The impact of sodium-glucose cotransporter-2 inhibitors on outcome of patients with diabetes mellitus and colorectal cancer

BACKGROUND AND AIM

Patients with type 2 diabetes mellitus (T2DM) have a higher risk of colorectal cancer (CRC), and those with diagnosed CRC have a poorer prognosis compared with individuals with normal glucose levels. The inhibition of sodium-glucose cotransporter 2 (SGLT2) channels has been associated with a reduction in tumor proliferation in preclinical studies. We aimed to investigate the impact of sodium-glucose cotransporter 2 inhibitors (SGLT2i) on the outcome of T2DM patients with colorectal cancer.

METHODS

We performed a retrospective cohort study comprising adult patients with T2DM and colorectal adenocarcinoma. SGLT2i recipients were matched to non-SGLT2i recipients in a 1:1 ratio based on age, sex, and cancer stage. The primary outcome was overall survival (OS) and progression-free survival (PFS), and the secondary outcomes were previously reported serious adverse events associated with SGLT2i.

RESULTS

We identified 1347 patients with T2DM and colorectal adenocarcinoma, from which 92 patients in the SGLT2i cohort were matched to the non-SGLT2i cohort. Compared to non-SGLT2i recipients, SGLT2i recipients had a higher rate of 5-year OS (86.2% [95% CI: 72.0-93.5] vs 62.3% [95% CI: 50.9-71.8], P = 0.013) and 5-year PFS (76.6% [95% CI: 60.7-86.7] vs 57.0% [95% CI: 46.2-66.4], P = 0.021). In Cox proportional hazard analyses, SGLT2i were associated with a 50-70% reduction in all-cause mortality and disease progression. SGLT2i were not associated with an increased risk of serious adverse events.

CONCLUSION

SGLT2i were associated with a higher rate of survival in T2DM patients with colorectal cancer.

Oral paclitaxel and encequidar in patients with breast cancer: a pharmacokinetic, safety, and antitumor activity study

Background

Paclitaxel is widely used for the treatment of metastatic breast cancer (MBC). However, it has a low oral bioavailability due to gut extrusion caused by P-glycoprotein (P-gp). Oral paclitaxel (oPAC) may be more convenient, less resource-intensive, and more tolerable than its intravenous form. Encequidar (E) is a first-in-class, minimally absorbed, gut-specific oral P-gp inhibitor that facilitates the oral absorption of paclitaxel.

Objectives

To investigate the pharmacokinetics (PK), overall response rate (ORR), and safety of weekly oral paclitaxel with encequidar (oPAC + E) in patients with advanced breast cancer.

Design

This is a multicenter, single-arm, open-label study in six medical centers in Taiwan.

Methods

Patients with advanced breast cancer were administered 205 mg/m2 oPAC and 12.9 mg E for 3 consecutive days weekly for up to 16 weeks. Plasma samples were collected at weeks 1 and 4. PK, ORR, and safety were evaluated.

Results

In all, 28 patients were enrolled; 27 had MBC; 23 had prior chemotherapy; and 14 had ⩾2 lines of prior chemotherapy. PK were evaluable in 25 patients. Plasma paclitaxel area under the curve (AUC)(0-52 h) at week 1 (3419 ± 1475 ng h/ml) and week 4 (3224 ± 1150 ng h/ml) were equivalent. Best overall response in 28 evaluable patients was partial response (PR) in 11 (39.3%), 13 (46.4%) stable disease (SD), and 1 (3.6%) with progressive disease (PD). No patient achieved complete response (CR). The clinical benefit rate (CR + PR + SD) was 85.7%. Major adverse events among the 28 treated patients were grade 3 neutropenia (25%), grade 4 neutropenia (18%), with febrile neutropenia in 4%, and grade 3 diarrhea (4%). No treatment-related deaths occurred. Grade 2 peripheral neuropathy occurred in 1 (4%) patient and grade 3 peripheral neuropathy in 1 (4%) patient.

Conclusions

oPAC + E produced a consistent therapeutic plasma paclitaxel exposure during treatment. There was a high rate of radiologically assessed clinical benefit, and a low rate of neurotoxicity which may provide advantages over IV paclitaxel.

Registration

ClinicalTrials.gov Identifier: NCT03165955.

Effectiveness of Stereotactic Ablative Radiotherapy for Systemic Therapy Respondents with Inoperable Pulmonary Oligometastases and Oligoprogression

Stereotactic ablative radiotherapy (SABR) may improve survival in patients with inoperable pulmonary oligometastases. However, the impact of pulmonary oligometastatic status after systemic therapy on SABR outcomes remains unclear. Hence, we investigated the outcomes of SABR in 45 patients with 77 lung tumors and the prognostic value of pulmonary oligoprogression. Eligibility criteria were pulmonary oligometastases (defined as ≤5 metastatic lung tumors), controlled extrapulmonary disease (EPD) after front-line systemic therapy, SABR as primary local treatment for inoperable pulmonary metastases, and consecutive imaging follow-up. Oligometastatic lung tumor was classified into controlled or oligoprogressive status. Overall survival (OS), in-field progression-free survival (IFPFS), out-field progression-free survival (OFPFS), and prognostic variables were evaluated. With 21.8 months median follow-up, the median OS, IFPFS, and OFPFS were 28.3, not reached, and 6.5 months, respectively. Two-year OS, IFPFS, and OFPFS rates were 56.0%, 74.2%, and 17.3%, respectively. Oligoprogressive status (p = 0.003), disease-free interval < 24 months (p = 0.041), and biologically effective dose (BED₁₀) < 100 Gy (p = 0.006) were independently associated with inferior OS. BED₁₀ ≥ 100 Gy (p = 0.029) was independently correlated with longer IFPFS. Oligoprogressive status (p = 0.017) and EPD (p = 0.019) were significantly associated with inferior OFPFS. Grade ≥ 2 radiation pneumonitis occurred in four (8.9%) patients. Conclusively, SABR with BED₁₀ ≥ 100 Gy could provide substantial in-field tumor control and longer OS for systemic therapy respondents with inoperable pulmonary oligometastases. Oligoprogressive lung tumors exhibited a higher risk of out-field treatment failure and shorter OS. Hence, systemic therapy should be tailored for patients with oligoprogression to reduce the risk of out-field treatment failure. However, in the absence of effective systemic therapy, SABR is a reasonable alternative to reduce resistant tumor burden.

Evaluation of combination treatment with DS-1205c, an AXL kinase inhibitor, and osimertinib in metastatic or unresectable EGFR-mutant non-small cell lung cancer: results from a multicenter, open-label phase 1 study

The objective of this study was to evaluate the safety and tolerability of DS-1205c, an oral AXL-receptor inhibitor, in combination with osimertinib in metastatic or unresectable EFGR-mutant non-small cell lung cancer (NSCLC) patients who developed disease progression during EGFR tyrosine kinase inhibitor (TKI) treatment. An open-label, non-randomized phase 1 study was conducted in Taiwan, in which 13 patients received DS-1205c monotherapy at a dosage of 200, 400, 800, or 1200 mg twice daily for 7 days, followed by combination treatment with DS-1205c (same doses) plus osimertinib 80 mg once daily in 21-day cycles. Treatment continued until disease progression or other discontinuation criteria were met. At least one treatment-emergent adverse event (TEAE) was reported in all 13 patients treated with DS-1205c plus osimertinib; with ≥ 1 grade 3 TEAE in 6 patients (one of whom also had a grade 4 increased lipase level), and 6 patients having ≥ 1 serious TEAE. Eight patients experienced ≥ 1 treatment-related AE (TRAE). The most common (2 cases each) were anemia, diarrhea, fatigue, increased AST, increased ALT, increased blood creatinine phosphokinase, and increased lipase. All TRAEs were non-serious, with the exception of an overdose of osimertinib in 1 patient. No deaths were reported. Two-thirds of patients achieved stable disease (one-third for > 100 days), but none achieved a complete or partial response. No association between AXL positivity in tumor tissue and clinical efficacy was observed. DS-1205c was well-tolerated with no new safety signals in patients with advanced EGFR-mutant NSCLC when administered in combination with the EFGR TKI osimertinib. ClinicalTrials.gov ; NCT03255083.

