Curcumin synergistically potentiates the growth inhibitory and pro-apoptotic effects of celecoxib in pancreatic adenocarcinoma cells

BACKGROUND AND AIM

Adenocarcinoma of the Pancreas is a leading cause of cancer-related mortality, accounting for an estimated 30,000 deaths per year in the United States. Multiple studies have indicated that specific cyclooxygenase-2 (COX-2) inhibitors may serve in the prevention and treatment of a variety of malignancies including pancreatic adenocarcinoma. Recent studies had shown that the long-term use of high concentration of COX-2 inhibitors is not toxic free and may be limited due to serious gastrointestinal and cardiovascular side effects. The chemopreventive efficacy of the phytochemical, curcumin has been demonstrated in several in vitro and animal models. In this study we investigated whether curcumin potentiates the growth inhibition effect of a COX-2 inhibitor (celecoxib, Pfizer, NY, USA) in human pancreatic cancer cells.

METHODS

P-34 (expressing high levels of COX-2), and MIAPaCa (expressing low levels of COX-2) and Panc-1 (no expression of COX-2) evaluated cell lines were exposed to different concentrations of celecoxib (0-40 microM), curcumin (0-20 microM) and their combination. Cell viability was by XTT assay. Apoptosis was assessed by flow cytometry and COX-2 expression was measured by Western blotting analysis.

RESULTS

In P-34 cells, curcumin synergistically potentiated the inhibitory effect of celecoxib on cell growth. The growth inhibition was associated with inhibition of proliferation and induction of apoptosis. Western blot analysis showed that COX-2 expression was down-regulated by the combination therapy.

CONCLUSION

Curcumin synergistically augments the growth inhibition inserted by celecoxib in pancreatic cancer cells expressing COX-2. The synergistic effect was mediated through inhibition of COX-2. This may enable the use of celecoxib at lower and safer concentrations and may pave the way for a more effective treatment in this devastating disease.

Establishment and Characterization of a Pancreatic Carcinoma Cell Line Derived from Malignant Pleural Effusion

BACKGROUND/AIMS

A novel cell line, designated p34, was developed from the malignant pleural effusion of a patient with carcinoma of pancreas. The objective of this work was to characterize this cell line.

METHOD

The in vitro studies included karyotype analysis, immunohistochemistry, XTT cell proliferation assay, analysis of the cell cycle by FACS and cell sensitivity to chemotherapeutic drugs and irradiation. Subcutaneous and intra-spleen inoculations into nude mice were carried out to study the tumorigenicity and the metastatic tendency of this cell line.

RESULTS

The p34 cell line showed typical morphological characteristics of epithelial pancreatic tumor cells. The cells were hyperdiploid with a modal number of 48, and had two markers, deletion in the short arm of chromosome 2 and duplication of the short arm of chromosome 8. The doubling time was 16 h. Subcutaneous inoculation of the cells into nude mice yielded 100% tumorigenicity, and intra-spleen inoculation resulted in extensive intra-abdominal spread. The antiproliferative effect of chemotherapy (gemcitabine, cisplatin, taxol and vinorelbine), chemopreventive agents (celecoxib and curcumin) and radiotherapy showed dose-dependent cytotoxicity.

CONCLUSIONS

This p34 cell line can be used as a new model for studying various aspects of the biology of human pancreatic cancer and potential treatment approaches for the disease.

Correlation of toxicity with pharmacokinetics of pegylated liposomal doxorubicin (Doxil) in metastatic breast carcinoma

BACKGROUND

Doxil (ALZA Corp., Mountain View, CA) is a formulation of doxorubicin in polyethylene-glycol coated liposomes with a prolonged circulation time and unique toxicity profile. As yet, the effect of the dose schedule on toxicity and the correlation of toxicity with pharmacokinetics have not been directly addressed.

