Estimates of the worldwide incidence and mortality from 27 major cancers and for all cancers combined for 2012 are now available in the GLOBOCAN series of the International Agency for Research on Cancer. We review the sources and methods used in compiling the national cancer incidence and mortality estimates, and briefly describe the key results by cancer site and in 20 large “areas” of the world. Overall, there were 14.1 million new cases and 8.2 million deaths in 2012. The most commonly diagnosed cancers were lung (1.82 million), breast (1.67 million), and colorectal (1.36 million); the most common causes of cancer death were lung cancer (1.6 million deaths), liver cancer (745,000 deaths), and stomach cancer (723,000 deaths). What's new? In this report, we present the most recent cancer incidence and mortality statistics (for 2012) for the major cancers in 20 regions of the world. Details of the data sources and methods used in GLOBOCAN to compile the estimates at the national level are provided, and we introduce a novel alphanumeric scoring system to give a broad indication of the robustness of the estimation within each country. A global snapshot of the patterns by cancer site brings focus to the need for regional prioritisation of cancer control efforts, as well as the ongoing efforts to improve the limited surveillance systems in many low and middle income countries.
Recent estimates of global cancer incidence and survival were used to update previous figures of limited duration prevalence to the year 2008. The number of patients with cancer diagnosed between 2004 and 2008 who were still alive at the end of 2008 in the adult population is described by world region, country and the human development index. The 5‐year global cancer prevalence is estimated to be 28.8 million in 2008. Close to half of the prevalence burden is in areas of very high human development that comprise only one‐sixth of the world's population. Breast cancer continues to be the most prevalent cancer in the vast majority of countries globally; cervix cancer is the most prevalent cancer in much of Sub‐Saharan Africa and Southern Asia and prostate cancer dominates in North America, Oceania and Northern and Western Europe. Stomach cancer is the most prevalent cancer in Eastern Asia (including China); oral cancer ranks as the most prevalent cancer in Indian men and Kaposi sarcoma has the highest 5‐year prevalence among men in 11 countries in Sub‐Saharan Africa. The methods used to estimate point prevalence appears to give reasonable results at the global level. The figures highlight the need for long‐term care targeted at managing patients with certain very frequently diagnosed cancer forms. To be of greater relevance to cancer planning, the estimation of other time‐based measures of global prevalence is warranted.
Estimates of the worldwide incidence and mortality from 27 cancers in 2008 have been prepared for 182 countries as part of the GLOBOCAN series published by the International Agency for Research on Cancer. In this article, we present the results for 20 world regions, summarizing the global patterns for the eight most common cancers. Overall, an estimated 12.7 million new cancer cases and 7.6 million cancer deaths occur in 2008, with 56% of new cancer cases and 63% of the cancer deaths occurring in the less developed regions of the world. The most commonly diagnosed cancers worldwide are lung (1.61 million, 12.7% of the total), breast (1.38 million, 10.9%) and colorectal cancers (1.23 million, 9.7%). The most common causes of cancer death are lung cancer (1.38 million, 18.2% of the total), stomach cancer (738,000 deaths, 9.7%) and liver cancer (696,000 deaths, 9.2%). Cancer is neither rare anywhere in the world, nor mainly confined to high-resource countries. Striking differences in the patterns of cancer from region to region are observed.