Chemopreventive effects of Xiang Sha Liu Jun Zi Tang on paclitaxel-induced leucopenia and neuropathy in animals

Paclitaxel frequently induces peripheral neuropathy and myelosuppression during cancer treatment. According to the National Health Insurance Research Database of Taiwan, traditional Chinese medicine doctors widely use Xiang Sha Liu Jun Zi Tang (XSLJZT) to treat breast cancer patients who have received paclitaxel. We explored the combined therapeutic effects of XSLZJT with paclitaxel. XSLJZT did not exhibit significant cytotoxic effects on P388-D1 cells; however, the combination of XSLJZT (100 and 500 mg/kg) with paclitaxel prolonged the survival rate in P388–D1 tumor-bearing mice compared to paclitaxel-only. In addition, XSLJZT was found to enhance white blood cells (WBC) counts and promote leukocyte rebound in paclitaxel-induced leukopenia in mice. XSLJZT also reduced paclitaxel-induced mechanical pain and inhibited c-Fos protein expression in the L4-6 spinal cords of Wistar rats. Moreover, paclitaxel-induced shortening of the nerve fibers of dorsal root ganglion cells was ameliorated by pre-treatment with XSLJZT. Therefore, we suggest that XSLJZT could be used as an adjunct for cancer patients, as the formula could decrease paclitaxel-induced neuropathy and myelosuppression.

Impact of sodium-glucose cotransporter-2 inhibitors on heart failure and mortality in patients with cancer

OBJECTIVES

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) reduce heart failure (HF) in at-risk patients and may possess antitumour effects. We examined the effect of SGLT2i on HF and mortality among patients with cancer and diabetes.

METHODS

This was a retrospective propensity score-matched cohort study involving adult patients with type 2 diabetes mellitus diagnosed with cancer between January 2010 and December 2021. The primary outcomes were hospitalisation for incident HF and all-cause mortality. The secondary outcomes were serious adverse events associated with SGLT2i.

RESULTS

From a total of 8640 patients, 878 SGLT2i recipients were matched to non-recipients. During a median follow-up of 18.8 months, SGLT2i recipients had a threefold lower rate of hospitalisation for incident HF compared with non-SGLT2i recipients (2.92 vs 8.95 per 1000 patient-years, p=0.018). In Cox regression and competing regression models, SGLT2i were associated with a 72% reduction in the risk of hospitalisation for HF (HR 0.28 (95% CI: 0.11 to 0.77), p=0.013; subdistribution HR 0.32 (95% CI: 0.12 to 0.84), p=0.021). The use of SGLT2i was also associated with a higher overall survival (85.3% vs 63.0% at 2 years, p<0.001). The risk of serious adverse events such as hypoglycaemia and sepsis was similar between the two groups.

CONCLUSIONS

The use of SGLT2i was associated with a lower rate of incident HF and prolonged overall survival in patients with cancer with diabetes mellitus.

The incidence and risk of cardiovascular events associated with immune checkpoint inhibitors in Asian populations

OBJECTIVES

Immune checkpoint inhibitors are associated with adverse cardiovascular events. However, there are no data characterizing cardiovascular events among Asians on immune checkpoint inhibitors. We aim to determine the incidence and risk of cardiac events associated with immune checkpoint inhibitors in an Asian population.

METHODS

We performed a retrospective, propensity score-matched cohort study at two tertiary referral centers in Taiwan. Immune checkpoint inhibitor users were matched with non-immune checkpoint inhibitor users based on predetermined clinical variables. The primary outcome was major adverse cardiovascular events, defined as a composite of myocardial infarction, ischemic stroke, acute peripheral occlusive disease, pulmonary embolism, deep venous thrombosis, heart failure, pericardial disease, myocarditis, cardiac arrhythmias and conduction block.

RESULTS

Between January 2010 and November 2021, 868 immune checkpoint inhibitor users were matched 1:1 with non-immune checkpoint inhibitor users. Among immune checkpoint inhibitor users, 67 (7.7%) patients developed major adverse cardiovascular events. During a median follow-up period of 188 days, the incidence rate of major adverse cardiovascular events for immune checkpoint inhibitor and non-immune checkpoint inhibitor users was 94.8 and 46.2 per 1000 patient-years, respectively, resulting in an incidence rate ratio of 2.1 [95% confidence interval: 1.5-2.9]. In multivariate Cox proportional hazard models, immune checkpoint inhibitor users had a 60% increased risk for major adverse cardiovascular events [hazard ratio, 1.6 (95% confidence interval: 1.1-2.3)]. Immune checkpoint inhibitors use was independently associated with increased risk of ischemic stroke [hazard ratio, 3.0 (95% confidence interval: 1.0-9.0)] and pulmonary embolism [hazard ratio, 5.5 (95% confidence interval: 1.4-21.3)]. In multivariate logistic regression analysis, age > 65, metastatic disease, hypertension and baseline platelet-to-lymphocyte ratio < 180 were risk factors for major adverse cardiovascular events.

CONCLUSIONS

Among Asians, immune checkpoint inhibitors were associated with an increased risk of major adverse cardiovascular events, particularly ischemic stroke and pulmonary embolism.

Efficacy of Aumolertinib (HS-10296) in Patients With Advanced EGFR T790M+ NSCLC: Updated Post-National Medical Products Administration Approval Results From the APOLLO Registrational Trial

INTRODUCTION

Aumolertinib (formerly almonertinib; HS-10296) is a novel third-generation EGFR tyrosine kinase inhibitor (TKI) with revealed activity against EGFR-sensitizing mutations and EGFR T790M mutation.

METHODS

Patients with locally advanced or metastatic NSCLC who developed an EGFR T790M mutation after progression on first- or second-generation EGFR TKI therapy were enrolled in this registrational phase 2 trial of aumolertinib at 110 mg orally once daily (NCT02981108). The primary end point was objective response rate (ORR) by independent central review.

RESULTS

A total of 244 patients with EGFR T790M-positive NSCLC were enrolled. The ORR by independent central review was 68.9% (95% confidence interval [CI]: 62.6-74.6). The disease control rate was 93.4% (95% CI: 89.6-96.2). The median duration of response was 15.1 months (95% CI: 12.5-16.6). The median progression-free survival was 12.4 months (95% CI: 9.7-15.0). Among 23 patients with assessable central nervous system (CNS) metastases, the CNS-ORR and CNS-disease control rate were 60.9% (95% CI: 38.5-80.3) and 91.3% (95% CI: 72.0-98.9), respectively. The median CNS-duration of response was 12.5 months (95% CI: 5.6-not reached). Treatment-related adverse events of more than or equal to grade 3 occurred in 16.4% of the patients, with the most common being increased blood creatine phosphokinase level (7%) and increased alanine aminotransferase level (1.2%). The relative dose density of aumolertinib was 99.2% in this study.

CONCLUSIONS

Aumolertinib is an effective and well-tolerated third-generation EGFR TKI for patients with EGFR T790M-positive advanced NSCLC after disease progression on first- and second-generation EGFR TKI therapy. On the basis of these findings, aumolertinib was approved in the People's Republic of China for patients positive for EGFR T790M NSCLC.

A Phase II Clinical Trial on the Combination Therapy of PHY906 Plus Capecitabine in Hepatocellular Carcinoma

LESSONS LEARNED

A PHY906 and capecitabine combination could be effective as a salvage therapy for patients with hepatocellular carcinoma (HCC) previously treated with multiple systemic therapies. This traditional Chinese medicine formulation can work with Western cancer chemotherapeutic agents to improve clinical outcomes or alleviate side effects for patients with advanced HCC.

BACKGROUND

This study aimed to evaluate efficacy and safety of capecitabine combined with a PHY906 (a pharmaceutical-grade formulation of four traditional Chinese herbs) in the treatment of advanced hepatocellular carcinoma (HCC) in Asian patients who were positive for hepatitis B virus (HBV).

METHODS

This study was an open-label, phase II safety and efficacy clinical trial of PHY906 and capecitabine in patients with advanced HCC. Patients received 750 mg/m2 capecitabine b.i.d. 14 days plus 800 mg of PHY906 b.i.d. on days 1-4 and days 8-11 every 21-day cycle. The primary endpoint was 6-month survival rate, and secondary endpoints were progression-free survival, overall survival, disease control rate, and safety.

