Metformin associated with lower mortality in diabetic patients with early stage hepatocellular carcinoma after radiofrequency ablation

Surgical Implications for Nonalcoholic Steatohepatitis-Related Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is an aggressive form of liver cancer that arises in a background of chronic hepatic injury. Metabolic syndrome-associated fatty liver disease (MAFLD) and its severe form, nonalcoholic steatohepatitis (NASH), are increasingly common mechanisms for new HCC cases. NASH-HCC patients are frequently obese and medically complex, posing challenges for clinical management. In this review, we discuss NASH-specific challenges and the associated implications, including benefits of minimally invasive operative approaches in obese patients; the value of y90 as a locoregional therapy; and the roles of weight loss and immunotherapy in disease management. The relevant literature was identified through queries of PubMed, Google Scholar, and clinicaltrials.gov. Provider understanding of clinical nuances specific to NASH-HCC can improve treatment strategy and patient outcomes.

Metformin: A Dual-Role Player in Cancer Treatment and Prevention

Cancer continues to pose a significant global health challenge, as evidenced by the increasing incidence rates and high mortality rates, despite the advancements made in chemotherapy. The emergence of chemoresistance further complicates the effectiveness of treatment. However, there is growing interest in the potential of metformin, a commonly prescribed drug for type 2 diabetes mellitus (T2DM), as an adjuvant chemotherapy agent in cancer treatment. Although the precise mechanism of action of metformin in cancer therapy is not fully understood, it has been found to have pleiotropic effects, including the modulation of metabolic pathways, reduction in inflammation, and the regulation of cellular proliferation. This comprehensive review examines the anticancer properties of metformin, drawing insights from various studies conducted in vitro and in vivo, as well as from clinical trials and observational research. This review discusses the mechanisms of action involving both insulin-dependent and independent pathways, shedding light on the potential of metformin as a therapeutic agent for different types of cancer. Despite promising findings, there are challenges that need to be addressed, such as conflicting outcomes in clinical trials, considerations regarding dosing, and the development of resistance. These challenges highlight the importance of further research to fully harness the therapeutic potential of metformin in cancer treatment. The aims of this review are to provide a contemporary understanding of the role of metformin in cancer therapy and identify areas for future exploration in the pursuit of effective anticancer strategies.

Targeting the Metabolic Paradigms in Cancer and Diabetes

Dysregulated metabolic dynamics are evident in both cancer and diabetes, with metabolic alterations representing a facet of the myriad changes observed in these conditions. This review delves into the commonalities in metabolism between cancer and type 2 diabetes (T2D), focusing specifically on the contrasting roles of oxidative phosphorylation (OXPHOS) and glycolysis as primary energy-generating pathways within cells. Building on earlier research, we explore how a shift towards one pathway over the other serves as a foundational aspect in the development of cancer and T2D. Unlike previous reviews, we posit that this shift may occur in seemingly opposing yet complementary directions, akin to the Yin and Yang concept. These metabolic fluctuations reveal an intricate network of underlying defective signaling pathways, orchestrating the pathogenesis and progression of each disease. The Warburg phenomenon, characterized by the prevalence of aerobic glycolysis over minimal to no OXPHOS, emerges as the predominant metabolic phenotype in cancer. Conversely, in T2D, the prevailing metabolic paradigm has traditionally been perceived in terms of discrete irregularities rather than an OXPHOS-to-glycolysis shift. Throughout T2D pathogenesis, OXPHOS remains consistently heightened due to chronic hyperglycemia or hyperinsulinemia. In advanced insulin resistance and T2D, the metabolic landscape becomes more complex, featuring differential tissue-specific alterations that affect OXPHOS. Recent findings suggest that addressing the metabolic imbalance in both cancer and diabetes could offer an effective treatment strategy. Numerous pharmaceutical and nutritional modalities exhibiting therapeutic effects in both conditions ultimately modulate the OXPHOS-glycolysis axis. Noteworthy nutritional adjuncts, such as alpha-lipoic acid, flavonoids, and glutamine, demonstrate the ability to reprogram metabolism, exerting anti-tumor and anti-diabetic effects. Similarly, pharmacological agents like metformin exhibit therapeutic efficacy in both T2D and cancer. This review discusses the molecular mechanisms underlying these metabolic shifts and explores promising therapeutic strategies aimed at reversing the metabolic imbalance in both disease scenarios.

Challenges and Solutions in the Management of Hepatocellular Carcinoma Associated with Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) has gained attention in the last few years due to its increasing prevalence worldwide becoming a global epidemic. The increasing incidence of NAFLD and the concurrent increase in the number of hepatocellular carcinoma (HCC) cases at a global level is a matter of concern. HCC has several risk factors, of which NAFLD and its associated metabolic disturbances-type 2 diabetes mellitus, obesity, and dyslipidemia-are of great interest due to their accelerating rise in incidence worldwide. There is a high amount of data derived from basic and clinical studies that reveal the molecular pathways that drive NAFLD-associated HCC. Based on these findings, new prevention, surveillance, and treatment strategies are emerging. However, current data on treatment modalities in NAFLD-associated HCC are still scarce, though the results from non-NAFLD HCC studies are promising and could provide a basis for a future research agenda to address NAFLD/NASH patients. Clinicians should carefully assess all the clinical and radiological parameters and establish a prognosis based on the Barcelona Clinic Liver Cancer classification and discuss in a multidisciplinary team the treatment strategy. The specific factors associated with NAFLD-associated HCC which can have a negative impact on survival even in patients with early HCC, such as cardiovascular disease, type 2 diabetes, and obesity, should be taken into consideration. This review aims to discuss the latest recommendations regarding the diagnosis and treatment of NAFLD-associated HCC and the remaining challenges.

Antitumor Activity of Metformin Combined with Locoregional Therapy for Liver Cancer: Evidence and Future Directions

This article aimed to examine the effect of metformin use on improving outcomes after liver-directed therapy in patients with HCC and identify future directions with the adjuvant use of and potential therapeutic agents that operate on similar mechanistic pathways. Databases were queried to identify pertinent articles on metformin's use as an anti-cancer agent in HCC. Eleven studies were included, with five pre-clinical and six clinical studies. The mean overall survival (OS) and progression-free survival were both higher in the locoregional therapy (LRT) + metformin-treated groups. The outcome variables, including local tumor recurrence rate, reduction in HCC tumor growth and size, tumor growth, proliferation, migration and invasion of HCC cells, HCC cell apoptosis, DNA damage, and cell cycle arrest, showed favorable outcomes in the LRT + metformin-treated groups compared with LRT alone. This systemic review provides a strong signal that metformin use can improve the tumor response after locoregional therapy. Well-controlled prospective trials will be needed to elucidate the potential antitumor effects of metformin and other mTOR inhibitors.

Non-alcoholic fatty liver disease and diabetes mellitus as growing aetiologies of hepatocellular carcinoma

Obesity-related complications such as non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes (T2D) are well-established risk factors for the development of hepatocellular carcinoma (HCC). This review provides insights into the molecular mechanisms that underlie the role of steatosis, hyperinsulinemia and hepatic inflammation in HCC development and progression. We focus on recent findings linking intracellular pathways and transcription factors that can trigger the reprogramming of hepatic cells. In addition, we highlight the role of enzymes in dysregulated metabolic activity and consequent dysfunctional signalling. Finally, we discuss the potential uses and challenges of novel therapeutic strategies to prevent and treat NAFLD/T2D-associated HCC.

Prognostic role of metformin in diabetes mellitus type 2 patients with hepatocellular carcinoma: A systematic review and meta-analysis

BACKGROUND

Hepatocellular carcinoma (HCC) is among the commonest malignancies associated with significant cancer-related death. The identification of chemo-preventive agents following HCC treatments with the potential to lower the risk of HCC adverse course is intriguing. Metformin, a first-line agent used in the treatment of type 2 diabetes mellitus (T2DM), has been associated with inhibition of HCC growth.

AIM

To determine whether metformin can prevent adverse events (i.e., death, tumor progression, and recurrence) after any HCC treatment in T2DM patients.

METHODS

A systematic review of the published literature was undertaken focused on the role of metformin on outcomes in patients with T2DM and HCC receiving any tumor therapy. A search of the PubMed and Cochrane Central Register of Con-trolled Trials Databases was conducted.

