Thrombospondin-1 plus irinotecan: a novel antiangiogenic-chemotherapeutic combination that inhibits the growth of advanced human colon tumor xenografts in mice

Chemotherapy for the treatment of advanced or metastatic colon cancer, utilizing agents such as 5-fluorouracil (5-FU) and irinotecan (CPT-11), produce a 5-year survival of about 10%. Thus, the identification of new, effective, therapeutic regimens to treat this disease remains critically important. To this end, selected antiangiogenic agents, compounds that inhibit neovascularization, have been shown to produce a modest tumor growth-inhibitory effect with little systemic toxicity. Thus these agents are attractive candidates for use with conventional chemotherapeutic agents to treat this disease. To evaluate this approach, experiments were undertaken to assess the cytotoxic and antineoplastic activity of CPT-11 and the antiangiogenic agent thrombospondin-1 (TSP-1) in the HT-29 model of human colon cancer. These agents were chosen since CPT-11 is a camptothecin analogue efficacious in the treatment of colon cancer and TSP-1 is a human glycoprotein that possess antiangiogenic activity. As expected, in vitro studies revealed that a 5-day exposure to TSP-1 at concentrations up to 130 g/ml was not cytotoxic alone and did not affect the cytotoxicity of CPT-11, or of its active metabolite SN38, in HT-29 cells. Similarly, in human umbilical vein endothelial cells, TSP-1 alone induced only a slight cell growth-inhibitory effect and did not significantly increase the cytotoxicity of either CPT-11 or SN38. The antineoplastic activities of TSP-1 and CPT-11 were assessed in athymic (nude) female mice bearing advanced subcutaneous xenografts of HT-29 cells. Mice received TSP-1 alone (5–40 mg/kg per day) intraperitoneally (i.p.), CPT-11 alone (100–300 mg/kg, i.p.), TSP-1 (10 mg/kg per day) plus CPT-11 (125 mg/kg), or TSP-1 (20 mg/kg per day) plus CPT-11 (150 mg/kg). TSP-1 was injected daily (Monday through Friday) for 4 weeks (20 injections in total) whereas CPT-11 was administered once weekly on days 0, 7, 14 and 21. By day 28, treatment with TSP-1 alone (5, 10 or 20 mg/kg per day) induced a dose-dependent inhibition of xenograft growth. Further, treatment with 10 or 20 mg/kg per day resulted in an average treated tumor size/control tumor size (T/C) on day 28 of 0.68 (range 0.64–0.71) or 0.58 (range 0.54–0.60), respectively. CPT-11 at all doses significantly inhibited tumor growth with an average T/C value of 0.21 (range 0.15–0.27). However, the 250 and 300 mg/kg regimens induced significant toxicity and mortality. When TSP-1 was combined with CPT-11, a significant (P0.05) inhibition of tumor growth also was observed (T/C 0.17, range 0.11–0.20). Importantly, this enhanced tumor growth inhibition was obtained without significant toxicity. The therapeutic implications of these findings are discussed.Abbreviations bFGF Basic fibroblast growth factor - CPT-11 Irinotecan - 5-FU 5-Fluorouracil - HUVEC Human umbilical vein endothelial cells - i.p. Intraperitoneally - SN38 7-Ethyl-10-hydroxy camptothecin - T/C Treated tumor size/control tumor size - TSP-1 Thrombospondin-1 - VEGF Vascular endothelial growth factor This work was supported by the TJ Martell Foundation and Rhode Island Hospital.     

Randomized controlled trial of the efficacy of adjuvant immunochemotherapy and adjuvant chemotherapy for colorectal cancer, using different combinations of the intracutaneous streptococcal preparation OK-432 and the oral pyrimidines 1-hexylcarbamoyl-5-fluorouracil and uracil/tegafur

