Cetuximab was approved in Japan as the only clinically available molecular targeted drug for the treatment of head and neck cancer. Hypomagnesemia associated with cetuximab is considered one of the most serious adverse events. However, the factors influencing the development of hypomagnesemia are not clear, although the drug was previously approved for the treatment of patients with colorectal cancer. Thus, we studied the factors involved in the development of hypomagnesemia in patients receiving cetuximab therapy for head and neck cancer. Patients' background data and laboratory values before starting cetuximab therapy did not affect the development of hypomagnesemia. Among patients who had never been treated with cisplatin (NT group), 36.4% developed hypomagnesemia. In contrast, all patients who had previously been treated with cisplatin (T group) developed hypomagnesemia (p=0.034). Magnesium is reabsorbed by transient receptor potential subfamily melastatin 6 (TRPM6) in the distal convoluted tubule. The expression level of TRPM6 is controlled by the epidermal growth factor (EGF) pathway. Cetuximab is an EGF receptor inhibitor and reduces the expression of TRPM6. Additionally, recent studies have shown that the expression of TRPM6 is reduced by cisplatin. Therefore, we considered that the serum magnesium level was cumulatively reduced by cetuximab and cisplatin. In conclusion, the T group was more likely to develop hypomagnesemia than the NT group, and therefore the serum magnesium level in the T group requires careful monitoring so that magnesium supplementation can be provided to patients when the level decreases.

In recent years, the incidence of eye disorders due to antineoplastic agents such as S-1 has increased. Eye disorders including visual field defect, visual field impairment, optic neuritis, and visual acuity reduction have been reported as serious adverse effects of oxaliplatin, an agent that is frequently used as a standard therapy for colorectal cancer. However, specific details about these conditions, such as the timing relative to oxaliplatin administration and frequencies at which they appear, remain to be clarified; therefore, we conducted a retrospective analysis of patients with eye disorders due to oxaliplatin in order to obtain evidence that would be useful in routine medical practice. Of the 55 patients who were treated with oxaliplatin in this analysis 10 (18.2%) presented with eye disorders, including blepharoptosis (5 patients, 9.1%), visual field impairment (2 patients, 3.6%), visual acuity reduction (2 patients, 3.6%), eye pain (1 patient, 1.8%), congestion (1 patient, 1.8%), watering eyes (1 patient, 1.8%), and blurred vision (1 patient, 1.8%). These symptoms appeared during the early period of treatment, such as after the first or the second dose. We found that all patients had mild symptoms (Grade 1 or 2), and most improved spontaneously. Thus, eye disorders due to oxaliplatin affect Japanese patients somewhat frequently, although the symptoms are reversible and are mild in most cases. Detailed studies that include data from a larger number of facilities should be conducted in the future.

Hyponatremia is one of the electrolyte abnormalities frequently encountered in cancer therapy. Cisplatin is a well-known drug which can raise various adverse events, including hyponatremia. A male with advanced oropharyngeal cancer is presented in the present report, who was treated with radiotherapy with concurrent administration of cisplatin and who underwent a total of three episodes of severe hyponatremia in the course of therapy. The first two attacks of hyponatremia following cisplatin administration were accompanied by dehydration and excessive urination, and the patient recovered in one week with rehydration and salt supplementation. Excessive loss of salt in urine confirmed that these events were caused by renal salt wasting syndrome after cisplatin administration. On the other hand, the third attack was due to the syndrome of inappropriate antidiuretic hormone secretion after surgery for a bone fracture. Estimation of the extracellular fluid volume and salt intake/output balance is always believed to be necessary for the diagnosis and proper management of severe hyponatremia after chemotherapy-based treatment with cisplatin.

