For colorectal cancer patients with type II diabetes, could metformin improve the survival rate? A meta-analysis

The association of benzodiazepine and benzodiazepine-related drugs with outcomes after surgery for colorectal cancer

Benzodiazepines increase plasma brain-derived neurotrophic factor (BDNF) level which, in turn, may improve survival in colorectal cancer (CRC) patients. This study aimed to evaluate the associations between benzodiazepine and benzodiazepine-related drugs (BZRD) use and outcomes of patients operated for CRC. This is a retrospective cohort study including patients operated for CRC at Limoges' University Hospital between 2010 and 2019. Data were collected from two sources: medical records of patients in the digestive, general and endocrine surgery department at Limoges University Hospital and from the Haute-Vienne general cancer registry. Patients were divided into benzodiazepine users and non-users. Outcomes were overall survival (OS) and recurrence-free survival (RFS). Among 504 patients who underwent surgery for CRC, 125 (24.8%) patients were treated with benzodiazepine/BZRD drugs. Users and non-users of benzodiazepine/BZRD showed no statistically significant differences in 5-year OS (45.5 ± 1.9% vs. 46.5 ± 1.1% p = 0.25) and 5-year RFS (41.0 ± 2.1% vs. 39.6 ± 1.3%, p = 0.94), even after adjustment for confounders and propensity score (OS: aHR=1.02, 95%CI: 0.71-1.48; RFS: aHR=1.00, 95%CI: 0.72-1.40). Subgroup analysis on CRC patients with psychiatric disorders revealed that benzodiazepine users had better RFS (aHR=0.58, 95%CI: 0.35-0.96) compared with non-users, particularly, patients with stages III or IV of CRC had better OS (aHR=0.27; 95%CI: 0.12-0.59) and RFS (aHR=0.30, 95%CI: 0.15-0.62). OS and RFS was significantly better in patients taking benzodiazepines classified as anxiolytics, having longer half-life, and producing active metabolites. In conclusion, benzodiazepine use was not associated with outcomes in CRC patients. Nevertheless, in subgroup of patients with psychiatric disorders and advanced CRC stage, benzodiazepine could improve survival.

Cytotoxicity and reversal effect of sertraline, fluoxetine, and citalopram on MRP1- and MRP7-mediated MDR

Cancer is one of the leading causes of death worldwide, and the development of resistance to chemotherapy drugs is a major challenge in treating malignancies. In recent years, researchers have focused on understanding the mechanisms of multidrug resistance (MDR) in cancer cells and have identified the overexpression of ATP-binding cassette (ABC) transporters, including ABCC1/MRP1 and ABCC10/MRP7, as a key factor in the development of MDR. In this study, we aimed to investigate whether three drugs (sertraline, fluoxetine, and citalopram) from the selective serotonin reuptake inhibitor (SSRI) family, commonly used as antidepressants, could be repurposed as inhibitors of MRP1 and MRP7 transporters and reverse MDR in cancer cells. Using a combination of in silico predictions and in vitro validations, we analyzed the interaction of MRP1 and MRP7 with the drugs and evaluated their ability to hinder cell resistance. We used computational tools to identify and analyze the binding site of these three molecules and determine their binding energy. Subsequently, we conducted experimental assays to assess cell viability when treated with various standard chemotherapies, both with and without the presence of SSRI inhibitors. Our results show that all three SSRI drugs exhibited inhibitory/reversal effects in the presence of chemotherapies on both MRP1-overexpressed cells and MRP7-overexpressed cells, suggesting that these medications have the potential to be repurposed to target MDR in cancer cells. These findings may open the door to using FDA-approved medications in combination therapy protocols to treat highly resistant malignancies and improve the efficacy of chemotherapy treatment. Our research highlights the importance of investigating and repurposing existing drugs to overcome MDR in cancer treatment.