Background We investigated the efficacy and safety of adjuvant immunochemotherapy and adjuvant chemotherapy for colorectal cancer, using different combinations of the intracutaneous streptococcal preparation OK-432 and the oral pyrimidines 1-hexylcarbamoyl-5-fluorouracil (carmofur, HCFU) and uracil/tegafur (UFT).Methods Patients with stage II, III, or IV (Dukes B, C) colorectal cancer were enrolled and randomly assigned to one of three groups: an immunochemotherapy group (mitomycin C [MMC] + 5-fluorouracil [5-FU] + HCFU + OK-432), a chemotherapy group (MMC + 5-FU + HCFU), and a control group (surgery alone) for those with colon cancer (study 1); and an immunochemotherapy group (MMC + 5-FU + UFT + OK-432), a chemotherapy group (MMC + 5-FU + UFT), and a control group (surgery alone) for those with rectal cancer (study 2).Results A total of 760 patients with colon cancer and 669 patients with rectal cancer were entered into this randomized clinical trial (RCT). The incidence of side-effects was in the order of: immunochemotherapy group chemotherapy group control group in both the cohort of patients with colon cancer and the cohort with rectal cancer. In particular, the frequency of leucopenia and skin disorders was significantly higher than control groups. There were no severe adverse events such as death related to the adjuvant therapy. In both the colon cancer and rectal cancer cohorts, no significant difference in the 5-year survival rate and disease-free survival rate was noted among the three groups.Conclusion The results of an RCT demonstrated that the combination of MMC + 5-FU + HCFU + OK-432 for colon cancer and that of MMC + 5-FU + UFT + OK-432 for rectal cancer could not prolong the survival of patients with surgically resected colorectal cancer, but that both combinations were well tolerated as adjuvant therapy.     

Relationship between in vivo drug exposure of the tumor interstitium and inhibition of tumor cell growth in vitro: a study in breast cancer patients

A novel approach is described to simulate effect site pharmacodynamics of anticancer drugs. This approach is based on (i) the in vivo measurement of unbound, interstitial drug pharmacokinetics (PK) in solid tumor lesions in patients and (ii) a subsequent pharmacodynamic (PD) simulation of the time versus drug concentration profile in an in vitro setting. For this purpose, breast cancer cells (MCF-7) were exposed in vitro to the time versus interstitial tumor concentration profiles of 5-fluorouracil (5-FU) and methotrexate (MTX) from primary breast cancer lesions in patients. This led to a maximal reduction in the viable cell count of 69 on day 4, and of 71 on day 7 for 5-FU and MTX, respectively. This effect was dependent on the initial cell count and was characterized by a high interindividual variability. For 5-FU there was a significant correlation between the maximum antitumor effect and the intratumoral AUC (r=0.82, p=0.0005), whereas no correlation could be shown for MTX (r=0.05, p=0.88). We conclude, that the in-vivo-PK / in-vitro-PD model presented in this study may provide a rational approach for describing and predicting pharmacodynamics of cytotoxic drugs at the target site. Data derived from this approach support the concept that tumor penetration of 5-FU may be a response-limiting event, while the response to MTX may be determined by events beyond interstitial fluid kinetics.     

Phase I/II study of irinotecan, 5-fluorouracil,and <Emphasis Type="Italic">l</Emphasis>-leucovorin combination therapy (modified Saltz regimen) in patients with metastatic colorectal cancer

Background A combination of irinotecan 125mg/m², 5-fluorouracil (5-FU) 500mg/m², and leucovorin (LV) 20mg/m² (Saltz regimen; treatment on days 1, 8, 15, and 22 every 6 weeks) is widely used for the treatment of metastatic colorectal cancer. A modified schedule with chemotherapy on days 1 and 8 of a 21-day cycle was recommended in 2001 because of early treatment-related mortality. We conducted a phase I/II study of this modified Saltz regimen as first-line therapy in Japanese patients with metastatic colorectal cancer to assess the maximum tolerated dose (MTD) and the recommended dose of 5-FU when given with fixed doses of l-LV and irinotecan, and to evaluate the efficacy and the feasibility of this regimen.Methods Irinotecan, 5-FU, and l-LV were administered on days 1 and 8 of a 21-day cycle. Irinotecan 100mg/m² was given intravenously over the course of 90min on day 1, followed by l-LV 10mg/m², and then 5-FU. The dose of 5-FU was escalated from 400mg/m² (level 1) to 500mg/m² (level 2). If neither level met the criteria for the MTD, the recommended dose was defined as level 2, and dose escalation was discontinued, because the maximum approved weekly dose of irinotecan alone in Japan is 100mg/m² and the dose of 5-FU in the original Saltz regimen was 500mg/m².Results One patient had grade 4 neutropenia with fever at level 1, and four patients had grade 3 neutropenia at level 2. There was no treatment-related death. Level 2 did not meet the criteria for the MTD. The relative dose intensities of the first five cycles were 91% for both 5-FU and irinotecan at level 1 and 86% for 5-FU and 93% for irinotecan at level 2. The response rates were 58% for all patients, and 69% for patients at level 2.Conclusion Our results confirm that the modified Saltz regimen is safe and efficacious for Japanese patients. The recommended doses for phase II studies are irinotecan 100mg/m², 5-FU 500mg/m², and l-LV 10mg/m².     

