Current Molecular and Genetic Aspects of Pancreatic Cancer, the Role of Metastasis Associated Proteins (MTA): A Review

Expression and Significance of MTA2 and CPNE1 in Cervical Squamous Cell Carcinoma

The aim of this study was to investigate the expression and clinical significance of MTA2 and CPNE1 proteins in cervical squamous cell carcinoma. In this study, high-risk human papillomavirus (HPV) typing was performed on cervical cancer tissues. Reverse transcription polymerase chain reaction and immunochemical EliVision method were used to examine the expressions of MTA2 and CPNE1 in the cervix, and their relationship with clinicopathologic features. We found that it is mainly distributed in these types, namely HPV-16 (23.8%), HPV-18 (20.9%), HPV-53 (17.1%), HPV-52 (15.5%), HPV-82 (11.7%), HPV-56 (10.8%). The expressions of MTA2 and CPNE1 in cervical squamous cell carcinoma tissues were significantly higher than those in normal tissues ( P <0.01). The expressions of MTA2 and CPNE1 were correlated with FIGO stage, degree of differentiation, and lymph node metastasis of cervical cancer ( P <0.05), but not with the patient's age ( P >0.05). The rank correlation coefficient of MTA2 and CPNE1 protein expression in cervical squamous cell carcinoma was 0.668 ( P <0.01), and the 2 expressions were positively correlated. MTA2 and CPNE1 are closely related to the occurrence and development of cervical squamous cell carcinoma and may play a synergistic role in the evolution of cervical squamous cell carcinoma.

The Advances in Epigenetics for Cancer Radiotherapy

Cancer is an important factor threatening human life and health; in recent years, its morbidity and mortality remain high and demosntrate an upward trend. It is of great significance to study its pathogenesis and targeted therapy. As the complex mechanisms of epigenetic modification has been increasingly discovered, they are more closely related to the occurrence and development of cancer. As a reversible response, epigenetic modification is of great significance for the improvement of classical therapeutic measures and the discovery of new therapeutic targets. It has become a research focusto explore the multi-level mechanisms of RNA, DNA, chromatin and proteins. As an important means of cancer treatment, radiotherapy has made great progress in technology, methods, means and targeted sensitization after years of rapid development, and even research on radiotherapy based on epigenetic modification is rampant. A series of epigenetic effects of radiation on DNA methylation, histone modification, chromosome remodeling, RNA modification and non-coding RNA during radiotherapy affects the therapeutic effects and prognosis. Starting from the epigenetic mechanism of tumorigenesis, this paper reviews the latest progress in the mechanism of interaction between epigenetic modification and cancer radiotherapy and briefly introduces the main types, mechanisms and applications of epigenetic modifiers used for radiotherapy sensitization in order to explore a more individual and dynamic approach of cancer treatment based on epigenetic mechanism. This study strives to make a modest contribution to the progress of human disease research.

Radiomics nomogram for the preoperative prediction of lymph node metastasis in pancreatic ductal adenocarcinoma

PURPOSE

To develop and validate a radiomics nomogram for the preoperative prediction of lymph node (LN) metastasis in pancreatic ductal adenocarcinoma (PDAC).

MATERIALS AND METHODS

In this retrospective study, 225 patients with surgically resected, pathologically confirmed PDAC underwent multislice computed tomography (MSCT) between January 2014 and January 2017. Radiomics features were extracted from arterial CT scans. The least absolute shrinkage and selection operator method was used to select the features. Multivariable logistic regression analysis was used to develop the predictive model, and a radiomics nomogram was built and internally validated in 45 consecutive patients with PDAC between February 2017 and December 2017. The performance of the nomogram was assessed in the training and validation cohort. Finally, the clinical usefulness of the nomogram was estimated using decision curve analysis (DCA).

