PD-L1 and TILs expression and their association with clinicopathological characteristics in Vietnamese women with primary invasive breast cancer.

Tumor-infiltrating lymphocytes (TILs) and programmed death ligand 1 (PD-L1) are promising new factors in the prognosis and prediction of breast cancer patients. Our study evaluated the prevalence of expression of TILs on hematoxylin and eosin (H&E) slides, PD-L1 expression on immunohistochemistry, and their association with clinicopathological characteristics in Vietnamese women with invasive breast cancer. This study was conducted on 216 women with primary invasive breast cancer. The evaluation of TILs on the HE slides was based on the International TILs Working Group 2014 recommendation. PD-L1 protein expression was determined using the Combined Positive Score, the number of tumor cells, lymphocytes, and macrophages stained by PD-L1 divided by the total viable tumor cells multiplied by 100. Based on the cutoff of 11%, the prevalence of TILs expression was 35.6%, of which highly expressed TILs (≥50%) accounted for 15.3%. Postmenopausal women and those who had a body mass index of 25 kg/m2 or greater had a higher odds of having TILs expression. However, patients who had the expression of Ki-67, HER-positive molecular subtype, and triple-negative subtype were more likely to have TILs expression. The prevalence of PD-L1 expression was 30.1%. A significantly higher odds of having PD-L1 was found in patients who had a history of benign breast disease, self-detected tumor and had TILs expression. The expression of TILs and PD-L1 is common in Vietnamese women with invasive breast cancer. Because of the importance of these expressions, routine evaluation to find women who had TILs and PD-L1 is needed so that treatment and prognosis can be optimized. Such routine evaluation can be targeted to those who had a high-risk profile found in this study.

Molecular characteristics of young-onset colorectal cancer in Vietnamese patients.

BACKGROUND: Colorectal cancer (CRC) is one of the most common cancer globally. Understanding the genetic characteristics of CRC is essential for appropriate treatment and genetic counseling. METHODS: The genetic profile of CRC tumor tissues was identified using next-generation sequencing of 17 target genes (MLH1, MSH2, MSH6, PMS2, EPCAM, APC, SMAD4, BMPR1A, MUTYH, STK11, PTEN, TP53, ATM, CDH1, CHEK2, POLE, and POLD1) in a cohort of 101 Vietnamese patients diagnosed with young-onset CRC. Corresponding germline genetic alterations of determined somatic mutations were subsequently confirmed from patients' blood samples. RESULTS: Somatic mutations were determined in 96 out of 101 CRC patients. Two-thirds of the tumors harbored more than two mutations, and the most prevalent mutated genes were TP53 and APC. Among confirmed germline mutations, 10 pathogenic mutations and 11 variants of unknown significance were identified. CONCLUSIONS: Given the burden of CRC and the gradually reducing cost of genetic testing, multigene panel screening can benefit young-onset CRC patients as well as their relatives.

Loss of expression of cyclin d2 by aberrant DNA methylation: a potential biomarker in vietnamese breast cancer patients.

DNA methylation of tumor suppressor gene promoters is the most frequent phenomenon leading to inactivation of function, consequently driving malignant cell transformation. Cyclin D2 is implicated in tumor suppression. In our study, we carried out the MSP assay to evaluation the methylation status at CpG islands in the cyclin D2 promoter in breast cancer cases from the Vietnamese population. The results showed that the frequency of methylation reached 62.1% (59 of 95 breast cancer tumors), but was low in non-cancer specimens at 10% (2 of 20 non-cancer specimens). Additionally, with an RR (relative risk) and OR (odd ratios) of 6.21 and 14.8, DNA hypermethylation of cyclin D2 increased the possibility of malignant transformation. Our results confirmed the cyclin D2 hypermethylation could be used as the potential biomarker which could be applied in prognosis and early diagnosis of Vietnamese breast cancer patients.

BRCA1 promoter hypermethylation signature for early detection of breast cancer in the Vietnamese population.

Breast cancer, a leading cause of death among women in most countries worldwide, is rapidly increasing in incidence in Vietnam. One of biomarkers is the disruption of the genetic material including epigenetic changes like DNA methylation. With the aim of finding hypermethylation at CpG islands of promoter of BRCA1 gene, belonged to the tumor suppressor gene family, as the biomarker for breast cancer in Vietnamese population, sensitive methyl specific PCR (MSP) was carried out on 115 samples including 95 breast cancer specimens and 20 normal breast tissues with other diseases which were obtained from Ho Chi Minh City Medical Hospital, Vietnam. The result indicated that the frequency of BRCA1 hypermethylation reached 82.1% in the cases (p<0.001). In addition, the DNA hypermethylation of this candidate gene increased the possibility to be breast cancer with high incidence via calculated odd ratios (p<0.05). In conclusion, hypermethylation of this candidate gene could be used as the promising biomarker application with Vietnamese breast cancer patients.