Limited population‐based cancer registry data available in China until now has hampered efforts to inform cancer control policy. Following extensive efforts to improve the systematic cancer surveillance in this country, we report on the largest pooled analysis of cancer survival data in China to date. Of 21 population‐based cancer registries, data from 17 registries ( n = 138,852 cancer records) were included in the final analysis. Cases were diagnosed in 2003–2005 and followed until the end of 2010. Age‐standardized relative survival was calculated using region‐specific life tables for all cancers combined and 26 individual cancers. Estimates were further stratified by sex and geographical area. The age‐standardized 5‐year relative survival for all cancers was 30.9% (95% confidence intervals : 30.6%‐31.2%). Female breast cancer had high survival (73.0%) followed by cancers of the colorectum (47.2%), stomach (27.4%), esophagus (20.9%), with lung and liver cancer having poor survival (16.1% and 10.1%), respectively. Survival for women was generally higher than for men. Survival for rural patients was about half that of their urban counterparts for all cancers combined (21.8% vs . 39.5%); the pattern was similar for individual major cancers except esophageal cancer. The poor population survival rates in China emphasize the urgent need for government policy changes and investment to improve health services. While the causes for the striking urban‐rural disparities observed are not fully understood, increasing access of health service in rural areas and providing basic health‐care to the disadvantaged populations will be essential for reducing this disparity in the future. What's new? Because it's difficult to create good public‐health policies without good population data, China has recently made efforts to improve its systematic recording of cancer data. This paper reports the largest pooled analysis of survival data in China, the first to include data from a wide range of geographical areas. They report the various survival rates for different cancers by age, gender, and locality. The most striking finding was that those living in rural residents had far lower survival rates than urban residents. This finding may prompt efforts to improve availability of cancer prevention and treatment in rural areas of China.
HPV is the cause of almost all cervical cancer and is responsible for a substantial fraction of other anogenital cancers and oropharyngeal cancers. Understanding the HPV‐attributable cancer burden can boost programs of HPV vaccination and HPV‐based cervical screening. Attributable fractions (AFs) and the relative contributions of different HPV types were derived from published studies reporting on the prevalence of transforming HPV infection in cancer tissue. Maps of age‐standardized incidence rates of HPV‐attributable cancers by country from GLOBOCAN 2012 data are shown separately for the cervix, other anogenital tract and head and neck cancers. The relative contribution of HPV16/18 and HPV6/11/16/18/31/33/45/52/58 was also estimated. 4.5% of all cancers worldwide (630,000 new cancer cases per year) are attributable to HPV: 8.6% in women and 0.8% in men. AF in women ranges from 20% in India and sub‐Saharan Africa. Cervix accounts for 83% of HPV‐attributable cancer, two‐thirds of which occur in less developed countries. Other HPV‐attributable anogenital cancer includes 8,500 vulva; 12,000 vagina; 35,000 anus (half occurring in men) and 13,000 penis. In the head and neck, HPV‐attributable cancers represent 38,000 cases of which 21,000 are oropharyngeal cancers occurring in more developed countries. The relative contributions of HPV16/18 and HPV6/11/16/18/31/33/45/52/58 are 73% and 90%, respectively. Universal access to vaccination is the key to avoiding most cases of HPV‐attributable cancer. The preponderant burden of HPV16/18 and the possibility of cross‐protection emphasize the importance of the introduction of more affordable vaccines in less developed countries. What's new? Most cervical cancers result from human papillomavirus (HPV) infection and therefore are preventable through screening and vaccination. Nonetheless, efforts toward HPV‐attributable cancer prevention frequently are undermined by limited access to necessary resources. The present study estimates that worldwide as many as 4.5% of new cancer cases, including cancers of the cervix, anogenital tract and head and neck, are associated with HPV infection. Cervical cancer alone accounts for 83% of those cases, most of which affect women in less‐developed countries. The findings emphasize the importance of HPV screening and vaccination and the need for less‐costly vaccines.