Drug delivery techniques to tumor cells have attracted considerable attention. For instance, folic acid (FA) as a tumor-targeting ligand is widely used because of overexpression of folate receptor-α (FR-α) in various kinds of epithelial tumor cells. On the other hand, methyl-β-cyclodextrin (M-β-CyD) is acknowledged to induce cell death through the extraction of cholesterol from lipid rafts. It was recently reported that intraperitoneal administration of M-β-CyD exerted antitumor activity in human tumor xenografted athymic nude mice. However, the cytotoxic activity of M-β-CyD is known to lack tumor cell selectivity. Therefore in the present study, in an attempt to confer tumor cell selectivity to M-β-CyD, we newly synthesized folate-appended M-β-CyD (FA-M-β-CyD) and evaluated its potential as a novel antitumor agent. FA-M-β-CyD showed potent antitumor activity in various FR-α-positive cells such as KB cells, Ihara cells, and M213 cells but not in FR-α-negative cells, A549 cells. FA-M-β-CyD induced the formation of autophagic vacuoles in KB cells. In addition, the antitumor activity of FA-M-β-CyD, but not M-β-CyD, was inhibited by addition of the autophagy inhibitors chloroquine and bafilomycin A1 in KB cells. A single intravenous injection of FA-M-β-CyD drastically inhibited tumor growth and significantly improved survival rate in Colon-26 cells-allografted or M213 cells-xenografted mice. In conclusion, FA-M-β-CyD has potential as a novel tumor-selective anticancer agent due to FR-α-mediated cellular uptake. The present results provide useful information for the design and development of novel antitumor drug carriers and antitumor drugs based on CyDs.

The recently discovered high mannose (HM)-binding lectin family in lower organisms such as bacteria, cyanobacteria, and marine algae represents a novel class of anti-viral or anti-tumor compounds. This lectin family shows unique carbohydrate binding properties with exclusive high specificity for HM glycans with core trisaccharide comprising Manα(1-3)Manα(1-6)Man at the D2 arm. At low nanomolar levels, these lectins exhibit potent antiviral activity against HIV and influenza viruses through the recognition of HM glycans on virus spike glycoproteins. In addition, some of these lectins, such as bacterial PFL, show cytotoxicity for various cancer cells at low micromolar levels. Cell surface molecules to which PFL bound were identified as integrin alpha 2 and epidermal growth factor receptor (EGFR) by peptide mass finger printing with MALDI-TOF MS. Upon PFL binding, these molecules were rapidly internalized to cytoplasm. EGFR was time dependently degraded in the presence of PFL, and this process was largely responsible for autophagy. Furthermore, PFL sensitizes cancer cells to the EGFR kinase inhibitor, gefitinib. In vivo experiments showed that intratumoral injection of PFL significantly inhibited the growth of tumors in nude mice. PFL-mediated down regulation of integrin/EGFR ultimately contributed to the inhibition of tumor growth both in vitro and in vivo. Thus, the novel anti-cancer mechanism of PFL suggests that this lectin is potentially useful as an anti-cancer drug or as an adjuvant for other drugs. This class of proteins will likely have beneficial impact as a tool for biochemical and biomedical research because of its unique carbohydrate specificity and various biological activities.

Sorafenib is a tyrosine kinase inhibitor (TKI) of the vascular endothelial growth factor receptor (VEGFR) used for advanced renal cell carcinoma. Treatment with sorafenib prolongs progression-free survival in patients with advanced clear-cell renal cell carcinoma. However, in spite of its therapeutic efficacy, sorafenib causes a wide range of adverse events. Cardiovascular adverse events have been observed when sorafenib was used with targeted agents. Although these adverse events like hypertension, reduced left ventricular ejection fraction, cardiac ischemia or infarction were manageable with standard medical therapies in most cases, some had a poor clinical outcome. We report three cases of acute myocardial infarction associated with sorafenib in patients with metastatic renal cell carcinoma.

Advances in molecular and cellular biochemistry, such as the development of targeted cancer therapy, have dramatically improved the prognosis of cancer patients. Emerging data have suggested that bevacizumab treatment may act by controlling the cancer microenvironment. Many reports have examined the interaction of cancer cells with the tumor microenvironment, and cancer-associated fibroblasts (CAFs) are thought to play a central role in this process. We speculated that the cancer microenvironment and in particular, CAFs, strongly influence the development of esophageal cancer. We have analyzed the signaling pathways of molecular targets. However, inhibition of a single signaling pathway is insufficient to treat cancer effectively. Photoimmunotherapy is a molecular-targeted specific cancer therapy using near-infrared radiation, which was introduced by Mitsunaga et al. in 2011. We are using its specific method of killing cells to target CAFs. We will report the results of its effect on cancer cells in the future.

In this study, we report the rare case of an elderly woman who developed thrombophlebitis after being treated with tamoxifen for breast cancer. She visited our department with a lump in her left breast. She underwent core needle biopsy, and she was diagnosed with breast cancer (invasive ductal carcinoma, ER- and PgR-positive, HER2-negative). We chose hormonal therapy because surgical treatment was deemed too invasive considering her general status. She was administered tamoxifen (20 mg/day) instead of an aromatase inhibitor in consideration of her osteoporosis. Six months after initiating tamoxifen therapy, she exhibited swelling in her left leg. Computed tomography and ultrasound revealed thrombophlebitis in her left femoral vein. She stopped taking tamoxifen and started warfarin potassium as thrombolytic therapy, after which thrombophlebitis was relieved. Advanced age may be a risk factor for thrombophlebitis associated with tamoxifen treatment; therefore, precautions should be taken accordingly.

