Serum reactive oxygen species modulator 1 (Romo1) as a potential diagnostic biomarker for non-small cell lung cancer

Conducting polymer composite-based biosensing materials for the diagnosis of lung cancer: A review

The development of a simple and fast cancer detection method is crucial since early diagnosis is a key factor in increasing survival rates for lung cancer patients. Among several diagnosis methods, the electrochemical sensor is the most promising one due to its outstanding performance, portability, real-time analysis, robustness, amenability, and cost-effectiveness. Conducting polymer (CP) composites have been frequently used to fabricate a robust sensor device, owing to their excellent physical and electrochemical properties as well as biocompatibility with nontoxic effects on the biological system. This review brings up a brief overview of the importance of electrochemical biosensors for the early detection of lung cancer, with a detailed discussion on the design and development of CP composite materials for biosensor applications. The review covers the electrochemical sensing of numerous lung cancer markers employing composite electrodes based on the conducting polyterthiophene, poly(3,4-ethylenedioxythiophene), polyaniline, polypyrrole, molecularly imprinted polymers, and others. In addition, a hybrid of the electrochemical biosensors and other techniques was highlighted. The outlook was also briefly discussed for the development of CP composite-based electrochemical biosensors for POC diagnostic devices.

Targeting PKLR/MYCN/ROMO1 signaling suppresses neuroendocrine differentiation of castration-resistant prostate cancer

Conventional treatment of prostate cancer (PCa) uses androgen-deprivation therapy (ADT) to inhibit androgen receptor (AR) signaling-driven tumor progression. ADT-induced PCa recurrence may progress to an AR-negative phenotype with neuroendocrine (NE) histologic features, which are associated with metabolic disturbances and poor prognoses. However, the metabolic pathways that regulate NE differentiation (NED) in PCa remain unclear. Herein, we show a regulatory mechanism in NED-associated metabolism dysfunction induced by ADT, whereby overexpression of pyruvate kinase L/R (PKLR) mediates oxidative stress through upregulation of reactive oxygen species modulator 1 (ROMO1), thereby promoting NED and aggressiveness. ADT mediates the nuclear translocation of PKLR, which binds to the MYCN/MAX complex to upregulate ROMO1 and NE-related genes, leading to altered mitochondrial function and NED of PCa. Targeting nuclear PKLR/MYCN using bromodomain and extra-terminal motif (BET) inhibitors has the potential to reduce PKLR/MYCN-driven NED. Abundant ROMO1 in serum samples may provide prognostic information in patients with ADT. Our results suggest that ADT resistance leads to upregulation of PKLR/MYCN/ROMO1 signaling, which may drive metabolic reprogramming and NED in PCa. We further show that increased abundance of serum ROMO1 may be associated with the development of NE-like PCa.

Blood protein biomarkers in lung cancer

Lung cancer has consistently ranked first as the cause of cancer-associated mortality. The 5-year survival rate has risen slowly, and the main obstacle to improving the prognosis of patients has been that lung cancer is usually diagnosed at an advanced or incurable stage. Thus, early detection and timely intervention are the most effective ways to reduce lung cancer mortality. Tumor-specific molecules and cellular elements are abundant in circulation, providing real-time information in a noninvasive and cost-effective manner during lung cancer development. These circulating biomarkers are emerging as promising tools for early detection of lung cancer and can be used to supplement computed tomography screening, as well as for prognosis prediction and treatment response monitoring. Serum and plasma are the main sources of circulating biomarkers, and protein biomarkers have been most extensively studied. In this review, we summarize the research progress on three most common types of blood protein biomarkers (tumor-associated antigens, autoantibodies, and exosomal proteins) in lung cancer. This review will potentially guide researchers toward a more comprehensive understanding of candidate lung cancer protein biomarkers in the blood to facilitate their translation to the clinic.