In most areas of the world, thyroid cancer incidence has been appreciably increasing over the last few decades, whereas mortality has steadily declined. We updated global trends in thyroid cancer mortality and incidence using official mortality data from the World Health Organization (1970–2012) and incidence data from the Cancer Incidence in Five Continents (1960–2007). Male mortality declined in all the major countries considered, with annual percent changes around −2/−3% over the last decades. Only in the United States mortality declined up to the mid 1980s and increased thereafter. Similarly, in women mortality declined in most countries considered, with APCs around −2/−5% over the last decades, with the exception of the UK, the United States and Australia, where mortality has been declining up to the late 1980s/late 1990s to level off (or increase) thereafter. In 2008–2012, most countries had mortality rates (age‐standardized, world population) between 0.20 and 0.40/100,000 men and 0.20 and 0.60/100,000 women, the highest rates being in Latvia, Hungary, the Republic of Moldova and Israel (over 0.40/100,000) for men and in Ecuador, Colombia and Israel (over 0.60/100,000) for women. In most countries, a steady increase in the incidence of thyroid cancer (mainly papillary carcinomas) was observed in both sexes. The declines in thyroid cancer mortality reflect both variations in risk factor exposure and changes in the diagnosis and treatment of the disease, while the increases in the incidence are likely due to the increase in the detection of this neoplasm over the last few decades. What's New? Trends in thyroid cancer incidence and mortality vary widely by country, but for most areas of the world, the data indicate an upward trend in incidence and a downward trend in mortality. Those trends are supported by the present analysis of thyroid cancer mortality and incidence globally. The analyses are based on data maintained by the World Health Organization (1970–2012) and Cancer Incidence in Five Continents (1960–2007). The authors attribute the rise in thyroid cancer incidence to increased detection of the disease and the decline in mortality to changes in diagnosis, treatment, and risk factor exposure.
Genotyping may improve risk stratification of high‐risk (HR) human papillomavirus (HPV)‐positive women in cervical screening programs; however, prospective data comparing the natural history and carcinogenic potential of individual HR types remain limited. A meta‐analysis of cross‐sectional HR HPV‐type distribution in 115,789 HPV‐positive women was performed, including 33,154 normal cytology, 6,810 atypical squamous cells of undetermined significance (ASCUS), 13,480 low‐grade squamous intraepithelial lesions (LSIL) and 6,616 high‐grade SIL (HSIL) diagnosed cytologically, 8,106 cervical intraepithelial neoplasia grade 1 (CIN1), 4,068 CIN2 and 10,753 CIN3 diagnosed histologically and 36,374 invasive cervical cancers (ICCs) from 423 PCR‐based studies worldwide. No strong differences in HPV‐type distribution were apparent between normal cytology, ASCUS, LSIL or CIN1. However, HPV16 positivity increased steeply from normal/ASCUS/LSIL/CIN1 (20–28%), through CIN2/HSIL (40/47%) to CIN3/ICC (58/63%). HPV16, 18 and 45 accounted for a greater or equal proportion of HPV infections in ICC compared to normal cytology (ICC:normal ratios = 3.07, 1.87 and 1.10, respectively) and to CIN3 (ICC:CIN3 ratios = 1.08, 2.11 and 1.47, respectively). Other HR types accounted for important proportions of HPV‐positive CIN2 and CIN3, but their contribution dropped in ICC, with ICC:normal ratios ranging from 0.94 for HPV33 down to 0.16 for HPV51. ICC:normal ratios were particularly high for HPV45 in Africa (1.85) and South/Central America (1.79) and for HPV58 in Eastern Asia (1.36). ASCUS and LSIL appear proxies of HPV infection rather than cancer precursors, and even CIN3 is not entirely representative of the types causing ICC. HPV16 in particular, but also HPV18 and 45, warrant special attention in HPV‐based screening programs.
Angiogenesis, a critical driver of tumor development, is controlled by interconnected signaling pathways. Vascular endothelial growth factor receptor (VEGFR) 2 and tyrosine kinase with immunoglobulin and epidermal growth factor homology domain 2 play crucial roles in the biology of normal and tumor vasculature. Regorafenib (BAY 73‐4506), a novel oral multikinase inhibitor, potently inhibits these endothelial cell kinases in biochemical and cellular kinase phosphorylation assays. Furthermore, regorafenib inhibits additional angiogenic kinases (VEGFR1/3, platelet‐derived growth factor receptor‐β and fibroblast growth factor receptor 1) and the mutant oncogenic kinases KIT, RET and B‐RAF. The antiangiogenic effect of regorafenib was demonstrated in vivo by dynamic contrast‐enhanced magnetic resonance imaging. Regorafenib administered once orally at 10 mg/kg significantly decreased the extravasation of Gadomer in the vasculature of rat GS9L glioblastoma tumor xenografts. In a daily (qd)×4 dosing study, the pharmacodynamic effects persisted for 48 hr after the last dosing and correlated with tumor growth inhibition (TGI). A significant reduction in tumor microvessel area was observed in a human colorectal xenograft after qd×5 dosing at 10 and 30 mg/kg. Regorafenib exhibited potent dose‐dependent TGI in various preclinical human xenograft models in mice, with tumor shrinkages observed in breast MDA‐MB‐231 and renal 786‐O carcinoma models. Pharmacodynamic analyses of the breast model revealed strong reduction in staining of proliferation marker Ki‐67 and phosphorylated extracellular regulated kinases 1/2. These data demonstrate that regorafenib is a well‐tolerated, orally active multikinase inhibitor with a distinct target profile that may have therapeutic benefit in human malignancies.