Increased cytotoxicity of low-dose,long-duration exposure to 5-fluorouracil of V-79 cells with hyperthermia

Summary We examined the cytotoxic effects of combined low dose and long exposure to 5-fluorouracil (5-FU) and hyperthermia on Chinese hamster V-79 cells with reference to timing and sequence of administration. The survival rate following hyperthermia at 42°C for 2 h alone was 95.4%, and that after exposure to 1.0 g/ml/5-FU alone for 48 hours, 94.2%. With respect to the combination of 5-FU and heat, the survival rate of cells exposed to hyperthermia at 42°C for 2 h followed by 1.0 g/ml 5-FU treatment for 48 h followed by hyperthermia led to a survival rate of 10%. Flow cytometric analysis of V-79 cells after exposure to 1.0 g/ml 5-FU for 48h revealed an accumulation of cells in the S-phase; the percentage of S-phase exponential growing cells was 65% and the plateau phase was 38%. The former were more sensitive to heat than the latter cells according to the MTT assay. V-79 cells pretreated with 5-FU were more sensitive to hyperthermia than were those not pretreated with 5-FU. Therefore, when 5-FU plus heat is to be used to treat a patient with a malignancy, the sequence of 5-FU followed by hyperthermia may be more effective than the reverse.     

The efficacy of long-term oral chemotherapy with 5′-deoxy-5-fluorouridine and cyclophosphamide for recurrent breast cancer

Background 5-Deoxy-5-fluorouridine (5-DFUR) is a prodrug of 5-fluorouracil (5-FU), which is known to be converted by thymidine phosphorylase (dThdPase). A recent preclinical study revealed that cyclophosphamide (CPA) upregulated dThdPase activity, specifically in tumor cells. The purpose of the present study was to examine the efficacy of long-term administration of 5-DFUR/CPA for patients with recurrent breast cancer.Methods Fifteen breast cancer patients with recurrent tumors entered this study. Ten patients had bone metastasis, five had lung metastasis, and two had liver metastasis. Three patients had multiorgan metastases. All patients had had previous exposure to standard chemotherapy such as CAF (CPA, doxorubicin, and 5-FU) and CMF (CPA, methotrexate, and 5-FU). The patients were orally administered with daily doses of 5-DFUR at 800–1200mg and CPA at 200mg for 2 weeks as induction therapy, followed by 2 weeks rest (one to two cycles). Daily doses of 800mg of 5-DFUR and 100mg of CPA (as maintenance therapy) were continuously administered thereafter. Ten of the 15 patients received the maintenance therapy alone. The treatment was continued for at least 24 months (average, 35.2 months).Results The main findings included a significant decrease in pain in nine patients with bone metastasis, and this effect continued for more than 2 years. As the pain decreased, the patients quality of life (QOL) was improved. Liver metastasis was diminished in two out of two patients. Hematological toxicity of more than grade 3 was recognized in three patients, but only during the induction therapy.Conclusion Oral administration of 5-DFUR/CPA is well tolerated and useful for patients with recurrent breast cancer.     

Influence of truth disclosure on quality of life in cancer patients

Background Whether truth disclosure may harm patients may be critical for the promotion of truth disclosure in patients with cancer. We used the Functional Living Index-Cancer (FLIC) to study the influence of truth disclosure on quality of life (QOL) in cancer patients. Methods. Twenty-three truth-disclosed patients with cancer (TD group) and 21 truth-concealed patients (TC group) were asked to answer 22 FLIC questions at the outpatient clinic. Results were compared with those in 18 patients with irritable bowel syndrome (IBS group) and in 37 patients with other gastrointestinal diseases (OGD group). Results. Average FLIC scores were the same in the TD and IBS groups and in the TC and OGD groups. There were significant differences among the four groups for four FLIC items: Discouraged about life (P = 0.04), Uncomfortable today (P = 0.03), Pain disrupts activity, (P = 0.0003) and How much nausea (P = 0.04). The IBS group had the worst FLIC scores for the former three of these items. Truth disclosure influenced only one FLIC item, in that the TD group was more likely to think that their daily activities were disrupted by pain or discomfort than the TC group (P = 0.01). However, incurability of cancer worsened the score for ten FLIC items, among which incurability was independently associated with the deterioration of FLIC-QOL in terms of Family disruption (P = 0.03) and Cancer-related pain (P = 0.02). Conclusion. Incurability of cancer, not truth disclosure, negatively affects patients' QOL. Thus, if sufficient supportive care is provided particularly to patients with incurable cancer, the truth could be disclosed without fear of being cruel or harming patients.     