RESULTS

A total of 13 studies (n = 14886 patients) were included in this review. With regard to the risk of death, a decreased risk was reported in cases receiving metformin, although this decrease was not statistically significant [odds ratio (OR) = 0.89, P = 0.42]. When only patients treated with curative strategies were considered, a more marked correlation between metformin and favorable cases was reported (OR = 0.70, P = 0.068). When analyzing palliative treatment, there was no statistical significance in terms of the correlation between metformin and favorable cases (OR = 0.74, P = 0.66). As for the risks of progressive disease and recurrence, no obvious correlation between metformin use and reduced risk was reported. When sub-analyses were performed for patients from different regions, the results for patients from Eastern countries showed a tendency for decreased risk of death in T2DM cases receiving metformin (OR = 0.69, P = 0.17), but the same was not seen in patients from Western countries (OR = 1.19, P = 0.31).

CONCLUSION

Metformin failed to show a marked impact in preventing adverse effects after HCC treatment. A trend was reported in T2DM cases receiving curative therapies in relation to the risk of death, especially in patients from Eastern regions. Great heterogeneity was reported among the different studies. Further large studies are required to definitively clarify the real impact of metformin as a chemopreventive agent for HCC.

Use of Metformin and Survival in Patients with Hepatocellular Carcinoma (HCC) Undergoing Liver Directed Therapy: Analysis of a Nationwide Cancer Registry

BACKGROUND

Examine the association of metformin use and overall survival (OS) in patients with HCC undergoing image-guided liver-directed therapy (LDT): ablation, transarterial chemoembolization (TACE), or Yttrium-90 radioembolization (Y90 RE).

METHODS

Using National Cancer Institute Surveillance, Epidemiology, and End Results registry and Medicare claims databases between 2007 and 2016, we identified patients ≥ 66 years who underwent LDT within 30 days of HCC diagnosis. Patients with liver transplant, surgical resection, and other malignancies were excluded. Metformin use was identified by at least two prescription claims within 6 months before LDT. OS was measured by time between first LDT and death or last Medicare observation. Comparisons were performed between both all and diabetic patients on and not on metformin.

RESULTS

Of 2746 Medicare beneficiaries with HCC undergoing LDT, 1315 (47.9%) had diabetes or diabetes-related complications. Among all and diabetic patients, 433(15.8%) and 402 (30.6%) were on metformin respectively. Median OS was greater for patients on metformin (19.6 months, 95% CI 17.1-23.0) vs those not (16.0 months, 15.0-16.9; p = 0.0238). Patients on metformin had lower risk of death undergoing ablation (HR 0.70; 0.51-0.95; p = 0.0239) and TACE (HR 0.76, 0.66-0.87; p = 0.0001), but not Y90 RE (HR1.22, 0.89-1.69; p = 0.2231). Among diabetics, OS was greater for those on metformin vs those not (HR 0.77, 0.68-0.88; p < 0.0001). Diabetic patients on metformin had longer OS undergoing TACE (HR 0.71, 0.61-0.83; p < 0.0001), but not ablation (HR 0.74, 0.52-1.04; p = 0.0886) or Y90 RE (HR 1.26, 0.87-1.85; p = 0.2217).

CONCLUSION

Metformin use is associated with improved survival in HCC patients undergoing TACE and ablation.

The Emerging Role of Metformin in the Treatment of Hepatocellular Carcinoma: Is There Any Value in Repurposing Metformin for HCC Immunotherapy?

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide. There has been significant progress in understanding the risk factors and epidemiology of HCC during the last few decades, resulting in efficient preventative, diagnostic and treatment strategies. Type 2 diabetes mellitus (T2DM) has been demonstrated to be a major risk factor for developing HCC. Metformin is a widely used hypoglycemic agent for patients with T2DM and has been shown to play a potentially beneficial role in improving the survival of patients with HCC. Experimental and clinical studies evaluating the outcomes of metformin as an antineoplastic drug in the setting of HCC were reviewed. Pre-clinical evidence suggests that metformin may enhance the antitumor effects of immune checkpoint inhibitors (ICIs) and reverse the effector T cells' exhaustion. However, there is still limited clinical evidence regarding the efficacy of metformin in combination with ICIs for the treatment of HCC. We appraised and analyzed in vitro and animal studies that aimed to elucidate the mechanisms of action of metformin, as well as clinical studies that assessed its impact on the survival of HCC patients.

Impact of type 2 diabetes mellitus on the prognosis of patients with hepatocellular carcinoma after laparoscopic liver resection: A multicenter retrospective study

Background

The effect of type 2 diabetes mellitus (T2DM) on survival of patients with hepatocellular carcinoma (HCC) after laparoscopic liver resection (LLR) has not been reported. This study aimed to explore the relationship between preoperative T2DM and long-term prognosis in HCC patients undergoing LLR.

Methods

HCC patients receiving LLR as initial treatment at four cancer centers were retrospectively included in this study. Clinicopathological factors associated with the prognosis of HCC patients were identified using univariate and multivariate Cox regression analysis. Recurrence-free survival (RFS) and overall survival (OS) curves between different cohorts of patients were generated using the Kaplan-Meier method and compared using the log-rank test.

Results

Of 402 HCC patients included, 62 patients had T2DM and 340 patients did not have T2DM. The OS and RFS of patients with T2DM were significantly worse compared to those without T2DM (P = 0.001 and 0.032, respectively). In Cox multivariate analysis, T2DM was identified as an independent risk factors for OS (HR = 2.31, 95% CI = 1.38-3.85, P = 0.001) and RFS (HR = 1.66, 95% CI = 1.08-2.55, P = 0.020).

Conclusions

Following laparoscopic surgical approach, HCC patients with T2DM had poorer prognoses than those without T2DM. Preoperative T2DM was an independent risk factor for HCC patients. Thus, patients with concurrent HCC and T2DM should be closely monitored after LLR.

Prevalence and Specific Manifestations of Non-alcoholic Fatty Liver Disease (NAFLD) and Diabetes Mellitus Type 2 Association in a Moroccan Population: A Cross-sectional Study

OBJECTIVE: Non-alcoholic fatty liver disease (NAFLD) is recognized as a common cause of chronic liver disease worldwide. Its association with type 2 diabetes mellitus (T2DM) is known to increase the risk of degenerative complications of diabetes and the likelihood of developing severe hepatic injuries. The objective of this study was to assess the prevalence of NAFLD and to describe the characteristics of its association with T2DM. METHODS: This was a descriptive analytical study, involving patients with T2DM with no history of alcohol consumption, viral hepatitis, hepatotoxic medications, or other chronic liver diseases. The patients underwent an investigation of NAFLD including abdominal ultrasound, non-invasive biomarkers of liver fibrosis, elastography and ultrasound-guided liver biopsy. RESULTS: We collected data from 180 patients with a mean age of 59.3 ± 10.9 years with strong female predominance. The mean duration of diabetes progression was 9.2 ± 7.3 years. Hepatic sonography showed signs of NAFLD in 45.6% of cases. Non-invasive hepatic biomarkers indicated significant fibrosis in 18.3% of cases. Overall, 21% of patients underwent an elastography evaluation, revealing severe fibrosis or cirrhosis in 15.4% of patients. The diagnosis of NASH (Non-alcoholic steatohepatitis) was confirmed histologically in 3 patients. The overall prevalence of NAFLD was 45.6%. Patients with NAFLD had a statistically significant incidence of obesity, metabolic syndrome, hypertension, dyslipidemia, macrovascular complications, and hypertriglyceridemia (p < 0.05). CONCLUSIONS: The combination of NAFLD and T2DM is often found in patients with obesity or metabolic syndrome. The presence of NAFLD can be responsible for increased morbidity and important cardiovascular risks in patients with T2DM.

