International Journal of Cancer最新文献

Cancer-associated fibroblasts (CAFs) contribute to the progression of lung cancer. Four and a half LIM domain protein-2 (FHL2) is a component of focal adhesion structures. We analyzed the function of FHL2 expressed by CAFs in lung adenocarcinoma. Expression of FHL2 in fibroblast subtypes was investigated using database of single-cell RNA-sequencing of lung cancer tissue. The role of FHL2 in the proliferation and migration of CAFs was assessed. The effects of FHL2 knockout on the migration and invasion of human lung adenocarcinoma cells and tube formation of endothelial cells induced by CAF-conditioned medium (CM) were evaluated. The effect of FHL2 knockout in CAFs on metastasis was determined using a murine orthotopic lung cancer model. The prognostic significance of stromal FHL2 was assessed by immunohistochemistry in human adenocarcinoma specimens. FHL2 is highly expressed in myofibroblasts in cancer tissue. TGF-β1 upregulated FHL2 expression in CAFs and FHL2 knockdown attenuated CAF proliferation. FHL2 knockout reduced CAF induced migration of A110L and H23 human lung adenocarcinoma cell lines, and the induction of tube formation of endothelial cells. FHL2 knockout reduced CAF-induced metastasis of lung adenocarcinomas in an orthotopic model in vivo. The concentration of Osteopontin (OPN) in CM from CAF was downregulated by FHL2 knockout. siRNA silencing and antibody blocking of OPN reduced the pro-migratory effect of CM from CAF on lung cancer cells. In resected lung adenocarcinoma specimens, positive stromal FHL2 expression was significantly associated with higher microvascular density and worse prognosis. In conclusion, FHL2 expression by CAFs enhances the progression of lung adenocarcinoma by promoting angiogenesis and metastasis.

AST-3424 is a novel and highly tumor-selective prodrug. AST-3424 is activated by AKR1C3 to release a toxic bis-alkylating moiety, AST 2660. In this study, we have investigated the essential role of DNA repair in AST-3424 mediated pharmacological activities in vitro and in vivo. We show here that AST-3424 is effective as a single therapeutic agent against cancer cells to induce cytotoxicity, DNA damage, apoptosis and cell cycle arrest at G2 phase in a dose- and AKR1C3-dependent manner in both p53-proficient H460 (RRID:CVCL_0459) and p53-deficient HT-29 cells (RRID:CVCL_0320). The combination of abrogators of G2 checkpoint with AST-3424 was only synergistic in HT-29 but not in H460 cells. The enhanced activity of AST-3424 in HT-29 cells was due to impaired DNA repair ability via the attenuation of cell cycle G2 arrest and reduced RAD51 expression. Furthermore, we utilized a BRCA2 deficient cell line and two PDX models with BRCA deleterious mutations to study the increased activity of AST-3424. The results showed that AST-3424 exhibited enhanced in vitro cytotoxicity and superior and durable in vivo anti-tumor effects in cells deficient of DNA repair protein BRCA2. In summary, we report here that when DNA repair capacity is reduced, the in vitro and in vivo activity of AST-3424 can be further enhanced, thus providing supporting evidence for the further evaluation of AST-3424 in the clinic.

Breast cancer is by far the leading cancer both in terms of incidence and mortality in the Republic of Mauritius, a Small Island Developing State (SIDS). However, few studies assessed its survival by age, stage at diagnosis and molecular subtype. We identified 1399 breast cancer cases newly diagnosed between 2017 and 2020 at the Central Health Laboratory, Victoria Hospital. Cancers were categorized into five molecular subtypes: (1) luminal A, (2) luminal B Her2 negative, (3) luminal B Her2 positive, (4) Her2 enriched and (5) Triple negative. The net 1 and 3-year survival were estimated for different age groups, staging at time of diagnosis and molecular subtype. We also estimated the excess hazards using a multivariate Cox proportional hazards model. While early stage at diagnosis (stage 1 [44.4%] and stage 2 [20.1%]) were most common compared to late presentation (Stage 3 [25.4%] and stage 4 [10.1%]), luminal B Her2 negative (36.7%) was the most frequent molecular subtype. The net 1- and 3-year breast cancer survival rates were 93.9% (92.3-95.4) and 83.4% (80.4-86.4), respectively. Breast cancer three-year survival rates were poorest among the youngest patients (<50 years), 77.1% (70.7-83.5), those diagnosed with stage 4 (28.5% [17.1-39.9]) and cancer with a triple negative molecular subtype (71.3% [63.3-79.3]). Emphasis on a national breast cancer screening programme, down staging breast cancer at diagnosis and systematic molecular subtyping of all breast tissues could be pivotal in improving breast cancer survival outcomes in the Republic of Mauritius.

