Effects of Zoledronate on Cancer, Cardiac Events, and Mortality in Osteopenic Older Women

We recently showed that zoledronate prevented fractures in older women with osteopenia (hip T-scores between -1.0 and -2.5). In addition to fewer fractures, this study also suggested that women randomized to zoledronate had fewer vascular events, a lower incidence of cancer, and a trend to lower mortality. The present analysis provides a more detailed presentation of the adverse event data from that study, a 6-year, double-blind trial of 2000 women aged >65 years recruited using electoral rolls. They were randomly assigned to receive four infusions of either zoledronate 5 mg or normal saline at 18-month intervals. Supplements of vitamin D, but not calcium, were provided. There were 1017 serious adverse events in 443 participants in the placebo group, and 820 events in 400 participants in those randomized to zoledronate (relative risk = 0.90; 95% CI, 0.81 to 1.00). These events included fractures resulting in hospital admission. Myocardial infarction occurred in 39 women (43 events) in the placebo group and in 24 women (25 events) in the zoledronate group (hazard ratio 0.60 [95% CI, 0.36 to 1.00]; rate ratio 0.58 [95% CI, 0.35 to 0.94]). For a prespecified composite cardiovascular endpoint (sudden death, myocardial infarction, coronary artery revascularization, or stroke) 69 women had 98 events in the placebo group, and 53 women had 71 events in the zoledronate group (hazard ratio 0.76 [95% CI, 0.53 to 1.08]; rate ratio 0.72 [95% CI, 0.53 to 0.98]). Total cancers were significantly reduced with zoledronate (hazard ratio 0.67 [95% CI, 0.51 to 0.89]; rate ratio 0.68 [95% CI, 0.52 to 0.89]), and this was significant for both breast cancers and for non-breast cancers. Eleven women had recurrent or second breast cancers during the study, all in the placebo group. The hazard ratio for death was 0.65 (95% CI, 0.40 to 1.06; p = 0.08), and 0.51 (95% CI, 0.30 to 0.87) in those without incident fragility fracture. These apparent beneficial effects justify further appropriately powered trials of zoledronate with these nonskeletal conditions as primary endpoints. © 2019 American Society for Bone and Mineral Research.

Primary Bone Tumors: Challenges and Opportunities for CAR-T Therapies

Primary malignant bone tumors are rare, occur in all age groups, and include distinct entities such as osteosarcoma, Ewing sarcoma, and chondrosarcoma. Traditional treatment with some combination of chemotherapy, surgery, and radiation has reached the limit of efficacy, with substantial room for improvement in patient outcome. Furthermore, genomic characterization of these tumors reveals a paucity of actionable molecular targets. Against this backdrop, recent advances in cancer immunotherapy represent a silver lining in the treatment of primary bone cancer. Major strategies in cancer immunotherapy include stimulating naturally occurring anti-tumor T cells and adoptive transfer of tumor-specific cytotoxic T cells. Chimeric antigen receptor T cells (CAR-T cells) belong to the latter strategy and are an impressive application of both insights into T cell biology and advances in genetic engineering. In this review, we briefly describe the CAR-T approach and discuss its applications in primary bone tumors. © 2019 American Society for Bone and Mineral Research.

Risk of Cancer in 767 Patients with Giant Cell Arteritis in Western Norway: A Retrospective Cohort with Matched Controls

OBJECTIVE

To determine the risk of cancer in a large Norwegian cohort of patients with giant cell arteritis (GCA).

METHODS

This is a hospital-based, retrospective, observational cohort study including patients diagnosed with GCA in the Bergen Health Area during 1972-2012. Patients were identified through computerized hospital records using the International Classification of Diseases coding system. Medical records were reviewed. Each patient was randomly assigned population controls matched on age, sex, and geography from the Central Population Registry of Norway. Data on the occurrence of cancer were obtained from the Cancer Registry of Norway. The cumulative risk of malignancy was estimated using Kaplan-Meier methods and potential differences were analyzed using the Gehan-Breslow and log-rank tests.