Metformin administration is associated with enhanced response to transarterial chemoembolization for hepatocellular carcinoma in type 2 diabetes patients

Transarterial chemoembolization (TACE) is often used as a locoregional therapy for early hepatocellular carcinoma (HCC) when local ablation or resection are not feasible, but incomplete response and recurrence are commonly observed. In this study, we sought to determine the association between metformin administration and TACE outcomes for single nodular HCC in patients with type 2 diabetes mellitus (T2DM). The retrospective cohort analysis included 164 T2DM patients with single nodular HCC who underwent TACE as an initial treatment, and 91 were exposed to metformin before and after TACE. Propensity score (PS) matching was used to balance covariates. Logistic regression analysis was used to determine the predictors of tumor response after TACE, and Cox regression analysis assessed independent predictors of local tumor recurrence (LTR) in patients with complete response after TACE. Metformin use was associated with significantly higher objective response rate (ORR) in the overall and PS-matched cohort (79.1% vs. 60.3 and 78.7% vs. 57.5%; p = 0.008 and p = 0.029, respectively). Logistic regression analysis showed that metformin use was an independent predictor of ORR in all and PS-matched patients (odds ratio = 2.65 and 3.06; p = 0.016 and 0.034, respectively). Cox regression analysis showed metformin administration was an independent predictor for lower LTR in all and PS-matched patients (hazard ratio = 0.28 and 0.27; p = 0.001 and 0.007, respectively). Metformin administration is associated with better initial response and lower local recurrence after TACE for single nodular HCC in T2DM.

Impact of diabetes mellitus on the long-term prognosis of patients with hepatocellular carcinoma after hepatectomy

BACKGROUND

The impact of diabetes mellitus (DM) on the survival of patients with hepatocellular carcinoma (HCC) is still unclear. The present study aims to draw a firm conclusion in terms of evaluating the impact of DM on the prognosis of HCC after hepatectomy.

METHODS

The pattern of recurrence for HCC was often stratified into early-stage (<2 years) and late-stage (≥2 years) recurrence. Because the early-stage recurrence was mainly attributed to aggressive tumor pathological characteristics, patients who recurrence or die within 2 years were excluded. Cumulative overall survival (OS) and recurrence-free survival (RFS) were determined by the method of Kaplan-Meier, and the independent risk factors of OS/RFS were determined by Cox regression analysis.

RESULTS

A total of 426 patients were eventually included. The 3- and 5-year OS in patients with and without DM was 83.7%, 55.1%; and 90.9%, 77.4%, respectively. Multivariate analysis showed that DM was an independent risk factor for OS (HR 1.166, 95% CI 1.056-2.036, P = 0.022) and RFS (HR 1.365, 95% CI 1.043-1.787, P = 0.023).

CONCLUSION

DM is an independent risk factor for long-term prognosis in patients with HCC. Patients with DM after hepatectomy for HCC, thus, need to actively control DM and closer follow-up.

NAFLD-driven HCC: Safety and efficacy of current and emerging treatment options

In light of a global rise in obesity and type 2 diabetes, non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) represent an increasingly important underlying aetiology of hepatocellular carcinoma (HCC). HCCs arising from lipotoxicity-mediated chronic inflammation are characterised by several unique features: in contrast to virally driven HCC, up to 50% of NAFLD-HCC occurs in patients without cirrhosis and annual HCC incidence is comparatively low, complicating current surveillance strategies. On average, patients are older and are more frequently diagnosed at an advanced stage. While locoregional treatments are probably equally effective regardless of HCC aetiology, the picture is less clear for systemic therapy. Tyrosine kinase inhibitors are probably equally effective, while there have been initial signals that immune checkpoint inhibitors may be less effective in NAFLD-HCC than in viral HCC. Current international clinical practice guidelines for HCC do not consider aetiology, as there are insufficient data to draw specific conclusions or to recommend aetiology-specific modifications to the current management of patients with HCC. However, in light of the growing relevance of NAFLD-HCC, future clinical trials should assess whether HCC aetiology - and NAFLD/NASH in particular - influence the safety and efficacy of a given treatment.

Transarterial chemoembolization combined with metformin improves the prognosis of hepatocellular carcinoma patients with type 2 diabetes

OBJECTIVE

The study aims to investigate the effect of metformin on Hepatocellular carcinoma (HCC) patients with type 2 diabetes mellitus (T2DM) who received transarterial chemoembolization (TACE) for the first time.

METHODS

From January 2016 to December 2019, T2DM patients diagnosed with HCC in Shandong Cancer Hospital and treated with TACE were included in this retrospective study. Overall survival (OS) and Progression-free survival (PFS) were compared between patients treated with metformin and other antidiabetics. Univariate and multivariate Cox regression models were used to evaluate the independent risk factors associated with OS and PFS. And sub-analysis was performed to investigate whether metformin could give a survival advantage in each Barcelona Clinic Liver Cancer (BCLC) stage of HCC. Propensity score matched (PSM) analyses based on patient and tumor characteristics were also conducted.

RESULTS

A total of 123 HCC patients with T2DM underwent TACE, of which 50 (40.65%) received treatment with metformin. For the whole cohort, the median OS (42 vs 32 months, p=0.054) and PFS (12 vs 7 months, P=0.0016) were longer in the metformin group than that in the non-metformin group. Multi-analysis revealed that BCLC stage, BMI (Body Mass Index), and metformin use were independent predictors of OS. Metformin use was independently associated with recurrence. After PSM, 39 matched pairs were identified. The use of metformin was associated with a numerically longer m OS (43 vs 35 months, P=0.183) than the use of other anti-diabetics. And the difference in median PFS (13 vs 7 months, p=0.018) between the metformin group and non-metformin group remained significant.

CONCLUSION

The combination of transarterial chemoembolization and metformin may be associated with better OS and PFS in HCC patients with T2DM.

The effect of metformin usage on survival outcomes for hepatocellular carcinoma patients with type 2 diabetes mellitus after curative therapy

OBJECTIVE

Metformin has attracted more attention from researchers for its newly discovered antitumor effects. A meta-analysis was performed to reveal the efficacy of metformin on overall survival (OS) and recurrence-free survival (RFS) for HCC patients with type 2 diabetes mellitus (T2DM) after curative treatment.

METHODS

Databases including PubMed, the Cochrane Library, Web of Science, CNKI, Wangfang, and Weipu Database up until 31 May 2022 were searched for relevant studies. STATA 13.0 was used to perform the meta-analysis.

RESULTS

A total of six studies involving 5,936 patients were included in our study. The results from the current study revealed that metformin usage can significantly prolong the 3-year [odds ratio (OR) = 1.50, 95% confidence interval (CI): 1.22-1.83, p = 0.000] and 5-year (OR = 1.88, 95% CI: 1.47-2.41, p = 0.000) OS and decrease the 1-year (OR = 1.31, 95% CI: 1.08-1.59, p = 0.007), 3-year (OR = 1.88, 95% CI: 1.48-2.37, p = 0.000), and 5-year (OR = 1.83, 95% CI: 1.40-2.40, p = 0.000) recurrence rates.

CONCLUSION

Metformin treatment significantly prolongs the OS and decreases the recurrence rate for HCC patients with T2DM after curative HCC therapy.

A geroscience perspective on immune resilience and infectious diseases: a potential case for metformin

We are in the midst of the global pandemic. Though acute respiratory coronavirus (SARS-COV2) that leads to COVID-19 infects people of all ages, severe symptoms and mortality occur disproportionately in older adults. Geroscience interventions that target biological aging could decrease risk across multiple age-related diseases and improve outcomes in response to infectious disease. This offers hope for a new host-directed therapeutic approach that could (i) improve outcomes following exposure or shorten treatment regimens; (ii) reduce the chronic pathology associated with the infectious disease and subsequent comorbidity, frailty, and disability; and (iii) promote development of immunological memory that protects against relapse or improves response to vaccination. We review the possibility of this approach by examining available evidence in metformin: a generic drug with a proven safety record that will be used in a large-scale multicenter clinical trial. Though rigorous translational research and clinical trials are needed to test this empirically, metformin may improve host immune defenses and confer protection against long-term health consequences of infectious disease, age-related chronic diseases, and geriatric syndromes.

