Potential of Orlistat to induce apoptotic and antiangiogenic effects as well as inhibition of fatty acid synthesis in breast cancer cells

Unveiling the potential of isatin-grafted phenyl-1,2,3-triazole derivatives as dual VEGFR-2/STAT-3 inhibitors: Design, synthesis and biological assessments

The use of VEGFR-2 inhibitors as a stand-alone treatment has proven to be ineffective in clinical trials due to the robustness of cellular response loops that lead to treatment resistance when only targeting VEGFR-2. The over-activation of the signal transducer/activator of transcription 3 (STAT-3) is expected to significantly impact treatment failure and resistance to VEGFR-2 inhibitors. In this study, we propose the concept of combined inhibition of VEGFR-2 and STAT-3 to combat induced STAT-3-mediated resistance to VEGFR-2 inhibition therapy. To explore this, we synthesized new isatin-grafted phenyl-1,2,3-triazole derivatives "6a-n" and "9a-f". Screening on PANC1 and PC3 cancer cell lines revealed that compounds 6b, 6 k, 9c, and 9f exhibited sub-micromolar ranges. The most promising molecules, 6b, 6 k, 9c, and 9f, demonstrated the highest inhibition when tested as dual inhibitors on VEGFR-2 (with IC50 range 53-82 nM, respectively) and STAT-3 (with IC50 range 5.63-10.25 nM). In particular, triazole 9f showed the best results towards both targets. Inspired by these findings, we investigated whether 9f has the ability to trigger apoptosis in prostate cancer PC3 cells via the assessment of the expression levels of the apoptotic markers Caspase-8, Bcl-2, Bax, and Caspase-9. Treatment of the PC3 cells with compound 9f significantly inhibited the protein expression levels of VEGFR-2 and STAT-3 kinases compared to the control.

Weight-centric prevention of cancer

Background

The link between excess adiposity and carcinogenesis has been well established for multiple malignancies, and cancer is one of the main contributors to obesity-related mortality. The potential role of different weight-loss interventions on cancer risk modification has been assessed, however, its clinical implications remain to be determined. In this clinical review, we present the data assessing the effect of weight loss interventions on cancer risk.

Methods

In this clinical review, we conducted a comprehensive search of relevant literature using MEDLINE, Embase, Web of Science, and Google Scholar databases for relevant studies from inception to January 20, 2024. In this clinical review, we present systematic reviews and meta-analysis, randomized clinical trials, and prospective and retrospective observational studies that address the effect of different treatment modalities for obesity in cancer risk. In addition, we incorporate the opinions from experts in the field of obesity medicine and oncology regarding the potential of weight loss as a preventative intervention for cancer.

Results

Intentional weight loss achieved through different modalities has been associated with a reduced cancer incidence. To date, the effect of weight loss on the postmenopausal women population has been more widely studied, with multiple reports indicating a protective effect of weight loss on hormone-dependent malignancies. The effect of bariatric interventions as a protective intervention for cancer has been studied extensively, showing a significant reduction in cancer incidence and mortality, however, data for the effect of bariatric surgery on certain specific types of cancer is conflicting or limited.

Conclusion

Medical nutrition therapy, exercise, antiobesity medication, and bariatric interventions, might lead to a reduction in cancer risk through weight loss-dependent and independent factors. Further evidence is needed to better determine which population might benefit the most, and the amount of weight loss required to provide a clinically significant preventative effect.

Structure-guided optimization of 3-hydroxybenzoisoxazole derivatives as inhibitors of Aldo-keto reductase 1C3 (AKR1C3) to target prostate cancer

AKR1C3 is an enzyme that is overexpressed in several types of radiotherapy- and chemotherapy-resistant cancers. Despite AKR1C3 is a validated target for drug development, no inhibitor has been approved for clinical use. In this manuscript, we describe our study of a new series of potent AKR1C3-targeting 3-hydroxybenzoisoxazole based inhibitors that display high selectivity over the AKR1C2 isoform and low micromolar activity in inhibiting 22Rv1 prostate cancer cell proliferation. In silico studies suggested proper substituents to increase compound potency and provided with a mechanistic explanation that could clarify their different activity, later confirmed by X-ray crystallography. Both the in-silico studies and the crystallographic data highlight the importance of 90° rotation around the single bond of the biphenyl group, in ensuring that the inhibitor can adopt the optimal binding mode within the active pocket. The p-biphenyls that bear the meta-methoxy, and the ortho- and meta-trifluoromethyl substituents (in compounds 6a, 6e and 6f respectively) proved to be the best contributors to cellular potency as they provided the best IC50 values in series (2.3, 2.0 and 2.4 μM respectively) and showed no toxicity towards human MRC-5 cells. Co-treatment with scalar dilutions of either compound 6 or 6e and the clinically used drug abiraterone led to a significant reduction in cell proliferation, and thus confirmed that treatment with both CYP171A1-and AKR1C3-targeting compounds possess the potential to intervene in key steps in the steroidogenic pathway. Taken together, the novel compounds display desirable biochemical potency and cellular target inhibition as well as good in-vitro ADME properties, which highlight their potential for further preclinical studies.

