DNA synthesis; DNA alkylation

With sham treatment, TTc transport causes fluorescent signal intensity over the thoracic spine to increase from 0 to 60 minutes after injection. On average, fluorescence signal increased 722%+/-117% (Mean+/-SD) from 0 to 60 minutes. Oxaliplatin treated animals had comparable transport at baseline (787%+/-140%), but transport rapidly decreased through the course of the study, falling to 363%+/-88%, 269%+/-96%, 191%+/-58%, 121%+/-39%, 75%+/-21% with each successive week and stabilizing around 57% (+/-15%) at 7 weeks. Statistically significant divergence occurred at approximately 3 weeks (p≤0.05, linear mixed-effects regression model). Quantitative immuno-fluorescence histology with a constant cutoff threshold showed reduced TTc in the spinal cord at 7 weeks for treated animals versus controls (5.2 Arbitrary Units +/-0.52 vs 7.1 AU +/-1.38, p<0.0004, T-test). There was no significant difference in neural cell mass between the two groups as shown with NeuN staining (10.2+/-1.21 vs 10.5 AU +/-1.53, p>0.56, T-test). Conclusion: We show-for the first time to our knowledge-that neurographic in vivo molecular imaging can demonstrate imaging changes in a model of oxaliplatin-induced neuropathy. Impaired retrograde neural transport is suggested to be an important part of the pathophysiology of oxaliplatin-induced neuropathy. [6]

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Oxaliplatin, administered intraperitoneally (i.p.) once a week at a dose of 10 mg/kg, dramatically lowers the tumor volume and apoptotic index in nude mice with hepatocellular HCCLM3 tumors. T-leukemia-lymphoma L40 AKR response to Oxaliplatin (5 mg/kg, i.v. on days 1, 5, and 9) is 1.77 T/C. Additionally, Oxaliplatin works well on xenografts of B16 melanoma, MA 16-C melanoma, Lewis lung xenografts, C26 colon carcinoma, and intracerebrally grafted L1210 leukemia. n mice, Oxaliplatin causes impairment of retrograde neuronal transport.

The sulforhodamine-B microculture colorimetrie assay is used to conduct the cytotoxicity investigations. The sulforhodamine-B test is typically conducted 48 hours after the cells (RT4, TCCSUP, A2780, HT-29, U-373MG, U-87MG, SK-MEL-2, and HT-144 cell lines) are plated into 96-well plates on day 0 and exposed to oxaliplatin on day 1. Except for when adding oxaliplatin and during the final assay period, the plates are always incubated at 37 °C in 5% CO2 and 100% relative humidity. The assay started with 2–20 × 103 cells/50 nL/well plated on a slide. On the day of the assay, the cells in control wells must still be in the log phase of growth; the maximum absorbance for the untreated controls must fall between 1.0 and 1.5; and the cells must undergo more than two doublings during the drug exposure. These criteria are based on pilot studies. A concentration is made up of eight wells. Using an IBM PC-compatible computer as the interface, a Biotek Instruments model EL309 microplate reader is used to read the plates at 570–540 nm. The computer program DATALOG transfers the data and converts it into a LOTUS 1-2-3 format. The drug treated and control are compared to determine the survival fractions.

Mice (n = 8/group) were injected with a cumulative dose of 30 mg/kg oxaliplatin (sufficient to induce neurotoxicity) or dextrose control injections. Intramuscular injections of Tetanus Toxin C-fragment (TTc) labeled with Alexa 790 fluorescent dye were done (15 ug/20 uL) in the left calf muscles, and in vivo fluorescent imaging performed (0–60 min) at baseline, and then weekly for 5 weeks, followed by 2-weekly imaging out to 9 weeks. Tissues were harvested for immunohistochemical analysis.[6]

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Researchers used two groups of 8 BALB/C mice for imaging studies: controls and oxaliplatin treatment (16 animals total for imaging studies). An additional two groups of 4 animals each were used for histological studies (8 animals total for histology), euthanized 7 weeks after starting the oxaliplatin regimen. Using a well-characterized model system described in the literature, experimental animals received Oxaliplatin dissolved in sterile water at 1 mg/ml (diluted as needed in 5% glucose) at a dose of 3 mg/kg per intra-peritoneal injection (0.2 ml total) for 5 days during the first week, followed by a 7 day rest, followed by another series of 5 daily injections in the third week. The total dose was 30 mg/kg cumulative, spread out over 10 injections given in two cycles. Control animals received 5% glucose sham injections. Animal weights were determined once a week at the end of the week prior to injections.[6]

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Dissolved in water; 10 mg/kg; i.p. injection.