Repurposing metformin for the treatment of gastrointestinal cancer

Diabetes mellitus type 2 and cancer share many risk factors. The pleiotropic insulin-dependent and insulin-independent effects of metformin might inhibit pathways that are frequently amplified in neoplastic tissue. Particularly, modulation of inflammation, metabolism, and cell cycle arrest are potential therapeutic cancer targets utilized by metformin to boost the anti-cancer effects of chemotherapy. Studies in vitro and in vivo models have demonstrated the potential of metformin as a chemo- and radiosensitizer, besides its chemopreventive and direct therapeutic activity in digestive system (DS) tumors. Hence, these aspects have been considered in many cancer clinical trials. Case-control and cohort studies and associated meta-analyses have evaluated DS cancer risk and metformin usage, especially in colorectal cancer, pancreatic cancer, and hepatocellular carcinoma. Most clinical studies have demonstrated the protective role of metformin in the risk for DS cancers and survival rates. On the other hand, the ability of metformin to enhance the actions of chemotherapy for gastric and biliary cancers is yet to be investigated. This article reviews the current findings on the anti-cancer mechanisms of metformin and its apparatus from pre-clinical and ongoing studies in DS malignancies.

Impact of metformin use on the recurrence of hepatocellular carcinoma after initial liver resection in diabetic patients

Background

Metformin is proposed to have chemopreventive effect of various cancer currently. However, the anti-cancer effect of metformin for diabetic patients with hepatocellular carcinoma (HCC) undergoing liver resection remains unclear. The aim of our cohort study was to assess whether metformin influence the recurrence of HCC.

Methods

We retrospectively enrolled 857 HCC patients who received primary resection from April 2001 to June 2016. 222 patients were diagnosed with diabetes mellitus (DM) from medical record. Factors influence the overall survival (OS) and recurrence-free survival (RFS) were analyzed by multivariate analysis.

Results

During the follow-up period (mean, 75 months), 471 (54.9%) patients experienced recurrence, and 158 (18.4%) patients died. Multivariate analysis revealed that DM (p = 0.015), elevated AST (p = 0.006), hypoalbuminemia (p = 0.003), tumor number (p = 0.001), tumor size (p < 0.001), vascular invasion (p <0.001), high Ishak fibrosis score (p <0.001), hepatitis B (p = 0.014), hepatitis C (p = 0.001) were independent predictors for RFS. In diabetic patients, only HbA1c>9% (p = 0.033), hypoalbuminemia (p = 0.030) and vascular invasion (p = 0.001) were independent risk factors for HCC recurrence; but the metformin use revealed no significance on recurrence. DM is a risk factor of HCC recurrence after resection. Adequate DM control can reduce the recurrence of HCC. However, the use of metformin does not reduce the risk of HCC recurrence in diabetic patient after initial resection. Hence, metformin may not have protective influences on HCC recurrence in diabetic patients who undergo initial liver resection.

Hepatocellular carcinoma in non-alcoholic fatty liver disease-a review of an emerging challenge facing clinicians

Importance

Non-alcoholic fatty liver disease (NAFLD) is a rapidly growing cause of chronic liver disease and is becoming a leading cause of hepatocellular carcinoma (HCC) in many developed countries. This presents major challenges for the surveillance, diagnosis and treatment of HCC.

Objective

To discuss the clinical challenges faced by clinicians in managing the rising number of NAFLD-HCC cases.

Evidence Review

MEDLINE, PubMed and Embase databases were searched using the keywords; NAFLD, HCC, surveillance, hepatectomy, liver transplantation, percutaneous ablation, transarterial chemoembolization (TACE), selective internal radiotherapy treatment (SIRT) and sorafenib. Relevant clinical studies were included.

Findings

Current HCC surveillance programmes are inadequate because they only screen for HCC in patients with cirrhosis, whereas in NAFLD a significant proportion of HCC develops in the absence of cirrhosis. Consequently NAFLD patients often present with a more advanced stage of HCC, with a poorer prognosis. NAFLD-HCC patients also tend to be older and to have more co-morbidities compared to HCC of other etiologies. This limits the use of curative treatments such as liver resection and orthotopic liver transplantation (OLT). Evidence suggests that although NAFLD-HCC patients who undergo liver resection or OLT have worse perioperative and short-term outcomes, overall long-term survival is comparable to HCC of other etiologies. This highlights the importance of careful patient selection, pre-habilitation and perioperative planning for NAFLD-HCC patients being considered for surgical treatment. Careful consideration is also important for non-surgical treatments, although the evidence supporting treatment selection is frequently lacking, as these patients tend to be poorly represented in clinical trials. Locoregional therapies such as percutaneous ablation and TACE may be less well tolerated and less effective in NAFLD patients with obesity or diabetes. The tyrosine kinase inhibitor sorafenib may also be less effective.

Conclusions and Relevance

This review highlights how international guidelines, for which NAFLD traditionally has made up a small part of the evidence base, may not be appropriate for all NAFLD-HCC patients. Future guidelines need to reflect the changing landscape of HCC, by making specific recommendations for the management of NAFLD-HCC.

Survival advantage associated with metformin usage in hepatocellular carcinoma patients with diabetes mellitus receiving radical resection: a propensity score matching analysis

BACKGROUND

Metformin is associated with improved survival among hepatocellular carcinoma (HCC) patients with diabetes mellitus. However, the role of metformin in the survival of hepatitis B virus (HBV)-related HCC patients with diabetes mellitus after radical resection is unclear, so this study aimed to assess the effects of metformin on the clinical outcomes of patients who received radical resection for HCC.

PATIENTS AND METHODS

A total of 250 HCC patients (30-78 years old) diagnosed with diabetes mellitus were selected between 2000 and 2013 from the First Affiliated Hospital of Nanchang University and the Eastern Hepatobiliary Surgery Hospital in China. Patients were divided into the metformin group (n = 66) and the nonmetformin group (n = 184). A propensity score matching analysis was performed to evaluate the effect of metformin in patients receiving radical resection for HCC.

RESULTS

In the propensity score-matched cohort (n = 176), the overall survival (OS) in the metformin group at 1, 3, and 5 years was significantly higher than in the nonmetformin group (P = 0.002), and a similar treatment effect was observed for disease-free survival (DFS) (P = 0.030). The adjusted Cox proportional hazards model showed that metformin usage significantly improved OS [hazard ratio: 0.558, 95% confidence interval (CI): 0.385-0.810].

CONCLUSIONS

Metformin is associated with satisfactory clinical outcomes among HBV-related HCC patients with diabetes mellitus after radical resection. The use of metformin could significantly improve the OS and reduce the risk of HCC recurrence in patients after radical resection. A prospective controlled study is recommended to verify the metformin effect and explore its possible mechanisms.

Meta-analysis: The efficacy of metformin and other anti-hyperglycemic agents in prolonging the survival of hepatocellular carcinoma patients with type 2 diabetes

INTRODUCTION

This study aimed to compare the therapeutic efficacy of metformin and other anti-hyperglycemic agents in hepatocellular carcinoma (HCC) patients with type 2 diabetes (T2D).

MATERIALS

A systematic electronic search on keywords including HCC and different anti-hyperglycemic agents was performed through electronic databases including Medline and EMBASE. The primary outcome was the overall survival (OS). The secondary outcomes were the recurrence-free survival (RFS) and progression-free survival (PFS).

RESULTS

Six retrospective cohort studies were included for analysis: Four studies with curative treatment for HCC (618 patients with metformin and 532 patients with other anti-hyperglycemic agents) and two studies with non-curative treatment for HCC (92 patients with metformin and 57 patients with other anti-hyperglycemic agents). Treatment with metformin was associated with significantly longer OS (OR1yr=2.62, 95%CI: 1.76-3.90; OR3yr=3.14, 95%CI: 2.33-4.24; OR5yr=3.31, 95%CI: 2.39-4.59, all P<0.00001) and RFS (OR1yr=2.52, 95%CI: 1.84-3.44; OR3yr=2.87, 95%CI: 2.15-3.84; all P<0.00001; and OR5yr=2.26, 95%CI: 0.94-5.45, P=0.07) rates vs. those of other anti-hyperglycemic agents after curative therapies for HCC. However, both of the two studies reported that following non-curative HCC treatment, there were no significant differences in the OS and PFS rates between the metformin and non-metformin groups (I2>50%).

CONCLUSIONS

Metformin significantly prolonged the survival of HCC patients with T2D after the curative treatment of HCC. However, the efficacy of metformin needs to be further determined after non-curative therapies for HCC patients with T2D.

