scholarly journals POTENTIAL MECHANISMS OF CANCER PREVENTION BY WEIGHT CONTROL

2008 ◽  
Vol 03 (03) ◽  
pp. 421-437 ◽  
Author(s):  
YU JIANG ◽  
WEIQUN WANG

Weight control via dietary caloric restriction and/or physical activity has been demonstrated in animal models for cancer prevention. However, the underlying mechanisms are not fully understood. Body weight loss due to negative energy balance significantly reduces some metabolic growth factors and endocrinal hormones such as IGF-1, leptin, and adiponectin, but enhances glucocorticoids, that may be associated with anti-cancer mechanisms. In this review, we summarized the recent studies related to weight control and growth factors. The potential molecular targets focused on those growth factors- and hormones-dependent cellular signaling pathways are further discussed. It appears that multiple factors and multiple signaling cascades, especially for Ras-MAPK-proliferation and PI3K-Akt-anti-apoptosis, could be involved in response to weight change by dietary calorie restriction and/or exercise training. Considering prevalence of obesity or overweight that becomes apparent over the world, understanding the underlying mechanisms among weight control, endocrine change and cancer risk is critically important. Future studies using "-omics" technologies will be warrant for a broader and deeper mechanistic information regarding cancer prevention by weight control.

2018 ◽  
Vol 18 (2) ◽  
pp. 156-165 ◽  
Author(s):  
Jiaqiang Wang ◽  
Chien-shan Cheng ◽  
Yan Lu ◽  
Xiaowei Ding ◽  
Minmin Zhu ◽  
...  

Background: Propofol, a widely used intravenous anesthetic agent, is traditionally applied for sedation and general anesthesia. Explanation: Recent attention has been drawn to explore the effect and mechanisms of propofol against cancer progression in vitro and in vivo. Specifically, the proliferation-inhibiting and apoptosis-inducing properties of propofol in cancer have been studied. However, the underlying mechanisms remain unclear. Conclusion: This review focused on the findings within the past ten years and aimed to provide a general overview of propofol's malignance-modulating properties and the potential molecular mechanisms.


Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3688
Author(s):  
Jéssica Fernanda Barazetti ◽  
Tayana Shultz Jucoski ◽  
Tamyres Mingorance Carvalho ◽  
Rafaela Nasser Veiga ◽  
Ana Flávia Kohler ◽  
...  

Breast cancer is the most commonly diagnosed cancer and the leading cause of cancer mortality among women. Two thirds of patients are classified as hormone receptor positive, based on expression of estrogen receptor alpha (ERα), the main driver of breast cancer cell proliferation, and/or progesterone receptor, which is regulated by ERα. Despite presenting the best prognosis, these tumors can recur when patients acquire resistance to treatment by aromatase inhibitors or antiestrogen such as tamoxifen (Tam). The mechanisms that are involved in Tam resistance are complex and involve multiple signaling pathways. Recently, roles for microRNAs and lncRNAs in controlling ER expression and/or tamoxifen action have been described, but the underlying mechanisms are still little explored. In this review, we will discuss the current state of knowledge on the roles of microRNAs and lncRNAs in the main mechanisms of tamoxifen resistance in hormone receptor positive breast cancer. In the future, this knowledge can be used to identify patients at a greater risk of relapse due to the expression patterns of ncRNAs that impact response to Tam, in order to guide their treatment more efficiently and possibly to design therapeutic strategies to bypass mechanisms of resistance.


Antioxidants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 634
Author(s):  
Anca Ungurianu ◽  
Anca Zanfirescu ◽  
Georgiana Nițulescu ◽  
Denisa Margină

Vitamin E, comprising tocopherols and tocotrienols, is mainly known as an antioxidant. The aim of this review is to summarize the molecular mechanisms and signaling pathways linked to inflammation and malignancy modulated by its vitamers. Preclinical reports highlighted a myriad of cellular effects like modulating the synthesis of pro-inflammatory molecules and oxidative stress response, inhibiting the NF-κB pathway, regulating cell cycle, and apoptosis. Furthermore, animal-based models have shown that these molecules affect the activity of various enzymes and signaling pathways, such as MAPK, PI3K/Akt/mTOR, JAK/STAT, and NF-κB, acting as the underlying mechanisms of their reported anti-inflammatory, neuroprotective, and anti-cancer effects. In clinical settings, not all of these were proven, with reports varying considerably. Nonetheless, vitamin E was shown to improve redox and inflammatory status in healthy, diabetic, and metabolic syndrome subjects. The anti-cancer effects were inconsistent, with both pro- and anti-malignant being reported. Regarding its neuroprotective properties, several studies have shown protective effects suggesting vitamin E as a potential prevention and therapeutic (as adjuvant) tool. However, source and dosage greatly influence the observed effects, with bioavailability seemingly a key factor in obtaining the preferred outcome. We conclude that this group of molecules presents exciting potential for the prevention and treatment of diseases with an inflammatory, redox, or malignant component.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Chen Li ◽  
Yan Wang ◽  
Yueqing Gong ◽  
Tengrui Zhang ◽  
Jiaqi Huang ◽  
...  

