Pharmacogenomics of platinum-based chemotherapy in NSCLC

X-ray cross-complementing family: the bridge linking DNA damage repair and cancer

Genomic instability is a common hallmark of human tumours. As a carrier of genetic information, DNA is constantly threatened by various damaging factors that, if not repaired in time, can affect the transmission of genetic information and lead to cellular carcinogenesis. In response to these threats, cells have evolved a range of DNA damage response mechanisms, including DNA damage repair, to maintain genomic stability. The X-ray repair cross-complementary gene family (XRCC) comprises an important class of DNA damage repair genes that encode proteins that play important roles in DNA single-strand breakage and DNA base damage repair. The dysfunction of the XRCC gene family is associated with the development of various tumours. In the context of tumours, mutations in XRCC and its aberrant expression, result in abnormal DNA damage repair, thus contributing to the malignant progression of tumour cells. In this review, we summarise the significant roles played by XRCC in diverse tumour types. In addition, we discuss the correlation between the XRCC family members and tumour therapeutic sensitivity.

Overweight and Obesity are Associated with Poorer Survival Among Patients with Advanced Non-Small Cell Lung Cancer Receiving Platinum-Based Chemotherapy

Background and Aim

Most patients with non-small cell lung cancer (NSCLC) are diagnosed in advanced-stage disease and therefore have poor overall survival. It remains unclear whether nutritional status affects response rate and overall survival in NSCLC patients. This study aimed to evaluate the association of nutritional status with treatment response and overall survival in patients with advanced stage of NSCLC.

Methods

Patients aged ≥18 years with stage II-IV NSCLC (January-June 2018) in a national cancer center in Indonesia were enrolled in this study. The patients were followed up for 2 years since NSCLC diagnosis was established. Clinical data including age, sex, histology of cancer, disease stage, cachexia, and weight status before chemotherapy were reviewed and analyzed. Logistic regression and Cox regression analyses were performed.

Results

A total of 174 patients (71% males, mean age = 58±9.4 years) was included. Complete response was found in <1% patients, partial response 41%, stable disease 33%, and progressive disease 25%. Median survival was 12 months (95% CI: 11-13 months). Mortality rate was 5.7 per 100 person-months. Poor survival was associated with being males (HR: 1.77, 95% CI: 1.15-2.72, P = 0.009), and overweight or obesity (HR 1.67, 95% CI: 1.04-2.69, P = 0.034). These associations were independent of sex, age, staging, histopathology, performance status and D-dimer level at baseline. Cachexia and BMI at baseline were not associated with treatment response.

Conclusion

Males and having overweight or obesity are independently associated with lower survival in patients with advanced stage of NSCLC undergoing platinum-based chemotherapy.

A Screening of Epigenetic Therapeutic Targets for Non-Small Cell Lung Cancer Reveals PADI4 and KDM6B as Promising Candidates

Despite advances in diagnostic and therapeutic approaches for lung cancer, new therapies targeting metastasis by the specific regulation of cancer genes are needed. In this study, we screened a small library of epigenetic inhibitors in non-small-cell lung cancer (NSCLC) cell lines and evaluated 38 epigenetic targets for their potential role in metastatic NSCLC. The potential candidates were ranked by a streamlined approach using in silico and in vitro experiments based on publicly available databases and evaluated by real-time qPCR target gene expression, cell viability and invasion assays, and transcriptomic analysis. The survival rate of patients with lung adenocarcinoma is inversely correlated with the gene expression of eight epigenetic targets, and a systematic review of the literature confirmed that four of them have already been identified as targets for the treatment of NSCLC. Using nontoxic doses of the remaining inhibitors, KDM6B and PADI4 were identified as potential targets affecting the invasion and migration of metastatic lung cancer cell lines. Transcriptomic analysis of KDM6B and PADI4 treated cells showed altered expression of important genes related to the metastatic process. In conclusion, we showed that KDM6B and PADI4 are promising targets for inhibiting the metastasis of lung adenocarcinoma cancer cells.

How platinum-induced nephrotoxicity occurs? Machine learning prediction in non-small cell lung cancer patients

BACKGROUND AND OBJECTIVE

Platinum-induced nephrotoxicity is a severe and unexpected adverse drug reaction that could lead to treatment failure in non-small cell lung cancer patients. Better prediction and management of this nephrotoxicity can increase patient survival. Our study aimed to build up and compare the best machine learning models with clinical and genomic features to predict platinum-induced nephrotoxicity in non-small cell lung cancer patients.

METHODS

Clinical and genomic data of patients undergoing platinum chemotherapy at Wan Fang Hospital were collected after they were recruited. Twelve models were established by artificial neural network, logistic regression, random forest, and support vector machine with integrated, clinical, and genomic modes. Grid search and genetic algorithm were applied to construct the fine-tuned model with the best combination of predictive hyperparameters and features. Accuracy, precision, recall, F1 score, and area under the receiver operating characteristic curve were calculated to compare the performance of the 12 models.

RESULTS

In total, 118 patients were recruited for this study, among which 28 (23.73%) were experiencing nephrotoxicity. Machine learning models with clinical and genomic features achieved better prediction performances than clinical or genomic features alone. Artificial neural network with clinical and genomic features demonstrated the best predictive outcomes among all 12 models. The average accuracy, precision, recall, F1 score and area under the receiver operating characteristic curve of the artificial neural network with integrated mode were 0.923, 0.950, 0.713, 0.808 and 0.900, respectively.

CONCLUSIONS

Machine learning models with clinical and genomic features can be a preliminary tool for oncologists to predict platinum-induced nephrotoxicity and provide preventive strategies in advance.

State of the Art and Future Implications of SH003: Acting as a Therapeutic Anticancer Agent

Cancer ranks as the first leading cause of death globally. Despite the various types of cancer treatments, negative aspects of the treatments, such as side effects and drug resistance, have been a continuous dilemma for patients. Thus, natural compounds and herbal medicines have earned profound interest as chemopreventive agents for reducing burden for patients. SH003, a novel herbal medicine containing Astragalus membranaceus, Angelica gigas, and Trichosanthes kirilowii, showed the potential to act as an anticancer agent in previous research studies. A narrative review was conducted to present the significant highlights of the total 15 SH003 studies from the past nine years. SH003 has shown positive results in both in vivo and vitro studies against various types of cancer cells; furthermore, the first clinical trial was performed to identify the maximum tolerated dose among solid cancer patients. So far, the potential of SH003 as a chemotherapeutic agent has been well-documented in research studies; continuous work on SH003's efficacy and safety is required to facilitate better cancer patient care but is part of the knowledge needed to understand whether SH003 has the potential to become a pharmaceutical.

Synergistic Antitumor Activity of SH003 and Docetaxel via EGFR Signaling Inhibition in Non-Small Cell Lung Cancer

Epidermal growth factor receptor (EGFR) is overexpressed in lung cancer patients. Despite treatment with various EGFR tyrosine kinase inhibitors, recurrence and metastasis of lung cancer are inevitable. Docetaxel (DTX) is an effective conventional drug that is used to treat various cancers. Several researchers have studied the use of traditional herbal medicine in combination with docetaxel, to improve lung cancer treatment. SH003, a novel herbal mixture, exerts anticancer effects in different cancer cell types. Here, we aimed to investigate the apoptotic and anticancer effects of SH003 in combination with DTX, in human non-small-cell lung cancer (NSCLC). SH003, with DTX, induced apoptotic cell death, with increased expression of cleaved caspases and cleaved poly (ADP-ribose) polymerase in NSCLC cells. Moreover, SH003 and DTX induced the apoptosis of H460 cells via the suppression of the EGFR and signal transducer and activator of transcription 3 (STAT3) signaling pathways. In H460 tumor xenograft models, the administration of SH003 or docetaxel alone diminished tumor growth, and their combination effectively killed cancer cells, with increased expression of apoptotic markers and decreased expression of p-EGFR and p-STAT3. Collectively, the combination of SH003 and DTX may be a novel anticancer strategy to overcome the challenges that are associated with conventional lung cancer therapy.