RESULTS

Thirty-nine subjects completed the study with a 46.2% stable disease rate. The median progression-free survival was 1.5 months, and median overall survival (mOS) was 6 months with a 51.3% 6-month survival rate. The most common adverse events included lower hemoglobin, diarrhea, pain, abdomen (not otherwise specified), fatigue, increased aspartate aminotransferase, and bilirubin. Patients who (a) had not received previous chemotherapies or targeted therapy or (b) had lower starting alpha-fetoprotein (AFP) levels or (c) had HBV infection showed better clinical outcome.

CONCLUSION

Our data showed that PHY906 increases the therapeutic index of capecitabine by enhancing its antitumor activity and reduces its toxicity profile in advanced HCC.

Phase I Dose-Escalation Study of SCB01A, a Microtubule Inhibitor with Vascular Disrupting Activity, in Patients with Advanced Solid Tumors

LESSONS LEARNED

SCB01A is a novel microtubule inhibitor with vascular disrupting activity. This first-in-human study demonstrated SCB01A safety, pharmacokinetics, and preliminary antitumor activity. SCB01A is safe and well tolerated in patients with advanced solid malignancies with manageable neurotoxicity.

BACKGROUND

SCB01A, a novel microtubule inhibitor, has vascular disrupting activity.

METHODS

In this phase I dose-escalation and extension study, patients with advanced solid tumors were administered intravenous SCB01A infusions for 3 hours once every 21 days. Rapid titration and a 3 + 3 design escalated the dose from 2 mg/m² to the maximum tolerated dose (MTD) based on dose-limiting toxicity (DLT). SCB01A-induced cellular neurotoxicity was evaluated in dorsal root ganglion cells. The primary endpoint was MTD. Safety, pharmacokinetics (PK), and tumor response were secondary endpoints.

RESULTS

Treatment-related adverse events included anemia, nausea, vomiting, fatigue, fever, and peripheral sensorimotor neuropathy. DLTs included grade 4 elevated creatine phosphokinase (CPK) in the 4 mg/m² cohort; grade 3 gastric hemorrhage in the 6.5 mg/m² cohort; grade 2 thromboembolic event in the 24 mg/m² cohort; and grade 3 peripheral sensorimotor neuropathy, grade 3 elevated aspartate aminotransferase, and grade 3 hypertension in the 32 mg/m² cohort. The MTD was 24 mg/m² , and average half-life was ~2.5 hours. The area under the curve-dose response relationship was linear. Nineteen subjects were stable after two cycles. The longest treatment lasted 24 cycles. SCB01A-induced neurotoxicity was reversible in vitro.

CONCLUSION

The MTD of SCB01A was 24 mg/m² every 21 days; it is safe and tolerable in patients with solid tumors.

Safety, Efficacy, and Pharmacokinetics of Almonertinib (HS-10296) in Pretreated Patients With EGFR-Mutated Advanced NSCLC: A Multicenter, Open-label, Phase 1 Trial

INTRODUCTION

Almonertinib (HS-10296) is a novel, third-generation EGFR tyrosine kinase inhibitor (EGFR TKI) that targets both EGFR-sensitizing and T790M resistance mutations. This first-in-human trial aimed to evaluate the safety, efficacy, and pharmacokinetics of almonertinib in patients with locally advanced or metastatic EGFR mutation-positive NSCLC that had progressed after pevious EGFR TKI therapy.

METHODS

This phase 1, open-label, multicenter clinical trial (NCT0298110) included dose-escalation (55, 110, 220, and 260 mg) and dose-expansion cohorts (55, 110, and 220 mg) with once daily oral administration of almonertinib. In each expansion cohort, tumor biopsies were obtained for the determination of EGFR T790M status. The safety, tolerability, antitumor activity, and pharmacokinetics of almonertinib were evaluated.

RESULTS

A total of 120 patients (26 patients in the dose-escalation cohort and 94 patients in the dose-expansion cohort) were enrolled. The maximum tolerated dose was not defined in the dose-escalation phase; the 260 mg regimen was not further evaluated in the dose-expansion phase owing to safety concerns and saturation of exposure. The most common treatment-related grade greater than or equal to 3 adverse events were increased blood creatine phosphokinase (10%) and increased alanine aminotransferase (3%). Among 94 patients with the EGFR T790M mutation in the dose-expansion cohort, the investigator-assessed objective response rate and disease control rate were 52% (95% confidence interval [CI]: 42-63) and 92% (95% CI: 84-96), respectively. Median progression-free survival was 11.0 months (95% CI: 9.5-not reached) months.

CONCLUSIONS

Almonertinib is safe, tolerable and effective for patients with locally advanced or metastatic NSCLC harboring the EGFR T790M mutation who were pretreated with EGFR TKIs.

Two first-in-human studies of xentuzumab, a humanised insulin-like growth factor (IGF)-neutralising antibody, in patients with advanced solid tumours

BACKGROUND

Xentuzumab, an insulin-like growth factor (IGF)-1/IGF-2-neutralising antibody, binds IGF-1 and IGF-2, inhibiting their growth-promoting signalling. Two first-in-human trials assessed the maximum-tolerated/relevant biological dose (MTD/RBD), safety, pharmacokinetics, pharmacodynamics, and activity of xentuzumab in advanced/metastatic solid cancers.

METHODS

These phase 1, open-label trials comprised dose-finding (part I; 3 + 3 design) and expansion cohorts (part II; selected tumours; RBD [weekly dosing]). Primary endpoints were MTD/RBD.

RESULTS

Study 1280.1 involved 61 patients (part I: xentuzumab 10-1800 mg weekly, n = 48; part II: 1000 mg weekly, n = 13); study 1280.2, 64 patients (part I: 10-3600 mg three-weekly, n = 33; part II: 1000 mg weekly, n = 31). One dose-limiting toxicity occurred; the MTD was not reached for either schedule. Adverse events were generally grade 1/2, mostly gastrointestinal. Xentuzumab showed dose-proportional pharmacokinetics. Total plasma IGF-1 increased dose dependently, plateauing at ~1000 mg/week; at ≥450 mg/week, IGF bioactivity was almost undetectable. Two partial responses occurred (poorly differentiated nasopharyngeal carcinoma and peripheral primitive neuroectodermal tumour). Integration of biomarker and response data by Bayesian Logistic Regression Modeling (BLRM) confirmed the RBD.

CONCLUSIONS

Xentuzumab was well tolerated; MTD was not reached. RBD was 1000 mg weekly, confirmed by BLRM. Xentuzumab showed preliminary anti-tumour activity.

CLINICAL TRIAL REGISTRATION

NCT01403974; NCT01317420.

A phase I dose escalation study of SCB01A, a micro-tubular inhibitor with vascular disrupting activity, in patients with advanced solid tumors refractory to standard therapy

2531

Background: SCB01A is a novel anti-microtubular agent with vascular disrupting activity. The Phase I study aimed to determine the dose-limiting toxicity (DLT), maximum tolerated dose (MTD), safety, and pharmacokinetic (PK) profiles of SCB01A in patients with advanced solid tumor. Methods: This was an open-label, phase I clinical trial with a rapid titration followed by a 3 x 3 study design. Eligible patients would receive a 3-hr intravenous infusion of SCB01A, every 21 days as one cycle. All adverse events were classified according to the CTCAE V4.0. DLT was defined as the occurrence of grade 3 with complications and grade 4 hematoloigcal, or ≥grade 3 non-hematological toxicities. Results: From June 2011 to November 2015, a total of 33 eligible patients were enrolled to eight dose levels: 2 mg/m2 (n = 1), 3 mg/m2 (n = 1), 4 mg/m2 (n = 6), 6.5 mg/m2 (n = 9, with 3 additional subjects were recruited for safety concern), 10 mg/m2 (n = 3), 16 mg/m2 (n = 3), 24 mg/m2 (n = 6) and 32 mg/m2 (n = 4). Six episodes of DLTs were observed in 5 patients (each one in dose levels of 4/6.5/24 mg/m2 and two in dose level of 32 mg/m2), including grade 4 blood creatine phosphokinase elevation (4 mg/m2), grade 3 gastric hemorrhage (6.5 mg/m2), grade 2 venous thrombosis (24 mg/m2), grade 3 peripheral neuropathy manifested as weakness of lower limbs, grade 3 aspartate aminotransferase elevation, and grade 3 hypertension (32 mg/m2). The MTD was determined to be 24 mg/m2. Pharmacokinetic profiles revealed a linear AUC-dose response with an average elimination half-life (t1/2) of 2.5 hours. Partial response was observed in one subject with buccal cancer. A total of 57.6% (19/33) subjects had stable disease for at least 2 cycles. Conclusions: SCB01A is safe and tolerable in patients with solid tumor. The MTD of SCB01A is 24 mg/m2 every 21 days, which deserves further development. Clinical trial information: NCT011159522.

