Intravenous Ascorbate as a Chemotherapeutic and Biologic Response Modifying Agent
By The Center's Bio-Communications Research Institute
后来，我们检测接受IAA的病人的血清样本，并且证实了AA浓度可以达到对（体外）癌细胞有毒性的水平。使用密集生长的单层细胞、三维中空纤维肿瘤模型，以及人类血清作为培养基，以模拟发生在体内的环境。我们发现，400 mg/dL的浓度可以杀灭几乎所有类型的癌细胞。最初，我们报告40 mg/dL已经足够(3)。这些早期的资料从体外研究，使用稀疏生长的细胞层，以及标准培养基所得。
图1: Mia PaCa-2（人类胰腺癌）细胞系对抗坏血酸钠（12个样本的平均数）的反应。SK-MEL-28 (人类黑色素瘤), SW-620 (人类结肠癌),以及 U-2-OS (人类骨肉瘤)全部都来自ATCC, Rockville, MD。结果反映所有生存的细胞数。维持培养基是DMEM高葡萄糖培养基(Irvine Sci.)，+10%热灭活胎牛血清+抗生素+两性霉素B，5%CO2 湿润培养器，设在摄氏37度。实验培养基分别是来自诊断为各种肿瘤的病人的血清。在加入抗坏血酸钠后培养3天。在96个培养皿种入24000个癌细胞。活细胞的绝对数量使用之前描述的微板块荧光计方法测定(16)。
注释： Plasma ascorbate(mg/Dl)=血浆抗坏血酸浓度(mg/Dl); Time(minutes)=时间（分钟）
图2：65克抗坏血酸加入500毫升注射用水，以每分钟1克的速度的静脉滴注过程中的血清抗坏血酸浓度。全血是在接受输液的另一侧手臂的肘前静脉通过静脉留针取得的。血清AA浓度使用高敏感度液体色谱仪测定。患者1(Patient 1)是一名74岁男性，被诊断为没有发生转移的前列腺癌，他在这个研究前的过去的二年接受了超过30次IAA 静脉滴注。患者2(Patient 2)是一名50岁的男性，患有霍金氏淋巴瘤，在这个研究之前接受过16次IAA静脉滴注。患者3(Patient 3)是一名69岁的男性，患有空肠的转移性瘤，在这个研究前接受了16次IAA静脉滴注。
图2描述三个代表性病人给予65克抗坏血酸65分钟后的血清抗坏血酸水平。患者1患有局部性前列腺癌，已经临床治愈。并且在过去曾接受IAA治疗。他取得一个峰值血清浓度702 mg/dL。患者2和3，分别患有非霍金氏瘤和空肠的转移性瘤。在这个检测前，接受过几次IAA静滴，然而，取得更低的血清AA浓度309 mg/dL (患者 3)和396 mg/dL (患者 2)。
5. 因为抗坏血酸是一种螯合剂，某些人可能会因为血清钙水平低而出现抽搐。这个可以用缓慢(每分钟1 cc)静脉推注10 cc葡萄糖酸钙治疗。
9. 抗坏血酸应该只是由静脉滴注。它绝不应该经静脉推注，因为大剂量的同渗重摩可以令外周血管硬化，也不应该由肌肉或皮下注射。经常要衡量液体容量和同渗重摩的问题。我们发现一个小于1200 milliOsmal的同渗重摩（渗透压）可以被大多数病人耐受(表1，可以参看原文件). 。
表1各种不同数量的抗坏血酸钠/抗坏血酸在注射用水和林格氏乳酸液(mOsm; 等渗= 300 mOsm)的渗透压。高渗混合液加了下画线：使用的混合液从等渗~1200 mOsm，用粗字体表示。在加入浓缩的抗坏血酸钠/抗坏血酸溶液前(500 mg/mL)，一个相等容量的IV溶液从袋或瓶中抽取。
注释：Sodium Ascorbate=抗坏血酸钠; Ascorbic Acid=抗坏血酸; Final Volume of Sterile Water=注射用水最后容量 Final Volume of Ringer’s Lactate= 林格氏乳酸液最后容量
在大剂量抗坏血酸治疗中，很多静脉滴注溶液是属于高渗的。这并不表示会产生问题，只要滴注速度足够慢以及渗透压不超过1200 milliOsmal (mOsm)。AA的剂量小于15克，我们用林格氏乳酸液(RL)稀释。而更大的剂量，用注射用水稀释。我们现在使用一种抗坏血酸钠/抗坏血酸混合物，每1摩尔抗坏血酸包含0.91摩尔钠(500 毫克 抗坏血酸/毫升, pH 值5.5-7.0, 生产商: Merit Pharmaceuticals, Los Angeles, California, and Maclaskey Pharmaceuticals, Wichita, Kansas)。表1显示常用溶液的同渗重摩(渗透压)。
正如在注意事项指出的， 15克AA，溶于250 mL 格林氏液在1个小时内滴注完毕是建议的一个小的开始剂量。要密切关注病人可能出现的任何不良效果。然后，剂量逐渐增加。滴注速度不应超过每分钟1克AA；大多数人都可以耐受每分钟0.5克。虽然通常会由于日程安排和耐受程度不同而有变化，一个典型的方案将由以下滴注组成：
