Orthomolecular Oncology Review: Ascorbic Acid and Cancer 25 Years Later

The effect of ascorbic acid on cancer has been a subject of great controversy. This is a follow-up review of the 1979 article by Cameron, Pauling, and Leibovitz published in Cancer Research. In this updated version, the authors address general aspects of ascorbic acid and cancer that have been presented before, while reviewing, analyzing, and updating new existing literature on the subject. In addition, they present and discuss their own mechanistic hypothesis on the effect of ascorbic acid on the cancer cell. The objective of this review is to provide an updated scientific basis for the use of ascorbic acid, especially intravenously as adjuvant treatment in pharmacological nutritional oncology.

Biobanking of Exosomes in the Era of Precision Medicine: Are We There Yet?

The emerge of personalized medicine demands high-quality human biospecimens with appropriate clinical annotation, especially in complex diseases such as cancer, neurodegenerative, cardiovascular, and metabolic alterations in which specimen heterogeneity and individual responses often complicate the development of precision therapeutic programs. In the growing field of extracellular vesicles (EVs) research, exosomes (EXOs)—a particular type of EVs—have been proposed as an advantageous diagnostic tool, as effective delivery vehicles and as therapeutic targets. However, the lack of consensus on isolation methods and rigorous criteria to characterize them puts the term EXO into question at the time that might explain some of the controversial results found in the literature. A lack of response in the biobank network to warrant standard optimized procedures for the isolation, characterization, and storage of EXOs will undoubtedly lead to a waste of resources and failure. This review is aimed at highlighting the increasing importance of EXOs for the clinic, especially in the cancer field, and at summarizing the initiatives taken to improve current isolation procedures, classification criteria, and storage conditions of EXOs as an effort to identify technological demands that biobank platforms face for the incorporation of EXOs and other extracellular vesicle fractions as valuable biospecimens for research.

Erythropoietin Stimulates Tumor Growth via EphB4

While recombinant human erythropoietin (rhEpo) has been widely used to treat anemia in cancer patients, concerns about its adverse effects on patient survival have emerged. A lack of correlation between expression of the canonical EpoR and rhEpo's effects on cancer cells prompted us to consider the existence of an alternative Epo receptor. Here, we identified EphB4 as an Epo receptor that triggers downstream signaling via STAT3 and promotes rhEpo-induced tumor growth and progression. In human ovarian and breast cancer samples, expression of EphB4 rather than the canonical EpoR correlated with decreased disease-specific survival in rhEpo-treated patients. These results identify EphB4 as a critical mediator of erythropoietin-induced tumor progression and further provide clinically significant dimension to the biology of erythropoietin.

Biological significance of HORMA domain containing protein 1 (HORMAD1) in epithelial ovarian carcinoma

The present study was undertaken to determine the expression and biological significance of HORMAD1 in human epithelial ovarian carcinoma. We found that a substantial proportion of human epithelial ovarian cancers expressed HORMAD1. In vitro, HORMAD1 siRNA enhanced docetaxel induced apoptosis and substantially reduced the invasive and migratory potential of ovarian cancer cells (2774). In vivo, HORMAD1 siRNA-DOPC treatment resulted in reduced tumor weight, which was further enhanced in combination with cisplatin. HORMAD1 gene silencing resulted in significantly reduced VEGF protein levels and microvessel density compared to controls. Our data suggest that HORMAD1 may be an important therapeutic target.