左半结肠癌急性梗阻一期切除吻合的安全保证

Objective: Thorough, prompt enteral decompression technique without contamination was developed to ensure safety for emergent colon resection and primary anastomosis. Methods: After isolating the mesentery, the to be resected colon segment was cut at its lower end, then the proximal cut end was put into a plastic bag which was adhered to one side of the operating table. After releasing the clamp, the content could flow into this bag. The operator could squeeze the bowel with two hands by turns, from proximal to farness, and from small bowel to large bowel, until the entire bowel content was fully discharged. Then the upper end of this to be resected colon segment was cut, and was removed together with the plastic bag. Results: 31 cases of left colon cancer with acute obstruction were decompressed with this technique. They all recovered smoothly, without anastomosis fistula. Another 6 cases of hepatic segmentectomy with incidental colonectomy were decompressed with this technique and had the same results. This technique was also used in different kinds of acute small intestinal obstruction and gained satisfactory results. Conclusion: This technique could be considered as the preferable choice for intraoperative enteral decompression.     

Alterations in cellular retinol metabolism contribute to differential retinoid responsiveness in normal human mammary epithelial cells versus breast cancer cells

The present study was undertaken to compare ROH growth responsiveness between normal human mammary epithelial cells (HMECs), estrogen receptor positive (MCF-7) and negative (MDA-MB-231) breast cancer cells, and assess whether this responsiveness is correlated with differences in ROH metabolism, particularly RA synthesis. HMECs were markedly more growth sensitive to a physiological dose of ROH than breast cancer cells, exhibiting a significant decrease in cell number by 48h and >70% decrease by 144h. In comparison, numbers of MCF-7s were only decreased 32% by 144h. MDA-MB-231 cells were not affected. However, HMECs and MCF-7 cells displayed similar growth responsiveness to 1M RA, while MDA-MB-231 cells were minimally affected. Although the initial rates and extent of ROH uptake were comparable among cell types, ROH levels in HMECs progressively decreased to 20% of the peak by 24h and 10% by 72h. In contrast, ROH levels in the cancer cells remained relatively constant through 48h. The decrease in HMEC ROH was attributable to greater metabolism as evidenced by rapid and predominant retinyl ester formation. HMECs also produced 5 times more RA from ROH than MCF-7s and 10 times more than MDA MB-231 cells. Our results demonstrate that normal HMECs are markedly more responsive to the growth inhibitory effects of ROH than breast cancer cells, and that this responsiveness is associated with greater ROH metabolism including greater RA synthesis. These data suggest that altered ROH metabolism may be a factor in breast cancer progression.     

Chemosensitivity and cytokine sensitivity of malignant mesothelioma

Summary Malignant mesothelioma arises in serosal tissues, is locally invasive, and is usually resistant to chemotherapeutic agents used clinically. To determine whether resistance to cytotoxic drugs was an inherent characteristic of mesothelioma cells, we performed in vitro chemosensitivity testing on five fully characterised human malignant mesothelioma cell lines and, for comparison, on three lines representative of clinically drug-resistant solidtissue carcinomas using the MTT (tetrazolium bromide) assay system. Mesothelioma cell lines were intrinsically resistant to eight common antineoplastic drugs, with concentrations that produced a 50% reduction in optical density (IC₅₀ values) for all drugs being equivalent, if not higher, for mesothelioma cell lines as compared with lung and colon carcinoma cell lines. We then investigated the direct anti-mesothelioma activity of recombinant human cytokines with their antineoplastic properties. All five mesothelioma cell lines were resistant to tumour necrosis factor, but they displayed varying degrees of sensitivity to interferons (IFNs). IFN directly inhibited the growth of two of five mesothelioma lines. IFN displayed little activity against four of five mesothelioma lines. The mesothelioma cells that were sensitive to IFN were resistant to IFN, indicating that sensitivity to IFNs is not a genetic characteristic of malignant mesothelioma cells. Significant interactions between cytokines in combination were not observed.     