Identification of reactive oxygen species modulator 1 (Romo 1) from black rockfish (Sebastes schlegelii) and deciphering its molecular characteristics, immune responses, oxidative stress modulation, and wound healing properties

Reactive oxygen species modulator 1 (Romo1) is a mitochondrial inner membrane protein that induces mitochondrial reactive oxygen species (ROS) generation. In this study, we identified the Romo1 homolog from the black rockfish (Sebastes schlegelii), named it as SsRomo1, and characterized it at the molecular as well as functional levels. An open reading frame consisting of 240 bp was identified in the SsRomo1 complementary DNA (cDNA) sequence that encodes a 79 amino acid-long polypeptide with a molecular weight of 8,293 Da and a theoretical isoelectric point (pI) of 9.89. The in silico analysis revealed the characteristic features of SsRomo1, namely the presence of a transmembrane domain and the lack of a signal peptide. Homology analysis revealed that SsRomo1 exhibits the highest sequence identity with its fish counterparts (>93%) and shares a similar percentage of sequence identity with mammals (>92%). Additionally, it is closely clustered together with the fish clade in the constructed phylogenetic tree. The subcellular localization analysis confirmed its mitochondrial localization within the fathead minnow (FHM) cells. Under normal physiological conditions, the SsRomo1 mRNA is highly expressed in the rockfish ovary, followed by the blood and testis, indicating the abundance of mitochondria in these tissues. Furthermore, the significant upregulation of SsRomo1 in cells treated with lipopolysachharide (LPS), polyinosinic:polycytidylic acid, and Streptococcus iniae suggest that the increased ROS production is induced by SsRomo1 to eliminate pathogens during infections. Incidentally, we believe that this study is the first to determine the involvement of SsRomo1 in LPS-mediated nitric oxide (NO) production in RAW267.4 cells, based on their higher NO production as compared to that in the control. Moreover, overexpression of SsRomo1 enhanced the wound healing ability of FHM cells, indicating its high invasion and migration properties. We also determined the hydrogen peroxide-mediated cell viability of SsRomo1-overexpressed FHM cells and observed a significant reduction in viability, which is possibly due to increased ROS production. Collectively, our observations suggest that SsRomo1 plays an important role in oxidative stress modulation upon immune stimulation and in maintenance of tissue homeostasis in black rockfish.

Serum Reactive Oxygen Species Modulator 1 as a Novel Predictive Biomarker for Resected Lung Adenocarcinoma: A Retrospective Pilot Study

Purpose

Reactive oxygen species modulator 1 (Romo1) is a key regulator of intracellular reactive oxygen species production. Previous studies have shown that Romo1 overexpression in tumor tissue is associated with poor clinical outcomes in various clinical settings for lung cancer treatment. The aim of the present study was to assess the predictive value of serum Romo1 in patients received curative resection for lung cancer.

Methods

Serum samples were collected from patients with lung adenocarcinoma who underwent surgical resection. Baseline serum Romo1 and carcinoembryonic antigen (CEA) levels before surgery were measured. Univariate and multivariate analyses were performed to identify whether serum Romo1 was associated with disease-free survival (DFS).

Results

A total of 77 samples were analyzed. Using the cut-off value of 866 pg/mL, the population was classified into low (n = 42, 54.4%) and high (n = 35, 45.4%) Romo1 groups. The median DFS of the high Romo1 group was significantly shorter than that of the low Romo1 group (25.5 months vs not reached [NR], p = 0.0105). In addition, the median DFS of patients in the high CEA (>2.9 ng/mL) group was significantly shorter than those in the low CEA group (26.8 months vs NR, p = 0.0092). Multivariate analyses showed that both high Romo1 and CEA levels were independently associated with poor DFS (hazard ratio [HR] = 2.19; 95% confidence interval [CI]: 1.14–8.37, and HR = 2.95; 95% CI: 1.23–9.21, respectively). Moreover, combination of these two biomarkers resulted in higher HR of 4.11 (95% CI, 1.53–14.05) for DFS than those of Romo1 and CEA.

Conclusion

Elevated serum Romo1 levels were significantly associated with early recurrence in patients with lung adenocarcinoma treated with surgical resection. Serum Romo1 may be a promising predictive biomarker for this patient population.

Pleural biomarkers in diagnostics of malignant pleural effusion: a narrative review

