ERCC1 and RRM1 as a predictive parameter for non-small cell lung, ovarian or pancreas cancer treated with cisplatin and/or gemcitabine

Defining the mode of action of cisplatin combined with NUC-1031, a phosphoramidate modification of gemcitabine

The combination of gemcitabine with platinum agents is a widely used chemotherapy regimen for a number of tumour types. Gemcitabine plus cisplatin remains the current therapeutic choice for biliary tract cancer. Gemcitabine is associated with multiple cellular drug resistance mechanisms and other limitations and has thereforelined in use. NUC-1031 (Acelarin) is a phosphorylated form of gemcitabine, protected by the addition of a phosphoramidate moiety, developed to circumvent the key limitations and generate high levels of the cytotoxic metabolite, dFdCTP. The rationale for combination of gemcitabine and cisplatin is determined by in vitro cytotoxicity. This, however, does not offer an explanation of how these drugs lead to cell death. In this study we investigate the mechanism of action for NUC-1031 combined with cisplatin as a rationale for treatment. NUC-1031 is metabolised to dFdCTP, detectable up to 72 h post-treatment and incorporated into DNA, to stall the cell cycle and cause DNA damage in biliary tract and ovarian cancer cell lines. In combination with cisplatin, DNA damage was increased and occurred earlier compared to monotherapy. The damage associated with NUC-1031 may be potentiated by a second mechanism, via binding the RRM1 subunit of ribonucleotide reductase and perturbing the nucleotide pools; however, this may be mitigated by increased RRM1 expression. The implication of this was investigated in case studies from a Phase I clinical trial to observe whether baseline RRM1 expression in tumour tissue at time of diagnosis correlates with patient survival.

Genetic polymorphisms as potential pharmacogenetic biomarkers for platinum-based chemotherapy in non-small cell lung cancer

Platinum-based chemotherapy (PBC) is a widely used treatment for various solid tumors, including non-small cell lung cancer (NSCLC). However, its efficacy is often compromised by the emergence of drug resistance in patients. There is growing evidence that genetic variations may influence the susceptibility of NSCLC patients to develop resistance to PBC. Here, we provide a comprehensive overview of the mechanisms underlying platinum drug resistance and highlight the important role that genetic polymorphisms play in this process. This paper discussed the genetic variants that regulate DNA repair, cellular movement, drug transport, metabolic processing, and immune response, with a focus on their effects on response to PBC. The potential applications of these genetic polymorphisms as predictive indicators in clinical practice are explored, as are the challenges associated with their implementation.

Molecular Alterations Associated with DNA Repair in Pancreatic Adenocarcinoma Are Associated with Sites of Recurrence

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest malignancies with a rising incidence. Mutational analysis of PDAC has provided valuable information but has not yet dramatically changed the therapeutic landscape due to the number of variations detected in any one individual. The pattern of molecular alterations-gene mutations, variations in copy number, and changes in gene expression-has been described in the literature. The purpose of this study is to further investigate the molecular alterations in recurrent or metastatic PDAC based on the site of disease.

METHODS

Molecular alterations in patients with recurrent or metastatic PDAC from 2007 to 2015 were analyzed. The most common molecular alterations found in PDAC tumors from the pancreas were compared to metastatic PDAC specimens from the liver, lung, peritoneum, and other locations. Means were compared with a two-tailed Student's t test or ANOVA as appropriate. Rates of molecular alterations among the different groups were compared with Pearson's χ².

RESULTS

Two thousand five hundred fifty-two patients with PDAC were identified in a retrospective database, and the 15 most common molecular alterations were utilized for analysis. The most common alterations among all patients were mutations in KRAS and PTEN (59 and 62%, respectively), with differences in prevalence by site of metastasis (p = 0.042 and p = 0.037, respectively). KRAS mutations were more commonly found in metastasis in the lung (72%) than in other sites (59%, p = 0.042). Low expression of ERCC1 was found in 49% of lung metastases from PDAC but only 15% in PDAC in the pancreas (p < 0.001). Five of the 8 molecular alterations significantly associated with site of metastatic disease were involved in DNA maintenance, repair, replication, or transcription (each p < 0.001).

CONCLUSIONS

Aberrant expression or mutation in genes involved in DNA maintenance is found in association with specific sites of metastatic PDAC. Personalizing therapy for metastatic PDAC based on site of disease and their associated molecular alterations warrants further investigation.