Abstract LB-325: Characterization of triple negative breast cancer patients among Hispanics in Puerto Rico

Introduction: Hormone receptor status had been correlated with prognosis in breast cancer patients. Breast cancer patients with no expression of estrogen receptor (ER), progesterone receptor (PR) and her-2 neu (her-2) have been grouped in the Triple Negative Breast Cancer (TNBC) category. At present, these patients have very limited adjuvant therapy alternatives. TNBC has been correlated with poor prognosis among African-American and Hispanic populations. However, there is very few data regarding the prevalence and characterization of TNBC among Hispanics groups (e.g. Puerto Ricans, Cubans, etc.). The objective of this study is to characterize the TNBC population among the Puerto Rican population and to assess whether expression of ER changes the characteristics of the disease in this group. We hypothesize that expression of ER+ in her-2 negative breast cancer tumors will change the initial presentation of the disease. Methods: This cross-sectional study analyzed data from female patients with breast cancer diagnosed between 2000 and 2005, at the I. Gonzalez Martinez Hospital and the Auxilio Mutuo Hospital (n=1,082) in San Juan, Puerto Rico. Information on Her-2 status and other clinical characteristics were retrieved from the hospital's cancer registries and from medical record review. This study was approved by the Institutional Review Boards of the participating hospitals. Logistic regression models were used to evaluate the associations between relevant clinical characteristics and TNBC. We also evaluated whether there were any interaction between age, tumor size and receptor status. Results: The prevalence of TNBC in our study was 16.3% and 58.7% for the Her-2-ER+s phenotype. Patients in the TNBC group have a younger age (<50 yr.) at diagnosis (24.3% vs 75.7%), larger tumor size (>2cm) (70.3% vs 45.6%), invasive ductal histology (87.3% vs 68.7%), and higher tumor grades (III-IV) (49.7% vs 13.2%) compared to Her-2-ERs+. Using multinomial models, we found that, compared to TNBC, women with Her-2-ER+PR- and those with Her-2-ER+PR+ were 1.99 (CI95%=1.15,3.44) and 1.66 (CI95%= 1.11, 2.46) times more likely to have > 50 years at diagnosis as compared to those with <50 years. This relationship is not seen in women with Her-2-ER-PR+ tumors. Furthermore, compared to TNBC, women with Her-2-ER+PR- are 0.4 (IC95%=0.24-0.67) times more likely to have tumors > 2cm. There was no interaction between receptor status, age and tumor size (p=0.582). Conclusions: TNBC in Hispanics from Puerto Rican origin showed the same prevalence of Hispanic women in California. Furthermore, disease characteristics (early age at diagnosis, tumor size, histology and tumor grade) were also similar, suggesting that race has a significant effect in the presentation of TNBC in Hispanic women. In addition, the expression of ER, but not PR in Her-2 negative patients dramatically changes the initial presentation of the disease.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr LB-325. doi:1538-7445.AM2012-LB-325

Chitosan hydrogel for localized gene silencing

OBJECTIVE

To achieve effective delivery of siRNA into target cells in vivo, we have developed a novel approach of siRNA delivery by using local drug delivery systems.

RESULTS

The chitosan hydrogel (CH-HG) displayed a liquid-solid phase transition in a temperature-dependent manner and formed an endothermic hydrogel in tumor tissue after intra-tumoral injection. Additionally, we tested the extent of in vivo delivery following a single intra-tumoral injection of Alexa555 siRNA/CH-HG into A375SM-bearing mice. The Alexa555 siRNA demonstrated higher localization into tumor cells compared to control. The Alexa555 siRNA delivery extends to tumor cells outside of CH-HG and some tumor cells also infiltrated into CH-HG. For therapeutic proof-of-concept studies, CH-HG including TG2-targeted siRNA significantly inhibited tumor growth in melanoma (A375SM) and breast (MDA-MB231) tumor models compared to control (A375SM: 72% reduction and MDA-MB231: 92% reduction, p < 0.001).

EXPERIMENTAL DESIGN

we prepared a CH-HG system loaded with siRNA to enhance localized therapeutic efficacy without risk for systemic side effects. Delivery of siRNA into CH-HG was confirmed by fluorescence microscopy. Antitumor efficacy was examined in mouse models of melanoma (A375SM) and breast (MDA-MD231) cancer.

CONCLUSIONS

This study developed a novel local delivery method for siRNA therapy using the CH-HG system. This approach could have broad applications for multiple localized diseases.

