Comparison of follow-up treatment regimens for colorectal cancer liver metastases without objective response to neoadjuvant chemotherapy: direct surgery or surgery after second-line chemotherapy / 中华外科杂志

Objective: To compare the effect of direct surgery or surgery after second-line chemotherapy for colorectal cancer patients with liver metastases who did not achieve objective remission after neoadjuvant chemotherapy. Methods: A retrospective case cohort study was used. The clinical and pathological data of 107 patients with colorectal cancer liver metastases who did not achieve objective response to neoadjuvant chemotherapy at Department of Hepatobiliary Surgery,Cancer Hospital,Chinese Academy of Medical Sciences from December 2008 to December 2016 were retrospectively collected. There were 71 males and 36 females, median age was 57 years (range: 28 to 79 years). According to the different treatment regimens after neoadjuvant chemotherapy,107 cases were divided into a direct surgery group (direct group,n=65) and an operation after receiving second-line chemotherapy group (second-line group,n=42). The propensity score matching(PSM) of the Logistic regression model was used to match the bilobar distribution of liver metastases and the number of first-line chemotherapy cycles in the two groups of patients. The caliper value was set to 0.10 and the matching ratio was 1∶2. T test, Mann-Whitney U test, χ2 test or Fisher's exat test was used to analyzed the data between the tuo groups, respectively. Survival analysis design was used to investigate the difference in prognosis between the two groups of patients. Results: The follow-up time(M(IQR)) was 56.3(34.3) months (range: 2.1 to 95.0 months),and all patients were followed up. After PSM,there were 28 cases in the direct group and 42 cases in the second-line group, there were no significant differences in whether R0 resection was feasible,blood loss,blood transfusion,postoperative complications and postoperative hospital stay between the two groups (all P>0.05). The 1,3,and 5-year progression-free survival(PFS) rates of the direct group were 40.0%,16.5%,and 11.0%,and the 1,3,and 5-year overall survival(OS) rates were 98.5%,61.2%,and 41.4%,respectively, the second-line group 1,3,5 years PFS rates were 35.7%,14.3%,14.3%,1,3,5-year OS rate were 95.2%,55.1%,44.4%,respectively. The median PFS time of the direct group and the second-line group was 8.5 months and 7.5 months,respectively,and the difference was not statistically significant (P=0.826). The median OS time of the direct group and the second-line group were 33.8 months and 46.9 months,respectively. The difference was not statistically significant(P=0.646).The median PFS time of the direct group and second-line chemotherapy complete remission and partial remission group(CR/PR group) was 10.2 months and 9.1 months,respectively,and the difference was not statistically significant(P=0.669). The median OS time of the direct group and the second-line CR/PR group was 51.0 months and 46.9 months,respectively,and the difference was not statistically significant(P=0.427). The results of survival analysis suggested that major liver resection was an independent prognosis factor for PFS (HR=1.809,95%CI: 1.067 to 3.067,P=0.028) and OS(HR=2.751,95%CI: 1.317 to 5.747,P=0.007). Second-line chemotherapy was not an independent prognostic factor for PFS (HR=0.945, 95%CI:0.570 to 1.567,P=0.828) and OS (HR=0.866,95%CI: 0.468 to 1.602,P=0.646). Conclusions: There is no significant difference in the short-term outcome and long-term prognosis between direct surgery patients and second-line chemotherapy followed by surgery. Second-line chemotherapy is not an independent prognostic factor for colorectal cancer liver metastases patients who fail to achieve objective response after neoadjuvant chemotherapy.

Clinical Characteristics and Mutation Landscape of Chinese Mucosal Melanoma / 中山大学学报(医学科学版)

@#【Objective】 To use next generation sequencing （NGS） for examing 295 gene mutations in Chinese mucosal melanoma，and explore the mutation landscape of Chinese mucosal melanoma for potential therapeutic targets. 【Methods】The specimens were from 25 mucosal melanoma patients from September 2017 to September 2018 in Biotherapy Center，Sun Yat-sen University Cancer Center. Mutations of 295 genes were detected by NGS sequencing in the Department of Molecular Diagnostics in our hospital. 【Results】 The mutation frequency of major driver genes of melanoma was：BRAF 20%（5/25），KIT 20%（5/25），NRAS 12%（3/25），and NF1 8%（2/25），respectively. The most common mutation was an increase copy number in MYC（9/25，36%），followed by an increase in KDR copy number，24%（6/25）. DNA damage repair，cell cycle，PI3K-mTOR，growth factor receptor，MAPK，immune response and WNT/NOTCH related pathways were widely mutated. Mutation rates were 76%（19/25），72%（18/25），56%（14/25），60%（15/25），36%（9/25），28%（7/25），and 24%（6/25），respectively. Multiple therapeutic targets were observed，such as ATM，ATRX，EMSY， FANCI，RAD52，MET，PDGFRA，KDR，FLT4，ALK，ERBB3 and ROS1.【Conclusion】Gene mutations in Chinese mucosal melanoma were different from that of Chinese cutaneous melanoma and that of Caucasians. NGS could provide potential therapeutic targets for the treatment of Chinese mucosal melanoma.