Studies of neurological dysfunction have revealed the neuroprotective effect of several cationic drugs, suggesting their usefulness in the treatment of neurological diseases. In the brain and retina, blood-tissue barriers such as blood-brain barrier (BBB) and blood-retinal barrier (BRB) are formed to restrict nonspecific solute transport between the circulating blood and neural tissues. Therefore study of cationic drug transport at these barriers is essential to achieve systemic delivery of neuroprotective agents into the neural tissues. In the retina, severe diseases such as diabetic retinopathy and macular degeneration can cause neurological dysfunction that dramatically affects patients' QOL. The BRB is formed by retinal capillary endothelial cells (inner BRB) and retinal pigment epithelial cells (outer BRB). Blood-to-retina transport of cationic drugs was investigated at the inner BRB, which is known to nourish two thirds of the retina. Blood-to-retinal transport of verapamil suggested that the barrier function of the BRB differs from that of the BBB. Moreover, carrier-mediated transport of verapamil and pyrilamine revealed the involvement of novel organic cation transporters at the inner BRB. The identified transport systems for cationic drugs are sensitive to several cationic neuroprotective and anti-angiogenic agents such as clonidine and propranolol, and the involvement of novel transporters was also suggested in their blood-to-retina transport across the inner BRB.

With improvement of survival owing to the recent implementation of new anti-myeloma (MM) agents, bone management will become more important for maintaining the quality of life (QoL) of patients. Bisphosphonates are currently the standard of care for MM-related bone disease. Zoledronic acid is recommended for newly diagnosed MM patients receiving front-line anti-MM treatment regardless of existing detectable bone lesions. Intriguingly, an overall survival benefit has been observed with zoledronic acid in patients on anti-MM treatment with documented bone disease at baseline. Denosumab, a human monoclonal antibody against RANKL, has been demonstrated to reduce bone-related events in patients with MM as effectively as zoledronic acid. Hypocalcemia is generally accepted as occurring more frequently and more severely with denosumab than with zoledronic acid, especially in patients with renal insufficiency. Bisphosphonates but not denosumab deposit in bone with a long half-life, which may make a difference in long-term efficacy as well as adverse effects. Clinical benefits of long-term anti-resorptive therapies after achieving a good response should be clarified, in order to avoid the emergence of severe complications. Impacts of new agents in combination with these anti-resorptive agents on bone metabolism have yet to be studied.

We report a suspected photosensitive reaction induced by weekly paclitaxel (PTX) in a patient with breast cancer. The patient was a 72-year-old woman with right breast cancer (T2N1M0, Stage II B). She received 80 mg/m² PTX weekly as neoadjuvant chemotherapy. After the 5 courses of weekly PTX, she began to develop skin lesions with itchy sensations on the areas of her body that had been exposed to sunlight. The symptoms persisted after the 6 courses of weekly PTX, and topical steroid and antihistamine treatments were initiated. The skin lesions resolved once the patient avoided sunlight and used sunscreen. Ultimately, she received 12 courses of PTX. We need to recognize the appearance of a photosensitive reaction following weekly PTX for breast cancer.

Weight loss during chemotherapy is a result of malnutrition and metabolism abnormality. A few reports have focused on the treatment and prevention of weight and appetite loss in patients with advanced cancer. We evaluated the relationship between weight and appetite loss during chemotherapy by studying the meal intake of patients. In addition, we also investigated whether anorexia is associated with the level of 8-hydroxy-2' -deoxyguanosine (8-OHdG), an oxidation stress marker. The weight loss rate in patients who lack energy intake was significantly higher than that in patients with adequate energy intake. Moreover, the pre-chemotherapy total energy intake, measured according to the hospital meal consumption of patients, was lower among those with than among those without anorexia. The 8-OHdG levels in the patients with anorexia were significantly higher. In conclusion, nutritional management is important for patients even before chemotherapy is started. The 8-OHdG level can be used as an index to evaluate appetite.

To examine the effect of S-1 adjuvant chemotherapy on muscle volume after curative gastrectomy in gastric cancer patients.

