Postoperative chemoradiotherapy with capecitabine and oxaliplatin vs.capecitabine for pathological stage N2 rectal cancer

Objective:Several studies have been conducted on the effects and toxicity of adding oxaliplatin to fluorouracilbased or capecitabine-based chemoradiotherapy(CRT)regimens as significantly increasing the toxic response without benefit to survival.In this study,we further explored the role of these two postoperative CRT regimens in patients with pathological stage N2 rectal cancer.Methods:This study was a subgroup analysis of a randomized clinical trial.A total of 180 patients with pathological stage N2 rectal cancer were eligible,85 received capecitabine with radiotherapy(RT),and 95 received capecitabine and oxaliplatin with RT.Patients in both groups received adjuvant chemotherapy[capecitabine and oxaliplatin(XELOX);or fluorouracil,leucovorin,and oxaliplatin(FOLFOX)]after CRT.Results:At a median follow-up of 59.2[interquartile range(IQR),34.0−96.8]months,the three-year diseasefree survival(DFS)was 53.3%and 64.9%in the control group and the experimental group,respectively[hazard ratio(HR),0.63;95%confidence interval(95%CI),0.41−0.98;P=0.04].There was no significant difference between the groups in overall survival(OS)(HR,0.62;95%CI,0.37−1.05;P=0.07),the incidence of locoregional recurrence(HR,0.62;95%CI,0.24−1.64;P=0.33),the incidence of distant metastasis(HR,0.67;95%CI,0.42−1.06;P=0.09)and grade 3−4 acute toxicities(P=0.78).For patients with survival longer than 3 years,the conditional overall survival(COS)was significantly better in the experimental group(HR,0.39;95%CI,0.16−0.96;P=0.03).Conclusions:Our results indicated that adding oxaliplatin to capecitabine-based postoperative CRT is safe and effective in patients with pathological stage N2 rectal cancer.

Pancreatic cancer stroma:understanding biology leads to new therapeutic strategies

Pancreatic ductal adenocarcinoma(PDA)is among the deadliest cancers in the United States and in the world.Late diagnosis,early metastasis and lack of effective therapy are among the reasons why only 6%of patients diagnosed with PDA survive past 5 years.Despite development of targeted therapy against other cancers,little progression has been made in the treatment of PDA.Therefore,there is an urgent need for the development of new treatments.However,in order to proceed with treatments,the complicated biology of PDA needs to be understood first.Interestingly,majority of the tumor volume is not made of malignant epithelial cells but of stroma.In recent years,it has become evident that there is an important interaction between the stromal compartment and the less prevalent malignant cells,leading to cancer progression.The stroma not only serves as a growth promoting source of signals but it is also a physical barrier to drug delivery.Understanding the tumor-stroma signaling leading to development of desmoplastic reaction and tumor progression can lead to the development of therapies to decrease stromal activity and improve drug delivery.In this review,we focus on how the current understanding of biology of the pancreatic tumor microenvironment can be translated into the development of targeted therapy.

Chemotherapy and its evolving role in the management of advanced prostate cancer

Advanced prostate cancer has been recognized as being responsive to androgen deprivation since the 1940s when Charles Huggins first described the role of surgical castration in managing these patients. However, androgen deprivation only results in transient disease control for the vast majority of men, with those progressing in spite of castrate testosterone levels labeled as having castrate-resistant prostate cancer （CRPC）. Until 2004, the therapeutic arena for these patients had remained stagnant, with no agent having shown a survival gain in the CRPC setting. Two landmark publications changed the prostate cancer treatment landscape by providing ＇level-1 evidence＇ that docetaxel-based chemotherapy led to prolongation in overall survival （OS）. This was followed by the approval of cabazitaxel in 2010 on the basis of Phase III data demonstrating its efficacy in patients pretreated with docetaxel. More recently, a number of next-generation androgen-directed agents （e.g. abiraterone and enzalutamide） have also been shown to lead to a survival benefit in men with CRPC. With so many new treatment options available, a number of questions remain. These include： how to best sequence chemotherapy with these newer hormonal agents, the clinical implication of cross-resistance between taxanes and androgen-directed agents and which subsets of patients may benefit most from early use of chemotherapy. This review will provide an overview of the evolving role of chemotherapy in the management of advanced prostate cancer in the current era.