RESULTS

We identified 881 cases with a clinical diagnosis of GCA, of which 792 fulfilled the American College of Rheumatology (ACR) 1990 classification criteria and 528 were biopsy-verified. Cases with no registered cancer prior to GCA diagnosis were included in a time-to-event analysis, with first cancer as the event (n = 767 with clinical GCA diagnosis, 686 fulfilling ACR criteria for GCA, 463 biopsy-verified). These cases were matched with previously cancer-free population controls (n = 1437, 1284, 895, respectively). We found no significant difference in the risk of malignancy after time of diagnosis/matching for GCA patients compared to population controls (p > 0.05).

CONCLUSION

In this study of a large and well-characterized cohort of patients with GCA, there was no difference in the risk of malignancy in patients with GCA compared to matched population controls.

Cancer- and Chemotherapy-Induced Musculoskeletal Degradation

Mobility in advanced cancer patients is a major health care concern and is often lost in advanced metastatic cancers. Erosion of mobility is a major component in determining quality of life but also starts a process of loss of muscle and bone mass that further devastates patients. In addition, treatment options become limited in these advanced cancer patients. Loss of bone and muscle occurs concomitantly. Advanced cancers that are metastatic to bone often lead to bone loss (osteolytic lesions) but may also lead to abnormal deposition of new bone (osteoblastic lesions). However, in both cases there is a disruption to normal bone remodeling and radiologic evidence of bone loss. Many antitumor therapies can also lead to loss of bone in cancer survivors. Bone loss releases cytokines (TGFβ) stored in the mineralized matrix that can act on skeletal muscle and lead to weakness. Likewise, loss of skeletal muscle mass leads to reduced bone mass and quality via mechanical and endocrine signals. Collectively these interactions are termed bone-muscle cross-talk, which has garnered much attention recently as a prime target for musculoskeletal health. Pharmacological approaches as well as nutrition and exercise can improve muscle and bone but have fallen short in the context of advanced cancers and cachexia. This review highlights our current knowledge of these interventions and discusses the difficulties in treating severe musculoskeletal deficits with the emphasis on improving not only bone mass and muscle size but also functional outcomes. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

The Emerging Role of Osteocytes in Cancer in Bone

Advances in the last decade have established the osteocyte, the most abundant cell in bone, as a dynamic and multifunctional cell capable of controlling bone homeostasis by regulating the function of both osteoblasts and osteoclasts. In addition, accumulating evidence demonstrates that osteocyte function is altered in several skeletal disorders, and targeting osteocytes and their derived factors improves skeletal health. Despite the remarkable progress in our understanding of osteocyte biology, there has been a paucity of information regarding the role of osteocytes in the progression of cancer in bone. Exciting, recent discoveries suggest that tumor cells communicate with osteocytes to generate a microenvironment that supports the growth and survival of cancer cells and stimulates bone destruction. This review features these novel findings and discussions regarding the impact of chemotherapy on osteocyte function and the potential of targeting osteocytes for the treatment of cancer in bone. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

Scoliosis in Fibrous Dysplasia/McCune-Albright Syndrome: Factors Associated With Curve Progression and Effects of Bisphosphonates

Scoliosis is a complication of fibrous dysplasia/McCune-Albright syndrome (FD/MAS); however, risk factors and long-term outcomes are unknown. Bisphosphonates are commonly used; however, it is unknown whether their use decrease the risk of progressive scoliosis. Clinical data from the National Institutes of Health (NIH) cohort study was reviewed. Cobb angles were measured, and variables associated with scoliosis progression were identified. Of 138 subjects with available radiographs, 84 (61%) had scoliosis, including 55 (65%) classified as mild (Cobb angle >10 to ≤30 degrees), 11 (13%) as moderate (>30 to ≤45 degrees), and 18 (22%) as severe (>45 degrees). Total skeletal disease burden was highly associated with scoliosis severity (p < 0.0001). Endocrinopathies associated with scoliosis included fibroblast growth factor 23 (FGF23)-mediated hypophosphatemia (p < 0.001) and hyperthyroidism (p < 0.001). Bone turnover markers, including osteocalcin and NTX-telopeptides, were associated with severe scoliosis (p < 0.01). Associations were identified between Cobb angle and functional metrics, including leg length discrepancy (p < 0.01), hip range of motion (p < 0.05), and strength of the gluteus medius and maximus (p < 0.01). Longitudinal analyses were conducted in 69 subjects who had serial radiographs over a median 4.9-year period (range, 0.9 to 14.7 years). Twenty-two subjects were treated with bisphosphonates; there was no difference in Cobb angle progression compared to untreated subjects (0.10 versus 0.53 degrees/year, p = 0.36). Longitudinal data was available for 10 of 12 subjects treated with spinal fusion; one had instrumentation failure, but in nine subjects Cobb angles were stable with 6.1 years of follow-up (range, 0.9 to 14.7 years). Two fatalities from scoliosis-associated restrictive lung disease occurred in subjects managed non-operatively. Scoliosis occurs frequently in patients with polyostotic FD, and may be potentially fatal. The primary risk factor for progressive scoliosis is total skeletal disease burden. Treatable features that contribute to scoliosis progression include leg length discrepancy, FGF23-mediated hypophosphatemia, and hyperthyroidism. Current data do not support routine use of bisphosphonates to prevent progression of spinal curvature. Spinal fusion is frequently effective in providing long-term stability, and may be lifesaving. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