Metformin Treatment Reduces CRC Aggressiveness in a Glucose-Independent Manner: An In Vitro and Ex Vivo Study

(1) Background: Metformin, an anti-diabetic drug, seems to protect against aggressive acquisition in colorectal cancers (CRCs). However, its mechanisms are still really unknown, raising questions about the possibility of its positive impact on non-diabetic patients with CRC. (2) Methods: An in vitro study based on human colon cancer cell lines and an ex vivo study with different colon cancer stages with proteomic and transcriptomic analyses were initiated. (3) Results: Metformin seems to protect from colon cancer invasive acquisition, irrespective of glucose concentration. (4) Conclusions: Metformin could be used as an adjuvant treatment to surgery for both diabetic and non-diabetic patients in order to prevent the acquisition of aggressiveness and, ultimately, recurrences.

Prognostic Impact of Type 2 Diabetes in Metastatic Colorectal Cancer

Background Diabetes mellitus (DM) is a prognostic factor for some malignancies, but its clinical implications in metastatic colorectal cancer (mCRC) patients are less clear. Therefore, we conducted a retrospective study to evaluate the impact of pre-existing type 2 diabetes mellitus (T2DM) on the survival outcomes of patients with newly diagnosed mCRC. Methodology We retrospectively included patients with newly diagnosed mCRC between January 2017 and June 2021 and with pre-existing T2DM. Data on the characteristics of patients, clinicopathological features, and drug exposure were collected from the electronic medical records. The primary endpoint was overall survival (OS). Secondary endpoints were progression-free survival (PFS) and treatment-related adverse events (TRAEs). Results Among 187 mCRC patients, 54 (28.8%) had T2DM. The median follow-up was 25 months. We observed 150 OS events and 168 PFS events. Diabetes significantly and negatively impacted PFS and OS. The median for PFS (mPFS) was eight and 16 months for T2DM and no T2DM patients, respectively (p < 0.0001; log-rank test). The median overall survival (mOS) was 15 and 29 months for T2DM and no T2DM patients, respectively (p < 0.0001; log-rank test). Patients with diabetes were more often overweight or obese (59.3% vs. 24.8%; p < 0.01) and had a poorer performance status (53.7% vs. 21.1% with Eastern Cooperative Oncology Group Performance Status 1; p < 0.01). Additionally, T2DM patients had more high-risk pathological features, including G3 grading tumors (27.7% vs. 12.0%; p = 0.01), lymph node involvement (p < 0.01), BRAF-mutated (35.1% vs. 6.8%; p < 0.01), and right-sided CRC (63.0% vs. 30.1%; p < 0.01). We found no statistically significant differences in TRAEs. Nevertheless, a significantly higher rate of grade 2-4 peripheral neuropathy (22.2% vs. 5.3%; p < 0.01) was reported in T2DM patients. Conclusions T2DM is a negative prognostic factor for survival in mCRC. The paper provides empirical evidence in favor of the joint control of both pathologies. Further research is needed to establish the robustness of our results.

The Association of Metformin, Other Antidiabetic Medications and Statins on the Prognosis of Rectal Cancer in Patients with Type 2 Diabetes: A Retrospective Cohort Study

Metformin and statin use have been associated with an improved prognosis for colorectal cancer in persons with type 2 diabetes (T2D). Data regarding rectal cancer (RC) have been inconclusive; therefore, we investigated the issue with high-quality data and a robust study design. We identified 1271 eligible patients with T2D and incident RC between 1998 and 2011 from the Diabetes in Finland (FinDM) database. Cox models were fitted for cause-specific mortality rates to obtain adjusted estimates of the hazard ratios (HR) with 95% confidence intervals (CI) in relation to use of antidiabetic medication (ADM) and statins before the RC diagnosis and for post-diagnostic use in a time-dependent exposure manner. No sufficient evidence was found for either pre- or post-diagnostic metformin use and RC mortality (HR 0.96, 95% CI 0.67–1.38, and 0.70, 95% CI 0.45–1.10, respectively) when compared to other oral ADMs. Both pre- and post-diagnostic statin use appeared to be inversely associated with mortality from RC (HR 0.77 95% CI 0.63–0.94, and 0.57, 95% CI 0.42–0.78, respectively). Our study was inconclusive as to the association of metformin use with the prognosis of RC, but statin use was found to predict reduced mortality, both from RC and from other causes of death in persons with T2D.