Although cytology and pleural biopsy of pleural effusion (PE) are the gold standards for diagnosing malignant pleural effusion (MPE), these tools’ diagnostic accuracy is plagued by some limitations such as low sensitivity, considerable inter-observer variation and invasiveness. The assessment of PE biomarkers may hence be seen as an objective and non-invasive diagnostic alternative in MPE diagnostics. In this review, we summarize the characteristics and diagnostic accuracy of available PE biomarkers, including carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), carbohydrate antigens 125 (CA125), carbohydrate antigen 19-9 (CA19-9), carbohydrate antigen 15-3 (CA15-3), a fragment of cytokeratin 19 (CYFRA 21-1), chitinase-like proteins (CLPs), vascular endothelial growth factor (VEGF) and its soluble receptor, endostatin, calprotectin, cancer ratio, homocysteine, apolipoprotein E (Apo-E), B7 family members, matrix metalloproteinase (MMPs) and tissue-specific inhibitors of metalloproteinases (TIMPs), reactive oxygen species modulator 1 (Romo1), tumor-associated macrophages (TAMs) and monocytes, epigenetic markers (e.g., cell-free microRNA and mRNA). We summarized the evidence from systematic review and meta-analysis for traditional tumor markers’ diagnostic accuracy. According to the currently available evidence, we conclude that the traditional tumor markers have high specificity (around 0.90) but low sensitivity (around 0.50). The diagnostic accuracy of novel tumor markers needs to be validated by further studies. None of these tumor biomarkers would have sufficient diagnostic accuracy to confirm or exclude MPE when used alone. A multi-biomarker strategy, also encompassing the use of artificial intelligence algorithms, may be a valuable perspective for improving the diagnostic accuracy of MPE.

The C allele of the reactive oxygen species modulator 1 (ROMO1) polymorphism rs6060566 is a biomarker predicting coronary artery stenosis in Slovenian subjects with type 2 diabetes mellitus

BACKGROUND

We aimed to examine the role of the rs6060566 polymorphism of the reactive oxygen species modulator 1 (ROMO1) gene in the development of myocardial infarction (MI) in Caucasians with type 2 diabetes (T2DM).

METHODS

A total of 1072 subjects with T2DM were enrolled in this cross-sectional case-control study: 335 subjects with MI and 737 subjects without clinical signs of coronary artery disease (CAD). The genetic analysis of the rs6060566 polymorphism was performed in all subjects. To assess the degree of coronary artery obstruction, a subpopulation of 128 subjects with T2DM underwent coronary computed tomography angiography. Next, endarterectomy samples were obtained during myocardial revascularization from diffusely diseased coronary arteries in 40 cases, which were analysed for ROMO1 expression according to their genotype.

RESULTS

There were no statistically significant associations between different genotypes or alleles of the rs6060566 polymorphism and MI in subjects with T2DM. The carriers of the C allele of the ROMO1 rs6060566 had a threefold increased likelihood of having 50-75% coronary artery stenosis (Adjusted OR = 3.27, 95% CI 1.16-9.20). Subjects with two affected coronary arteries had a 3.72 fold higher prevalence of MI (OR = 3.72, 95% CI 1.27-10.84). With CAD in LMCA or LAD, MI prevalence was about 3.5-fold higher (p = 0.07 for LMCA and p = 0.01 for LAD). Furthermore, the carriers of the rs6060566 C allele showed higher number of positive cells for ROMO1 expression in endarterectomy samples of coronary arteries.

CONCLUSIONS

According to our study, the rs6060566 polymorphism of the ROMO1 gene is not a risk factor for MI in Caucasians with T2DM. However, we found that subjects carrying the C allele were at a 3.27-fold increased risk of developing severe CAD compared with those who had non-obstructive CAD. Moreover, C allele carriers showed a statistically higher number of cells positive for ROMO1 compared with T allele carriers in coronary endarterectomy samples.

Increased Serum Romo1 Was Correlated with Lung Function, Inflammation, and Oxidative Stress in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is associated with abnormal inflammation and high oxidative stress. Studies suggest that reactive oxygen species modulator 1 (Romo1) involve in diseases associated with oxidative stress and inflammation. However, the relationship between COPD and Romo1 is still not clear. In this study, we compared serum Romo1 in 49 COPD patients and 34 health controls, and their correlation with lung function, systematic inflammation, and oxidative stress. In addition, serum levels of Romo1, C-reactive protein (CRP), and oxidative stress (measured by reactive oxygen species, ROS) were analyzed using commercial kits. Serum Romo1 was significantly higher in COPD patients than that of control (132.24 ± 10.34 vs. 93.26 ± 7.75 pg/ml, P < 0.05). Serum CRP and ROS were also significantly higher in COPD patients. Serum Romo1 was correlated inversely with FEV1% predicted in COPD patients (푟 = - 0.347, 푃 = 0.016), while it was correlated positively with CRP and ROS levels, respectively. These results suggest that serum Romo1 increase in COPD patients and that these levels are associated with lung function, inflammation, and oxidative stress in COPD.