Effects of Dang-Gui-Bu-Xue-Tang, an herbal decoction, on iron uptake in iron-deficient anemia

Dang-Gui-Bu-Xue-Tang (DBT), a combination of Angelicae Sinensis Radix and Astragali Radix, is a widely used herbal decoction in traditional Chinese medicine primarily to promote or invigorate the “blood”. In this study, we explored this ancient formulation and provide evidence of its blood-toning properties. We used the improvement iron uptake as promote or invigorate the “blood” indicator. Ferritin formation of Caco-2 cells in vitro assay and diet-induced anemia (DIA) in rat model were used to prove its improvement iron uptake and ameliorating effects. Finally, the iron–DBT interactions were measured by iron-binding assay. We first demonstrated DBT increased uptake of ferrous iron through the biosynthesis of ferritin by Caco-2 cells and determined which complementary treatment would provide optimum results. Thereafter, effects of the treatment on improving the bioavailability of absorbed iron in the form of hemoglobin (Hb) were established using a DIA-animal model. The results showed that DBT slightly improved Hb levels compared with the baseline Hb and pretreatment with DBT for 2 hours prior to supplementation with ferrous sulfate provided the greatest gain in Hb levels in DIA rats. However, DBT and ferrous sulfate were co-treated with Caco-2 cell or DIA rats, the ferritin formation and Hb levels both were decreased. In iron-binding assay, the DBT extract influenced the free Fe(II) type in the FeSO₄ solution. Therefore, we suggest that complementary treatment with DBT and iron supplementation can have a strong ameliorating effect on iron-deficiency anemia in clinical settings, but needs a 2-hour interval of DBT administration prior to ferrous sulfate treatment.

Phase I dose-escalation study of sorafenib plus S-1 in refractory solid tumors

745

Background: S-1 is a new oral fluoropyrimidine-derived combo and has been shown activity in patients with various cancers in phase II/III studies. Sorafenib is an oral multikinase inhibitor with anti-proliferative and anti-angiogenesis activities and has been approved for the first-line treatment of advanced HCC, RCC and radioactive iodine-resistant thyroid cancer. In xenograft mouse models, sorafenib showed its activity to enhance the cytotoxicity of chemotherapeutic agents. Therefore, a phase I dose-escalation study to determine the dose-limiting toxicity and maximum dose of S-1 in combination with standard dosing of sorafenib in patients with refractory solid tumors was conducted. Methods: Eligible patients would receive escalating dose (30, 35 and 40 mg/m2, twice daily) of S-1 in a standard 3+3 phase I study design. Treatment was consisted of continuous sorafenib 400 mg bid plus S-1 30-40mg/m2 bid, D1-14, every 21 days per cycle. DLTs were assessed during the first two cycles of treatment, and treatment would be continued until disease progression, the occurrence of unacceptable toxicity or consent withdrawal. Results: A total of 13 patients were included, 7 in 30 mg/m2 dose level and 6 in 35 mg/m2 dose level. DLT occurred in 2 of 6 patients with 35 mg/m2 twice daily, manifested as grade 3 skin rash and prolonged grade 2 hand-foot-skin reaction in one each; while there was no DLT observed in 30 mg/m2 cohort. Seven patients achieved durable tumor control, included one pancreatic neuroendocrine tumor patient who had a sustained PR for 27.9 months, and durable stable diseases (>6 months of progression-free survival) in 3 out of 4 colorectal cancer patients, 2 of 2 biliary tract cancer patients and 1 of 2 pancreatic cancer patients. Conclusions: The recommended dose of S-1 in this combination was 30mg/m2 bid. Preliminary results suggested sorafenib/S-1 combination is feasible and deserves for further exploration in refractory advanced gastrointestinal tract cancers. Clinical trial information: NCT01128998.

Phase I study of nanoliposomal irinotecan (PEP02) in advanced solid tumor patients

Purpose

To define the dose-limiting toxicity (DLT), maximum tolerated dose (MTD) and pharmacokinetics (PK) of PEP02, a novel liposome-encapsulated irinotecan, in patients with advanced refractory solid tumors.

Methods

Patients were enrolled in cohorts of one to three to receive escalating dose of PEP02 in a phase I trial. PEP02, from 60 to 180 mg/m², was given as a 90-min intravenous infusion, every 3 weeks.

Results

A total of 11 patients were enrolled into three dose levels: 60 (one patient), 120 (six patients) and 180 mg/m² (four patients). DLT was observed in three patients, one at 120 mg/m² (grade 3 catheter-related infection) and two at 180 mg/m² (grade 4 neutropenia lasting for >3 days in one, grade 4 hematological toxicities and grade 4 diarrhea in the other). MTD was determined as 120 mg/m². Comparing with those after free-form irinotecan in the literature, the dose-normalized PK of SN-38 (the active metabolite) after PEP02 was characterized by lower C_max, prolonged terminal half-life and higher AUC but with significant inter-individual variation. One patient who died of treatment-related toxicity had significantly higher C_max and AUC levels of SN-38 than those of the other three patients at 180 mg/m². Post hoc pharmacogenetic study showed that the patient had a combined heterozygosity genotype of UGT1A1*6/*28. Two patients had objective tumor response.

Conclusions

PEP02 apparently modified the PK parameters of irinotecan and SN-38 by liposome encapsulation. The MTD of PEP02 monotherapy at 3-week interval is 120 mg/m², which will be the recommended dose for future studies.

Concurrent chemoradiotherapy with cetuximab plus twice-weekly paclitaxel and cisplatin followed by esophagectomy for locally advanced esophageal squamous cell carcinoma

4099

Background: We investigated the efficacy and safety of adding cetuximab to twice-weekly paclitaxel/cisplatin-based concurrent chemoradiotherapy (CCRT), followed by surgery, for patients with locally advanced esophageal squamous cell carcinoma (ESCC). Methods: Patients with locally advanced ESCC (T3N0-1M0 or T1-3N1M0 or M1a by AJCC 2002) were treated with paclitaxel (35 mg/m2 1 h D1, 4/wk), cisplatin (15 mg/m2 1 h D2, 5/wk), cetuximab (400 mg/m2 2 h D-5, then 250 mg/m21 h D3/wk) and radiotherapy (2 Gy D1-5/wk). The feasibility of esophagectomy was evaluated for all patients at the accumulated radiation dose of 40 Gy. If esophagectomy was not feasible, CCRT was continued to a radiation dose of 60-66 Gy. Results: 66 patients were enrolled between Oct 2008 and Jun 2010, and 61 (94%) of them had T3N1M0 or M1a tumors by endoscopic ultrasonographic staging. All patients received CCRT to 40 Gy. Forty-three patients underwent surgery, and 17 patients continued definitive CCRT to 60-66 Gy. Of the scheduled doses of paclitaxel, cisplatin, and cetuximab, 80%, 79%, and 99% were given, respectively. The most common grade 3/4 toxic effects were leukopenia (51%), neutropenia (15%), esophagitis (19%), and infection (12%). The pathological complete response rate was 24% (intent-to-treat, 16/66) (95% confidence interval: 13-35%) and 37% (who underwent resection, 16/43). At the median follow-up of 34.6 months, the median progression-free (PFS) and overall survivals were 21.6 and 33.9 months, respectively. No KRAS codon 12/13 mutations were identified in 47 tumor samples. The median PFS for patients with two, one, and no adverse tumor biomarkers (Tau+, ERCC1+, pEGFR-) (n = 40) was 12.3 months, 27.6 months, and greater than 33.6 months, respectively (p = .087). Conclusions: Adding cetuximab to twice-weekly paclitaxel/cisplatin-based CCRT prior to esophagectomy is an active and tolerable treatment for locally advanced ESCC. Clinical trial information: NCT01034189. [Table: see text]

Phase I study of biweekly liposome irinotecan (PEP02, MM-398) in metastatic colorectal cancer failed on first-line oxaliplatin-based chemotherapy

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Background: PEP02 (MM-398) is a nanoliposomal formulation of irinotecan (CPT-11) that has improved pharmacokinetics (PK) and tumor distribution of CPT-11 and its active metabolite, SN-38. PEP02 single agent q3w has shown preliminary efficacy and safety in Phase II pancreatic and gastric cancer studies. Since irinotecan is approved for metastatic colorectal cancer (mCRC) and biweekly regimens are widely used, the aims of this study are to determine the maximum tolerated dose (MTD), characterize the PK and pharmacogenetics (PGx), and explore the efficacy of PEP02 q2w in mCRC.