Characterization of a RAD51C-silenced high-grade serous ovarian cancer model during development of PARP inhibitor resistance

Acquired PARP inhibitor (PARPi) resistance in BRCA1- or BRCA2-mutant ovarian cancer often results from secondary mutations that restore expression of functional protein. RAD51C is a less commonly studied ovarian cancer susceptibility gene whose promoter is sometimes methylated, leading to homologous recombination (HR) deficiency and PARPi sensitivity. For this study, the PARPi-sensitive patient-derived ovarian cancer xenograft PH039, which lacks HR gene mutations but harbors RAD51C promoter methylation, was selected for PARPi resistance by cyclical niraparib treatment in vivo. PH039 acquired PARPi resistance by the third treatment cycle and grew through subsequent treatment with either niraparib or rucaparib. Transcriptional profiling throughout the course of resistance development showed widespread pathway level changes along with a marked increase in RAD51C mRNA, which reflected loss of RAD51C promoter methylation. Analysis of ovarian cancer samples from the ARIEL2 Part 1 clinical trial of rucaparib monotherapy likewise indicated an association between loss of RAD51C methylation prior to on-study biopsy and limited response. Interestingly, the PARPi resistant PH039 model remained platinum sensitive. Collectively, these results not only indicate that PARPi treatment pressure can reverse RAD51C methylation and restore RAD51C expression, but also provide a model for studying the clinical observation that PARPi and platinum sensitivity are sometimes dissociated.

The influence of genetic polymorphisms on the toxicity of platinum-based chemotherapy in the treatment of non-small cell lung cancer

Lung cancer remains one of the most frequent and the deadliest of malignant diseases throughout the world. Target and immune therapy have revolutionalized the treatment of this disease, but platinum-based chemotherapy still has a place in the treatment algorithm. The toxicity profile of cisplatin is well known and can be a limiting factor in the adequate treatment delivery of the drug. There are important inter-individual differences in the efficacy and the toxicity of all chemotherapy drugs, which cannot be explained solely by the characteristics of the tumor. In order to define predictive factors for the occurrence of toxic effects, numerous genetic alterations have been investigated - especially single nucleotide polymorphisms (SNPs). The investigated genes are those involved in DNA repair mechanisms, signal pathways of apoptosis, DNA synthesis, transport mechanisms, but often with inconclusive and opposing results. It is clear that the effect of SNPs on the occurrence of cisplatin toxicity cannot be explained by investigating just one or several genes alone, but epigenetic interactions must be investigated, as well as interactions with outside factors. The study of SNPs is, however, a relatively simple and inexpensive method and, as such, can be used as one of the prognostic tools for everyday practice.

Impact of genetic factors on platinum-induced gastrointestinal toxicity

Severe gastrointestinal (GI) toxicity is a common side effect after platinum-based chemotherapy. The incidence and severity of GI toxicity vary among patients with the same chemotherapy. Genetic factors involved in platinum transport, metabolism, detoxification, DNA repair, cell cycle control, and apoptosis pathways may account for the interindividual difference in GI toxicity. The influence of gene polymorphisms in the platinum pathway on GI toxicity has been extensively analyzed. Variations in study sample size, ethnicity, design, treatment schedule, dosing, endpoint definition, and assessment of toxicity make it difficult to precisely interpret the results. Hence, we conducted a review to summarize the most recent pharmacogenomics studies of GI toxicity in platinum-based chemotherapy and identify the most promising avenues for further research.

Clinical Research on Systemic Chemotherapy Combined With Bronchoscopic Seed Implantation in the Treatment of Advanced Lung Cancer

Objective:

This study aims to explore the clinical value of systemic chemotherapy combined with bronchoscopic seed implantation in advanced lung cancer treatment.

Methods:

The study enrolled 253 patients with advanced lung cancer in Cangzhou People’s Hospital from March 2018 to March 2020, and they were divided into test group and control group. Test group was given systemic chemotherapy combined with bronchoscopic seed implantation, while control group was given systemic chemotherapy. The objective response rate of tumor (ORR), disease control rate (DCR), serum tumor marker level, survival time and adverse reactions of 2 groups were compared.

Results:

After treatment, the levels of serum tumor markers including carcino-embryonic antigen, neuro-specific enolase, cytokeratin-19 and pro-gastrin-releasing peptide were markedly decreased in test group compared with those in control group (P < 0.05). Therein, the serum tumor marker level of non-small cell lung cancer (NSCLC) patients was significant decreased compared with that of small cell lung cancer (SCLC) patients in test group. Meanwhile, in test group, the serum tumor marker level of lung adenocarcinoma (LUAD) patients was significant decreased compared with that of lung squamous cell carcinoma (LUSC, P < 0.05). The ORR and DCR in test group were superior to those in control group (63.4%, 92.5% vs 38.7%, 72.3%, P < 0.05), while those were much higher in patients with NSCLC and LUAD relative to those in patients with SCLC and LUSC, respectively (P < 0.05). Furthermore, the progression-free survival (PFS) and overall survival (OS) in test group were significantly greater than those in control group. In test group, the PFS and OS of patients with NSCLC and LUAD were higher than those of patients with SCLC and LUSC.

Conclusion:

The efficacy of systemic chemotherapy combined with bronchoscopic seed implantation was superior to that of systemic chemotherapy, which is worthy of promoting in clinical practice.

A review on RNAi therapy for NSCLC: Opportunities and challenges

Non-small cell lung cancer (NSCLC) is the primary cause of cancer death worldwide. Despite developments in chemotherapy and targeted therapies, the 5-year survival rate has remained at approximately 16% for the last four decades. NSCLC is a heterogeneous group of tumors that, through mutations and drivers, also demonstrate intra-tumor heterogeneity. Thus, current treatment approaches revolve around targeting these oncogenes, often using small molecule inhibitors and chemotherapeutics. However, the efficacy of these therapies has been crippled by acquired and inherent drug-resistance in the tumor, accompanied by increased therapeutic dosages and subsequent devastating off-target effects for patients. Evidently, there is a critical need for developing treatment methodologies more effective than the current standard of care. Fortunately, RNA interference, particularly small interfering RNA (siRNA), presents an alternative of silencing specific oncogenes to control tumor growth. Although siRNA therapy is subject to rapid degradation and poor internalization in vivo, nanoparticles can serve as nontoxic and efficient delivery vehicles, even introducing combinational delivery of multiple therapeutic agents. Indeed, siRNA-nanoconstructs possess extraordinary potential as an innovative modality to address clinical needs. This state-of-the-art review summarizes the recent advancements in the development of novel nanosystems for delivering siRNA to NSCLC tumors and analyzes the efficacy of representative examples. By illuminating the most promising biomarkers for silencing, we hope to streamline current therapeutic efforts and highlight powerful translational opportunities to combat NSCLC. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Biology-Inspired Nanomaterials > Lipid-Based Structures Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

ERCC1 expression and platinum chemosensitivity in patients with ovarian cancer: A meta-analysis

OBJECTIVE

This study aimed to comprehensively investigate the correlation of ERCC1 expression and chemosensitivity of ovarian cancer.

METHODS

The literature on the relationship between the excision repair cross complementary gene 1 (ERCC1) and the chemosensitivity of ovarian cancer published in PubMed, Web of Science, EMBASE, CNKI, and the China Wanfang database from the establishment of the databases to June 2020 were searched. Chemosensitivity is evaluated by clinical effective rate (complete remission plus partial remission). Statistical analysis was carried out by using Stata 15.1 software.

RESULTS

A total of 11 articles met the inclusion criteria, consisting of 758 patients with ovarian cancer. The results showed a significant difference in chemosensitivity between the low expression group and the high expression group of ERCC1 (odds ratio 4.23; 95% confidence interval 2.96, 6.06; P < 0. 01). The same result was shown in the ethnicity subgroup.

CONCLUSION

The chemosensitivity of ovarian cancer patients with a low expression of ERCC1 is better than that of patients with a high expression.

LncRNA FOXD3-AS1 promoted chemo-resistance of NSCLC cells via directly acting on miR-127-3p/MDM2 axis

Background

This study aims to investigate the mechanism underlying the high level of long non-coding RNA FOXD3-AS1 in cisplatin-resistant NSCLC cells.

Methods

Cisplatin-resistant cells were generated from A549 cells. CCK-8 were used to evaluate cell proliferation. The FOXD3-AS1, miR-127-3p, MDM2 and MRP1 mRNA expression levels were confirmed by qRT-PCR. Protein levels of MDM2 and MRP1 were determined by western blot assay. Luciferase reporter and RNA pull-down assays were evaluated the relationship between miR-127-3p and FOXD3-AS1/MDM2. In vivo tumor growth was evaluated in a xenograft nude mice model.