Clinical value of combined detection of reactive oxygen species modulator 1 and adenosine deaminase in pleural effusion in the identification of NSCLC associated malignant pleural effusion

Background

Reactive oxygen species modulator 1 (ROMO1) is recognized to be involved in cell proliferation and is elevated in serum of various cancer patients. However, ROMO1 had little research in distinguishing between malignant pleural effusions (MPEs) and benign pleural effusions (BPEs).

Methods

Malignant pleural effusion samples from patients with non–small‐cell lung cancer (NSCLC) and benign pleural effusion (BPE) samples containing tuberculous and inflammatory pleural effusions were collected. The samples were tested for ROMO1, pleural effusion adenosine deaminase (pADA), pleural effusion carbohydrate antigen (pCA125, pCA153, pCA199), pleural effusion ferritin (pFER), and pleural effusion lactate dehydrogenase (pLDH) levels, and the other relevant partial clinical data that were gathered were used to conduct statistical analysis.

Results

The ROMO1, pCA125, pCA199, pCA153, pADA + ROMO1, pCA153 + ROMO1, pCA125 + ROMO1, and pCA199 + ROMO1 levels in MPE were appreciably higher in comparison with BPE group (all P = .000). The concentration of pADA in MPE was markedly lower than BPE (P = .000). When the cutoff = 0.38, the sensitivity of combined detection of ROMO1 + pADA is 98.67% and the specificity is 70.73%, respectively, and the AUC (0.941) is the highest among other parameters.

Conclusion

The combined detection of ROMO1 + ADA in pleural effusion is an effective biomarker for identifying MPE caused by NSCLC.

Reactive Oxygen Species Modulator 1 As An Adverse Prognostic Marker In Stage III Non-Small Cell Lung Cancer Treated With Radiotherapy: A Retrospective Pilot Study

Purpose

Reactive oxygen species modulator 1 (ROMO1) is a novel protein regulating intracellular reactive oxygen species production. Although increased ROMO1 expression has been associated with poor clinical outcomes in several human malignancies, the clinical implication of this protein in a radiotherapy setting has never been explored. The aim of this study was to investigate whether ROMO1 expression is associated with survival in lung cancer patients who received radiotherapy.

Methods

ROMO1 protein expression was evaluated immunohistochemically using histologic score (H-score) in 49 tumor tissues from stage III non-small cell lung cancer (NSCLC) patients treated with definitive radiotherapy. We performed survival analyses according to various clinicopathological parameters including ROMO1 expression.

Results

ROMO1 expression was not associated with any clinicopathological parameter of age, sex, smoking status, stage, or histological subtype. Multivariate analyses showed that high ROMO1 expression was independently associated with worse progression-free survival (hazard ratio [HR] = 1.87, 95% confidence interval [CI]: 1.02-4.23) and with worse overall survival (HR = 2.79, 95% CI:1.13-6.87). In addition, high ROMO1 expression was independently associated with shorter time to loco-regional recurrence (HR=2.71, 95% CI:1.04-6.28) but was not associated with time to distant metastasis.

Conclusion

ROMO1 overexpression was associated with early loco-regional recurrence and poor survival outcomes in stage III NSCLC treated with definitive radiotherapy. Our exploratory results provide a basis for further large-scale studies to validate whether ROMO1 could be a prognostic marker in this setting.

Reactive Oxygen Species Modulator 1 (ROMO1), a New Potential Target for Cancer Diagnosis and Treatment

Today, the incidence of cancer in the world is rising, and it is expected that in the next several decades, the number of people suffering from cancer or (the cancer rate) will double. Cancer is defined as the excessive and uncontrolled growth of cells; of course (in simple terms), cancer is considered to be a set of other diseases that ultimately causes normal cells to be transformed into neoplastic cells. One of the most important causes of the onset and exacerbation of cancer is excessive oxidative stress. One of the most important proteins in the inner membrane of mitochondria is Reactive Oxygen Species (ROS) Modulator 1 (ROMO1) that interferes with the production of ROS, and with increasing the rate of this protein, oxidative stress will increase, which ultimately leads to some diseases, especially cancer. In this overview, we use some global databases to provide information about ROMO1 cellular signaling pathways, their related proteins and molecules, and some of the diseases associated with the mitochondrial protein, especially cancer.