Use of androgen deprivation therapy in prostate cancer： indications and prevalence

Androgens play a prominent role in the development, maintenance and progression of prostate cancer. The introduction of androgen deprivation therapies into the treatment paradigm for prostate cancer patients has resulted in a wide variety of benefits ranging from a survival advantage for those with clinically localized or locally advanced disease, to improvements in symptom control for patients with advanced disease. Controversies remain, however, surrounding the optimal timing, duration and schedule of these hormonal approaches. Newer hormonal manipulations such as abiraterone acetate have also been investigated and will broaden treatment options for men with prostate cancer, This review highlights the various androgen-directed treatment options available to men with prostate cancer, their specific indications and the evidence supporting each approach, as well as patterns of use of hormonal therapies.

Exploiting novel molecular targets in gastrointestinal cancers

Novel molecular targets are being discovered as we learn more about the aberrant processes underlying various cancers. Efforts to translate this knowledge are starting to impact on the care of patients with gastrointestinal cancers. The epidermal growth factor receptor (EGFR) pathway and angiogenesis have been targeted successfully in colorectal cancer with cetuximab, panitunumab and bevacizumab. Similarly, EGFR-targeting with erlotinib yielded significant survival benefit in pancreatic cancer when combined with gemcitabine. The multi-targeting approach with sorafenib has made it the first agent to achieve significant survival benefit in hepatocellular carcinoma. Efforts to exploit the dysregulated Akt/mTOR pathway in GI cancer therapy are ongoing. These molecular targets can be disrupted by various approaches, including the use of monoclonal antibody to intercept extracellular ligands and disrupt receptor-ligand binding, and small molecule inhibitors that interrupt the activation of intracellular kinases.

Genetic variations in colorectal cancer risk and clinical outcome

Colorectal cancer (CRC) has an apparent hereditary component, as evidenced by the well-characterized genetic syndromes and family history associated with the increased risk of this disease. However, in a large fraction of CRC cases, no known genetic syndrome or family history can be identified, suggesting the presence of “missing heritability” in CRC etiology. The genome-wide association study (GWAS) platform has led to the identification of multiple replicable common genetic variants associated with CRC risk. These newly discovered genetic variations might account for a portion of the missing heritability. Here, we summarize the recent GWASs related to newly identified genetic variants associated with CRC risk and clinical outcome. The findings from these studies suggest that there is a lack of understanding of the mechanism of many single nucleotide polymorphisms (SNPs) that are associated with CRC. In addition, the utility of SNPs as prognostic markers of CRC in clinical settings remains to be further assessed. Finally, the currently validated SNPs explain only a small fraction of total heritability in complex-trait diseases like CRC. Thus, the “missing heritability” still needs to be explored further. Future epidemiological and functional investigations of these variants will add to our understanding of CRC pathogenesis, and may ultimately lead to individualized strategies for prevention and treatment of CRC.

Albumin-linked prostate-specific antigen-activated thapsigargin- and niclosamide-based molecular grenades targeting the microenvironment in metastatic castration-resistant prostate cancer

Localized prostate cancer is curable via annihilation of the entire cancer neighborhood by surgery or local radiation.Unfortunately,once metastatic,no available therapy is curative.The vast majority will die despite aggressive systemic combinational androgenablation therapies.Thus,there is an urgent need for effective systemic therapeutics that sterilize the entire microenvironment in metastatic castration-resistant prostate cancer(mCRPC).To accomplish this goal,advantage can be taken of the unique biology of mCRPC cells.Like their normal cell of origin,mCRPCs retain expression of the prostate-specific differentiation protein,prostate-specific antigen(PSA),which they abundantly secrete into their extracellular fluid(ECF).This unique,and essentially universal,secretion of enzymatically active PSA into the ECF by mCRPCs creates an exploitable therapeutic index for activation of systemically delivered highly lipophilic toxins as“molecular grenades”covalently linked to cysteine-34 of human serum albumin(HSA)via a stable maleimide containing PSA cleavable peptide such that PSA-dependent hydrolysis(i.e.,“detonation”)releases the grenades restrictively within the ECF of mCRPC.This approach decreases dose-limiting host toxicity while enhancing plasma half-life from minutes to days(i.e.,pharmacokinetic effect)and increasing the tissue concentration of the maleimide coupled albumin delivery(MAD)in the ECF at sites of cancer due to the enhanced permeability of albumin at these sites(i.e.,enhanced permeability and retention effect).This allows the MAD-PSA detonated grenades to circulate throughout the body in a non-toxic form.Only within sites of mCRPC is there a sufficiently high level of enzymatically active PSA to efficiently“pull the pin”on the grenades releasing their lipophilic cellpenetrant toxins from HSA.Thus,if a sufficient level of“detonation”occurs,this will kill mCRPC cells,and sterilize the entire PSA-rich metastatic sites via a bystander effect.In this review,two examples of such MAD-PSA detonated molecular grenades are presenteddone based upon thapsigagin and the other on niclosamide.