Optimizing the utility of the ARC Framework

This commentary concerns the Affect Regulation in Cancer Framework, which synthesizes theoretical perspectives and empirical evidence on emotion regulation and coping to posit that flexible use of a suite of strategies can result in optimal Affect Regulation in Cancer. The framework raises a number of questions that should be answered for it to reach its full potential. Here, I extend this framework by suggesting (1) outcomes to define adaptive regulation; (2) examples of research questions and hypotheses; (3) intervention development research; and (4) additional cancer contexts to which the framework should be applied.

An evidence-based treatment algorithm for colorectal polyp cancers: results from the Scottish Screen-detected Polyp Cancer Study (SSPoCS)

OBJECTIVES

Colorectal polyp cancers present clinicians with a treatment dilemma. Decisions regarding whether to offer segmental resection or endoscopic surveillance are often taken without reference to good quality evidence. The aim of this study was to develop a treatment algorithm for patients with screen-detected polyp cancers.

DESIGN

This national cohort study included all patients with a polyp cancer identified through the Scottish Bowel Screening Programme between 2000 and 2012. Multivariate regression analysis was used to assess the impact of clinical, endoscopic and pathological variables on the rate of adverse events (residual tumour in patients undergoing segmental resection or cancer-related death or disease recurrence in any patient). These data were used to develop a clinically relevant treatment algorithm.

RESULTS

485 patients with polyp cancers were included. 186/485 (38%) underwent segmental resection and residual tumour was identified in 41/186 (22%). The only factor associated with an increased risk of residual tumour in the bowel wall was incomplete excision of the original polyp (OR 5.61, p=0.001), while only lymphovascular invasion was associated with an increased risk of lymph node metastases (OR 5.95, p=0.002). When patients undergoing segmental resection or endoscopic surveillance were considered together, the risk of adverse events was significantly higher in patients with incomplete excision (OR 10.23, p<0.001) or lymphovascular invasion (OR 2.65, p=0.023).

CONCLUSION

A policy of surveillance is adequate for the majority of patients with screen-detected colorectal polyp cancers. Consideration of segmental resection should be reserved for those with incomplete excision or evidence of lymphovascular invasion.

All-cause and cancer-specific mortality in GORD in a population-based cohort study (the HUNT study)

OBJECTIVE

Gastro-oesophageal reflux is a public health concern which could have associated oesophageal complications, including adenocarcinoma, and possibly also head-and-neck and lung cancers. The aim of this study was to test the hypothesis that reflux increases all-cause and cancer-specific mortalities in an unselected cohort.

DESIGN

The Nord-Trøndelag health study (HUNT), a Norwegian population-based cohort study, was used to identify individuals with and without reflux in 1995-1997 and 2006-2008, with follow-up until 2014. All-cause mortality and cancer-specific mortality were assessed from the Norwegian Cause of Death Registry and Cancer Registry. Multivariable Cox regression was used to calculate HRs with 95% CIs for mortality with adjustments for potential confounders.

