Comparative Proteomic Analysis Identifies Key Metabolic Regulators of Gemcitabine Resistance in Pancreatic Cancer

Pancreatic adenocarcinoma (PDAC) is highly refractory to treatment. Standard-of-care gemcitabine (Gem) provides only modest survival benefits, and development of Gem resistance (GemR) compromises its efficacy. Highly GemR clones of Gem-sensitive MIAPaCa-2 cells were developed to investigate the molecular mechanisms of GemR and implemented global quantitative differential proteomics analysis with a comprehensive, reproducible ion-current-based MS1 workflow to quantify ∼6000 proteins in all samples. In GemR clone MIA-GR8, cellular metabolism, proliferation, migration, and 'drug response' mechanisms were the predominant biological processes altered, consistent with cell phenotypic alterations in cell cycle and motility. S100 calcium binding protein A4 was the most downregulated protein, as were proteins associated with glycolytic and oxidative energy production. Both responses would reduce tumor proliferation. Upregulation of mesenchymal markers was prominent, and cellular invasiveness increased. Key enzymes in Gem metabolism pathways were altered such that intracellular utilization of Gem would decrease. Ribonucleoside-diphosphate reductase large subunit was the most elevated Gem metabolizing protein, supporting its critical role in GemR. Lower Ribonucleoside-diphosphate reductase large subunit expression is associated with better clinical outcomes in PDAC, and its downregulation paralleled reduced MIAPaCa-2 proliferation and migration and increased Gem sensitivity. Temporal protein-level Gem responses of MIAPaCa-2 versus GemR cell lines (intrinsically GemR PANC-1 and acquired GemR MIA-GR8) implicate adaptive changes in cellular response systems for cell proliferation and drug transport and metabolism, which reduce cytotoxic Gem metabolites, in DNA repair, and additional responses, as key contributors to the complexity of GemR in PDAC. These findings additionally suggest targetable therapeutic vulnerabilities for GemR PDAC patients.

Chemotherapy with gemcitabine for unresectable intrahepatic cholangiocarcinoma in a patient undergoing maintenance hemodialysis

A 56-year-old man with chronic renal failure due to diabetic nephropathy had received maintenance dialysis (every 4 h, three times/week). A hypoechoic tumor measuring 67 × 50 mm in the right lobe of the liver was discovered following routine abdominal ultrasonography. Dynamic computed tomography showed a low-density liver tumor, enlarged hilar lymph node, and a small nodule on the dorsal side of the lower lobe of the left lung. Histopathological examination of the liver tumor revealed intrahepatic cholangiocarcinoma. We developed a chemotherapy treatment plan with gemcitabine, which can be performed concurrently with hemodialysis. Gemcitabine (1000 mg/m², three times/cycle) was administered on Friday afternoon, and hemodialysis was performed on Tuesday, Thursday, and Saturday. Anemia and hypotension occurred after gemcitabine administration. Therefore, the dose of darbepoetin alpha was increased, and packed red blood cells were transfused. The patient was treated with gemcitabine for approximately 5 and a half months until computed tomography findings showed progressive disease; the survival time after treatment start was 8 months. Chemotherapy using gemcitabine has not been established in dialysis patients and has little evidence. We report a case of unresectable intrahepatic cholangiocarcinoma that developed during maintenance dialysis and was treated using gemcitabine chemotherapy.

Safety of adjuvant gemcitabine plus cisplatin chemotherapy in a patient with bilateral ureteral cancer undergoing hemodialysis

An 80 year old Japanese man with bilateral ureteral cancer underwent laparoscopic bilateral nephroureterectomy and lymph-node dissection. The pathological stage of the left and right ureteral tumors was pT3pN0M0. He received two courses of adjuvant gemcitabine and cisplatin chemotherapy while undergoing hemodialysis. The standard dose of gemcitabine and 50% of the standard dose of cisplatin were administered on the same day. Hemodialysis was started 6 h after gemcitabine administration and 1 h after cisplatin administration. The side effects were evaluated according to the Common Terminology Criteria for Adverse Events v4.0. In the first course, Grade 4 side effects including leukopenia, neutropenia, and thrombocytopenia were observed. He was treated with granulocyte colony-stimulating factor and platelet transfusion. Because the second course was administered without reducing the doses, granulocyte colony-stimulating factor was administered prophylactically, and Grade 4 side effects were reduced to Grade 3. Gemcitabine plus cisplatin chemotherapy can be administered safely in a patient with advanced ureteral cancer undergoing hemodialysis by adequately managing adverse events.

Preoperative chemoradiotherapy using gemcitabine for pancreatic ductal adenocarcinoma in patients with impaired renal function

PURPOSE

Preoperative chemoradiotherapy (CRT) can be a promising treatment for pancreatic ductal adenocarcinoma (PDAC). However, its administration for patients with impaired renal function has not been well investigated, let alone its clinical effect. We previously reported preliminary feasibility of CRT in PDAC patients with renal impairment. Herein, we aimed to investigate the clinical effects of preoperative CRT including safety and long-term prognosis in more PDAC patients with renal impairment as an extension to our previous work.