Pooled data on human papillomavirus (HPV) type distribution in invasive cervical cancer (ICC) can help to predict the potential impact of HPV type‐specific vaccines and screening tests, and to understand the carcinogenicity of HPV types. We performed a meta‐analysis of HPV type‐specific prevalence data published from 1990 to 2010, including a total of 243 studies and 30,848 ICC. The proportion of ICC associated with HPV16 and/or 18 (HPV16/18) was between 70 and 76% in all world regions except Asia. In Western/Central Asia, 82% of ICC was HPV16/18‐associated compared to only 68% in Eastern Asia. The 12 most common HPV types identified, in order of decreasing prevalence, were HPV16 (57%), 18 (16%), 58, 33, 45, 31, 52, 35, 59, 39, 51 and 56. The prevalence of other types, phylogenetically related to those above, ranged from <0.1% for HPV85 to 0.6% for HPV68. Overall HPV prevalence increased significantly from 85.9% in studies published from 1990 to 1999 to 92.9% in studies published from 2006 to 2010. Prevalence increases were large for multiple infections (from 4.0 to 15.7%) and for HPV16 (from 51.8 to 60.0%, including HPV16 alone or in multiple infections). Smaller but significant increases in prevalence were also seen for HPV39, 53 and 58. A large amount of recently published data has improved the understanding of the contribution of a broad range of HPV types to ICC in different world regions. However, estimating the fraction of ICC attributable to different types is increasingly complicated by the detection of multiple HPV infections in ICC.
Knowledge about human papillomaviruses (HPV) types involved in anal cancers in some world regions is scanty. Here, we describe the HPV DNA prevalence and type distribution in a series of invasive anal cancers and anal intraepithelial neoplasias (AIN) grades 2/3 from 24 countries. We analyzed 43 AIN 2/3 cases and 496 anal cancers diagnosed from 1986 to 2011. After histopathological evaluation of formalin‐fixed paraffin‐embedded samples, HPV DNA detection and genotyping was performed using SPF‐10/DEIA/LiPA 25 system (version 1) . A subset of 116 cancers was further tested for p16 INK4a expression, a cellular surrogate marker for HPV‐associated transformation. Prevalence ratios were estimated using multivariate Poisson regression with robust variance in the anal cancer data set. HPV DNA was detected in 88.3% of anal cancers (95% confidence interval [CI]: 85.1–91.0%) and in 95.3% of AIN 2/3 (95% CI: 84.2–99.4%). Among cancers, the highest prevalence was observed in warty–basaloid subtype of squamous cell carcinomas, in younger patients and in North American geographical region. There were no statistically significant differences in prevalence by gender. HPV16 was the most frequent HPV type detected in both cancers (80.7%) and AIN 2/3 lesions (75.4%). HPV18 was the second most common type in invasive cancers (3.6%). p16 INK4a overexpression was found in 95% of HPV DNA‐positive anal cancers. In view of the results of HPV DNA and high proportion of p16 INK4a overexpression, infection by HPV is most likely to be a necessary cause for anal cancers in both men and women. The large contribution of HPV16 reinforces the potential impact of HPV vaccines in the prevention of these lesions. What's new? Human papillomavirus (HPV) is linked to anal cancer through high HPV DNA‐detection rates. Here, in one of the largest international studies to date, HPV DNA was detected in more than 88% of anal cancers and more than 95% of anal intraepithelial neoplasias grades 2/3. HPV16 was the most frequently detected virus type, followed by HPV18. Overexpression of p16 INK4a , a surrogate marker for HPV‐associated transformation, was found in 95% of HPV‐positive anal cancers. The data implicate HPV as a causative factor in anal cancer.
