Rescuing effect of folates on methotrexate cytotoxicity in human trophoblast cells.

OBJECTIVES: Methotrexate (MTX)is a folate antagonist that is administered in several conditions such as rheumatoid arthritis. Its use may associate with adverse effects presumably originating from folate deficiency. Although MTX side effects could be decreased by folate supplementation, the current guideline on folate administration is not precisely established, which could result in irreversible damage especially in high-risk groups like women in childbearing-age. Thus, this study aimed to investigate the in vitro rescuing effect of different folates including folic acid (FA), 5-methyltetrahydrofolate (MTHF) and folinic acid (5-Formyltetrahydrofolic acid, FTHF) on MTX-treated trophoblast cells. METHODS: HTR-8/SVneo cells were stressed with a minimum effective dose of MTX and simultaneously treated with different concentrations of FA, MTHF or FTHF. The rescuing effect was assessed by MTT viability assay. The evaluation was completed by microscopic monitoring, apoptosis assessment and measuring LINE-1 DNA methylation. RESULTS: The MTT viability assay showed no MTX-rescuing effect of FA, but a significant effect of FTHF or MTHF. Microscopic observations supported the results of the viability assay. Accordingly, apoptosis was reduced in MTHF or FTHF treatments, while FA has no effect on the apoptosis induced by MTX. The LINE-1 methylation was not affected by MTX treatment, and not significantly modified in folate supplemented cultures. CONCLUSIONS: Despite the general acceptance of administering FA to prevent adverse events of MTX therapy, our findings suggest that FA may not be optimal, and indicate FTHF or MTHF as a better choice. This study on trophoblast cells suggests that FTHF may be the optimal folate, particularly for women in childbearing-age.

Using zebrafish to assess the effect of chronic, early developmental exposure to environmentally relevant concentrations of 5-fluorouracil and leucovorin.

Environmental contaminants can deleteriously affect aquatic animals. One such contaminant is 5-fluorouracil (5-FU), a long-prescribed chemotherapeutic drug. Leucovorin (LV) is co-administered with 5-FU, potentiating its effects. Zebrafish (Danio rerio) larvae were reared in ng/L treatments of either 5-FU, LV, or a combined 5-FU/LV mixture for 8 dy. Survival was measured daily and swimming behavior assessed every other day. After 8 dy, larval length was measured, and densitometry of p53-labeled cryostat sections determined the extent of apoptosis. No significant differences in survival or apoptosis were found; larvae in the highest concentrations were largest. Changes in behavior of 5-FU-treated larvae were based on exposure duration; changes in LV-treated larvae were affected by drug concentration and duration. Larvae co-exposed to 5-FU/LV had responses like 5-FU-treated larvae. Overall, early developmental exposure of zebrafish larvae to environmentally-relevant concentrations of 5-FU and LV did not adversely affect survival, growth, and behavior suggesting realistic concentrations are sublethal and non-toxic.

FOLFIRI-Mediated Toxicity in Human Aortic Smooth Muscle Cells and Possible Amelioration with Curcumin and Quercetin.

Systemic chemotherapy-mediated cell toxicity is a major risk factor for cardiovascular disease and atherosclerosis. Life-threatening acute events of the FOLFIRI (irinotecan, folinic acid and 5-fluorouracil) regimen are mainly due to DNA damage induced by antimetabolite and topoisomerase inhibition effects. However, the role of human aortic smooth muscle cells (HaVSMCs) in this process and the mechanisms of oxidative stress, DNA and protein damage and apoptosis have not been investigated. Therefore, the effects of curcumin and quercetin on HaVSMC survival in the generation of molecular and cellular toxicity by FOLFIRI treatment and the involvement of vital cellular signalling pathways were investigated. We analysed both FOLFIRI toxicity and the therapeutic potential of quercetin and curcumin in terms of HaVSMC damage using molecular probe and florescence staining, Random Amplified Polymorphic DNA (RAPD), qRT-PCR and Western blot assays. Our study presents two preliminary findings: (a) in HaVSMCs, FOLFIRI treatment significantly induces oxidative damage to both DNA and protein, leading to a dramatic increase in caspase-dependent apoptotic death through P53-mediated Caspase3-dependent mitochondrial apoptosis, and results in TNF-α/Caspase8-mediated necrotic death, and (b) flavonoids not only regulate the expression of genes encoding antioxidant enzymes and increase DNA damage but also limit programmed and necrotic cell death processes in HaVSMCs. Our results clearly indicate the potential for curcumin and, particularly, quercetin as preventative chemotherapeutic interventions for cardiovascular toxicity induced by the FOLFIRI regime in HaVSMCs.

Therapeutic efficacy and toxicity of bolus application of chemotherapy protocol in the treatment of metastatic colorectal cancer.