Methods: Patients (pts) with disease progression after 1st-line oxaliplatin-based chemotherapy, ECOG PS 0-1, and without prior exposure to irinotecan were eligible. PEP02 was given on day 1 and 15 of each 28 day treatment cycle. The starting dose was 80 mg/m2 and escalated by 10 mg/m2 to the target dose of 100 mg/m2. PK was evaluated during the 1st cycle and the tumor response was assessed by RECIST.

Results: A total of 18 pts (M/F 9/9; median age 57.5) were enrolled, with 6 at each dose level. Dose-limiting toxicity manifested as G3 diarrhea was observed in one pt per dose level. The target dose of 100 mg/m2 was determined to be the MTD. Nine pts had dose delayed (4, 3, 2 at 80, 90, 100 mg/m2), mostly because of neutropenia. The PK and PGx are being analysed. As of August 2011, there are 3 pts still on study treatment and 17 pts evaluable for tumor response. Four pts (2 at 80 mg/m2, 1 each at 90 and 100 mg/m2) showed partial response (3 after 2 cycles and 1 after 8 cycles) and 8 pts (3 each at 80 and 90 mg/m2, 2 at 100 mg/m2) maintained stable disease for at least 2 cycles, which resulted in a response rate (RR) of 23.5% and a disease control rate (DCR) of 70.6%. Current median progression-free survival (PFS) is 4 months and 8 pts (47%) had PFS ≥ 6 months.

Conclusions: The MTD of biweekly PEP02 is 100 mg/m2. As a 2nd-line monotherapy after oxaliplatin-based chemotherapy, the efficacy results indicate the potential benefit of PEP02 for mCRC (FOLFIRI-1 achieved only 4% RR, 34% DCR, and 2.5 months PFS in FOLFOX pretreated pts). A randomized Phase II study evaluating PEP02 plus 5-FU/LV (FUPEP regimen) vs. FOLFIRI is currently ongoing in France.

Combination of arsenic trioxide and BCNU synergistically triggers redox-mediated autophagic cell death in human solid tumors

Arsenic trioxide (As(2)O(3)) is an effective treatment for relapsed or refractory acute promyelocytic leukemia (APL). After the discovery of As(2)O(3) as a promising treatment for APL, several studies investigated the use of As(2)O(3) as a single agent in the treatment of solid tumors; however, its therapeutic efficacy is limited. Thus, the systematic study of the combination of As(2)O(3) with other clinically used chemotherapeutic drugs to improve its therapeutic efficacy in treating human solid tumors is merited. In this study, we demonstrate for the first time, using isobologram analysis, that As(2)O(3) exhibits a synergistic interaction with N,N'-bis(2-chloroethyl)-N-nitrosourea (BCNU). The synergistic augmentation of the cytotoxicity of As(2)O(3) with BCNU is in part through the autophagic cell death machinery in human solid tumor cells. As(2)O(3) and BCNU in combination produce enhanced cytotoxicity via the depletion of reduced glutathione (GSH) and augmentation of reaction oxygen species (ROS) production. Further analysis indicated that the extension of GSH depletion by this combined regimen occurs through the inhibition of the catalytic activity of glutathione reductase. Blocking ROS production with antioxidants or ROS scavengers effectively inhibits cell death and autophagy formation, indicating that redox-mediated autophagic cell death involves the synergism of As(2)O(3) with BCNU. Taken together, this is the first evidence that BCNU could help to extend the therapeutic spectrum of As(2)O(3). These findings will be useful in designing future clinical trials of combination chemotherapy with As(2)O(3) and BCNU, with the potential for broad use against a variety of solid tumors.

Novel feedback inhibition of surface antigen synthesis by mammalian target of rapamycin (mTOR) signal and its implication for hepatitis B virus tumorigenesis and therapy

Ground glass hepatocytes (GGHs) harboring hepatitis B virus (HBV) pre-S mutants have been recognized as precursor lesions of hepatocellular carcinoma (HCC). Previously, we observed the activation of mammalian target of rapamycin (mTOR) in GGHs and HCCs, together with a decreased expression of HBV surface antigen (HBsAg) in HCC tissues. It is, therefore, hypothesized that the activation of mTOR during HBV tumorigenesis may potentially down-regulate HBsAg expression. In this study, we verified an inverse relationship between the expression of HBsAg and phosphorylated mTOR (p-mTOR) in 13 of 20 paired nontumorous liver and HCC tissues. In vitro, wild-type or mutant pre-S proteins could activate mTOR in the HuH-7 cell line. Interestingly, the up-regulated mTOR, in turn, suppressed HBsAg synthesis at the transcriptional level via the transcription factor, Yin Yang 1 (YY1), which bound to nucleotide 2812-2816 of the pre-S1 promoter. This inhibitory effect by the mTOR signal could be abolished by the knockdown of histone deacetylase 1 (HDAC1). Furthermore, YY1 was physically associated with HDAC1 in a manner dependent on mTOR activation. Collectively, pre-S protein-induced mTOR activation may recruit the YY1-HDAC1 complex to feedback suppress transcription from the pre-S1 promoter.

CONCLUSION

The activation of mTOR signal in GGHs may feedback suppress HBsAg synthesis during HBV tumorigenesis and explain the observed decrease or absence of HBsAg in HCC tissues. Therapy using mTOR inhibitors for HCCs may potentially activate HBV replication in patients with chronic HBV infection.

Abstract 1701: Activation of Akt/FoxO axis confers resistance to cisplatin in human nasopharyngeal carcinomas

Nasopharyngeal carcinoma (NPC) is one of the predominant cancers found in Southeastern China and Taiwan. Chemotherapy is one of the major treatment modalities, and the cisplatin-based regimen is the front-line treatment. However, NPC patients failing to cisplatin treatment will have a compromised survival. To explore the resistance spectrum and mechanisms of cisplatin resistance in NPC, two cisplatin-resistant sublines (cis6 and cis15) derived from the parental NPC cell line HONE-1 were obtained. Compared with HONE-1 cells, cis6 and cis15 cells showed upto 18-fold resistance to cisplatin in each, and also possessed a cross-resistance to oxaliplatin and arsenic trioxide. The level of platinum-DNA-adduct and γH2AX were significantly decreased in cis6 and cis15 cells. To unravel the behind details, the systems of DNA repair and cisplatin detoxification were examined and found to be more active in both resistant cells. In terms of the DNA repair proteins, the levels of p-DNA-PK and XRCC1 were increased; in terms of cellular localization of cisplatin, the level of copper transporter ATP7A was upregulated; in terms of Nrf2/antioxidant/detoxifizing enzyme, the resistant cells had a higher Nrf2 activity and an increased intracellular level of GSH, GR, NQO1, AKR1C1 and AKR1C2. Moreover, as compared with HONE-1 cells, our results showed that the resistant cells spared the cisplatin-induced cell death via the suppression of pro-apoptotic proteins and the enhancement of anti-apoptotic proteins. Since the members of ErbB family could be overexpressed in NPC and the ErbB/Akt/FoxO axis could involve in the actions of apoptosis, DNA damage repair and detoxification of reactive oxygen species, the ErB/Akt/FoxO were investigated. Indeed, the phosphorylations of Akt, FoxO1, and FoxO3 were upregulated in cis6 and cis15 cells. Thus, the resistance to cisplatin in cis6 and cis15 cells was partially explained by the Akt/FoxO pathway. Surprisingly, EGFR was downregulated in the resistant cells, whereas ErbB2 was upregulated. The elevations of the negative regulators of EGFR, including c-Cbl, GCF and LRIG1, were observed in cis6 and cis15 cells, indicating that the negative regulation of EGFR could be at the levels of transcription and protein degradation. Since LRIG1 could be upregulated and negatively feedback to control the level of ErbB after the ErbB was activated, it was plausible that the overexpression of ErbB2 upregulated the expression of LRIG1 and subsequently, caused the downregulation of EGFR. Nevertheless, the hypothesis which both overexpression of ErbB2 and LRIG1 contributes to the resistance to cisplatin in our cell model awaits experimental verification. Taken together, our results suggested that the mechanism responsible for cisplatin resistance in NPC, at least in part, through Akt/FoxO pathway. (The study was supported by grants of Department of Health DOH99-TD-C-111-004, Taiwan, R.O.C.)