The effect of metformin on the survival of colorectal cancer patients with type 2 diabetes mellitus

Evidence from previous studies suggests a protective effect of metformin in patients with colorectal cancer (CRC). The aim of this study was to examine the associations between metformin use and overall survival (OS) and disease-free survival (DFS) in CRC patients with type 2 diabetes mellitus (DM). We retrospectively included patients who underwent surgery for CRC at Limoges’ University Hospital between 2005 and 2019 and diagnosed with type 2 DM. Data on the characteristics of patients, CRC, comorbidities and drug exposure were collected from the electronic medical records. The exposure was the use of metformin and the outcomes were OS and DFS. We identified 290 CRC patients with type 2 DM. A total of 144 (49.7%) of them were treated with metformin. Metformin users were significantly younger, with higher body mass index and less diabetes-related complications compared to non-users. The 2-year OS was significantly higher in metformin users than in non-users (86.9 ± 2.9% vs. 71.0 ± 4.0%, p = 0.001). In multivariate analysis, metformin use was associated with better OS (adjusted hazard ratios [aHR] = 0.45 95% confidence interval [95% CI]: 0.21–0.96) and better DFS (aHR = 0.31; 95% CI: 0.18–0.54). In conclusion, the use of metformin may improve OS and DFS in CRC patients with type 2 DM.

Metformin inhibits the development and metastasis of colorectal cancer

Metformin is a commonly used drug for the treatment of diabetes. Accumulating evidence suggests that it exerts anti-cancer effects in many cancers, including colorectal cancer. However, the underlying molecular mechanisms of colorectal cancer metastasis remain unclear. Colorectal cancer cell lines were treated with metformin, and cell proliferation, invasion, and migration were analyzed in vitro. The relationship between metformin and the AMPK-mTOR axis was assessed by Western blot analysis and transfection with small interfering RNA. A colorectal cancer xenograft mouse model was used to observe the effects of metformin on liver metastasis. Immunohistochemical analysis was performed on liver metastatic tumors. In in vitro experiments, metformin significantly inhibited the proliferation, migration, and invasion only in HCT116 and SW837 cells, but not in HCT8 and Lovo cells. Only in HCT116 and SW837, a change in AMPK-mTOR expression was observed in a dose-dependent manner. In colorectal cancer xenograft mice, the liver metastatic rate (10% vs. 50%, p = 0.05) and the number of liver metastatic nodules (0.1/body vs. 1.2/body, p = 0.04) were significantly lower in the metformin group. Tumor proliferation and EMT were decreased and apoptosis was promoted only in metastatic liver tumors of mice treated with metformin. The molecular mechanism of the anti-cancer effects of metformin involves repression of mTOR pathways via AMPK activation. Moreover, the differences in metformin sensitivity depend on the response of the AMPK-mTOR pathway to metformin. Our study provides a theoretical basis for the anti-metastatic treatment of colorectal cancer using metformin.

In Vivo and In Vitro Enhanced Tumoricidal Effects of Metformin, Active Vitamin D3, and 5-Fluorouracil Triple Therapy against Colon Cancer by Modulating the PI3K/Akt/PTEN/mTOR Network

Simple Summary

Failure of chemotherapy is common during the treatment of colon cancer, and there is a compelling need to develop alternative therapeutic approaches against this common malignancy. Metformin, which is an oral hypoglycaemic agent used for treating diabetes mellitus, and vitamin D have shown promising anticancer activities, and both agents boosted the actions of chemotherapy against colon cancer. This study, therefore, measured the potential beneficial effects of adding metformin and/or active vitamin D to the main cytotoxic drug used for treating colon cancer. The results demonstrate that metformin had superior anticancer effects relative to active vitamin D and ameliorated the effects of chemotherapy in animals and in cells. To the best of our knowledge, this study is also the first to report that triple treatment with the drugs of interest showed the best inhibition of cancer progression, which could provide a better therapeutic strategy against colon cancer.