RESULTS

We included 4758 participants with severe reflux symptoms and 51 381 participants without reflux symptoms, contributing 60 323 and 747 239 person-years at risk, respectively. Severe reflux was not associated with all-cause mortality, overall cancer-specific mortality or mortality in cancer of the head-and-neck or lung. However, for men with severe reflux a sixfold increase in oesophageal adenocarcinoma-specific mortality was found (HR 6.09, 95% CI 2.33 to 15.93) and the mortality rate was 0.27 per 1000 person-years. For women, the corresponding mortality was not significantly increased (HR 3.68, 95% CI 0.88 to 15.27) and the mortality rate was 0.05 per 1000 person-years.

CONCLUSIONS

Individuals with severe reflux symptoms do not seem to have increased all-cause mortality or overall cancer-specific mortality. Although the absolute risk is small, individuals with severe reflux symptoms have a clearly increased oesophageal adenocarcinoma-specific mortality.

Octreotide Is Ineffective in Treating Tumor-Induced Osteomalacia: Results of a Short-Term Therapy

Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome in which unregulated hypersecretion of fibroblast growth factor 23 (FGF23) by phosphaturic mesenchymal tumors (PMT) causes renal phosphate wasting, hypophosphatemia, and osteomalacia. The resulting mineral homeostasis abnormalities and skeletal manifestations can be reversed with surgical resection of the tumor. Unfortunately, PMTs are often difficult to locate, and medical treatment with oral phosphate and vitamin D analogues is either insufficient to manage the disease or not tolerated. Octreotide has been proposed as a potential treatment for TIO due to the presence of somatostatin receptors (SSTR) on PMTs; however, the role of somatostatin signaling in PMTs and the efficacy of treatment of TIOs with somatostatin analogues is not clear. In an effort to evaluate the efficacy of octreotide therapy in TIO, five subjects with TIO were treated with octreotide for 3 days. Blood intact FGF23, phosphate, and 1,25(OH)₂ D₃ , and tubular reabsorption of phosphate (TRP) were measured at frequent time points during treatment. Octreotide's effects were assessed by comparing group means of the biochemical parameters at each time-point to mean baseline values. There were no significant changes in blood phosphate, FGF23, 1,25(OH)₂ D₃ , or TRP during octreotide treatment, consistent with a lack of efficacy of octreotide in treating TIO. © 2017 American Society for Bone and Mineral Research.

Malignancy in Pediatric-onset Systemic Lupus Erythematosus

OBJECTIVE

To determine cancer incidence in a large pediatric-onset systemic lupus erythematosus (SLE) population.

METHODS

Data were examined from 12 pediatric SLE registries in North America. Patients were linked to their regional cancer registries to detect cancers observed after cohort entry, defined as date first seen in the clinic. The expected number of malignancies was obtained by multiplying the person-years in the cohort (defined from cohort entry to end of followup) by the geographically matched age-, sex-, and calendar year-specific cancer rates. The standardized incidence ratio (SIR; ratio of cancers observed to expected) was generated, with 95% CI.

RESULTS

A total of 1168 patients were identified from the registries. The mean age at cohort entry was 13 years (SD 3.3), and 83.7% of the subjects were female. The mean duration of followup was 7.6 years, resulting in a total observation period of 8839 years spanning the calendar period 1974-2009. During followup, fourteen invasive cancers occurred (1.6 cancers per 1000 person-yrs, SIR 4.13, 95% CI 2.26-6.93). Three of these were hematologic (all lymphomas), resulting in an SIR for hematologic cancers of 4.68 (95% CI 0.96-13.67). SIR were increased for both male and female patients, and across age groups.

CONCLUSION

Although cancer remains a relatively rare outcome in pediatric-onset SLE, our data do suggest an increase in cancer for patients followed an average of 7.6 years. About one-fifth of the cancers were hematologic. Longer followup, and study of drug effects and disease activity, is warranted.

Targeting super-enhancer-associated oncogenes in oesophageal squamous cell carcinoma

OBJECTIVES

Oesophageal squamous cell carcinoma (OSCC) is an aggressive malignancy and the major histological subtype of oesophageal cancer. Although recent large-scale genomic analysis has improved the description of the genetic abnormalities of OSCC, few targetable genomic lesions have been identified, and no molecular therapy is available. This study aims to identify druggable candidates in this tumour.