N-乙酰半胱氨酸(生产商:Vitamin Research Products, Carson City, NV)，500 毫克, 口服, 每天一次；
beta-1,3- 葡聚糖(一种巨噬细胞激活剂, 生产商: NSC-24, Nutrition Supply Corp., Carson City, NV), 2.5毫克，每次3片，口服，每天一次；
鱼油(超级EPA, 生产商:Bronson Pharmaceuticals, St. Louis, MO; 含300 mg二十烷王烯酸, 200 mg 二十二碳六烯酸), 1 粒，口服，每天三次；
beta-胡萝卜素 (Beta Carotene 25, 生产商: Miller Pharmacal Group, Inc., Carol Stream, IL), 每次25,000 单位，口服，每天二次；
L-苏氨酸(生产商:The Solgar Vitamin Co, Inc., Lynbrook, NY), 500毫克，口服每天一次 (纠正实验室检查血清发现的缺乏);
杆状乳酸菌(Lateroflora, International Bio-Tech U.S.A., San Marcos, CA), 280毫克，每次服2片，每天一次。治疗肠道酵母菌/念株菌感染；
复方肌醇烟酸酯 (生产商:Niaplex, Karuna Corp., Novato, CA; 含500 毫克 烟酸, 100 微克 铬)每次2片，口服，每天一次；
Intravenous Ascorbate as a Chemotherapeutic and Biologic Response Modifying Agent
by The Center for the Improvement of Human Functioning, International, Inc., Bio-Communications Research Institute. Reprinted with permission.
(Emphasis added by DoctorYourself.com editor Andrew Saul)
Additional research papers may be read athttp://brightspot.org/cresearch/index.shtml
For over 15 years we have studied high dose intravenous ascorbic acid (IAA) as an adjunctive therapy for cancer patients. Initially, doses of 15 g per infusion were used, once or twice per week. These doses improved patient's sense of well being, reduced pain, and in many cases prolonged life beyond prognostications of oncologists.
Twelve years ago, we used infusions of 30 grams of intravenous ascorbic acid, twice per week, and found that metastatic lesions in the lung and liver of a man with a primary renal cell carcinoma disappeared in a matter of weeks (1). At that time we believed IAA was useful for patients with cancer solely through two biological response modifier mechanisms: increased production of extracellular collagen ("walling off' the tumor as proposed by Cameron and Pauling) and enhancement of immune function. We subsequently reported a case of resolution of bone metastases in a patient with primary breast cancer (1A) using infusions of 100 grams, once or twice per week (2).