Predictive value of ERCC1, ERCC2, ERCC4, and glutathione S-Transferase Pi expression for the efficacy and safety of FOLFIRINOX in patients with unresectable pancreatic cancer

The platinum-based chemotherapy regimen FOLFIRINOX (leucovorin, fluorouracil, irinotecan, and oxaliplatin) is currently used as a standard treatment for patients with unresectable pancreatic cancer. FOLFIRINOX is associated with severe toxicities, including neutropenia, febrile neutropenia, and anorexia; however, there are currently no reliable biomarkers to predict its efficacy and safety. Several studies of patients with various cancers have shown that tumor expression of excision repair cross-complementing (ERCC) proteins and glutathione S-transferase Pi (GSTPi) correlates with the response to platinum-based chemotherapies. Therefore, in this study, we examined the associations between expression of ERCC proteins and GSTPi and the safety and efficacy of FOLFIRINOX in 34 patients with unresectable pancreatic cancer. ERCC1, ERCC2, ERCC4, and GSTPi expression were examined by immunohistochemical staining of tumor specimens and the results were correlated with overall survival, progression-free survival, response rate, disease control rate, and the frequency of grade 3-4 neutropenia and non-hematologic toxicities. We found that ERCC1, ERCC2, ERCC4, and GSTPi were expressed in tumor samples from 64%, 24%, 18%, and 64% of patients, respectively. Notably, there were no statistically significant associations between the expression pattern of any of the proteins and either the clinical outcomes or the frequency of grade 3-4 neutropenia or grade 3-4 anorexia. Collectively, these data indicate that tumor expression of ERCC1, ERCC2, ERCC4, and GSTPi does not predict the safety or efficacy of FOLFIRINOX in patients with pancreatic cancer.

Overcoming tumor cell chemoresistance using nanoparticles: lysosomes are beneficial for (stearoyl) gemcitabine-incorporated solid lipid nanoparticles

Despite recent advances in targeted therapies and immunotherapies, chemotherapy using cytotoxic agents remains an indispensable modality in cancer treatment. Recently, there has been a growing emphasis in using nanomedicine in cancer chemotherapy, and several nanomedicines have already been used clinically to treat cancers. There is evidence that formulating small molecular cancer chemotherapeutic agents into nanomedicines significantly modifies their pharmacokinetics and often improves their efficacy. Importantly, cancer cells often develop resistance to chemotherapy, and formulating anticancer drugs into nanomedicines also helps overcome chemoresistance. In this review, we briefly describe the different classes of cancer chemotherapeutic agents, their mechanisms of action and resistance, and evidence of overcoming the resistance using nanomedicines. We then emphasize on gemcitabine and our experience in discovering the unique (stearoyl) gemcitabine solid lipid nanoparticles that are effective against tumor cells resistant to gemcitabine and elucidate the underlying mechanisms. It seems that lysosomes, which are an obstacle in the delivery of many drugs, are actually beneficial for our (stearoyl) gemcitabine solid lipid nanoparticles to overcome tumor cell resistance to gemcitabine.

MicroRNA-1468-5p inhibits glioma cell proliferation and induces cell cycle arrest by targeting RRM1

MicroRNAs are associated with different types of cancers. In this study, we found that miR-1468-5p could inhibit growth and cell cycle progression in glioma by targeting ribonucleotide reductase large subunit M1 (RRM1). First, we analyzed miR-1468-5p expression in different glioma grades and the prognostic significance of its expression in glioblastoma multiform patients from the Chinese Glioma Genome Atlas. Then, we expressed miR-1468-5p in U87 and U251 cells and assessed the effects on proliferation and cell cycle progression using cell counting kit-8, colony formation, EdU and flow cytometry assays. Western blotting and luciferase reporter assays identified RRM1 as a novel direct target of miR-1468-5p. Experiments to determine the role of RRM1 in glioma showed that RRM1 expression was significantly higher in glioma than in normal brain tissues, and silencing RRM1 with small-interfering RNAs decreased proliferation and suppressed cell cycle progression, which indicated that RRM1 had pro-tumor functions. miR-1468-5p overexpression suppressed RRM1 expression, reduced glioma cell proliferation and induced cell cycle arrest, which was partially rescued by forced RRM1 expression. In summary, our study revealed that the regulatory mechanism of miR-1468-5p in glioma cell cycle progression involved direct regulation of RRM1 expression, suggesting that RRM1 may be a potential therapeutic target for glioma.

