A case of acute promyelocytic leukemia during gefitinib treatment

Chronic myeloid leukemia during osimertinib treatment in a non-small cell lung cancer patient: A case report

Case summary

A 45-year-old man presented with a 4.0cm × 4.0cm mass in right lower lobe and a right lower lobectomy was performed. The pathological diagnosis from the right lower lobe mass was adenocarcinoma with an EGFR mutation in exon 21 (L858R). He chose osimertinib as postoperative adjuvant treatment. Eight months after the administration of osimertinib, leukocytosis was detected and we diagnosed the patient with chronic myeloid leukemia (CML). After the diagnosis was made, the patient started the treatment of flumatinib immediately, and treatment of osimertinib continued. After one month treatment, leukocytosis was completely relived. The patient was receiving treatment of osimertinib and flumatinib simultaneously with both lung cancer and leukemia well-controlled, and the side effects were tolerable.

Conclusion

Hemogram of non-small cell lung cancer (NSCLC) patients should be carefully monitored during EGFR-TKIs treatment. While there is a potential association between EGFR-TKIs and the development of hematologic abnormalities such as CML, more evidence is needed to clarify whether EGFR-TKIs have a leukemogenic effect. For patients with CML during EGFR-TKIs treatment, osimertinib combined with flumatinib may be an effective treatment modalities and the side effects can be tolerated.

Therapy-related myeloid leukemia during erlotinib treatment in a non-small cell lung cancer patient: A case report

BACKGROUND

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are tolerable drugs used for patients with EGFR-mutant advanced non-small cell lung cancer (NSCLC). Serious adverse reactions are uncommon compared with cytotoxic drugs.

CASE SUMMARY

A 52-year-old man presented with general weakness and cytopenia. He had been taking erlotinib for 11 mo to treat NSCLC. The pathological diagnosis from the right upper lobe mass was adenocarcinoma with an EGFR mutation in exon 21 (L858R). He had previously received paclitaxel/carboplatin, gemcitabin/ vinorelbine chemotherapy, stereotactic radiosurgery for brain metastasis, and whole-brain radiotherapy as treatment for NSCLC. We diagnosed the patient with acute myeloid leukemia (AML). During the induction and consolidation chemotherapy for AML, the erlotinib was discontinued. When complete remission of the AML was achieved, since the lung masses were increased, pemetrexed/ cisplatin for the NSCLC was initiated. After two cycles of chemotherapy, the cytopenia was prolonged. AML relapse occurred with the same karyotype.

CONCLUSION

Therapy-related acute myeloid neoplasm (t-MN) is a rare but fatal late complication. Although a patient may be taking EGFR-TKIs, the possibility of t-MN should be considered. Further studies are needed to determine whether EGFR-TKI usage is a predisposing factor for t-MN.

Lapatinib induces autophagic cell death and differentiation in acute myeloblastic leukemia

Lapatinib is an oral-form dual tyrosine kinase inhibitor of epidermal growth factor receptor (EGFR or ErbB/Her) superfamily members with anticancer activity. In this study, we examined the effects and mechanism of action of lapatinib on several human leukemia cells lines, including acute myeloid leukemia (AML), chronic myeloid leukemia (CML), and acute lymphoblastic leukemia (ALL) cells. We found that lapatinib inhibited the growth of human AML U937, HL-60, NB4, CML KU812, MEG-01, and ALL Jurkat T cells. Among these leukemia cell lines, lapatinib induced apoptosis in HL-60, NB4, and Jurkat cells, but induced nonapoptotic cell death in U937, K562, and MEG-01 cells. Moreover, lapatinib treatment caused autophagic cell death as shown by positive acridine orange staining, the massive formation of vacuoles as seen by electronic microscopy, and the upregulation of LC3-II, ATG5, and ATG7 in AML U937 cells. Furthermore, autophagy inhibitor 3-methyladenine and knockdown of ATG5, ATG7, and Beclin-1 using short hairpin RNA (shRNA) partially rescued lapatinib-induced cell death. In addition, the induction of phagocytosis and ROS production as well as the upregulation of surface markers CD14 and CD68 was detected in lapatinib-treated U937 cells, suggesting the induction of macrophagic differentiation in AML U937 cells by lapatinib. We also noted the synergistic effects of the use of lapatinib and cytotoxic drugs in U937 leukemia cells. These results indicate that lapatinib may have potential for development as a novel antileukemia agent.

Lapatinib induces autophagy, apoptosis and megakaryocytic differentiation in chronic myelogenous leukemia K562 cells

Lapatinib is an oral, small-molecule, dual tyrosine kinase inhibitor of epidermal growth factor receptors (EGFR, or ErbB/Her) in solid tumors. Little is known about the effect of lapatinib on leukemia. Using human chronic myelogenous leukemia (CML) K562 cells as an experimental model, we found that lapatinib simultaneously induced morphological changes resembling apoptosis, autophagy, and megakaryocytic differentiation. Lapatinib-induced apoptosis was accompanied by a decrease in mitochondrial transmembrane potential and was attenuated by the pancaspase inhibitor z-VAD-fmk, indicating a mitochondria-mediated and caspase-dependent pathway. Lapatinib-induced autophagic cell death was verified by LC3-II conversion, and upregulation of Beclin-1. Further, autophagy inhibitor 3-methyladenine as well as autophagy-related proteins Beclin-1 (ATG6), ATG7, and ATG5 shRNA knockdown rescued the cells from lapatinib-induced growth inhibition. A moderate number of lapatinib-treated K562 cells exhibited features of megakaryocytic differentiation. In summary, lapatinib inhibited viability and induced multiple cellular events including apoptosis, autophagic cell death, and megakaryocytic differentiation in human CML K562 cells. This distinct activity of lapatinib against CML cells suggests potential for lapatinib as a therapeutic agent for treatment of CML. Further validation of lapatinib activity in vivo is warranted.