DESIGN

High-throughput small-molecule inhibitor screening was performed to identify potent anti-OSCC compounds. Whole-transcriptome sequencing (RNA-Seq) and chromatin immunoprecipitation sequencing (ChIP-Seq) were conducted to decipher the mechanisms of action of CDK7 inhibition in OSCC. A variety of in vitro and in vivo cellular assays were performed to determine the effects of candidate genes on OSCC malignant phenotypes.

RESULTS

The unbiased high-throughput small-molecule inhibitor screening led us to discover a highly potent anti-OSCC compound, THZ1, a specific CDK7 inhibitor. RNA-Seq revealed that low-dose THZ1 treatment caused selective inhibition of a number of oncogenic transcripts. Notably, further characterisation of the genomic features of these THZ1-sensitive transcripts demonstrated that they were frequently associated with super-enhancer (SE). Moreover, SE analysis alone uncovered many OSCC lineage-specific master regulators. Finally, integrative analysis of both THZ1-sensitive and SE-associated transcripts identified a number of novel OSCC oncogenes, including PAK4, RUNX1, DNAJB1, SREBF2 and YAP1, with PAK4 being a potential druggable kinase.

CONCLUSIONS

Our integrative approaches led to a catalogue of SE-associated master regulators and oncogenic transcripts, which may significantly promote both the understanding of OSCC biology and the development of more innovative therapies.

Improvement of Giant Cell Lesions of the Jaw Treated With High and Low Doses of Denosumab: A Case Series

Giant cell tumors (GCTs) and central giant cell granulomas (CGCGs) are aggressive lesions that appear in the jaw. These lesions occur in the second and third decades of life and often arise in the mandible. Clinical manifestations of these lesions vary from asymptomatic to symptomatic tooth displacement with cortical perforation. GCTs, which are characterized by multinucleated osteoclast-type giant cells that express receptor activator of nuclear factor-κB (RANK) ligand, rarely present in the jaw and have overlapping histopathologic features with CGCGs, which are composed of fibroblastic stromal cell lesions. GCTs and CGCGs have overlying histopathologic features that make distinction between the two challenging. There is a real controversy as to whether giant cell tumors and central giant cell granulomas are in fact, one and the same lesion. The majority of GCTs occur in the long bone, with surgery being the typical therapeutic option. Denosumab as a treatment modality is a fairly new concept that has been used effectively in GCTs affecting long bones. There is less experience, however, with its use for jaw lesions. This seven-case series describes the effective use of both low-dose and high-dose denosumab in the treatment of GCTs and CGCGs affecting the jaw and special dosing considerations for younger patients who present with disease. © 2017 The Authors. JBMR Plus Published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.

The Application of CRISPR/Cas Technology to Efficiently Model Complex Cancer Genomes in Stem Cells

CRISPR/Cas gene editing technologies have emerged as powerful tools in the study of oncogenic transformation. The system's specificity, versatility, and ease of implementation allow researchers to identify important molecular markers and pathways which grant cancers stem cell like properties. This technology has already been applied to researching specific cancers, but has seen restricted therapeutic applications due to inherent ethical and technical limitations. Active development and adaptation of the CRISPR/Cas system has produced new methods to take advantage of both non-homologous end joining and homologous recombination repair mechanisms in attempts to remedy these limitations and improve the versatility of gene edits that can be created. Nonetheless, until issues with specificity and in vivo efficiency are resolved, utilization of CRISPR/Cas systems would be best employed in the modeling and study of various cancer genes. While it may have potential therapeutic applications to targeted cancer therapies in the future, presently CRISPR/Cas is a remarkable technique that can be utilized for easy and efficient gene editing when it comes to cancer research. J. Cell. Biochem. 119: 134-140, 2018. © 2017 Wiley Periodicals, Inc.