Abstract 1618: Erythropoietin meets a new receptor

Introduction: Recent clinical trials suggest that use of erythropoietin to treat chemotherapy-induced anemia results in enhanced tumor progression and impaired survival in certain cancer patients. Rationalizing these observations with Epo's pleiotropic functionality and the lack of compelling evidence for Epo receptor (EpoR) involvement, we hypothesized the existence of a novel Epo receptor. Capturing this premise in terms of a holistic in silico strategy, we analyzed the secreted human proteome for receptors possessing structural, regulatory and functional features consistent with Epo binding and subsequent tumorigenic signaling. Our results provided EphB4 as the most likely candidate molecule.

Methods: To determine the possible association between EphB4 and Epo-mediated tumor growth, we examined several ovarian (A2780, HeyA8-MDR, SKOV3ip1) and breast (MDA-231) cancer cell lines. In addition, we selected A2780 ovarian cancer cells to develop stable clones in which either EpoR or EphB4 was silenced using shRNA (A2780 shEpoR, A2780 shEphB4). Competitive and kinetic binding studies were performed using 125I- Epo. Proliferation, migration, and invasion assays were performed as described previously. To assess the role of EpoR and EphB4 in Epo-induced tumor growth, we silenced EpoR and/or EphB4 with specific siRNAs loaded into DOPC nanoliposomes. Statistical significance was established at p&lt; 0.05.

Results: Binding studies with 125I- Epo revealed Epo binding to EphB4 in a low-affinity fashion. Exposure of shEpoR cells to soluble EpoR showed non-competitive inhibition; however, exposure to soluble EphB4 competitively inhibited 125I- Epo binding. These results demonstrate the specificity of Epo binding to the EphB4 receptor. At pharmacologically relevant doses, Epo treatment of shEpoR cells led to activation of the Stat-3 pathway. In addition, in vitro functional assays revealed significant effects of Epo on proliferation (p=0.003), migration (p=0.006), and invasion (p=0.02) of shEpoR cells, but not shEphB4 cells. In orthotopic ovarian (Hey-A8 MDR, SKOV3ip1, A2780) and breast (MDA-231) cancer models, treatment with Epo resulted in increased tumor growth compared to untreated animals (1.1 vs. 1.6 g, p=0.05; 0.7 vs. 1.75 g, p=0.03; 0.6 vs. 1.5 g, p=0.02; .012 vs 0.4 g, p=0.006), respectively. In vivo, (A2780 and MDA-231 models), EpoR siRNA did not affect Epo-stimulated tumor growth. In contrast, EphB4 siRNA-DOPC completely blocked Epo-stimulated tumor growth.

Conclusions: Collectively, these results point to EphB4 as an alternative Epo receptor that mediates Epo-induced tumor growth by activating Stat-3. These findings offer exciting theranostic avenues for management of anemic cancer patients.

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 1618. doi:10.1158/1538-7445.AM2011-1618

Targeted delivery of small interfering RNA using reconstituted high-density lipoprotein nanoparticles

RNA interference holds tremendous potential as a therapeutic approach, especially in the treatment of malignant tumors. However, efficient and biocompatible delivery methods are needed for systemic delivery of small interfering RNA (siRNA). To maintain a high level of growth, tumor cells scavenge high-density lipoprotein (HDL) particles by overexpressing its receptor: scavenger receptor type B1 (SR-B1). In this study, we exploited this cellular characteristic to achieve efficient siRNA delivery and established a novel formulation of siRNA by incorporating it into reconstituted HDL (rHDL) nanoparticles. Here, we demonstrate that rHDL nanoparticles facilitate highly efficient systemic delivery of siRNA in vivo, mediated by the SR-B1. Moreover, in therapeutic proof-of-concept studies, these nanoparticles were effective in silencing the expression of two proteins that are key to cancer growth and metastasis (signal transducer and activator of transcription 3 and focal adhesion kinase) in orthotopic mouse models of ovarian and colorectal cancer. These data indicate that an rHDL nanoparticle is a novel and highly efficient siRNA carrier, and therefore, this novel technology could serve as the foundation for new cancer therapeutic approaches.

