical trials of anticancer vaccine therapy.

Recruitment of dendritic cells and enhanced antigen-specific immune reactivity in cancer patients treated with hr-GM-CSF (Molgramostim) and hr-IL-2. results from a phase Ib clinical trial.

Experimental findings suggest that granulocyte-monocyte-colony stimulating factor (GM-CSF) synergistically interacts with interleukin-2 (IL-2) in generating an efficient antigen-specific immune response. We evaluated the toxicity, antitumour activity and immunobiological effects of human recombinant (hr)-GM-CSF and hr-IL-2 in 25 cancer patients who subcutaneously (s.c.) received hr-GM-CSF 150 microg/day for 5 days, followed by hrIL-2 s.c. for 10 days and 15 days rest. Two of the most common side-effects were bone pain and fever. Of the 24 patients evaluable for response, 3 achieved partial remission, 13 experienced stable disease, and 8 progressed. Cytokine treatment increased the number of monocytes, dendritic cells (DC), and lymphocytes (memory T cells) in the peripheral blood and enhanced the antigen-specific immunoreactivity of these patients. Our results show that the hr-GM-CSF and hr-IL-2 combination is active and well tolerated. Its biological activity may support tumour associated antigen (TAA)-specific anticancer immunotherapy by increasing antigen presenting cell (APC) activity and T cell immune competence in vivo.

Production of parathyroid hormone and parathyroid-hormone-related protein by breast cancer cells in culture.

Parathyroid-hormone-related protein (PTHrP) has been implicated in the origin of malignant hypercalcaemia. However, PTHrP production is not restricted to neoplastic cells, it is widespread among a variety of normal cell types and tissues. A physiological role for PTHrP has not been well defined. We describe a case of breast cancer with bone metastases and humoral hypercalcaemia of malignancy, with high levels of plasma C-terminal parathyroid hormone (PTH), mid-molecule PTH and PTHrP. Cells from breast cancer biopsies were cultured and medium samples assayed for the C-terminal and mid-molecule fragments, intact PTH and PTHrP. The data indicate a progressive increase in both PTH fragments and PTHrP levels, over a period of 30 days. No temporal parallelism exists between PTH fragments and PTHrP concentrations, the former being maximum at the 14th day, and the latter at the 30th day from the beginning of the culture. Our results indicate a coproduction of PTH and PTHrP by the breast cancer cells both in vivo and in vitro.

Advanced breast cancer treatment with folinic acid, 5-fluorouracil, and mitomycin C.

A total of 44 women with advanced breast cancer who had failed first- and second-line chemotherapy were given combination chemotherapy consisting of folinic acid (FA), 5-fluorouracil (5-FU) and mitomycin C (MMC). The treatment schedule was: 200 mg/m2 FA and 400 mg/m2 5-FU given i.v. over 2 h for 5 days plus 5 mg/m2 MMC given i.v. on days 3-5; in 19 patients with an Eastern Cooperative Oncology Group (ECOG) performance status of 3-4 and bone marrow depression, the MMC dose was 3 mg/m2 given i.v. on days 3-5. In all, 41 patients were evaluable for response; 15 had a partial remission (PR), 18 had stable disease (SD), and 8 showed progressive disease (PD). The median response duration was 6 months and the median survival was 10 months. Toxicity was mild and consisted mainly of stomatitis, diarrhea, and leukopenia. A rapid improvement in performance status was noted in responding patients. A striking result was the reduction of analgesics in most cases and their complete withdrawal in responding patients. This combination chemotherapy achieved satisfactory effectiveness and improved the quality of life of patients.

Comparison between CEA, TPA, CA 15/3 and hydroxyproline, alkaline phosphatase, whole body retention of 99mTc MDP in the follow-up of bone metastases in breast cancer.