Dual Role of the Extracellular Domain of Human Mucin MUC1 in Metastasis

Human mucin MUC1 plays an important role in cancer development. The increased level of this molecule expression during cancer cell progression induces metastasis and is associated with poor prognosis for patients. There is a large body of experimental data on the role of various functional domains of human mucin MUC1 in metastasis. While, the cytoplasmic domain determined to play a definitive role, the influence of extracellular domain on cancer cell invasiveness still remains unclear. The present paper reveals that the extracellular domain of MUC1 molecule consists of two functional subdomains-the region of tandem repeats (TR) and the region of irregular repeats (IR). We demonstrate the ability of each of these subdomains to alter the invasiveness of cancer cells. The presence of the MUC1 molecules containing TR subdomain (MUC1-TR) on the surface of low-invasive cancer cells leads to the increase in their transendothelial migration potency, while the addition of the IR subdomain to the MUC1-TR molecule (MUC1-IR-TR) restores their natural low invasiveness. J. Cell. Biochem. 118: 4002-4011, 2017. © 2017 Wiley Periodicals, Inc.

RSPO3 expands intestinal stem cell and niche compartments and drives tumorigenesis

OBJECTIVE

The gross majority of colorectal cancer cases results from aberrant Wnt/β-catenin signalling through adenomatous polyposis coli (APC) or CTNNB1 mutations. However, a subset of human colon tumours harbour, mutually exclusive with APC and CTNNB1 mutations, gene fusions in RSPO2 or RSPO3, leading to enhanced expression of these R-spondin genes. This suggested that RSPO activation can substitute for the most common mutations as an alternative driver for intestinal cancer. Involvement of RSPO3 in tumour growth was recently shown in RSPO3-fusion-positive xenograft models. The current study determines the extent into which solely a gain in RSPO3 actually functions as a driver of intestinal cancer in a direct, causal fashion, and addresses the in vivo activities of RSPO3 in parallel.

DESIGN

We generated a conditional Rspo3 transgenic mouse model in which the Rspo3 transgene is expressed upon Cre activity. Cre is provided by cross-breeding with Lgr5-GFP-Cre^ERT2 mice.

RESULTS

Upon in vivo Rspo3 expression, mice rapidly developed extensive hyperplastic, adenomatous and adenocarcinomatous lesions throughout the intestine. RSPO3 induced the expansion of Lgr5⁺ stem cells, Paneth cells, non-Paneth cell label-retaining cells and Lgr4⁺ cells, thus promoting both intestinal stem cell and niche compartments. Wnt/β-catenin signalling was modestly increased upon Rspo3 expression and mutant Kras synergised with Rspo3 in hyperplastic growth.

CONCLUSIONS

We provide in vivo evidence that RSPO3 stimulates the crypt stem cell and niche compartments and drives rapid intestinal tumorigenesis. This establishes RSPO3 as a potent driver of intestinal cancer and proposes RSPO3 as a candidate target for therapy in patients with colorectal cancer harbouring RSPO3 fusions.

The HDAC6 Inhibitor Tubacin Induces Release of CD133+ Extracellular Vesicles From Cancer Cells

Tumor-derived extracellular vesicles (EVs) are emerging as an important mode of intercellular communication, capable of transferring biologically active molecules that facilitate the malignant growth and metastatic process. CD133 (Prominin-1), a stem cell marker implicated in tumor initiation, differentiation and resistance to anti-cancer therapy, is reportedly associated with EVs in various types of cancer. However, little is known about the factors that regulate the release of these CD133⁺ EVs. Here, we report that the HDAC6 inhibitor tubacin promoted the extracellular release of CD133⁺ EVs from human FEMX-I metastatic melanoma and Caco-2 colorectal carcinoma cells, with a concomitant downregulation of intracellular CD133. This effect was specific for tubacin, as inhibition of HDAC6 deacetylase activity by another selective HDAC6 inhibitor, ACY-1215 or the pan-HDAC inhibitor trichostatin A (TSA), and knockdown of HDAC6 did not enhance the release of CD133⁺ EVs. The tubacin-induced EV release was associated with changes in cellular lipid composition, loss of clonogenic capacity and decrease in the ability to form multicellular aggregates. These findings indicate a novel potential anti-tumor mechanism for tubacin in CD133-expressing malignancies. J. Cell. Biochem. 118: 4414-4424, 2017. © 2017 Wiley Periodicals, Inc.