Targeted gene silencing using RGD-labeled chitosan nanoparticles

PURPOSE

This study aimed to develop an Arg-Gly-Asp (RGD) peptide-labeled chitosan nanoparticle (RGD-CH-NP) as a novel tumor targeted delivery system for short interfering RNA (siRNA).

EXPERIMENTAL DESIGN

RGD peptide conjugated with chitosan by thiolation reaction was confirmed by proton-NMR (H-NMR). Binding of RGD-CH-NP with alphanubeta3 integrin was examined by flow cytometry and fluorescence microscopy. Antitumor efficacy was examined in orthotopic mouse models of ovarian carcinoma.

RESULTS

We show that RGD-CH-NP loaded with siRNA significantly increased selective intratumoral delivery in orthotopic animal models of ovarian cancer. In addition, we show targeted silencing of multiple growth-promoting genes (POSTN, FAK, and PLXDC1) along with therapeutic efficacy in the SKOV3ip1, HeyA8, and A2780 models using siRNA incorporated into RGD-CH-NP (siRNA/RGD-CH-NP). Furthermore, we show in vivo tumor vascular targeting using RGD-CH-NP by delivering PLXDC1-targeted siRNA into the alphanubeta3 integrin-positive tumor endothelial cells in the A2780 tumor-bearing mice. This approach resulted in significant inhibition of tumor growth compared with controls.

CONCLUSIONS

This study shows that RGD-CH-NP is a novel and highly selective delivery system for siRNA with the potential for broad applications in human disease.

Abstract 1811: Breaking scaffolds: Targeting paxillin in ovarian cancer

Background

Paxillin is a mediator of many cellular processes important for cancer progression. Here, we characterize the clinical and biologic significance of paxillin in epithelial ovarian cancer.

Methods

Paxillin and phospho-paxillin expression was determined in 93 human epithelial ovarian cancer specimens. Clinical data were extracted and associations tested using univariate and multivariate analyses. The effect of paxillin silencing on ovarian cancer cell migration and invasion was evaluated in vitro. In vivo paxillin silencing was achieved with siRNA incorporated into DOPC nanoliposomes and its effect on tumor growth, angiogenesis, and proliferation were examined.

Results

Examination of 93 epithelial ovarian cancers revealed moderate to high paxillin expression in 84% and high phospho-paxillin expression in 63% of tumors. High paxillin expression correlated with high tumor grade (p=0.02) and advanced stage (p=0.03). Phospho-paxillin expression was associated with high tumor grade (p=0.01), suboptimal cytoreduction (p=0.01), and decreased overall survival (p&lt;0.001). Compared to non-transformed ovarian epithelial cells (HIO-180), paxillin expression was increased in chemosensitive (HeyA8, SKOV3) and chemoresistant (HeyA8-MDR, SKOV3-TR) ovarian cancer cell lines. Paxillin siRNA resulted in &gt;85% reduction in protein expression in these cell lines. In vitro paxillin silencing decreased HeyA8 and HeyA8-MDR cell migration (60% and 75%) and invasion (55% and 47%). In orthotopic mouse models, paxillin siRNA treatment reduced tumor growth in HeyA8 and HeyA8-MDR by 49% and 31%, respectively, compared to non-targeting siRNA controls. The greatest efficacy was observed by combining paxillin siRNA with docetaxel, resulting in a &gt;90% and 45% reduction in tumor burden over non-targeting siRNA in HeyA8 and HeyA8-MDR tumors, respectively. The dramatic in vivo effects of paxillin silencing are due, in part, to its activation of multiple signaling cascades once localized to the focal adhesion complex. Protein complex immunoprecipitation confirms interactions with Src, FAK, and EphA2 tyrosine kinases as well as effector molecules such as Crk. Paxillin silencing resulted in decreased proliferation by 57%, decreased microvessel density by 72%, and increased apoptosis by 140% in HeyA8 tumors.