The incidence of cutaneous malignant melanoma has steadily increased over the past 50 years in predominately fair‐skinned populations. This increase is reported to have leveled off recently in several Northern and Western European countries, Australia, New Zealand and in North America. We studied the global patterns and time trends in incidence of melanoma by country and sex, with a focus on and age‐ and cohort‐specific variations. We analyzed the incidence data from 39 population‐based cancer registries, examining all‐ages and age‐truncated standardized incidence rates of melanoma, estimating the annual percentage change and incidence rate ratios from age‐period‐cohort models. Incidence rates of melanoma continue to rise in most European countries (primarily Southern and Eastern Europe), whereas in Australia, New Zealand, the U.S., Canada, Israel and Norway, rates have become rather stable in recent years. Indications of a stabilization or decreasing trend were observed mainly in the youngest age group (25–44 years). Rates have been rising steadily in generations born up to the end of the 1940s, followed by a stabilization or decline in rates for more recently born cohorts in Australia, New Zealand, the U.S., Canada and Norway. In addition to the birth cohort effect, there was a suggestion of a period‐related influence on melanoma trends in certain populations. Although our findings provide support that primary and secondary prevention can halt and reverse the observed increasing burden of melanoma, they also indicate that those prevention measures require further endorsement in many countries.
MicroRNA (miRNA) opens up a new field for molecular diagnosis of cancer. However, the role of circulating miRNAs in plasma/serum in cancer diagnosis is not clear. The aim of this study was to investigate whether plasma miRNAs can be used as biomarkers for the early detection of colorectal carcinoma (CRC). We measured the levels of 12 miRNAs (miR‐134, −146a, −17‐3p, −181d, −191, −221, −222, −223, −25, −29a, −320a and −92a) in plasma samples from patients with advanced colorectal neoplasia (carcinomas and advanced adenomas) and healthy controls using real‐time RT‐PCR. We found that plasma miR‐29a and miR‐92a have significant diagnostic value for advanced neoplasia. MiR‐29a yielded an AUC (the areas under the ROC curve) of 0.844 and miR‐92a yielded an AUC of 0.838 in discriminating CRC from controls. More importantly, these 2 miRNAs also could discriminate advanced adenomas from controls and yielded an AUC of 0.769 for miR‐29a and 0.749 for miR‐92a. Combined ROC analyses using these 2 miRNAs revealed an elevated AUC of 0.883 with 83.0% sensitivity and 84.7% specificity in discriminating CRC, and AUC of 0.773 with 73.0% sensitivity and 79.7% specificity in discriminating advanced adenomas. Collectively, these data suggest that plasma miR‐29a and miR‐92a have strong potential as novel noninvasive biomarkers for early detection of CRC.
The incidence of cutaneous malignant melanoma has steadily increased over the past 50 years in predominately fair-skinned populations. This increase is reported to have leveled off recently in several Northern and Western European countries, Australia, New Zealand and in North America. We studied the global patterns and time trends in incidence of melanoma by country and sex, with a focus on and age- and cohort-specific variations. We analyzed the incidence data from 39 population-based cancer registries, examining all-ages and age-truncated standardized incidence rates of melanoma, estimating the annual percentage change and incidence rate ratios from age-period-cohort models. Incidence rates of melanoma continue to rise in most European countries (primarily Southern and Eastern Europe), whereas in Australia, New Zealand, the U.S., Canada, Israel and Norway, rates have become rather stable in recent years. Indications of a stabilization or decreasing trend were observed mainly in the youngest age group (2544 years). Rates have been rising steadily in generations born up to the end of the 1940s, followed by a stabilization or decline in rates for more recently born cohorts in Australia, New Zealand, the U.S., Canada and Norway. In addition to the birth cohort effect, there was a suggestion of a period-related influence on melanoma trends in certain populations. Although our findings provide support that primary and secondary prevention can halt and reverse the observed increasing burden of melanoma, they also indicate that those prevention measures require further endorsement in many countries.