AbstractEnhancer of zeste homolog 2 inhibitors (EZH2i) have garnered increased attention owing to their anticancer activity by targeting EZH2, a well-known cancer-promoting factor. However, some lymphomas are resistant to EZH2i, and EZH2i treatment alone is ineffective in case of EZH2-overexpressing solid tumors. The anti-cancer efficacy of EZH2i may be improved through safe and effective combinations of these drugs with other treatment modalities. Preclinical evidence indicates that combining EZH2i with other therapies, such as immunotherapy, chemotherapy, targeted therapy, and endocrine therapy, has complementary or synergistic antitumor effects. Therefore, elucidating the underlying mechanisms of the individual constituents of the combination therapies is fundamental for their clinical application. In this review, we have summarized notable clinical trials and preclinical studies using EZH2i, their progress, and combinations of EZH2i with different therapeutic modalities, aiming to provide new insights for tumor treatment.


2020 ◽  
Vol 21 (23) ◽  
pp. 9018
Author(s):  
Ranjini Sankaranarayanan ◽  
D. Ramesh Kumar ◽  
Meric A. Altinoz ◽  
G. Jayarama Bhat

Aspirin, synthesized and marketed in 1897 by Bayer, is one of the most widely used drugs in the world. It has a well-recognized role in decreasing inflammation, pain and fever, and in the prevention of thrombotic cardiovascular diseases. Its anti-inflammatory and cardio-protective actions have been well studied and occur through inhibition of cyclooxygenases (COX). Interestingly, a vast amount of epidemiological, preclinical and clinical studies have revealed aspirin as a promising chemopreventive agent, particularly against colorectal cancers (CRC); however, the primary mechanism by which it decreases the occurrences of CRC has still not been established. Numerous mechanisms have been proposed for aspirin’s chemopreventive properties among which the inhibition of COX enzymes has been widely discussed. Despite the wide attention COX-inhibition has received as the most probable mechanism of cancer prevention by aspirin, it is clear that aspirin targets many other proteins and pathways, suggesting that these extra-COX targets may also be equally important in preventing CRC. In this review, we discuss the COX-dependent and -independent pathways described in literature for aspirin’s anti-cancer effects and highlight the strengths and limitations of the proposed mechanisms. Additionally, we emphasize the potential role of the metabolites of aspirin and salicylic acid (generated in the gut through microbial biotransformation) in contributing to aspirin’s chemopreventive actions. We suggest that the preferential chemopreventive effect of aspirin against CRC may be related to direct exposure of aspirin/salicylic acid or its metabolites to the colorectal tissues. Future investigations should shed light on the role of aspirin, its metabolites and the role of the gut microbiota in cancer prevention against CRC.


2019 ◽  
Vol 14 (1) ◽  
pp. 5-18 ◽  
Author(s):  
Fabrizio Fontana ◽  
Michela Raimondi ◽  
Monica Marzagalli ◽  
Roberta M. Moretti ◽  
Marina Montagnani Marelli ◽  
...  

Background: Tocotrienols (TTs) are vitamin E derivatives naturally occurring in several plants and vegetable oils. Like Tocopherols (TPs), they comprise four isoforms, α, β, γ and δ, but unlike TPs, they present an unsaturated isoprenoid chain. Recent studies indicate that TTs provide important health benefits, including neuroprotective, anti-inflammatory, anti-oxidant, cholesterol lowering and immunomodulatory effects. Moreover, they have been found to possess unique anti-cancer properties.Objective:The purpose of this review is to present an overview of the state of the art of TTs role in cancer prevention and treatment, as well as to describe recent patents proposing new methods for TTs isolation, chemical modification and use in cancer prevention and/or therapy.Methods:Recent literature and patents focusing on TTs anti-cancer applications have been identified and reviewed, with special regard to their scientific impact and novelty.Results:TTs have demonstrated significant anti-cancer activity in multiple tumor types, both in vitro and in vivo. Furthermore, they have shown synergistic effects when given in combination with standard anti-cancer agents or other anti-tumor natural compounds. Finally, new purification processes and transgenic sources have been designed in order to improve TTs production, and novel TTs formulations and synthetic derivatives have been developed to enhance their solubility and bioavailability.Conclusion:The promising anti-cancer effects shown by TTs in several preclinical studies may open new opportunities for therapeutic interventions in different tumors. Thus, clinical trials aimed at confirming TTs chemopreventive and tumor-suppressing activity, particularly in combination with standard therapies, are urgently needed.