METHODS

The objectives of this study were to examine the toxicity profile and pharmacokinetics of various dose schedules of Doxil in a group of patients with metastatic breast carcinoma (MBC) previously treated with chemotherapy. Forty-five patients received a total of 268 courses of Doxil (median per patient, 5; range, 1-19). Six dose schedules were investigated: 35 mg/m2 every 3 weeks (11 patients), 45 mg/m(2) every 3 weeks (5 patients), 50 mg/m(2) every 4 weeks (5 patients), 60 mg/m(2) every 4 weeks (6 patients), 65 mg/m(2) every 5 weeks (6 patients), and 70 mg/m(2) every 6 weeks (12 patients). Doxil pharmacokinetics was examined in 24 of these patients at the dose levels of 35, 45, 60, and 70 mg/m(2).

RESULTS

Stomatitis was dose related, with higher incidence and severity at doses of 60-70 mg/m(2). Skin toxicity in the form of palmar-plantar erythrodysesthesia (PPE) developed usually after two or more courses of treatment and was schedule dependent with shorter dosing intervals leading to increased frequency and severity of skin manifestations. Myelosuppression, mainly as leukopenia/neutropenia, was dose dependent but mild and uncomplicated in most cases. Hair loss was infrequent (< 7%) and always of limited extent. Despite high cumulative doses up to 1500 mg/m(2), cardiac toxicity was observed in only 1 patient who received prior mitoxantrone and mediastinal radiotherapy. Objective responses, improvements, and durable stabilizations were observed in 9, 6, and 14 patients, respectively, indicating significant antitumor activity of Doxil in previously treated MBC patients. Doxil pharmacokinetics was well described by a monoexponential elimination curve with a long T(1/2) (median, 79 hours), a slow clearance (median, 40 mL/hour), and a small volume of distribution (median, 3.9 L). Cmax (peak plasma concentration) and AUC (area under the concentration*time curve) increased linearly with dose with a statistically significant correlation. Correlation analysis of dose and pharmacokinetic parameters with Doxil toxicites revealed that stomatitis grade and leukocyte nadir were correlated strongly with dose and Cmax, and weakly with AUC, whereas PPE grade was correlated significantly with only 1 parameter, T(1/2).

CONCLUSIONS

The toxicity of Doxil is dose and schedule dependent and well correlated with pharmacokinetic parameters. Pharmacokinetic guidance of Doxil dosing may be a useful tool.

Continuous interleukin-2 infusion combined with cyclophosphamide- based combination chemotherapy in the treatment of hemato-oncological malignancies. Results of a phase I-II study

The combination of a cyclophosphamide (CTX)-based chemotherapy regimen and interleukin-2 (IL-2) has been shown to provide synergistic effects against malignancy in animal models. We therefore conducted a phase I-II trial combining CTX-based combination chemotherapy or CTX alone with high-dose IL-2 in patients with advanced and refractory malignant disease. Fifteen patients with hemato-oncological malignancies (malignant lymphoma 8, multiple myeloma 3, solid tumor 2, leukemia 2) were enrolled in the study. Continuous high-dose IL-2 infusion was shown to be safely administered, starting as soon as recovery of white blood cell count. All patients developed rebound lymphocytosis 24-48 h after termination of IL-2 infusion. Although grade IV toxicity was observed in 5 patients (7 episodes), all side effects completely subsided. Triple chemotherapy (CTX, etoposide and Ara-C) seemed rather toxic (in this group of heavily treated patients) while CTX alone was well tolerated. Four out of 13 (31%) evaluable patients had partial response and another patient (7%) had stabilization of disease progression lasting 2-8 months. Our conclusion is that the combination of CTX and continuous infusion of IL-2 is feasible and should be investigated in patients with various malignant neoplasms.

[Evolving role of radiation therapy in nonmalignant disorders]

Various nonmalignant disorders have traditionally been treated with radiation therapy. It has almost completely been discontinued due to reports of secondary malignancy. During the past 15 years there has been an evolving role for radiation therapy in various nonmalignant disorders such as meningioma, A-V malformation, prevention of vascular restenosis and heterotopic bone formation. Appropriate follow-up of such patients for diagnosis of secondary malignancy is recommended. Radiation therapy should be carefully considered in diseases not successfully treated with conventional means.