We previously estimated that 660,000 cases of cancer in the year 2008 were attributable to the bacterium Helicobacter pylori (H. pylori), corresponding to 5.2% of the 12.7 million total cancer cases that occurred worldwide. In recent years, evidence has accumulated that immunoblot (western blot) is more sensitive for detection of anti-H. pylori antibodies than ELISA, the detection method used in our previous analysis. The purpose of this short report is to update the attributable fraction (AF) estimate for H. pylori after briefly reviewing new evidence, and to reassess the global burden of cancer attributable to H. pylori. We therefore reviewed the literature for studies comparing the risk of developing non-cardia gastric cancer (NCGC) in cases and controls, using both ELISA and multiple antigen immunoblot for detection of H. pylori. The results from prospective studies were combined, and the new pooled estimates were applied to the calculation of the AF for H. pylori in NCGC, then to the burden of infection-related cancers worldwide. Using the immunoblot-based data, the worldwide AF for H. pylori in NCGC increased from 74.7% to 89.0%. This implies approximately 120,000 additional cases of NCGC attributable to H. pylori infection for a total of around 780,000 cases (6.2% instead of 5.2% of all cancers). These updated estimates reinforce the role of H. pylori as a major cause of cancer. What's new? Some 5.2 percent of the estimated 12.7 million new cancer cases in 2008, including 75% of non-cardia gastric cancer cases (NCGC), were attributed to the bacterium Helicobacter pylori. However, those percentages may be an underestimate, given the low sensitivity of detection of anti-H. pylori antibodies. Here, using improved estimates from prospective studies based on immunoblot, the fraction of all cancers and NCGC attributable to H. pylori was found to be 6.2 and 89% percent, respectively. Our findings reinforce the significance of the bacterium as a major cause of cancer.
Melanoma remains among the most lethal cancers and, in spite of great attempts that have been made to increase the life span of patients with metastatic disease, durable and complete remissions are rare. Plants and plant extracts have long been used to treat a variety of human conditions; however, in many cases, effective doses of herbal remedies are associated with serious adverse effects. Curcumin is a natural polyphenol that shows a variety of pharmacological activities including anti‐cancer effects, and only minimal adverse effects have been reported for this phytochemical. The anti‐cancer effects of curcumin are the result of its anti‐angiogenic, pro‐apoptotic and immunomodulatory properties. At the molecular and cellular level, curcumin can blunt epithelial‐to‐mesenchymal transition and affect many targets that are involved in melanoma initiation and progression ( e.g., BCl2, MAPKS, p21 and some microRNAs). However, curcumin has a low oral bioavailability that may limit its maximal benefits. The emergence of tailored formulations of curcumin and new delivery systems such as nanoparticles, liposomes, micelles and phospholipid complexes has led to the enhancement of curcumin bioavailability. Although in vitro and in vivo studies have demonstrated that curcumin and its analogues can be used as novel therapeutic agents in melanoma, curcumin has not yet been tested against melanoma in clinical practice. In this review, we summarized reported anti‐melanoma effects of curcumin as well as studies on new curcumin formulations and delivery systems that show increased bioavailability. Such tailored delivery systems could pave the way for enhancement of the anti‐melanoma effects of curcumin.