Results

FOXD3-AS1 was up-regulated in cisplatin-resistant NSCLC cells (A549/DDP and H1299/DDP cells) in comparison with their parental cell lines. Overexpression of FOXD3-AS1 promoted cisplatin-resistance in A549 and H1299 cells; while FOXD3-AS1 knockdown sensitized A549/DDP and H1299/DDP cells to cisplatin treatment. FOXD3-AS1 regulated miR-127-3p expression by acting as a competing endogenous RNA, and miR-127-3p repressed MDM2 expression via targeting the 3'UTR. MiR-127-3p overexpression and MDM2 knockdown both increased the chemo-sensitivity in A549/DDP cells; while miR-127-3p knockdown and MDM2 overexpression both promoted chemoresistance in A549 cells. Further rescue experiments revealed that miR-127-3p knockdown or MDM2 overexpression counteracted the suppressive effects of FOXD3-AS1 knockdown on chemo-resistance and MRP1 expression in A549/DDP cells. In vivo studies showed that FOXD3-AS1 knockdown potentiated the antitumor effects of cisplatin treatment. Inspection of clinical samples showed the upregulation of FOXD3-AS1 and MDM2, and down-regulation of miR-127-3p in NSCLC tissues compared to normal adjacent tissues.

Conclusion

In conclusion, our results suggest that LncRNA FOXD3-AS1 promotes chemo-resistance of NSCLC cells via directly acting on miR-127-3p/MDM2 axis. Our findings may provide novel perspectives for the treatment of NSCLC in patients resistant to chemotherapy.

Targeting KRAS Mutant Non-Small-Cell Lung Cancer: Past, Present and Future

Lung cancer is the most frequent cancer with an aggressive clinical course and high mortality rates. Most cases are diagnosed at advanced stages when treatment options are limited and the efficacy of chemotherapy is poor. The disease has a complex and heterogeneous background with non-small-cell lung cancer (NSCLC) accounting for 85% of patients and lung adenocarcinoma being the most common histological subtype. Almost 30% of adenocarcinomas of the lung are driven by an activating Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation. The ability to inhibit the oncogenic KRAS has been the holy grail of cancer research and the search for inhibitors is immensely ongoing as KRAS-mutated tumors are among the most aggressive and refractory to treatment. Therapeutic strategies tailored for KRAS+ NSCLC rely on the blockage of KRAS functional output, cellular dependencies, metabolic features, KRAS membrane associations, direct targeting of KRAS and immunotherapy. In this review, we provide an update on the most recent advances in anti-KRAS therapy for lung tumors with mechanistic insights into biological diversity and potential clinical implications.

Comparative clinical study on microwave ablation combined with gemcitabine and cisplatin or combined with pemetrexed and cisplatin in treatment of advanced NSCLC

OBJECTIVE

Solving the limitations of single chemotherapy in the treatment of non-small cell lung cancer (NSCLC).

METHODS

About 100 patients with NSCLC treated in First Hospital of Jiaxing, Zhejiang from June 2016 to June 2018 were selected and randomly divided into MPC group and MGC group, with 50 cases in each group. The patients in MPC group were treated with microwave ablation (MWA) combined with PC while patients in MGC group were given MWA combined with gemcitabine plus cisplatin (GC). The therapeutic effects of the two groups as well as the complications and adverse reactions (ADRs) were observed and recorded.

RESULTS

There was no significant difference in disease response rate (MPC group 33.3% vs MGC group 32.0%), disease control rate (MPC group 86.4% vs MGC group 78.0%) and overall survival (1-, 2- and 3-year survival, MPC group 65%, 59%, 32.7% vs MGC group 58%, 46%, 30%) between the two groups. In addition, the ADR myelosuppression was slighter in MPC group. There were 12 cases (23%) developed myelosuppression in the MPC group and 20 cases (42%) in MGC group, with a significant difference between the two groups (P < 0.05). The treatment was interrupted for 0 case (0%) in MPC group because of myelosuppression while 4 cases (8.3%) in MGC group.

CONCLUSION

The two therapeutic regimens have similar efficacy in treatment of advanced NSCLC, but MPC causes slighter myelosuppression and can be the first-line therapy for advanced NSCLC.

MicroRNA-103a-3p potentiates chemoresistance to cisplatin in non-small cell lung carcinoma by targeting neurofibromatosis 1

Lung cancer remains the leading cause of cancer-associated mortality worldwide, and non-small-cell lung cancer (NSCLC) contributes to ~80% of these deaths. However, both primary and acquired cisplatin resistance frequently occurs within the disease and represents a huge clinical treatment problem. The underlying molecular mechanisms are not yet completely understood, but in recent years, microRNAs (miR) have been reported to play vital roles in the development of lung cancer and chemoresistance. In the present study, it was revealed that there were increased expression levels of miR-103a-3p in both NSCLC cell lines and human NSCLC samples that exhibited resistance to cisplatin. The results also revealed that the inhibition of miR-103a-3p in A549/cisplatin cells significantly sensitized these cells to cisplatin, while inhibition of miR-103a-3p expression inhibited tumor growth and enhanced the function of cisplatin in a xenograft animal model. Furthermore, the present study demonstrated that miR-103a-3p regulates cisplatin resistance by targeting neurofibromatosis 1 (NF1) via activating ERK signaling in vitro and in vivo. In conclusion, NF1 was identified as a special miR-103a-3p target in the present study, and it was revealed that targeting NF1 via miR-103a-3p may help reverse chemoresistance and provide a biomarker to cisplatin responsiveness in NSCLC.

Pathogenesis of platinum-induced peripheral neurotoxicity: Insights from preclinical studies

One of the most relevant dose-limiting adverse effects of platinum drugs is the development of a sensory peripheral neuropathy that highly impairs the patients' quality of life. Nowadays there are no available efficacy strategies for the treatment of platinum-induced peripheral neurotoxicity (PIPN), and the only way to prevent its development and progression is by reducing the dose of the cytostatic drug or even withdrawing the chemotherapy regimen. This clinical issue has been the main focus of hundreds of preclinical research works during recent decades. As a consequence, dozens of in vitro and in vivo models of PIPN have been developed to elucidate the molecular mechanisms involved in its development and to find neuroprotective targets. The apoptosis of peripheral neurons has been identified as the main mechanism involved in PIPN pathogenesis. This mechanism of DRG sensory neurons cell death is triggered by the nuclear and mitochondrial DNA platination together with the increase of the oxidative cellular status induced by the depletion of cytoplasmic antioxidant mechanisms. However, since there has been no successful transfer of preclinical results to clinical practise in terms of therapeutic approaches, some mechanisms of PIPN pathogenesis still remain to be elucidated. This review is focused on the pathogenic mechanisms underlying PIPN described up to now, provided by the critical analysis of in vitro and in vivo models.

CLEC4M is associated with poor prognosis and promotes cisplatin resistance in NSCLC patients

Cisplatin-based chemotherapy is the foundation of treatment for major non-small cell lung cancer (NSCLC) patients. However, cisplatin resistance is still a challenging issue, and the molecular mechanisms underlying this resistance remain to be fully explored. CLEC4M, a Ca²⁺-dependent C-type lectin, has recently been found to correlate with tumourigenesis. This study mainly focused on whether CLEC4M impacts clinical prognosis and how CLEC4M contributes to cisplatin resistance in NSCLC. Our results found that CLEC4M was correlated with poor prognosis in patients with lung cancer. In addition, a positive association between CLEC4M expression and the IC50 values of cisplatin was found, which suggests that CLEC4M may impact cisplatin sensitivity. In vitro results from cultured A549 and H1299 cells confirmed that CLEC4M could enhance cisplatin resistance, while CLEC4M knockdown led to higher sensitivity to cisplatin in these cells. Further experiments showed that the underlying mechanisms included inhibition of cisplatin-induced cell apoptosis by CLEC4M and improved DNA repair capacity by upregulating XPA and ERCC1 expression. In addition, CLEC4M was able to promote cell migration with or without cisplatin treatment. Collectively, these findings suggest the potential clinical significance of CLEC4M inhibition in overcoming cisplatin resistance in NSCLC patients.