Systemic hypoxia potentiates anti-tumor effects of metformin in hepatocellular carcinoma in mice

Local hypoxia is a universal phenomenon in most solid tumors. The role of local hypoxia in the tumor microenvironment and cancer growth and metastasis has been well established. However, the effect of acute systemic hypoxia (exposing the whole body to 10% O2 environment) on cancer has not yet been investigated. In this study, we investigated the potential effects of acute systemic hypoxia itself and in combination with metformin on hepatocellular carcinoma (HCC) growth and metastasis in a mouse model of HCC. Acute systemic hypoxia significantly decreased tumor volume and weight in H22 tumor-bearing mice. Interestingly, the combined treatment of acute systemic hypoxia and metformin showed a more pronounced effect in reducing tumor volume and weight. Moreover, acute systemic hypoxia and metformin in combination had a potent inhibitory effect on tumor progression. More importantly, the expressions of hypoxia response genes including hypoxia-inducible factor-1 α, vascular endothelial growth factor, and matrix metalloproteinase 2 were significantly decreased in the tumor tissues with combination treatment. Our study demonstrated that acute systemic hypoxia repressed tumor progression of the HCC and potentiated the anti-tumor activities of metformin. This study supports that combination of systemic hypoxia and metformin treatment may represent a novel strategy for HCC.

Independent and Joint Use of Statins and Metformin by Elderly Patients With Diabetes and Overall Survival Following HCC Diagnosis

GOAL

To investigate associations of prediagnosis and postdiagnosis use of statins and metformin on overall survival of patients with diabetes who later developed HCC.

BACKGROUND

Statins and metformin have received considerable interest as potential chemopreventive agents against hepatocellular carcinoma (HCC) development in individuals with type 2 diabetes mellitus (T2DM); however, their impact on overall survival of patients with T2DM who later develop HCC (diabetic HCC patients) is unclear.

STUDY

Data on 2499 elderly diabetic HCC patients obtained from the SEER-Medicare program (2009 to 2013) were analyzed. Patients were categorized based on use of statins only, metformin only, both, or neither (reference for all comparisons). The patients were further categorized based on: (1) metformin dose: ≤1500 or >1500 mg/d; (2) statins functional form: hydrophilic (pravastatin and rosuvastatin) or lipophilic (atorvastatin, fluvastatin, lovastatin, and simvastatin); (3) statins potency: high (atorvastatin, rosuvastatin, and simvastatin) or low (fluvastatin, lovastatin, and pravastatin); and (4) individual statins type. Multivariable-adjusted hazard ratios (HR) and 95% confidence intervals (CIs) were calculated using Cox proportional hazard models.

RESULTS

Prediagnosis use of metformin dose ≤1500 mg/d was associated with lower risk of death after HCC diagnosis in patients with T2DM (HR, 0.72; 95% CI, 0.58-0.91), adjusting for postdiagnosis metformin dose, diabetes severity, Charlson comorbidity index, tumor characteristics, and other relevant factors. No association was found for prediagnosis metformin dose >1500 mg/d or postdiagnosis metformin use. Further, no association was found for either prediagnosis or postdiagnosis statins use.

CONCLUSIONS

Prediagnosis use of metformin dose ≤1500 mg/d is associated with longer overall survival of elderly diabetic HCC patients.

Validation of the Survival Benefits of Metformin in Middle Eastern Patients With Type II Diabetes Mellitus and Colorectal Cancer

Purpose

Epidemiologic data from several populations suggest that metformin may decrease cancer risk and mortality in patients with colorectal cancer (CRC) and type II diabetes mellitus (DM). Although type II DM and CRC are major health problems in the Middle East, no investigations have been performed to test the effect metformin has on the outcome of patients with type II DM and CRC who are also treated with metformin.

Materials and Methods

We retrospectively reviewed the medical records of 1,902 patients diagnosed with CRC at King Hussein Cancer Center between January 2004 and December 2012, and identified 349 patients (18%) with type II DM; we censored the data of 28 patients because their antidiabetic medications were unknown. We then categorized these 321 patients into two groups: 192 patients treated with metformin (group A) and 129 patients treated with other antidiabetic medications (group B).

Results

Group A patients had significantly longer overall survival (89 months; 95% CI, 66 to 112 months) and progression-free survival (47 months; 95% CI, 15 to 79 months) than group B patients (overall survival: 36 months; 95% CI, 24 to 48 months; P ≤ .001; progression-free survival: 21 months; 95% CI, 13 to 29 months; P = .016). After adjustment for age, sex, body mass index, aspirin use, anticholesterol treatment, and CRC stage, group A patients had a 40% reduction in mortality (hazard ratio, 0.58; 95% CI, 0.4% to 0.85%; P = .005).

Conclusion

Our results support findings from other populations that patients with diabetes and CRC who are also treated with metformin have better outcomes than those treated with other antidiabetic medications.

Teaching an old drug new tricks: repositioning strategies for spinal muscular atrophy

Spinal muscular atrophy (SMA) is a childhood disorder caused by loss of the SMN gene. Pathological hallmarks are spinal cord motor neuron death, neuromuscular junction dysfunction and muscle atrophy. The first SMN genetic therapy was recently approved and other SMN-dependent treatments are not far behind. However, not all SMA patients will reap their maximal benefit due to limited accessibility, high costs and differential effects depending on timing of administration and disease severity. The repurposing of commercially available drugs is an interesting strategy to ensure more rapid and less expensive access to new treatments. In this mini-review, we will discuss the potential and relevance of repositioning drugs currently used for neurodegenerative, neuromuscular and muscle disorders for SMA.

Treatment with metformin is associated with a prolonged survival in patients with hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most lethal cancers. Nutrition- and life style-associated risk factors are increasingly prevalent. Metformin, the mainstay of type 2 diabetes mellitus (T2DM)-treatment, reduces the risk of hepatocarcinogenesis. However, its influence on the prognosis of patients with HCC has not been investigated on a large scale, yet.

METHODS

Five thousand and ninety-three patients treated for HCC between 2000 and 2016 at three referral centres were included in this retrospective multicentre study. The aim of this study was to assess whether treatment with metformin for T2DM is associated with a prolonged overall survival (OS) in patients diagnosed with HCC.

RESULTS

Among 5093 patients with HCC, 1917 patients (37.6%) were diagnosed with T2DM, of which 338 (17.6%) received treatment with metformin. Compared to diabetic patients not treated with metformin, patients on metformin had a significantly better hepatic function (Child-Pugh-Score A: 69.2% vs 47.4%, P < 0.001) and underwent significantly more often tumour resection (22.1% vs 16.5%, P = 0.024). Patients on metformin had a significantly longer median OS (mOS) compared to diabetic patients not treated with metformin (22 vs 15 months, P = 0.019). The prolongation of survival was most significant in patients treated with surgery. Using a propensity score match (PSM), patients were adjusted for hepatic function and initial therapy. In the matched cohorts, mOS remained significantly longer in metformin-treated patients (22 vs 16 months, P = 0.021). Co-treatment of metformin and sorafenib was associated with a survival disadvantage.

CONCLUSION

Treatment with metformin was associated with an improved survival in patients with T2DM and HCC. This effect was most pronounced in patients at potentially curative tumour stages.

Radiofrequency ablation of hepatocellular carcinoma: a meta-analysis of overall survival and recurrence-free survival

Background and aims

So far, no randomized trial or meta-analysis has been conducted on overall survival (OS) and recurrence-free survival (RFS) factors in patients treated with radiofrequency ablation (RFA) alone. The purpose of this meta-analysis was to evaluate prognostic factors of OS and RFS in patients treated with RFA.

Methods

A primary analysis was planned to evaluate the clinical prognostic factor of OS. RFS was the secondary aim. Thirty-four studies published from 2003 to 2017 were analyzed. They included 11,216 hepatocellular carcinoma patients.

Results

The results showed that Child-Pugh B vs Child-Pugh A (HR =2.32; 95% CI: 2.201-2.69; P<0.0001) and albumin-bilirubin score 1 vs 0 (HR =2.69; 95% CI: 2.10-3.44; P<0.0001) were predictive of poor OS. Tumor size as a continuous variable was not predictive of OS, although it was predictive of OS when we considered the size as a cutoff value (.2 cm vs <2 cm: HR =1.41; 95% CI: 1.23-1.61; P<0.0001; >3 cm vs <3 cm: HR =1.43; 95% CI: 1.17-1.74; P<0.0001) and in presence of >1 nodule (HR =1.59; 95% CI: 1.46-1.74; P<0.0001). Alpha-fetoprotein >20 ng/mL (HR =1.46; 95% CI: 1.25-1.70; P<0.0001) was the only predictive factor of poor prognosis.