The prognostic role of inflammation index like neutrophil‐to‐lymphocyte ratio (NLR) in colorectal cancer (CRC) remains controversial. We conduct a meta‐analysis to determine the predictable value of NLR in the clinical outcome of CRC patients. The analysis was carried out based on the data from 16 studies (19 cohorts) to evaluate the association between NLR and overall survival (OS) and progression‐free survival (PFS) in patients with CRC. In addition, the relationship between NLR and clinicopathological parameters was assessed. Hazard ratio (HR) or odds ratio (OR) with its 95% confidence interval (CI) was used as the effect size estimate. Our analysis results indicated that elevated pretreatment NLR predicted poorer OS (HR: 1.813, 95% CI: 1.499–2.193) and PFS (HR: 2.102, 95% CI: 1.554–2.843) in patients with CRC. Increased NLR is also significantly associated with the poorer differentiation of the tumor (OR: 1.574, 95% CI: 1.226–2.022) and higher carcino‐embryonie antigen (CEA) level (OR: 1.493, 95% CI: 1.308–1.705). By these results, we conclude that NLR gains a prognostic value for patients with CRC. NLR should be monitored in CRC patients for rational stratification of the patients and adjusting the treatment strategy. What's new? Although correlated with the severity of disease course, the impact of neutrophil‐to‐lymphocyte ratio (NLR) on survival and tumor characteristics in cancer patients remains unclear. In the meta‐analysis presented here, elevated pre‐treatment NLR was found to predict poor overall survival in patients with colorectal cancer. NLR was also associated with unfavorable biologic behavior in colorectal cancer. The findings suggest that NLR, as an inexpensive and widely available index, should be routinely monitored in colorectal cancer patients.
Recent studies have revealed that Foxp3(+)CD25(+)CD4(+) regulatory T cells (Tregs), which are physiologically engaged in the maintenance of immunological self-tolerance, play critical roles for the control of antitumor immune responses. For example, a large number of Foxp3(+)Tregs infiltrate into tumors, and systemic removal of Foxp3(+)Tregs enhances natural as well as vaccine-induced antitumor T-cell responses. Tregs are recruited to tumor tissues via chemokines, such as CCL22 binding to CCR4 expressed by Tregs. They appear to expand and become activated in tumor tissues and in the draining lymph nodes by recognizing tumor-associated antigens as well as normal self-antigen expressed by tumor cells. These results indicate that cancer vaccines targeting tumor-associated self-antigens may potentially expand/activate Tregs and hamper effective antitumor immune responses, and that tumor immunity can therefore be enhanced by depleting Tregs, attenuating Treg suppressive function, or rendering effector T cells refractory to Treg-mediated suppression. Recent attempts have indeed demonstrated that combinations of monoclonal antibodies capable of modulating Treg functions synergistically enhance antitumor activity and are more effective than a single monoclonal antibody therapy. Combination therapy targeting a variety of molecules expressed in antigen-presenting cells, effector T cells and Tregs is envisaged to be a promising anticancer immunotherapy.
Late diagnosis contributes to pancreatic cancer (PaCa) dismal prognosis, urging for reliable, early detection. Serum‐exosome protein and/or miRNA markers might be suitable candidates, which we controlled for patients with PaCa. Protein markers were selected according to expression in exosomes of PaCa cell line culture supernatants, but not healthy donors' serum‐exosomes. miRNA was selected according to abundant recovery in microarrays of patients with PaCa, but not healthy donors' serum‐exosomes and exosome‐depleted serum. According to these preselections, serum‐exosomes were tested by flow cytometry for the PaCa‐initiating cell (PaCIC) markers CD44v6, Tspan8, EpCAM, MET and CD104. Serum‐exosomes and exosome‐depleted serum was tested for miR‐1246, miR‐4644, miR‐3976 and miR‐4306 recovery by qRT‐PCR. The majority (95%) of patients with PaCa (131) and patients with nonPa‐malignancies reacted with a panel of anti‐CD44v6, ‐Tspan8, ‐EpCAM and ‐CD104. Serum‐exosomes of healthy donors' and patients with nonmalignant diseases were not reactive. Recovery was tumor grading and staging independent including early stages. The selected miR‐1246, miR‐4644, miR‐3976 and miR‐4306 were significantly