Chemotherapy for pain: reversing inflammatory and neuropathic pain with the anticancer agent mithramycin A.

ABSTRACT: The persistence of inflammatory and neuropathic pain is poorly understood. We investigated a novel therapeutic paradigm by targeting gene networks that sustain or reverse persistent pain states. Our prior observations found that Sp1-like transcription factors drive the expression of TRPV1, a pain receptor, that is blocked in vitro by mithramycin A (MTM), an inhibitor of Sp1-like factors. Here, we investigate the ability of MTM to reverse in vivo models of inflammatory and chemotherapy-induced peripheral neuropathy (CIPN) pain and explore MTM's underlying mechanisms. Mithramycin reversed inflammatory heat hyperalgesia induced by complete Freund adjuvant and cisplatin-induced heat and mechanical hypersensitivity. In addition, MTM reversed both short-term and long-term (1 month) oxaliplatin-induced mechanical and cold hypersensitivity, without the rescue of intraepidermal nerve fiber loss. Mithramycin reversed oxaliplatin-induced cold hypersensitivity and oxaliplatin-induced TRPM8 overexpression in dorsal root ganglion (DRG). Evidence across multiple transcriptomic profiling approaches suggest that MTM reverses inflammatory and neuropathic pain through broad transcriptional and alternative splicing regulatory actions. Mithramycin-dependent changes in gene expression following oxaliplatin treatment were largely opposite to and rarely overlapped with changes in gene expression induced by oxaliplatin alone. Notably, RNAseq analysis revealed MTM rescue of oxaliplatin-induced dysregulation of mitochondrial electron transport chain genes that correlated with in vivo reversal of excess reactive oxygen species in DRG neurons. This finding suggests that the mechanism(s) driving persistent pain states such as CIPN are not fixed but are sustained by ongoing modifiable transcription-dependent processes.

Severe Hepatotoxicity of Mithramycin Therapy Caused by Altered Expression of Hepatocellular Bile Transporters.

Mithramycin demonstrates preclinical anticancer activity, but its therapeutic dose is limited by the development of hepatotoxicity that remains poorly characterized. A pharmacogenomics characterization of mithramycin-induced transaminitis revealed that hepatotoxicity is associated with germline variants in genes involved in bile disposition: ABCB4 (multidrug resistance 3) rs2302387 and ABCB11 [bile salt export pump (BSEP)] rs4668115 reduce transporter expression (P < 0.05) and were associated with ≥grade 3 transaminitis developing 24 hours after the third infusion of mithramycin (25 mcg/kg, 6 hours/infusion, every day ×7, every 28 days; P < 0.0040). A similar relationship was observed in a pediatric cohort. We therefore undertook to characterize the mechanism of mithramycin-induced acute transaminitis. As mithramycin affects cellular response to bile acid treatment by altering the expression of multiple bile transporters (e.g., ABCB4, ABCB11, sodium/taurocholate cotransporting polypeptide, organic solute transporter α/ß) in several cell lines [Huh7, HepaRG, HepaRG BSEP (-/-)] and primary human hepatocytes, we hypothesized that mithramycin inhibited bile-mediated activation of the farnesoid X receptor (FXR). FXR was downregulated in all hepatocyte cell lines and primary human hepatocytes (P < 0.0001), and mithramycin inhibited chenodeoxycholic acid- and GW4046-induced FXR-galactose-induced gene 4 luciferase reporter activity (P < 0.001). Mithramycin promoted glycochenodeoxycholic acid-induced cytotoxicity in ABCB11 (-/-) cells and increased the overall intracellular concentration of bile acids in primary human hepatocytes grown in sandwich culture (P < 0.01). Mithramycin is a FXR expression and FXR transactivation inhibitor that inhibits bile flow and potentiates bile-induced cellular toxicity, particularly in cells with low ABCB11 function. These results suggest that mithramycin causes hepatotoxicity through derangement of bile acid disposition; results also suggest that pharmacogenomic markers may be useful to identify patients who may tolerate higher mithramycin doses. SIGNIFICANCE STATEMENT: The present study characterizes a novel mechanism of drug-induced hepatotoxicity in which mithramycin not only alters farnesoid X receptor (FXR) and small heterodimer partner gene expression but also inhibits bile acid binding to FXR, resulting in deregulation of cellular bile homeostasis. Two novel single-nucleotide polymorphisms in bile flow transporters are associated with mithramycin-induced liver function test elevations, and the present results are the rationale for a genotype-directed clinical trial using mithramycin in patients with thoracic malignancies.