Should soybean agglutinin purging be performed in breast cancer patients undergoing autologous stem cell transplantation? A retrospective analysis of 48 patients

High-dose chemotherapy (HDC) followed by autologous stem cell transplantation (ASCT) has gained an increasing role in the treatment of high-risk Stage II-III and/or metastatic breast cancer patients. Several investigators reported on a high rate of tumor cells contaminating the bone marrow and peripheral blood stem cell collection. Nevertheless, the clinical implication of reinfusion of tumor cells with the stem cells to the relapse rate is still uncertain. In this retrospective analysis we compare the outcome and the toxicity of 29 patients with high-risk Stage II-III and 19 metastatic breast cancer patients who underwent HDC with ASCT. Thirteen patients underwent transplant with soybean agglutinin (SBA)-purged graft, while 35 consecutive patients received unmanipulated graft. Engraftment was significantly faster for the nonpurged transplant. No differences in disease-free survival, freedom from relapse, or overall survival were noted in both groups during a median follow up time of 14 months. We conclude that tumor cell purging using SBA in breast cancer patients is not warranted. New purging methods are needed to assess the role of tumor cell purging in breast cancer patients.

Mucosal melanoma following autologous stem cell transplantation for non-Hodgkin's lymphoma (NHL)

The incidence of secondary malignancy following autologous stem cell transplantation (ASCT) is increasing. We describe a patient with stage IVB Hodgkin's disease who developed primary amelanotic malignant melanoma of the tongue 18 months following autologous stem cell transplantation. She was treated by partial glossectomy and supra-omohyoid neck dissection followed by cytokine-mediated immunotherapy. Malignant melanoma of the skin is a frequent secondary solid tumor seen in patients undergoing stem cell transplantation. However, mucosal melanoma which is rare by itself (0.2-8%) has never been reported in NHL patients following ASCT. Early diagnosis and initiation of combined local and systemic treatments including immuno-therapy may improve the outcome of this rare but lethal complication.

Direct clinical comparison of ultrasound and radiative electromagnetic hyperthermia applicators in the same tumours

Hyperthermia in conjunction with radiation therapy is a promising method for the treatment of superficially or eccentrically located recurrent or advanced primary malignant tumours. The external hyperthermia applicators most commonly used are radiative electromagnetic (including microwave) or ultrasound devices. Each type of device has its own limitations. The aim was to evaluate the temperature distributions obtained as well as the acute and subacute toxicities in patients that were treated with both radiative radiative electromagnetic and ultrasound applicators to the same tumours. Thirty-nine patients treated to 41 hyperthermia fields for a total of 197 hyperthermia treatments were analysed. Thermal parameter include mean, Tmax, mean Tave, mean Tmin, T50, T90, %T > 43.5 degrees C and %T < 41 degrees C. Acute toxicities including pain in field, referred pain, blister/ulceration, positional discomfort and subacute toxicities (occurring with 24 h of treatment) were determined for each type of hyperthermia applicator. Although there were increased acute toxicities (in-field or referred pain) associated with the ultrasound treatments no significant differences between the two methods of heating were observed in temperature distributions or subacute toxicities. We conclude that there is no generally preferred method of heating superficially or eccentrically located tumours and the type of applicator should be selected on a tumour-size and site-specific basis.