Current progress and questions in germline genetics of prostate cancer

Dramatic progress has been made in the area of germline genetics of prostate cancer(PCa)in the past decade.Both common and rare genetic variants with effects on risk ranging from barely detectable to outright practice-changing have been identified.For men with high risk PCa,the application of genetic testing for inherited pathogenic mutations is becoming standard of care.A major question exists about which additional populations of men to test,as men at all risk levels can potentially benefit by knowing their unique genetic profile of germline susceptibility variants.This article will provide a brief overview of some current issues in understanding inherited susceptibility for PCa.

MicroRNA regulation network in colorectal cancer metastasis

Colorectal cancer is the third most common cancer worldwide. Metastasis is a major cause of colorectal cancer-related death. Mechanisms of metastasis remain largely obscure. MicroRNA is one of the most important epigenetic regulators by targeting mRNAs posttranscriptionally. Accumulated evidence has supported its significant role in the metastasis of colorectal cancer, including epithelial-mesenchymal transition and angiogenesis. Dissecting microRNAome potentially identifies specific microRNAs as biomarkers of colorectal cancer metastasis. Better understanding of the complex network of microRNAs in colorectal cancer metastasis provide new insights in the biological process of metastasis and in the potential targets for colorectal cancer therapies and for diagnosis of recurrent and metastatic colorectal cancer.

Advances of stereotactic body radiotherapy in pancreatic cancer

Pancreatic cancer（PCA） is one of the most aggressive tumors with few effective treatment modalities. It is the 4th and 7th leading cause of cancer death in the United States and China, respectively. At the time of diagnosis, only 20% of cases present with a resectable tumor, and about 40% with a locally advanced tumor that is considered unresectable. Even resected patients still have a poor prognosis, with an incidence of local recurrence ranging from 20% to 60%. It is also reported that up to 30% of PCA patients die from locally obstructive disease with few or no distant metastases. These findings have highlighted the importance of local radiation therapy in the treatment of PCA. As the role of conventional chemoradiotherapy remains controversial, the dawn of the pancreas stereotactic body radiation therapy（SBRT） era represents a potential paradigm shift in the management of PCA. SBRT delivers a higher biological effective dose to the tumor with sharp dose escalation in a shorter treatment time course. Pancreas SBRT is a novel therapeutic option to achieve local tumor control with minimal toxicity. Herein, we review the advancement of SBRT for PCA patients with different stages of pancreatic adenocarcinoma.

Inhibition of focal adhesion kinase enhances antitumor response of radiation therapy in pancreatic cancer through CD8+ T cells

Objective:Pancreatic ductal adenocarcinoma(PDAC)is a deadly malignancy,due in large part to its resistance to conventional therapies,including radiotherapy(RT).Despite RT exerting a modest antitumor response,it has also been shown to promote an immunosuppressive tumor microenvironment.Previous studies demonstrated that focal adhesion kinase inhibitors(FAKi)in clinical development inhibit the infiltration of suppressive myeloid cells and T regulatory(T regs)cells,and subsequently enhance effector T cell infiltration.FAK inhibitors in clinical development have not been investigated in combination with RT in preclinical murine models or clinical studies.Thus,we investigated the impact of FAK inhibition on RT,its potential as an RT sensitizer and immunomodulator in a murine model of PDAC.Methods:We used a syngeneic orthotopic murine model to study the effect of FAKi on hypofractionated RT.Results:In this study we showed that IN10018,a small molecular FAKi,enhanced antitumor response to RT.Antitumor activity of the combination of FAKi and RT is T cell dependent.FAKi in combination with RT enhanced CD8+T cell infiltration significantly in comparison to the radiation or FAKi treatment alone(P<0.05).FAKi in combination with radiation inhibited the infiltration of granulocytes but enhanced the infiltration of macrophages and T regs in comparison with the radiation or FAKi treatment alone(P<0.01).Conclusions:These results support the clinical development of FAKi as a radiosensitizer for PDAC and combining FAKi with RT to prime the tumor microenvironment of PDAC for immunotherapy.