In a recent publication (3) we presented evidence that ascorbic acid and its salts (AA) could be more than biological response modifiers. We found that ascorbic acid is preferentially toxic to tumor cells suggesting that it could be useful as a chemotherapeutic agent. Preferential toxicity occurred in vitro in multiple tumor cell types. We also presented data suggesting that plasma concentrations of ascorbate required for killing tumor cells were achievable in humans. Others have described in vivo toxicity in multiple tumor types and animal models (4-8).
Here we wish to summarize our experience using IAA for approximately 50 patients with cancer. We include our protocol, precautions, and case studies of two patients treated for metastatic renal cell carcinoma.
From our studies (3) we concluded that:
Tumor cells are more susceptible to the effects of high-dose, ascorbate-induced peroxidation products because of a relative catalase deficiency; and,
Concentrations of ascorbate high enough to kill tumor cells likely can be achieved in humans.
Subsequently we tested samples of human serum from patients receiving IAA, and confirmed that AA concentrations can reach levels that are cytotoxic to tumor cells in vitro. Using densely populated monolayers, three-dimensional hollow-fiber tumor models, and human serum as a growth medium to closely mimic what occurs in vivo, we found that an AA concentration of 400 mg/dL effectively kills most tumor cell types. Originally we reported that a concentration of 40 mg/dL was adequate (3). Those early data were generated from in vitro studies using sparsely populated cell monolayers and standard tissue culture medium
Figure 1 (which may be seen in the original paper posted at http://brightspot.org/cresearch/intravenousc2.shtml) shows the responses to increasing doses of ascorbate of four human tumor cell lines grown in dense monolayers in a medium of human serum.
Figure 1 Caption:
Response to sodium ascorbate (mean of 12 samples) of tumor cell lines Mia PaCa-2 (human pancreatic carcinoma). SK-MEL-28 (human melanoma), SW-620 (human colon carcinoma), and U-2-OS (human osteogenic sarcoma), all from ATCC, Rockville, MD. Results reflect total viable cells. Maintenance medium was DMEM High-glucose culture medium (Irvine Sci.) wf 10% heat-inactivated fetal calf serum + antibiotics + Fungizone, 5% CO2 humidified incubator at 37 degrees C. Experimental medium was human serum from patients with diagnoses of respective human tumors. Cultured for 3 days after supplementation of ascorbate. Seeded with 24,000 celIs Avell in 96-well culture plates (Nune). Absolute quantitation of live cells determined using previously described microplate fluorometer method (16).
Figure 2 Caption:
Plasma ascorbate concentrations during infusion of 65 grams ascorbic acid in 500 ml sterile water at a rate of one gram AA per minute. Whole blood was taken via a heparin lock from the antecubital vein of the arm contraleral to the arm receiving the IV infusion. Plasma AA concentrations were determined using high performance liquid chromatograpy. Patient I was a 74-year-old male who had a diagnosis of non-metastatic prostate carcinoma, who had received more than 30 IAA infusions in the two years prior to the study. Patient 2 was a 50-year-old male with a diagnosis of non-Hodgkin's lymphoma who had received l6 IAA infusions prior to study. Patient 3 was a 69 year old male with a diagnosis of metastatic carcinoma of the jejunum who had received 16 IAA infusions prior to study.
Figure 2 depicts plasma ascorbate levels of three representative patients given 65 grams of ascorbate over 65 minutes. Patient 1 with localized prostate cancer was clinically well and had received IAA in the past; he achieved a peak plasma concentration of 702 mg/dL. Patients 2 and 3, had diagnoses of non-Hodgkin's lymphoma, and metastatic carcinoma of the jejunum, respectively. Both had received several IAA infusions at the time of study, yet achieved lower plasma AA concentrations of 309 mg/dL (patient 3), and 396 mg/dL (patient 2).