Development of new thieno[2,3-d]pyrimidines as dual EGFR and STAT3 inhibitors endowed with anticancer and pro-apoptotic activities

In part due to the resilience of cellular feedback pathways that develop therapeutic resistance to targeting the EGFR alone, using EGFR inhibitors alone was demonstrated to be unsuccessful in clinical trials. The over-activation of the signal transducer/activator of transcription 3 (STAT3) during the administration of an EGFR inhibitor is expected to play a substantial part in the failure and resistance of EGFR inhibitor treatment. Therein, we proposed a hypothesis that induced STAT3-mediated resistance to EGFR inhibition therapy could be addressed by a dual inhibition of EGFR and STAT3 method. To this end, we tried to discover new thieno[2,3-d]pyrimidine derivatives "5a-o". Results from the screening on A549 and MCF7 cancer cell lines revealed that compounds 5j and 5k showed two-digit nanomolar with appropriate safety towards the WI-38 cell line. The best molecules, 5j and 5k, were subjected to γ-radiation, and their cytotoxic efficacy didn't change after irradiation, demonstrating that not having to use it avoided its side effects. Compounds 5j and 5k demonstrated the highest inhibition when their potency was tested as dual inhibitors on EGFR 67 and 41 nM, respectively, and STAT3 5.52 and 3.34 nM, respectively, proved with in silico molecular docking and dynamic simulation. In light of the results presented above, the capacity of both powerful compounds to alter the cell cycle and initiate the apoptotic process in breast cancer MCF7 cells was investigated. Caspase-8, Bcl-2, Bax and Caspase-9 apoptotic indicators were studied.

Fabrication of Nanocrystals for Enhanced Distribution of a Fatty Acid Synthase Inhibitor (Orlistat) as a Promising Method to Relieve Solid Ehrlich Carcinoma-Induced Hepatic Damage in Mice

BACKGROUND

Orlistat (ORL) is an effective irreversible inhibitor of the lipase enzyme, and it possesses anticancer effects and limited aqueous solubility. This study was designed to improve the aqueous solubility, oral absorption, and tissue distribution of ORL via the formulation of nanocrystals (NCs).

METHODS

ORL-NC was prepared using the liquid antisolvent precipitation method (bottom-up technology), and it demonstrated significantly improved solubility compared with that of the blank crystals (ORL-BCs) and untreated ORL powder. The biodistribution and relative bioavailability of ORL-NC were investigated via the radiolabeling technique using Technetium-99m (99mTc). Female Swiss albino mice were used to examine the antitumor activity of ORL-NC against solid Ehrlich carcinoma (SEC)-induced hepatic damage in mice.

RESULTS

The prepared NCs improved ORL's solubility, bioavailability, and tissue distribution, with evidence of 258.70% relative bioavailability. In the in vivo study, the ORL-NC treatment caused a reduction in all tested liver functions (total and direct bilirubin, AST, ALT, and ALP) and improved modifications in liver sections that were marked using hematoxylin and eosin staining (H&E) and immunohistochemical staining (Ki-67 and ER-α) compared with untreated SEC mice.

CONCLUSIONS

The developed ORL-NC could be considered a promising formulation approach to enhance the oral absorption tissue distribution of ORL and suppress the liver damage caused by SEC.

Identification of 3-(5-cyano-6-oxo-pyridin-2-yl)benzenesulfonamides as novel anticancer agents endowed with EGFR inhibitory activity

New 5-cyano-6-oxo-pyridine-based sulfonamides (6a-m and 8a-d) were designed and synthesized to potentially inhibit both the epidermal growth factor receptor (EGFR) and carbonic anhydrase (CA), with anticancer properties. First, the in vitro anticancer activity of each target substance was tested using Henrietta Lacks cancer cell line and M.D. anderson metastasis breast cancer cell line cells. Then, the possible CA inhibition against the human CA isoforms I, II, and IX was investigated, together with the EGFR inhibitory activity, with the most powerful derivatives. The neighboring methoxy group may have had a steric effect on the target sulfonamides, which prevented them from effectively inhibiting the CA isoforms while effectively inhibiting the EGFR. The effects of the 5-cyanopyridine derivatives 6e and 6l on cell-cycle disruption and the apoptotic potential were then investigated. To investigate the binding mechanism and stability of the target molecules, thorough molecular modeling assessments, including docking and dynamic simulation, were performed.

FASN promotes gallbladder cancer progression and reduces cancer cell sensitivity to gemcitabine through PI3K/AKT signaling

Lipid metabolism plays an important role in the growth and development of tumors. However, the role of lipid metabolism in gallbladder cancer (GBC) has not been clearly clarified. Here, we demonstrated that fatty acid synthase (FASN), a key enzyme in de novo fatty acid biosynthesis, had upregulated expression in GBC samples both at protein and mRNA levels. Analysis of clinical data indicated the association between elevated FASN expression and poorer histology grades. Furthermore, FASN activity impairment through FASN knockdown or treatment with orlistat resulted in the inhibition of cell proliferation and migration, as well as increased sensitivity to gemcitabine. Both FASN knockdown and orlistat treatment induced cell apoptosis. Mechanistically, impairment of FASN activity suppressed the activation of the PI3K/AKT signaling pathway, which led to increased cell apoptosis and sensitivity to gemcitabine. These findings were also validated through nude mouse xenograft models, thus highlighting the potential of targeting FASN as a clinical treatment strategy. Collectively, the present study underscores the crucial role of FASN in the progression of gallbladder cancer via the PI3K/AKT pathway.