IFN-β Gene Therapy Induces Systemic Antitumor Immunity Against Malignant Glioma

We previously demonstrated that intratumoral administration of liposomes containing the murine interferon beta (IFN-) gene [lip(pSV2muIFN-)] resulted in stronger growth-inhibitory effect on GL261 (H-2^b) mouse glioma inoculated in brains of syngeneic C57BL/6 mice than conventional exogenous IFN- administration, and histologic evaluation revealed the massive infiltration of T lymphocytes (CD8 > CD4) within the residual tumor. The present study was aimed at determining whether such tumor-infiltrating lymphocytes (TIL) have any tumor-specific cytotoxic effects. Intratumoral administration of lip(pSV2muIFN-) resulted in prolonged survival time and a 50% tumor-free incidence in the mice treated. The surviving animals were subsequently re-challenged with either subcutaneous or intracranial injection of GL261 cells, and no tumors were found to develop over a 50-day period. In vivo depletion of CD8, but not CD4 cells decreased the efficacy of lip(pSV2muIFN-). Specific cytotoxic T lymphocytes (CTL) against GL261 cells were generated from both TIL and spleen cells of the mice treated. The results of flow cytometric analysis and antibody blocking test revealed that the bulk CTL lines thus prepared were T cell receptor (TCR) , CD8 T lymphocytes with H-2^b restriction.These findings suggest that, in addition to direct growth-inhibitory effects by the IFN- gene on the tumor cells, activation of systemic cellular immunity may participate in antitumor effects in vivo, despite the fact that central nervous system is generally regarded as an immunologically privileged site.     

The role of transforming growth factor Β in glioma progression

This review examines the apparently paradoxical conversion of transforming growth factor 's (TGF) regulatory role as a growth inhibitor among normal glial cells to that of a progression factor among glioblastomas (GM). In vitro, TGF functions as an autocrine growth inhibitor of near-diploid gliomas of any grade. In contrast, hyperdiploid glioblastoma multiforme (HD-GM) cultures proliferate in response to TGF, which is mediated by induction of platelet-derived growth factor B chain (PDGF-BB). The dominant hypothesis of TGF's pathogenetic association with malignant transformation has been predicated upon acquisition of resistance to its growth inhibitory effects. However, the lack of obvious correlation with TGF receptor (TR) expression (or loss) between the HD-GM and the TGF-inhibited GM cultures suggests the existence of intrinsically opposed regulatory mechanisms influenced by TGF. The mechanism of conversion might be explained either by the loss of a putative tumor suppressor gene (TSG) which mediates TGF's inhibition of growth or by enhancement of an active oncogenic pathway among the HD-GM. The frequency of mutations within glioma-associated TSG, such as TP53 and RB, suggests that defects in TGF's inhibitory signaling pathway may have analogous effects in the progression to HD-GM, and TGF's conversion to a mitogen. Alternative sites of inactivation which might explain the loss of TGF's inhibitory effect include inactivating mutation/loss of the TR type II, alterations in post-receptor signal transmission or the cyclin/cyclin dependent kinase system which regulates the phosphorylation of pRB. Loss or inactivation of a glial TSG with a consequent failure of inhibition appears to allow TGF's other constitutive effects, such as induction of c-sis, to become functionally dominant. Mechanistically, TGF's conversion from autocrine inhibitor to mitogen promotes 'clonal dominance' by conferring a Darwinian advantage to the hyperdiploid subpopulations through qualitative and quantitative differences in its modulation of PDGF-A and c-sis, with concomitant paracrine inhibition of competing, near-diploid elements. Abbreviations: transforming growth factor (TGF) and receptor (TR); retinoblastoma gene (RB) and protein (pRB); platelet-derived growth factor (PDGF) and receptor (PDGFR); epidermal growth factor (EGF) and receptor (EGFR); fibroblast growth factor (FGF); malignant glioma (MG), astrocytoma (AST), anaplastic astrocytoma (AAST), glioblastoma (GM); hyperdiploid glioblastoma (HD-GM); glioblastoma multiforme (GM); normal rat kidney (NRK); tumor suppressor gene (TSG); loss of heterozygosity (LOH); TP53 wild type (TP53wt); TP53 mutant (TP53m)     