From the data in both Figures 1 and 2, one can see that the concentrations required to kill tumor cells can be achieved at least briefly in human plasma. Figure 2 suggests the need to measure post-IAA plasma ascorbate concentrations to determine if patients are achieving what we expect are adequate concentrations.
Treatment of cancer with IAA should never be considered to replace an effective, proven treatment. It should only be considered in:
Cases of treatment failure using proven methods cases with no known effective treatments; and,
Cases in which it is used as an adjunct to proven treatments.
Because IAA treatment is experimental an appropriate informed consent form should be read, understood, and signed by the patient.
Precautions and side effects
The side effects of IAA in our experience are rare. However, there are contraindications and potential side effects to be considered.
1. Although it has been reported only once in the literature, tumor necrosis, hemorrhage, and subsequent death after a single intravenous 10 gram dose of AA, as reported by Campbell and Jack (10), should be the highest priority concern for the safety of IAA for cancer patients. For this reason, we always begin with a small dose (see Infusion).
2. Another report described acute oxalate nephropathy in a patient with bilateral ureteric obstruction and renal insufficiency who received 60 gram IAA (11). We have also heard one case report of a patient with colon carcinoma, receiving daily IAA, who developed nausea and vomiting and was hospitalized for dehydration (12). Both cases show the need to ensure that patients have adequate renal function, hydration, and urinary voiding capacity. To these ends, our baseline lab tests include a serum chemistry profile and urinalysis.
3. Hemolysis can occur in patients with a red cell glucose-6-phosphate dehydrogenase (G6PD) deficiency. We therefore test G6PD on all patients before beginning IAA infusions.
4. Localized pain at the infusion site can occur if the infusion rate is too high. This is usually corrected by slowing the rate.
5. Because ascorbate is a chelating agent, some individuals may experience shaking due to low serum calcium. This is treated by a slow (1 cc per minute) intravenous push of 10 cc's of calcium gluconate.
6. Rivers (13) reported that high dose IAA is contraindicated in renal insufficiency, chronic hemodialysis patients, unusual forms of iron overload, and oxalate stone formers. However, oxalate stone formation may be considered a relative contraindication. Two groups of researchers (14,15) demonstrated that magnesium oxide (300 rng/d orally) and vitamin B6 (10 mg/d orally) inhibited oxalate stone formation in stone formers.
7. Given the amount of fluid which is used as a vehicle for the ascorbate and the sodium hydroxide/sodium bicarbonate used to adjust the pH, any condition which could be adversely affected by increased fluid or sodium is relatively contraindicated. For example: congestive heart failure, ascites, edema, etc.
8. As with any intravenous site, infiltration is always possible.
9. Ascorbate should only be given by intravenous drip. It should never be given IV push, as the osmolality of high doses are capable of sclerosing peripheral veins, nor should it be given intramuscularly or subcutaneously. There is always a trade-off between fluid volume and osmolality. We have found an osmolality of less than 1200 milliOsmal to be tolerated well by most patients (Table 1, which may be seen in the original paper).
Prior to administering large quantities of ascorbate, we gather the following information for a baseline and as a way to monitor therapy:
Serum chemistry profile with electrolytes
Complete blood count with differential
Red blood cell G6PD
Appropriate serum tumor markers
Appropriate CT, MRL, bone scans, and x-ray imaging
Table 1 Caption:
Osmolality of various amounts of sodium ascorbate/ascorbic acid in sterile water and Ringer's Lactate (mOsm; isotonic = 300 mOsm). Hypotonic mixtures are underlined: useful mixtures from isotonic to 1200 mOsm are in bold. An equal volume of IV solution is removed from the bag or bottle, prior to adding concentrated sodium ascorbate/ascorbic acid solution (500 mg/mL).