AIM: To compare efficacy and toxicity of bolus application of chemotherapy protocol, oxaliplatin, fluorouracil (bolus), leucovorin (folfox) between two groups of patients in the therapy of metastatic colorectal carcinoma (mCRC). METHODS: A total of 63 patients were treated for mCRC in the period January 2009 - January 2010 at the Department of Oncology of the Cantonal Hospital Zenica, Bosnia and Herzegovina (first group, 30 patients) and at the Department of Oncology of the Clinical Hospital Centre Bezanijska kosa in Belgrade, Serbia, in the period January 2005 - January 2006 (second group, 33 patients). The patients were treated according the same protocol, i.v. bolus infusion, but in different day intervals (D), 1, 8, 15/28 days or D1-D5/28 days, respectively. In all patients the following factors were analyzed: tumor response, overall survival (OS), progression free survival, hematological and non-hematological toxicity . RESULTS: Colon was the primary localization in almost two thirds of patients. There was no statistically significant difference between the groups according to the age, hematological and non-hematological toxicity, as well as in achieved OS. Progression free survival expressed in months was in average 5 months though with a large range between minimal and maximal survival time. CONCLUSION: Both groups have shown equivalent efficacy to applied chemotherapy protocols. Overall survival in the two groups matched data from the literature. Further research should confirm success of the combination of chemotherapy protocols and their combination with the biological therapy.

Pathogenesis of FOLFOX induced sinusoidal obstruction syndrome in a murine chemotherapy model.

BACKGROUND & AIMS: Sinusoidal obstruction syndrome (SOS) following oxaliplatin based chemotherapy can have a significant impact on post-operative outcome following resection of colorectal liver metastases. To date no relevant experimental models of oxaliplatin induced SOS have been described. The aim of this project was to establish a rodent model which could be utilised to investigate mechanisms underlying SOS to aid the development of therapeutic strategies. METHODS: C57Bl/6 mice, maintained on a purified diet, were treated with intra-peritoneal FOLFOX (n=10), or vehicle (n=10), weekly for five weeks and culled one week following final treatment. Sections of the liver and spleen were fixed in formalin and paraffin embedded for histological analysis. The role of oxidative stress on experimental-induced SOS was determined by dietary supplementation with butylated hydroxyanisole and N-acetylcysteine. RESULTS: FOLFOX treatment was associated with the development of sinusoidal dilatation and hepatocyte atrophy on H&E stained sections of the liver in keeping with SOS. Immunohistochemistry for p21 demonstrated the presence of replicative senescence within the sinusoidal endothelium. FOLFOX induced endothelial damage leads to a pro-thrombotic state within the liver associated with upregulation of PAI-1 (p<0.001), vWF (p<0.01) and Factor X (p<0.001), which may contribute to the propagation of liver injury. Dietary supplementation with the antioxidant BHA prevented the development of significant SOS. CONCLUSIONS: We have developed the first reproducible model of chemotherapy induced SOS that reflects the pathogenesis of this disease in patients. It appears that the use of antioxidants alongside oxaliplatin based chemotherapy may be of value in preventing the development of SOS in patients with colorectal liver metastases.

An experimental study to identify the potential role of pharmacogenomics in determining the occurrence of oxaliplatin-induced liver injury.

BACKGROUND: Oxaliplatin-based chemotherapy has been linked to the development of sinusoidal obstruction syndrome (SOS), which is detrimental to outcome after liver resection for colorectal liver metastases (CLM). The aim of this study was to determine how the expression of genes involved in the transport and metabolism of FOLFOX chemotherapy impacts on tissue injury in a murine model of CLM. METHODS: Experimental CLM was established in C57/B16 mice and treated with FOLFOX chemotherapy. After 3 weeks, the animals were killed and RNA extracted from liver, spleen and tumour tissue. DNA damage was assessed by immunohistochemistry for γH2AX. Gene expression was determined by reverse transcriptase polymerase chain reaction. RESULTS: FOLFOX treatment was associated with an increase in the number of γH2AX-positive cells in both the spleen (P < 0.01) and tumour tissue (P < 0.01), but not the liver. Tissue resistance to injury following FOLFOX was associated with high expression of the copper transporter ATP7B. Differences in the expression of genes related to 5-fluorouracil metabolism or DNA repair did not correlate with the severity of tissue injury. CONCLUSIONS: High levels of expression of ATP7B are associated with resistance to tissue injury following FOLFOX chemotherapy. Polymorphisms in the ATP7B gene may explain varying susceptibility to SOS among patients following oxaliplatin-based chemotherapy.

Refining the UGT1A haplotype associated with irinotecan-induced hematological toxicity in metastatic colorectal cancer patients treated with 5-fluorouracil/irinotecan-based regimens.