Genomic profiling in advanced stage non-small-cell lung cancer patients with platinum-based chemotherapy identifies germline variants with prognostic value in SMYD2

OBJECTIVE

The aim of the study was to investigate the relationship between germline variations as a prognosis biomarker in patients with advanced Non-Small-Cell-Lung-Cancer (NSCLC) subjected to first-line platinum-based treatment.

MATERIALS AND METHODS

We carried out a two-stage genome-wide-association study in non-small-cell lung cancer patients with platinum-based chemotherapy in an exploratory sample of 181 NSCLC patients from Caucasian origin, followed by a validation on 356 NSCLC patients from the same ancestry (Valencia, Spain).

RESULTS

We identified germline variants in SMYD2 as a prognostic factor for survival in patients with advanced NSCLC receiving chemotherapy. SMYD2 alleles are associated to a decreased overall survival and with a reduced Time to Progression. In addition, enrichment pathway analysis identified 361 variants in 40 genes to be involved in poorer outcome in advanced-stage NSCLC patients.

CONCLUSION

Germline SMYD2 alleles are associated with bad clinical outcome of first-line platinum-based treatment in advanced NSCLC patients. This result supports the role of SMYD2 in the carcinogenic process, and might be used as prognostic signature directing patient stratification and the choice of therapy.

MICROABSTRACT

A two-Stage Genome wide association study in Caucasian population reveals germline genetic variation in SMYD2 associated to progression disease in first-line platinum-based treatment in advanced NSCLC patients. SMYD2 profiling might have prognostic / predictive value directing choice of therapy and enlighten current knowledge on pathways involved in human carcinogenesis as well in resistance to chemotherapy.

Pharmacogenomics of platinum-based chemotherapy response in NSCLC: a genotyping study and a pooled analysis

Published data showed inconsistent results about associations of extensively studied polymorphisms with platinum-based chemotherapy response. Our study aimed to provide reliable conclusions of these associations by detecting genotypes of the SNPs in a larger sample size and summarizing a comprehensive pooled analysis. 13 SNPs in 8 genes were genotyped in 1024 NSCLC patients by SequenomMassARRAY. 39 published studies and our study were included in meta-analysis. Patients with GA or GG genotypes of XRCC1 G1196 had better response than AA genotype carriers (Genotyping study: OR = 0.72, 95%CI: 0.53-0.96, P = 0.028; Meta-analysis: OR = 0.74, 95%CI: 0.62-0.89, P = 0.001). Patients carrying CT or TT genotypes of XRCC1 C580T could be more sensitive to platinum-based chemotherapy compared to patients with CC genotype (OR = 0.54, 95%CI: 0.37-0.80, P = 0.002). CC genotype of XRCC3 C18067T carriers showed more resistance to platinum-based chemotherapy when compared to those with CT or TT genotypes (OR = 0.69, 95%CI: 0.52-0.91, P = 0.009). Our study indicated that XRCC1 G1196A/C580T and XRCC3 C18067T should be paid attention for personalized platinum-based chemotherapy in NSCLC patients.

Pharmacogenetics of platinum-based chemotherapy in non-small cell lung cancer: predictive validity of polymorphisms of ERCC1

INTRODUCTION

The efficacy of platinum-based chemotherapy for patients with non-small cell lung cancer (NSCLC) is limited by chemoresistance. Platinum drugs damage DNA by introducing intrastrand and interstrand crosslinks which result in cell death. Excision repair cross-complementing 1 (ERCC1) is a member of the nucleotide excision repair (NER) pathway which erases such defects. Single nucleotide polymorphisms (SNPs) in ERCC1 impair this activity and have been suggested to predict the response to chemotherapy. Area covered: Among the polymorphisms of proteins involved in uptake, metabolism, cytotoxicity and efflux of platinum drugs, codon 118 C/T and C8092A in ERCC1 are the best characterized SNPs studied for their predictive power. Here, the divergent results for studies of these markers in NSCLC are summarized and the reasons for this contradictory data discussed. Expert opinion: Cytotoxicity of platinum compounds comprise complex cellular processes for which DNA repair may not constitute the rate limiting step. These drugs are administered as doublets to histologically diverse patients and, furthermore, the NER pathway in ERCC1 wildtype cohorts may be still impaired by the chemotherapeutics applied. At present, assessment of a limited number of polymorphism in DNA repair proteins is not reliably associated with response to treatment in NSCLC patients.

Metformin partially reverses the carboplatin-resistance in NSCLC by inhibiting glucose metabolism

Platinum-based chemotherapeutic drugs are irreplaceable for the treatment of advanced non-small cell lung cancer (NSCLC). However, acquired drug resistance has become a major obstacle for the clinical application of chemotherapy on NSCLC. In the present study, we established carboplatin-resistant NSCLC models on A549 and PC9 cell lines, which were named A549/R and PC9/R. Besides the low sensitivity of A549/R and PC9/R to carboplatin treatment, they exhibited higher metabolism rate of glucose compared to their parental A549 and PC9 cells, respectively. Mechanically, we confirmed that overexpression of PKM2 in A549/R and PC9/R was responsible for the high glucose metabolism and carboplatin resistance. Metformin, an antidiabetic drug, was observed to increase the sensitivity of carboplatin-resistant NSCLC cells to carboplatin treatment in vitro and in vivo. Mechanically, metformin decreased expression of PKM2 and subsequently inhibited the glucose uptake, lactate generation and ATP production in A549/R and PC9/R. Therefore, metformin promoted carboplatin-induced apoptosis through the mitochondria pathway. In addition, we demonstrated that metformin treatment also impaired the cross-resistance of A549/R and PC9/R to cisplatin, etoposide and 5-fluorouracil.

CYP2A6 Polymorphisms Associate with Outcomes of S-1 Plus Oxaliplatin Chemotherapy in Chinese Gastric Cancer Patients

Gastric carcinoma is a heterogeneous malignant disease involving genetic factors. To identify predictive markers for gastric cancer treatment in Chinese patients, we evaluated the association between polymorphisms of the gene encoding cytochrome P450 2A6 (CYP2A6) and outcomes of S-1 plus oxaliplatin (SOX) chemotherapy treatment. Clinical data on 60 consecutive gastric cancer patients receiving SOX regimen were collected prospectively. We sequenced all exons of CYP2A6 and a total of 22 different polymorphisms were detected in the present study. Comprehensive analyses of these genetic polymorphisms were performed to determine their association with both safety and efficacy of SOX regimen. Our results showed that polymorphisms of CYP2A6 were associated with the safety and efficacy of SOX treatment. Among them, missense mutations CYP2A6 rs60823196 and rs138978736 could be possible risk factors (P < 0.05) for severe diarrhea induced by SOX, whereas CYP2A6 rs138978736 could be a conceivable predictor for overall survival of patients treated with SOX adjuvant chemotherapy. Further large-scale randomized prospective studies are warranted to confirm these findings.

Pharmacogenomics of platinum-based chemotherapy in non-small cell lung cancer: focusing on DNA repair systems

Drug therapy for non-small cell lung cancer consists mainly of platinum-based chemotherapy regimens. However, toxicity, drug resistance, and high risk of death have been seen in the clinic, which means there is a need for optimizing the use of medications. Platinum resistance could be mediated by a series of DNA repair pathways, and therefore, these pathways should be taken into account for optimizing drug using. The goal of pharmacogenomics is to elucidate genetic factors, such as DNA repair genes, which might underlie drug efficacy and effectiveness, and to improve therapeutic effects or guide personalized therapy as well. Here, we reviewed the current knowledge of pharmacogenomic data on DNA repair systems and examined whether they could be further translated into the clinic with evidence-based perspectives.

Base excision repair pathway: PARP1 genotypes as modulators of therapy response in cervical cancer patients

CONTEXT

Genetic polymorphisms in genes of the base excision repair (BER) pathway appear to modulate the therapy response of cancer patients. PARP1 protein recognizes the DNA strand damage and facilitates the subsequent recruitment of BER proteins. Few studies have reported an association between PARP1 Val762Ala polymorphism (rs1136410) and cancer therapy response.

OBJECTIVE

The purpose of our study was to determine whether PARP1 Val762Ala polymorphism have prognostic value in patients with cervical cancer.