Serum Romo1 is significantly associated with disease severity in patients with obstructive sleep apnea syndrome

PURPOSE

We aim to evaluate reactive oxygen species modulator 1 (Romo1) levels in obstructive sleep apnea syndrome (OSAS) and analyze its possible relationships to OSAS severity, reactive oxygen species (ROS), and C-reactive protein (CRP). Additionally, we also investigated the effects of nasal continuous positive airway pressure (nCPAP) on serum Romo1.

METHODS

One hundred and five patients diagnosed with OSAS were classified into the OSAS group, and 41 subjects without OSAS were recruited for the control group. The OSAS group was further divided into mild, moderate, and severe OSAS subgroups. Fifteen patients with moderate and severe OSAS were treated with nCPAP. Serum levels of Romo1, ROS, and CRP were also measured.

RESULTS

Serum Romo1, ROS, and CRP were the lowest in normal subjects and increased across OSAS severities (P < 0.05). Univariate analysis showed that serum Romo1 was positively correlated with apnea-hypopnea index (AHI), oxygen desaturation index (ODI), time spent below 90% oxygen saturation (Ts90%), arousal index, ROS, and CRP, and was negatively correlated with minimal oxygen saturation (miniSaO₂) (all P < 0.05). Multiple linear regression analysis showed that serum Romo1 level was significantly associated with AHI and ODI, after adjusting for age, gender, BMI, and CRP. After 6 months of nCPAP therapy, serum Romo1, ROS, and CRP were significantly decreased (P < 0.05).

CONCLUSIONS

The increase of serum Romo1 in OSAS patients was positively correlated with disease severity. Serum Romo1 may be an important parameter for monitoring the severity of OSAS and treatment efficiency.

Identification of ubiquinol cytochrome c reductase hinge (UQCRH) as a potential diagnostic biomarker for lung adenocarcinoma

Ubiquinol cytochrome c reductase hinge (UQCRH) is a novel protein that localizes in the mitochondrial membrane and induces mitochondrial reactive oxygen species (ROS) generation. It had a high expression rate of 87.10% (108/124) in lung adenocarcinoma. Moreover, serum UQCRH level in patients with lung adenocarcinoma was significantly increased compared with that of pneumonia patients (p < 0.0001) and normal control subjects (p < 0.0001). Receiver operating characteristic curve analysis using an optimal cut-off value of 162.65 pg ml⁻¹ revealed sensitivity and specificity for the diagnosis of lung adenocarcinoma of 88.7% and 85.7%, respectively, with an area under the curve of 0.927 (95% CI: 0.892 to 0.962, p < 0.0001). Serum UQCRH discriminates lung adenocarcinoma patients from the population without cancer with considerable sensitivity and specificity, but it does not distinguish between heavy smokers and lung adenocarcinoma patients. Serum UQCRH could be a potential diagnostic biomarker for lung adenocarcinoma.

Reactive oxygen species modulator 1, a novel protein, combined with carcinoembryonic antigen in differentiating malignant from benign pleural effusion

The differential diagnosis of malignant pleural effusion and benign pleural effusion remains a clinical problem. Reactive oxygen species modulator 1 is a novel protein overexpressed in various human tumors. The objective of this study was to evaluate the diagnostic value of joint detection of reactive oxygen species modulator 1 and carcinoembryonic antigen in the differential diagnosis of malignant pleural effusion and benign pleural effusion. One hundred two consecutive patients with pleural effusion (including 52 malignant pleural effusion and 50 benign pleural effusion) were registered in this study. Levels of reactive oxygen species modulator 1 and carcinoembryonic antigen were measured by enzyme-linked immunosorbent assay and radioimmunoassay, respectively. Results showed that the concentrations of reactive oxygen species modulator 1 both in pleural fluid and serum of patients with malignant pleural effusion were significantly higher than those of benign pleural effusion (both p < 0.05). The diagnostic sensitivity and specificity of pleural fluid reactive oxygen species modulator 1 were 61.54% and 82.00%, respectively, with the optimized cutoff value of 589.70 pg/mL. However, the diagnostic sensitivity and specificity of serum reactive oxygen species modulator 1 were only 41.38% and 86.21%, respectively, with the cutoff value of 27.22 ng/mL, indicating that serum reactive oxygen species modulator 1 may not be a good option in the differential diagnosis of malignant pleural effusion and benign pleural effusion. The sensitivity and specificity of pleural fluid carcinoembryonic antigen were 69.23% and 88.00%, respectively, at the cutoff value of 3.05 ng/mL, while serum carcinoembryonic antigen were 80.77% and 72.00% at the cutoff value of 2.60 ng/mL. The sensitivity could be raised to 88.17% in parallel detection of plural fluid reactive oxygen species modulator 1 and carcinoembryonic antigen concentration, and the specificity could be improved to 97.84% in serial detection.