Conclusion

Our meta-analysis highlighted that the maximum benefit of RFA in terms of OS and RFS is reached in the presence of Child-Pugh A, albumin-bilirubin score 1, single-nodule tumor sized <2 cm, and alpha-fetoprotein <20 ng/mL.

Nonalcoholic Fatty Liver Disease and Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) and nonalcoholic fatty liver disease (NAFLD) commonly exist together. It has been regarded as a manifestation of the metabolic syndrome. The presentations of NAFLD range from simple steatosis (NAFL), nonalcoholic steatohepatitis (NASH), and cirrhosis. NAFLD has a prevalence of 70% among T2DM patients. Overweight/obesity and insulin resistance (IR) have been strongly linked with NAFLD. Noninvasive assessment and staging of disease are based on clinical parameters such as age, sex, liver function test, platelet count, lipid profile, BMI, and imaging modalities such as USG, transient elastography (TE), and magnetic resonance imaging mass spectroscopy. Such clinical scoring systems and TE are useful in the early detection of NAFLD and predicting fibrosis. The principle behind the management of NAFLD with T2DM involves an indirect effect through improvement in IR and glycemia and thus is used for the treatment of T2DM as well.

Investigating Effect of Rapamycin and Metformin on Angiogenesis in Hepatocellular Carcinoma Cell Line

Purpose: Human hepatocellular carcinoma is one of the most common causes of death in the world. Metformin and rapamycin may decrease the expression of VEGF protein and subsequently angiogenesis. The purpose of this study was to evaluate the effect of these two drugs on expression of VEGF protein and the cell proliferation in the hepatocellular carcinoma cell line (ATCC HB-8065).

Methods: HepG2 was cultured in RPMI-1640 medium at 37°C for 48h as a pre-culture and then treated by different concentrations of metformin (0, 5, 10 and 20 mM) and rapamycin (0, 5, 10 and 20 nM) at different times (12, 24 and 48 h). Cell viability was assessed by the MTT assay. Total RNA was extracted by the Trizol reagent and VEGF gene expression was analyzed by quantitative real-time PCR and was calculated by 2^–ΔCt method. The VEGF protein level was determined by Elisa assay. Finally, Apoptosis index was calculated by DAPI staining.

Results: Metformin and rapamycin significantly decrease cancer cells viability (p<0.05). Rapamycin but not metformin decreases VEGF gene expression in HepG2 cells. Metformin and rapamycin significantly induce cell apoptosis in hepatocellular carcinoma (HCC) cells.

Conclusion: Metformin and rapamycin have an anti-tumor effect on HCC. According to our data rapamycin might have an anti-angiogenesis effect via inhibition of VEGF expression. Our results provide an insight into future clinical strategies to improve chemotherapy outcomes in HCC.

Metformin use improves survival of diabetic liver cancer patients: systematic review and meta-analysis

Metformin has garnered considerable interest as a chemo-preventive and chemo-therapeutic agent given the increased risk of liver cancer among diabetic patients. This work was performed to illustrate the association between metformin use and survival of diabetic liver cancer patients. We conducted a comprehensive literature search of PubMed, Web of Science, Embase, BIOSIS Previews, Cochrane Library from inception to 12 May 2016. Meta-analyses were performed using Stata (version 12.0), with hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) as effect measures. Eleven cohort studies involving 3452 liver cancer patients fulfilled the inclusion criteria. Meta-analyses showed that metformin use was associated with better survival (HR = 0.59; 95% CI, 0.42-0.83; p = 0.002) of liver cancer patients, and the beneficial effect persisted (HR = 0.64; 95% CI, 0.42-0.97; p = 0.035) when the population was restricted to diabetic liver cancer patients. After adjusting for age, etiology, index of tumor severity and treatment of liver cancer, the association between metformin use and better survival of liver cancer patients was stable, pooled HR ranged from 0.47 to 0.57. The results indicated that metformin use improved survival of diabetic liver cancer patients. However, the results should be interpreted with caution given the possibility of residual confounding. Further prospective studies are still needed to confirm the prognostic benefit of metformin use.

Should we undertake surveillance for HCC in patients with NAFLD?

The pandemic of obesity and its related complications is rapidly changing the epidemiology of many types of cancer, including hepatocellular carcinoma (HCC). Non-alcoholic fatty liver disease (NAFLD) is becoming a major cause of HCC, with a steadily rising trend compared to viral or alcohol-induced chronic hepatitis. The much greater prevalence of the underlying liver disease in the general population and the chance of HCC occurrence in non-cirrhotic liver are the most worrisome aspects of HCC in NAFLD. Effective screening programmes are currently hampered by limited knowledge of the pathways of carcinogenesis and a lack of tools able to stratify the risk of HCC in the NAFLD population. Hence, poor surveillance has prevented the development of an adequate treatment for NAFLD-related HCC. Systemic and hepatic molecular mechanisms involved in hepatocarcinogenesis, as well as potential early markers of HCC are being extensively investigated. This review describes the current clinical impact of HCC in NAFLD and discusses the most important unmet needs for its effective management.

The Effect of Metformin on Mortality Among Diabetic Cancer Patients: A Systematic Review and Meta-analysis

BACKGROUND

Most data suggest that cancer patients with diabetes have worse outcomes, which may be reversed with metformin. Metformin might modulate the clinical outcomes of diabetic cancer patients. We performed a systematic review and meta-analysis based on published studies over the past five years to summarize the effects of metformin on diabetic cancer patients.

METHODS

We systematically searched for studies that were published over the past five years. Then, we evaluated these studies for inclusion and extracted the relevant data. The summary risk estimates for the association between metformin treatment and all-cause mortality (ACM) and cancer-specific mortality (CSM) were analyzed using random or fixed-effects models. Stratified analyses by cancer site and country were also conducted.

RESULTS

Based on the 42 studies included in our analysis (37 015 diabetic cancer patients), we found a significant benefit associated with metformin treatment on survival corresponding to 27% and 26% reductions in ACM (hazard ratio [HR] = 0.73, 95% confidence interval [CI] = 0.68 to 0.79, P < .001) and CSM (HR = 0.74, 95% CI = 0.64 to 0.86, P < .001), respectively. The ACM rates for colorectal cancer, endometrial cancer, breast cancer, prostate cancer, and ovarian cancer showed significant benefits associated with metformin treatment in our stratified analyses by cancer site. Stratified analyses by cancer site also showed a significant reduction in CSM for breast cancer. This association between metformin treatment and reduced CSM for diabetic breast cancer patients was also observed in our country subgroup analyses.

CONCLUSIONS

We found an association between metformin exposure and reduced ACM and CSM in diabetic patients with cancer. Our findings suggest that metformin treatment could be an effective treatment option for diabetic cancer patients.

Interplay Between SIRT-3, Metabolism and Its Tumor Suppressor Role in Hepatocellular Carcinoma

Sirtuins (SIRT), first described as nicotinamide adenine dinucleotide (NAD⁺)-dependent type III histone deacetylases, are produced by cells to support in the defense against chronic stress conditions such as metabolic syndromes, neurodegeneration, and cancer. SIRT-3 is one of the most studied members of the mitochondrial sirtuins family. In particular, its involvement in metabolic diseases and its dual role in cancer have been described. In the present review, based on the evidence of SIRT-3 involvement in metabolic dysfunctions, we aimed to provide an insight into the multifaceted role of SIRT-3 in many solid and hematological tumors with a particular focus on hepatocellular carcinoma (HCC). SIRT-3 regulatory effect and involvement in metabolism dysfunctions may have strong implications in HCC development and treatment. Research literature widely reports the relationship between metabolic disorders and HCC development. This evidence suggests a putative bridge role of SIRT-3 between metabolic diseases and HCC. However, further studies are necessary to demonstrate such interconnection.

Drug repurposing in cancer

Cancer is a major health issue worldwide, and the global burden of cancer is expected to increase in the coming years. Whereas the limited success with current therapies has driven huge investments into drug development, the average number of FDA approvals per year has declined since the 1990s. This unmet need for more effective anti-cancer drugs has sparked a growing interest for drug repurposing, i.e. using drugs already approved for other indications to treat cancer. As such, data both from pre-clinical experiments, clinical trials and observational studies have demonstrated anti-tumor efficacy for compounds within a wide range of drug classes other than cancer. Whereas some of them induce cancer cell death or suppress various aspects of cancer cell behavior in established tumors, others may prevent cancer development. Here, we provide an overview of promising candidates for drug repurposing in cancer, as well as studies describing the biological mechanisms underlying their anti-neoplastic effects.