MATERIALS AND METHODS

Two hundred and sixty adult patients, with histologically confirmed cervical cancer, at FIGO-stages IB2-IVA, primarily treated with concurrent chemotherapy (cisplatin) and radiotherapy. Overall survival (OS) and disease-free survival (DFS) were the primary end points of the analysis. The PARP1 Val762Ala genetic variants were analyzed by allelic discrimination by real-time PCR.

RESULTS

We observed that peri- and postmenopausal women carrying the C-allele present a statistically significant lower OS and DFS (log-rank test, p = 0.008 and p = 0.006, respectively) among those with early stage cervical cancer. Cox regression analysis confirmed these results, after adjustment for other prognostic factors (for OS: HR, 3.70; 95%CI, 1.32-10.38; p = 0.013 and for DFS: HR, 3.97; 95%CI, 1.59-9.93; p = 0.003).

CONCLUSIONS

This is the first study evaluating the effect of PARP1 Val762Ala polymorphism in treatment response in cervical cancer patients. PARP1 genotypes may contribute as an independent prognostic factor in cervical cancer, being useful in predicting the clinical outcome.

Expression of the copper transporters hCtr1, ATP7A and ATP7B is associated with the response to chemotherapy and survival time in patients with resected non-small cell lung cancer

Copper transporter family proteins may regulate the chemoresistance of non-small cell lung cancer (NSCLC) to platinum-based anticancer drugs. The present study aimed to investigate the expression of these proteins in lung cancer tissue specimens for association with clinicopathological data and patient responses to chemotherapy and survival. A total of 54 patients with surgically resected NSCLC that received first-line platinum-based doublet chemotherapy were recruited in the present study, and the paraffin-embedded pre-treatment tumor tissue specimens were subjected to immunohistochemical analysis for the expression of human copper transporter 1 (hCtr1) and copper-transporting p-type adenosine triphosphatase 1 (ATP7A) and 2 (ATP7B). This cohort of patients with NSCLC received platinum-based chemotherapy subsequent to the surgical removal of tumor lesions. ATP7B expression was found to be significantly associated with tumor cell differentiation, while hCtr1 expression was significantly associated with improved chemotherapeutic responses. The median survival time was 20 months in patients possessing tumors with high ATP7A expression, but >66 months in patients possessing tumors with low ATP7A expression at the end of the follow-up (P<0.001). The median survival time at the end of the follow-up was 15 months in patients with low tumor hCtr1 expression, but >66 months in patients with high tumor hCtr1 expression (P<0.001). High hCtr1 and low ATP7A expression were each favorable prognostic factors subsequent to chemotherapy for patients with resected NSCLC. Multivariate analysis revealed that high hCtr1 expression combined with low ATP7A expression, good tumor differentiation and female gender were all favorable independent predictive and prognostic factors for patients with resected NSCLC following chemotherapy. High hCtr1 expression combined with low ATP7A expression was associated with an improved prognosis in patients with resected NSCLC that received platinum-based chemotherapy. Surgery combined with neoadjuvant chemotherapy may improve the survival time of patients with NSCLC.

Expression of ERCC1, TYMS, RRM1, TUBB3, non-muscle myosin II, myoglobin and MyoD1 in lung adenocarcinoma pleural effusions predicts survival in patients receiving platinum-based chemotherapy

The association between the expression of excision repair cross‑complementing gene 1 (ERCC1), thymidylate synthase (TYMS), ribonuleotide reductase M1 (RRM1), βIII‑tubulin (TUBB3), non‑muscle myosin II, myoglobin and MyoD1 in metastatic lung adenocarcinoma, and clinical outcomes with platinum‑based chemotherapy treatment is not well‑established. Recently, increasing attention has been focused on the involvement of ERCC1, TYMS, RRM1 and TUBB3 in the development of drug resistance. There has been less research into the role of muscle myosin II, myoglobin and MyoD1 in the pathogenesis of lung cancer, although these genes are known to have important functions within tumor cells. In the current study, malignant pleural effusion from 116 patients with untreated lung adenocarcinoma diagnosed between 2011 and 2012, were collected. The protein expression levels of ERCC1, TYMS, RRM1 and TUBB3 were evaluated with immunocytochemistry and western blot analysis. The expression levels of non‑muscle myosin II, myoglobin and MyoD1 were measured in a subset of 50 patients, treated with platinum‑based chemotherapy. The association of each of these seven factors with one another, as well as with patient survival were analyzed. Immunohistochemistry demonstrated that the percentage of pleural fluid samples from patients with lung adenocarcinoma expressing ERCC1, TYMS, RRM1 and TUBB3 was 37, 36.2, 82.7 and 69.8%, respectively. In the subset of 50 patients in whom the remaining factors were analyzed, the percentage expressing non‑muscle myosin II was 48%, for myoglobin the figure was 40% and for MyoD1 it was 38%. There was a positive correlation between each pair of the above seven molecules with the exception of TYMS and RRM1. Expression of ERCC1, TYMS, TUBB3, non‑muscle myosin II, myoglobin and MyoD1 genes was associated with decreased survival in patients with metastatic lung adenocarcinoma. Expression of ERCC1, TYMS, TUBB3, non‑muscle myosin II, myoglobin and MyoD1 was also associated with decreased survival rates of patients with lung adenocarcinoma treated with platinum‑based chemotherapy. These factors may be used as clinical biomarkers to predict the biological behavior and chemoresistance of tumor cells, and the survival of patients with lung carcinoma.

Pharmacogenomics of cisplatin sensitivity in non-small cell lung cancer

Cisplatin, a platinum-based chemotherapeutic drug, has been used for over 30 years in a wide variety of cancers with varying degrees of success. In particular, cisplatin has been used to treat late stage non-small cell lung cancer (NSCLC) as the standard of care. However, therapeutic outcomes vary from patient to patient. Considerable efforts have been invested to identify biomarkers that can be used to predict cisplatin sensitivity in NSCLC. Here we reviewed current evidence for cisplatin sensitivity biomarkers in NSCLC. We focused on several key pathways, including nucleotide excision repair, drug transport and metabolism. Both expression and germline DNA variation were evaluated in these key pathways. Current evidence suggests that cisplatin-based treatment could be improved by the use of these biomarkers.

Multiple analytical approaches demonstrate a complex relationship of genetic and nongenetic factors with cisplatin- and carboplatin-induced nephrotoxicity in lung cancer patients

Background. Cisplatin and carboplatin cause nephrotoxicity by forming platinum-DNA adducts and lead to cell death. Methods. One-hundred and sixteen Taiwanese lung cancer patients who received cisplatin or carboplatin more than twice were recruited, and their genotypes were determined. The risk of renal dysfunction, injury to the kidney, failure of kidney function, loss of kidney function, and end-stage kidney disease (RIFLE) criteria were used to evaluate the occurrence of nephrotoxicity. A logistic regression, multiple regression with a classification and regression tree (CART), and the Framingham study risk score were used to analyze interactions between genetic and nongenetic factors in producing platinum-induced nephrotoxicity. Results. ERCC1 118C and TP53 72Arg polymorphisms were associated with increased risks of platinum-induced nephrotoxicity. Other risk factors found included the platinum type, baseline serum creatinine (Scr), coadministration of vinorelbine, and the number of chemotherapy cycles. The overall prediction rate of the CART was 82.7%, with a sensitivity of 0.630 and specificity of 0.896. The Framingham study risk prediction model contained 7 factors. Its prediction rate was 84.5%, with a sensitivity of 0.643 and specificity of 0.909. Conclusions. Genetic polymorphisms of ERCC1 and TP53 are risk factors for nephrotoxicity. The CART analysis may provide a clinically applicable model to predict the risk of cisplatin- and carboplatin-induced nephrotoxicity.