Comparison of orlistat and orlistat plus metformin therapy between diabetic and nondiabetic groups

OBJECTIVE

The objective of this study was to examine the effects of orlistat use on metabolic control and weight loss in diabetic and nondiabetic patients.

METHODS

A total of 119 patients with body mass index≥40 kg/m2 and receiving orlistat therapy, who applied to the Endocrinology polyclinic between January 2016 and October 2019, were included. The patients' weight changes and biochemical values (i.e., fasting glucose, HbA1c, ALT, creatinine, and lipid parameters) were evaluated at the drug beginning and the last polyclinic control. The patients were divided into groups, whether they had diabetes or used metformin, and compared.

RESULTS

The mean age of the 119 patients in the study was 45.3±11.5 years. A total of 94.1% of the patients were females and 5.9% were males. A total of 38.7% of the patients had diabetes and 29.4% had prediabetes. When the patients were compared to whether they had diabetes or used metformin, there was a statistically significant difference between the groups according to weight loss. The mean weight change of patients without diabetes and receiving metformin and orlistat was statistically significantly higher than that of patients with diabetes and receiving metformin and orlistat.

DISCUSSION

It was determined that the weight loss effect of orlistat in obesity was seen in all groups, but this effect decreased in the diabetic group.

The Metabolic Landscape of Breast Cancer and Its Therapeutic Implications

Breast cancer is the most common malignant tumor globally as of 2020 and remains the second leading cause of cancer-related death among female individuals worldwide. Metabolic reprogramming is well recognized as a hallmark of malignancy owing to the rewiring of multiple biological processes, notably, glycolysis, oxidative phosphorylation, pentose phosphate pathway, as well as lipid metabolism, which support the demands for the relentless growth of tumor cells and allows distant metastasis of cancer cells. Breast cancer cells are well documented to reprogram their metabolism via mutations or inactivation of intrinsic factors such as c-Myc, TP53, hypoxia-inducible factor, and the PI3K/AKT/mTOR pathway or crosstalk with the surrounding tumor microenvironments, including hypoxia, extracellular acidification and interaction with immune cells, cancer-associated fibroblasts, and adipocytes. Furthermore, altered metabolism contributes to acquired or inherent therapeutic resistance. Therefore, there is an urgent need to understand the metabolic plasticity underlying breast cancer progression as well as to dictate metabolic reprogramming that accounts for the resistance to standard of care. This review aims to illustrate the altered metabolism in breast cancer and its underlying mechanisms, as well as metabolic interventions in breast cancer treatment, with the intention to provide strategies for developing novel therapeutic treatments for breast cancer.

Obesity and multiple myeloma: emerging mechanisms and perspectives

Obesity is a global pandemic that has been associated with the development of breast, endometrial, large intestine, renal, esophageal, and pancreatic cancer. Obesity is also involved in the development of cardiovascular disease and type 2 diabetes mellitus. Recently, an increase in the incidence of obesity-related cancers has been reported. Multiple myeloma (MM) is the second most common hematological malignancy, after lymphoma. The aim of this review is to examine the epidemiological data on obesity and MM, assess the effect of obesity on MM outcomes, evaluate the possible mechanisms through which obesity might increase the incidence of MM and provide the effects of obesity management on MM. Current evidence indicates that obesity may have an impact on the progression of monoclonal gammopathy of undetermined significance (MGUS) to MM and increase the prevalence of MM. However, data regarding the effect of obesity on MGUS incidence are controversial; further studies are needed to examine whether obesity affects the development of MGUS or the progression of MGUS to MM. In addition, obesity affects MM outcomes. Increased BMI is associated with decreased survival in patients with MM, while data regarding the effect of obesity on newly diagnosed MM subjects and autologous stem cell transplantation are limited. Interestingly, the obesity paradox may also apply to patients with relapsed/refractory MM who are overweight or obese, because they may have a survival advantage. The pathophysiological pathways linking obesity to MM are very complicated and include bone marrow adipose tissue; adipokines, such as adiponectin, leptin, resistin, and visfatin; inflammatory cytokines and growth factors, such as TNF-α and IL-6; hormones including insulin and the insulin-like growth factor system as well as sex hormones. In terms of the effect of pharmacological management of obesity, orlistat has been shown to alter the proliferation of MM cells, whereas no data exist on glucagon-like peptide-1 receptor agonists, naltrexone/bupropion, or phentermine/topiramate. Bariatric surgery may be associated with a reduction in the incidence of MM, however, further studies are needed.