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1701. doi:10.1158/1538-7445.AM2011-1701

D-501036, a novel selenophene-based triheterocycle derivative, exhibits potent in vitro and in vivo antitumoral activity which involves DNA damage and ataxia telangiectasia-mutated nuclear protein kinase activation

D-501036 [2,5-bis(5-hydroxymethyl-2-selenienyl)-3-hydroxymethyl-N-methylpyrrole] is herein identified as a novel antineoplastic agent with a broad spectrum of antitumoral activity against several human cancer cells and an IC(50) value in the nanomolar range. The IC(50) values for D-501036 in the renal proximal tubule, normal bronchial epithelial, and fibroblast cells were >10 mumol/L. D-501036 exhibited no cross-resistance with vincristine- and paclitaxel-resistant cell lines, whereas a low level of resistance toward the etoposide-resistant KB variant was observed. Cell cycle analysis established that D-501036 treatment resulted in a dose-dependent accumulation in S phase with concomitant loss of both the G(0)-G(1) and G(2)-M phase in both Hep 3B and A-498 cells. Pulsed-field gel electrophoresis showed D-501036-induced, concentration-dependent DNA breaks in both Hep 3B and A-498 cells. These breaks did not involve interference with either topoisomerase-I and topoisomerase-II function or DNA binding. Rapid reactive oxygen species production and formation of Se-DNA adducts were evident following exposure of cells to D-501036, indicating that D-501036-mediated DNA breaks were attributable to the induction of reactive oxygen species and DNA adduct formation. Moreover, D-501036-induced DNA damage activated ataxia telangiectasia-mutated nuclear protein kinase, leading to hyperphosphorylation of Chk1, Chk2, and p53, decreased expression of CDC25A, and up-regulation of p21(WAF1) in both p53-proficient and p53-deficient cells. Collectively, the results indicate that D-501036-induced cell death was associated with DNA damage-mediated induction of ataxia telangiectasia-mutated activation, and p53-dependent and -independent apoptosis pathways. Notably, D-501036 shows potent activity against the growth of xenograft tumors of human renal carcinoma A-498 cells. Thus, D-501036 is a promising anticancer compound that has strong potential for the management of human cancers.

Tamoxifen accelerates proteasomal degradation ofO6-methylguanine DNA methyltransferase in human cancer cells

Tamoxifen, a synthetic triphenyl-ethylene compound, is a member of a class of anticancer drugs known as selective estrogen receptor modulators. It may block tumor growth by mimicking estrogen and binding to the estrogen receptors, preventing cancerous growth. Clinical studies have demonstrated that a combination chemo/hormonal therapy regimen with tamoxifen and O(6)-alkylating drugs increased the tumor response rate in cancer patients. The mechanism of action of this combined regimen remains undefined. In this study, we demonstrated that treatment of human colorectal HT-29 carcinoma cells with tamoxifen decreased the repair activity and expression level of O(6)-methylguanine DNA methyltransferase (MGMT) protein in a concentration- and time-dependent manner. This inhibition was also shown in other malignant human cells, regardless of their estrogen receptor status. Furthermore, MGMT inactivation by tamoxifen was associated with a significantly increased susceptibility of cells to 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). No alteration in MGMT mRNA levels was observed in tamoxifen-treated cells. The half-life of MGMT protein was markedly decreased in the presence of tamoxifen. Tamoxifen-induced MGMT degradation could be blocked by MG-132, a proteasome inhibitor. An increased level of ubiquitinated MGMT protein was found after tamoxifen treatment. We conclude that tamoxifen decreased the MGMT protein level by accelerating protein degradation through the ubiquitin-dependent proteasomal pathway. These findings provide a strong rationale for combined chemo/hormonal therapy with tamoxifen and BCNU in the treatment of human cancers.

Abrogation of skin disease in LUPUS-prone MRL/FASlpr mice by means of a novel tylophorine analog

OBJECTIVE

To test the therapeutic effect of DCB-3503, a synthetic compound derived from a natural product that inhibits NF-kappaB, on end-organ disease in the MRL-Fas(lpr) murine model of systemic lupus erythematosus (SLE).

METHODS

Eight-week-old female MRL/Fas(lpr) mice were treated intraperitoneally with a low (2 mg/kg) or high (6 mg/kg) dose of DCB-3503 for 10 weeks. Control groups were administered vehicle treatment alone (negative control) or 25 mg/kg cyclophosphamide (positive control). Mice were bled before (8 weeks) and during (13 weeks) treatment, and when they were killed (20 weeks), and serum samples were analyzed for total IgM and IgG levels and autoantibody titers. When the mice were killed, spleen and lymph nodes (axillary, brachial, and cervical) were examined by flow cytometric analysis. The presence of skin and renal disease was determined by histopathologic analysis.

RESULTS

DCB-3503 reduced anti-double-stranded DNA and antichromatin autoantibodies and nearly abrogated inflammatory skin disease in MRL/Fas(lpr) mice; however, it had little effect on histologic kidney disease. Treated mice did not have hematologic or hepatic toxicity. These data indicate that end-organ disease in MRL/Fas(lpr) mice responds differentially to NF-kappaB inhibitor.

CONCLUSION

DCB-3503 causes significant abrogation of skin disease in MRL/Fas(lpr) mice and may potentially be beneficial in the treatment of inflammatory skin disease in SLE.

Mitochondria-mediated and p53-associated apoptosis induced in human cancer cells by a novel selenophene derivative, D-501036

D-501036 [2,5-bis(5-hydroxymethyl-2-selenienyl)-3-hydroxymethyl-N-methylpyrrol], a novel selenophene derivative, is a highly potent cytotoxic agent with broad spectrum antitumor activity. The present study was undertaken to explore the mechanism(s) through which D-501036 exerts its action mode on the cancer cell death. D-501036 was found to suppress the growth of KB and HepG(2) cells in an irreversible manner. The results of annexin-V assays and PARP cleavage studies were consistent with the D-501036-induced apoptosis. Findings provided a strong support for the induction of mitochondria-mediated apoptosis by this drug. The examination of two canonical pathways of initiation caspases, those for caspases -8 and -9, revealed that caspase-9 protein and the activities of caspases -9 and -3 were increased in a dose- and time-dependent manner. The concentrations of Fas/Fas-L and procaspase-8 and the activity of caspase-8 were not altered. Furthermore, the mitochondrial membrane potential permeability and the release of cytochrome c to the cytosol were both increased by D-501036. The concentrations of the pro-apoptotic protein Bax and translocation of Bax from the cytosol to the mitochondria were increased in response to D-501036, whereas the concentrations of the anti-apoptotic protein Bcl-2 were decreased. Two DNA damage-related pro-apoptotic proteins, Puma and Noxa, were upregulated in a dose- and time-dependent manner. These pro-apoptotic and anti-apoptotic proteins are downstream effectors of p53. Accordingly, the phosphorylated and total forms of p53 were induced and p53 was translocated from the cytosol to the mitochondria in response to D-501036 treatment. Collectively, we conclude that D-501036 induces cellular apoptosis through the p53-associated mitochondrial pathway.