Treatment of early-stage gastric lymphoma

The treatment of early-stage gastric lymphoma is controversial. This retrospective analysis reports on the outcome of 24 patients treated in our institution during the past 25 years. Fourteen patients had stage IEA, one patient had IEB, six patients IIEA1, and three patients had stage IIEA2 non-Hodgkin's lymphoma (NHL). Diffuse large cell intermediate-grade NHL was diagnosed in 17 patients, diffuse small cleaved cell in three patients, and diffuse mixed large and small cell lymphosarcoma, low-grade B-cell lymphoma, and unclassified lymphoma in one patient each. Fourteen patients underwent surgery, 21 had radiation therapy (XRT), and 10 patients received chemotherapy. Surgery + XRT were given to 7 patients, surgery + XRT + chemo and XRT alone were delivered to five patients each, and XRT + chemotherapy were employed in four patients. Surgery alone was the initial treatment in two patients and chemotherapy alone was given to one patient. Following treatment 22/24 achieved a complete response. During a mean follow-up period of 77.6 months (range 1-285), five patients relapsed. At 10 years, the actuarial survival of the 15 patients with stage I disease was 57.4% and for stage II it was 51.9% (Gehan P-value 0.33). Freedom from relapse (FFR) was 60.7% and 58.3%, respectively (P-value 0.56). No significant statistical differences in terms of survival and FFR were noted in patients treated with surgery, chemotherapy, or XRT. The outcome of patients treated with triple-modality therapy was similar to those treated with double-modality therapy and to patients treated with XRT alone. Gender, age, presenting symptoms, depth of tumor through the gastric wall, and stage were not statistically significant for prediction of either survival or FFR. Both surgery + XRT and chemotherapy + XRT are effective in the treatment of early-stage gastric disease. XRT alone is equally effective as two or three modality treatments in the subset of patients with early-stage gastric lymphoma. However, the low number of patients treated with various approaches over a long period precludes a firm conclusion. Until prospective randomized studies are initiated, management programs should be individually tailored.

Radiation Therapy in Epidemic, Aids-Related Kaposi's Sarcoma in Southern Africa

Aims and background

Acquired Immunodeficiency Syndrome (AIDS) associated Kaposi's Sarcoma (EKS) is widely spread in the Southern African Region. No large studies concerning the role of radiation therapy in the Southern African variant of EKS have been reported to date.

Methods

Over a 10 year period (1982-1992) 25 patients with EKS (disseminated skin involvement) were treated primarily with radiation therapy at the Johannesburg General Hospital. Radiation fields were individually tailored to the extent of the disease. Total administered doses ranged between 8-12 Gy (single fraction) to 24-30 Gy fractionated over 2-3 weeks.

Results

Overall response and symptomatic relief rates were 72% and 80%, respectively. Toxicity was mild and manageable.

Conclusions

Our retrospective analysis supports the use of radiation therapy for the Southern African type of EKS.

Thermometry of interstitial hyperthermia given as an adjuvant to brachytherapy for the treatment of carcinoma of the prostate

PURPOSE

Recurrence in the prostatic gland remains a significant problem in the management of locally advanced prostatic cancer. Transperineal thermobrachytherapy has been utilized in an attempt to improve local tumor control. The purpose of this study was to quantitate the temperature distributions obtained in carcinoma of the prostate treated with interstitial radiofrequency-induced hyperthermia given in conjunction with 192Ir brachytherapy in a Phase I study.

METHODS AND MATERIALS

From 1987 until 1992, 36 patients (5 with locally recurrent, 15 with Stage B, and 16 Stage C prostate cancers) were treated with interstitial brachytherapy implants supplemented with radiofrequency-induced hyperthermia. An array of 7-32 stainless steel trocar electrodes (outer diameter = 1.5 mm, interelectrode spacing = 8 mm) were implanted into the prostate gland through a perineal approach utilizing a specially designed template. Each trocar was electrically insulated along the length which traversed surrounding normal tissues. One to three additional plastic catheters were implanted for automated temperature mapping. Thirty-four of these procedures were performed following lymph node sampling. However, the last two removable interstitial hyperthermic prostate implants were done by the transperineal route under ultrasound guidance. A hyperthermia treatment (goal of 43 degrees C for 45 minutes) was given immediately prior to the insertion and immediately following the removal of the 192Ir. A computer-controlled radiofrequency-based generator (freq. 0.5 MHz) implementing electrode multiplexing was used to induce and maintain elevated temperatures.