Immune Checkpoint Blockade Biology in Mouse Models of Glioblastoma

Glioblastoma Multiforme (GBM) is a highly malignant primary brain cancer that is associated with abysmal prognosis. The median survival of GBM patients is ∼15 months and there have not been any significant advance in therapies in over a decade, leaving treatment options limited. There is clearly an unmet need for GBM treatment. Immunotherapies are treatments based on usurping the power of the host's immune system to recognize and eliminate cancer cells. They have recently proven to be a successful strategy for combating a variety of cancers. Of the various types of immunotherapies, checkpoint blockade approaches have thus far produced significant clinical responses in several cancers including melanoma, non small-cell lung cancer, renal cancer, and prostate cancer. This review focuses on the biological rationale for using checkpoint blockade immunotherapeutic approaches in primary brain cancer and an up-to-date summary of current and ongoing checkpoint inhibitors-based clinical trials for malignant glioma. In addition, we expand on new concepts for further improving checkpoint blockade treatments, with a particular focus on the advantages of using genetically engineered mouse models for studies of immunotherapies in GBM. J. Cell. Biochem. 118: 2516-2527, 2017. © 2017 Wiley Periodicals, Inc.

BVES regulates c-Myc stability via PP2A and suppresses colitis-induced tumourigenesis

OBJECTIVE

Blood vessel epicardial substance (BVES) is a tight junction-associated protein that regulates epithelial-mesenchymal states and is underexpressed in epithelial malignancy. However, the functional impact of BVES loss on tumourigenesis is unknown. Here we define the in vivo role of BVES in colitis-associated cancer (CAC), its cellular function and its relevance to patients with IBD.

DESIGN

We determined BVES promoter methylation status using an Infinium HumanMethylation450 array screen of patients with UC with and without CAC. We also measured BVES mRNA levels in a tissue microarray consisting of normal colons and CAC samples. Bves^-/- and wild-type mice (controls) were administered azoxymethane (AOM) and dextran sodium sulfate (DSS) to induce tumour formation. Last, we used a yeast two-hybrid screen to identify BVES interactors and performed mechanistic studies in multiple cell lines to define how BVES reduces c-Myc levels.

RESULTS

BVES mRNA was reduced in tumours from patients with CAC via promoter hypermethylation. Importantly, BVES promoter hypermethylation was concurrently present in distant non-malignant-appearing mucosa. As seen in human patients, Bves was underexpressed in experimental inflammatory carcinogenesis, and Bves^-/- mice had increased tumour multiplicity and degree of dysplasia after AOM/DSS administration. Molecular analysis of Bves^-/- tumours revealed Wnt activation and increased c-Myc levels. Mechanistically, we identified a new signalling pathway whereby BVES interacts with PR61α, a protein phosphatase 2A regulatory subunit, to mediate c-Myc destruction.

CONCLUSION

Loss of BVES promotes inflammatory tumourigenesis through dysregulation of Wnt signalling and the oncogene c-Myc. BVES promoter methylation status may serve as a CAC biomarker.

Gleason grade grouping of prostate cancer is of prognostic value in Asian men

AIM

The International Society of Urological Pathology made recommendations for the use of Grade Groups (GG) originally described by Epstein and colleagues over Gleason score (GS) alone in 2014, which was subsequently adopted by the WHO classification in 2016. The majority of studies validating this revision have been in Caucasian populations. We therefore asked whether the new GG system was retrospectively associated with biochemical disease-free survival in a mixed-ethnicity cohort of Asian men.

METHODS

A total of 680 radical prostatectomies (RPs) from 2005 to 2014 were included. GS from initial biopsy and RP were compared and used to allocate cases to GG, defined as: 1 (GS≤6); 2 (GS 3+4=7); 3 (GS 4+3=7); 4 (GS 4+4=8/5+3=8/3+5=8) and 5 (GS 9-10). Biochemical recurrence was defined as two consecutive post-RP prostate-specific antigen (PSA) levels of >0.2 ng/mL after post-RP PSA reaching the nadir of <0.1 ng/mL.