Abstract

Chemoresistance to 5-fluorouracil (5-FU) is common during colorectal cancer (CRC) treatment. This study measured the chemotherapeutic effects of 5-FU, active vitamin D₃ (VD₃), and/or metformin single/dual/triple regimens as complementary/alternative therapies. Ninety male mice were divided into: negative and positive (PC) controls, and 5-FU, VD₃, Met, 5-FU/VD₃, 5-FU/Met, VD₃/Met, and 5-FU/VD₃/Met groups. Treatments lasted four weeks following CRC induction by azoxymethane. Similar regimens were also applied in the SW480 and SW620 CRC cell lines. The PC mice had abundant tumours, markedly elevated proliferation markers (survivin/CCND1) and PI3K/Akt/mTOR, and reduced p21/PTEN/cytochrome C/caspase-3 and apoptosis. All therapies reduced tumour numbers, with 5-FU/VD₃/Met being the most efficacious regimen. All protocols decreased cell proliferation markers, inhibited PI3K/Akt/mTOR molecules, and increased proapoptotic molecules with an apoptosis index, and 5-FU/VD₃/Met revealed the strongest effects. In vitro, all therapies equally induced G1 phase arrest in SW480 cells, whereas metformin-alone showed maximal SW620 cell numbers in the G0/G1 phase. 5-FU/Met co-therapy also showed the highest apoptotic SW480 cell numbers (13%), whilst 5-FU/VD₃/Met disclosed the lowest viable SW620 cell percentages (81%). Moreover, 5-FU/VD₃/Met revealed maximal inhibitions of cell cycle inducers (CCND1/CCND3), cell survival (BCL2), and the PI3K/Akt/mTOR molecules alongside the highest expression of cell cycle inhibitors (p21/p27), proapoptotic markers (BAX/cytochrome C/caspase-3), and PTEN in both cell lines. In conclusion, metformin monotherapy was superior to VD₃, whereas the 5-FU/Met protocol showed better anticancer effects relative to the other dual therapies. However, the 5-FU/VD₃/Met approach displayed the best in vivo and in vitro tumoricidal effects related to cell cycle arrest and apoptosis, justifiably by enhanced modulations of the PI3K/PTEN/Akt/mTOR pathway.

The Association of Metformin, Other Antidiabetic Medications, and Statins With the Prognosis of Colon Cancer in Patients With Type 2 Diabetes: A Retrospective Cohort Study

BACKGROUND

Use of metformin and statins have been associated with improved prognosis of colon cancer (CC) in patients with type 2 diabetes (T2D). We examined the survival from CC in relation to the use of metformin, other oral antidiabetic medications (ADM), insulin, and statins in T2D patients.

MATERIALS AND METHODS

A cohort (n = 2252) of persons with pre-existing T2D diagnosed with incident CC between 1998 and 2011 was identified from several Finnish registers. Cox models were fitted for cause-specific mortality rates to obtain adjusted estimates of the hazard ratios (HR) with 95% confidence intervals (CI) in relation to use of ADM and statins before the CC diagnosis. Cox models were also fitted for mortality in relation to post-diagnostic use of the medications treating these as time-dependent exposures, and starting follow-up 1 year after the CC diagnosis.

RESULTS

Pre- and post-diagnostic metformin use was weakly associated with the risk of CC-related death (HR .75; 95% CI .58-.99, and HR .78; 95% CI .54-1.14, respectively) compared to the use of other oral ADMs. Pre- and post-diagnostic statin use predicted a reduced risk of CC-related death (HR .83; 95% CI .71- .98, and HR .69; 95% CI .54-.89, respectively).

CONCLUSION

Additional evidence was found for use of statins being associated with an improved survival from CC in patients with pre-existing T2D, but for metformin use the evidence was weaker.

Effect of metformin use on the risk and prognosis of colorectal cancer in diabetes mellitus: a meta-analysis

BACKGROUND

Whether metformin is a protective factor of colorectal cancer (CRC) among CRC patients is still not entirely clear. Thus, we conducted this systemic review and meta-analysis to provide a comprehensive review of associations between metformin therapy and CRC risk or survival outcomes for clinical decisions.

METHODS

Articles published before July 2021 were searched in databases (PubMed and Web of Science). Odds ratio (OR)/risk ratio (RR) or hazard ratio (HR) and their confidence intervals (CIs) were computed using STATA 12.0 software. Q test and I2 were conducted to explore heterogeneities between studies.