Conclusion

Paxillin is overexpressed in epithelial ovarian cancer. Paxillin influences several pathways important to cancer progression and represents a novel and attractive treatment target in ovarian cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1811.

Abstract LB-393: Characterization of triple-negative breast cancer patients among Hispanics in Puerto Rico

Introduction: Hormone receptor status had been correlated with prognosis in breast cancer patients. Breast cancer patients with no expression of estrogen receptor (ER), progesterone receptor (PR) and her-2 neu (her-2) have been grouped in the Triple Negative Breast Cancer (TNBC) category. At present, these patients have very limited adjuvant therapy alternatives. TNBC has been correlated with poor prognosis among African-American and Hispanic populations. However, there is very few data regarding the prevalence and characterization of TNBC among Hispanics groups (e.g. Puerto Ricans, Cubans, etc.). The objective of this study is to characterize the TNBC population among the Puerto Rican population and to assess whether expression of ER change the characteristics of the disease in this group. We hypothesize that expression of ER+ in her-2 negative breast cancer tumors will change the initial presentation of the disease.

Methods: This cross-sectional study analyzed data from female patients with breast cancer diagnosed between 2000 and 2005, at the I. Gonzalez Martinez Hospital and the Auxilio Mutuo Hospital (n=1,082) in San Juan, Puerto Rico. Information on Her-2 status and other clinical characteristics was retrieved from the hospital's cancer registries and from medical record review. This study was approved by the Institutional Review Boards of the participating hospitals. Logistic regression models were used to evaluate the associations between relevant clinical characteristics and TNBC. We also evaluated whether there were any interaction between age, tumor size and receptor status.

Results: The prevalence of TNBC in our study was 16.3% and 58.7% for the Her-2-ER+s phenotype. Patients in the TNBC group have younger age (&lt;50 yr.) at diagnosis (24.3% vs 75.7%), bigger tumor size (&gt;2cm) (70.3% vs 45.6%), invasive ductal histology (87.3% vs 68.7%), and higher tumor grades (III-IV) (49.7% vs 13.2%) compared to Her-2-ERs+. Using multinomial models, we found that, compared to TNBC, women with Her-2-ER+PR- and those with Her-2-ER+PR+ were 1.99 (CI95%= 1.15,3.44) and 1.66 (CI95%= 1.11, 2.46) times more likely to have &gt; 50 years at diagnosis as compared to those with &lt;50 years. This relationship is not seen in women with Her-2-ER-PR+ tumors. Furthermore, compared to TNBC, women with Her-2-ER+PR-are 0.4 (IC95%=0.24-0.67) times more likely to have tumors &gt; 2cm. There was no interaction between receptor status, age and tumor size (p=0.582).

Conclusions: TNBC in Hispanics from Puerto Rican origin showed the same prevalence of Hispanic women in California. Furthermore, disease characteristics (early age at diagnosis, tumor size, and histology and tumor grade) were also similar, suggesting that race has a significant effect in the presentation of TNBC in Hispanic women. In addition, the expression of ER, but not PR in Her-2 negative patients dramatically changes the initial presentation of the disease.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-393.

Abstract 3436: Mechanisms of paraneoplastic thrombocytosis in ovarian carcinoma

Objective: The observation that thrombocytosis (platelet count &gt;450,000/μL) occurs in patients with solid malignancies was made over 100 years ago. However, the underlying mechanisms and clinical implications of paraneoplastic thrombocytosis in epithelial malignancies such as ovarian carcinoma are poorly understood and are the focus of the current study.