RESULTS

Transient local pain was the most common treatment limiting factor. The average values of the measured minimum, mean, and maximum temperatures were 38.9 degrees C, 41.9 degrees C, and 45.7 degrees C in tumor, and 37.7 degrees C, 39.8 degrees C, and 42.9 degrees C in surrounding normal tissue, respectively. The percentages of mapped temperatures exceeding 41 degrees C, 42 degrees C, and 43 degrees C were 67%, 46%, and 27% in tumor, and 26%, 11%, and 4% in normal surrounding tissue, respectively.

CONCLUSION

From this study we conclude that heterogeneous temperature distributions were induced in the prostate; significant normal tissue protection was realized in part through the selective insulation of sections of each electrode; and interstitial radiofrequency-induced hyperthermia of the prostate is feasible and well tolerated, with further technical developments warranted.

Prognostic factors in metastatic malignant melanoma treated with combined radiation therapy and hyperthermia

From May 1981 to September 1991, 38 patients with metastatic malignant melanoma were treated with combined radiation therapy and hyperthermia to a total of 97 hyperthermia treatment fields. Prior treatments to these sites included surgery (31 patients, 76 fields), chemotherapy (18 patients, 54 fields), immunotherapy (14 patients, 42 fields) and radiation therapy (7 patients, 13 hyperthermia fields). Hyperthermia was given to fields located in the head and neck region, trunk and extremities in 30, 45 and 22 cases, respectively. Nodular-diffuse tumours were present in 86 fields while 11 fields were treated for microscopic residual tumour deposits. Concurrent radiation therapy was given in 180-400 cGy per fraction, 2-5 times per week for a mean total dose of 4098 cGy per field. Hyperthermia treatments were delivered using either microwave or ultrasound devices (286 and 48 treatments, respectively) with a mean (range) of 3.4 (1-14) hyperthermia treatments per field for a mean (range) of 43 (10-70) min per field. Patients (n = 34; 84 fields) were available for follow-up for a mean (range) of 14.6 (0.4-82.5) months. At 3 weeks post-treatment, 34 fields had complete, ongoing, or partial responses; 39 fields had no response; and there were no recurrences in the 11 fields treated for microscopic residual disease. Local control was maintained in 31% (26/84) fields with a mean follow-up of 14.6 months. At 36 months, five patients remained alive with complete control of their treated local disease. Statistical analyses revealed that patients with soft tissue metastases only, who were older at the time of hyperthermia, had a longer time between initial diagnosis and hyperthermia treatment, received a higher dose of radiation, had no previous chemotherapy, and had small tumour volumes, had a higher initial response. Multivariate analyses revealed that the three-covariate model including time interval between initial diagnosis and hyperthermia treatment, previous chemotherapy, and metastases to soft tissue only, best predicted response. The results of the investigation support the continued study of combined radiation therapy and hyperthermia treatments for selected patients with metastatic melanoma, and indicate that long-term survival can occasionally be obtained with this approach.

Stanford 3D hyperthermia treatment planning system. Technical review and clinical summary

In the field of deep regional hyperthermia cancer therapy the Sigma 60 applicator of the BSD-2000 Hyperthermia System is one of the most widely used devices. This device employs four independent sources of radiofrequency electromagnetic energy to heat tumour sites deep within the body. The difficulty in determining the input parameters for the four sources has motivated the development of a computer-based three-dimensional (3D) treatment planning system. The Stanford 3D Hyperthermia Treatment Planning System has been in clinical use at Stanford Medical Center for the past 2 years. It utilizes a patient-specific, three-dimensional computer simulation to determine safe and effective power deposition plans. An optimization programme for the selection of the amplitudes, phases and frequency for the sources has been developed and used in the clinic. Examples of the application of the treatment planning for hyperthermia treatment of pulmonary, pelvic, and mediastinal tumours are presented. Methods for quantifying the relative effectiveness of various treatment plans are reviewed.