Inhibition of cell growth and nuclear factor-κB activity in pancreatic cancer cell lines by a tylophorine analogue, DCB-3503

A tylophorine analogue, DCB-3503, has been shown to have potent activity against tumor growth in vitro and in vivo, as well as activity in an autoimmune disease model in vivo. This study focuses on investigating the mechanisms responsible for antitumor activity of DCB-3503. The concentrations for inhibiting 50% growth/colony formation ability are 50/162 and 40/149 nmol/L for PANC-1 and HPAC cells, respectively. The growth inhibition effects are associated with DCB-3503-induced reprogramming of tumor cells. DCB-3503 could interfere with cell cycle progression. Several cell cycle regulatory proteins, including cyclin D(1), are down-regulated by DCB-3503. Using several different transcription elements coupled with a reporter gene, it was found that the nuclear factor-kappaB (NF-kappaB) signaling pathway is the most sensitive pathway mediator affected by DCB-3503. The inhibition of NF-kappaB activity is dependent on the down-regulation of nuclear phosphorylated p65, a component of the active form of the NF-kappaB complex. Such a decrease in nuclear phosphorylated p65 can be reversed by a proteosome inhibitor. Furthermore, the activity and protein expression of nuclear IkappaB kinase alpha, which is responsible for p65 phosphorylation, is suppressed and down-regulated in cells treated with DCB-3503. In summary, DCB-3503 could affect cell cycle regulatory proteins and is a potent modulator of NF-kappaB function. It is a potentially useful compound in the management of cancers in which cyclin D1 overexpression and high NF-kappaB activity play a pivotal role.

Phase I study of biweekly gemcitabine followed by oxaliplatin and simplified 48-h infusion of fluorouracil/leucovorin for advanced pancreatic cancer

OBJECTIVES

To evaluate the feasibility and maximal tolerated dose (MTD) of oxaliplatin of a triplet regimen consisting of gemcitabine, oxaliplatin and infusional fluorouracil (5-FU)/leucovorin (LV) (GOFL) for advanced pancreatic cancer.

PATIENTS AND METHODS

Patients with histologically proven metastatic or unresectable, locally advanced pancreatic adenocarcinoma were eligible to take part in the study. The treatment consisted of fixed-rate infusion (10 mg/m2/minute) of 800 mg/m2 gemcitabine followed by 2-h infusion of oxaliplatin and then 48-h infusion of 5-FU/LV day 1 and day 15 every 4 weeks. The oxaliplatin would be evaluated at three dose levels, 65, 75 and 85 mg/m2.

RESULTS

A total of 15 patients were enrolled at three dose levels. Dose-limiting toxicity of neutropenic fever and grade 4 thrombocytopenia occurred in one of each six patients at oxaliplatin dose level of 65 mg/m2 and 85 mg/m2, respectively. The MTD of oxaliplatin for this combination was 85 mg/m2. After a median four cycles of treatment, grade 3/4 neutropenia occurred in 46.7% of patients and thrombocytopenia in 13.3%. Non-hematological toxicities were generally of grade 1/2. Objective tumor response was observed in five patients (33.3%, 95% confidence interval, 6.3-60.4%).

CONCLUSION

Biweekly GOFL is a feasible regimen for advanced pancreatic cancer. For further phase II studies, the recommended dose of oxaliplatin is 85 mg/m2.

Effects of a novel tylophorine analog on collagen-induced arthritis through inhibition of the innate immune response

OBJECTIVE

To test the effects of a novel tylophorine analog, DCB 3503, on the prevention and treatment of collagen-induced arthritis (CIA) and to elucidate its underlying mechanisms.

METHODS

DBA/1J mice were immunized with type II collagen, and in some cases, lipopolysaccharide (LPS) was used to boost the development of arthritis. DCB 3503 was injected intraperitoneally before or after the onset of CIA. Mice were monitored to assess the effects of DCB 3503 on the clinical severity of the disease, and pathologic changes in the joints were examined histologically. Levels of tumor necrosis factor alpha (TNFalpha) and interleukin-1beta (IL-1beta) in serum and joint tissues were measured by enzyme-linked immunosorbent assay and by cytometric bead array analysis. The effect of DCB 3503 on LPS-induced proinflammatory cytokines from bone marrow-derived dendritic cells was determined by flow cytometry.

RESULTS

DCB 3503 significantly suppressed the development and progression of CIA. Moreover, DCB 3503 completely blocked the LPS-triggered acceleration of joint inflammation and destruction. Consistent with its effects in vivo, DCB 3503 significantly suppressed the synthesis of proinflammatory cytokines in inflamed joints as well as cytokine synthesis by macrophages examined ex vivo. Treatment also reduced the levels of inflammatory cytokines (IL-6, IL-12, TNFalpha, and monocyte chemotactic protein 1) produced by bone marrow-derived dendritic cells in vitro. However, DCB 3503 showed no direct effects on T cell proliferation and B cell antibody response.

CONCLUSION

Because of its ability to specifically suppress innate immune responses, DCB 3503 may be a novel therapeutic agent for inflammatory arthritis in humans.

Phase I and pharmacokinetic study of oral thalidomide in patients with advanced hepatocellular carcinoma

PURPOSE

To evaluate the dose-limiting toxicities (DLT), maximum tolerated dose (MTD), and pharmacokinetics of thalidomide in patients with advanced hepatocellular carcinoma (HCC).

METHODS

Patients with advanced HCC who were not feasible for definitive local therapy were eligible. Patients were enrolled in a cohort of three to receive thalidomide twice daily for 1 week to determine the MTD. Intra-patient dose escalation was permitted. Pharmacokinetic studies were performed at the first dose level and repeated at the second dose level of each patient.

RESULTS

Fifteen patients were accrued at four dose levels with the starting dose range 100-400 mg/day. Two patients at 400 mg/day experienced DLT (grade 3 angioedema and dyspnea, respectively). The MTD of twice-daily schedule was determined as 300 mg/day. The mean steady-state maximal blood concentration and mean steady-state area under the curve had a trend toward positive correlation, but non-linear proportionate, to the daily dose of thalidomide. Pharmacokinetic parameters are comparable for patients of Child-Pugh's A and B. Apparent mild, transient drug-induced transaminitis was early onset, self-limited, which occurred in 30.7% of patients. Serum hepatitis B or C viral titers was largely not affected.

CONCLUSION

The absorption and elimination of thalidomide are not significantly different in HCC patients with compensated or decompensated hepatic dysfunction.

Phase I-II trial of weekly gemcitabine plus high-dose 5-fluorouracil and leucovorin in advanced pancreatic cancer

BACKGROUND

Pancreatic cancer is a dismal disease. Few drugs, including gemcitabine and 5-fluorouracil (5-FU), have notable antitumor effects against advanced pancreatic cancer. The purpose of the present study was to determine the maximum tolerated dose (MTD) of 5-FU and the efficacy and toxicity profile of weekly gemcitabine plus infusional 5-FU/leucovorin in advanced pancreatic cancer.

METHODS

Patients with histo-/cytologically confirmed, advanced pancreatic cancer were eligible. Treatment consisted of a 30-min infusion of gemcitabine (800 mg/m2), followed by a 24-h infusion of 5-FU and leucovorin (300 mg/m2) at day 1, day 8 and day 15 every 28 days, and was termed the GemFL24 regimen. The dose of 5-FU was escalated from 1600, 2000, to 2600 mg/m2 in the phase I study, and fixed MTD for subsequent enrolled patients.

RESULTS

Eighteen patients were enrolled in the phase I study, and 24 in phase II. The MTD of 5-FU was 2000 mg/m2, with major dose-limiting toxicities being febrile neutropenia and delayed recovery from neutropenia. The dose intensity of gemcitabine of the 35 patients with 5-FU dosage set at MTD was 593 mg/m2 per week. In the entire series of 42 patients, myelosuppression was the main toxicity, with grade 3 neutropenia in eight patients, and grade 3/4 thrombocytopenia in six. On an intention-to-treat analysis, the overall and clinical benefit response rates were 22% and 46%, respectively; with median progression-free and overall survival of 4.1 and 6.9 months, respectively.

CONCLUSIONS

The GemFL24 regimen is a feasible and moderately active treatment with manageable toxicities for advanced pancreatic cancer, and could be a basis for further combination with other anticancer drugs.