RESULTS

The radiomics signature, which consisted of 13 selected features of the arterial phase, was significantly associated with LN status (p < 0.05) in both the training and validation cohorts. The multivariable logistic regression model included the radiomics signature and CT-reported LN status. The individualized prediction nomogram showed good discrimination in the training cohort [area under the curve (AUC), 0.75; 95% confidence interval (CI), 0.68-0.82] and in the validation cohort (AUC, 0.81; 95% CI, 0.69-0.94) and good calibration. DCA demonstrated that the radiomics nomogram was clinically useful.

CONCLUSIONS

The presented radiomics nomogram that incorporates the radiomics signature and CT-reported LN status is a noninvasive, preoperative prediction tool with favorable predictive accuracy for LN metastasis in patients with PDAC.

Effect of the transcription factor YY1 on the development of pancreatic endocrine and exocrine tumors: a narrative review

Pancreatic tumors are classified into endocrine and exocrine types, and the clinical manifestations in patients are nonspecific. Most patients, especially those with pancreatic ductal adenocarcinoma (PDAC), have lost the opportunity to receive for the best treatment at the time of diagnosis. Although chemotherapy and radiotherapy have shown good therapeutic results in other tumors, their therapeutic effects on pancreatic tumors are minimal. A multifunctional transcription factor, Yin-Yang 1 (YY1) regulates the transcription of a variety of important genes and plays a significant role in diverse tumors. Studies have shown that targeting YY1 can improve the survival time of patients with tumors. In this review, we focused on the mechanism by which YY1 affects the occurrence and development of pancreatic tumors. We found that a YY1 mutation is specific for insulinomas and has a role in driving the degree of malignancy. In addition, changes in the circadian network are a key causative factor of PDAC. YY1 promotes pancreatic clock progression and induces malignant changes, but YY1 seems to act as a tumor suppressor in PDAC and affects many biological behaviors, such as proliferation, migration, apoptosis and metastasis. Our review summarizes the progress in understanding the role of YY1 in pancreatic endocrine and exocrine tumors and provides a reasonable assessment of the potential for therapeutic targeting of YY1 in pancreatic tumors.

Metastasis-associated protein 2 regulates human hepatocellular carcinoma metastasis progression through modulating p38MAPK/MMP2 pathways

Studies have shown the overexpression of metastasis-associated protein 2 (MTA2) to be associated with hepatocellular carcinoma (HCC) progression. However, the molecular mechanism of MTA2 expression in HCC is unclear. In our study, we found a higher level of MTA2 in HCC tissues than in normal tissues and a significant correlation between tumor grade and overall survival of HCC patients. We also found that MTA2 inhibition reduced the migration and invasion capabilities of HCC cells, independent of cell proliferation. Mechanistic studies have suggested that MTA2 protein and mRNA are more highly expressed in SK-Hep-1 and Huh-7 cells compared with other HCC cells. MTA2 silencing drastically reduced migration and invasion capability and also inhibited matrix metalloproteinase 2 (MMP2) at the transcriptional and translation levels in both cells. In addition, treatment with the MMP2 antibody markedly impaired MTA2-knockdown-mediated inhibition of migration and invasion in SK-Hep-1 cells. Furthermore, MTA2 knockdown reduced the phosphorylation of the p38MAPK protein, whereas the inhibition of p38MAPK (SB203580 or si-p38) confirmed that blocking the p38MAPK pathway mediated MTA2-knockdown-inhibited migration and invasion in SK-Hep-1 cells. We demonstrated the molecular mechanism by which MTA2 inhibits human HCC cell metastasis through the p38MAPK/MMP2 pathways, which might be helpful in determining the diagnostic value of this protein in patients with HCC

Evolving trends in pancreatic cancer therapeutic development

Despite advances in translational research, the overall 5-year survival for pancreatic cancer remains dismal and with rising incidence pancreatic cancer is predicted to be the second leading cause of cancer death for many developed countries. Surgical intervention followed by cytotoxic chemotherapy are currently the best options for treatment, but disease recurrence is very common. Efforts to develop new therapeutic agents and delivery systems are necessary to achieve better clinical efficacy with less toxicity. Promising prospects are arising with new preclinical and clinical therapeutic strategies using small molecule targeted therapies, RNAi, stromal therapies, and immunotherapies. With a better understanding of the biology to aid target selection and discovery of biomarkers to aid precision medicine, better opportunities will evolve to shape the therapeutic landscape, enhance patient quality of life and increase overall survival.