RESULTS

Our data showed that Kaplan-Meier analysis revealed significant differences in biochemical recurrence within Gleason GG based on either biopsy or prostatectomy scoring. Multivariate analysis further confirmed that a higher GG was significantly associated with risk of biochemical recurrence. This GG system had a higher prognostic discrimination for both initial biopsy and RP than GS.

CONCLUSIONS

Our study validates the use of the revised and updated GG system in a mixed-ethnicity population of Asian men. Higher GG was significantly associated with increased risk of biochemical recurrence. We therefore recommend its use to inform clinical management for patients with prostate cancer.

Expression of PTEN and its pseudogene PTENP1, and promoter methylation of PTEN in non-tumourous thymus and thymic tumours

AIMS

Mutation or promoter methylation of the phosphatase tensin homologue deleted on chromosome 10 tumour suppressor gene (PTEN) promotes some cancers. Moreover, PTENP1 (PTEN pseudogene) transcript regulates PTEN expression and is thought to be associated with tumourigenesis in some cancers. Here, we investigated PTEN expression in thymic epithelium and thymic epithelial tumours.

METHODS

Immunohistochemical analysis of PTEN was performed on two non-tumourous thymus (NT) samples, 33 thymomas (three type A, eight type AB, 11 type B1, six type B2, and five type B3), and four thymic carcinomas (TCs). In 16 cases (two NT, three A, five B1, two B2, one B3 and three TC), analyses of mutations, promoter methylation and comparisons of PTEN mRNA and PTENP1 transcripts were undertaken using PCR-direct sequencing, methylation-specific PCR, and reverse-transcription real-time PCR after target cell collection with laser microdissection.

RESULTS

PTEN protein was not immunohistochemically detected in NT epithelium or types B1 or B2 thymoma cells, but was expressed in type A thymoma and carcinoma cells. Neither PTEN mutations nor promoter methylation were detected in any samples. Statistical analysis revealed that PTEN mRNA expression was highest in NT epithelium and lowest in type A thymoma cells. PTENP1 transcript expression did not significantly differ among NT, thymoma and TC samples.

CONCLUSIONS

We speculated that NT epithelium and types B1/B2 thymoma cells have a mechanism of PTEN translation repression and/or acceleration of protein degradation, whereas type A thymoma cells exhibit transcriptional repression of PTEN mRNA and accelerated translation and/or protein accumulation.

Phosphofructokinase-P Modulates P44/42 MAPK Levels in HeLa Cells

It is known that interfering with glycolysis leads to profound modification of cancer cell proliferation. However, energy production is not the major reason for this correlation. Here, using HeLa cells as a model for cancer, we demonstrate that phosphofructokinase-P (PFK-P), which is overexpressed in diverse types of cancer including HeLa cells, modulates expression of P44/42 mitogen-activated protein kinase (MAPK). Silencing of PFK-P did not alter HeLa cell viability or energy production, including the glycolytic rate. On the other hand, silencing of PFK-P induced the downregulation of p44/42 MAPK, augmenting the sensitivity of HeLa cells to different drugs. Conversely, overexpression of PFK-P promotes the upregulation of p44/42 MAPK, making the cells more resistant to the drugs. These results indicate that overexpression of PFK-P by cancer cells is related to activation of survival pathways via upregulation of MAPK and suggest PFK-P as a promising target for cancer therapy. J. Cell. Biochem. 118: 1216-1226, 2017. © 2016 Wiley Periodicals, Inc.

Methyl-CpG-Binding Protein (MBD) Family: Epigenomic Read-Outs Functions and Roles in Tumorigenesis and Psychiatric Diseases

Epigenetics is the study of the heritable changes on gene expression that are responsible for the regulation of development and that have an impact on several diseases. However, it is of equal importance to understand how epigenetic machinery works. DNA methylation is the most studied epigenetic mark and is generally associated with the regulation of gene expression through the repression of promoter activity and by affecting genome stability. Therefore, the ability of the cell to interpret correct methylation marks and/or the correct interpretation of methylation plays a role in many diseases. The major family of proteins that bind methylated DNA is the methyl-CpG binding domain proteins, or the MBDs. Here, we discuss the structure that makes these proteins a family, the main functions and interactions of all protein family members and their role in human disease such as psychiatric disorders and cancer.