Methods: Following IRB approval, clinical parameters and initial complete blood counts (CBC) were evaluated in 608 epithelial ovarian cancer patients. Plasma levels of key megakaryopoietic factors thrombopoietin, IL-1α, IL-3, IL-4, IL-6, IL-11, G-CSF, GM-CSF, stem cell factor, and FLT-3 ligand were assayed in a subset of 150 patients at the time of initial diagnosis with advanced stage, high grade epithelial ovarian cancer using a Luminex immunobead-based cytokine profiling platform. For animal studies, CBCs were measured in control mice as well as syngeneic (2 cell lines) and orthotopic (3 cell lines) mouse models of ovarian cancer. Megakaryocytes in spleen and bone marrow were quantified by bright-field microscopy.

Results: Human study: Thirty-two percent of patients had thrombocytosis at initial diagnosis. Compared to patients with normal platelet counts, women presenting with thrombocytosis were significantly more likely to have advanced stage disease (p=0.013) and poor mean progression-free (1.29 vs 2.73 years, p&lt;0.001) and overall survival (3.01 vs 6.05 years, p&lt;0.001). On multivariate analysis, thrombocytosis remained an independent predictor of decreased overall survival. Plasma levels of megakaryopoietic factors IL-6 and G-CSF significantly correlated with platelet counts (r=0.33, p&lt;0.01 and r=0.18, p=0.03). Animal study: Paraneoplastic thrombocytosis was recapitulated in both syngeneic and orthotopic mouse models of ovarian cancer. Platelet counts were increased by 27-200% in mice bearing invasive ovarian tumors compared to controls (p&lt;0.01) and platelet counts significantly correlated with tumor burden (r=0.61, p&lt;0.05). Thrombocytosis was accompanied by a non-significant increase in leukocytes and decrease in red blood cells. Mean platelet count in the peripheral blood strongly correlated with mean megakaryocyte counts in spleen and bone marrow (r=0.95, p&lt;0.05).

Conclusions: Our data provide additional insight into the clinical significance and etiology of paraneoplastic thrombocytosis in ovarian cancer patients. In vivo studies evaluating the effect of silencing tumor cell production of IL-6 and G-CSF on paraneoplastic thrombocytosis using human-specific siRNA sequences are ongoing. Paraneoplastic thrombocytosis and the interaction between platelets and cancer cells could be targets for developing novel therapeutic strategies.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3436.

Influence of oxygen, albumin and pH on copper dissolution in a simulated uterine fluid

OBJECTIVES

The aim of this paper is to study the influence of albumin content, from 5 to 45 g/L, on copper dissolution and compounds composition in a simulated uterine solution.

METHODS

Experiments were performed in atmospheric pressure conditions and with an additional oxygen pressure of 0.2 atmospheres, at 6.3 and 8.0 pH values, and at a temperature of 37 +/- 0.1 degrees C for 1, 3, 7, and 30 days experimentation time.

RESULTS

The copper dissolution rate has been determined using absorbance measurements, finding the highest value for pH 8.0, 35 g/L albumin, and with an additional oxygen pressure of 0.2 atmospheres: 674 microg/day for 1 day, and 301 microg/day for 30 days. X-ray photoelectron spectroscopy (XPS) results show copper(II) as the main copper oxidation state at pH 8.0; and copper(I) and metallic copper at pH 6.3.

CONCLUSIONS

The presence of albumin up to 35 g/L, accelerates copper dissolution. For high albumin content a stabilisation on the copper dissolution takes place. Corrosion product layer morphology is poorly protective, showing paths through which copper ions can release.

Intravenous vitamin C as a chemotherapy agent: a report on clinical cases

A series of seven cases are presented in which intravenous vitamin C has been used as antineoplastic agent in the treatment of different types of cancers. The cancers cases reviewed are the following: Renal cell carcinoma (2), Colorectal cancer (1), Pancreatic cancer (1), Non-Hodgkin's lymphoma (2) and breast cancer (1). Toxic reactions were not observed at these high doses of intravenous Vitamin C. All patients were prescreened for Glucose 6--phosphate dehydrogenase deficiency before administering intravenous Vitamin C in order to prevent hemolysis.