Pharmacogenetics of the DNA repair pathways in advanced non-small cell lung cancer patients treated with platinum-based chemotherapy

Genetic variants in DNA repair genes may play a role in the effectiveness of platinum-based chemotherapy in non-small cell lung cancer (NSCLC). We analyzed 17 SNPs in eight genes (ERCC1, ERCC2, ERCC3, ERCC4, ERCC5, XPA, XRCC1 and XRCC2) involved in DNA repair mechanisms and its association with outcome in NSCLC. This prospective study included patients with stages III and IV treated with platinum-based chemotherapy. All patients (n = 161) received cisplatin or carboplatin plus a third-generation drug. Additionally, stage IIIA and IIIB patients (n = 74) received concomitant or sequential radiotherapy. Germline polymorphisms were analyzed using the BioMark system in blood DNA samples. We found that in stage III patients, response was significantly associated with SNPs in ERCC1 and in ERCC3 genes, while radiotherapy-derived toxicity correlated with SNPs in the ERCC2 gene. In stage IV patients, response was associated with a genetic variant in the ERCC4 gene and survival with a SNP in the XRCC1 gene. The complexity of the DNA repair mechanisms along with the heterogeneity in the treatment of lung cancer could explain the role of multiple genes as putative biomarkers of patient outcome.

BMP-4 genetic variants and protein expression are associated with platinum-based chemotherapy response and prognosis in NSCLC

To explore the role of genetic polymorphisms of bone morphogenic proteins 4 (BMP-4) in the response to platinum-based chemotherapy and the clinical outcome in patients with advanced nonsmall cell lung cancer (NSCLC), 938 patients with stage III (A+B) or IV NSCLC were enrolled in this study. We found that the variant genotypes of 6007C > T polymorphisms significantly associated with the chemotherapy response. The 6007CC genotype carriers had a higher chance to be responder to chemotherapy (adjusted odd ratio = 2.77; 95% CI: 1.83–4.18; adjusted < 0.001). The 6007C > T polymorphisms and BMP-4 expression also affect the prognosis of NSCLC. Patients with high BMP-4 expression had a significantly higher chance to be resistant to chemotherapy than those with low BMP-4 expression (OR = 2.81; 95% CI: 1.23–6.44; P = 0.01). The hazard ratio (HR) for 6007TT was 2.37 times higher than 6007CC (P = 0.003). In summary, the 6007C > T polymorphism of BMP-4 gene and BMP-4 tissue expression may be used as potential predictor for the chemotherapy response and prognosis of advanced NSCLC.

A new strategy in the treatment of chemoresistant lung adenocarcinoma via specific siRNA transfection of SRF, E2F1, Survivin, HIF and STAT3

OBJECTIVES

According to the actual treatment strategies of lung cancer, the current therapeutic regimen is an individualized, multidisciplinary concept. The development of chemoresistance in the last decade represents the most important obstacle to an effective treatment. In our study, we examined a new therapeutic alternative in the treatment of multiresistant lung adenocarcinoma via siRNA-specific transfection of six crucial molecules involved in lung carcinogenesis [serum response factor(SFR), E2F1, Survivin, hypoxia inducible factor1 (HIF1), HIF2 and signal transducer and activator of transcription (STAT3)].

METHODS

Three chemoresistant A549 adenocarcinoma cells were cultured under standard conditions at 37°C and 5% CO2. The chemoresistance against Vinflunine, Vinorelbine and Methotrexate was induced artificially. The A549 cells were transfected for 2 h at 37°C with specific siRNA targeting SRF, E2F1, Survivin, HIF1, HIF2 and STAT3 in a non-viral manner. The efficiency of siRNA silencing was evaluated via quantitative real-time polymerase chain reaction, whereas the surviving cells after siRNA transfection as predictor factor for tumoural growth were analysed with a CASY cell counter 3 days after transfection.

RESULTS

The response of the chemotherapeutic resistant adenocarcinoma cells after siRNA transfection was concentration-dependent at both 25 and 100 nM. The CASY analysis showed a very effective suppression of adenocarcinoma cells in Vinorelbine, Vinflunine and Methotrexate groups, with significantly better results in comparison with the control group.

CONCLUSIONS

In our study, we emphasized that siRNA interference might represent a productive platform for further research in order to investigate whether a new regimen in the treatment of multiresistant non-small-cell lung cancer could be established in vivo in the context of a multimodal cancer therapy.

High Sam68 expression predicts poor prognosis in non-small cell lung cancer

BACKGROUND

The nuclear protein Sam68 has been implicated in the oncogenesis and tumor growth. The aim of this study was to explore the clinical value of Sam68 in patients with non-small cell lung cancer (NSCLC).

METHODS

We examined Sam68 expression in 50 NSCLC tissues and matched adjacent noncancerous tissues by quantitative RT-PCR (qRT-PCR) and Western blotting. Furthermore, the Sam68 protein expression was analyzed by immunohistochemistry in 208 NSCLC samples. Kaplan-Meier method and multivariate Cox regression model were used to evaluate the prognostic value of nuclear Sam68 expression in NSCLC for disease survival.

RESULTS

The expression of Sam68 was significantly elevated in NSCLC tissues as compared with adjacent non-cancerous tissues (P < 0.01). The high expression of Sam68 in NSCLC was significantly correlated with lymph node metastasis and tumor TNM stage. Kaplan-Meier survival analysis revealed that high expression of Sam68 correlated with poor prognosis of NSCLC patients (P < 0.01). Multivariate analysis showed that Sam68 expression was an independent prognostic marker for overall survival of NSCLC patients (HR 2.73, 95 % CI 1.549-4.315, P = 0.002).

CONCLUSION

Our results suggest that high Sam68 expression predicts poor prognosis of NSCLC patients, and Sam68 may be potentially a prognostic biomarker for NSCLC.

Mcl-1 mediates TWEAK/Fn14-induced non-small cell lung cancer survival and therapeutic response

Insensitivity to standard clinical interventions, including chemotherapy, radiotherapy, and tyrosine kinase inhibitor (TKI) treatment, remains a substantial hindrance towards improving the prognosis of patients with non-small cell lung cancer (NSCLC). The molecular mechanism of therapeutic resistance remains poorly understood. The TNF-like weak inducer of apoptosis (TWEAK)-FGF-inducible 14 (TNFRSF12A/Fn14) signaling axis is known to promote cancer cell survival via NF-κB activation and the upregulation of prosurvival Bcl-2 family members. Here, a role was determined for TWEAK-Fn14 prosurvival signaling in NSCLC through the upregulation of myeloid cell leukemia sequence 1 (MCL1/Mcl-1). Mcl-1 expression significantly correlated with Fn14 expression, advanced NSCLC tumor stage, and poor patient prognosis in human primary NSCLC tumors. TWEAK stimulation of NSCLC cells induced NF-κB-dependent Mcl-1 protein expression and conferred Mcl-1-dependent chemo- and radioresistance. Depletion of Mcl-1 via siRNA or pharmacologic inhibition of Mcl-1, using EU-5148, sensitized TWEAK-treated NSCLC cells to cisplatin- or radiation-mediated inhibition of cell survival. Moreover, EU-5148 inhibited cell survival across a panel of NSCLC cell lines. In contrast, inhibition of Bcl-2/Bcl-xL function had minimal effect on suppressing TWEAK-induced cell survival. Collectively, these results position TWEAK-Fn14 signaling through Mcl-1 as a significant mechanism for NSCLC tumor cell survival and open new therapeutic avenues to abrogate the high mortality rate seen in NSCLC.

IMPLICATIONS

The TWEAK-Fn14 signaling axis enhances lung cancer cell survival and therapeutic resistance through Mcl-1, positioning both TWEAK-Fn14 and Mcl-1 as therapeutic opportunities in lung cancer.

The (CCTTT)n microsatellite polymorphism in the NOS2 gene may influence lung cancer risk and long-term survival, especially in non-smokers

We analyzed the associations of the NOS2 (CCTTT)n promoter polymorphism to lung cancer risk and tumor histology in smokers and non-smokers. We also investigated lung cancer long-term survival in relation to the polymorphism, smoking data, histology, age at diagnosis, and gender. One hundred eighty-five lung-cancer patients and 164 matched controls, where non-smokers were enriched among the lung cancer cases, were genotyped by fragment analysis and sequencing. Genotypes were combined with information on histology, patient smoking status, and cancer-specific death, using a 20-year follow-up. We divided the (CCTTT)n alleles into short (n ≤ 10), intermediate (n = 11-12), and long (n ≥ 13). Patients homozygous for short repeats had significantly increased risk of lung cancer (p = 0.030) compared to carriers of two long alleles (LL). Lack of long allele was associated with a significantly increased lung cancer risk overall (p = 0.011), especially among non-smokers (p = 0.001). A significantly higher lung cancer survival was seen in non-smokers compared to smokers (p = 0.046) and in low-dose smokers compared to high-dose smokers at the time of diagnosis (p = 0.028). Moreover, non-smoking patients with squamous cell carcinoma (p = 0.015) or adenocarcinoma (p = 0.024) showed a significantly lower survival compared to other lung carcinomas. Nitric oxide can induce proliferation as well as apoptosis depending on cellular context. Our results suggest that the (CCTTT)n NOS2 microsatellite may influence the risk of developing lung cancer, especially in non-smokers, possibly by affecting intracellular nitric oxide levels. Our results also give additional information about the yet poorly understood etiological and prognostic differences between lung cancer in non-smokers and smokers.