Increased Cellular Invasion and Proliferation via Estrogen Receptor after 17-<i>β</i>-Estradiol Treatment in Breast Cancer Cells Using Stable Isotopic Labeling with Amino Acids in Cell Culture (SILAC)

17-β-estradiol (estrogen) is a steroid hormone important to human development;however, high levels of this molecule are associated with increased risk of breast cancer primarily due to estrogen’s ability to bind and activate the estrogen receptor (ER) and initiate gene transcription. Currently, estrogen mechanisms of action are classified as genomic and non-genomic and occur in an ER-dependent and ER-independent manner. In this study, we examine estrogen signaling pathways, by measuring changes in protein expression as a function of time of exposure to estrogen in both ER-positive (MCF-7) and ER-negative (MDA-MB-231) cell lines. Using a robust experimental design utilizing isotopic labeling, two-dimensional LC-MS, and bioinformatics analysis, we report genomic and non-genomic ER regulated estrogen responsive proteins. We find a little over 200 proteins differentially expressed after estrogen treatment. Cell proliferation, transcription, actin filament capping and cell to cell signaling are significantly enriched in the MCF-7 cell line alone. Translational elongation and proteolysis are enriched in both cell lines. Subsets of the proteins presented in this study are for the first time directly associated with estrogen signaling in mammary carcinoma cells. We find that estrogen affected the expression of proteins involved in numerous processes that are related to tumorigenesis such as increased cellular division and invasion in an ER-dependent manner. Moreover, we identified negative regulation of apoptosis as a non-genomic process of estrogen. This study complements gene expression studies and highlights the need for both genomic and proteomic analyses in unraveling the complex mechanisms by which estrogen affects progression of breast cancer.

Brain Metastases in Patients with Gynecologic Cancers: A Single Institution Experience and Review of the Literature

Objective: Brain Metastasis (BM) from primary gynecologic cancers is a rare entity. The advances and successes in the treatment of primary gynecologic malignancies, have led to prolonged survival and, a higher incidence of BM. This study aims to report the experience at our institution in managing these patients, and provide possible data points that may be essential to note as prognostic factors, and see if our findings are consistent with the literature in this subject. We also aim to provide a brief literature review of patients with gynecologic cancers and BM. Methods: This is a small single institution retrospective study of 23 patients with a gynecologic malignancy and BM, identified between the years 2007-2015. Data were collected on variables including patient demographics, disease and treatment. Results: The median overall survival from the primary diagnosis was 28 months. Median time from diagnosis of BM to death was 9 months. Conclusion: The outcomes in our study are similar to what is stated in the current literature with regard to BM from gynecologic malignancies. Our literature search also revealed that the molecular analysis and treatment of the primary tumor remain important to prevent BMs. The tendency of tumors to metastasize varies for one tumor type to another for the same type of tumor. The tendency to develop BM may not only depend on risk factors such as stage, grade, and histology, but also on the genetic profile of the primary tumor. The study suggests that multimodal treatment of BM has better outcomes in managing BM from gynecologic cancers.

Long and noncoding RNAs （Inc-RNAs） determine androgen receptor dependent gene expression in prostate cancer growth in vivo

Hyperactive androgen receptor （AR） activity remains a key determinant of the onset and progression of prostate cancer and resistance to current therapies. The mechanisms governing castrate resistant prostate cancer are poorly understood, but defining these molecular events is essential in order to impact deaths from prostate cancer.

Gene therapy of cancer

The essence of gene therapy is to placefunctioning genes into a patient’s cells for therapeuticpurposes. Gene therapy may be employed to ①enhance anti-tumor immune responses; ②

Effective cellular vaccines generated by in vitro or in vivo modification of tumor cells using gene transfer approaches for cancer immunogene therapy

Tumor cells escape host immune surveillance bydown-regulation of MHC and/or co-stimulatorymolecules.Anti-tumor immune responses are mediated primarily by T cells.A deficiency in either MHC or co-stimulatory molecules on tumor cells is associated with a failure to induce anti-tumor immunity.