Gene expression dynamics following mithramycin treatment: A possible model for post-chemotherapy cognitive impairment.

Chemotherapy-induced cognitive changes is a major burden on a substantial number of cancer survivors. The mechanism of this sequel is unknown. In this study, we followed long-term effects of early in life mithramycin (MTR) treatment on behaviour and on the normal course of alterations of gene expression in brain. Between post-natal days (PND) 7 and 10, male rats were divided into 2 groups, 1 receiving MTR (0.1 mg/kg s.c. per day) and the other receiving saline. At PND11, frontal cortex tissue samples were dissected from 4 rats from each group. At PND 65 the remaining rats underwent behavioural tests after which all the rats were decapitated and their prefrontal cortex incised. Rats treated transiently with MTR early in life, showed impairments in spatial working memory and anxious-like behaviour in adulthood. The immediate molecular effect of MTR was expressed in a limited number of altered genes of different unconnected trajectories, which were simultaneously distorted by the drug. In contrast, 3 months later we observed a change in the expression of more than 1000 genes that converged into specific cellular processes. Time-dependent gene expression dynamics of several genes was significantly different between treated and untreated rats. The differences in the total number of altered genes and in gene expression trends, immediately and long after MTR treatment cessation, suggest the evolution of a new cellular homeostatic set point, which can lead to behavioural abnormalities following chemotherapy treatment.

Chemotherapeutic stress mediated by certain antitumor antibiotics induces an atypical CD69+ surface phenotype in peripheral T-lymphocytes.

Surface antigen CD69 is a Type II integral membrane protein that is generally considered a cell activation marker expressed very early in the normal lymphocyte activation cascade. The conformation of this surface antigen suggests a putative role in transmembrane signal transduction, yet the precise function of this surface antigen has not been clearly elucidated. We had previously reported robust atypical CD69 expression in peripheral T-lymphocytes as concentration-dependent, phenotypic responses to actinomycin D-induced chemotherapeutic stress in the absence of secondary stimulation. Additional antitumor antibiotics were evaluated for inductive potential, and the incidence and respective magnitudes of this chemotherapeutic stress-induced shift in lymphocytic CD69 expression were assessed. Results indicated that atypical CD69 expression is a common response to chemotherapy drug-induced stress. Differences in the respective percentages of CD69 + T-lymphocytes, and the resulting numbers of CD69 surface antigens ultimately expressed by these cells, were documented following in vitro drug exposure. The effective drug concentrations required to mediate detectable shifts in the CD69+ phenotype differed among the selected drugs, as well, suggesting a concentration-dependent induction mechanism putatively related to drug modality. Static CD69 expression responses in CD3+ peripheral T-lymphocytes were also documented, which further suggests that the different intracellular modalities do not mediate proportional T-lymphocyte responses through elevated CD69 expression.

Possible severe thrombocytopenia associated with a single dose of plicamycin.

OBJECTIVE: To report a case of possible severe thrombocytopenia associated with administration of a single dose of plicamycin. CASE SUMMARY: A 73-year-old man with prostate cancer was admitted to the hospital with hypercalcemia (total serum calcium concentration 4.02 mmol/L) and a low baseline platelet count (152 x 10(9)/L). Because of his symptomatic hypercalcemia, he was treated with NaCl 0.9%, furosemide, oral inorganic phosphate, and a single dose of plicamycin (15 micrograms/kg). Five days after plicamycin administration his platelet count decreased to 52 x 10(9)/L, and continued to decrease further even after the transfusion of four units of platelets to a nadir of 7 x 10(9)/L (hospital day 20). A second transfusion produced a small increase in his platelet count. The patient's clinical status continued to deteriorate, however, and he subsequently died. DISCUSSION: Plicamycin and other drugs that may induce thrombocytopenia are reviewed. The time course between plicamycin administration and the development of thrombocytopenia in our patient is assessed. Other contributing factors such as a low baseline platelet count and advanced age are also addressed. CONCLUSIONS: It is likely that the severe thrombocytopenia experienced by our patient was caused by a single dose of plicamycin. Adjusting the dosage for a patient's renal function as well as close monitoring of the platelet count are necessary when administering this drug. We report this case to remind clinicians of the potential for the development of severe thrombocytopenia following administration of a single dose of plicamycin.

Plicamycin and pamidronate in symptomatic tumor-related hypercalcemia: a prospective randomized crossover trial.