Impact of Individual Components of the Metabolic Syndrome on the Outcome of Patients with Advanced Hepatocellular Carcinoma Treated with Sorafenib

BACKGROUND/AIM

Individual components of the metabolic syndrome (MS) such as obesity or diabetes mellitus impair the prognosis of patients with hepatocellular carcinoma (HCC) following curative treatment approaches or transarterial therapies. The aim of this retrospective study was to assess the impact of these factors on the overall survival (OS) of patients with advanced HCC treated with sorafenib.

METHODS

Univariate and multivariate analyses were performed to assess the impact of individual components of the MS on the OS of 152 consecutive patients with advanced HCC treated with sorafenib.

RESULTS

The presence of overweight/obesity, type 2 diabetes mellitus, hypertension, dyslipidemia, and of the MS itself did not impair the median OS. Multivariate analysis showed that Eastern Cooperative Oncology Group Performance Status ≥1 (hazards ratio [HR] 2.03), presence of macrovascular invasion (HR 1.71), Child-Pugh score B/C (HR 2.19), tumor grading G3 (HR 2.17), no prior HCC treatment (HR 2.34), and the presence of 2 or more out of 5 individual components of the MS (HR 0.65) were independent prognostic factors regarding the median OS.

CONCLUSIONS

Our investigations do not confirm a negative prognostic role of individual components of the MS or the MS itself for patients with advanced HCC treated with sorafenib.

Metformin exhibits the anti-proliferation and anti-invasion effects in hepatocellular carcinoma cells after insufficient radiofrequency ablation

Background

The mechanisms and prevention of progression of hepatocellular carcinoma (HCC) after insufficient radiofrequency ablation (RFA) has been preliminarily investigated, therefore, new strategy needs to be investigated to prevent the process. Whether metformin could be used to inhibit the growth of HCC after insufficient RFA and further prevent the progression of residual HCC remains unclearly.

Methods

MTT assay, colony formation assay and transwell assay were used to observe the cell viability, migration and invasion. Western blot and immunohistochemistry methods were used to observe the expression of proteins. Xenograft model was used to evaluate the growth of HCC cells in vivo.

Results

Metformin inhibited the enhanced proliferation, migration and invasion of HepG2 and SMMC7721 cells after insufficient RFA (named as HepG2-H and SMMC7721-H). Metformin deregulated the expression of p-Akt in HepG2 and SMMC7721 cells after insufficient RFA through AMPK/PTEN pathway. HepG2-H cells also exhibited larger tumor size in vivo. Higher expression of Ki-67 and CD31 and lower expression of E-cadherin were observed in HepG2-H tumors. Metformin blocked the enhanced growth of HepG2 cells in vivo after insufficient RFA. Metformin had no apparent toxicity on nude mice.

Conclusions

Metfromin inhibited the growth of HCC cells after insufficient RFA, and may be used to prevent the progression of HCC after RFA.

Electronic supplementary material

The online version of this article (doi:10.1186/s12935-017-0418-6) contains supplementary material, which is available to authorized users.

Hyperglycemia-induced metabolic compensation inhibits metformin sensitivity in ovarian cancer

Increasing interest in repurposing the diabetic medication metformin for cancer treatment has raised important questions about the translation of promising preclinical findings to therapeutic efficacy, especially in non-diabetic patients. A significant limitation of the findings to date is the use of supraphysiologic metformin doses and hyperglycemic conditions in vitro. Our goals were to determine the impact of hyperglycemia on metformin response and to address the applicability of metformin as a cancer therapeutic in non-diabetic patients. In normoglycemic conditions, lower concentrations of metformin were required to inhibit cell viability, while metformin treatment in hyperglycemic conditions resulted in increased glucose uptake and glycolytic flux, contributing to cell survival. Mechanistically, maintenance of c-Myc expression under conditions of hyperglycemia or via gene amplification facilitated metabolic escape from the effects of metformin. In vivo, treatment of an ovarian cancer mouse model with metformin resulted in greater tumor weight reduction in normoglycemic vs. hyperglycemic mice, with increased c-Myc expression observed in metformin-treated hyperglycemic mice. These findings indicate that hyperglycemia inhibits the anti-cancer effects of metformin in vitro and in vivo. Furthermore, our results suggest that metformin may elicit stronger responses in normoglycemic vs. hyperglycemic patients, highlighting the need for prospective clinical testing in patients without diabetes.

Non-alcoholic fatty liver disease and diabetes

Non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes (T2DM) are common conditions that regularly co-exist and can act synergistically to drive adverse outcomes. The presence of both NAFLD and T2DM increases the likelihood of the development of complications of diabetes (including both macro- and micro- vascular complications) as well as augmenting the risk of more severe NAFLD, including cirrhosis, hepatocellular carcinoma and death. The mainstay of NAFLD management is currently to reduce modifiable metabolic risk. Achieving good glycaemic control and optimising weight loss are pivotal to restricting disease progression. Once cirrhosis has developed, it is necessary to screen for complications and minimise the risk of hepatic decompensation. Therapeutic disease modifying options for patients with NAFLD are currently limited. When diabetes and NAFLD co-exist, there are published data that can help inform the clinician as to the most appropriate oral hypoglycaemic agent or injectable therapy that may improve NAFLD, however most of these data are drawn from observations in retrospective series and there is a paucity of well-designed randomised double blind placebo controlled studies with gold-standard end-points. Furthermore, given the heterogeneity of inclusion criteria and primary outcomes, as well as duration of follow-up, it is difficult to draw robust conclusions that are applicable across the entire spectrum of NAFLD and diabetes. In this review, we have summarised and critically evaluated the available data, with the aim of helping to inform the reader as to the most pertinent issues when managing patients with co-existent NAFLD and T2DM.

Metformin and survival of people with type 2 diabetes and pleural mesothelioma: A population-based retrospective cohort study

OBJECTIVES

This study aimed to investigate the effect of metformin on survival of people with type 2 diabetes and pleural mesothelioma.

MATERIALS AND METHODS

We conducted a retrospective cohort study of people with type 2 diabetes diagnosed with pleural or unspecified mesothelioma between 1993 and 2014 using linked Scottish population-based diabetes and cancer datasets. Kaplan-Meier plots, log-rank tests, and Cox proportional hazards regression models were used to describe the association between use of metformin and all-cause mortality following diagnosis of pleural mesothelioma.

RESULTS

There were 300 people with type 2 diabetes and pleural or unspecified mesothelioma of whom 148 had ever used metformin and 290 died during follow up. The median survival time was 8.8 months and 6.5 months for metformin users and non-users respectively (p=0.37, log-rank test). After adjusting for age, sex, diabetes duration, socio-economic status, and other anti-diabetic medications the hazard ratio for mortality associated with metformin was 0.99 (95% confidence intervals: 0.76-1.28; p=0.92). Similar non-statistically significant associations were obtained in sensitivity analyses based on metformin use in year prior to diagnosis of mesothelioma, use of metformin for more than one year, in people below the mean age at diagnosis of mesothelioma (74 years) and 74 years of age or older, limitation to pleural mesothelioma and following further adjustment for body mass index and smoking.

CONCLUSION

There was no evidence that metformin improved survival among people with type 2 diabetes and pleural mesothelioma or to support trials of metformin in people with mesothelioma.