Reactive oxygen species modulator-1 (Romo1) predicts unfavorable prognosis in colorectal cancer patients

Background

Reactive oxygen species modulator-1 (Romo1) is a novel protein that has been reported to be crucial for cancer cell proliferation and invasion. However, its clinical implications in colorectal cancer patients are not well-known. For the first time, we investigated the association between Romo1 and the clinical outcomes of colorectal cancer patients.

Study

We examined Romo1 expression in resected tumor tissues immunohistochemically and assessed it with histological scores. We conducted survival analyses for patients who had curative resection (n = 190) in accordance with clinical parameters including level of Romo1 expression, and we examined the association between Romo1 expression and cell invasion using Matrigel invasion assay in colorectal cancer cells.

Results

We observed significantly longer mean disease-free survival in the low Romo1 group compared with the high Romo1 group (161 vs 127.6 months, p = 0.035), and the median overall survival of the low Romo1 group was significantly longer than that of the high Romo1 group (196.9 vs 171.3 months, p = 0.036). Cell invasiveness decreased in the Romo1 knockdown colorectal cancer cells in contrast to the controlled cells. Romo1 overexpression in tumor tissue was associated with a high lymph node ratio between the metastatic and examined lymph nodes (p = 0.025).

Conclusions

Romo1 overexpression in tumor tissue was significantly associated with survival in curatively resected colorectal cancer patients, suggesting Romo1 expression as a potential adverse prognostic marker. Increased Romo1 expression was found to be associated with high lymph node ratio. Cancer invasiveness appeared to be a key reason for the poor survival related to highly expressed Romo1.

Reactive oxygen species modulator 1 (Romo1) as a novel diagnostic marker for lung cancer-related malignant effusion

Reactive oxygen species modulator 1 (Romo1) is a novel protein that plays an important role in intracellular reactive oxygen species generation. Recently, Romo1 has been suggested to have diagnostic and prognostic potential in lung cancer. However, there is no data on the diagnostic value of Romo1 level in malignant pleural effusion. We evaluated the clinical usefulness of Romo1 in pleural fluid for the diagnosis of malignant effusion in lung cancer patients. Pleural fluid Romo1 level was measured using enzyme-linked immunosorbent assay and compared between lung cancer-associated malignant effusion (n = 53; 29 adenocarcinomas and 24 squamous cell carcinomas) and benign pleural effusions (n = 91; 31 tuberculous pleurisy, 30 parapneumonic effusion, and 30 transudate). The discriminative power of Romo1 for lung cancer-associated malignant effusion was determined using receiver operating characteristic (ROC) curve analysis and compared with those of other tumor markers. Median Romo1 level in lung cancer-associated malignant effusion was 99.3 ng/mL, which was significantly higher than that in benign pleural effusions (P < 0.001). The optimal cutoff value of Romo1 to discriminate lung cancer-associated malignant effusion from benign effusions was 67.0 ng/mL with a sensitivity of 73.8% and a specificity of 84.1%. The area under the curve was 0.837 (95% confidence interval [CI]: 0.750-0.886), which was significantly better than that of cytokeratin 19 fragments (P < 0.001). Pleural fluid Romo1 could discriminate lung cancer from benign diseases with considerable sensitivity and specificity. Our findings suggest a diagnostic potential of Romo1 for lung cancer-associated malignant effusion.

Reactive Oxygen Species Modulator 1 (Romo1) Predicts Poor Outcomes in Advanced Non-small Cell Lung Cancer Patients Treated with Platinum-Based Chemotherapy

Purpose

Reactive oxygen species modulator 1 (Romo1) is a key mediator of intracellular reactive oxygen species production. However, examination of the clinical usefulness of Romo1 in cancers has been limited. We evaluated the association of Romo1 expression with clinical outcomes in advanced non-small cell lung cancer (NSCLC) patients treated with platinum-based chemotherapy.