We have conducted a randomized crossover comparative trial of a single-dose course of disodium (3-amino-1-hydroxypropylidene) bisphosphonate pentahydrate (pamidronate) and plicamycin in 48 patients with a first occurrence of tumor-related hypercalcemia. All patients had hypercalcaemia-associated symptoms and serum-calcium levels (corrected for total protein) greater than or equal to 2.80 mmol/l. Pamidronate and plicamycin were given concurrently with rehydration immediately after diagnosis of hypercalcaemia was made. Both agents lowered serum calcium levels significantly within 1 week, with 88% of the evaluable patients in the pamidronate group and 45% of those in the plicamycin group achieving normocalcemia (p less than 0.01). In the patients who received pamidronate, the duration of normocalcemia was longer (p less than 0.05) and there was a significant decrease in serum creatinine (p less than 0.05). Vomiting occurred in 8 of 22 evaluable patients (36%) who received plicamycin, but in none of 25 evaluable patients who received pamidronate (P less than 0.01). Phlebitis occurred at the infusion site in more of the pamidronate-treated patients (P less than 0.05). Hypocalcemia, which occurred in 8 of 25 evaluable patients (32%) in the pamidronate group and in 1 of 22 of those (5%) in the plicamycin group, was either clinically asymptomatic or mild, except in one pamidronate-treated patient. Overall, pamidronate was found to be more effective and better tolerated than plicamycin, thereby confirming results of previous studies that showed pamidronate to be an effective, simple, and safe agent for the relief of the morbidity associated with tumor-related hypercalcemia.

Nephrotoxicity from chemotherapy: prevention and management.

Among the most devastating effects of antineoplastic chemotherapy is nephrotoxicity. This article discusses the effects of plicamycin, methotrexate, mitomycin C, nitrosoureas, 5-azacytidine, cisplatin, ifosfamide, carboplatin, and gallium nitrate on kidney function when these drugs are used either alone or in combination with each other and/or other agents. The importance of adequate hydration during chemotherapy in preventing and reversing drug-induced nephrotoxicity is also discussed.

Failure of mithramycin to control the myeloid blast phase of chronic granulocytic leukemia: a report on nine patients and review of the literature.

After reports of the successful use of mithramycin and hydroxyurea in the myeloid blast phase of chronic granulocytic leukemia, we treated nine patients according to the protocol devised by Koller and Miller (1986). There were no complete responses, but one patient had a partial response with a transient return to the chronic phase. Of the remaining eight patients, two experienced lessening of bone pains, and one a reduction in spleen size, but without hematological improvement. The regimen was associated with significant toxicity, and no overall survival advantage. We present a review of published data regarding the use of mithramycin in chronic granulocytic leukemia which supports the results in our series. The combination of mithramycin and hydroxyurea is largely ineffective in the blast phase of chronic granulocytic leukemia, but may be of value in the accelerated phase.

[Myeloid crisis of chronic myelogenous leukemia showing dramatic response to mithramycin and hydroxyurea combination].

After 4 years of chronic phase, a 22-year-old female with Ph1 (+) chronic myelogenous leukemia developed myelomonocytic crisis. On admission, her Hb was 9.9 g/dl, Plt 4.1 x 10(4)/microliters, WBC 138,000/microliters with 16.5% blasts. Bone marrow contained 38% blasts. She received a combination chemotherapy of mithramycin and hydroxyurea, as reported by Koller et al. Dose of mithramycin was reduced to 20 micrograms/kg. Following 1st and 2nd infusions of mithramycin, severe nasal bleeding was seen. Prednisolone 10 mg/day was given from the 3rd dose of mithramycin with apparent hemostatic effects. Calcium gluconate 3 g/day was administered concomitantly. Her disease responded promptly to this treatment and hematological remission was achieved.

Phase II trial of plicamycin and hydroxyurea in acute myelogenous leukemia.

A total of 23 patients with high-risk acute myelogenous leukemia (AML) at diagnosis (2 patients), relapsing AML (14) or resistant AML (6) were treated with 25 micrograms/kg i.v. plicamycin every other day for 3 weeks and 500-4,000 mg hydroxyurea per day p. o. according to the WBC count. Aplasia was observed in only two patients. Severe extrahematologic toxicity included sepsis (four cases), vomiting (four patients), toxic hepatitis (three cases), and fibrinopenia (one patient). No partial or complete responses were observed. The 95% confidence interval limit of the overall response rate (CR + PR) was 0-14%.

Cardiac arrest associated with hypokalaemia in a patient receiving mithramycin.