Prognostic implications of the expression of erbB2, topoisomerase II alpha and thymidylate synthase in metastatic gastric cancer after fluorouracil-based therapy

OBJECTIVE

This retrospective study aimed to ascertain the expression of erbB2 in relation to topoisomerase II alpha (T2 alpha) and thymidylate synthase (TS) markers in 30 consecutive metastatic gastric cancer patients with a specimen available for study.

METHODS

All patients had been entered on consecutive chemotherapeutic clinical trials that were all 5-fluorouracil based. The specimens were evaluated by fluorescence in situ hybridization to ascertain erbB2 and T2 alpha gene amplification, and by immunohistochemical staining for T2 alpha and TS protein expression.

RESULTS

erbB2 amplification was detected in 16.7% of specimens, with co-amplification of the T2 alpha gene in 40%, and 44% had undetectable TS protein expression. Kaplan-Meier survival curves showed significantly prolonged overall survival in patients with erbB2 and T2 alpha gene amplification, T2 alpha protein overexpression and absence of TS protein expression (P = 0.0011, P = 0.0048, P = 0.0061 and P = 0.0267, respectively, by log rank test). There was a positive correlation between erbB2 amplification and T2 alpha amplification, T2 alpha protein overexpression, and a trend towards absence of TS expression (P = 0.0001, P = 0.003 and P = 0.066 by Fisher's exact test).

CONCLUSION

High dose fluorouracil/leucovorin-based chemotherapy may have the potential to reverse the adverse effects resulting from erbB2 gene amplification in gastric cancer.

A phase I study of weekly docetaxel, 24-hour infusion of high-dose fluorouracil/leucovorin and cisplatin in patients with advanced gastric cancer

OBJECTIVES

To determine the maximum-tolerated dose (MTD) and dose-limiting toxicity (DLT) of both docetaxel and 5-fluorouracil (5-FU) when administered weekly in a regimen of docetaxel, 5-FU/leucovorin and cisplatin (DFLP) for 2 consecutive weeks every 3 weeks.

PATIENTS AND METHODS

A total of 31 patients with chemo-naive, advanced adenocarcinoma of the stomach were enrolled in the study. Cisplatin and leucovorin dosages were fixed throughout the study at 30 and 300 mg/m2, respectively. 5-FU dosage was fixed at 1,600 mg/m2 while docetaxel was evaluated at weekly 1-hour infusion dosages of 30, 40 and 50 mg/m2 to determine the MTD. Cisplatin, 5-FU and leucovorin were administered together as a 24-hour continuous infusion following docetaxel. Weekly 5-FU dosages of 1,600, 2,000 and 2,400 mg/m2 were then evaluated after setting the docetaxel dosage at the MTD.

RESULTS

A total of 95 chemotherapy cycles were administered, with a median of three cycles per patient. The MTD of docetaxel was defined at 40 mg/m2. At a docetaxel dosage of 50 mg/m2 per week, the dose-limiting events of grade 4 febrile neutropenia and grade 3 hypomagnesemia occurred. With fixation of docetaxel to 40 mg/m2, the DLT for 5-FU was found at 2,400 mg/m2 per week. This incurred grade 4 neutropenia such that the MTD of 5-FU was defined at 2,000 mg/m2. Grade 3/4 neutropenia occurred in 14 patients (45%), with 2 patients developing febrile neutropenia. Grade 2 and 3 hypomagnesemia and hypokalemia occurred in 9 (41%) and 4 (18%) patients, respectively, of the first 22 patients treated with a 24-hour infusion of cisplatin and 5-FU/leucovorin immediately following docetaxel. Following a change in the cisplatin administration schedule to a 3-hour infusion after 5-FU/leucovorin infusion, no such complications were observed in 9 subsequently treated patients. Grade 2 diarrhea was recorded in 11 patients (35%). Grade 2/3 asthenia occurred in 9 patients (30%), which resolved after correction of electrolyte disorders. Twenty-six patients were assessable for response analysis. There were 2 (7.8%) complete and 14 (53.8%) partial responses, with the overall response rate being 61.5% (95% confidence interval, 41.5-81.6%). Responses were observed at all dose levels.

CONCLUSION

Two consecutive weeks of DFLP infusions every 3 weeks appear to be an active regimen with a tolerable toxicity profile in advanced gastric cancer. For further phase II studies, the recommended dose for this combination is 40 mg/m2 of docetaxel and 2,000 mg/m2 of 5-FU per week.

Pseudomonas exotoxin A-epidermal growth factor (EGF) mutant chimeric protein as an indicator for identifying amino acid residues important in EGF-receptor interaction

Epidermal growth factor (EGF) was fused to the carboxyl end of a modified pseudomonas exotoxin A that has its toxin binding domain deleted. This chimeric toxin designated as PE(delta Ia)-EGF kills A431 cells through the EGF receptor-mediated pathway. In this study, we used a random mutagenesis approach to make point mutations on EGF, followed by replacing the wild type EGF in PE(delta Ia)-EGF with these EGF mutants. We have constructed 14 different PE(delta Ia)-EGFmutants, and examined their EGF receptor binding activity as well as their cytotoxicity to A431 cells. Our results showed that individual mutations of Val19 to Glu and Val34 to Asp in the EGF domain of PE(delta Ia)-EGFmutants resulted in an increase in the binding affinity to EGF receptor and cytotoxicity to A431 cells. On the other hand, individual mutations of His16 to Asp and Gly18 to Ala in the EGF domain of PE(delta Ia)-EGFmutants lead to a decrease in the binding affinity to EGF receptor and cytotoxicity to A431 cells. In addition, mutations of any of the cysteine residues of EGF in PE(delta Ia)-EGFmutants resulted in the loss of their binding activity to EGF receptor and a corresponding loss of their cytotoxicity. This study indicates that the cytotoxicity of PE(delta Ia)-EGFmutant to EGF receptor-bearing cells may be used as an indicator to screen mutations of EGF important in EGF-receptor interactions.

Modulatory effect of crocetin on aflatoxin B1 cytotoxicity and DNA adduct formation in C3H10T1/2 fibroblast cell

Crocetin is a carotenoid isolated from the seeds of Cape jasmine (Gardenia jasminoides). The cytotoxicity and DNA-adduct formation of rat microsome-activated aflatoxin B1 (AFB1) in the C3H10T1/2 cells were significantly inhibited by pretreatment of crocetin. Most significant inhibition was found at the time of 9 h after crocetin pretreatment. Under these experimental conditions, consistent elevation in the cytosolic glutathione (GSH) levels and the activities of GSH S-transferase (GST) and GSH-peroxidase (GSH-Px) were observed. Crocetin treatment also resulted in a decrease in AFB1-DNA adduct formation in vitro, while no effect of crocetin on the formation of AFB1-8,9-oxide in vitro system was detected as measured by the Trisdiol method. From these results, we suggested that the protective effect of crocetin on the AFB1-cytotoxicity in C3H10T1/2 cells might be due to the cellular defense mechanisms that elevated the cytosol GSH and the activities of GST and GSH-Px.

Effect of ethanol on hepatotoxicity and hepatic DNA-binding of aflatoxin B1 in rats

The hepatocarcinogen aflatoxin B1 is converted to reactive metabolites that bind covalently to cellular macromolecules. These metabolites may also react with glutathione, resulting in the formation of glutathione conjugates and detoxication of the reactive metabolite. When rats were pretreated with ethanol by gastric intubation at a dose of 100 mmol/kg, 6 hr (the time of maximal GSH depletion) before the administration of aflatoxin B1, the covalent binding of 8,9-epoxide-aflatoxin B1 to DNA in vivo was increased by 47% and the hepatotoxicity was also potentiated. However, the covalent binding was not increased by pretreatment with ethanol 18 hr (time with approximately normal GSH levels) before administration of the toxin, and no potentiation of hepatotoxicity was observed. Pretreatment with a non-toxic dose of ethanol had no effects on the activity of glutathione S-transferase and glutathione peroxidase. These results suggest that the depletion of GSH and the increased formation of DNA-adduct from the liver constitute an important mechanism for the potentiation of aflatoxin B1-induced hepatotoxicity by ethanol.