METHODS

This study enrolled twenty patients harboring resectable PDAC with creatinine clearance level less than 60 ml/min. Patients underwent preoperative CRT with gemcitabine, followed by surgery. The clinical effects of the therapy were evaluated in terms of safety and long-term prognosis.

RESULTS

Preoperative CRT was completed in all 20 patients. Grade 4 leukopenia/neutropenia was identified as an observed toxicity in four cases (20.0%). Renal function was not worsened after CRT. After CRT, 17 cases were judged resectable and underwent laparotomy. Pancreatic resection was performed in 15 of the 17 patients; it was not performed in two patients because of peritoneal dissemination. The 1-/3-/5-year cumulative survival rate from the initiation of CRT for the 20 patients was 88.8%/45.5%/22.8%. In the 15 patients, renal function was not worsened after surgery.

CONCLUSION

Our findings suggest that the clinical effects of preoperative CRT would be favorable in PDAC patients with renal impairment.

Management of patients with end-stage renal disease undergoing chemotherapy: recommendations of the Associazione Italiana di Oncologia Medica (AIOM) and the Società Italiana di Nefrologia (SIN)

Background

The overall risk of some cancers is increased in patients receiving regular dialysis treatment due to chronic oxidative stress, a weakened immune system and enhanced genomic damage. These patients could benefit from the same antineoplastic treatment delivered to patients with normal renal function, but a better risk/benefit ratio could be achieved by establishing specific guidelines. Key considerations are which chemotherapeutic agent to use, adjustment of dosages and timing of dialysis in relation to the administration of chemotherapy.

Methods

We have reviewed available data present in the literature, including recommendations and expert opinions on cancer risk and use of chemotherapeutic agents in patients with end-stage renal disease. Experts selected by the boards of the societies provided additional information which helped greatly in clarifying some issues on which clear-cut information was missing or available data were conflicting.

Results

Data on the optimal use of chemotherapeutic agents or on credible schemes of polychemotherapy in haemodialysed patients are sparse and mainly derive from case reports or small case series. However, recommendations on dosing and timing of dialysis can be proposed for the most prescribed chemotherapeutic agents.

Discussion

The use of chemotherapeutic agents as single agents, or in combination, can be safely given in patients with end-stage renal disease. Appropriate dosage adjustments should be considered based on drug dialysability and pharmacokinetics. Coordinated care between oncologists, nephrologists and pharmacists is of pivotal importance to optimise drug delivery and timing of dialysis.

Pharmacokinetic/pharmacodynamic considerations for cancer patients undergoing hemodialysis

INTRODUCTION

The increased incidence of cancer in hemodialysis patients has been discussed since the mid-70s. Today, physicians regularly encounter situations where they must manage the prescription of anticancer drugs in hemodialysis patients. Areas covered: Hemodialysis patients are at risk of dose-related toxicities due to pharmacokinetic modifications. Hemodialysis patients are at risk of therapeutic drug removal during their hemodialysis session, which may result in a loss of efficacy. In the advent of novel immunotherapies, particularly tumor vaccines, there is an increased theoretical risk of pharmacodynamic modification. Indeed, pharmacodynamic modifications have already been reported for viral vaccines. Expert opinion: It is important to consider all of the potential pharmacokinetic/pharmacodynamic modifications before prescribing anticancer drugs in hemodialysis patients. However, pharmacokinetic/pharmacodynamic modification should not be considered a contraindication for anticancer drug use in hemodialysis patients, rather, clinicians should be aware of the need individualize treatment according to available recommendations.

A comprehensive survey of the mutagenic impact of common cancer cytotoxics

BACKGROUND

Genomic mutations caused by cytotoxic agents used in cancer chemotherapy may cause secondary malignancies as well as contribute to the evolution of treatment-resistant tumour cells. The stable diploid genome of the chicken DT40 lymphoblast cell line, an established DNA repair model system, is well suited to accurately assay genomic mutations.

RESULTS

We use whole genome sequencing of multiple DT40 clones to determine the mutagenic effect of eight common cytotoxics used for the treatment of millions of patients worldwide. We determine the spontaneous mutagenesis rate at 2.3 × 10(-10) per base per cell division and find that cisplatin, cyclophosphamide and etoposide induce extra base substitutions with distinct spectra. After four cycles of exposure, cisplatin induces 0.8 mutations per Mb, equivalent to the median mutational burden in common leukaemias. Cisplatin-induced mutations, including short insertions and deletions, are mainly located at sites of putative intrastrand crosslinks. We find two of the newly defined cisplatin-specific mutation types as causes of the reversion of BRCA2 mutations in emerging cisplatin-resistant tumours or cell clones. Gemcitabine, 5-fluorouracil, hydroxyurea, doxorubicin and paclitaxel have no measurable mutagenic effect. The cisplatin-induced mutation spectrum shows good correlation with cancer mutation signatures attributed to smoking and other sources of guanine-directed base damage.

CONCLUSION

This study provides support for the use of cell line mutagenesis assays to validate or predict the mutagenic effect of environmental and iatrogenic exposures. Our results suggest genetic reversion due to cisplatin-induced mutations as a distinct mechanism for developing resistance.