Persistent and/or late complications of combined radiation therapy and hyperthermia

Persistent and/or late complications were analysed in 64 patients (183 fields) that were treated with combined hyperthermia and radiation therapy for advanced, recurrent or metastatic cancer. The incidence and type of complications were evaluated over a minimum follow-up period of 2 years from the onset of treatment (mean 38.7 months; range 24-82.5 months). The primary malignancies included: breast (39), melanomas (6), adenoid cystic carcinomas of salivary glands (4), prostate (4), soft tissue sarcomas (3), squamous cell carcinoma of head and neck (3), lymphomas (3), transitional cell carcinoma of bladder (1) and basal cell carcinoma of the skin (1). The persistent complications noted included induration and fibrosis (39 hyperthermia fields, 22 patients), ulceration at the site of prior tumour (three patients, three fields), and ulceration in normal tissue (one patient, one field). Brachial plexopathy developed in one patient treated for recurrent breast cancer, but she had active disease at that time. A squamous cell carcinoma of the skin developed within the treatment field in a breast cancer patient. Radionecrosis of the mandible was seen in one patient treated for a floor of the mouth cancer, and osteomyelitis with septic arthritis developed in one patient treated for a soft tissue sarcoma of the thigh. Univariate logistic regression analyses of pretreatment and radiation-hyperthermia treatment parameters revealed that maximal tumour temperature had a borderline significant correlation with the development of complications (p = 0.07). Multivariate analyses of the pretreatment and treatment parameters revealed the best-two-covariate model to predict complications included mean maximal tumour temperature and tumour type (macroscopic tumours had greater incidence of complications than for microscopic residual disease). The rate and type of persistent and/or late complications seen following combined radiation and hyperthermia did not appear to dramatically differ from those that would be anticipated from irradiation alone in this patient population, with the exception of an increased incidence of areas of induration and tumour necrosis.

Cancer metastatic to the penis: treatment with hyperthermia and radiation therapy and review of the literature

Metastatic cancer to the penis is rare, its optimum treatment remains poorly defined and the outcome of patients with such metastases is poor. Hyperthermia in conjunction with radiation therapy has been shown to be an effective modality in the treatment of locally advanced or recurrent cancer and hyperthermia alone is under evaluation in treating benign disorders, such as hypertrophy of the prostate. Recently, 4 patients with symptomatic metastatic lesions to the penis (3 had primary prostatic cancer and 1 had rectal cancer) were treated with radiation therapy and hyperthermia. Treatment was well tolerated except for pain during hyperthermia, which limited the temperatures that could be obtained. All of the patients improved symptomatically, 1 achieved a complete response and 2 had partial responses. No significant complications were noted. Symptomatic control was maintained in all patients for the duration of their survival. This limited series suggests the possible role of local hyperthermia as an adjunct to radiation therapy in the treatment of metastases to the penis.

Peripheral neuropathy and myonecrosis following hyperthermia and radiation therapy for recurrent prostatic cancer: correlation of damage with predicted SAR pattern

During the past 10 years, numerous phase I-II studies were conducted and provided clinical experience with combined radiation therapy and hyperthermia treatments. Among the rare complications reported in these combined radiation therapy-hyperthermia trials were myonecrosis and peripheral neuropathy which were felt, mainly on a clinical basis, to be caused by local heat damage. Recently, such complications were noted in two patients with recurrent prostatic cancer treated in our department with radiation therapy combined with deep regional hyperthermia delivered by the Sigma-60 applicator of the BSD 2000 hyperthermia system (Salt Lake City, UT, USA). Analysis of the results of three-dimensional modelling of the SAR (specific absorption rate, W/kg) pattern in these patients indicated high SAR at the sites of the complications. Pretreatment three-dimensional modelling or other methods of predicting potential areas of high power deposition may have a role for future hyperthermia treatment planning aiding in the prevention of possible local heat damage and providing improved delivery of heat to the target volume.