Organochlorines, p53 mutations in relation to breast cancer risk and survival. A Danish cohort-nested case-controls study

Epidemiological studies integrating genetic susceptibility with biological measurements of organochlorine exposure may provide new clues regarding these substances influence on breast cancer etiology. Initial attempts pursuing this avenue has dealt with polymorphisms in the carcinogen-metabolizing enzymes cytochrome P450 (CYPlAl). This study examined if mutations in the tumor suppressor gene p53 affected organochlorine exposure related breast cancer risk and survival. The material consisted of 162 breast cancer cases and 316 matched controls, who had participated, in the Copenhagen City Heart Study (CCHS) between 1976 and 1978. Cases diagnosed between study initiation and 1993 were identified by linkage to the Danish Cancer Registry. The case group served as a cohort in the survival analyses. Information on known and suspected breast cancer risk factors was obtained from CCHS, and the Danish Breast Cancer Cooperative Group provided information on tumor characteristics. Lipid adjusted serum concentrations of selected organochlorines were compared between cases and controls while stratifing by p53 mutation status. A non-significant increased risk of breast cancer was observed in the highest exposure level of dieldrin and polychlorinated biphenyls among women who developed a tumor with mutant p53 (odds ratio (OR)=3.53, 95% confidence interval (CI)=0.79–15.79 and OR=3.00, 95% CI=0.66–13.62). There was no clear difference in overall survival between breast cancer cases with 'wild-type' and mutant p53, although a significant dose-response relationship appeared for dieldrin exposure in tumors with 'wild-type' p53. These preliminary results suggest that p53 mutations may have a modifying effect on at least the breast cancer risk associated with exposures to organochlorines.     

Malignant cells, directors of the malignant process: role of transforming growth factor-beta

Malignant cells survive and thrive by expressing growth and invasion 'programs' that many normal cell types recognize and respond to in 'programmed' patterns. An early event in the molecular evolution of many malignancies loss of response to growth control by transforming growth factor-beta TGF- frequently due to mutation in the type I or type II TGF- receptor or a Smad protein. The malignant cells secrete TFG- that acts on the host to suppress antitumor immune responses, to enhance extracellular matrix production and to augment angiogenesis. These activities resemble those induced by TGF- during embryonic development and account in part for the 'de-differentiated' nature of malignant disease. Clinically, TGF- is often elevated in the plasma of breast cancer patients, lung cancer patients, hepatocellular carcinoma patients, and prostate cancer patients. Preclinically, several breast cancer models and prostate cancer models in vivo have demonstrated a connection between TGF- expression and increased tumorigenicity, increased invasion and drug resistance. In other diseases such as colon, gastric, endometrial, ovarian, and cervical cancers and gliomas and melanoma, loss of response to TGF- as a growth inhibitor and increased expression of TGF- have been associated with malignant conversion and progression. Elevated levels of TGF- are measurable in nude mice bearing a wide variety of human tumor xenografts; thus, these tumor models may serve as useful mimics of the human disease with respect to the TGF- pathway. Cancer cure may be approached by blocking several of the major normal pathways used for tumor growth and survival in combination with cytotoxic therapies.     

Prognostic significance of thymidylate synthase in patients with metastatic colorectal cancer who receive protracted venous infusions of 5-fluorouracil

Background This study was conducted to evaluate the prognostic significance of thymidylate synthase (TS) expression in the tumor tissue of patients with metastatic colorectal cancer (CRC) who received protracted venous infusions of 5-fluorouracil (5-FU).Methods We retrospectively analyzed the prognostic value of TS expression as compared with other clinical prognostic factors in 57 patients with metastatic CRC.Results On univariate analysis, survival was significantly related to TS expression (low vs high; P = 0.0015), alkaline phosphatase (ALP) level (<300 vs 300IU/l; P = 0.0037), performance status (0 or 1 vs 2 or 3; P = 0.0073), and white blood cell count (<10000/mm³ vs 10000/mm³; P = 0.0001), with number of metastatic sites (1 vs 2; P = 0.06) approaching significance. On multivariate analysis, survival was significantly related to TS expression (hazard ratio [HR], 2.97) and ALP level (HR, 2.26).Conclusion In patients with metastatic CRC who received protracted venous infusions of 5-FU, TS expression was related to survival independently of other established clinical prognostic factors.     