In most developed countries, both organized screening (OrgS) and opportunistic screening (OppS) coexist. The literature has extensively covered the impact of organized screening on women's survival after breast cancer. However, the impact of opportunistic screening has been less frequently described due to the challenge of identifying the target population. The aim of this study was to describe the net survival and excess mortality hazard (EMH) in each screening group (OrgS, OppS, or No screening) and to determine whether there is an identical social gradient in each groups. Three data sources (cancer registry, screening coordination centers, and National Health Data System [NHDS]) were used to identify the three screening groups. The European Deprivation Index (EDI) defined the level of deprivation. We modeled excess breast cancer mortality hazard and net survival using penalized flexible models. We observed a higher EMH for "No screening" women compared with the other two groups, regardless of level of deprivation and age at diagnosis. A social gradient appeared for each group at different follow-up times and particularly between 2 and 3 years of follow-up for "OrgS" and "OppS" women. Net survival was higher for "OrgS" women than "OppS" women, especially for the oldest women, and regardless of the deprivation level. This study provides new evidence of the impact of OrgS on net survival and excess mortality hazard after breast cancer, compared with opportunistic screening or no screening, and tends to show that OrgS attenuates the social gradient effect.

14-3-3σ functions as an oncogene in colorectal cancer and is associated with therapy resistance. However, the mechanisms underlying these observations are not clear. The results in this report demonstrate that loss of 14-3-3σ in colorectal cancer cells leads to a decrease in tumor formation and increased sensitivity to chemotherapy. The increased sensitivity to chemotherapy is due to a decrease in the expression of UPR pathway genes in the absence of 14-3-3σ. 14-3-3σ promotes expression of the UPR pathway genes by binding to the transcription factor YY1 and preventing the nuclear localization of YY1. YY1, in the absence of 14-3-3σ, shows increased nuclear localization and binds to the promoter of the UPR pathway genes, resulting in decreased gene expression. Similarly, a YY1 mutant that cannot bind to 14-3-3σ also shows increased nuclear localization and is enriched on the promoter of the UPR pathway genes. Finally, inhibition of the UPR pathway with genetic or pharmacological approaches sensitizes colon cancer cells to chemotherapy. Our results identify a novel mechanism by which 14-3-3σ promotes tumor progression and therapy resistance in colorectal cancer by maintaining UPR gene expression.

The therapeutic efficacy of the anticancer drug cisplatin is limited by acquired drug resistance. Cisplatin forms DNA crosslinks, that, if not removed, lead to replication stress. Due to this, the DNA damage response (DDR) gets activated regulating cell cycle arrest, DNA repair, cell death or survival. This makes DDR components promising targets for the development of new therapeutic approaches aiming to overcome acquired drug resistance. To this end, cisplatin-resistant bladder cancer cells were analyzed regarding their sensitivity to combination treatments with selected pharmacological DDR inhibitors. Synergistic cytolethal effects were achieved after combined treatment with low to moderate doses of the non-genotoxic RAD51-inhibitor (RAD51_i) B02 and CHK1-inhibitor (CHK1_i) PF477736. This effect was also found in cisplatin resistant tumor cells of other origin as well as with other RAD51_i and CHK1_i. Combined treatments promoted decelerated replication, S-phase blockage, accumulation of DNA strand breaks, DDR activation and stimulation of apoptotic cell death as compared to mono-treatment, which is independent of the expression of RAD51, CHK1, and PrimPol. Based on these data, we suggest combined inhibition of RAD51 and CHK1 to overcome acquired cisplatin resistance of malignant cells. We propose that the molecular mechanism of this synergistic toxicity relies on a simultaneous inactivation of two key DNA damage tolerance pathways regulating replication fork restart, thereby circumventing the activation of alternative compensatory mechanisms and, in consequence, eventually effectively triggering apoptotic cell death by replication fork collapse.