In high-dose ascorbate therapy, many intravenous solutions are hypertonic. This does not seem to present a problem as long as the infusion rate is low enough and the tonicity does not exceed 1200 milliOsmal (mOsm). We generally infuse AA mixed with Ringer's lactate (RL) solution for AA amounts up to 15 gram, and in sterile water for larger amounts of AA. We presently use a sodium ascorbate/ascorbic acid mixture Containing 0.91 moles of sodium per mole of ascorbate (500 mg AA/mL, pH range 5.5-7.0, Merit Pharmaceuticals, Los Angeles, California, and Maclaskey Pharmaceuticals, Wichita, Kansas). Table I shows the osmolalities of commonly prepared solutions.
As indicated in the precautions, a small starting dose of 15 gram AA in 250 mL RL over 1 hr is recommended. The patient is watched closely for any adverse effects. The dose can then be gradually increased over time. The infusion rate should not exceed 1 gram AA per minute; 0.5 gram/mm is well tolerated by most patients. Although there is variability due to scheduling and tolerance, a typical protocol will consist of the following infusions:
Week 1: 1 x 15 g infusion per day, 2-3 per week
Week 2: 1 x 30 g infusion per day, 2-3 per week
Week 3: 1 x 65 g infusion per day, 2-3 per week
The dose is then adjusted to achieve transient plasma concentrations of 400 mg/dL, 2-3 infusions per week.
According to our working hypothesis, the goal of the infusions is to raise plasma ascorbate concentration above the tumor-cytotoxic level for as long as possible. Because the ascorbate is so readily cleared by the kidney, the optimal infusion rate will result in tumor-cytotoxic plasma levels of ascorbate for the longest time periods--and hopefully, maximum tumor cell killing.
We advise patients to orally supplement with 4 grams ascorbate daily, especially on the days when no infusions are made, to help prevent a possible scorbutic "rebound effect."
We have seen patients with almost every type of solid tumor in our clinic. Many of them have received IAA, with various degrees of success. Our cases include a patient with cancer of the head of the pancreas who lived for 3.5 years with IAA as sole therapy, resolution of bone metastases in patients with breast cancer, many patients with non-Hodgkin's lymphoma (none of whom have died from their disease), resolution of primary liver carcinoma tumors, resolution of and reduction in size of metastatic colon carcinoma lesions, and resolution of metastatic lesions and over 3-year survival in patients with widely metastatic ovarian carcinoma. We plan to present a full compilation of cases in another communication.
We have seen only two cases of metastatic renal cell carcinoma, considered a uniformly untreatable disease. Because the results were so dramatic, people with this disease could potentially benefit the most from IAA treatment.
Following are those two cases.
A 52-year-old white female with a history of renal cell carcinoma was seen in our clinic for the first time in October, 1996.In September 1995, shortly after diagnosis of a primary tumor in her left kidney, a nephrectomy was performed. Histology confirmed renal cell carcinoma. No evidence of metastases was found at that time. In March 1996, metastases to the lungs were found on chest x-ray film. In September 1996, a chest x-ray film revealed 4 1- to 3-cm masses in her lungs. One month later there were 8 1- to 3-cm masses in her lungs (7 in right lung, 1 in left).No new medical, radiation, or surgical therapies were performed prior to her visit to our clinic in October 1996, when she began IAA therapy. Her initial dose was 15 g, which increased to 65 g after 2 weeks, two per week. She was also started on: N-acetyl cysteine (Vitamin Research Products, Carson City, NV), 500 mg 1 p.o., QD; beta-1,3- glucan (a macrophage stimulator, NSC-24, Nutrition Supply Corp., Carson City, NV), 2.5 mg 3 p.o. QD; fish oil (Super-EPA, Bronson Pharmaceuticals, St. Louis, MO; 300 mg eicosatetraenoic acid, 200 mg docosahexaenoic acid), 1 p.o. TID; vitamin C, 9 g p.o. QD; beta-carotene (Beta Carotene 25, Miller Pharmacal Group, Inc., Carol Stream, IL), 25,000 lU. 1 p.o. BID; L-threonine (The Solgar Vitamin Co, Inc., Lynbrook, NY), 500 mg p.o. QD (for a deficiency revealed by laboratory testing of serum); Bacillus laterosporus (Lateroflora, International Bio-Tech U.S.A., San Marcos, CA), 280 mg, 2 p.o. QD for intestinal Candida a/b icans, inositol hexaniacinate complex (Niaplex, Karuna Corp., Novato, CA; 500 mg niacin, 100 mcg chromium) 2 p.o. QD, and a no-refined-sugar diet.