Intravenous ascorbic acid: protocol for its application and use

High dose intravenous(i.v.) ascorbic acid (AA) has been used as therapy for infectious disease from bacterial and viral origin and adjuvant therapy for cancer. In this publication we describe a clinical protocol that has been developed over the past twenty years utilizing high dose i.v. AA as therapy for cancer. This includes principles of treatment, rationale, baseline workup, infusion protocol, precautions and side effects.

Inhibition of human breast carcinoma cell proliferation by ascorbate and copper

We tested the effect of different concentrations of ascorbic acid (AA), 50, 100, 250 mg/500 mg/dL) with copper sulfate (CS), 10 mg/dL) on human breast carcinoma (MDA-MB231) cell proliferation in vitro. Cell proliferation was measured using a colori-metric assay (Cell proliferation kit II (XTT), Boehringer, NJ). The results of the mean absorbance of the tissue culture at different AA concentrations and a constant CS concentration were as follow: 0.82 +/- 0.03 (control, mean +/- SE), 0.64 +/- 0.02 (CS above); 0.48 +/- 0.03 (50 mg/dL) AA), 0.21 +/- 0.02 (100 mg/dL), 0.08 +/- 0.01 (250 mg/dL) AA, 0.60 +/- 0.05 (500 mg/dL). These results show that a combination of AA and CS inhibits human breast carcinoma cell proliferation in vitro. This cell proliferation inhibitory effect is directly proportional to the AA concentration with the exception of the 500 mg/dL AA dose. This chemotherapeutic effect was optimally enhanced when AA was added at a concentration of 250 mg/dL. The AA concentrations of 500 mg/dL had a biphasic effect on tumor cell proliferation probably due to back and forth redox reactions between AA and dehydroascorbic acid in a closed system. This study provides preliminary evidence that AA and SC can be used as biological response modifiers (BRM) for tumor growth inhibition.

Orthomolecular oncology: a mechanistic view of intravenous ascorbate's chemotherapeutic activity

The effect of vitamin C in cancer has been a subject of great controversy; mainly because of the inconsistent results obtained by oral intakes of ascorbate when used as an anticancer agent. We believe the intravenous application of ascorbate will provide more consistent results in cancer patients since Vitamin C blood levels attained are substantially higher in a range proven cytotoxic to malignant cells. In this article we will present and discuss our proposed mechanism on the chemotherapeutic activity exhibited by ascorbate.

Influence of pH and oxygen on copper corrosion in simulated uterine fluid

This paper studies the copper corrosion in simulated uterine fluids in the presence of urea and/or albumin, at pH 5.0, 6.3 and 8.0, with 0.10, 0.15 and 0.20 atmospheres of oxygen pressure and without additional oxygen pressure, at 37 degrees C temperature, and for 1, 3, 7, 15, 21 and 30 days experimentation. The copper dissolution rate was determined using absorbance measurements. Copper dissolution was the highest at pH 8.0 and 0.20 atmospheres of oxygen pressure, 674 microg d(-1) for 1 day and 109 microg d(-1) for 30 days. The presence of albumin, contrary to urea, accelerates copper corrosion.

Integrative medicine: a paradigm shift in medical education and practice

The use of alternative/complementary medicine has been increasing considerably. Conventional medicine must begin to address issues related to the use, safety, regulation, research and education of alternative/complementary medicine. Integrative medicine combines conventional medicine and alternative complementary practices. Integrative medicine is an innovative approach to medicine and medical education. It involves the understanding of the interaction of the mind, body and spirit and how to interpret this relationship in the dynamics of health and disease. Integrative medicine shifts the orientation of the medical practice from disease based approach to a healing based approach. It does not reject conventional medicine nor uncritically accepts unconventional practices. Integrative medicine is an effective, more fulfilling human approach to medicine based on the benefit of the patient by following good medicine practices in a scientific manner.