The case is reported of a patient who developed severe hypokalaemia, leading to cardiac arrest, while receiving mithramycin for painful Paget's disease. The patient was also receiving antihypertensive and anti-anginal treatment including bendrofluazide, but plasma potassium before the administration of mithramycin was normal. Hypokalaemia has been reported in previous studies of the use of mithramycin but has received little attention. The drug should be used with great care in patients with cardiovascular disease and in those receiving diuretics.

Preliminary observations on the therapy of the myeloid blast phase of chronic granulocytic leukemia with plicamycin and hydroxyurea.

We observed a dramatic improvement in the peripheral blood counts of a patient in the myeloid blast phase of chronic granulocytic leukemia after plicamycin (mithramycin) therapy of concurrent hypercalcemia. We then treated eight additional patients in the blast phase of chronic granulocytic leukemia with a combination of alternate-day plicamycin and daily hydroxyurea. All six patients with myeloid morphology at the time of blast crisis responded with a return to a chronic phase without an intervening pancytopenic period. Of three patients with lymphoid morphology at the time of treatment, only one responded (this patient had recently relapsed and converted from myeloid to lymphoid morphology). Another patient with nonmyeloid, nonlymphoid blast morphology also did not respond. Continual therapy with the two-drug combination appeared to be necessary, since early relapses were seen in responding patients whose therapy was interrupted. These data are preliminary and will need further confirmation, but they suggest that the combination of alternate-day plicamycin and daily hydroxyurea may be effective in the myeloid blast phase of chronic granulocytic leukemia.

Acquired dysfibrinogenemia secondary to mithramycin toxicity.

A 58-year-old black woman with IgD multiple myeloma developed a hemorrhagic diathesis within 48 hours after receiving mithramycin (20 micrograms/kg/day) for therapy of hypercalcemia. Her coagulation studies were characterized by prolonged prothrombin, partial thromboplastin, thrombin, and reptilase clotting times. Her plasma and partially purified fibrinogen were inhibitory to the clotting of normal plasma and fibrinogen. The patient's isolated fibrinogen showed a normal rate of fibrinopeptide release, but her fibrin monomer aggregation was markedly abnormal. These studies document the development of a dysfibrinogenemia secondary to mithramycin toxicity.

Immobilization hypercalcemia following spinal cord injury.

Based on the author's experience with more than 20 cases of immobilization hypercalcemia following spinal cord injury, current concepts of this condition are presented. Symptoms may be mild or severe: laboratory findings are essential for differential diagnosis in older individuals, in whom preinjury Paget's disease and mild primary hyperparathyroidism must be ruled out. Most cases of immobilization hypercalcemia are seen in adolescent boys following recent spinal cord injury. Besides sex (male), risk factors include age (less than 21 years), complete neurologic injuries, high cervical levels of spinal cord injury, dehydration, and a prolonged period of immobilization. A preinjury history of large ingestion of milk and/or extreme exposure to sunshine may also be contributory factors. Therapy includes vigorous hydration, saline infusions and diuretics, calcitonin, and steroids. The clinical course, without treatment, may be prolonged to 14 months, but the condition is always self-limiting.

[Acute fatal hepatorenal failure during treatment with mithramycin]. / Insuffisance hépato-rénale aiguë mortelle au cours d'un traitement par la mithramycine.

A case of fatal hepato-renal failure occurring during mithramycin treatment is reported. A 64 year-old female patient was admitted to hospital in a state of acute renal failure. She also presented with hypercalcaemia and bilateral pulmonary metastases. She had been operated on 10 years previously of a parathyroid cancer. Despite treatment with mithramycin (total dose 8.25 mg) and haemodialysis, the hypercalcaemia returned; it was then decided to remove the secretory lung metastases (parathormone 420 micrograms X ml-1). 48 hours before surgery, the patient was again given 1.25 mg mithramycin. Immediately after surgery, she developed hepatic failure with massive cell destruction and anuria. The patient died 48 h after the operation. The hepatic and renal complications of mithramycin are discussed.

Hepatic toxicity of low doses of mithramycin in hypercalcemia.

The medical records of patients receiving mithramycin for the treatment of hypercalcemia at The Johns Hopkins Oncology Center were reviewed. Of 67 evaluable patients, 11 (16%) developed hepatic toxicity when graded using standard criteria. The pattern of laboratory abnormalities noted suggested mild hepatocellular damage that was reversible within 2 weeks. Review of these patients did not identify factors which predispose to hepatic toxicity, although failure to do so may reflect the limited number of toxic patients evaluated. Mild, reversible hepatic dysfunction appears to be a more common sequela of mithramycin administration than has previously been recognized.