The development of bone metastases in cancer can be monitored easily using three markers: 24 h urinary hydroxyproline excretion (HOP) (an index of osteoclastic activity), serum alkaline phosphatase (Alk.Ph.) (an index of osteoblastic activity) and 24 h whole body retention of 99mTc-methylene diphosphonate (WBR%) (an index of bone turnover). To evaluate the effectiveness of this group of bone tumor markers in breast cancer we compared it with the following group of three markers which are commonly used in the monitoring of breast cancer and in the follow-up of advanced disease with or without bone metastases: carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA) and breast carcinoma antigen (CA 15/3). In 48 patients with bone metastases CEA, TPA and CA 15/3 were shown to be sensitive (79%, 85%, 90% respectively), while HOP, Alk.Ph. and WBR%, which are commonly accepted as reliable markers of bone activity, showed a lower sensitivity (67%, 46%, 75% respectively). These results may be explained by the lack of osteoclastic or osteoblastic (or both) activity at the time of diagnosis. This explanation is supported by the fact that the bone markers HOP, Alk.Ph. and WBR% were found to be more sensitive than the others in the subsequent follow-up study. We conclude that in our study, CEA, TPA and CA 15/3 are at first more sensitive than Alk.Ph., HOP and WBR% but during the follow-up Alk.Ph., HOP and WBR% are possibly both more specific and more sensitive.

Histopathological and prognostic evaluation of immunohistochemical findings in colorectal cancer.

Many immunohistochemical studies have investigated the relationship between immunohistochemical characteristics and histopathological findings in colorectal tumors. One of the most extensively studied markers has been tissue CEA, although the prognostic significance of this and other antigens is still uncertain. The authors report results relative to three tumoral antigens (carcinoembryonic antigen, CEA; tissue polypeptide antigen. TPA, and carbohydrate antigen 19-9, CA 19-9) determined by immunohistochemical methods in tissue samples of 52 colorectal carcinomas. The relationship between the immunohistochemical characteristics of the neoplasms and the clinicopathologic parameters, as well as their influence on the prognosis of the patients, were examined. Positive CEA reaction has a significant relationship with grade of differentiation of the tumor while diffuse cellular expression of this antigen often indicates neoplasms extending beyond the intestinal wall and invading the lymph vessels. The number of tissue antigens expressed is significantly related to the extent of tumor spread through the intestinal wall. A greater incidence of recurrence and shorter disease-free interval and survival were observed in neoplasms that expressed tissue TPA antigen or more than one tissue antigens. In the present study the latter parameter has demonstrated to have independent prognostic significance for the disease-free interval. Immunohistochemical evaluation of antigens in colorectal carcinoma tissue shows a possible independent prognostic value of the antigenic heterogeneity of tumors, which could be related to their different biological behavior.

Gemcitabine (GEM), 5-fluorouracil (5-FU) and folinic acid (FA) in patients with different gastroenteric malignancies.

This phase II clinical trial was performed in order to evaluate the pharmacokinetics, toxicity and anti-tumor activity of a novel combination of gemcitabine (GEM), 5-fluorouracil (5-FU) and folinic acid (FA) designed on a specific translational basis. Every 4 weeks, 44 patients with various gastroenteric malignancies, 29 of whom had pancreas carcinoma, received a short intravenous (i.v.) infusion of FA (100 mg/m2) and 5-FU (400 mg/m2) on days 1-5, and GEM 1000 mg/m2 on days 1, 8 and 16. Our results suggest that, although this treatment leads to hematological and gastroenteric toxicity, it is very active in patients with pancreatic carcinoma. We therefore believe that an improved version would merit further investigation in larger scale trials.

In vitro generation of cytotoxic T lymphocytes against HLA-A2.1-restricted peptides derived from human thymidylate synthase.

5-Fluorouracil (5-FU) is a pyrimidine antimetabolite active against colorectal carcinoma and other malignancies of the digestive tract. Over-expression or mutation of thymidylate synthase (TS), the target enzyme of the 5-FU metabolite, 5-fluorodeoxyuridine monophosphate, is strictly correlated with cancer cell resistance to 5-FU. On this basis we investigated whether TS is a potential target for active specific immunotherapy of human colon carcinoma, which acquires resistance to 5-FU. Three TS-derived epitope peptides which fit defined amino acid consensus motifs for HLA-A2.1 binding were synthesized and investigated for their ability to induce human TS-specific cytotoxic T cell (CTL) responses in vitro. CTL lines specific for each peptide were established by stimulating peripheral blood mononuclear cells (PBMC) from an HLA-A2.1+ healthy donor with autologous dendritic cells loaded with TS peptide. Specific CTL lines showed HLA-A2.1-restricted cytotoxicity in vitro to HLA-A2.1+ target cells pulsed with the specific TS peptide and to HLA-class I matching colon carcinoma target cells over-expressing TS enzyme after exposure to 5-FU. Recognition by CTL lines suggests that these TS peptides may be potential candidates for use in a peptide-based vaccine against 5-FU resistant colon carcinoma.