Human hepatocellular carcinoma xenografts HCCLM3

Absorption
The active oxaliplatin derivative exists in plasma ultrafiltrate as a fraction of the free platinum. Two hours after a single intravenous infusion of oxaliplatin 85 mg/m², the pharmacokinetic parameter, expressed as ultrafiltration platinum, is Cmax 0.814 mcg/mL. The inter-patient and intra-patient variability in ultrafiltration platinum exposure (AUC0–48hr) assessed over three treatment cycles was 23% and 6%, respectively.
Elimination Route
The primary route of platinum elimination is renal excretion. Five days after a single intravenous infusion of ELOXATIN 2 hours later, approximately 54% of platinum is eliminated in the urine, and only about 2% in the feces.
Volume of Distribution
Two hours after a single intravenous infusion of oxaliplatin 85 mg/m², the volume of distribution is 440 L. After the 2-hour infusion, approximately 15% of the administered platinum enters the systemic circulation. The remaining 85% is rapidly distributed to tissues or excreted in the urine.
Clearance
The rate of platinum clearance from plasma (10⁻¹⁷ L/h) is similar to or higher than the mean human glomerular filtration rate (GFR; 7.5 L/h). Renal clearance of platinum via ultrafiltration is significantly correlated with GFR.

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Metabolism/Metabolites
Oxaliplatin undergoes rapid and extensive non-enzymatic biotransformation. No evidence of cytochrome P450-mediated metabolism has been found in vitro. Up to 17 platinum-containing derivatives have been observed in ultrafiltrate samples from patients, including several cytotoxic substances (platinum monochlorodihydrogen, platinum dichlorodihydrogen, platinum monohydrate, and platinum dihydrogen disohydrate) and several non-cytotoxic conjugates.

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Biological Half-Life
Following oxaliplatin administration, the decrease in platinum concentration in the ultrafiltrate is triphasic, including two distribution phases: t1/2α; 0.43 h and t1/2β; 16.8 h. This was followed by a relatively long terminal elimination phase (t1/2γ) lasting 391 hours.

Hepatotoxicity
A significant proportion of patients taking oxaliplatin experience a mild and transient increase in serum transaminase levels, but the relationship between this and oxaliplatin is usually unclear. Oxaliplatin chemotherapy is associated with histological changes in the liver, characterized by sinusoidal dilatation, congestion, and central lobule necrosis, suggesting sinusoidal obstruction syndrome. These changes are usually mild to moderate and clinically insignificant in the acute phase, but can progress to clinically significant sinusoidal obstruction syndrome, or develop into nodular regenerative proliferative disease (NRPD) after long-term treatment, accompanied by splenomegaly, thrombocytopenia, and esophageal varices. NRPD typically takes 6 to 18 months to develop and often occurs after multiple oxaliplatin chemotherapy sessions. Serum enzyme and bilirubin elevations are mild; the main laboratory finding is progressive and persistent thrombocytopenia, reflecting the development of splenomegaly and portal hypertension. The initial clinical manifestations of NRPD may be ascites, esophageal variceal bleeding, or hepatic encephalopathy. Hepatectomy, severe gastrointestinal bleeding, and sepsis can induce liver decompensation and liver failure. Interestingly, nodular regenerative proliferative disease and portal hypertension tend to improve slowly once chemotherapy is discontinued, but the long-term consequences of these changes are unclear. Probability score: A (Clinically evident cause of liver injury). Protein binding: Platinum-based drugs exhibit irreversible plasma protein binding in patients, exceeding 90%. The main binding proteins are albumin and gamma globulin. Platinum can also irreversibly bind to and accumulate in erythrocytes (approximately 2-fold), but appears to have no significant activity within erythrocytes. No platinum accumulation was observed in plasma ultrafiltrate following administration of 85 mg/m² platinum every two weeks.

[1]. Oxaliplatin: a review of preclinical and clinical studies. Ann Oncol. 1998 Oct;9(10):1053-71.

[2]. Oxaliplatin is active in vitro against human melanoma cell lines: comparison with NSC 119875 and NSC 241240. Anticancer Drugs. 2000 Nov;11(10):859-63.

[3]. In vitro cytotoxicity, protein binding, red blood cell partitioning, and biotransformation of oxaliplatin. Cancer Res. 1993 Dec 15;53(24):5970-6.

[4]. Oxaliplatin induces apoptosis in hepatocellular carcinoma cells and inhibits tumor growth. Expert Opin Investig Drugs. 2009 Nov;18(11):1595-604.