Tuning pharmacokinetics and biodistribution of a targeted drug delivery system through incorporation of a passive targeting component

Major challenges in the development of drug delivery systems (DDSs) have been the short half-life, poor bioavailability, insufficient accumulation and penetration of the DDSs into the tumor tissue. Understanding the pharmacokinetic (PK) parameters of the DDS is essential to overcome these challenges. Herein we investigate how surface chemistry affects the PK profile and organ distribution of a gold nanoparticle-based DDS containing both a passive and active targeting moiety via two common routes of administration: intravenous and intraperitoneal injections. Using LC/MS/MS, ELISA and INAA we report the half-life, peak plasma concentrations, area under the curve, ability to cross the peritoneal barrier and biodistribution of the nanoconjugates. The results highlight the design criteria for fine-tuning the PK parameters of a targeted drug delivery system that exploits the benefits of both active and passive targeting.

[Management of chemotherapy in hemodialysis patients]

BACKGROUND

The increased incidence of cancer in dialysis patients has been discussed since the mid-70s. Consequently, oncologists, nephrologists and pharmacists are increasingly facing challenging situations of cytotoxic drug handling in dialysis patients. In dialysis patients, two main issues must be considered. First, renal function of hemodialysis (HD) patients is no longer functional. Therefore, these patients may necessitate drug dosage reduction, namely drug prescription, must be cautiously checked before administration with appropriate dosage adjustment whenever necessary to ensure efficacy while avoiding overdosage and related side effects. Secondly, drug clearance by dialysis must be taken into account for appropriate chemotherapy timing in order to avoid drug removal, which may result in a loss of efficacy.

METHODS

We reviewed the international literature on the pharmacokinetics, efficacy, tolerance and dosage adjustment of anticancer drugs used on hemodialysis cancer patients, using the key words: kidney, renal, dialysis, hemodialysis, end-stage renal disease and the name of each drug.

RESULTS

Only case reports and small series were found. 57.1% of the drugs need dosage adjustment and 64.3% should be administered after the dialysis session.

CONCLUSION

Cancer treatment in feasible in dialysis patients. Some drugs require dosage adaptation while others can be given as in patients with normal kidney function. These patients need coordinated care between oncologists, nephrologists and pharmacists to optimize drug delivery and logistics. Frailty scores, like in oncogeriatrics, should be built to optimally adapt cancer treatments in these dialysis patients.

Proposal for dosage adjustment and timing of chemotherapy in hemodialyzed patients

BACKGROUND

The increased incidence of malignancies in patients with chronic renal failure has been discussed since the mid-70s. On the other hand, the high frequency of chronic renal insufficiency among cancer patients has been recently assessed in the Insuffisance Rénale et Médicaments Anticancéreux Study which demonstrated a prevalence as high as 50%-60% of the patients for all stages of kidney disease. Furthermore, the incidence of end-stage renal disease is growing worldwide and so is the number of patients on chronic dialysis, hemodialysis (HD) for the large majority of them. As a result, the question of cytotoxic drug handling in those patients in terms of dosage adjustment and time of administration regarding the dialysis sessions needs to be addressed to optimize cytotoxic drug therapy in those patients.

METHODS

We reviewed the international literature on the pharmacokinetics, efficacy, tolerance and dosage adjustment of cytotoxic drugs used to treat solid tumor patients and when available, specific literature on HD cancer patients.

RESULTS

From these data, dosing recommendations are given for the most prescribed cytotoxic drugs in clinical practice.

CONCLUSIONS

Dosage adjustments are often necessary in HD cancer patients. These adaptations have to be carefully carried out to optimize drug exposure, ensure efficacy and reduce the risk of side-effects.

Pharmacokinetics of gemcitabine and metabolites in a patient with double-sided nephrectomy: a case report and review of the literature

CASE

A patient with complete renal failure as a result of urothelial cell carcinoma-related nephrectomy of both kidneys received palliative chemotherapy with carboplatin and gemcitabine.

TREATMENT

The patient received gemcitabine at 1,000 mg/m(2) followed by carboplatin at 100 mg. Shortly after, he underwent hemodialysis. The pharmacokinetics of gemcitabine and metabolites in plasma and in peripheral blood mononuclear cells were monitored.

RESULTS

Double-sided nephrectomy and hemodialysis had no influence on gemcitabine pharmacokinetics; however, a high exposure was seen for the main metabolite, difluordeoxyuridine (dFdU) (area under the concentration-time curve, 0-51 hours, 844 microg/ml.hour). During hemodialysis, plasma concentrations of dFdU were reduced by 50%. High concentrations of intracellular phosphorylated metabolites (gemcitabine triphosphate and dFdU triphosphate) were observed: 228 pmol/10(6) cells and 47 pmol/10(6) cells, respectively. The patient tolerated the regimen poorly; adverse events included grade 4 thrombocytopenia.

CONCLUSION

Hemodialysis effectively reduced plasma concentrations of dFdU. Furthermore, high concentrations of intracellular phosphorylated metabolites may be related to double-sided nephrectomy, resulting in poor tolerability of gemcitabine.