RESULTS

The present meta-analysis showed that metformin use was associated with decreased risk and lower all-cause mortality of CRC in diabetes mellitus (DM) with random-effects models (risk: OR/RR = 0.71, 95% CI, 0.64-0.80, I2 = 89.3%, P < 0.001; all-cause mortality: HR = 0.72, 95% CI, 0.62-0.83, I2 = 60.1%, P = 0.014). In addition, the study showed that metformin use was associated with a lower CRC-specific mortality in DM in cohort studies with a fixed-effects model (HR = 0.80, 95% CI, 0.70-0.92, I2 = 34.7%, P = 0.190).

CONCLUSION

Overall, in this meta-analysis, we found that metformin may be a protective factor for CRC risk and prognosis in patients with DM. Further well-designed, large-scale clinical studies are needed to evaluate the accuracy of our findings and more preclinical experiments are needed to reveal the underlying mechanism of metformin.

Lipopolysaccharide promotes metastasis via acceleration of glycolysis by the nuclear factor-κB/snail/hexokinase3 signaling axis in colorectal cancer

BACKGROUND

Cancer cell is generally characterized by enhanced glycolysis. Inflammasome activation is interaction with glycolysis. The concentration of lipopolysaccharide (LPS), a classic inflammasome activator, is significantly higher in colorectal cancer tissue than in normal intestinal mucosa. However, the mechanism of LPS on glycolysis and metastasis has not been fully elucidated. This study aimed to investigate the roles of LPS on inflammasome activation, glycolysis, and metastasis, and unravel metformin's potential in treatment of CRC.

METHODS

We detected inflammasome activation and cell motility following LPS exposure in CRC cell lines. Glycolysis analysis was performed, and the key glycolytic rate-limiting enzymes were detected. Dual-luciferase reporter gene assay, co-immunoprecipitation, chromatin immunoprecipitation (ChIP) analysis, and ChIP-reChIP assay were performed to identify the specific mechanisms of LPS on glycolysis. Mouse metastasis models were used to determine the effects of LPS and metformin on metastasis. Correlation analysis of the expression of various molecules was performed in 635 CRC samples from The Cancer Genome Atlas and 83 CRC samples from our lab.

RESULTS

LPS activates caspase-1 through NF-κB and upregulates the expression of Snail and HK3 depending on caspase-1 activation. LPS potentiates migration and invasion depending on accelerated glycolysis, which could be reversed by knockdown of glycolytic rate-limiting enzyme HK3. Nuclear Snail is upregulated by NF-κB under LPS treatment and then forms a complex with NF-κB, then directly binds to the HK3 promoter region to upregulate the expression of HK3. Metformin suppresses the NF-κB/Snail/HK3 signaling axis that is activated by LPS and then inhibits LPS-induced metastasis. In vivo, LPS-treated cells form more metastasis in the lungs of mice, and metformin completely reverses this effect of LPS.

CONCLUSION

LPS activates inflammasomes in cancer cells through NF-κB and promotes metastasis through glycolysis enhanced by the NF-κB/Snail/HK3 signaling pathway in CRC. Metformin could prevent this effect of LPS.

Targeting Metabolism to Improve the Tumor Microenvironment for Cancer Immunotherapy

The growing field of immune metabolism has revealed promising indications for metabolic targets to modulate anti-cancer immunity. Combination therapies involving metabolic inhibitors with immune checkpoint blockade (ICB), chemotherapy, radiation, and/or diet now offer new approaches for cancer therapy. However, it remains uncertain how to best utilize these strategies in the context of the complex tumor microenvironment (TME). Oncogene-driven changes in tumor cell metabolism can impact the TME to limit immune responses and present barriers to cancer therapy. These changes also reveal opportunities to reshape the TME by targeting metabolic pathways to favor immunity. Here we explore current strategies that shift immune cell metabolism to pro-inflammatory states in the TME and highlight a need to better replicate physiologic conditions to select targets, clarify mechanisms, and optimize metabolic inhibitors. Unifying our understanding of these pathways and interactions within the heterogenous TME will be instrumental to advance this promising field and enhance immunotherapy.