[5]. Oxalato-platinum or 1-OHP, a third-generation platinum complex: an experimental and clinical appraisal and preliminary comparison with cis-platinum. Biomed Pharmacother. 1989;43(4):237-50.

[6]. Impairment of retrograde neuronal transport in oxaliplatin-induced neuropathy demonstrated by molecular imaging. PLoS One. 2012;7(9):e45776. doi: 10.1371/journal.pone.0045776. Epub 2012 Sep 20.

[7]. Phenanthriplatin, a monofunctional DNA-binding platinum anticancer drug candidate with unusual potency and cellular activity profile. Proc Natl Acad Sci U S A. 2012 Jul 24;109(30):11987-92.

[8]. Comparative proteomic analysis of colon cancer cells in response to oxaliplatin treatment. Biochim Biophys Acta. 2009 Oct;1794(10):1433-40.

[9]. Capecitabine, Oxaliplatin, and Bevacizumab (BCapOx) Regimen for Metastatic Colorectal Cancer. Hosp Pharm. 2017 May;52(5):341-347.

Oxaliplatin is an organoplatinum complex in which platinum atoms are complexed with 1,2-diaminocyclohexane and oxalate ligands. The oxalate ligands are substituted to form active oxaliplatin derivatives. These derivatives form inter- and intra-strand crosslinks in DNA, thereby inhibiting DNA replication and transcription. Oxaliplatin is an antitumor drug, often used in combination with fluorouracil and leucovorin to treat metastatic colorectal cancer.
See also: Oxaliplatin (note moved to).

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Among the new generation of platinum compounds evaluated, compounds with 1,2-diaminocyclohexane as a carrier ligand (including oxaliplatin) have received considerable attention in recent years. Molecular biological studies and in vitro cytotoxicity screening by the National Cancer Institute have shown that diaminocyclohexane platinum drugs (such as oxaliplatin) belong to a unique family of cytotoxic drugs, unlike cisplatin and carboplatin, with specific intracellular targets, mechanisms of action, and/or resistance mechanisms. In a Phase I clinical trial, oxaliplatin's dose-limiting toxicities were transient acute paresthesia and cumulative distal neurotoxicity, which were reversible within months of discontinuation. Furthermore, at the recommended dose (130 mg/m² every three weeks; or 85 mg/m² every two weeks, administered intravenously over two hours), oxaliplatin did not demonstrate any dose-limiting toxicities in terms of hearing, kidneys, or hematology. A Phase II clinical trial evaluating the antitumor activity of oxaliplatin is currently underway in hundreds of patients with advanced colorectal cancer (ACRC). The overall objective response rate (ORR) for monotherapy in ACRC patients was 10% in previously treated/refractory 5-fluorouracil (5-FU) ACRC patients and 20% in previously untreated ACRC patients. Preclinical studies have shown that oxaliplatin has synergistic cytotoxic effects with thymidine synthase inhibitors, cisplatin/carboplatin, and topoisomerase I inhibitors, without hematologic dose-limiting toxicities, making oxaliplatin an ideal choice for combination therapy. In a phase II clinical trial of oxaliplatin in combination with 5-FU and leucovorin in previously treated/refractory ACRC patients, the overall response rate ranged from 21% to 58%, with a median survival of 12 to 17 months. In previously untreated ACRC patients, the treatment regimen of oxaliplatin in combination with 5-FU and leucovorin showed a response rate ranging from 34% to 67%, with a median survival of 15 to 19 months. Two randomized controlled trials, enrolling a total of 620 previously untreated ACRC patients, compared the efficacy of 5-fluorouracil (5-FU) in combination with leucovorin versus 5-FU in combination with leucovorin and oxaliplatin. The results showed that in the first trial, the overall response rate was 34% in the oxaliplatin group and 12% in the 5-FU plus leucovorin group; in the second trial, the overall response rates were 51.2% and 22.6%, respectively. These statistically significant differences were also reflected in the time to disease progression advantage in the oxaliplatin group (8.7 months vs. 6.1 months and 8.7 months vs. 6.1 months, respectively). A small number of persistent histological complete responses have been reported in patients with advanced colorectal cancer treated with oxaliplatin plus 5-FU plus leucovorin, and oncologists familiar with this combination regimen are increasingly performing secondary metastasis resections. Based on preclinical and clinical reports showing that oxaliplatin has an additive or synergistic effect with a variety of anticancer drugs (including cisplatin, irinotecan, topotecan and paclitaxel), clinical trials of oxaliplatin in combination with other compounds have been initiated or are underway for tumor types (such as ovarian cancer, non-small cell lung cancer, breast cancer and non-Hodgkin's lymphoma) that have shown antitumor activity as monotherapy. Its monotherapy and combination therapy data in ovarian cancer confirm that it has no cross-resistance with cisplatin/carboplatin. Although the role of oxaliplatin in medical oncology is not fully understood, it appears to be an important new anticancer drug. [1] We have previously demonstrated the in vitro activity of cisplatin and carboplatin against human melanoma cell lines. These two drugs are important components of our chemotherapy regimen for the treatment of advanced metastatic melanoma. This article reports the in vitro activity of oxaliplatin against human melanoma cell lines compared with cisplatin and carboplatin. The results showed that oxaliplatin was active against both C32 and G361 cell lines, with IC50 values of 49.48 and 9.07 μM (1 hour of exposure), 9.47 and 1.30 μM (4 hours of exposure), and 0.98 and 0.14 μM (24 hours of exposure), respectively. In this in vitro system, oxaliplatin showed significantly better cytotoxic activity than carboplatin. With prolonged exposure time, its activity gradually approached that of cisplatin. In fact, after 24 hours of exposure, oxaliplatin showed significantly higher activity against G361 cell lines than cisplatin (p=0.0343). Oxaliplatin deserves clinical evaluation, both as a monotherapy and in combination with other anti-melanoma drugs. [2]

