Calpain-10 SNP43 and SNP19 polymorphisms and colorectal cancer: a matched case-control study

C1222C Deletion in Exon 8 of ABL1 Is Involved in Carcinogenesis and Cell Cycle Control of Colorectal Cancer Through IRS1/PI3K/Akt Pathway

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers worldwide. ABL1 (c-Abl) is a non-receptor tyrosine kinase, whose role, and molecular mechanism in CRC remain largely unclear. The aim of this study was to elucidate the role of ABL1 to obtain information on colon cancer gene mutation. We analyzed the tissue samples obtained from patients with CRC, CRC cell lines, and the immunodeficient mice. The proliferation, cell cycle, and apoptosis of CRC cells were examined. IPA software was used to analyze the molecules involved in CRC after ABL1 RNA interference. We found ABL1 was highly expressed in CRC tissues and cells. This high expression was associated with the TNM stage of CRC patients. In exon 8 of the ABL1 gene, we identified a novel mutation of C1222C deletion, which was related to the CRC stage. Depletion of ABL1 resulted in the inhibition of proliferation and escalation of apoptosis in two CRC cell lines, SW480, and HCT-116. Our in vivo study also demonstrated that depletion of ABL1 reduced CRC tumor progression. The results of the ingenuity pathway analysis indicated that the expression of 732 genes was upregulated and that of 691 genes was downregulated in mice transplanted with ABL1-downregulated CRC cells, among which we confirmed that depletion of ABL1 inhibited TGF-β1 via IRS1/PI3K/AKT pathway in CRC progression. These findings demonstrated that ABL1 plays an important role and that it can be a potential molecular target for CRC therapy.

Dietary Habits and Breast Cancer Risk: A Hospital-Based Case-Control Study in Chinese Women

PURPOSE

To investigate the relationship between dietary habits and breast cancer (BC) risk in Chinese women.

PATIENTS AND METHODS

We performed a hospital-based matched case-control study that included 654 BC cases and 654 healthy controls matched by age and residence. A qualified structured questionnaire was used to collect detailed sociodemographic factors and information about dietary habits. The odds ratios (ORs) and 95% confidence intervals were calculated with unconditional logistic regression analysis; the patients were grouped according to their estrogen receptor (ER) status and analyzed separately. The propensity score analysis was performed according to different postmenopause status.

RESULTS

ER-negative BC participants with intake of cured foods had increased BC risk (adjusted OR, 2.72, P = .017). Participants diagnosed as having ER-positive BC with intake of grilled foods had increased BC risk compared to those who did not consume such foods (adjusted OR, 2.14, P = .026). After propensity score analysis, fried (OR, 3.19, P = .001) and grilled (OR, 1.77, P = .031) food were considered to be risk factors for BC in premenopausal women; and fried (OR, 1.61, P = .006), grilled (OR, 4.62, P = .001), and smoked foods (OR, 2.28, P = .001) are considered risk factors for BC in postmenopausal women.

CONCLUSION

Chinese women who ate cured, grilled, and fried foods had higher BC risk. Consumption of smoked food might contribute to increased BC risk in Chinese women.

Development and Validation of an Autophagy Score Signature for the Prediction of Post-operative Survival in Colorectal Cancer

Background: Survival rates for Colorectal cancer (CRC) patients who experienced early relapse have usually been relatively low. Our study aims at developing an autophagy signature that could help to detect early relapse cases in CRC.

Methods: Propensity score matching analysis was carried out between patients from the early relapse group and the long-term survival group from GSE39582. For both groups, respectively, global autophagy expression changes were then analyzed to identify the differentially expressed prognostic autophagy related genes by conducting Linear Models for Microarray data method analysis. Then, the multi-gene signature was validated in TCGA and Fudan University Shanghai Cancer Center (FUSCC) cohorts. Time-dependent ROC were used to test the efficiency of this signature feature in predicting the prognosis of CRC patients.

Results: 5 autophagy genes were finally identified to build an early relapse classifier. With specific risk score formula, patients were classified into low- or high-risk group. Time-dependent ROC analyses proved its prognostic accuracy, with AUC 0.841 and 0.803 at 1 and 3 years, respectively. Then, we validated its prognostic value in two external validation series (GSE17538 and GSE33113) and proved that the result is indeed significant irrespective of datasets in two external independent validation cohorts (TCGA and FUSCC cohorts). A nomogram was constructed to guide individualized treatment of patients with CRC.

Conclusions: The identification of robust autophagy-related features can effectively classify CRC patients into groups with low and high risk of early relapse. This signature may be used to help select high-risk CRC patients who require more aggressive treatment interventions.

Insulin resistance reduces sensitivity to Cis-platinum and promotes adhesion, migration and invasion in HepG2 cells

The liver is normally the major site of glucose metabolism in intact organisms and the most important target organ for the action of insulin. It has been widely accepted that insulin resistance (IR) is closely associated with postoperative recurrence of hepatocellular carcinoma (HCC). However, the relationship between IR and drug resistance in liver cancer cells is unclear. In the present study, IR was induced in HepG2 cells via incubation with a high concentration of insulin. Once the insulin-resistant cell line was established, the instability of HepG2/ IR cells was further tested via incubation in insulin-free medium for another 72h. Afterwards, the biological effects of insulin resistance on adhesion, migration, invasion and sensitivity to cis-platinum (DDP) of cells were determined. The results indicated that glucose consumption was reduced in insulin-resistant cells. In addition, the expression of the insulin receptor and glucose transportor-2 was downregulated. Furthermore, HepG2/IR cells displayed markedly enhanced adhesion, migration, and invasion. Most importantly, these cells exhibited a lower sensitivity to DDP. By contrast, HepG2/IR cells exhibited decreased adhesion and invasion after treatment with the insulin sensitizer pioglitazone hydrochloride. The results suggest that IR is closely related to drug resistance as well as adhesion, migration, and invasion in HepG2 cells. These findings may help explain the clinical observation of limited efficacy for chemotherapy on a background of IR, which promotes the invasion and migration of cancer cells.

Interactions between meat intake and genetic variation in relation to colorectal cancer

Meat intake is associated with the risk of colorectal cancer. The objective of this systematic review was to evaluate interactions between meat intake and genetic variation in order to identify biological pathways involved in meat carcinogenesis. We performed a literature search of PubMed and Embase using “interaction”, “meat”, “polymorphisms”, and “colorectal cancer”, and data on meat–gene interactions were extracted. The studies were divided according to whether information on meat intake was collected prospectively or retrospectively. In prospective studies, interactions between meat intake and polymorphisms in PTGS2 (encoding COX-2), ABCB1, IL10, NFKB1, MSH3, XPC (P_int = 0.006, 0.01, 0.04, 0.03, 0.002, 0.01, respectively), but not IL1B, HMOX1, ABCC2, ABCG2, NR1I2 (encoding PXR), NR1H2 (encoding LXR), NAT1, NAT2, MSH6, or MLH1 in relation to CRC were found. Interaction between a polymorphism in XPC and meat was found in one prospective and one case–control study; however, the directions of the risk estimates were opposite. Thus, none of the findings were replicated. The results from this systematic review suggest that genetic variation in the inflammatory response and DNA repair pathway is involved in meat-related colorectal carcinogenesis, whereas no support for the involvement of heme and iron from meat or cooking mutagens was found. Further studies assessing interactions between meat intake and genetic variation in relation to CRC in large well-characterised prospective cohorts with relevant meat exposure are warranted.