She continued IAA treatments until June 1997 when another chest x-ray film revealed resolution of 7 of the 8 masses, and reduction in the size of the 8th. According to the medical imaging report, "The nodular infiltrates seen previously in the right lung and overlying the heart are no longer evident and the nodular infiltrate seen in left upper lung field has shown marked Interval decrease in size and only vague suggestion of an approximately I cm density."
The patient discontinued IAA treatments in June 1997. She has continued on an oral nutritional support program since that time, and at this writing (December 1997) is well with no evidence of progression.
In December 1985, a mass occupying the lower pole of the right kidney was discovered in a 70- year-old white male. Pathology of the mass after a radical nephrectomy confirmed renal cell carcinoma. He was followed by an oncologist at another clinic. Approximately three months after surgery, the patient's x-ray film and CT scan showed "multiple pulmonary lesions and lesions in several areas of his liver which were abnormal and periaortic lymphadenopathy."
In March 1986 the patient was seen in our clinic (1). He decided not to undergo
chemotherapy. Vie requested and was started on IAA, 30 g twice per week. In April 1986, six weeks after the x-ray film and CT scan studies, the oncologist's report stated,
". . . the patient returns feeling well. His exam is totally normal. His chest x-ray shows a dramatic improvement in pulmonary nodules compared to six weeks ago. The periaortic lymphadenopathy is completely resolved..., either he has had a viral infection with pulmonary lesions with lymphadenopathy that has resolved or (2) he really did have recurrent kidney cancer which is responding to your vitamin C therapy."
The oncology report in July 1996 stated, "there is no evidence of progressive cancer. He looks well . . . chest x-ray today is totally normal. The pulmonary nodules are completely gone. There is no evidence of lung metastasis, liver metastasis or lymph node metastasis today, whatsoever."
In 1986 the patient received 30 g infusions twice-weekly for 7 months. The treatments were then reduced to once per week for 8 more months. For an additional 6 months he received weekly, 15 g IAA infusions. During and after treatments, the patient reported no toxicities, and his blood chemistry profiles and urine studies were normal. The patient continued well, and was seen periodically at our clinic until early 1997 when he died, cancer-free, at age 82, 12 years after diagnosis.
We believe that IAA has potential as a chemotherapeutic agent. We hope our protocols for mixing and infusion of IAA, precautions to be taken before and during its use, and clinical case reports will justify further clinical trials and research with IAA for patients with metastatic disease. We do not believe it is a cure for all cancers. Although it shows promise as a sole therapy, particularly in renal cell carcinoma, it should be used primarily as an adjunct to other effective therapies.
Our research is funded solely through donations from individuals. We have neither sought nor received funding from government agencies. We encourage readers to support our research. All donations to our 501 (C) 3 organization are tax-deductible.
Neil H. Riordan, PA-C
Hugh D. Riordan, M.D.
Ronald E. Hunninghake, M.D.
The Center for the Improvement of Human Functioning, International, Inc.
3100 N. Hillside Ave., Wichita, Kansas 67219
We would like to thank the Bio-Communications Research Institute scientific staff who contributed to this research: Neil Riordan, P.A.-C., Xiaolong Meng, MB.; Paul Taylor, B.S.; Jei Zhong, MB.; Kevin Alliston, MS.; and Joseph Casciari, Ph.D. We thank Don R. Davis, Ph.D., for editing this manuscript.
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