Is breast cancer risk associated with alcohol intake before first full-term pregnancy?

Prediagnosis alcohol intake and metachronous cancer risk in cancer survivors: A prospective cohort study

Alcohol consumption is a known cause of cancer, but its role in the etiology of second primary (metachronous) cancer is uncertain. Associations between alcohol intake up until study enrollment (prediagnosis) and risk of metachronous cancer were estimated using 9435 participants in the Melbourne Collaborative Cohort Study who were diagnosed with their first invasive cancer after enrollment (1990-1994). Follow-up was from date of first invasive cancer until diagnosis of metachronous cancer, death or censor date (February 2018), whichever came first. Alcohol intake for 10-year periods from age 20 until decade encompassing baseline using recalled beverage-specific frequency and quantity was used to calculate baseline and lifetime intakes, and group-based intake trajectories. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs), adjusted for potential confounders. After a mean follow-up of 7 years, 1512 metachronous cancers were identified. A 10 g/d increment in prediagnosis lifetime alcohol intake (HR = 1.03, 95% CI = 1.00-1.06; Pvalue = .02) and an intake of ≥60 g/d (HR = 1.32, 95% CI = 1.01-1.73) were associated with increased metachronous cancer risk. We observed positive associations (per 10 g/d increment) for metachronous colorectal (HR = 1.07, 95% CI = 1.00-1.14), upper aero-digestive tract (UADT) (HR = 1.16, 95% CI = 1.00-1.34) and kidney cancer (HR = 1.24, 95% CI = 1.10-1.39). Although these findings were partly explained by effects of smoking, the association for kidney cancer remained unchanged when current smokers or obese individuals were excluded. Alcohol intake trajectories over the life course confirmed associations with metachronous cancer risk. Prediagnosis long-term alcohol intake, and particularly heavy drinking, may increase the risk of metachronous cancer, particularly of the colorectum, UADT and kidney.

Association between Genetic Polymorphisms of miR-1307, miR- 1269, miR-3117 and Breast Cancer Risk in a Sample of South East Iranian Women

INTRODUCTION

MicroRNAs (miRNAs) play an essential role in the susceptibility and development of cancer cells.

OBJECTIVE

Examining the dependency of breast cancer risk with genetic polymorphisms of miR-1307, miR-1269, and miR-3117 in a sample of Iranian women (southeast region).

METHODS

The case-control study consisted of 520 individuals (260 diagnosed BC patients, 260 healthy individuals). The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used for genotyping of miR-1307 rs7911488, miR-1269 rs73239138, and miR-3117 (rs4655646 and rs7512692) polymorphisms.

RESULTS AND CONCLUSION

This study provided evidence that miR-1307 rs7911488 polymorphism significantly reduced the risk of BC in heterozygous AG genotype, as well as dominant (AG+GG) genotype and G allele. A significant correlation was found between dominant (AA+AG) genotype, the A allele and protection against BC due to miR-1269 rs73239138 in the sample of study. In contrast, our findings suggested that AG genotype and G allele of miR-3117 rs4655646 polymorphism could increase BC's susceptibility among the southeastern Iranian females. The miR-3117 rs7512692 variant also increased the risk of BC in codominant, dominant and recessive models, as well as the T allele. The possible dependency of miR-1307, miR-1269, and miR-3117 variants with patients' clinicopathological characteristics and BC was also studied. It was concluded that there is a correlation between miR-3117 rs7512692 variant and tumor grade (p=0.031); also, a correlation between miR-1269 rs73239138 variant and progesterone receptor status (p=0.006). The current investigation revealed that miR-1307, miR-1269, and miR-3117 polymorphisms might play a crucial role in the Iranian population's vulnerability to BC.<br />.

Evaluating the Possible Association between PD-1 (Rs11568821, Rs2227981, Rs2227982) and PD-L1 (Rs4143815, Rs2890658) Polymorphisms and Susceptibility to Breast Cancer in a Sample of Southeast Iranian Women

INTRODUCTION

Programmed cell death-1 (PD-1) and its ligands (PD-L1 and PD-L2) play a critical role as a  regulator of immune-system cells, including T cell, natural killer T (NKT), monocytes, dendritic cells (DC), and B cells.

OBJECTIVE

This study aimed to find a possible association between PD-1 (rs11568821, rs2227981, rs2227982), and PD-L1 (rs4143815, rs2890658) variants and Breast Cancer (BC) risk in a sample of southeast Iranian women.

METHOD

The case-control study consisted of 520 individuals, including 260 histologically confirmed BC patients and 260 non-cancer age-matching healthy women as the control group. The Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) and Tetra-Primer Amplification Refractory Mutation System-Polymerase Chain Reaction (T-ARMS-PCR) methods were used for genotyping of PD-1 (rs11568821, rs2227981, rs2227982), and PD-L1 (rs4143815, rs2890658) polymorphisms.

RESULTS AND CONCLUSION

Our findings indicated that the PD-L1 rs4143815 (G/C) variant meaningfully reduced the risk of BC. However, the PD-L1 rs2890658 variant increased the BC risk in the AC genotype as well as the A allele. Furthermore, we could not find a meaningful association between PD-1 rs11568821, PD-1 rs2227981, PD-1 rs2227982, and BC. Our team examined the possible association between variants and clinicopathological characteristics, including age, size of tumour, lymph node, histology, grade of tumour, estrogen and progesterone receptors status as well as human growth factor receptor 2 (HER2). Our findings demonstrated that PD-L1 rs4143815, PD-L1 rs2890658, PD-1 rs2227982 had a significant association with age. Additionally, we found a significant relation between PD-1 rs2227982 variant and tumour size. Statistical analyzes of PD-1 rs2227981 and PD-1 rs11568821 variants showed a meaningful relation between tumour grade and tumour stage (p=0.006), respectively.<br />.

Glutathione and Transsulfuration in Alcohol-Associated Tissue Injury and Carcinogenesis

Glutathione (GSH) is the most abundant non-protein thiol, attaining cellular concentrations in the millimolar range. GSH functions to protect cells against endogenous and exogenous electrophiles. In addition, GSH serves as a cofactor for the GSH peroxidase family of enzymes which metabolize H₂O₂ as well as lipid peroxides. Through the action of glutathione S-transferase family of enzymes, GSH is conjugated to a variety of electrophilic endogenous compounds and exogenous chemicals, and thereby facilitates their efficient and safe elimination. Through the transsulfuration pathway, GSH biosynthesis is metabolically linked with cellular methylation, which is pivotal for epigenetic gene regulation. Accumulating evidence suggests that the underlying mechanisms of alcohol-associated tissue injury and carcinogenesis involve: (i) generation of the electrophilic metabolite acetaldehyde, (ii) induction of CYP2E1 leading to the formation of reactive oxygen species and pro-carcinogen activation, and (iii) nutritional deficiencies, such as methyl groups, resulting in enhanced susceptibility to cancer development. In this context, clinical and experimental investigations suggest an intimate involvement of GSH and related enzymes in the development of alcohol-induced pathological conditions. The aim of this review is to provide an overview of the GSH biosynthesis, cellular transsulfuration/transmethylation pathways, and their implications in the pathogenesis and treatment of alcohol-related disease and cancer.