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This study investigated the in vitro cytotoxicity, protein binding, platinum distribution from whole blood to erythrocytes, platinum exchange from erythrocytes to plasma, and in vitro biotransformation in plasma of the novel non-nephrotoxic platinum analog oxaliplatin. Cytotoxicity studies were conducted on a range of human tumor cell lines derived from ovarian cancer (A2780, A2780/cp), bladder cancer (TCCSUP, RT4), colon cancer (HT-29), melanoma (SKMEL-2, HTB144), and glioma (U373MG and U87MG). The relative potency of the five platinum complexes was: oxaliplatin = tetraplatin > cisplatin > isopropylplatin > carboplatin. Oxaliplatin was effective against HT-29 cells and showed very low cross-resistance with cisplatin against A2780/cp cells. Two bladder cancer cell lines, two melanoma cell lines, and one of two glioblastoma cell lines were resistant to both oxaliplatin and tetraplatin. The cytotoxicity profiles of the oxaliplatin-tetraplatin and cisplatin-carboplatin groups showed statistically significant correlations according to Spearman's rank correlation test. Oxaliplatin exhibits protein binding similar to that of cisplatin and tetraplatin; 85-88% of the platinum in oxaliplatin (5, 10, or 20 μg/mL) binds to plasma proteins within 5 hours of administration, with a mean half-life of 1.71 ± 0.06 hours. When oxaliplatin is incubated with whole blood (5, 10, and 20 μg/mL), erythrocytes absorb 37.1 ± 2.1% of the total platinum (maximum absorption) within 2 hours, and this platinum cannot be exchanged into the plasma. Therefore, platinum bound to erythrocytes does not serve as a drug reservoir. In plasma, oxaliplatin remains unchanged at 0.5 hours, but at 1 hour, 30% of the total platinum in plasma appears in a peak with a retention time similar to that of dichloroplatin(II), the major biotransformation product of tetraplatin (trans-1,2-diaminocyclohexane). At 2 hours, (trans-1,2-diaminocyclohexane)dichloroplatin(II) and three other platinum-containing peaks were detected, but no unchanged oxaliplatin was detected. All platinum was eluted in a peak near the solvent front at 4 hours. The significant similarity in cytotoxicity between oxaliplatin and tetraplatin may be due to the formation of (trans-1,2-diaminocyclohexane)dichloroplatin(II) in the tissue culture medium. [3]

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Objective: Platinum-based chemotherapy drug oxaliplatin has broad antitumor activity. To date, there are no detailed data on the effects of oxaliplatin on hepatocellular carcinoma (HCC) cells. This study investigated the antiproliferative effects of oxaliplatin on HCCLM3 and Hep3B cells in vitro and in vivo. Methods: Cell viability was assessed by MTT assay, and apoptosis was assessed by flow cytometry and transmission electron microscopy. The expression of apoptosis-related proteins in HCCLM3 cells was assessed by microarray analysis, quantitative reverse transcription-PCR and Western blotting. This study also investigated the effects of oxaliplatin in vivo using a xenograft tumor model. Results showed that oxaliplatin inhibited the growth of HCCLM3 and Hep3B cells. Flow cytometry, transmission electron microscopy, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) analysis revealed that apoptosis is the main mechanism by which oxaliplatin inhibits tumor progression. Microarray analysis, quantitative reverse transcription PCR, and Western blot analysis further confirmed that during oxaliplatin-induced apoptosis, the expression of anti-apoptotic proteins Bcl-2 and Bcl-xL was downregulated, while the expression of the pro-apoptotic protein Bax was upregulated. Conclusion: The anti-proliferative effect of oxaliplatin on hepatocellular carcinoma cells is due to its induction of apoptosis. Therefore, oxaliplatin may be an effective drug for treating hepatocellular carcinoma, and its application warrants further investigation. [4]