Association of Metformin Use With Cancer-Specific Mortality in Hepatocellular Carcinoma After Curative Resection: A Nationwide Population-Based Study

Many preclinical reports and retrospective population studies have shown an anticancer effect of metformin in patients with several types of cancer and comorbid type 2 diabetes mellitus (T2DM). In this work, the anticancer effect of metformin was assessed in hepatocellular carcinoma (HCC) patients with T2DM who underwent curative resection.A population-based retrospective cohort design was used. Data were obtained from the National Health Insurance Service and Korea Center Cancer Registry in the Republic of Korea, identifying 5494 patients with newly diagnosed HCC who underwent curative resection between 2005 and 2011. Crude and adjusted hazard ratios (HRs) were calculated using Cox proportional hazard models to estimate effects. In the sensitivity analysis, we excluded patients who started metformin or other oral hypoglycemic agents (OHAs) after HCC diagnosis to control for immortal time bias.From the patient cohort, 751 diabetic patients who were prescribed an OHA were analyzed for HCC-specific mortality and retreatment upon recurrence, comparing 533 patients treated with metformin to 218 patients treated without metformin. In the fully adjusted analyses, metformin users showed a significantly lower risk of HCC-specific mortality (HR 0.38, 95% confidence interval [CI] 0.30-0.49) and retreatment events (HR 0.41, 95% CI 0.33-0.52) compared with metformin nonusers. Risks for HCC-specific mortality were consistently lower among metformin-using groups, excluding patients who started metformin or OHAs after diagnosis.In this large population-based cohort of patients with comorbid HCC and T2DM, treated with curative hepatic resection, metformin use was associated with improvement of HCC-specific mortality and reduced occurrence of retreatment events.

Metformin inhibits the prometastatic effect of sorafenib in hepatocellular carcinoma by upregulating the expression of TIP30

We previously found that a low dose of sorafenib had a prometastatic effect on hepatocellular carcinoma (HCC), which was caused by downregulation of TIP30 expression. More recently, metformin has been shown to have potential as a preventive and therapeutic agent for different cancers, including HCC. This study evaluated whether the combination of sorafenib and metformin is sufficient to revert the expression of TIP30, thereby simultaneously reducing lung metastasis and improving survival. Our data show that the combination of sorafenib and metformin inhibits proliferation and invasion in vitro, prolongs median survival, and reduces lung metastasis of HCC in vivo. This effect is closely associated with the upregulation of TIP30, partly through activating AMP‐activated protein kinase. Thioredoxin, a prometastasis factor, is negatively regulated by TIP30 and plays an essential role during the process of HCC metastasis. Overall, our results suggest that metformin might be a potent enhancer for the treatment of HCC by using sorafenib.

Metformin, an old drug, brings a new era to cancer therapy

Metformin is the most commonly prescribed drug for type 2 diabetes mellitus as it is inexpensive, safe, and efficient in ameliorating hyperglycemia and hyperinsulinemia. Epidemiological and clinical observation studies have shown that metformin use reduces risk of cancer in patients with type 2 diabetes mellitus and improves prognosis and survival rate of the cancer patients. Furthermore, ongoing clinical trials of metformin in cancer therapy are extending to nondiabetic population. Thus, metformin is emerging as an attractive candidate for cancer prevention and treatment. This review summarizes recent progress in studies of metformin use in cancer and discusses the possibility to enhance its efficacy and to prevent cancer metastasis.

Effects of metformin on clinical outcome in diabetic patients with advanced HCC receiving sorafenib

BACKGROUND AND OBJECTIVE

Several studies have reported an association between type 2 diabetes mellitus and hepatocellular carcinoma (HCC). Data from several retrospective studies and meta-analyses have highlighted a reduction of about 50% in the risk of developing HCC in cirrhotic patients treated with metformin for diabetes. The aim of this study was to evaluate the different outcomes of patients who received or did not receive metformin during treatment with sorafenib.

METHODS

We analyzed 93 patients consecutively treated with sorafenib. Forty-two (45.2%) patients were diabetic, of whom 31 were on metformin. Progression-free survival (PFS) and overall survival (OS) were estimated with the Kaplan-Meier method and compared with the log-rank test.

RESULTS

The concomitant use of sorafenib and metformin was associated with a median PFS of 2.6 months (95% CI 1.9-3.3) compared to 5.0 months (95% CI 2.5-8.2) for patients receiving sorafenib alone (p = 0.029). The median OS of patients treated with the combination was 10.4 months (95% CI 3.9-14.4) compared to 15.1 months (95% CI 11.7-17.8) for those who were not given metformin (p = 0.014).

CONCLUSIONS

Our findings could be the result of increased tumor aggressiveness and resistance to sorafenib in metformin-treated patients.

Systematic review: Preventive and therapeutic applications of metformin in liver disease

Metformin, a biguanide derivative, is the most commonly prescribed medication in the treatment of type 2 diabetes mellitus. More recently, the use of metformin has shown potential as a preventive and therapeutic agent for a broad spectrum of conditions, including liver disease and hepatic malignancies. In this systematic review, we critically analyze the literature behind the potential use of metformin across the spectrum of liver disease and malignancies. The PubMed and Ovid MEDLINE databases were searched from 2000 to March 2015, using a combination of relevant text words and MeSH terms: metformin and mammalian target of rapamycin, hepatitis B virus (HBV), hepatitis B virus (HCV), non-alcoholic fatty liver disease (NAFLD), hepatocellular carcinoma (HCC) or cholangiocarcinoma. The search results were evaluated for pertinence to the issue of metformin in liver disease as well as for quality of study design. Metformin has a number of biochemical effects that would suggest a benefit in treating chronic liver diseases, particularly in the context of insulin resistance and inflammation. However, the literature thus far does not support any independent therapeutic role in NAFLD or HCV. Nonetheless, there is Level III evidence for a chemopreventive role in patients with diabetes and chronic liver disease, with decreased incidence of HCC and cholangiocarcinoma. The use of metformin seems to be safe in patients with cirrhosis, and provides a survival benefit. Once hepatic malignancies are already established, metformin does not offer any therapeutic potential. In conclusion, there is insufficient evidence to recommend use of metformin in the adjunctive treatment of chronic liver diseases, including NAFLD and HCV. However, there is good evidence for a chemopreventive role against HCC among patients with diabetes and chronic liver disease, and metformin should be continued in patients even with cirrhosis to provide this benefit.

Anti-tumor effects of metformin in animal models of hepatocellular carcinoma: a systematic review and meta-analysis

BACKGROUND

Several studies have reported that metformin can reduce the risk of hepatocellular carcinoma (HCC) in diabetes patients. However, the direct anti-HCC effects of metformin have hardly been studied in patients, but have been extensively investigated in animal models of HCC. We therefore performed a systematic review and meta-analysis of animal studies evaluating the effects of metformin on HCC.

METHODS

We collected the relevant studies by searching EMBASE, Medline (OvidSP), Web of Science, Scopus, PubMed Publisher, and Google Scholar. Studies were included according to the following inclusion criteria: HCC, animal study, and metformin intervention. Study quality was assessed using SYRCLE's risk of bias tool. A meta-analysis was performed for the outcome measures: tumor growth (tumor volume, weight and size), tumor number and incidence.

RESULTS

The search resulted in 573 references, of which 13 could be included in the review and 12 included in the meta-analysis. The study characteristics of the included studies varied considerably. Two studies used rats, while the others used mice. Only one study used female animals, nine used male, and three studies didn't mention the gender of animals in their experiments. The quality of the included studies was low to moderate based on the assessment of their risk of bias. The meta-analysis showed that metformin significantly inhibited the growth of HCC tumour (SMD -2.20[-2.96,-1.43]; n=16), but no significant effect on the number of tumors (SMD-1.05[-2.13,0.03]; n=5) or the incidence of HCC was observed (RR 0.62[0.33,1.16]; n=6). To investigate the potential sources of significant heterogeneities found in outcome of tumor growth (I2=81%), subgroup analyses of scales of growth measures and of types of animal models used were performed.

CONCLUSION

Metformin appears to have a direct anti-HCC effect in animal models. Although the intrinsic limitations of animal studies, this systematic review could provide an important reference for future preclinical animal trials of good quality and clinical development.

Nonalcoholic Fatty liver disease, diabetes, obesity, and hepatocellular carcinoma

Diabetes and obesity are associated with nonalcoholic fatty liver disease (NAFLD) and an increased incidence of hepatocellular carcinoma (HCC). NAFLD is the commonest cause of chronic liver disease. HCC can develop in NAFLD patients even without cirrhosis, suggesting an association between the metabolic process and HCC and raising a concern that many cancers could be missed given high NAFLD prevalence and screening limitations. The increasing prevalence of these conditions and lack of effective treatments necessitate a better understanding of their connection. This article defines the known interrelationships and common pathways between NAFLD, diabetes, obesity and HCC and possible chemoprevention strategies.