Despite the importance of UDP-glucuronosyltransferase (UGT) 1A1*28 in irinotecan pharmacogenetics, our capability to predict drug-induced severe toxicity remains limited. We aimed at identifying novel genetic markers that would improve prediction of irinotecan toxicity and response in advanced colorectal cancer patients treated with folic acid (leucovorin), fluorouracil (5-FU), and irinotecan (camptosar)-based regimens. The relationships between UGT1A candidate markers across the gene (n = 21) and toxicity were prospectively evaluated in 167 patients. We included variants in the 3'untranscribed region (3'UTR) of the UGT1A locus, not studied in this context yet. These genetic markers were further investigated in 250 Italian FOLFIRI-treated patients. Several functional UGT1A variants, including UGT1A1*28, significantly influenced risk of severe hematologic toxicity. As previously reported in the Italian cohort, a 5-marker risk haplotype [haplotype II (HII); UGTs 1A9/1A7/1A1] was associated with severe neutropenia in our cohort [odds ratio (OR) = 2.43; P = 0.004]. The inclusion of a 3'UTR single-nucleotide polymorphism (SNP) permitted refinement of the previously defined HI, in which HIa was associated with the absence of severe neutropenia in combined cohorts (OR = 0.55; P = 0.038). Among all tested UGT1A variations and upon multivariate analyses, no UGT1A1 SNPs remained significant, whereas three SNPs located in the central region of UGT1A were linked to neutropenia grade 3-4. Haplotype analyses of these markers with the 3'UTR SNP allowed the identification of a protective HI (OR = 0.50; P = 0.048) and two risk haplotypes, HII and HIII, characterized by 2 and 3 unfavorable alleles, respectively, revealing a dosage effect (ORs of 2.15 and 5.28; P ≤ 0.030). Our results suggest that specific SNPs in UGT1A, other than UGT1A1*28, may influence irinotecan toxicity and should be considered to refine pharmacogenetic testing.

Effectiveness and safe use of modified FOLFOX-6 for metastatic gastric cancer with signet ring cell components complicated by disseminated intravascular coagulation and diffuse bone marrow carcinomatosis.

We report the case of a 62-year-old woman with a metastatic gastric cancer complicated by diffuse bone marrow carcinomatosis, disseminated intravascular coagulation (DIC) and microangiopathic hemolytic anemia (MHA) treated by modified FOLFOX-6 as front-line chemotherapy regimen. This chemotherapy showed clinical, morphological and biological efficiency and safety in this rare and severe hematological complication at initial diagnosis. Furthermore, this is the first case of diffuse bone carcinomatosis from a gastric cancer to be monitored by positron emission tomography integrated computed tomography (PET-CT) scan using 18-fluorodeoxyglucose (18-FDG).

[Comparison of the toxicities and efficacies of the combination chemotherapy regimens in advanced gastric cancer patients who achieved complete response after chemotherapy].

BACKGROUND/AIMS: We retrospectively analyzed comparative toxicities and efficacies of chemotherapy regimens in advanced gastric cancer (AGC) patients who achieved complete response (CR) after chemotherapy. METHODS: We reviewed the medical records of 1,203 patients, who were pathologically diagnosed as AGC in a single center between January 2001 and October 2007. On the basis of the Response Evaluation Criteria in Solid Tumors, CR was evaluated with abdominal computed tomography. Toxicities were evaluated using the National Cancer Institute's common toxicity criteria before each chemotherapy cycle. RESULTS: Among the 1,203 AGC patients enrolled in this study, 568 received chemotherapy and 635 received best supportive care. The major chemotherapy regimens were 5-fluorouracil, leucovorin and oxaliplatin (FOLFOX), docetaxel, cisplatin and 5-fluorouracil (DCF) and 5-fluorouracil, leucovorin and irinotecan (FOLFIRI). Among the 568 patients, 51 (9.0%) achieved CR (49 [8.6%] with FOLFOX [n=12], DCF [n=26], or FOLFIRI [n=11] and 2 [0.3%] with etoposide, leucovorin and 5-fluorouracil). For patients administered FOLFOX, DCF, and FOLFIRI, the median time to disease progression was 4 months (range, 1.8-59.5), 15 months (range, 2.9-31.2) and 10 months (range, 2.0-39.5), and the median survival times were 48 months (range, 5.9-74.0), 37 months (range, 14.0-86.0), and 30 months (range, 6.0-50.0), respectively. Grades 3-4 mucositis occurred mostly in patients administered DCF (n=8, 30.8%). Grades 3-4 leucopenia were observed in 1 (8.3%), 11 (42.3%), and 4 (36.4%) patients administered FOLFOX, DCF and FOLFIRI, respectively. No statistically significant differences were observed in the 3 regimens. CONCLUSIONS: All 3 regimens (FOLFOX, DCF and FOLFIRI) were active and tolerable. Their efficacies and toxicities were not significantly different.

[Neoadjuvant therapy concepts for liver metastases]. / Neoadjuvante Therapiekonzepte bei Lebermetastasen.

The resection of liver metastases offers the option of long-term survival for patients with colorectal carcinoma. With regard to resectability three clinical situations can be identified: patients with resectable liver metastases, those with potentially resectable liver metastases and patients with disseminated metastatic disease. Patients with potentially resectable liver metastases should be treated with regimens with high response rates. According to a metaanalysis patients with resectable liver metastases have a better disease-free survival with the combination of resection and chemotherapy. If neoadjuvant therapy is planned in resectable patients the FOLFOX regimen is the schedule with the highest level of evidence. In potentially resectable liver metastases the regimens FOLFIRI/cetuximab and FOLFOXIRI have demonstrated higher response and resection rates in phase III trials. During neoadjuvant therapy resectability should be regularly reevaluated. Operations should be planned as soon as resectability is achieved because a longer therapy will increase morbidity and because of uncertainty over the approach to patients with complete remission.