Gall bladder cancer (GBC) is common among the socioeconomically deprived populations of certain geographical regions. Aflatoxin is a genotoxic hepatocarcinogen, which is recognized to have a role in the pathogenesis of hepatocellular carcinoma. However, the role of aflatoxin in the pathogenesis of GBC is largely unknown. We determined serum AFB1-Lys albumin adduct (AAA) levels as a marker of aflatoxin exposure in the patients with GBC and compared to those without GBC. The relationship of AAA levels to cytogenetic (TP53mutation&HER2/neu amplification) and radiological characteristics of the tumor was assessed. We included GBC cases (n = 51) and non-GBC controls (n = 100). Mean serum AAA levels were higher in the GBC group (n = 51) than those without GBC (n = 100) (26.1 ± 12.2 vs. 13.1 ± 11.9 ng/mL; p < .001). HER2/neu expression was associated with higher AAA levels compared to those with equivocal or negative expression (43.9 ± 3 vs. 28.6 ± 10 vs. 19.3 ± 7 ng/mL; p < .001). Older age (age >50 years) (odds ratio [OR] = 3.2 [CI: 1.3-8.2]; p = .013), positive Helicobacter pylori serology (OR = 5.1 [CI: 1.4-17.8]; p = .012), presence of GS (OR = 5 [CI: 1.5-16.9]; p = .009) and detectable AAA levels (OR = 6.8 [CI: 1.3-35.7]; p = .024) were independent risk factors for the presence of the GBC among all study subjects. Among patients harboring GS, older age (age >50 years) (OR = 4.5 [CI: 1.3-14.9]; p = .015), female gender (OR = 3.8 [CI: 1.2-12.5]; p = .027), presence of multiple GS (OR = 21.9 [CI: 4.8-100.4]; p < .001) and high serum AAA levels (OR = 5.3 [CI: 1.6-17.3]; p = .006) were independent risk factors for the presence of the GBC. Elderly age >50 years (OR = 2.6 [CI: 1.3-5.2]; p = .010) and frequent peanut consumption (OR = 2.3 [CI: 1.1-4.9]; p = .030) were independent risk factors for high serum AAA levels. The current study has implications for the prevention of GBC through the reduction of dietary aflatoxin exposure.

Tumor deposits (TD) are tumor nodules in the lymphatic drainage area of colorectal cancer patients, and they are currently classified in the N category in the TNM classification. However, due to the associated poor prognosis, some small cohort studies suggest that TD belong in the M category. A retrospective study using The Surveillance, Epidemiology, and End Results program (SEER) data was performed in Stages III and IV colon carcinoma (CC) patients to evaluate the prognostic impact of TD. In multivariate analysis, TD have significantly negative effect on survival in both stages (Stage III HR = 1.4 [95% CI 1.4-1.5] and Stage IV HR = 1.3 [95% CI 1.2-1.3]). In Stage III, 5-year overall survival (OS) for patients with TD 49%, whereas it was 64% for patients without TD (p < .001). Additionally, in Stage IV patients without TD, the 5-year OS rates are superior at 21% compared to patients with TD, who show 5-year OS rate of 10% (p < .001). Stage III patients with TD (5-year OS 49%) have a significantly better prognosis compared to Stage IV patients (5-year OS 17%, p < .001). Therefore, despite the previous suggestions, this large scale study (n = 52,332) on outcomes in CC does not support the classification of TD in Stage IV.