Alcohol and colorectal cancer: a case-control study from northern Italy

The role of alcohol consumption in the etiology of colorectal cancer has been investigated in a case-control study conducted from 1985 to 1990 in the northern part of Italy, on 889 cases of colon cancer, 581 cases of rectal cancer, and 2,475 controls admitted to hospital for acute, non-neoplastic, nodigestive disordes. After allowance for age, education, study center, body mass index, and approximate total energy intake, no significant associations between alcohol intake and the risk of cancer of the colon or rectum were found (odds ratios [OR] for 42 drinks/week cf none =1.0 (95 percent confidence interval [CI]=0.8–1.4) and 0.7 (CI=0.5–1.0) for cancer of the colon and rectum, respectively). A significant increase in the risk of colon cancer with increasing alcohol consumption was, however, observed in females (OR for 28 drinks/week cf none = 1.8 (CI=1.1–3.0)). While the results of the present case-control study do not suggest that alcohol plays a role in the etiology of colon or rectum cancer overall, they provide a hint for a weak association between alcohol consumption and colon cancer among females which, because of the similarities with breast cancer, should be evaluated in the context of the possible relationship between colon cancer, alcohol intake, and female hormones.Drs Barra, Franceschi, and Guarneri, are with the Epidemiology Unit, Aviano Cancer Center Aviano, Italy. Dr Franceschi is also with the European Cancer Prevention Organisation (ECP), Epidemiology and Cancer Working Group, Brussels, Belgium. Drs Negri and La Vecchia are with the Mario Negri Institute for Pharmacological Research, Milan, Italy. Dr La Vecchia is also with the Institute of Social and Preventive Medecine, University of Lausanne, Lausanne, Switzerland. Address correspondence to Dr Barra, Epidemiology Unit, Aviano Cancer Center, Via Pedemontana Occ., 33081 Aviano (PN) Italy. Support for this project was contributed by the Italian Association for Research on Cancer and the Italian League against Tumors, Milan and the Italian National Research Council (CNR Applied Project Clinical Applications of Oncological Research).     

Phase I trial of combined chemotherapy with docetaxel, cisplatin, and 5-fluorouracil for patients with locally advanced squamous cell carcinoma of the head and neck

Background This phase I study was designed to determine the maximum tolerated dose (MTD) and toxicities of combination chemotherapy with docetaxel, cisplatin, and 5-fluorouracil (5-FU) in patients with locally advanced squamous cell carcinoma of the head and neck (SCCHN).Methods Patients received two cycles of chemotherapy repeated every 4 weeks. Starting doses (dose level 0) were: docetaxel 60mg/m², cisplatin 60mg/m², and 5-day continuous infusion 5-FU 600mg/m² per day. At least three patients were examined at each dose level before advancing to the next level.Results Nineteen male patients (median age, 59.5 years) were enrolled. Eighteen patients had previously untreated stage III or IV SCCHN and 1 had local relapse, rT4. In the 19 patients, the regimen was well tolerated, with neutropenia as the most common toxicity (grade 3; n = 11; grade 4; n = 1). Dose-limiting toxicity (DLT) was observed at the fifth dose level (docetaxel 70mg/m², cisplatin 70mg/m², 5-FU 750mg/m² per day), when 1 patient developed grade 2 renal toxicity during the first course; another 2 patients had persistent neutropenia. These doses were thus deemed the MTD for the regimen. In the 18 assessable patients, the overall clinical response rate was 94% (17/18 patients) and primary-site complete response (CR) occurred in 4 (22%) patients.Conclusion The MTD of this regimen was docetaxel 70mg/m² on day 1, cisplatin 70mg/m² on day 4, and 5-FU 750mg/m² per day for 5 days. The regimen was safe and generally well-tolerated and demonstrated good efficacy in patients with locally advanced SCCHN.     