Materials and Methods

Romo1 expression in tumor tissue was examined by immunohistochemistry and evaluated by histological score. Survival analyses were performed according to Romo1 expression and the association between Romo1 expression and clinical parameters was evaluated.

Results

A total of 88 tumor specimens were analyzed. Significantly shorter median progression-free survival (PFS) was observed in the high Romo1 group compared with the low Romo1 group (4.5 months vs. 9.8 months, p < 0.001), and the median overall survival (OS) of the high Romo1 group was also significantly shorter than that of the low Romo1 group (8.4 months vs. 15.5 months, p < 0.001). Results of multivariate analyses showed significant association of high Romo1 expression with both poor PFS (hazard ratio [HR], 2.75; 95% confidence interval [CI], 1.71 to 4.44) and poor OS (HR, 3.99; 95% CI, 2.36 to 6.74). Results of the subgroup analysis showed a similar association regardless of tumor histology. Romo1 expression showed no association with any clinical parameter including age, sex, smoking status, stage, differentiation, or tumor histology.

Conclusion

Romo1 overexpression was associated with poor response to treatment and shorter survival in advanced NSCLC patients treated with platinum-based chemotherapy. Romo1 could be a potential adverse predictive marker in this setting.

Triticumoside induces apoptosis via caspase-dependent mitochondrial pathway and inhibits migration through downregulation of MMP2/9 in human lung cancer cells

Non-small cell lung cancer (NSCLC) is the major cancer-related death worldwide with only 14% five-year survival rate. Triticumoside, a phenolic compound present in Triticum aestivum sprout extract, has been recognized to have antiobesity and anti-inflammatory effects. However, the effect of triticumoside on cancer cell proliferation and migration has not been studied. In order to elucidate whether triticumoside exhibits an anticancer effect, cells were incubated with different doses of triticumoside, and apoptosis was assessed by observing cell viability, cellular morphological changes, and annexin-V-fluorescein isothiocyanate/propidium iodide staining. Cell cycle analysis, western blotting, wound healing assay, and quantitative-polymerase chain reaction were also performed. Triticumoside exhibited marked cytotoxicity in the cells in dose- and time-dependent manner. Triticumoside caused morphological changes, including cellular rounding, nuclear condensation, and shrinkage. Likewise, triticumoside enhanced the sub-G1 proportion of cells. Additionally, triticumoside regulated expression of apoptosis-associated proteins, such as B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X, and procaspase-3/9. Triticumoside also inhibited migration of the cells through downregulation of matrix metalloproteinase-2/9 (MMP2/9). Collectively, these results suggest that triticumoside induces apoptosis through caspase-dependent mitochondrial pathway and suppresses migration via inhibition of MMP2/9 in NSCLC A549 cells.

Reactive oxygen species modulator 1 (Romo1) overexpression is an independent predictor of poor survival in NSCLC patients who undergo surgical resection

OBJECTIVES

Reactive oxygen species modulator 1 (Romo1) is a novel protein that plays an important role in intracellular reactive oxygen species generation. Romo1 is overexpressed in most cancer cell lines and related to invasiveness and chemoresistance in vitro. However, little information is available on its clinical implications. We investigated the association between Romo1 expression and the clinical outcomes of non-small cell lung cancer (NSCLC) patients who underwent surgical resection.

MATERIALS AND METHODS

Romo1 protein expressions were evaluated immunohistochemically in resected tumor specimens. Survival analyses for overall population (n=110) and early-stage patients (n=97) were performed according to clinical parameters including level of Romo1 expression.

RESULTS

Multivariate analyses showed that high Romo1 expression in tumor tissues was significantly associated with short disease-free survival (hazard ratio [HR]=3.16, 95% confidence interval [CI]: 1.21-8.22), and with short overall survival (HR=3.22, 95% CI: 1.02-10.21). Stronger associations were observed between Romo1 expression and disease-free survival (HR=3.69, 95% CI: 1.39-9.97) and overall survival (HR=4.21, 95% CI: 1.12-14.67) in stage I and II patients than in the overall population. Romo1 expression was not associated with any clinical parameter including age, gender, smoking status, stage, differentiation, or tumor histology.

CONCLUSIONS

Increased Romo1 expression in surgically resected NSCLC was found to be significantly associated with early recurrence and poor survival. Romo1 overexpression could be a potential adverse prognostic marker in this setting.