Aggressive therapy for locoregional recurrence after mastectomy in stage II and III breast cancer patients

BACKGROUND

To determine if aggressive treatment of locoregional recurrence affects survival, we retrospectively analyzed the clinical outcome of 69 breast cancer patients who developed locoregional disease as their first episode of recurrence following mastectomy and adjuvant chemotherapy.

METHODS

Patients were identified from among 1,707 stage II and III breast cancer patients who enrolled in five different doxorubicin-based adjuvant chemotherapy protocols at The University of Texas M. D. Anderson Cancer Center from 1975 to 1986. Sixty-nine evaluable patients who had a locoregional recurrence as the first site of relapse after mastectomy formed the study group. Multifactorial analysis of clinical and histopathological characteristics of both the primary tumor and the subsequent recurrence was performed using a logistic regression method. Survival analysis was performed using an actuarial life-table method calculated from the date of registration into the adjuvant therapy protocols.

RESULTS

Median follow-up was 6.6 years. Two factors significantly affected survival: recurrence of disease during or after adjuvant treatment of the primary and whether the patient was rendered disease free after recurrence.

CONCLUSIONS

Stage II and III breast cancer patients who have locoregional recurrence after adjuvant chemotherapy and can be rendered disease free may have a better survival rate. Aggressive treatment of locoregional recurrence including complete surgical excision should be considered in this subgroup of patients.

Enteric bacteria and ingested inert particles translocate to intraperitoneal prosthetic materials

Sterile and endotoxin-free biomaterials commonly used in prosthetic devices (Dacron velour, woven Dacron, and Biomer polyurethane) and cotton (control material) were implanted intraperitoneally in mice with normal enteric flora. Intraperitoneal Biomer and woven Dacron became contaminated with 100 to 10,000 enteric bacteria, including Escherichia coli, Pseudomonas aeruginosa, enterococci, and staphylococci species, within 3 days; intraperitoneal cotton and Dacron velour were contaminated within 24 hours. Mesenteric lymph nodes showed parallel incidences of translocation. The peritoneal cavity became contaminated only if the biomaterial itself became contaminated. No bacterial overgrowth, perforation, or histologic changes in the bowel were found. Subcutaneous biomaterials remained sterile. Ingested fluorescent beads appeared in enterocytes, in lamina propria within macrophages, and in intraperitoneal biomaterials. The data suggest that intraperitoneal sterile reactive stimuli can induce bacterial translocation to the dense prosthesis directly through the intact normal bowel wall. One of the mechanisms seems to involve phagocytosis of particles and bacteria within the bowel wall that are then chemotactically attracted to nearby sites of inflammation.

Biomaterial associated impairment of local neutrophil function

The effect of biomaterials on neutrophil function was studied in vitro to determine if these materials activated neutrophils and to determine the subsequent response of these neutrophils to further stimulation. Two biomaterials--polyurethane, a commonly used substance, and Velcro pile (used in the Jarvik 7 heart)--were evaluated. Two control substances, polyethylene and serum-coated polystyrene, were used for comparison. Neutrophil superoxide release was measured following incubation with these materials for 10, 30, and 120 min in the absence of additional stimulation and after stimulation with formylmethionylleucylphenylalanine (fMLP) or phorbol myristate acetate (PMA). The authors observed that the incubation of neutrophils on both polyurethane and Velcro resulted in substantially increased superoxide release that was greater after the 10 min than after the 30 or 120 min association. These activated neutrophils exhibited a poor additional response to fMLP but responded well to PMA. The effect of implantation of the Novacor left ventricular assist device on peripheral blood neutrophil function was also evaluated. The peripheral blood neutrophils exhibited normal superoxide release and chemotaxis. These studies suggest that biomaterials may have a profound local effect on neutrophils, which may predispose the patient to periprosthetic infection, but that the reactivity of circulating neutrophils is unimpaired.