SIRT1 expression is associated with the chemotherapy response and prognosis of patients with advanced NSCLC

Aim

The role of Sirtuin 1 (SIRT 1) in carcinogenesis is controversial. This study was to explore the association between the SIRT1 expression and the clinical characteristics, the responsiveness to chemotherapy and prognosis in Non-small cell lung cancer (NSCLC).

Methods

We enrolled 295 patients with inoperable advanced stage of NSCLC, namely, stage III (A+B) and IV NSCLC. All patients had received platinum-based chemotherapy after diagnosis and the chemotherapy response were evaluated. All patients were followed up for overall survival (OS) and progression free survival (PFS). Invitro, H292 cells were tranfected with SIRT1 small interfering RNA (siRNA). The cell biological behaviors and chemosensitivity to cisplatin treatment were studied. The invivo tumorgenesis and metastasis assays were performed in nude mice.

Results

We found that the SIRT1 expressions were significantly associated with the tumor stage, tumor size and differentiation status. Patients with high SIRT 1 expressions had a significantly higher chance to be resistant to chemotherapy than those with low SIRT 1 expression. Patients with high expression of SIRT1 had significantly shorter OS and DFS than those with low expression. Cox analyses confirmed that the SIRT 1 expression was a strong predictor for a poor OS and PFS in NSCLC patients underwent Platinum-based chemotherapy. Invitro studies revealed that the reduced expression SIRT 1 by siRNA technique significantly inhibited cell proliferation, migration and invasion. More importantly, SIRT1 si-RNA significantly enhanced the chemosensitivity of H292 cells to cisplatin treatment. The invivo tumorgenesis and metastasis assays showed that SIRT1 knockdown dramatically reduced the tumor volume and the metastatic ability in nude mice.

Conclusion

Collectively, our data suggest that the SIRT1 expression may be a molecular marker associated with the NSLCLC clinical features, treatment responsiveness and prognosis of advanced NSCLC.

Pharmacogenetics of conventional chemotherapy in non-small-cell lung cancer: a changing landscape?

Pharmacogenetics might be used to select patients who may benefit from specific chemotherapy that best matches the individual and tumor genetic profile, thus allowing maximum activity and minimal toxicity. Even if most studies in non-small-cell lung cancer yielded contradictory results, several potential biomarkers for sensitivity/resistance to platinum compounds, gemcitabine, taxanes and pemetrexed have been proposed. However, these markers need to be validated within larger prospective randomized trials of customized chemotherapy in homogeneous populations. Other critical points include the optimization/standardization of technical procedures, and further studies to unravel the extremely complex regulation of gene function. From this perspective, the evaluation of key factors influencing genotype-phenotype relationships, such as miRNAs, and functional studies to clarify pharmacokinetic/pharmacodynamic interactions, are fundamental for the pharmacogenetic optimization of cancer chemotherapy. Finally, limitation of the traditional pharmacogenetic approach relying only on candidate genes suspected of affecting drug response is now being overcome by the use of novel genome-wide studies.

TMEM158 and FBLP1 as novel marker genes of cisplatin sensitivity in non-small cell lung cancer cells

Even after development of molecular targeting therapies, platinum-based chemotherapy is still a standard care for treatment of locally advanced non-small cell lung cancer (NSCLC). So far, critical molecular markers capable to predict the therapeutic response in NSCLC patients remain undetermined. We here attempted to identify novel biomarker genes for cisplatin (CDDP) for a tailored therapy. Initial screening to explorer association of IC(50) values of CDDP obtained by MTT assay and gene expression levels measured with oligonucleotide microarray and real-time RT-PCR provided 6 candidate genes, namely, NUBPL, C9orf30, ZNF12, TMEM158, GSK3B, and FBLP1 using 9 lung cancer cells consisting of 3 small and 6 NSCLC cells. These 6 genes together with 5 reported biomarkers, i.e., GSTP1, ERCC1, BRCA1, FRAP1, and RRM1, were subjected to a linear regression analysis using 12 NSCLC cell lines including 6 additional NSCLC cells: only FBLP1 and TMEM158 genes showed positive associations with statistical significances (P = .016 and .026, respectively). The biological significance of these genes was explored by in vitro experiments: Knockdown experiments in PC-9/CDDP cells revealed that the reduced expression of TMEM158 significantly decreased the chemo-resistance against CDDP (P <.0001), while 2 transformants of PC-6 cells stably over-expressing FBLP1 resulted in an enhanced resistance to CDDP (P = .004 and P = .001). Furthermore, a stepwise multiple regression analysis demonstrated the best prediction formula could be fixed when we used expression data of TMEM158 and FBLP1 (R(2) = 0.755, P = .0018). TMEM158 and FBLP1 may be powerful predictive biomarkers for CDDP therapy in NSCLC.

MicroRNA-related genetic variants associated with clinical outcomes in early-stage non-small cell lung cancer patients

Given the density of single-nucleotide polymorphisms (SNP) in the human genome and the sensitivity of single-nucleotide changes in microRNA (miRNA) functionality and processing, we asked whether polymorphisms within miRNA processing pathways and binding sites may influence non-small cell lung cancer (NSCLC) patients' prognosis. We genotyped 240 miRNA-related SNPs in 535 patients with stage I and II NSCLCs to determine associations with overall recurrence and survival as well as effect in specific treatment subgroups. After correcting for multiple comparisons, the G allele of FZD4:rs713065 displayed a significant association with decreased risk of death in surgery-only patients [HR, 0.46; 95% confidence interval (CI), 0.32-0.65]. DROSHA:rs6886834 variant A allele (HR, 6.38; 95% CI, 2.49-16.31) remained significant for increased risk of recurrence in the overall and surgery-only populations, respectively. FAS:rs2234978 G allele remained significantly associated with survival in all patients (HR, 0.59; 95% CI, 0.44-0.77), whereas borderline significant in subgroups (surgery-only: HR, 0.59; 95% CI, 0.42-0.84; surgery plus chemo: HR, 0.19; 95% CI, 0.07-0.46). Luciferase assays showed that the FAS SNP created a miR-651 functional binding site. Survival tree analysis was conducted to classify patients into distinct risk subgroups based on their risk genotype combinations. These results indicate that miRNA-related polymorphisms may be associated with NSCLC patients' clinical outcomes through altered miRNA regulation of target genes.

Overcoming challenges of ovarian cancer stem cells: novel therapeutic approaches

Understanding the genetic and molecular mechanisms of ovarian cancer has been the focus of research efforts working toward the greater goal of improving cancer therapy for patients with residual disease after initial treatment with conventional surgery and neoadjuvant chemotherapy. The focus of this review will be centered on new therapeutic strategies based on Cancer Stem Cells studies of chemoresistant subpopulations, the prevention of metastasis, and individualized therapy in order to find the most successful combination of treatments to effectively treat human ovarian cancer. We reviewed recent literature (1993-2011) of novel treatment approaches to ovarian cancer stem cells. As the focus of ovarian cancer investigation has centered on the cancer stem cell model and the complexities that it presents in the development of effective treatments, the future of treating ovarian cancer lies in utilizing individualized treatment systems that include enhancing existing treatments, aiming for novel therapy targets, managing the plasticity of stem cells to induce cellular differentiation, and regulating oncogenic signaling pathways.