upregulated in 83% of PaCa serum‐exosomes, but rarely in control groups. These miRNA were also elevated in exosome‐depleted serum of patients with PaCa, but at a low level. Concomitant evaluation of PaCIC and miRNA serum‐exosome marker panels significantly improved sensitivity (1.00, CI: 0.95–1) with a specificity of 0.80 (CI: 0.67–0.90) for PaCa versus all others groups and of 0.93 (CI: 0.81–0.98) excluding nonPa‐malignancies. Thus, the concomitant evaluation of PaCIC and PaCa‐related miRNA marker panels awaits retrospective analyses of larger cohorts, as it should allow for a highly sensitive, minimally‐invasive PaCa diagnostics. What's new? Tumor exosomes—membrane vesicles of endocytic origin abundantly secreted by tumor cells and readily detected in body fluids—have recently emerged as a potential, non‐invasive diagnostic tool. This study shows that the serum of pancreatic cancer (PaCa) patients contains detectable amounts of PaCa stem cell marker‐expressing exosomes. Furthermore, the miRNA profile of serum exosomes in PaCa patients differs significantly from that of healthy donors and patients with non‐malignant disease. A blinded screening study of PaCa patients' serum exosomes revealed a combined evaluation of a panel of PaCa‐associated miRNA and stem cell biomarkers to provide a highly sensitive, minimally‐invasive diagnostic tool.
Non‐thermal plasma (NTP) is generated by ionizing neutral gas molecules/atoms leading to a highly reactive gas at ambient temperature containing excited molecules, reactive species and generating transient electric fields. Given its potential to interact with tissue or cells without a significant temperature increase, NTP appears as a promising approach for the treatment of various diseases including cancer. The aim of our study was to evaluate the interest of NTP both in vitro and in vivo. To this end, we evaluated the antitumor activity of NTP in vitro on two human cancer cell lines (glioblastoma U87MG and colorectal carcinoma HCT‐116). Our data showed that NTP generated a large amount of reactive oxygen species (ROS), leading to the formation of DNA damages. This resulted in a multiphase cell cycle arrest and a subsequent apoptosis induction. In addition, in vivo experiments on U87MG bearing mice showed that NTP induced a reduction of bioluminescence and tumor volume as compared to nontreated mice. An induction of apoptosis was also observed together with an accumulation of cells in S phase of the cell cycle suggesting an arrest of tumor proliferation. In conclusion, we demonstrated here that the potential of NTP to generate ROS renders this strategy particularly promising in the context of tumor treatment.
Signal transducer and activator of transcription 3 (STAT3) is constitutively activated in numerous cancer types, including more than 40% of breast cancers. In contrast to tight regulation of STAT3 as a latent transcription factor in normal cells, its signaling in breast cancer oncogenesis is multifaceted. Signaling through the IL‐6/JAK/STAT3 pathway initiated by the binding of IL‐6 family of cytokines ( i.e ., IL‐6 and IL‐11) to their receptors have been implicated in breast cancer development. Receptors with intrinsic kinase activity such as EGFR and VEGFR directly or indirectly induce STAT3 activation in various breast cancer types. Aberrant STAT3 signaling promotes breast tumor progression through deregulation of the expression of downstream target genes which control proliferation (Bcl‐2, Bcl‐xL, Survivin, Cyclin D1, c‐Myc and Mcl‐1), angiogenesis (Hif1α and VEGF) and epithelial–mesenchymal transition (Vimentin, TWIST, MMP‐9 and MMP‐7). These multiple modes of STAT3 regulation therefore make it a central linking point for a multitude of signaling processes. Extensive efforts to target STAT3 activation in breast cancer had no remarkable success in the past because the highly interconnected nature of STAT3 signaling introduces lack of selectivity in pathway identification for STAT3 targeted molecular therapies or because its role in tumorigenesis may not be as critical as it was thought. This review provides a full spectrum of STAT3's involvement in breast cancer by consolidating the knowledge about its role in breast cancer development at multiple levels: its differential regulation by different receptor signaling pathways, its downstream target genes, and modification of its transcriptional activity by its coregulatory transcription factors.