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A novel platinum complex, oxaloplatin (l-OHP), has shown comparable efficacy to cisplatin at the same metal dose in experimental testing, and superior efficacy to carboplatin at lower metal doses; its efficacy against human tumors such as the testes and ovaries is comparable to other platinum analogs, and even better against melanoma and breast cancer; and it has no nephrotoxicity, cardiotoxicity, or mutagenicity, and very low hematologic and neurotoxicity. This article describes it and compares it with the aforementioned platinum complexes. Oxalic acid platinum, in combination with 5-fluorouracil (5-Fu), has provided significant remission in patients with colorectal cancer and has cured some inoperable gastric cancers. In combination with carboplatin, it has achieved a high cure rate in mice carrying the L1210 mutation, which is unattainable by any other combination of two drugs. [5]

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Colorectal cancer is one of the most common malignant tumors in the world. Oxaliplatin is a third-generation platinum compound that is widely used in clinical chemotherapy for colorectal cancer. Although the antitumor mechanism of oxaliplatin has been studied in recent years, little is known about the proteomic changes associated with cellular responses to this compound. In this study, we performed comparative proteomic analysis on three colon cancer cell lines (HT29, SW620, and LoVo) to investigate the overall changes in protein expression levels after oxaliplatin treatment. Two-dimensional gel electrophoresis combined with MALDI-TOF/TOF mass spectrometry analysis revealed 57, 48, and 53 differentially expressed proteins in the three cell lines (HT29, SW620, and LoVo), respectively, after oxaliplatin treatment. Among these, 21 proteins were expressed in all three cell lines. These overlapping proteins are involved in various cellular processes, such as apoptosis, signal transduction, transcription and translation, cellular structure and organization, and metabolism. Furthermore, Western blotting experiments confirmed the expression levels of ezrin (EZRI), heat shock protein β-1 (HSPB1), translational regulatory tumor protein (TCTP), and cell division control protein 2 homolog (CDC2). This is the first direct proteomic analysis of oxaliplatin-treated colon cancer cells. Several interesting proteins we discovered warrant further investigation, as they may play an important role in the antitumor effect of oxaliplatin. [8]

C8H14N2O4PT

397.29

397.06

C, 24.19; H, 3.55; N, 7.05; O, 16.11; Pt, 49.10

61825-94-3

9887053

White solid powder

193.6ºC at 760 mmHg

0.614

4

6

0

15

191

2

[Pt+2].[O-]C(C(=O)[O-])=O.N([H])([H])[C@]1([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[C@@]1([H])N([H])[H]

DRMCATBEKSVAPL-BNTLRKBRSA-N

InChI=1S/C6H12N2.C2H2O4.Pt/c7-5-3-1-2-4-6(5)8;3-1(4)2(5)6;/h5-8H,1-4H2;(H,3,4)(H,5,6);/q-2;;+2/t5-,6-;;/m1../s1

[(1R,2R)-2-azanidylcyclohexyl]azanide;oxalic acid;platinum(2+)

L-OHP; diaminocyclohexane oxalatoplatinum; oxalatoplatin; oxalatoplatinum; DTXSID0036760; Oxalato(trans-l-1,2-cyclohexanediamine)platinum(II); cis-oxalato-trans-l-1,2-diaminocyclohexaneplatinum(II); US brand name: Eloxatin Foreign brand names: Dacotin; Dacplat; Eloxatine; Abbreviations: 1OHP; LOHP; Code names: JM83; RP54780; SR96669.

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Note: Oxaliplatin is generally not recommended to be dissolved in DMSO, as platinum-based drugs are prone to deactivation in DMSO. Additionally, Oxaliplatin is not stable in solution and should be prepared immediately before use.

Solubility in Formulation 1: 1.92 mg/mL (4.83 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication (<60°C).

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Solubility in Formulation 2: 3.33 mg/mL (8.38 mM) in 5% w/v Glucose Solution (add these co-solvents sequentially from left to right, and one by one), clear solution; with ultrasonication.

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 (Please use freshly prepared in vivo formulations for optimal results.)