Ginsenoside Rg3 Serves as an Adjuvant Chemotherapeutic Agent and VEGF Inhibitor in the Treatment of Non-Small Cell Lung Cancer: A Meta-Analysis and Systematic Review

Objective. To evaluate ginsenoside Rg3 combined with chemotherapy for non-small-cell lung cancer (NSCLC) treatment, in a meta-analysis. Materials and Methods. We searched PubMed, EMBASE, the Cochrane Library, the China National Knowledge Infrastructure, and the VIP and Wanfang databases for eligible studies. We manually searched for printed journals and relevant textbooks. Statistical analyses were performed with Revman 5.3 and STATA 14.0 software packages. Results. Twenty studies were included. Ginsenoside Rg3 combined with chemotherapy could enhance response, improve disease control, prolong overall survival, improve patient quality of life, reduce leucocyte count decrease due to chemotherapy, reduce vascular endothelial growth factor expression in peripheral blood, and increase CD4/CD8 T cell ratio. Conclusion. Ginsenoside Rg3 combined with chemotherapy may enhance short-term efficacy and overall survival, alleviate treatment-induced side effects, reduce vascular endothelial growth factor expression, increase CD4/CD8 T cell ratio, and serve as a potential therapeutic regimen for NSCLC. However, considering the limitations, the conclusion should be interpreted carefully, and these results need to be confirmed by more high-quality trials.

Genomic alterations in neuroendocrine cancers of the ovary

BACKGROUND

As we have previously reported, small cell carcinoma of the ovary (SCCO) is a rare, aggressive form of ovarian cancer associated with poor outcomes. In an effort to identify new treatment options, we utilized comprehensive genomic profiling to assess the potential for novel therapies in SCCO.

METHODS

Patients with SCCO, SCCO-HT (hypercalcemic type), neuroendocrine tumors of the ovary (NET-O), and small cell carcinoma of the lung (SCLC) profiled by Caris Life Sciences between 2007-2015 were identified. Tumors were assessed with up to 21 IHC stains, in situ hybridization of cMET, EGFR, HER2 and PIK3CA, and next-generation sequencing (NGS) as well as Sanger sequencing of selected genes.

RESULTS

Forty-six patients with SCCO (10 SCCO, 18 SCCO-HT, 18 NET-O) were identified as well as 58 patients with SCLC for comparison. Patients with SCCO and SCCO-HT were younger (median 42 years [range 12-75] and 26 years [range 8-40], respectively) than patients with NET-O 62 [range 13-76] or SCLC 66 [range 36-86]. SCCO patients were more likely to be metastatic (70 %) than SCCO-HT (50 %) or NET-O (33 %) patients, but at a similar rate to SCLC patients (65 %). PD1 expression varied across tumor type with SCCO (100 %), SCCO-HT (60 %), NET-O (33 %) vs SCLC (42 %). PDL1 expression also varied with SCCO (50 %), SCCO-HT (20 %), NET-O (33 %) and SCLC (0 %). No amplifications were identified in cMET, EGFR, or HER2 and only 1 was found in PIK3CA (NET-O). Actionable mutations were rare with 1 patient with SCCO having a BRCA2 mutation and 1 patient with NET-O having a PIK3CA mutation. No other actionable mutations were identified.

CONCLUSIONS

No recurrent actionable mutations or rearrangements were identified using this platform in SCCO. IHC patterns may help guide the use of chemotherapy in these rare tumors.

ERCC1 expression affects outcome in metastatic pancreatic carcinoma treated with FOLFIRINOX: A single institution analysis

INTRODUCTION

No clinically useful predictive factor has been yet identified for treatment of metastatic pancreatic cancer (mPC). It is noteworthy that FOLFIRINOX, despite its high toxicity, is effective only in some patients. We retrospectively analyzed expression of excision repair cross-complementing group-1 (ERCC1) - involved in the repair of platinum induced damage - in patients affected by mPC treated with FOLFIRINOX in order to evaluate its predictive role.

RESULTS

FOLFIRINOX resulted more effective in patients with normal ERCC1 levels than in those with ERCC1 hyper-expression. Median progression free survival (PFS) was 11 vs. 4 months (HR 0.26; 95% CI 0.14-0.50; p<.0001), median overall survival (OS) 16 vs. 8 months (HR 0.23; 95% CI 0.12-0.46; p<.0001) and disease control rate (DCR) 93% vs. 50% (p=0.00006). The advantage was confirmed at univariate and multivariate analysis.

PATIENTS AND METHODS

71 patients with histologically proven mPC and treated with FOLFIRINOX as first-line therapy were considered eligible. mRNA ERCC1 expression was determined using RT-PCR analysis.

DISCUSSION

ERCC1 might be an effective predictor of response to FOLFIRINOX in mPC. Patients overexpressing ERCC1 should be excluded by this often toxic therapy and referred to an alternative treatment.