Multi-loci analysis reveals the importance of genetic variations in sensitivity of platinum-based chemotherapy in non-small-cell lung cancer

Polymorphisms in DNA repair and apoptotic pathways may cause variations in chemosensitivity of non-small-cell lung cancer (NSCLC) through complex gene-gene and gene-environment interactions. A total of 200 advanced NSCLC patients who received platinum-based chemotherapies were recruited. The short-term clinical outcomes were classified as chemosensitive group, including complete remission (CR) and partial remission (PR), and chemoresistant group, namely stable disease (SD) and progression disease (PD) at the end of treatment. We applied multifactor dimensionality reduction (MDR), classification and regression tree (CART) and traditional logistic regression (LR) to explore high-order gene-gene and gene-environment interactions among 11 functional single nucleotide polymorphisms (SNPs), smoking status, cancer stages and treatment regimens in the response to chemotherapy. Multi-loci analyses consistently indicated that interactions among XRCC1 Arg194Trp, XPC PAT, FAS G-1377A, and FASL T-844C were associated with sensitivity to platinum-based chemotherapy. In MDR analysis, the four-factor model yielded the highest test accuracy of 0.72 (permutation P = 0.001). In CART analysis, these four SNPs were the determinant nodes of the growth of regression tree. Patients carrying XRCC1 Arg194Arg, FAS-1377GG, and FASL-844T allele displayed completely no response to platinum, whereas patients with XRCC1 194Trp allele and XPC PAT +/+ had 68.8% response rate to platinum. In LR analysis, a significant gene-dosage effect was detected along with the increasing number of favorable genotypes of these four polymorphisms (P trend = 0.00002). Multi-loci analysis reveals the importance of genetic variations involved in DNA repair and apoptotic pathways in sensitivity of platinum-based chemotherapy in NSCLC.

Meta-analysis on pharmacogenetics of platinum-based chemotherapy in non small cell lung cancer (NSCLC) patients

AIM

To determine the pharmacogenetics of platinum-based chemotherapy in Non Small Cell Lung Cancer (NSCLC) patients.

METHODS

Publications were selected from PubMed, Cochrane Library and ISI Web of Knowledge. A meta-analysis was conducted to determine the association between genetic polymorphisms and platinum-based chemotherapy by checking odds ratio (OR) and 95% confidence interval (CI).

RESULTS

Data were extracted from 24 publications, which included 11 polymorphisms in 8 genes for meta-analysis. MDR1 C3435T (OR = 1.97, 95% CI: 1.11-3.50, P = 0.02), G2677A/T (OR = 2.61, 95% CI: 1.44-4.74, P = 0.002) and GSTP1 A313G (OR = 0.32, 95% CI: 0.17-0.58, P = 0.0002) were significantly correlated with platinum-based chemotherapy in Asian NSCLC patients.

CONCLUSION

Attention should be paid to MDR1 C3435T, G2677A/T and GSTP1 A313G for personalized chemotherapy treatment for NSCLC patients in Asian population in the future.

[Effect of the XRCC1 and XRCC3 genetic polymorphisms on the efficacy of platinum-based chemotherapy in patients with advanced non-small cell lung cancer]

背景与目的

DNA修复基因多态性预测铂类药物化疗敏感性对非小细胞肺癌(non-small cell lung cancer, NSCLC)个体化治疗具有重要意义。本研究旨在探讨X线修复交错互补基因1(X-ray repair cross complementing gene 1, XRCC1)和X线修复交错互补基因3(X-ray repair cross complementing gene 3, XRCC3)单核苷酸多态性与晚期NSCLC患者对铂类药物化疗疗效的关系。

方法

采用PCR-RFLP方法检测130例以含铂方案化疗的晚期NSCLC患者外周血DNA中XRCC1 Arg194 Trp、Arg399 Gln和XRCC3 Thr241 Met基因多态性, 分析其基因型与化疗疗效的关系。

结果

130例晚期NSCLC患者采用含铂方案化疗2个周期后, 化疗总有效率为33.8%。XRCC1 194和399基因多态性与铂类药物化疗敏感性相关, 而XRCC3 241基因多态性与化疗敏感性无关(P=0.145)。携带至少1个XRCC1 194 Trp等位基因者化疗有效率至少是携带Arg/Arg基因型患者的2.5倍(42.1% vs 22.2%, OR=2.545, 95%CI:1.159-5.590, P=0.020)。携带XRCC1 399 Arg/Arg基因型者的化疗有效率为45.5%, 明显高于携带至少1个Gln等位基因者(21.9%)(OR=0.336, 95%CI:0.156-0.722, P=0.005)。XRCC1 194和399基因多态性之间存在联合作用, 同时携带至少1个XRCC1 194 Trp等位基因和399 Arg/Arg基因型者的化疗有效率明显高于同时携带194 Arg/Arg和399 Arg/Gln基因型者(44.4% vs 18.8%, OR=3.467, 95%CI:1.223-9.782, P=0.019)。XRCC1和XRCC3基因多态性在化疗敏感性方面存在一定的联合作用, 携带至少1个XRCC1 194 Trp等位基因和399 Arg/Arg野生型基因同时又携带XRCC3 241 Thr/Met基因型者的化疗有效率明显高于其它基因型携带者。

结论

XRCC1和XRCC3的多态联合可能与晚期NSCLC患者对铂类药物化疗疗效具有相关性。

An intronic polymorphism in GRP78 improves chemotherapeutic prediction in non-small cell lung cancer

BACKGROUND

Glucose-regulated protein 78 (GRP78) is involved in not only the progression of non-small cell lung cancer (NSCLC) but also chemotherapeutic effects. We hypothesized that an intronic polymorphism (rs430397G>A) in GRP78 affects survival among patients with NSCLC treated with platinum-based chemotherapy.

METHODS

Blood samples of patients with advanced NSCLC (IIIB/IV) were maintained in our specimen bank between 2001 and 2006. Genomic DNA was genotyped for rs430397. Associations between rs430397 and platinum-based treatment response, overall survival (OS), NSCLC-related survival, progression-free survival (PFS), and relapses were evaluated. GRP78 RNA and protein in NSCLC tissues were tested by real-time polymerase chain reaction and immunohistochemistry.

RESULTS

The AA genotype is significantly associated with platinum-based chemoresistance (P = .019) and NSCLC-related death (P = .022). OS, NSCLC-related survival, and PFS of the AA genotype group are decreased compared with the GG and AG genotype groups (log-rank P < .05, respectively). The AA group showed a higher prevalence of early NSCLC relapses than the AG and GG group (P = .030). In addition, the AA genotype showed a significantly increased risk for OS (hazard ratio, 1.95) and PFS (hazard ratio, 1.80) compared with the GG group. Functional analysis showed that NSCLC tissues with genotype AA have higher GRP78 RNA and protein expression compared with those carrying GG at rs430397.

CONCLUSIONS

The rs430397 AA genotype of GRP78 is associated with reduced survival and higher prevalence of early relapses in patients with advanced NSCLC treated with platinum-based chemotherapy.

DNA repair gene polymorphism associated with sensitivity of lung cancer to therapy

This study aimed to investigate association between single-nucleotide polymorphisms (SNPs) of excision repair cross-complementing gene 1 (ERCC1), excision repair cross-complementing gene 2 (ERCC2), and X-ray repair cross-complementing group 1 (XRCC1) with sensitivity of advanced non-small cell lung cancer (NSCLC) patients to platinum-based chemotherapy. A total of 89 NSCLC patients were recruited and treated with two cycles of platinum-based chemotherapy. DNA was extracted from peripheral lymphocytes for detection of SNPs of ERCC1 Asn118Asn, ERCC2 Lys751Gln, and XRCC1 Arg399Gln. The overall response rate of these patients was 29.2%. There was no statistically significant difference of treatment response between the wild genotypes and the variant genotypes for the ERCC1 Asn118Asn and ERCC2 Lys751Gln gene. The distributions of genotypes XRCC1 Arg399Gln differed significantly between the response and non-response groups (76.9 vs. 23.1%, P = 0.001). The XRCC1 399Arg/Arg genotype carriers had a higher response rate than that of the Gln genotype carriers (OR = 4.81, 95%CI = 1.778-13.013, P = 0.002). The combination of the favorable genotypes of ERCC1, ERCC2, and XRCC1 had a higher response rate compared to that of patients with other genotypes. The combined polymorphisms of ERCC1, ERCC2, and XRCC1 may be associated with sensitivity of NSCLC to platinum-based chemotherapy. Further studies will verify these SNPs as biomarkers for prediction of platinum-based chemotherapy responses of NSCLC patients.