2011 ◽  
pp. 31-42
Author(s):  
Jessica A. Miller ◽  
Patricia A. Thompson ◽  
Iman A. Hakim ◽  
H.-H. Sherry Chow ◽  
Cynthia A. Thomson

Although limited, observations from cell culture, animal, and epidemiological studies support the presence of anti-cancer properties in citrus peel and the primary bioactive food constituent, d-limonene. Early evidence from animal models suggests that when ingested, d-limonene exhibits a wide spectrum of biologic activity including chemotherapeutic and chemopreventive effects. In some of these early models, an analog of d-limonene, perillyl alcohol, demonstrated a more potent effect than d-limonene itself. Yet, when perillyl alcohol advanced to clinical trials, several trials were ended early due to doselimiting toxicities. Alternatively, oral d-limonene administration in humans is well tolerated even at high doses supporting its investigation as a potential bioactive for cancer prevention. Though the exact mechanisms of action of d-limonene are unclear, immune modulation and antiproliferative effects are commonly reported. Here, we review the pre-clinical evidence for d-limonene’s anticancer mechanisms, bioavailability, and safety, as well as the evidence for anti-cancer effects in humans, focusing on studies relevant to its use in the prevention and treatment of breast cancer.


2018 ◽  
Vol 68 (2) ◽  
pp. 193 ◽  
Author(s):  
V. KANOULAS ◽  
G. A. PAPADOPOULOS ◽  
G. ARSENOS ◽  
E. D. TZIKA ◽  
P. FORTOMARIS

The present study investigated the effects of attapulgite supplementation in sow diets during gestation and lactation on sow performance. The study comprised two reproductive phases (cycles) in two commercial farrow to finish farms: Farm A (capacity: 550 sows) and Farm B (capacity: 220 sows). The treatment groups were: a) control group (CN): the sows were fed a common gestation or lactation diet; b) attapulgite group (AT): the sows were fed the CN diet supplemented with attapulgite at 0,7% level; c) attapulgite plus group (AT+): the sows were fed the CN diet supplemented with attapulgite (0.7%) and a mix of enzymes, live yeast and amino acids (0.1%), at a total of 0.8% level. Within each cycle the sows included per treatment were: 24 for Farm A; 12 for Farm B. Initially data were analyzed per cycle and per each farm. Data from sows that completed both cycles within each farm, were analyzed by repeated measures analysis. Regarding sow parameters, sow body weight loss during lactation tended to be greater in AT sows compared to CN sows during cycle 1 in Farm B and was greater in AT and AT+ than CN sows in Farm A that completed both cycles (P=0.063 and P=0.023, respectively). A greater litter size 24h postpartum was observed in favour of AT compared to CN group during cycle 1 in Farm A and in sows that completed both cycles in Farm A (P=0.001 and P= 0.011, respectively). Litter size at weaning was greater in sows from the AT group than CN during cycle 1 and 2 in Farm A, in cycle 1 in Farm B and in sows that completed both cycles in Farm A (P=0.004, P=0.037, P=0.037, and P=0.022, respectively). Piglet weight at weaning and average daily gain during lactation were greater in AT group than CN and AT+ in sows that completed both cycles in Farm A (P=0.049 and P=0.040 respectively). Notable similar effects, although not statistically significant, were also observed in Farm B. This field study suggests that attapulgite supplementation in sow diets can improve performance indexes. Further research should investigate the underlying mechanisms involved.


2021 ◽  
pp. 096032712110544
Author(s):  
Zi-tan Peng ◽  
Pei Gu

Objective Sulforaphane, which exerts an effective anti-cancer ability, is a phytochemical converted from cruciferous plants. Here, we aimed to identify whether sulforaphane could suppress autophagy during the malignant progression of gastric carcinoma and to explore the underlying mechanisms. Methods SGC7901 cells were transfected with miR-4521 mimics, inhibitor, and pcDNA3.1- PIK3R3, and treated with sulforaphane or autophagy inhibitor. Cell proliferation, apoptosis, and miR-4521 or PIK3R3 expression were detected. Results MiR-4521 over-expression suppressed LC3-II/I ratio and Beclin-1 expression but induced p62 expression in SGC7901 cells. MiR-4521 also reduced gastric carcinoma cell proliferation and promoted apoptosis in vitro. In the mechanical observation, we identified that miR-4521 directly targeted PIK3R3 to repress its expression, and PIK3R3 up-regulation partly antagonized miR-4521-mediated autophagy, proliferation, and apoptosis in gastric carcinoma cells. In addition, sulforaphane exerted effective anti-cancer functions by repressing autophagy and growth in tumor cells at a concentration-dependent way. MiR-4521 inhibition or PIK3R3 over-expression weakened the anti-cancer functions of sulforaphane in gastric carcinoma cells. Conclusion Consequently, miR-4521 suppressed autophagy during the malignant progression of gastric carcinoma by targeting PIK3R3. Thus, miR-4521 may be applied as a therapeutic target for sulforaphane in gastric carcinoma.


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