The effect of metformin on lung cancer risk and survival in patients with type 2 diabetes mellitus: A meta-analysis

WHAT IS KNOWN AND OBJECTIVE

Metformin has received increasing attention owing to its potential protective effect against cancer. We aimed to summarize evidence regarding the association between metformin and the risk or survival in lung cancer patients with type 2 diabetes.

METHODS

We selected observational studies examining the association between exposure to metformin and the risk or survival in lung cancer. Available publications were searched in PubMed, Cochrane Library, ScienceDirect, Wiley and SpringerLink databases. Meta-analysis was performed with hazard ratios (HRs) and 95% confidence intervals (95% CIs) as effect measures for risk or survival in lung cancer.

RESULTS

Eighteen studies (eight on lung cancer risk and ten on lung cancer survival) were included. Metformin treatment was associated with decreased lung cancer incidence (HR 0.78; 95% CI 0.70-0.86) and increased lung cancer survival (HR 0.65; 95% CI 0.55-0.77). In the subgroup analysis by ethnicity, a significant protective effect of metformin use on lung cancer risk was observed among Asian patients (HR 0.66; 95% CI 0.56-0.76), but not in European patients. On the other hand, the protective effect of metformin use on lung cancer survival was observed in both Asian (HR 0.57; 95% CI 0.49-0.66) and non-Asian (HR 0.79; 95% CI 0.71-0.88) patients. In the subgroup analysis by histology, a protective effect of metformin on lung cancer survival was observed in both non-small-cell lung cancer (HR 0.68; 95% CI 0.54-0.84) and small-cell lung cancer (HR 0.52; 95% CI 0.39-0.69). Funnel plot showed that no significant publication bias existed.

CONCLUSIONS

Our findings demonstrate that metformin is significantly associated with a decreased risk and increased survival in lung cancer.

Metformin revert insulin-induced oxaliplatin resistance by activating mitochondrial apoptosis pathway in human colon cancer HCT116 cells

BACKGROUND

Several studies have suggested that drug resistance in colon cancer patients with diabetes may be associated with long-term insulin administration, which in turn decreases the survival rate. Metformin is a commonly used drug to treat diabetes but has been recently demonstrated to have a potential therapeutic effect on colon cancer. This study aimed to elucidate the underlying mechanism by which metformin reverts insulin-induced oxaliplatin resistance in human colon cancer HCT116 cells.

METHODS

Two colon cancer cell lines (HCT116 and LoVo) were used to verify whether the expression of insulin receptor substrate 1 (IRS-1) could impact the half maximal inhibitory concentration (IC50) of oxaliplatin after chronic insulin treatment. The IC50 of oxaliplatin in both cell lines was measured to identify metformin sensitization to oxaliplatin. The adenosine monophosphate-activated protein kinase (AMPK) inhibitor, namely AMPK small interfering RNA, was used to block AMPK activation to identify critical proteins in the AMPK/Erk signaling pathway. Bcl-2 is a vital antiapoptotic protein involved in the mitochondrial apoptosis pathway. Finally, immunofluorescence and electron microscopy were performed to investigate how metformin affects the ultrastructural integrity of mitochondria.

RESULTS

The IC50 of oxaliplatin in HCT116 cells was noticeably increased. After the cells were treated with metformin, oxaliplatin resistance was reversed. According to the results of the western blotting assay of vital proteins involved in the classical apoptosis pathway, cleaved caspase-9 was noticeably upregulated, suggesting that the mitochondrial apoptosis pathway was activated. These results were verified by imaging of mitochondria using electron microscopy. The AMPK/Erk signaling pathway experiments revealed that the upregulation of Bcl-2 induced by insulin through Erk phosphorylation was inhibited by metformin and that such inhibition could be mitigated by the inhibition of AMPK.

CONCLUSIONS

Insulin-induced oxaliplatin resistance was reversed by metformin-mediated AMPK activation. Accordingly, metformin is likely to sensitize patients with diabetes to chemotherapeutic drugs used to treat colon cancer.