Efficacy of cancer pharmacotherapy depends upon drug exposure to the body and responsiveness of the tumor to the drug treatment. Drug exposure is determined by pharmacokinetics and dose, whereas responsiveness is intrinsically variable by tumor heterogeneity. Molecular targeting drugs are used as promising therapy for cancers, and most of them are coupled with particular diagnostics which can predict responders and non-responders before treatment. On the other hand, lower drug exposure to the body can lead to insufficient efficacy. A number of important evidences have been published recently on exposure-response relationships for molecular targeting drugs including monoclonal antibodies and small molecules. In this chapter, two examples are presented; anti-HER2 antibody and tyrosine kinase inhibitor. Patients with the lowest trough concentrations of trastuzumab in cycle 1 showed shorter overall survival in metastatic gastric cancer study. Efficacy of imatinib in chronic myelogenous leukemia depended on plasma concentration of imatinib, and therapeutic drug monitoring (TDM) of imatinib is expected to improve the therapeutic outcome in CML.

Tumor angiogenesis contributes to the development of tumor progression. Several vascular endothelial growth factor(VEGF)-targeted agents, administered either as single agents or in combination with chemotherapy, have been shown to benefit patients with advanced-stage malignancies. In particular, bevacizumab is a humanized monoclonal antibody that specifically targets VEGF, inhibiting angiogenesis, thereby impeding tumor growth and survival. It is also possible that combined VEGF and the epidermal growth factor (EGFR) pathway blockade could further enhance antitumor efficacy and help prevent resistance to therapy. Preclinical and clinical studies have shown new various molecular targets and the functional characteristics of tumor angiogenesis, which may provide strategies for improving the therapeutic benefit.

Poly(ADP-ribose) polymerases(PARP) synthesize the ADP-ribose polymers onto proteins and play a role in DNA repair. PARP inhibitors block the repair of single-strand breaks, which in turn gives rise to double-strand breaks during DNA replication. Thus, PARP inhibitors elicit synthetic lethality in cancer with BRCA1/2 loss-of-function mutations that hamper homologous recombination repair of double-strand breaks. Olaparib, the first-in-class PARP inhibitor, was approved for treatment of BRCA-mutated ovarian cancer in Europe and the United States in 2014. Other PARP inhibitors under clinical trials include rucaparib, niraparib, veliparib, and the "PARP-trapping" BMN-673. BRCA1/2 sequencing is an FDA-approved companion diagnostics, which predicts the cancer vulnerability to PARP inhibition. Together, synthetic lethal PARP inhibition is a novel promising strategy for cancer intervention even in cases without prominent driver oncogenes.

Apoptosis and autophagy usually function to eliminate damaged cells and damaged proteins, respectively. Dysfunction of these events induces oncogenesis and cancer development. Therefore, small compounds that activate apoptosis and autophagy are good candidates for anti-cancer chemotherapeutics to combat cancers. This review focuses on recent advances in apoptosis/autophagy and their relationship with tumorigenesis.

Target-based screening and cell-based screening are major approaches to identify anticancer drug candidates. Cell-based screening often contributes to the discovery of first-in-class drugs, but identification of the cellular targets of obtained compounds is a time-consuming step. To overcome this problem, affinity purification with small-molecule probes, which is a classic, but still the most common approach, has become more sophisticated and diversified. In addition, recent advances in omics studies and imaging analyses have allowed us to profile the biological effects of small molecules globally and quantitatively. Consequently, new therapeutic targets/drug leads involved in cancer cell cycle, transcription and redox regulation have been discovered.

A 67-year-old woman was diagnosed with chronic lymphocytic leukemia (CLL) in October 2001. In August 2004, she received chemotherapy consisting of fludarabine and cyclophosphamide (FC therapy). After three cycles of FC therapy, the number of tumor cells was markedly decreased. However, anemia progressed. She was diagnosed with pure red cell aplasia (PRCA) by bone marrow examination and was successfully treated with cyclosporin A (CsA). In October 2008, anemia progressed with the exacerbation of CLL and she received three cycles of fludarabine therapy. Although the number of tumor cells diminished, the anemia did not improve. She was diagnosed with PRCA recurrence and was again successfully treated with CsA. PRCA is a rare complication in patients with CLL and has been attributed to T cell-mediated mechanisms. Six cases with PRCA that developed after fludarabine therapy for CLL have already been reported. Fludarabine therapy may be toxic to Treg, resulting in the loss of self-tolerance. It is important to consider the possibility of PRCA in patients with progressive anemia after fludarabine therapy for CLL.