Expression of EGFR-mutant proteins and genomic evolution in EGFR-mutant transformed small cell lung cancer

Background

The transformation of epidermal growth factor receptor (EGFR)-mutant lung adenocarcinoma (LUAD) into small cell lung cancer (SCLC) accounts for 3-14% of the resistance mechanism to EGFR tyrosine kinase inhibitors (TKIs). At present, there is no relevant research to explore the dynamic expression of EGFR-mutant proteins and genomic evolution in EGFR-mutant transformed SCLC/neuroendocrine carcinoma (NEC).

Methods

Genetic analysis and protein level analysis by next-generation sequencing (NGS), Whole-exome sequencing (WES) and immunohistochemistry were performed to explore expression of EGFR-mutant proteins and genomic evolution in EGFR-mutant transformed SCLC. The research used three patient-derived organoids (PDOs) to explore the efficacy of combo [chemotherapy (chemo) plus TKI or bevacizumab] treatment. According to the subsequent treatment regimens after SCLC/NEC transformation, 35 patients were divided into chemo (n=21) and combo (n=14) groups.

Results

EGFR L858R and EGFR E746-750 del protein expression by immunohistochemistry was 80.0% (4/5) and 100% (6/6), respectively (P=0.455) in initially-transformed tissues. Meanwhile, EGFR-mutant proteins were expressed in 85.7% (6/7) of dynamic rebiopsy tissues or effusion samples after the first transformation. Then, by the pathway enrichment analysis of tissue and plasma NGS, the EGFR-related pathways were still activated after SCLC/NEC transformation. Moreover, WES analysis revealed that transformed SCLC shared a common clonal origin from the baseline LUAD. The drug sensitivity of three PDOs demonstrated potent anti-cancer activity of EGFR-TKIs plus chemo, compared with chemo or TKI alone. There were significant differences in objective response rate (ORR) between the combo and chemo groups [42.9 % vs. 4.8%, P=0.010, 95% confidence interval (CI): 1.5-145.2]. Furthermore, the median post-transformation progression-free survival (pPFS) was significantly prolonged in the combo group, with 5.4 (95% CI: 3.4-7.4) versus 3.5 (95% CI: 2.7-4.3, P=0.012) months.

Conclusions

EGFR 19del or L858R-mutant proteins could be constantly expressed, and EGFR pathway still existed in EGFR-mutant transformed SCLC/NEC with a common clonal origin from the baseline LUAD. Taking together, these molecular characteristics potentially favored clinical efficacy in transformed SCLC/NEC treated with the combo regimen.

Pathological characteristics and tumour immune microenvironment of lung malignancies with RET rearrangement

BACKGROUND

For patients with lung malignancies with RET rearrangement, the efficacy of immune checkpoint inhibitors is limited. The characteristics of the tumour immune microenvironment (TIME) and molecular pathological features of these patients have not been well elucidated. We aimed to investigate their clinical outcomes and explore characteristics of TIME, using multiplex immunohistochemistry technology (mIHC).

PATIENTS AND METHODS

The pathology and TIME characteristics of 29 patients with lung malignancies with RET rearrangement were retrospectively analysed, and their relationships with clinical efficacy and prognosis were investigated. Gene detection relied on high-throughput sequencing, and TIME detection was based on mIHC.

RESULTS

Of 29 patients, 25(86%) had adenocarcinoma, and the acinar type accounted for the greatest percentage of patients, followed by the solid type, regardless of whether the disease was early or locally advanced and metastatic. In addition, we report a novel KIF5B-RET(k24:R8) rearrangement in pulmonary sarcoma. The density of CD8+ T cells in tumour stroma in early-stage patients was significantly higher than that in locally advanced and metastatic patients (P = 0.014). The proportion of M2 macrophages in tumour stroma was significantly higher than that in tumour parenchyma (P = 0.046). Although the difference was not statistically significant (P = 0.098), patients positive for M2 macrophage infiltration into the tumour parenchyma (≥5%) may have a better prognosis. Seven patients received immunotherapy and disease control rate was 85.7%.

CONCLUSIONS

A novel KIF5B-RET rearrangement variant in pulmonary sarcoma shows similar TIME characteristics to lung cancer. amongst patients with lung malignancies with RET rearrangement, patients with M2 macrophage infiltration into the tumour parenchyma may have a better prognosis, but further studies with larger cohorts are needed.

Health-related quality of life of patients with intermediate hepatocellular carcinoma after liver resection or transcatheter arterial chemoembolization

BACKGROUND

The aim of our present study was to compare quality of life (QoL) between intermediate-stage (BCLC-B) HCC patients who had undergone either liver resection or transcatheter arterial chemoembolization (TACE).

MATERIALS AND METHODS

A total of 102 intermediate-stage HCC patients participated in our study, including 58 who had undergone liver resection and 44 who had undergone TACE. Baseline demographic characteristics, tumor characteristics, and long-term outcomes, such as tumor recurrence, were compared and analyzed. QoL was assessed using the Short Form (SF)-36 health survey questionnaire with the mental and physical component scales (SF-36 MCS and PCS). This questionnaire was filled out at HCC diagnosis and 1, 3, 6, 12, 24 months after surgery.

RESULTS

For the preoperative QoL evaluation, the 8 domains related to QoL were comparable between the two groups. The PCS and MCS scores were significantly decreased in both the TACE and resection groups at1 month after surgery, and this decrease was greater in the resection group. These scores were significantly lower in the resection group compared with the TACE group (P<0.05). However, these differences disappeared at 3 and 6 months following surgery. One year after surgery, the resection group showed much higher PCS scores than the TACE patients (P=0.018), and at 2 years after surgery, the PCS and MCS scores for the resection group were significantly higher than those for the TACE group (P<0.05). Eleven patients (19.0%) in the resection group and 17 (38.6%) in the TACE group suffered HCC recurrence (P<0.05). Univariate and multivariate analyses indicated that tumor recurrence (HR=1.211, 95%CI: 1.086-1.415, P=0.012) was a significant risk factor for poorpostoperative QoL in the HCC patients.

CONCLUSIONS

Due to its effects on reducing HCC recurrence and improving long-term QoL, liver resection should be the first choice for the treatment of patients with intermediate-stage HCC.

[PI3K p85alpha expression and its role in the progression of colorectal cancer]

OBJECTIVE

To investigate the expression of PI3K p85alpha in normal colorectal tissue, colorectal adenoma and primary colorectal carcinoma and explore its significance in the progression of colorectal cancer.

METHODS

The expression of PI3K p85alpha was detected in 116 normal colorectal tissue, colorectal adenoma and primary colorectal carcinoma specimens using immunohistochemical staining, and the relationship between the expression of PI3K p85alpha protein and the clinicopathological factors was analyzed.

RESULTS

The positivity rates of the expression of PI3K p85alpha protein increased gradually in the progression of colorectal cancer and showed significant differences between the tissues (P<0.05). A significant difference was also noted in the positivity rates of the PI3K p85alpha expression in colorectal carcinoma tissues at different Dukes' stages (P<0.05). No obvious correlation was found between PI3K p85alpha expression and the degree of the tumor differentiation.

CONCLUSIONS

Abnormal PI3K p85alpha expression occurs in the progression of colorectal cancer in close relation to the clinical stage, and the PI3K/AKT pathway plays an important role in the progression of colorectal cancer.