Survival and Clinicopathological Significance of SIRT1 Expression in Cancers: A Meta-Analysis

Background: Silent information regulator 2 homolog 1 (SIRT1) is an evolutionarily conserved enzymes with nicotinamide adenine dinucleotide (NAD)⁺-dependent deacetylase activity. SIRT1 is involved in a large variety of cellular processes, such as genomic stability, energy metabolism, senescence, gene transcription, and oxidative stress. SIRT1 has long been recognized as both a tumor promoter and tumor suppressor. Its prognostic role in cancers remains controversial. Methods: A meta-analysis of 13,138 subjects in 63 articles from PubMed, EMBASE, and Cochrane Library was performed to evaluate survival and clinicopathological significance of SIRT1 expression in various cancers. Results: The pooled results of meta-analysis showed that elevated expression of SIRT1 implies a poor overall survival (OS) of cancer patients [Hazard Ratio (HR) = 1.566, 95% CI: 1.293-1.895, P < 0.0001], disease free survival (DFS) (HR = 1.631, 95% CI: 1.250-2.130, P = 0.0003), event free survival (EFS) (HR = 2.534, 95% CI: 1.602-4.009, P = 0.0001), and progress-free survival (PFS) (HR = 3.325 95% CI: 2.762-4.003, P < 0.0001). Elevated SIRT1 level was associated with tumor stage [Relative Risk (RR) = 1.299, 95% CI: 1.114-1.514, P = 0.0008], lymph node metastasis (RR = 1.172, 95% CI: 1.010-1.360, P = 0.0363), and distant metastasis (RR = 1.562, 95% CI: 1.022-2.387, P = 0.0392). Meta-regression and subgroup analysis revealed that ethnic background has influence on the role of SIRT1 expression in predicting survival and clinicopathological characteristics of cancers. Overexpression of SIRT1 predicted a worse OS and higher TNM stage and lymphatic metastasis in Asian population especially in China. Conclusion: Our data suggested that elevated expression of SIRT1 predicted a poor OS, DFS, EFS, PFS, but not for recurrence-free survival (RFS) and cancer-specific survival (CCS). SIRT1 overexpression was associated with higher tumor stage, lymph node metastasis, and distant metastasis. SIRT1-mediated molecular events and biological processes could be an underlying mechanism for metastasis and SIRT1 is a therapeutic target for inhibiting metastasis, leading to good prognosis.

HLA-A2-Restricted Epitopes Identified from MTA1 Could Elicit Antigen-Specific Cytotoxic T Lymphocyte Response

Overexpression of metastasis-associated protein 1 (MTA1) has been observed in many human malignancies and is significantly related to tumor invasion and metastasis, therapeutic resistance to radiation and chemotherapy, making MTA1 an ideal candidate tumor antigen. We identified several human leukocyte antigen- (HLA-) A2-restricted epitopes in MTA1 and evaluated their binding ability to HLA-A∗0201 molecules. Subsequently, a recombinant fragment encompassing the dominant epitopes, MTA1(1-283), was expressed, and the abilities of the selected epitopes of MTA1 and the MTA1(1-283) fragment to induce cytotoxic T lymphocytes (CTLs) were examined. Our results indicated that the epitopes and MTA1(1-283) fragment elicited HLA-A2-restricted and antigen-specific CTL responses both in vitro and in vivo. The new epitopes identified here may help promote the development of new therapeutic vaccines for HLA-A2+ patients expressing MTA1.