Targeted therapy: resistance and re-sensitization / 癌症

The last two decades have witnessed a paradigm shift from cytotoxic drugs to targeted therapy in medical oncology and pharmaceutical innovation. Inspired by breakthroughs in molecular and cellular biology, a number of novel synthesized chemical compounds and recombinant antibodies have been developed to selectively target oncogenic signaling pathways in a broad array of tumor types. Although targeted therapeutic agents show impressive clinical efficacy and minimized adverse effects compared with traditional treatments, the challenging drug-resistant issue has also emerged to limit their benefits to cancer patients. In this regard, we aim to improve targeted therapy by presenting a systematic framework regarding the drug resistance mechanisms and alternative approaches to re-sensitize cancer cells/tissues therapeutically.

The absence of the ERBB4 hotspot mutations in melanomas in patients from southern China / 癌症

V-erb-a erythroblastic leukemia viral oncogene homolog 4 (ERBB4) has been reported to be somatically mutated in 19% of melanoma cases. To investigate the prevalence of ERBB4 mutations in melanoma patients from southern China, we analyzed 117 formalin-fixed, paraffin-embedded melanoma samples archived in the Sun Yat-sen University Cancer Center. A matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) platform was used to screen for mutations. No ERBB4 hotspot mutations were detected. Our results indicate that ERBB4 mutations may play a limited role in melanomas in China; therefore, targeting the ERBB4 mutation in melanoma patients from southern China may not be a promising strategy.

Chloroquine enhances the cytotoxicity of topotecan by inhibiting autophagy in lung cancer cells / 癌症

Although the anti-malaria drug chloroquine (CQ) has been shown to enhance chemotherapy and radiation sensitivity in clinical trials, the potential mechanisms underlying this enhancement are still unclear. Here, we examined the relevant mechanisms by which the multipotent CQ enhanced the cytotoxicity of topotecan (TPT). The lung cancer cell line A549 was treated with TPT alone or TPT combined with CQ at non-cytotoxic concentrations. Cell viability was assessed using the MTT assay. The percentage of apoptotic cells and the presence of a side population of cells were both determined by flow cytometry. Autophagy and the expression of Bcl-2 family proteins were examined by Western blotting. The accumulation of YFP-LC3 dots and the formation of acidic vesicular organelles were examined by confocal microscopy. CQ sensitized A549 cells to TPT and enhanced TPT-induced apoptosis in a Bcl-2 family protein-independent fashion. CQ inhibited TPT-induced autophagy, which modified the cytotoxicity of TPT. However, CQ failed to modify the transfer of TPT across the cytoplasmic membrane and did not increase lysosomal permeability. This study showed that CQ at non-cytotoxic concentrations potentiated the cytotoxicity of TPT by interfering with autophagy, implying that CQ has significant potential as a chemotherapeutic enhancer.

Adjuvant interferon therapy for malignant melanoma: the debate / 癌症

Based on the results of the Kirkwood high-dose interferon alpha-2b (HDI) adjuvant therapy trial of the Eastern Cooperative Oncology Group 1684, the US Food and Drug Administration (FDA) approved HDI as the postoperative adjuvant therapy for high-risk melanoma. Unfortunately, controversies continue regarding the use of interferon (IFN) as adjuvant therapy for melanoma owing to the inconsistent results of subsequent trials. Numerous trials of adjuvant interferon therapy demonstrated a benefit in terms of relapse-free survival (RFS), but without confirmed significant effect on overall survival (OS). The optimal timing, dose, and type of interferon are not yet defined. Therefore, adjuvant interferon treatment is preferentially applied in the randomized clinical trials in specialized centers. Decisions about the appropriateness of adjuvant interferon alfa-2b treatment for patients should be made on an individual basis, after discussion with the patient, including an explanation of the potential benefits and side effects of interferon therapy. Moreover, we also need to use available regimens reasonably, seek feasible and predictable prognostic factors to serve patients with individualized therapy.

Cloning of A73 gene and its coding sequence analysis / 南方医科大学学报

<p><b>OBJECTIVE</b>To clone A73 gene of Epstein-Barr virus (EBV) and examine the variation of its coding sequence.</p><p><b>METHODS</b>A73 coding sequence (CDS) amplified from 7 patients in nasophryngeal carcinoma (NPC) biopsies by RT-PCR was cloned into pGEM-T-Easy vector to construct the recombinant plasmid, which was subjected to sequence analysis in Gen Bank database using Blast software.</p><p><b>RESULTS</b>A73 gene from nasophryngeal carcinoma was successfully cloned into pGEM-T Easy vector. A locus with conversion of A-->C in A73 was found at CDS 45 nt, located in the exonVB157154 nt, which did not result in an amino acid replacement, and the variation frequency was 7/7.</p><p><b>CONCLUSION</b>There is a point mutation in A73 CDS of EBV isolated from NPC tissue, which might produce NPC-associated polymorphism with possible involvement in the composition of some subtype of EB virus.</p>