Apoptotic DNA Endonuclease (DNase-γ) Gene Transfer Induces Cell Death Accompanying DNA Fragmentation in Human Glioma Cells

Aims: Both the genetic restoration of the apoptotic pathway and the introduction of proapoptotic molecules are now drawing attention. Concerning apoptosis of human glioma cells induced by human interferon- protein, we found that DNA endonuclease (DNase-) acts as an executive molecule. The authors investigated whether gene transfer of this DNase- exerts some therapeutic effects on human glioma cells. Methods: We transduced U251SP, U251MG, and T98G human glioma cells with DNase- gene via multilamellar cationic liposomes, monitored the growth of those cells, and carefully observed the cell-death pattern. Results: DNase- gene transfer resulted in an overexpression of DNase- protein and induced DNA fragmentation in gene-transferred cells. The cytotoxic effect rose with multiple inoculations of the liposome, suggesting a relationship between its expression and the therapeutic effect. Conclusions: These results demonstrate that DNase- gene transfer can induce apoptosis in human glioma cells, indicating its potential to become a future gene therapy strategy.     

Phase I study of CPT-11 and bolus 5-FU/<Emphasis Type="Italic">l</Emphasis>-leucovorin in patients with metastatic colorectal cancer

Background Irinotecan (CPT-11) and bolus 5-fluorouracil (5-FU)/leucovorin (LV) administered weekly for 4 weeks every 42 days (Saltz regimen) is active but substantially toxic in patients with metastatic colorectal cancer (CRC). The efficacy and toxicity of this regimen, however, have not been determined in Japanese patients with metastatic CRC.Methods We investigated the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), and recommended phase II dose (RD) for CPT-11 given i.v. (90-min infusion) and bolus 5-FU plus biologically active l-LV administered weekly for 3 weeks every 28 days (modified Saltz regimen) in Japanese patients with metastatic CRC. Eighteen patients with measurable disease, Eastern Cooperative Oncology Group (ECOG) performance status of 2 or less, and adequate organ functions were enrolled.Results At dose level 2 (CPT-11, 100mg/m²; 5-FU, 400mg/m²; and l-LV, 25mg/body), 1 of 6 patients had DLT (febrile neutropenia). At dose level 3 (CPT-11, 100mg/m²; 5-FU, 500mg/m²; and l-LV, 25mg/body), 2 of 6 patients had DLT (febrile neutropenia and grade 4 neutropenia lasting more than 4 days). To determine whether level 3 was the MTD level, an additional 3 patients were treated at this level, but no DLT was observed. Consequently, 2 of 9 patients had DLT at level 3, this level thus being considered as the RD. At this level, grade 3–4 neutropenia was common but manageable. Nonhematological toxicities were mild. Seven partial responses were observed in the 18 enrolled patients (response rate [RR], 39%), and 8 patients (44%) experienced stable disease.Conclusion This CPT-11/5-FU/l-LV regimen administered weekly for 3 weeks every 28 days has substantial antitumor activity, with manageable toxicities. A multicenter phase II study is currently underway.     

Coexpression of c-kit and stem cell factor in breast cancer results in enhanced sensitivity to members of the EGF family of growth factors

Insulinlike growth factor (IGF)I protects many cell types from apoptosis. As a result, it is possible that IGFIresponsive cancer cells may be resistant to apoptosisinducing chemotherapies. Therefore, we examined the effects of IGFI on paclitaxel and doxorubicininduced apoptosis in the IGFIresponsive breast cancer cell line MCF7. Both drugs caused DNA laddering in a dosedependent fashion, and IGFI reduced the formation of ladders. We next examined the effects of IGFI and estradiol on cell survival following drug treatment in monolayer culture. IGFI, but not estradiol, increased survival of MCF7 cells in the presence of either drug. Cell cycle progression and counting of trypanblue stained cells showed that IGFI was inducing proliferation in paclitaxeltreated but not doxorubicintreated cells. However, IGFI decreased the fraction of apoptotic cells in doxorubicin but not paclitaxeltreated cells. Recent work has shown that mitogenactivated protein kinase (MAPK) and phosphotidylinositol3 (PI3) kinase are activated by IGFI in these cells. PI3 kinase activation has been linked to antiapoptotic functions while MAPK activation is associated with proliferation. We found that IGFI rescue of doxorubicininduced apoptosis required PI3 kinase but not MAPK function, suggesting that IGFI inhibited apoptosis. In contrast, IGFI rescue of paclitaxelinduced apoptosis required both PI3 kinase and MAPK, suggesting that IGFImediated protection was due to enhancement of proliferation. Therefore, IGFI attenuated the response of breast cancer cells to doxorubicin and paclitaxel by at least two mechanisms: induction of proliferation and inhibition of apoptosis. Thus, inhibition of IGFI action could be a useful adjuvant to cytotoxic chemotherapy in breast cancer.