ABSTRACT
Objective@#To predict the tumor neoantigen peptides in hepatocellular carcinoma (HCC), and examine their specific immune effects against the tumor cells without injury to normal cells.@*Methods@#The data of whole-genome sequencing and exome sequencing of HCC tumor and matched non-tumor liver tissues were analyzed to confirm the HCC-associated somatic mutations. Based on the HLA phenotype of the patients, we used NetMHC software to predict the neoantigen epitopes with high binding affinity to their MHC-I molecules. The predicted peptides with mutation sites included were synthesized. GPL10687 platform was applied to examine the gene expression difference between tumor and normal tissues of the selected genes in GSE25097, one of the GEO databases. The quantitative real-time PCR (qRT-qPCR) and immunohistochemistry were used to confirm the expressions in tumors and normal tissues of the selected genes. By using the predicted peptides, we induced the generation of antigen-specific CD8+ cytotoxic T lymphocytes (CTLs) and examined their specific effects against tumor cells.@*Results@#The mutation frequency of TP53 (tumor protein p53) was 40%, and LAMA3 (Laminin Subunit Alpha 3) was 8% in the analyzed HCC tissues. In GSE25097 database, TP53 and LAMA3 mRNA levels in tumors were 1.57±0.02 and 1.37±0.10, which were significantly increased than those in matched no-tumor tissue (0.54±0.01 and 0.36±0.01, P<0.05). The differences of expression levels of TP53 and LAMA3 in tumor and no-tumor tissues were validated by using qRT-qPCR and immunohistochemistry in 10 HCC tissues. The mRNA levels of TP53 and LAMA3 in tumors were 0.24±0.03 and 0.13±0.06, which were significantly elevated than those in matched no-tumor tissue (0.11±0.01 and 0.01±0.01, P<0.05). Among the Chinese population, HLA-A2 and HLA-A11 and HLA-A24 accounted for 70%, representing the major MHC-I molecules. The CTLs induced by predicted peptides showed cytotoxicity to the targets pulsed with mutated peptide, with no effect on the target pulsed with normal peptide and on normal cells.@*Conclusions@#TP53 and LAMA3 existed relative higher mutation frequency in HCC, and expressed higher in tumor tissues. The induced CTLs by predicted peptides derived from mutation-associated protein could specific kill the target cells without injury to normal cells.
ABSTRACT
Objective To explore the clinical significance and treatment regimen of sentinel lymph node(SLN) micrometastases and isolated tumor cell metastasis in breast cancer.Methods Ninety-seven breast cancer patients with sentinel lymph node micrometastases or isolated tumor cell metastasis from January 2013 to December 2015 were retrospectively studied.The patients were assigned to axillary lymph node dissection group (ALND,41 cases) and non axillary lymph node dissection group(non-ALND,56 cases) according to the final surgery mode to the axilla.Disease-free survival(DFS) and overall survival (OS) were compared between the two groups.Results Neither clinico-pathological factors,such as age,tumor size,grade,ER/PR status,HER-2 gene expression,Ki-67 expression and the size of the SLN metastasis,nor the treatment,such as breast surgery,postoperative adjuvant chemotherapy,radiotherapy and hormone therapy were found statistically different between the two groups (P ＞ 0.05).There were 96 patients evaluable with a median follow up of 24 months.The DFS of the ALND and non-ALND group was 97.5％ and 96.6％ (P ＞ 0.05),and the OS was 100％ and 98.2％ (P ＞ 0.05) respectively with no difference between the two groups.There were 2 ispilateral axillary recurrence in the non-ALND group and non in the ALND group.Conclusion Axillary lymph node dissection may be omitted for the breast cancer patients with sentinel lymph node micrometastases and isolated tumor cell metastases.But the postoperative adjuvant systemic treatment should be emphasized.