GMI, a Ganoderma microsporum protein, abolishes focal adhesion network to reduce cell migration and metastasis of lung cancer

BACKGROUND

Cancer metastasis is a major cause of cancer-related deaths, emphasizing the urgent need for effective therapies. Although it has been shown that GMI, a fungal protein from Ganoderma microsporum, could suppress primary tumor growth in a wide spectrum of cancer types, it is still unclear whether GMI exhibits anti-metastasis properties, particularly in lung cancers. Further investigation is needed.

AIMS AND OBJECTIVES

The objective of this study is to investigate the potential inhibitory effects of GMI on lung cancer metastasis in vivo. Utilizing systematic and comprehensive approaches, our research aims to elucidate the underlying molecular mechanisms responsible for the anti-metastatic effects.

MATERIALS AND METHODS

In vitro migration and cell adhesion assays addressed the epithelial-to-mesenchymal transition (EMT)-related phenotype. Proteomic and bioinformatic analyses identified the GMI-regulated proteins and cellular responses. GMI-treated LLC1-bearing mice were analyzed using IVIS Spectrum to assess the anti-metastatic effect.

KEY FINDINGS

GMI inhibits EMT as well as cell migration. GMI disrupts cell adhesion and downregulates integrin, resulting in inhibition of phosphorylated FAK. GMI induces macropinocytosis and lysosome-mediated degradation of integrin αv, α5, α6 and β1. GMI downregulates Slug via inhibition of FAK activity, which in turn enhances expressions of epithelial-related markers and decreases cell mobility. Mechanistically, GMI-induced FAK inhibition engenders MDM2 expression and enhances MDM2/p21/Slug complex formation, leading to Slug degradation. GMI treatment reduces the metastatic pulmonary lesion and prolongs the survival of LLC1-bearing mice.

SIGNIFICANCE

Our findings highlight GMI as a promising therapeutic candidate for metastatic lung cancers, offering potential avenues for further research and drug development.

The burden of end-stage osteoarthritis in Australia: a population-based study on the incidence of total knee replacement attributable to overweight/obesity

OBJECTIVES

To determine the risk of total knee replacement (TKR) for primary osteoarthritis (OA) associated with overweight/obesity in the Australian population.

METHODS

This population-based study analyzed 191,723 cases of TKR collected by the Australian Orthopaedic Association National Joint Registry and population data from the Australian Bureau of Statistics. The time-trend change in incidence of TKR relating to BMI was assessed between 2015 and 2018. The influence of obesity on the incidence of TKR in different age and gender groups was determined. The population attributable fraction (PAF) was then calculated to estimate the effect of obesity reduction on TKR incidence.

RESULTS

The greatest increase in incidence of TKR was seen in patients from obese class III. The incidence rate ratio for having a TKR for obesity class III was 28.683 at those aged 18-54 years but was 2.029 at those aged >75 years. Females in obesity class III were 1.7 times more likely to undergo TKR compared to similarly classified males. The PAFs of TKR associated with overweight or obesity was 35%, estimating 14,287 cases of TKR attributable to obesity in 2018. The proportion of TKRs could be reduced by 20% if overweight and obese population move down one category.

CONCLUSIONS

Obesity has resulted in a significant increase in the incidence of TKR in the youngest population in Australia. The impact of obesity is greatest in the young and the female population. Effective strategies to reduce the national obese population could potentially reduce 35% of the TKR, with over 10,000 cases being avoided.

LncRNA CCAT2 enhances cell proliferation via GSK3β/β-catenin signaling pathway in human osteosarcoma

OBJECTIVE

Osteosarcoma (OS) is a kind of malignant bone tumor. The aim of the manuscript is to investigate the clinical significance and the functional effects of long non-coding (lncRNA) colon cancer-associated transcript 2 (CCAT2) in osteosarcoma.

PATIENTS AND METHODS

Expression of CCAT2 was detected by quantitative Real-time PCR (qRT-PCR) in 50 cases of osteosarcoma tissue samples and adjacent normal bone tissues. Kaplan-Meier survival analysis and log-rank test were used to assess the association between CCAT2 expression and prognosis of OS patients. Cell Counting Kit 8 and cell colony formation assays were performed to evaluate cell proliferation. The protein expression of PCNA, p-GSK3β, GSK3β, and β-catenin were analyzed using Western blot analysis.

RESULTS

We demonstrated that lncRNA CCAT2 expression was significantly upregulated in OS tissues compared to adjacent normal bone tissues. Higher lncRNA CCAT2 expression positively associated with larger tumor size, advanced tumor stage and poor overall survival (OS) rate of patients. In vitro, knockdown of lncRNA CCAT2 suppressed cell proliferation and colony formation ability. In contrast, overexpression of lncRNA CCAT2 showed promoting cell proliferation effects in OS. Also, we found that knockdown of lncRNA CCAT2 inhibited GSK3β/β-catenin signaling by reducing p-GSK3β and β-catenin expression, but increasing GSK3β expression.

CONCLUSIONS

Our results showed that CCAT2 is a crucial oncogene in OS and may be a potential therapeutic target of OS.

The impact of prior radiotherapy on fatal complications after self-expandable metallic stents (SEMS) for malignant dysphagia due to esophageal carcinoma

The esophageal stent has been demonstrated to serve as a safe and effective palliative treatment for advanced inoperable esophageal carcinoma. However, the safety of esophageal stents in patients with prior radiotherapy (RT) remains debated. This article aims to investigate the impact of prior RT on the incidence of fatal complications after self-expandable metallic stents for palliation of malignant dysphagia because of esophageal carcinoma. Between January 2007 and July 2010, 93 patients with malignant dysphagia because of esophageal carcinoma underwent placement of self-expandable metallic stents in our hospital. Patients were retrospectively separated into two groups: patients with RT before stent placement (RT group, n=57) and patients with no treatment before stent placement (no RT group, n=35).The median survival after stent placement was 77 days (7-842 days) in the RT group and 246 days (15-878 days) in the no RT group. Improvement in dysphagia score was similar in both groups. The fatal complications included fatal gastrointestinal hemorrhage and uncontrolled pneumonia. The incidence of fatal gastrointestinal hemorrhage and uncontrolled pneumonia were 28.1% and 5.7% (P=0.009), 28.1% and 5.7% (P=0.009), respectively. Logistic regression analysis showed a significant interaction between prior RT and fatal gastrointestinal hemorrhage (relative risk 7.82, 95% confidence interval 1.54-39.61; P=0.013). Mortality of massive hemorrhage was 5.7% (2/35), 0% (0/4), 12.5% (3/24), and 44.8% (13/29), respectively, in patients who received 0, 1Gy∼49Gy, 50Gy∼60Gy, and >60Gy (χ(2) =17.761; P=0.000). Logistic regression analysis disclosed prior RT did not significantly increase the risk of uncontrolled pneumonia (relative risk 1.47, 95% confidence interval 0.21-10.12; P=0.697).