Genomic Feature of a Rare Case of Mix Small-Cell and Large-Cell Neuroendocrine Lung Carcinoma: A Case Report.

BACKGROUND: Cases of both of small- (SCLC) and large-cell neuroendocrine lung carcinoma (LCNEC) were rarely reported. Although typical cases are morphologically distinct, the distinction between LCNEC and SCLC is still controversial, with some LCNECs showing close morphologies with SCLC. Here, we reported on a patient who had tumor with a mix of SCLC and LCNEC and uncovered these components' histological and genomic features. CASE PRESENTATION: A 59-year-old man was diagnosed with lung cancer and had resection surgery in our hospital. The H&E and immunohistochemistry staining revealed that the tumor had 30%-35% LCNEC and 65%-70% SCLC cells. The whole-exome sequencing (WES) identified no potentially actionable alteration in the tumor sample but found five alterations all with allele frequency over 90%, including TP53 p.R273H, MYH8 p.Q1814K, SLC17A6 p.W505L, PTPN5 p.M40I, and RB1 p.L267X. The genomic results supported that these two different components shared a similar dominant clonal origin. Furthermore, fluorescence in situ hybridization analysis revealed that the LCNECs have a higher copy number of MET than the SCLC component while without notable difference in the copy number of HER2 and TP53. Chemotherapy with pemetrexed and carboplatin was administrated for two cycles after the surgery. Although the chest CT showed remission in the lung, he was diagnosed with bone metastasis in 1 year later. Then, he received chemotherapy with etoposide and carboplatin but had severe side effect, leading to the discontinuation of the regime. Unfortunately, he returned to the local hospital with supportive care and died shortly after. CONCLUSION: Based on these observations, we proposed that LCNEC and SCLC components in this patient may have a common clonal origin with dual mutations in TP53 and RB1, while the chromosome instability may cause multiple independent conversion that leads to LCNEC or SCLC morphologies.

A model for the impact of FFPE section thickness on gene copy number measurement by FISH.

Fluorescent in situ hybridization (FISH) assays to detect gene amplification such as HER2 or MET in tumors are used for prognosis evaluation and selection of targeted therapies. Although FISH guidelines recommended 4~6 µm FFPE sections, many laboratories use 2~3 µm sections, which is a common practice for H&E staining and immunohistochemistry. A former study concluded that section thickness did not affect FISH results. We found, however, that thinner FFPE sections may lead to false negative results for gene amplification. A mathematic model was constructed and cell-line based controls with known gene copy number were prepared, and the model had a reasonable fit with the experimental data. The model revealed that even when counting the apparently full-sized nuclear images, many of them have partial volumes, which leads to under-estimation of gene copy number. Therefore, improperly thinner sections are prone to give false negative results, and thicker sections give a better approximation to the true value. The discrepancy between this and the former study was discussed. In summary, the model applies generally to FISH/ISH detection of gene copy number, and section thickness is an important parameter to control for precision medicine research, assay development, clinical trials and daily practice in pathology laboratory.

Solanum nigrum polysaccharide inhibits tumor growth in H22-bearing mice through regulation of caspase-3 and bcl-2.

OBJECTIVE: The objective of this study was to investigate the effect of Solanum nigrum polysaccharides (SNPs) on tumor growth in H22 hepatocarcinoma cells bearing mice and explore the mechanism by focusing on the regulation of the expression of caspase-3 and bcl-2. MATERIALS AND METHODS: Totally, 50 mice bearing with H22 cells were randomly divided into five groups: Model group, cyclophosphamide group (CTX, 30 mg/kg), SNP groups with low, medium, and high doses of SNP (30, 60, and 120 mg/kg). Twenty-four hours after inoculation of H22 cells, CTX or SNP were given by gavage once a day for 10 days. The growth of tumor was observed. The tumor inhibition rate, indexes of the spleen and thymus were calculated. The immunohistochemical method was used for the determination of caspase-3 and bcl-2 expression in the tumor tissue. RESULTS: SNP (30, 60, and 120 mg/kg) reduced the average tumor weight compared with that in model group in a dose-dependent manner, and the tumor inhibition rates were 37.73%, 38.24%, and 42.60%, respectively. In addition, SNP dose dependently increased the index of the thymus compared with that of the CTX group. Immunohistochemistry results showed that the protein expression of caspase-3 in SNP groups was higher, but the expression of bcl-2 was lower than that in model group in a dose-dependent manner. CONCLUSION: SNP inhibited the growth of tumor in H22-bearing mice and protected the immune organ. The mechanism underlying the inhibition of tumor might be related to the upregulation of caspase-3 and downregulation of bcl-2.

Lung cancer with concurrent EGFR mutation and ROS1 rearrangement: a case report and review of the literature.

ROS1 rearrangement has recently emerged as a new molecular subtype in non-small cell lung cancer, and is predominantly found in lung adenocarcinomas compared with other oncogenes such as EGFR, KRAS, or ALK. Patients who have both mutations are extremely rare. Here we report a 50-year-old female diagnosed with adenocarcinoma with sarcomatoid differentiation, who was shown to have EGFR and ROS1 mutations. The patient was treated surgically and received three cycles of adjuvant postoperative chemotherapy. In addition, we reviewed the previously reported cases and related literature. This presentation will provide further understanding of the underlying molecular biology and optimal treatment for non-small cell lung cancer patients with more than one driver mutation.

MiR-376a and histone deacetylation 9 form a regulatory circuitry in hepatocellular carcinoma.

BACKGROUND/AIMS: Our previous study has demonstrated that down-regulation of miR-376a might contribute to the development of hepatocellular carcinoma (HCC), but the mechanism underlying this down-regulation remains obscure. METHODS/RESULTS: histone deacetylase (HDAC) inhibitor increased the level of miR-376a in L02 and Huh7 cells by up-regulating the acetylation level of histone 3 at the Maternally expressed 3 (Meg3) differentially methylated region (DMR). Interestingly, HDAC9, a histone deacetylase responsible for deacetylating lysine 18 of histone 3 (H3K18), was identified as the target of miR-376a. In addition, HDAC9 siRNA increased the expression of miR-376a by up-regulating the global histone H3K18 acetylation level, with Meg3 DMR included. Finally, miR-376a and HDAC9 were inversely correlated in HCC. CONCLUSION: HDAC9 plays an important role both as effects and targets of miR-376a.