Combining active immunotherapy with immune checkpoint blockade for the treatment of advanced prostate cancer

Combination immunotherapy is emerging as a promising approach for the treatment of advanced prostate cancer. This research highlight discusses the combination of a PSA-directed pox-viral vaccine and a monoclonal antibody blocking an important immune checkpoint molecule to treat men with metastatic castration- resistant prostate cancer. The results demonstrate feasibility and safety, as well as intriguing clinical responses to this combination therapy.

Alternative polyadenylation:An untapped source for prostate cancer biomarkers and therapeutic targets?

Objective:To review alternative polyadenylation(APA)as a mechanism of gene regulation and consider potential roles for APA in prostate cancer(PCa)biology and treatment.Methods:An extensive review of mRNA polyadenylation,APA,and PCa literature was performed.This review article introduces APA and its association with human disease,outlines the mechanisms and components of APA,reviews APA in cancer biology,and considers whether APA may contribute to PCa progression and/or produce novel biomarkers and therapeutic targets for PCa.Results:Eukaryotic mRNA 30-end cleavage and polyadenylation play a critical role in gene expression.Most human genes encode more than one polyadenylation signal,and produce more than one transcript isoform,through APA.Polyadenylation can occur throughout the gene body to generate transcripts with differing 30-termini and coding sequence.Differences in 30-untranslated regions length can modify post-transcriptional gene regulation by microRNAs and RNA binding proteins,and alter mRNA stability,translation efficiency,and subcellular localization.Distinctive APA patterns are associated with human diseases,tissue origins,and changes in cellular proliferation rate and differentiation state.APA events may therefore generate unique mRNA biomarkers or therapeutic targets in certain cancer types or phenotypic states.Conclusions:The full extent of cancer-associated and tissue-specific APA events have yet to be defined,and the mechanisms and functional consequences of APA in cancer remain incompletely understood.There is evidence that APA is active in PCa,and that it may be an untapped resource for PCa biomarkers or therapeutic targets.

Race and colorectal cancer screening compliance among persons with a family history of cancer

AIM: To determine compliance to colorectal cancer(CRC) screening guidelines among persons with a family history of any type of cancer and investigate racial differences in screening compliance.METHODS: We used the 2007 Health Information National Trends Survey and identified 1094(27.4%)respondents(weighted population size = 21959672) without a family history of cancer and 3138(72.6%) respondents(weighted population size = 58201479) with a family history of cancer who were 50 years and older. We defined compliance with CRC screening as the use of fecal occult blood testing within 1 year, sigmoidoscopy within 5 years, or colonoscopy within 10 years. We compared compliance with CRC screening among those with and without a family member with a history of cancer. RESULTS: Overall, those with a family member with cancer were more likely to be compliant with CRC screening(64.9% vs 55.1%; OR = 1.45; 95%CI: 1.20-1.74). The absolute increase in screening rates associated with family history of cancer was 8.2% among whites. Hispanics had lowest screening rates among those without family history of cancer 41.9% but had highest absolute increase(14.7%) in CRC screening rate when they have a family member with cancer. Blacks had the lowest absolute increase in CRC screening(5.3%) when a family member has a known history of cancer. However, the noted increase in screening rates among blacks and Hispanics when they have a family member with cancer were not higher than whites without a family history of cancer:(54.5% vs 58.7%; OR = 1.16; 95%CI: 0.72-1.88) for blacks and(56.7% vs 58.7%; OR = 1.25; 95%CI: 0.72-2.18) for Hispanics.CONCLUSION: While adults with a family history of any cancer were more likely to be compliant with CRC screening guidelines irrespective of race/ethnicity, blacks and Hispanics with a family history of cancer were less likely to be compliant than whites without a family history. Increased burden from CRC among blacks may be related to poor uptake of screening among high-risk groups.

Prostate cancer biomarker： a key field to explore

In order to achieve personalized cancer care, tools are needed to predict benefitfrom a specific therapy. Prostate cancer bio- marker study is a key field to explore so that the natural course of a patient＇s disease can be predicted. A panel of inflammation/ immune-related and prostate cancer-related genes was screened by Ross et al. to assess genes predictive of castration-resistant pro- state cancer （CRPC） survival. They found that a six-gene model was superior to tm- ditionaUy used clinic-pathological variables. Although the clinic utility of this model remains to be determined, the blood based technical achievement and potential may eventually improve personalized cancer care.